(19)
(11)EP 3 360 967 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
09.09.2020 Bulletin 2020/37

(21)Application number: 18163611.9

(22)Date of filing:  01.06.2012
(51)International Patent Classification (IPC): 
C12N 15/63(2006.01)
C12R 1/46(2006.01)
C12N 15/90(2006.01)

(54)

POLYCISTRONIC EXPRESSION SYSTEM FOR BACTERIA

POLYCISTRONISCHES EXPRESSIONSSYSTEM FÜR BAKTERIEN

SYSTÈME D'EXPRESSION POLYCISTRONIQUE POUR DES BACTÉRIES


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 01.06.2011 EP 11168495
12.07.2011 EP 11173588

(43)Date of publication of application:
15.08.2018 Bulletin 2018/33

(62)Application number of the earlier application in accordance with Art. 76 EPC:
12729396.7 / 2714912

(73)Proprietor: Intrexon Actobiotics NV
9052 Zwijnaarde (BE)

(72)Inventors:
  • Vandenbroucke, Klaas
    9840 De Pinte (BE)
  • van Huynegem, Karolien
    9890 Asper (BE)
  • Steidler, Lothar
    9160 Lokeren (BE)

(74)Representative: Pohlman, Sandra M. 
df-mp Dörries Frank-Molnia & Pohlman Patentanwälte Rechtsanwälte PartG mbB Theatinerstrasse 16
80333 München
80333 München (DE)


(56)References cited: : 
WO-A2-01/62944
  
  • BRÜCKNER R: "Gene replacement in Staphylococcus carnosus and Staphylococcus xylosus.", FEMS MICROBIOLOGY LETTERS 1 JUN 1997 LNKD- PUBMED:9198277, vol. 151, no. 1, 1 June 1997 (1997-06-01), pages 1-8, XP002659297, ISSN: 0378-1097
  • DOBINSKY SABINE ET AL: "Influence of Tn917 insertion on transcription of the icaADBC operon in six biofilm-negative transposon mutants of Staphylococcus epidermidis", PLASMID, vol. 47, no. 1, January 2002 (2002-01), pages 10-17, XP002659298, ISSN: 0147-619X
  • ROSEY E L ET AL: "NUCLEOTIDE AND DEDUCED AMINO ACID SEQUENCES OF THE LACR, LACABCD, AND LACFE GENES ENCODING THE REPRESSOR, TAGATOSE 6-PHOSPHATE GENE CLUSTER, GENE CLUSTER, AND SUGAR-SPECIFIC PHOSPHOTRANSFERASE SYSTEM COMPONENTS OF THE LACTOSE OPERON OF STREPTOCOCCUS MUTANS", JOURNAL OF BACTERIOLOGY, AMERICAN SOCIETY FOR MICROBIOLOGY, WASHINGTON, DC; US, vol. 174, no. 19, 1 October 1992 (1992-10-01), pages 6159-6170, XP000856001, ISSN: 0021-9193
  • LOTHAR STEIDLER ET AL: "Genetically modified Lactococcus lactis: novel tools for drug delivery", INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, vol. 59, no. 2, 1 May 2006 (2006-05-01), pages 140-146, XP055472305, GB ISSN: 1364-727X, DOI: 10.1111/j.1471-0307.2006.00255.x
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

FIELD OF THE INVENTION



[0001] The invention belongs to the fields of biology and medicine, more particular molecular and cellular biology, and relates to recombinant engineering and expression of products such as peptides, polypeptides or proteins by gram-positive bacteria. More specifically, the invention relates to a gram-positive bacterium and a recombinant nucleic acid comprising a polycistronic expression unit for expression of such products, and further to related vectors, transformed hosts, uses and applications, such as delivery, especially therapeutic delivery, of so-expressed products to subjects.

BACKGROUND OF THE INVENTION



[0002] To date, many expression systems for recombinant proteins have been developed, for various biotechnological applications. Systems for heterologous or homologous gene expression have been established in prokaryotes, yeasts and fungi and in mammalian cells.

[0003] Most recombinant proteins produced in yeasts have been expressed using Saccharomyces cerevisiae as the host system. Despite this, several limitations have been detected in the S. cerevisiae system. Examples are product yield, which is usually low, and inefficient secretion (many S. cerevisiae proteins are not found free in the culture medium but rather are retained in the periplasmic space or associated with the cell wall) (Dominguez et al. Int. Microbiol., 1998, vol. 1(2), 131-142). Because of limitations of production in yeast, a lot of interest arose for expression of proteins in bacteria, which are easy to grow in an inexpensive broth and are frequently used to produce recombinant proteins. Among prokaryotic systems, the highest protein levels are usually obtained using recombinant expression in Escherichia coli (E. coli) (Jana & Deb. Appl. Microbiol. Biotechnol., 2005, vol. 67(3), 289-298). However, in E. coli, the most commonly used production strategies are intracellular (in the periplasm or cytoplasm), and therefore involve expensive and often problematic downstream purification processes.

[0004] Lactic Acid Bacteria (LAB) are becoming increasingly important as hosts for recombinant expression of heterologous polypeptides in vitro (e.g., US 5,559,007), as well as for in vivo or in situ expression and delivery of antigens and/or therapeutically relevant polypeptides (e.g., WO 97/14806). Heterologous proteins produced in these Gram-positive bacterial hosts can easily be secreted into the medium, thus facilitating their purification as well as their direct delivery to subjects.

[0005] Most expression systems can handle very well the expression of one single protein (as a result of one single gene sequence). However, in some cases it is desirable to have an expression system that is capable of expressing multiple proteins or multigenic protein complexes, for example, the in vitro expression of antibodies or protein complexes, but also in vivo or in situ expression and delivery of two or more proteins that have a synergistic effect in a particular disease or the in vivo or in situ expression and delivery of antibodies or functional (multigenic) fragments thereof. In these cases, it is desirable to have the multiple genes that are encoding the desired proteins or antibodies under the control of one promoter, because of the necessity of tight co-regulation of the multiple genes.

[0006] The two most common approaches to produce recombinant protein complexes are to perform in vitro reconstitution of individually expressed and purified subunits, or to implement in vivo reconstitution by co-expressing the subunits in an appropriate host (Selleck & Tan, "Recombinant protein complex expression in E. coli", Curr. Protoc. Protein Sci., 2008, chapter 5:unit 5, 21). Although in vitro reconstitution has been successfully used, the process is tedious (each subunit has to be expressed and purified, and the complex has to be further purified after reconstitution) and reconstitution yields are often low. In contrast, in vivo reconstitution by co-expression offers the benefits of efficiency (only one round of expression and purification) and potentially higher yields and quality of the desired complex (refolding and assembly of the complex take place in the presence of protein folding enzymes in a cellular environment) (Selleck & Tan 2008, supra). In vivo reconstitution has been successfully performed by co-infecting insect cells with baculoviruses expressing individual protein subunits (Tirode et al. Mol. Cell, 1999, vol. 3(1), 87-95), and in bacteria from multiple plasmids (Johnston et al. Protein Expr. Purif., 2000, vol. 20(3), 435-443; McNally et al. Proc. Natl. Acad. Sci. USA, 1988, vol. 85(19), 7270-7273) or from specialized polycistronic plasmids (Henricksen et al. J. Biol. Chem., 1994, vol. 269(15), 11121-11132; Ishiai et al. J. Biol. Chem. 1996, vol. 271(34), 20868-20878; Li et al. Proc. Natl. Acad. Sci. USA, 1997, vol. 94(6), 2278-2283).

[0007] General polycistronic expression systems for producing protein complexes in E. coli have been described (Selleck & Tan 2008, supra; Tan. Protein. Expr. Purif., 2001, vol. 21(1), 224-234; Tan et al. Protein Expr. Purif., 2005, vol. 40(2), 385-395). These systems utilize the concept of a translation cassette, comprised of the coding region with requisite START and STOP codons and preceded by translational initiation signals such as the Shine-Dalgarno (SD) sequence and translational enhancers (Tan 2001, Tan et al. 2005, supra). When transcribed into mRNA, the translation cassette contains the necessary and sufficient information for the E. coli translational machinery to initiate and sustain translation of the mRNA into the desired polypeptide (Selleck & Tan 2008, supra).

[0008] A bi-cistronic expression vector for interleukin-18 has been described in E. coli, however, the intergenic region between the two genes consisted of a synthetic linker, and is clearly gene-specific as the expression of the caspase-4 was much higher than the expression of ICE. Smolke et al. previously demonstrated that it is possible to differentially control the protein levels encoded by two or more genes in an operon using synthetic intergenic region sequences (Smolke et al. Appl. Environ. Microbiol., 2000, vol. 66(12), 5399-5405; Smolke & Keasling. Biotechnol. Bioeng., 2002, vol. 80(7), 762-776). However, this approach relies on random combinations, and requires the introduction of synthetic sequences into the expression host.

[0009] The demand for new and improved antibody production systems has arisen in recent years. Systems for antibody expression have been established in prokaryotes, yeasts and fungi and in mammalian cells. Although single chain and single domain antibodies are easier to produce from bacteria, full-size antibodies generally have higher binding affinities and less risk for formation of neutralizing antibody when injected.

[0010] Full-size antibodies can be produced from bacteria (Mazor et al. Nat. Biotechnol., 2007, vol. 25(5), 563-565; Simmons et al. J. Immunol. Methods, 2002, vol. 263(1-2), 133-147). Most reports on recombinant prokaryotic expression describe production of antibody fragments, albeit almost exclusively from E. coli. Although many engineered LAB are capable of correct disulphide bonding, the literature contains only a limited number of examples of antibody-like molecules produced from LAB (Kruger et al. Nature Biotechnology, 2002, vol. 20(7), 702-706; Beninati et al. Nature Biotechnology, 2000, vol. 18(10), 1060-1064; Chancey et al. J. Immunol., 2006, vol. 176(9), 5627-5636; Hultberg et al. BMC Biotechnol., 2007, vol. 7, 58; Yuvaraj et al. Mol. Nutr. Food. Res., 2008, vol. 52(8), 913-920). These reports only describe single chain antibody fragments expressed in Lactobacillus species, Lactococcus lactis and Streptococcus gordonii, and not multigenic, double chain antibody fragments or full-sized antibodies.

[0011] Polycistronic expression systems could be crucial in obtaining efficient prokaryotic synthesis and expression of complex proteins such as antibodies. Since the FDA approval in 1986 of Muromonab-CD3, still one of the most potent immunosuppressive drugs available for the management of transplant rejection (Hooks et al. Pharmacotherapy, 1991, vol. 11(1), 26-37), full-size antibodies and antibody fragments have become increasingly important and versatile tools in medicine.

[0012] While the current state of the art reveals several examples of polycistronic expression systems in bacterial cells, these are quite limited, highlighting the need for a more efficient system for introducing and expressing multiple genes. Accordingly, there exists a need to provide further sequences which can be favourably used for expression of proteins, preferably heterologous protein expression and even more preferably multiple heterologous protein expression.

[0013] In addition to the above, the endeavour to produce higher amounts of recombinant protein, both for direct protein delivery by recombinant microorganisms as well as for bulk protein production and down stream purification, represents a great technological strive. An existing approach to increase production of heterologous proteins is the use of selected strong promoters (see for instance WO 2008/084115). In this approach, proteomic analysis is performed to identify the most abundant endogenous proteins expressed by a microorganism. By use of the genome sequence, the respective genes and promoters can be identified and isolated. These strong promoters (e.g. the Lactococcus lactis hIIA gene promoter, PhIIA) can be positioned in front of a heterologous gene and in this way, high expression can be achieved. However, a level of expression which impairs host physiology may impose a growth burden on the host and results in counter-selection. This intrinsically limits the highest possible expression of any given heterologous protein in an expression host to a certain specific level. This is an especially cumbersome obstacle in the development of chromosomally located expression units.

[0014] The issue of counter-selection is traditionally addressed by the provision of selection markers. Indeed, positive or negative selection, e.g. by providing antibiotic resistance genes, can prevent loss of the introduced heterologous gene. Alternatively, or in addition to the use of selection markers, inducible gene expression systems may be employed, which allow for uncoupling propagation of the host and expression of the heterologous protein, thereby preventing possible counter-selection during the propagation phase when the heterologous gene is not expressed. In this context, EP0569604 describes an inducible expression system in Streptococcus thermophilus in which a heterologous gene is obligatory positioned 5' to the LacZ gene. In this way, expression of the heterologous gene is not only inducible but in addition maintenance of the heterologous gene is also selected for by growing the bacteria in their natural habitat, milk, with lactose as carbon source, which requires the expression of the LacZ gene.

[0015] WO 01/62944 describes two new chromosomal integration sites for expression of foreign genes in Streptococcus gordonii. One integration site is intergenic between orfA and orfB in an operon of unknown function. The other site is intragenic within the lacG gene, which encodes phospho-beta-galactosidase, and is part of the lactose (lac) operon.

[0016] Brückner R., 1997. FEMS Microbiology Letters. 151(1):1-8 describes gene replacement vectors for Staphylococci comprising the erythromycin resistance gene ermB.

[0017] Dobinsky S, et al., 2002. Plasmid. 47(1):10-27 shows various Tn917 insertions in the icaADBC operon of Staphylococcus epidermidis encoding the polysaccharide intercellular adhesin.

[0018] Rosey E.L and Stewart G.C, 1992. Journal of Bacteriology ASM.174(19):6159-6170 presents the complete nucleotide sequence of lacRABCDF and partial nucleotide sequence of lacE from the lactose operon of Streptococcus mutans.

[0019] Steidler L, et al., 2006. International Journal of Dairy Technologoy.59(2):140-146 discusses recombinant expression in Lacotoccus lactis.

[0020] It is clear that the systems for heterologous gene expression described above are limited in application. For instance, the use of selection markers, such as antibiotic resistance genes, is not readily tolerated for applications in food production or in pharmaceutical applications. Further, limitation to growing in the natural habitat or to using the carbon source from the natural habitat for growth significantly reduces the versatility of any system for heterologous gene expression. Also, the use of inducible systems is inherently dependent on the growth conditions of the host, such that defined culture media, to which an inducer is to be added, are needed to ensure expression of the heterologous protein.

[0021] Accordingly, there also exists a need in the art to increase heterologous protein expression; and sequences, cloning systems and strategies are needed which can achieve high expression levels in order to obtain sufficient amounts of expressed heterologous proteins in industrial and/or therapeutic settings, while at the same time being versatile and widely applicable under a variety of different conditions. In these settings it would also be particularly useful to obtain expression of multiple proteins, each having its own biological activity and therapeutic effect.

SUMMARY OF THE INVENTION



[0022] The aspects and embodiments of the present invention address at least some, e.g., one or more, of the above discussed needs of the art.

[0023] The inventors have surprisingly found that gram-positive bacteria can efficiently express exogenous or heterologous genes from polycistronic expression units also comprising endogenous gene(s) of these bacteria. Thus, gram-positive bacteria can efficiently express exogenous or heterologous genes from polycistronic expression units when such genes are transcriptionally or translationally coupled to endogenous gene(s) of these bacteria. Unexpectedly, the inventors have found that transcriptional and/or translational coupling of endogenous genes and exogenous genes in polycistronic expression units results in high expression levels of the exogenous genes in gram-positive bacteria. In particular, expression levels of exogenous genes transcriptionally and/or translationally coupled to gram-positive bacterial endogenous genes were found to be at least comparable to and advantageously higher than expression levels of exogenous genes which are not transcriptionally or translationally coupled to gram-positive bacterial endogenous genes.

[0024] The invention provides a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising an endogenous gene and one or more exogenous genes, wherein said endogenous gene and said one or more exogenous genes are transcriptionally controlled by a promoter endogenous to the gram-positive bacterium, wherein said promoter is
  1. (i) a ribosomal gene promoter selected from the group consisting of:

    (a) an rpmD promoter,

    (b) an rpsD promoter,

    (c) an rpsL promoter,

    (d) an rpsG promoter,

    (e) an rplR promoter,

    (f) an rpsE promoter,

    (g) an rpsK promoter,

    (h) an rplJ promoter,

    (i) an rplL promoter,

    (j) an rpsB promoter,

    (k) an rplD promoter,

    (I) an rplW promoter,

    (m) an rplB promoter,

    (n) an rplO promoter,

    (o) an rplK promoter,

    (p) an rpsH promoter,

    (q) an rpsM promoter,

    (r) an rpsS promoter,

    (s) an rplU promoter,

    (t) an rplV promoter,

    (u) an rplP promoter

    (v) an rplN promoter,

    (w) an rpsJ promoter,

    (x) an rplX promoter,

    (y) an rplE promoter,

    (z) an rplF promoter, and

    (aa) an rplM promoter;

  2. (ii) a glycolysis gene promoter promoter selected from the group consisting of:
    1. (a) an fbaA promoter, and
    2. (b) a pgk promoter; or
  3. (iii) a dpsA promoter
of said gram-positive bacterium.

[0025] The invention also provides a recombinant nucleic acid comprising a polycistronic expression unit, said polycistronic expression unit comprising a gene endogenous to a gram-positive bacterium and one or more genes exogenous to the gram-positive bacterium, wherein said endogenous gene and said one or more exogenous genes are transcriptionally controlled by a promoter endogenous to the gram-positive bacterium, wherein said promoter is
  1. (i) a ribosomal gene promoter selected from the group consisting of:

    (a) an rpmD promoter,

    (b) an rpsD promoter,

    (c) an rpsL promoter,

    (d) an rpsG promoter,

    (e) an rpIR promoter,

    (f) an rpsE promoter,

    (g) an rpsK promoter,

    (h) an rplJ promoter,

    (i) an rplL promoter,

    (j) an rpsB promoter,

    (k) an rplD promoter,

    (I) an rplW promoter,

    (m) an rplB promoter,

    (n) an rplO promoter,

    (o) an rplK promoter,

    (p) an rpsH promoter,

    (q) an rpsM promoter,

    (r) an rpsS promoter,

    (s) an rplU promoter,

    (t) an rplV promoter,

    (u) an rplP promoter

    (v) an rplN promoter,

    (w) an rpsJ promoter,

    (x) an rplX promoter,

    (y) an rplE promoter,

    (z) an rplF promoter, and

    (aa) an rplM promoter;

  2. (ii) a glycolysis gene promoter promoter selected from the group consisting of:
    1. (a) an fbaA promoter, and
    2. (b) a pgk promoter; or
  3. (iii) a dpsA promoter
of said gram-positive bacterium.

[0026] The invention also provides a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising, in 5' to 3' order:
  1. (i) the gapB promoter endogenous to said gram positive bacterium;
  2. (ii) the gapB gene endogenous to said gram positive bacterium; and
  3. (iii) the exogenous gene human trefoil factor coupled to the Lactococcus Usp45 secretion signal (SS:TFF1),
wherein the gapB gene is transcriptionally coupled to SS:TFF1 via the intergenic region preceding rpmD in the said gram positive bacterium, wherein the intergenic region preceding rpmD comprises the sequence of SEQ ID NO: 3 or SEQ ID NO: 9.

[0027] The invention also provides a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising, in 5' to 3' order:
  1. (i) the usp45 promoter endogenous to said gram positive bacterium;
  2. (ii) the usp45 gene endogenous to said gram positive bacterium; and
  3. (iii) the exogenous gene human trefoil factor coupled to the Lactococcus Usp45 secretion signal (SS:ins),
wherein the usp45 gene is transcriptionally coupled to SS:ins via the intergenic region preceding rpmD in the said gram positive bacterium, wherein the intergenic region preceding rpmD comprises the sequence of SEQ ID NO: 3 or SEQ ID NO: 9.

[0028] The invention also provides a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising, in 5' to 3' order:
  1. (i) the enoA promoter endogenous to said gram positive bacterium;
  2. (ii) the enoA gene endogenous to said gram positive bacterium; and
  3. (iii) the exogenous gene human trefoil factor coupled to the Lactococcus Usp45 secretion signal (SS:ins),
wherein the usp45 gene is transcriptionally coupled to SS:ins via the intergenic region preceding rpmD in the said gram positive bacterium, wherein the intergenic region preceding rpmD comprises the sequence of SEQ ID NO: 3 or SEQ ID NO: 9.

[0029] Accordingly, in an aspect the invention relates to a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising an endogenous gene (for example but without limitation one endogenous gene) and one or more exogenous genes. Preferably, the polycistronic expression unit consecutively comprises an endogenous gene and one or more exogenous genes. Such polycistronic expression unit can thus also be denoted as consecutively comprising an endogenous gene (for example but without limitation one endogenous gene) and one or more exogenous genes. The polycistronic expression unit is configured to effect transcription of an endogenous gene and the one or more exogenous genes in a polycistronic mRNA. Hence, the present gram-positive bacterium may otherwise be denoted as comprising an endogenous gene to which one or more exogenous genes are transcriptionally or translationally coupled. Also provided is a gram-positive bacterium comprising an endogenous gene to which one or more exogenous genes are transcriptionally and/or translationally coupled.

[0030] Another aspect relates to a recombinant nucleic acid comprising a polycistronic expression unit, said polycistronic expression unit comprising a gene endogenous to a gram-positive bacterium and one or more genes exogenous to the gram-positive bacterium. Preferably, the polycistronic expression unit consecutively comprises an endogenous genes and one or more exogenous genes. Also provided is a recombinant nucleic acid comprising a polycistronic expression unit comprising a gene endogenous to the gram-positive bacterium to which one or more genes exogenous to the gram-positive bacterium are transcriptionally and/or translationally coupled.

[0031] Preferably, as intended throughout this specification said one or more exogenous genes may be transcriptionally or translationally coupled to the 3' end of said endogenous gene. The inventors have surprisingly found that such configuration is beneficial in respect of heterologous protein expression levels, maintenance and/or genomic stability of the polycistronic expression unit. It has moreover been found that further downstream genomic arrangement is of lesser or no importance. The transcription of the transcriptionally or translationally coupled endogenous gene and one or more exogenous genes may be suitably regulated or controlled by a promoter capable of achieving transcription in the gram-positive bacterium, and is regulated or controlled by an endogenous promoter of said gram-positive bacterium. Hence, also provided is a gram-positive bacterium comprising an endogenous gene located in its native chromosomal locus, to which one or more exogenous genes are transcriptionally or translationally coupled. Preferably, transcription of these transcriptionally or translationally coupled endogenous gene and one or more exogenous genes is controlled or regulated by the native promoter of said endogenous gene. Suitably, the transcriptional or translational coupling may be achieved by chromosomally integrating the one or more exogenous genes to said locus, preferably by chromosomally integrating the one or more exogenous genes 3' of said endogenous gene in said locus.

[0032] Accordingly, in an aspect, the invention relates to a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, preferably wherein said one or more exogenous gene(s) is (are) the most 3' gene(s) of the polycistronic expression unit.

[0033] The inventors have surprisingly found that chromosomal integration of an exogenous or heterologous gene (or multiple heterologous genes) transcriptionally coupled 3' to a native gene, which in itself may be a polycistronic gene, such as for instance an operon, yields a stable expression unit, in which counter selection against the (one or more) exogenous gene is absent or minimal, contrary to expectations.

[0034] The inventors have unexpectedly found that the herein described advantages are increasingly manifested when the expression of the polycistronic expression unit is effected under certain conditions, in particular by certain types of promoters. The inventors have surprisingly found that polycistronic expression systems as described herein, in which counter-selection against the heterologous protein(s) is not addressed by conventional measures, such as the use of selection markers, or by the use of inducible systems, may nevertheless be stably maintained and expressed at high levels, thereby being broadly applicable under a variety of different conditions, absent the need of selection agents or inducers. The polycistronic expression modules as described herein thus allow the use of non-selectable endogenous and/or exogenous genes.

[0035] Described herein is a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is effected by a constitutive promoter.

[0036] Described herein is a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is effected by a central metabolism gene promoter.

[0037] Described herein is a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is effected by a housekeeping gene promoter.

[0038] Described herein is a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is effected by an essential gene promoter.

[0039] Described herein is a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is not effected by an inducible gene promoter.

[0040] In another aspect, the invention relates to a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is effected by a ribosomal gene promoter.

[0041] In another aspect, the invention relates to a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is effected by a glycolysis gene promoter.

[0042] The promoters as described above are endogenous gene promoters. As is also detailed further below, the promoters as used herein are strong promoters. As described herein, the endogenous promoter may be selected from the group consisting of the promoters of eno, usp45, gapB, pyk, rpmB, and rplS. Transcription of the translationally coupled endogenous gene and one or more exogenous gene may be regulated or controlled by the native promoter of said endogenous gene.

[0043] Described herein is a recombinant nucleic acid or a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit consecutively comprising an endogenous gene and one or more exogenous genes transcriptionally coupled to the 3' end of said endogenous gene, wherein expression of said polycistronic expression unit is effected by for instance a (endogenous) constitutive housekeeping gene promoter, a (endogenous) constitutive central metabolism gene promoter, a (endogenous) constitutive essential gene promoter, a (endogenous) constitutive ribosomal gene promoter, a (endogenous) constitutive glycolysis gene promoter, a (endogenous) central metabolism housekeeping gene promoter, a (endogenous) essential central metabolism gene promoter, a (endogenous) essential central metabolism housekeeping gene promoter, a (endogenous) essential housekeeping gene promoter, a (endogenous) constitutive central metabolism housekeeping gene promoter, a (endogenous) constitutive essential central metabolism housekeeping gene promoter, a (endogenous) essential ribosomal gene promoter, a (endogenous) essential glycolysis gene promoter, a (endogenous) constitutive essential ribosomal gene promoter, a (endogenous) constitutive essential glycolysis gene promoter.

[0044] Preferably as intended throughout this specification said one or more exogenous genes may be transcriptionally or translationally coupled to the 3' end of said endogenous gene whereby the endogenous gene is present at its native position on the bacterial chromosome. In this configuration, the sequence at the 5' end of the endogenous gene (minimally including the endogenous gene promoter) is identical to that of the wild type strain and the region subsequent to the 3' end of the one or more exogenous genes are identical to the sequence of the region 3' of the endogenous gene as in the wild type strain.

[0045] Many applications of exogenous protein expression such as for instance for therapeutic protein delivery by recombinant microorganisms can benefit from the expression of said therapeutic protein in specific selected host microorganisms. These microorganisms could be selected based on their colonizing capacity, as e.g. selected strains originating from the human or animal microbiota. Microorganisms could also be selected on their capacity to potentiate the activity of any specific delivered therapeutic protein e. g. as a consequence of the interaction of their cell wall, cell surface or intracellular content with the host immune system e.g. through interaction with toll like receptors, Ig family members, complement, cytokines and other. Specific microorganisms could be selected for their robustness to persist in or on specific harsh delivery sites, such as intratumoural, skin, sites with high bile content, sites with low pH and other. The gram-positive bacterium as recited throughout this specification may be preferably a lactic acid bacterium (LAB), more preferably a Lactococcus sp., even more preferably Lactococcus lactis or a subspecies or strain thereof. Alternatively, said LAB may be preferably an Enterococcus sp., more preferably Enterococcus fecium or Enterococcus faecalis or a subspecies or strain thereof.

[0046] To avoid lateral gene transfer to endogenous microflora, expression from a chromosomally embedded expression unit is highly favourable for use of recombinant microflora as delivery tools for therapeutic proteins in medicine. Also, chromosomally located expression units may prove to be much more stably inherited over generations, so that chromosomally located expression units may be the desirable structure for production strains used in bulk protein production. In the current state of the art, chromosomal insertion is performed by use of knock-in (KI) type vectors which are conditionally non-replicative and which contain the heterologous gene in-between flanking regions that allow homologous recombination. In a conventional approach (see for instance WO 2008/084115), the KI plasmid is constructed in the homologous host (KI plasmid for L. lactis is built in L. lactis). This is especially the case for heterologous expression that requires protein secretion, as many secretion signals are not compatible for use in other hosts. The use of strong promoters in expression constructs that are intended to be placed on the bacterial chromosome is hampered by expression of the heterologous gene from the KI plasmid intermediates. The heterologous gene is immediately preceded by a strong promoter, making that the expression from the KI plasmid, although not intended and not required, intrinsically limits the use of the strongest promoters. In many cases, the KI plasmid has a copy number that is a multiplicity of the chromosome number in the host, making that upon integration, expression will be several fold lower. Therefore, chromosomal expression units will be intrinsically weaker than what would be the highest achievable. This problem is circumvented by the invention described here. In this approach, the heterologous genes will be positioned downstream and transcriptionally and/or translationally coupled to a (strongly expressed) endogenous gene on the bacterial chromosome. This strategy does not require the endogenous (strong) promoter to be present on the KI plasmid. Rather, upstream of the heterologous gene, the promoterless 3' end of the (strongly expressed) endogenous gene is positioned. This type of KI plasmid is silent and will not limit the use of strong promoters.

[0047] The transcriptional or translational coupling of one or more exogenous genes with an endongenous gene as described herein may be achieved by means of an intergenic region active (i.e., functional, effective) in a gram-positive bacterium, preferably by means of an endogenous intergenic region of a gram-positive bacterium. Accordingly, described herein is a recombinant nucleic acid comprising an intergenic region active in a gram-positive bacterium, preferably an endogenous intergenic region of a gram-positive bacterium, operably linked to a gene exogenous to said gram-positive bacterium. The operable linkage ensures that a transcript of the intergenic region, present on a mRNA together with a transcript of the exogenous gene, is able to provide a site for initiation of translation of the exogenous gene, in the gram-positive bacterium. Preferably, the intergenic region may be provided 5' of the exogenous gene. The nucleic acid may comprise two or more exogenous genes in polycistronic arrangement, each exogenous gene preceded by an intergenic region. The intergenic regions may be the same or different. For example, where the intergenic regions are different, these may correspond to intergenic regions derived from different genes of the same or different species, or from the same gene of different species. These nucleic acids may be useful in constructing polycistronic expression units comprising the one or more exogenous genes, whereby one or more other gene is transcriptionally or translationally coupled with the one or more exogenous genes via the intergenic region. For example, these nucleic acids may be useful in constructing polycistronic expression units as taught herein, whereby an endogenous genes is transcriptionally or translationally coupled with the one or more exogenous genes via the intergenic region. Preferably the first cistron of the polycistronic expression unit will be a strongly expressed endogenous gene.

[0048] The present recombinant nucleic acids may be comprised on a replicon. An aspect thus also relates to a replicon or vector comprising the nucleic acid as taught herein. For example, the vector may be a prokaryotic expression vector, preferably a prokaryotic polycistronic expression vector. The development of such plasmid expression systems may however be tedious because the combination of certain replicons and strong promoters may be unstable. Also it may be impossible to transform selected microorganisms with recombinant plasmids and stably maintain the latter in the microorganism because of the presence of natural plasmids, especially not if no antibiotic selection markers may be included in the expression plasmid, as would be the case in an application for therapeutic protein delivery. This issue can be circumvented by positioning the heterologous genes downstream and transcriptionally or translationally coupled to a (strongly expressed) endogenous gene on the bacterial chromosome. As this strategy does not require a plasmid borne expression system, it can be used as a general approach to be applied for the genetic engineering of any type of selected microflora. The only strain specific information required can be rapidly established through state of the art technology. High throughput sequencing combined with proteomic analysis of the abundantly expressed proteins will rapidly yield the nucleotide sequence of the regions encoding the abundantly present proteins. Accordingly, most preferably, the vector as described herein may be configured to effect homologous recombination in the gram-positive bacterium, such as to generate a chromosomal integration of the exogenous gene(s).

[0049] Further provided is the use of the recombinant nucleic acid or vector as described herein for polycistronic expression of the one or more exogenous genes or for polycistronic expression of the endogenous gene and one or more exogenous genes in the gram-positive bacterium. As well disclosed is the gram-positive bacterium comprising (for example, transformed with) the recombinant nucleic acid or vector as taught herein, whereby the gram-positive bacterium is capable of polycistronic expression of the one or more exogenous genes or of polycistronic expression of the endogenous gene and one or more exogenous genes. Further provided is a method for effecting polycistronic expression of the one or more exogenous genes or for effecting polycistronic expression of the endogenous gene and one or more exogenous genes in a gram-positive bacterium, comprising the step of introducing the recombinant nucleic acid or vector as taught herein to said gram-positive bacterium. As well provided is a method for generating a gram-positive bacterium capable of polycistronic expression of the one or more exogenous genes or capable of polycistronic expression of the endogenous gene and one or more exogenous genes, comprising the step of introducing the recombinant nucleic acid or vector as taught herein to said gram-positive bacterium.

[0050] The invention allows to express, preferably strongly (highly) express, a single exogenous gene or a plurality of (e.g., two, three or more) distinct exogenous genes in a gram-positive bacterium. Said exogenous gene or genes may encode expression product or products such as advantageously protein(s), polypeptide(s) and/or peptide(s). By means of example and not limitation, such protein(s), polypeptide(s) and/or peptide(s) may encompass antigens (for example, for inducing immunity or immunotolerance), allergens, non-vaccinogenic therapeutic polypeptides (cytokines, growth factors, wound healing factors,...), antibodies or functional fragments thereof (e.g., Fab fragments), fusion proteins, multimeric proteins, etc and any combination thereof.

[0051] The polycistronic organisation may render expression units as taught herein particularly suitable for the expression of proteins comprising two or more polypeptide chains (e.g., multimeric proteins, protein complexes). Accordingly, two or more exogenous genes as intended in this specification may preferably encode distinct monomers or subunits of a multimeric protein, whereby the genes are co-transcribed into a polycistronic mRNA and the individual monomers or subunits are translated from this mRNA. This can allow for tightly regulated co-expression of the exogenous genes, such as to achieve balanced and optimal assembly of the individual monomers or subunits into the multimeric protein.

[0052] A particularly advantageous illustration of this principle is the expression of antibodies or functional fragments thereof. Hence, the two or more exogenous genes as taught herein may preferably encode separate chains of an antibody or of a functional fragment thereof. For example, one exogenous gene may encode the light chain (VL) of an antibody or of a functional fragment thereof, and another exogenous gene may encode the heavy chain (VH) of the antibody or of a functional fragment thereof. Preferably, the functional fragment of the antibody may be Fab. In specific but nonlimiting embodiments, said Fab may be binding to and/or inhibiting the biological effect of cytokines, receptors of cytokines, chemokines or immune/inflammatory activating molecules. In a preferred embodiment the Fab may be binding to and/or inhibiting the biological effect of TNFα, such as without limitation said Fab may be cA2 anti-TNF or CDP870 anti-TNF.

[0053] The exogenous genes encoding the individual chains of the antibody or of the fragment thereof are thus transcriptionally or translationally coupled for polycistronic expression in the gram-positive bacterium. Preferably, the exogenous gene encoding VL or functional fragment thereof may be transcriptionally or translationally coupled to the 3' end of the exogenous gene encoding VH or functional fragment thereof. This gene organisation yields particularly effective expression and assembly of the antibody or functional fragment thereof.

[0054] The polycistronic organisation may also render expression units as taught herein particularly suitable for the co-expression of products such as proteins that cooperate to achieve a synergistic effect, for example a synergistic therapeutic or prophylactic effect, for example when delivered in situ by the bacterium.

[0055] Another aspect provides a gram-positive bacterium as taught herein, wherein the one or more exogenous genes encodes a product or products such as protein(s), polypeptide(s) or peptide(s) having a therapeutic or preventive effect in a subject. Such bacterium is particularly provided for use as a medicament, more particularly for use in administration or delivery of said product or products to the subject, even more particularly for use in the treatment of a disease that can benefit from the administration or delivery of said product or products. Also provided is thus a pharmaceutical composition comprising such gram-positive bacterium.

[0056] As well provided is a gram-positibe bacterium or recombinant nucleic acid for use in delivering a product or products such as protein(s), polypeptide(s) or peptide(s) to a subject comprising administering the gram-positive bacterium or recombinant nucleic acid as taught herein to the subject, wherein the one or more exogenous genes encodes said product or products. Preferably said product or products may have a therapeutic or preventive effect in the subject.

[0057] Advantageously for in situ delivery of the present gram-positive bacterium to subjects, the bacterium more closely retains its endogenous character by not introducing or introducing less exogenous or even pathogenic sequences besides the sequences for the exogenous expression products. Thereby, the regulatory GRAS or "Generally Recognized As Safe" status is maintained as much as possible, thus facilitating the process of acquiring clinical approval or market authorisation for the use of the engineered strains in humans or animals.

[0058] The above and further aspects and preferred embodiments of the invention are described in the following sections and in the appended claims. The subject matter of appended claims is hereby specifically incorporated in this specification.

BRIEF DESCRIPTION OF FIGURES



[0059] 

Figure 1: Coomassie blue staining of cellular proteins of a Lactococcus lactis ssp. Cremoris strain MG1363 end-log culture. Prominent protein bands are indicated 1 to 12.

Figure 2: Representation of a reference, monocistronic expression construct (top, sAGX0090) and polycistronic (bicistronic, dual cistron) construct according to an embodiment of the invention (bottom) whereby gene X represents an endogenous gene. Both expression constructs are intended for the expression of β-glucuronidase from the E. coli uidA gene, serving here as an exemplary exogenous gene.

Figure 3: Relative β-glucuronidase (GUS)-activity in a reference host (monocistronic: PhIIA>>uidA, sAGX0090) and in a host comprising a polycistronic (bicistronic) construct according to an embodiment of the invention (endogenous gene X>>rpmD>>uidA), organized as in figure 2. The endogenous genes X are, in this example, usp45, enoA, rplS, rpmB, pyk and gapB. In this example, the rpmD intergenic region provides transcriptional coupling of the endogenous and the exogenous gene. The exogenous E.coli uidA gene encodes β-glucuronidase. All expression constructs are embedded in the bacterial chromosome. The monocistronic construct is present in the thyA locus, bicistronic constructs are embedded at the native position of geneX. The data show that all bicistronic constructs have b-galactosidase activity superior to the monocistronic PhIIA>>uidA construct.

Figure 4: Quantification of human pro-insulin (ins) secretion by Lactococcus lactis in a reference host (sAGX0122) and hosts according to an embodiment of the invention (sAGX0121 and sAGX0164). (A) Schematic overview of ins expression modules. Strain sAGX0122 carries a monocistronic expression construct in which the thyA promoter drives the expression of a secretion leader - human pro-insulin fusion (SS::ins), embedded in the Lactococcus lactis MG1363 chromosome at the thyA locus. Bicistronic expression constructs in sAGX0121 and sAGX0164 consist of a transcriptional coupling of the endogenous usp45 and enoA respectively with SS::ins, through the rpmD intergenic region. These constructs are located on the Lactococcus lactis MG1363 chromosome at the native positions of the usp45 and enoA genes respectively. (B) Levels of pro-insulin detected in the supernatants of the various strains. Strain codes (sAGX0122, sAGX0121 and sAGX0164) are indicated underneath the columns respectively indicating human pro-insulin levels in the supernatants of these strains. The data show that strains carrying both bicistronic constructs have human pro-insulin levels superior to the strain carrying the monocistronic PthyA>>ins construct.

Figure 5: cA2 anti-TNF Fab expression in Lactococcus lactis. Genes encoding VLCL (L) and VHCH1 (H) fragments were transcriptionally coupled by rpmD, rplB, rpsG, rpsE and rplN intergenic regions. Constructs were made in which either L or H are positioned as the first gene of the bicistronic construct. All anti-TNF expression constructs were plasmid borne and placed under the control of the PthyA promoter. Anti-TNF activity was measured in the supernatants of the various strains. The data show that there is higher anti-TNF activity in all constructs where H is the first gene of the bicistronic construct.

Figure 6: CDP870 anti-TNF Fab expression in Lactococcus lactis. (A) CDP870 light and heavy chain fusions to usp45 secretion leader encoding sequences (SS::CDP870 VLCL and SS::CDP870 VHCH1) were inserted as a second and third cistron downstream from usp45 (sAGX0219, sAGX0220) in the Lactococcus lactis MG1363 chromosome. In sAGX0219 and sAGX0220, rpmD was used to couple SS::CD870 genes to usp45. To avoid genetic instability, light and heavy chain genes were coupled through the intergenic region preceding rplN. In sAGX0219, the light chain gene precedes the heavy chain gene, while in sAGX0220, the heavy chain gene precedes the light chain gene. (B) Quantification of anti-human TNF activity in crude culture supernatants. Both heavy chain and light chains were highly expressed by the dual cistron constructs, leading to high levels of functional CDP870 anti-TNF Fab. CDP870 anti-TNF expression substantially increased when the heavy chain was positioned before the light chain.

Figure 7: Quantification of human trefoil factor-1 (hTFF1) secretion by Lactococcus lactis in a reference host (sAGX0085) and a host according to an embodiment of the invention (sAGX0276). (A) Schematic overview of hTFF1 expression modules. Strain sAGX0085 carries a monocistronic expression construct in which the PhllA promoter drives the expression of a secretion leader - hTFF1 fusion (SS::hTFF1), embedded in the Lactococcus lactis MG1363 chromosome at the thyA locus. The bicistronic expression construct in sAGX0276 consist of a transcriptional coupling of gapB with SS::hTFF1, through the rpmD intergenic region. This construct is located on the Lactococcus lactis MG1363 chromosome at the native positions of the gapB gene. (B) Levels of hTFF1 detected in the supernatants of the various strains. Strain codes (sAGX0085 and sAGX0276) are indicated underneath the columns respectively indicating human hTFF1 levels in the supernatants of these strains. The data show that sAGX0276, carrying the bicistronic construct produces hTFF1 levels superior to sAGX0085 which holds the monocistronic construct.

Figure 8: Coomassie blue staining of cellular proteins of a Enterococcus faecium strain LMG 15709 end-log culture. Prominent protein bands are indicated 1 to 12.

Figure 9: Representation of polycistronic (bicistronic, dual cistron) constructs according to an embodiment of the invention whereby gene X represents an endogenous gene. Expression constructs are intended for the expression of β-glucuronidase from the E. coli uidA gene, serving here as an exemplary exogenous gene. Gap and eno are representative "fist" endogenous genes.

Figure 10: Relative β-glucuronidase (GUS)-activity in a reference host (monocistronic: PhIIA>>uidA, sAGX0090) and in a host comprising a polycistronic (bicistronic) construct according to an embodiment of the invention (endogenous gene X>>rpmD>>uidA), organized as in figure 9. The endogenous genes X are, in this example, gapB and eno. In this example, the rpmD intergenic region provides transcriptional coupling of the endogenous and the exogenous gene. The exogenous E.coli uidA gene encodes β-glucuronidase. All expression constructs are embedded in the bacterial chromosome. The monocistronic construct is present in the thyA locus, bicistronic constructs are embedded at the native position of geneX. The data show that all bicistronic constructs have β-galactosidase activity superior to the monocistronic PhIIA>>uidA construct.

Figure 11: Quantification of human interleukin-10 (hIL-10) secretion by Enterococcus faecium in a reference host (sAGX0270) and a host according to an embodiment of the invention (sAGX0279). (A) Schematic overview of hIL-10 expression modules. Bicistronic expression construct in sAGX0279 consists of a transcriptional coupling of the endogenous gap with SS::hIL10, through the rpmD intergenic region. (B) Levels of hIL-10 detected in the supernatants of the various strains.

Figure 12: Quantification of human interleukin-27 (hIL-27) secretion by Enterococcus faecium in a reference host (sAGX0270) and a host according to an embodiment of the invention (sAGX0317). (A) Schematic overview of hIL-27 expression modules. Bicistronic expression construct in sAGX0317 consists of a transcriptional coupling of the endogenous gap with SS::hIL27, through the rpmD intergenic region. (B) Levels of hIL-27 detected in the supernatants of the various strains.

Figure 13: CDP870 anti-TNF Fab expression in Enterococcus faecium. (A) CDP870 light and heavy chain fusions to usp45 secretion leader encoding sequences (SS::CDP870 VHCH1 and SS::CDP870 VLCL) were inserted as a second and third cistron downstream from gap (sAGX0278). To avoid genetic instability, light and heavy chain genes were coupled through the intergenic region preceding rpmD from Lactococcus lactis (LL), whereas rpmD from Enterococcus faecium (EF) was used to couple gap and heavy chain genes. (B) Quantification of anti-human TNF activity in crude culture supernatants. Both heavy chain and light chains were highly expressed by the dual cistron constructs, leading to high levels of functional CDP870 anti-TNF Fab.

Figure 14: Effect of anti-hTNF producing L.lactis bacteria (sAGX0220) on hTNF-induced toxicity and inflammatory cytokine production in A20IEC-KO mice. (a) A20IEC-KO mice (n = 5 per group) were pretreated with vehicle, sAGX0220 or MG1363 1 hour before injection with 2µg (left panel) and 6µg (right panel) of recombinant hTNF and body temperature was followed in time. One group of A20IEC-KO mice was injected with Remicade prior to injection with 6 µg hTNF. (b) MCP-1 levels in ileum, proximal colon and serum 5 h after injection with 2 µg of hTNF. (c) KC and IL-6 levels in ileal homogenates 5 h after injection with 2 µg hTNF. (d) MCP-1 levels in ileum, proximal colon and serum 5h after injection with 6 µg of hTNF. (e) KC and IL-6 levels in ileal homogenates 5h after injection with 6 µg of hTNF. Error bars represent SEM. *, p < 0.05.

Figure 15: CDP870 production in strains according to an embodiment of the invention. (A) CDP870 heavy chain and light chain integrated in the usp45 locus, the enoA locus or the gapB locus. (B) Western blot analysis indicating CDP870 expression in different strains according to an embodiment of the invention. (C) and (D) ELISA analysis indicating CDP870 expression in different strains according to an embodiment of the invention. (E) TNF neutralizing activity of different strains according to an embodiment of the invention.

Figure 16: Survival of Tg1278 mice with induced TNBS colitis after treatment with a strain according to an embodiment of the invention (anti-hTNF-secreting L. lactis strain sAGX0309) in comparison with mice treated with a wild type L. lactis strain and mice treated with Cimzia.

Figure 17: Body weight evolution of Tg1278 mice with induced TNBS colitis after treatment with a strain according to an embodiment of the invention (anti-hTNF-secreting L. lactis strain sAGX0309) in comparison with mice treated with a wild type L. lactis strain and mice treated with Cimzia. Top panel: absolute body weight (g); bottom panel: body weight relative to starting body weight (%).

Figure 18: Histological score of colon tissue of Tg1278 mice with induced TNBS colitis after treatment with a strain according to an embodiment of the invention (anti-hTNF-secreting L. lactis strain sAGX0309) in comparison with mice treated with a wild type L. lactis strain and mice treated with Cimzia. Mean values are indicated above bars. Survival rate is indicated per group.

Figure 19: Proinflammatory cytokine secretion in Tg1278 mice with induced TNBS colitis after treatment with a strain according to an embodiment of the invention (anti-hTNF-secreting L. lactis strain sAGX0309) in comparison with healthy mice, mice treated with a wild type L. lactis strain and mice treated with Cimzia. (A), (B), and (C) represent mIL6, mKC, and mMCP1 levels in pg/mg in the distal colon, respectively.


DETAILED DESCRIPTION OF THE INVENTION



[0060] As used herein, the singular forms "a", "an", and "the" include both singular and plural referents unless the context clearly dictates otherwise.

[0061] The terms "comprising", "comprises" and "comprised of" as used herein are synonymous with "including", "includes" or "containing", "contains", and are inclusive or open-ended and do not exclude additional, non-recited members, elements or method steps. It will be appreciated that the terms "comprising", "comprises" and "comprised of" as used herein comprise the terms "consisting of", "consists" and "consists of", as well as the terms "consisting essentially of", "consists essentially" and "consists essentially of".

[0062] The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within the respective ranges, as well as the recited endpoints.

[0063] The term "about" or "approximately" as used herein when referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of +/-20% or less, preferably +/-10% or less, more preferably +/-5% or less, and still more preferably +/-1% or less of and from the specified value, insofar such variations are appropriate to perform in the disclosed invention. It is to be understood that the value to which the modifier "about" or "approximately" refers is itself also specifically, and preferably, disclosed.

[0064] Whereas the terms "one or more" or "at least one", such as one or more or at least one member(s) of a group of members, is clear per se, by means of further exemplification, the term encompasses inter alia a reference to any one of said members, or to any two or more of said members, such as, e.g., any ≥3, ≥4, ≥5, ≥6 or ≥7 etc. of said members, and up to all said members.

[0065] Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included to better appreciate the teaching of the present invention.

[0066] In the following passages, different aspects of the invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.

[0067] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the appended claims, any of the claimed embodiments can be used in any combination.

[0068] In the following detailed description of the invention, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration only of specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilised and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

[0069] Standard reference works setting forth the general principles of recombinant DNA technology include Molecular Cloning: A Laboratory Manual, 2nd ed., vol. 1-3, ed. Sambrook et al., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., 1989; Current Protocols in Molecular Biology, ed. Ausubel et al., Greene Publishing and Wiley-Interscience, New York, 1992 (with periodic updates) ("Ausubel et al. 1992"); Innis et al., PCR Protocols: A Guide to Methods and Applications, Academic Press: San Diego, 1990. General principles of microbiology are set forth, for example, in Davis, B. D. et al., Microbiology, 3rd edition, Harper & Row, publishers, Philadelphia, Pa. (1980).

[0070] Described herein is a gram-positive bacterium comprising an endogenous gene to which one or more exogenous genes are transcriptionally or translationally coupled. Preferably, the one or more exogenous genes are transcriptionally or translationally coupled downstream (i.e. at the 3' end) of the endogenous gene. The invention provides a gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising an endogenous gene and one or more exogenous genes, wherein said endogenous gene and said one or more exogenous genes are transcriptionally controlled by a promoter endogenous to the gram-positive bacterium, wherein said promoter is
  1. (i) a ribosomal gene promoter selected from the group consisting of:

    (a) an rpmD promoter,

    (b) an rpsD promoter,

    (c) an rpsL promoter,

    (d) an rpsG promoter,

    (e) an rpIR promoter,

    (f) an rpsE promoter,

    (g) an rpsK promoter,

    (h) an rplJ promoter,

    (i) an rplL promoter,

    (j) an rpsB promoter,

    (k) an rplD promoter,

    (I) an rplW promoter,

    (m) an rplB promoter,

    (n) an rplO promoter,

    (o) an rplK promoter,

    (p) an rpsH promoter,

    (q) an rpsM promoter,

    (r) an rpsS promoter,

    (s) an rplU promoter,

    (t) an rplV promoter,

    (u) an rplP promoter

    (v) an rplN promoter,

    (w) an rpsJ promoter,

    (x) an rplX promoter,

    (y) an rplE promoter,

    (z) an rplF promoter, and

    (aa) an rplM promoter;

  2. (ii) a glycolysis gene promoter promoter selected from the group consisting of:
    1. (a) an fbaA promoter, and
    2. (b) a pgk promoter; or
  3. (iii) a dpsA promoter
of said gram-positive bacterium. Preferably, the polycistronic expression unit consecutively comprises one or more endogenous genes and one or more exogenous genes. A further aspect provides a recombinant nucleic acid comprising a polycistronic expression unit comprising a gene endogenous to a gram-positive bacterium to which one or more genes exogenous to the gram-positive bacterium are transcriptionally or translationally coupled, wherein said endogenous gene and said one or more exogenous genes are transcriptionally controlled by a promoter endogenous to the gram-positive bacterium, wherein said promoter is
  1. (i) a ribosomal gene promoter selected from the group consisting of:

    (a) an rpmD promoter,

    (b) an rpsD promoter,

    (c) an rpsL promoter,

    (d) an rpsG promoter,

    (e) an rpIR promoter,

    (f) an rpsE promoter,

    (g) an rpsK promoter,

    (h) an rplJ promoter,

    (i) an rplL promoter,

    (j) an rpsB promoter,

    (k) an rplD promoter,

    (I) an rplW promoter,

    (m) an rplB promoter,

    (n) an rplO promoter,

    (o) an rplK promoter,

    (p) an rpsH promoter,

    (q) an rpsM promoter,

    (r) an rpsS promoter,

    (s) an rplU promoter,

    (t) an rplV promoter,

    (u) an rplP promoter

    (v) an rplN promoter,

    (w) an rpsJ promoter,

    (x) an rplX promoter,

    (y) an rplE promoter,

    (z) an rplF promoter, and

    (aa) an rplM promoter;

  2. (ii) a glycolysis gene promoter promoter selected from the group consisting of:
    1. (a) an fbaA promoter, and
    2. (b) a pgk promoter; or
  3. (iii) a dpsA promoter
of said gram-positive bacterium. Preferably, the one or more exogenous genes are transcriptionally or translationally coupled downstream (i.e. at the 3' end) of the endogenous gene.

[0071] Preferably, one of the said exogenous gene(s) is the most 3' gene of the polycistronic expression unit, i.e. the one exogenous gene is the last or most downstream gene of the polycistronic expression unit. For instance if the endogenous gene is monocistronic, the one or more exogenous gene is located after or downstream (i.e. at the 3' end) of - and transcriptionally coupled with - the open reading frame of the gene. Likewise, if the endogenous gene is itself polycistronic, such as (part of) an operon, the one of said exogenous genes is located after or downstream (i.e. at the 3' end) of the last (i.e. most downstream or most 3') endogenous gene of the endogenous polycistronic gene.

[0072] Most preferably, the endogenous gene as referred to herein throughout the description is monocistronic. The endogenous gene preferably thus does not form part of an endogenous operon.

[0073] Described herein is a polycistronic expression unit effected by a promoter which may be or may exhibit one or more of the following characteristics: constitutive promoters, central metabolism gene promoters, essential gene promoters, strong promoters, housekeeping gene promoters, ribosomal gene promoters, glycolysis gene promoters. Most preferably, the promoter is a constitutive promoter.

[0074] As used herein, the term "gram-positive bacterium" has its common meaning known in the art. By means of further guidance, a gram-positive bacterium can be identified by Gram staining as retaining crystal violet stain.

[0075] In a preferred embodiment, the gram-positive bacterium according to the invention is non-pathogenic in the sense that it does not cause harm or does not lead to deleterious effects when administered to an intended subject.

[0076] Preferably, the gram-positive bacterium according to the invention is a lactic acid bacterium (LAB), including, but not limited to the genera Lactococcus, Lactobacillus, Leuconostoc, Pediococcus, Streptococcus, Aerococcus, Carnobacterium, Enterococcus, Oenococcus, Sporolactobacillus, Tetragenococcus, Vagococcus, and Weisella. More preferably, the LAB is a Lactococcus species, such as, but not limited to Lactococcus lactis, Lactococcus garvieae, Lactococcus piscium, Lactococcus plantarum and Lactococcus raffinolactis, and any subspecies and strains thereof. Most preferably, the Lactococcus species is Lactococcus lactis, and any subspecies and strain thereof, such as without limitation Lactococcus lactis ssp. cremoris, Lactococcus lactis ssp. hordniae, Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. bv. diacetylactis. In further preferred embodiments of the invention the Lactococcus lactis is Lactococcus lactis ssp. cremoris or Lactococcus lactis ssp. lactis, more preferably Lactococcus lactis ssp. cremoris, and encompasses any strains thereof, such as, e.g., Lactococcus lactis ssp. cremoris SK11, Lactococcus lactis ssp. cremoris MG1363, or Lactococcus lactis ssp lactis IL1403. In another preferred embodiment, the LAB is an Enterococcus sp., preferably Enterococcus faecalis, Enterococcus faecium and any subspecies and strains thereof, such as, without limitation Enterococcus faecium strain LMG15709.

[0077] In another preferred embodiment, the gram-positive bacterium according to the invention is Bifidobacterium.

[0078] Bifidobacterium is a genus of Gram-positive, non-motile, often branched anaerobic bacteria. Bifidobacteria as used herein may include B. adolescentis, B. angulatum, B. animalis, B. asteroides, B. bifidum, B. boum, B. breve, B. catenulatum, B. choerinum, B. coryneforme, B. cuniculi, B. denticolens, B. dentium, B. gallicum, B. gallinarum, B. indicum, B. infantis, B. inopinatum, B. lactis, B. longum, B. magnum, B. merycicum, B. minimum, B. pseudocatenulatum, B. pseudolongum, B. pullorum, B. ruminantium, B. saeculare, B. subtile, B. suis, B. thermacidophilum, B. thermophilum. Preferably, the Bifidobacterium is B. adolescentis, B. bifidum, B. breve, B. infantis, B. longum. It is to be understood that all subspecies and strains of Bifidobacteria are also included.

[0079] As used herein, the term "consecutively" in the context of endogenous and exogenous genes refers to the 5' to 3' order of the respective genes in a polynucleic acid, vector or chromosome. For example, a polycistronic expression unit consecutively comprising one or more endogenous genes and one or more exogenous genes relates to a unit in which the one or more endogenous genes are positioned upstream of the one or more exogenous genes. Hence the one or more exogenous genes are positioned after the 3' end of the one or more endogenous genes. It is to be understood that the consecutive coupling or ordering as described herein does not necessarily imply a direct coupling of the endogenous and exogenous gene. Additional sequences may be present between the endogenous and exogenous gene. As an example, an intergenic region as defined further herein may be present between (i.e. downstream or 3' of the endogenous gene and upstream or 5' of the exogenous gene) the consecutive endogenous and exogenous genes. As used herein, the terms "endogenous gene", "endogenous promoter", "endogenous intergenic region", "endogenous ribosome binding site" refer to respectively a gene, promoter, intergenic region or ribosome binding site which are native to a gram-positive bacterium, or can be found in nature in a gram-positive bacterium. As such, the term endogenous gene, promoter, intergenic region or ribosome binding site encompasses orthologous genes, promoters, intergenic regions, and ribosome binding sites between different genera, species, subspecies or strains of gram-positive bacteria. In particular, a gene, promoter, intergenic region or ribosome binding site isolated from one genus, species, subspecies, or strain of gram-positive bacteria is said to be endogenous for all other genera, species, subspecies, or strains of gram-positive bacteria, irrespective of possible polynucleic acid sequence differences, provided said other genus, species, subspecies, or strain of gram-positive bacteria in nature also comprises such gene, promoter, intergenic region or ribosome binding site. Thus, such divergent but found-in-nature gene, promoter, intergenic region, or ribosome binding site sequences would be considered endogenous. By means of example, and without limitation, the gene encoding enolase, enoA, which is isolated from Lactococcus lactis ssp. lactis is also considered endogenous in respect of Lactococcus lactis ssp. cremoris.

[0080] Preferably, however, an "endogenous" gene, promoter or intergenic region of a given genus, species, subspecies or strain of gram-positive bacterium as intended herein may denote a gene, promoter or intergenic region which is found in nature in, i.e., is native to or own to, that same genus, species, subspecies or strain of gram-positive bacterium, respectively. By means of example, and without limitation, the gene encoding enolase, enoA, which is isolated from Lactococcus lactis ssp. lactis may preferably be considered "endogenous" to Lactococcus lactis ssp. lactis, but not to Lactococcus lactis ssp. cremoris.

[0081] As used herein, the term "exogenous gene" refers to a gene which is not native to a gram-positive bacterium, or cannot be found in nature in a gram-positive bacterium. The term exogenous gene is synonymous with the term heterologous gene. The exogenous gene may be a full length gene or may alternatively be a truncated gene or a gene fragment. By means of example, a exogenous gene can be derived from viruses, other prokaryotes, such as a gram-negative bacterium, or alternatively and preferably can be derived from eukaryotes, such as plants, animals, preferably mammals, most preferably human. Alternatively, the exogenous gene can be completely or partially synthetic or artificial, in the sense that it completely or partially does not occur in nature. In addition, the exogenous gene can be chimeric, in the sense that it can be composed of sequences originating from different species or a combination of naturally occurring and synthetic or artificial sequences. Also encompassed are chimeric sequences composed of gram-positive bacterial sequences and sequences exogenous of gram-positive bacteria, such as for instance sequences encoding fusion proteins composed of gram-positive bacterial secretion signal peptides and exogenous proteins.

[0082] As eukaryotic genes for the most part comprise introns beside exons, the skilled person will appreciate that according to the invention, any reference to a exogenous gene relates to the intron-less open reading frame of such gene, i.e., the protein-coding sequence of such gene. The term "open reading frame" or ORF refers to a succession of coding nucleotide triplets starting with a translation initiation codon (e.g. ATG or GTG) and closing with a translation termination codon (e.g., TAA, TAG or TGA) and encoding a single polypeptide.

[0083] Prokaryotic genes, in particular genes from gram-positive bacteria do not comprise introns. Hence, the coding sequence or open reading frame of a prokaryotic gene corresponds to the succession of coding nucleotide triplets starting with a translation initiation codon and closing with a translation termination codon as located on the prokaryotic genome, in particular the bacterial chromosome.

[0084] Accordingly, in an aspect, the invention relates to a gram-positive bacterium comprising an endogenous open reading frame or coding sequence to which one or more exogenous open reading frame or coding sequences are transcriptionally or translationally coupled.

[0085] The skilled person will understand that, whereas the term "gene" in general may refer to a locatable region of genomic sequence, corresponding to a unit of inheritance, which is associated with transcriptional and translational regulatory regions such as the pribnow box, shine-dalgarno sequence, operators, terminators, transcribed regions, and or other functional sequence regions, any reference to the term "gene" in the context of exogenous sequences as described herein preferably refers to the coding sequence or open reading frame of that gene, unless explicitly stated to the contrary. Any reference to the term "gene" in the context of endogenous sequences as described herein may refer to a locatable region of genomic sequence, corresponding to a unit of inheritance, which is associated with regulatory regions, transcribed regions, and or other functional sequence regions, but alternatively may also refer to the coding sequence or open reading frame of that gene.

[0086] As used herein, the term "translationally coupled" is synonymous with "translationally linked" or "translationally connected". These terms in essence relate to polycistronic expression systems or units. Two or more genes, open reading frames or coding sequences are said to be translationally coupled when common regulatory element(s) such as in particular a common promoter effects the transcription of said two or more genes as one mRNA encoding said two or more genes, open reading frames or coding sequences, which can be subsequently translated into two or more individual polypeptide sequences. The skilled person will appreciate that bacterial operons are naturally occurring polycistronic expression systems or units in which two or more genes are translationally or transcriptionally coupled. According to the invention, transcriptional coupling underlies translational coupling.

[0087] The gram-positive bacterium of the invention comprises an endogenous gene to which one or more exogenous genes, open reading frame or coding sequence are transcriptionally coupled. Preferably, the gram-positive bacterium consecutively comprises an endogenous gene to which one or more exogenous genes, open reading frame or coding sequence are transcriptionally coupled. As used herein, the term "transcriptionally coupled" is synonymous with "transcriptionally connected" and "transcriptionally linked". These terms generally refer to polynucleic acid sequences comprising two or more open reading frames or coding sequences which are commonly transcribed as one mRNA, and which can be translated into two or more individual polypeptides.

[0088] Described herein is a gram-positive bacterium or recombinant nucleic acid comprising a polycistronic expression unit, said polycistronic expression unit comprising an endogenous gene and one or more exogenous genes, open reading frame or coding sequence.

[0089] As used herein, the term "polycistronic expression unit" or "polycistronic expression system" refers to a unit wherein the expression of two or more genes is regulated by common regulatory mechanisms, such as promoters, operators, and the like. The term polycistronic expression unit as used herein is synonymous with multicistronic expression unit. Examples of polycistronic expression units are without limitation bicistronic, tricistronic, tetracistronic expression units. Any mRNA comprising two or more, such as 3, 4, 5, 6, 7, 8, 9, 10, or more, open reading frames or coding regions encoding individual expression products such as proteins, polypeptides and/or peptides is encompassed within the term polycistronic.

[0090] The polycistronic expression unit or system as described herein is transcriptionally controlled by a promoter which is endogenous to the gram positive bacterium.

[0091] By "promoter" is meant generally a region on a nucleic acid molecule, preferably DNA molecule, to which an RNA polymerase binds and initiates transcription. A promoter is preferably, but not necessarily, positioned upstream, i.e., 5', of the sequence the transcription of which it controls.

[0092] Described herein are translationally or transcriptionally coupled one or more endogenous genes and one or more exogenous genes transcriptionally controlled by the native promoter of (one of) said one or more endogenous genes. The polycistronic expression unit or system as described herein may be transcriptionally controlled by the native promoter of (one of) said one or more endogenous genes comprised in said polycistronic expression system or unit or the polycistronic expression unit or system as described herein may be operably linked to a gram-positive endogenous promoter.

[0093] As used herein, the term "operably linked" or "operable linkage" is a linkage in which the regulatory DNA sequences and the DNA sequence sought to be expressed are connected in such a way as to permit expression. For example, a promoter is said to be operably linked to a gene, open reading frame or coding sequence, if the linkage or connection allows or effects transcription of said gene. In a further example, a 5' and a 3' gene, cistron, open reading frame or coding sequence are said to be operably linked in a polycistronic expression unit, if the linkage or connection allows or effects translation of at least the 3' gene.

[0094] For example, DNA sequences, such as, e.g., preferably a promoter and an open reading frame, are said to be operably linked if the nature of the linkage between the sequences does not (1) result in the introduction of a frame-shift mutation, (2) interfere with the ability of the promoter to direct the transcription of the open reading frame, or (3) interfere with the ability of the open reading frame to be transcribed by the promoter region sequence.

[0095] In an exemplary preferred embodiment, the promoter may be positioned upstream of, i.e., 5' of, the open reading frame(s) to which it is operably linked.

[0096] The skilled person will appreciate that the promoter may be associated with additional native regulatory sequences or regions, e.g. operators. The precise nature of the regulatory regions needed for expression may vary from organism to organism, but shall in general include a promoter region which, in prokaryotes, contains both the promoter (which directs the initiation of RNA transcription) as well as the DNA sequences which, when transcribed into RNA, will signal the initiation of protein synthesis. Such regions will normally include those 5'-non-coding sequences involved with initiation of transcription and translation, such as the Pribnow-box (cf. TATA-box), Shine-Dalgarno sequence, and the like.

[0097] In a further embodiment, the promoter is the native promoter of the 5' most, i.e., most upstream, endogenous gene in the polycistronic expression unit.

[0098] As used herein, the term "constitutive" in the context of a promoter (or by extension relating to gene expression of the endogenous gene) refers to a promoter that allows for continual transcription of its associated gene. In particular, transcription of the associated gene or genes under control of such promoter occurs independently of any inducer or other regulatory signal.

[0099] As used herein, the term "housekeeping gene" or "housekeeping promoter" refers to a gene or a promoter of a gene that is required for the maintenance of basic cellular function. Although some housekeeping genes are expressed at relatively constant levels, other housekeeping genes may vary depending on external or experimental conditions. Housekeeping genes may for instance be involved in metabolism, gene expression (such as basal transcription machinery), signalling, but may also be structural genes.

[0100] As used herein, "glycolysis gene" or "glycolysis promoter" refers to a gene or promoter of a gene involved in the glycolytic pathway, and include the promoters of the genes encoding glycolytic enzymes, particularly hexokinase, phosphoglucose isomerase, phosphofructokinase, fructose bisphosphate aldolase, triosephosphate isomerase, glyceraldehyde phosphate dehydrogenase, phosphoglycerate kinase, phosphoglycerate mutase, enolase, and pyruvate kinase.

[0101] As used herein, "ribosomal gene" or "ribosomal promoter" refers to a gene or promoter of a ribosomal gene, including genes encoding ribosomal proteins as well as genes transcribed into ribosomal RNA. Preferably, it may refer to a gene or promoter of a ribosomal protein.

[0102] As used herein, "central metabolism gene" or "central metabolism promoter" or alternatively "basic metabolism gene" or "basic metabolism promoter" refers to a gene or promoter of a gene involved in critical metabolic pathways, and includes genes involved in glycolysis, pentose-phosphate pathway, and tricaboxylic acid (TCA) cycle.

[0103] As used herein, the term "essential" in the context of a gene (or by extension relating to the promoter of such gene) relates to a gene the absence of the native expression product of which is detrimental, such as in particular lethal, for the host or alternatively alters, inhibits or prevents, normal physiology or function, such as in particular propagation or growth. It is to be understood that, as used herein, the term "essential" in the context of a gene or promoter of a gene relates to constitutively essential, as opposed to conditionally essential. For instance, the genes of the lactose operon, such as the beta-galactosidase gene, in several gram-positive bacteria, in particular lactic acid bacteria such as Lactococcus sp. may be essential when the bacteria are cultivated in a medium containing lactose as the main or sole carbon source, these genes are not essential when the bacteria are cultivated in a medium containing alternative carbon sources. These genes are therefore only conditionally essential, but not constitutively essential, as intended herein.

[0104] As described herein, the endogenous promoter and/or the endogenous gene as may be selected from the group comprising or consisting of gram-positive bacterial promoters and/or genes corresponding to the following Lactococcus promoters and/or genes, more particularly Lactococcus lactis ssp. cremoris strain MG1363 promoters and/or genes: 1) DNA-directed RNA polymerase, beta' subunit / 160 kD subunit (rpoC), 2) DNA-directed RNA polymerase, beta subunit / 140 kD subunit (rpb2 or rpoB), 3) DNA-binding ferritin-like protein (oxidative damage protectant) (dps), 4) pyruvate kinase (pyk), 5) glutamyl- and glutaminyl-tRNA synthetases (glnS or gltX), 6) enolase (eno), 7) glutamine synthetase (glnA) 8) HTH-type transcriptional regulator (glnR), 9) Xaa-His dipeptidase (argE or pepV), 10) FOF1-type ATP synthase beta subunit (ATP synthase F1 beta subunit) (atpD), 11) 3-phosphoglycerate kinase (pgk), 12) glyceraldehyde-3-phosphate dehydrogenase / erythrose-4-phosphate dehydrogenase (gapA or gapB), 13) acetate kinase (ackA), 14) 3-oxoacyl-(acyl-carrier-protein) synthase (fabB or fabF), 15) 3-oxoacyl-(acyl-carrier-protein) reductase (fabG), 16) DNA-directed RNA polymerase, alpha subunit / 40 kD subunit (rpoA), 17) Xaa-Pro aminopeptidase (pepP), 18) fructose / tagatose bisphosphate aldolase (tbp or fbaA), 19) ribosomal protein S4 (rpsD), 20) superoxide dismutase (sodA), 21) ribosomal protein S12 (rpsL) and ribosomal protein S7 (rpsG), 22) ribosomal protein L18 (rpIR) and ribosomal protein S5 (rpsE) and ribosomal protein L30/L7E (rpmD), 23) S-ribosylhomocysteine lyase (luxS), 24) ribosomal protein L19 (rplS), 25) ribosomal protein S11 (rpsK), 26) ribosomal protein L10 (rplJ), 27) ribosomal protein L7/L12 (rplL), 28) bacterial nucleoid DNA-binding protein / DNA binding protein HU (hup or hllA), 29) 50S ribosomal protein L28 (rpmB), 30) phosphotransferase system cellobiose-specific component IIB (lace or ptcB), 31) FOF1-type ATP synthase alpha subunit (atpA), 32) ABC-type sugar transport system (ATPase component) (malK or msmK), 33) acetoin dehydrogenase complex E1 component alpha subunit (acoA or pdhA), 34) cell division protein (diflVA or ftsA), 35) UDP-galactopyranose mutase (glf), 36) glutamyl aminopeptidase (frvX or pepA), 37) predicted dehydrogenase related protein (mviM or llmg_0272), 38) ribosomal protein S2 (rpsB), 39) translation initiation factor 3 (IF-3) (infC), 40) ribosomal protein L4 (rplD) and ribosomal protein L23 (rplW) and ribosomal protein L2 (rplB), 41) EMAP domain (ydjD), 42) transcription elongation factor (greA), 43) protease subunit of ATP-dependent Clp protease (clpP), 44) ribosomal protein L15 (rplO), 45) ribosomal protein L11 (rplK), 46) ribosomal protein S8 (rpsH), 47) ribosomal protein L21 (rplU), 48) ribosomal protein S13 (rpsM), 49) ribosomal protein S19 (rpsS) and ribosomal protein L22 (rplU or rplV) and ribosomal protein L16 (rplP) and ribosomal protein L14 (rpIN), 50) ribosomal protein S10 (rpsJ), 51) co-chaperonin GroES (Hsp10) (cpn10), 52) ribosomal protein L24 (rplX), 53) hypothetical protein LACR_0137 (duf965), and 54) secreted 45 kDa protein (usp45). The endogenous promoter and/or endogenous gene may be selected from the group comprising or consisting of enoA, usp45, gapB, pyk, rpmB, and rplS. These promoters and their sequences are disclosed for example in WO 2008/08411 e.g., in Table 1 and Figure 1A-H thereof. Described herein is a gram positive bacterium or a recombinant nucleic acid, wherein the endogenous gene and the one or more exogenous genes are transcriptionally controlled by a promoter endogenous to the gram-positive bacterium, selected from the group consisting of the promoter of eno, usp45, gap, pyk, rpmB and rplS of said gram-positive bacterium. In a further embodiment, the endogenous gene is located in its native chromosomal locus in the gram-positive bacterium.

[0105] As described herein, said one or more exogenous genes, open reading frames or coding sequences may be translationally or transcriptionally coupled to the 3' end of said one or more endogenous genes, open reading frame or coding sequence. Accordingly, in an embodiment, the invention provides for a gram-positive bacterium comprising a polycistronic expression unit, wherein said polycistronic expression unit comprises a 5' endogenous gene and one or more 3' exogenous genes. Preferably, the 5' most gene of the polycistronic expression unit is an endogenous gene. By means of example, and without limitation, the polycistronic expression unit may comprise or consist essentially of from 5' end to 3' end an endogenous gene followed by one or more endogenous genes, followed by one or more exogenous genes. Alternatively, and without limitation, the polycistronic expression unit may comprise or consist essentially of from 5' end to 3' end an endogenous gene followed by one or more exogenous genes. Alternatively, the polycistronic expression unit may comprise or consist essentially of from 5' end to 3' end an endogenous gene followed by one or more exogenous genes, followed by one or more endogenous genes.

[0106] The translationally coupled or transcriptionally coupled endogenous gene and one or more exogenous genes, or the polycistronic expression unit or system, as described herein may be comprised in a replicon which allows maintenance and/or propagation and expression of the endogenous and exogenous genes in the gram-positive bacteria according to the invention as described herein.

[0107] In an embodiment, the translationally coupled or transcriptionally coupled endogenous gene and one or more exogenous genes, including the endogenous promoter as described elsewhere in this specification, or the polycistronic expression unit, as described herein may be comprised in a vector, preferably an expression vector allowing expression in gram-positive bacteria. Accordingly, the invention also relates to a vector comprising the recombinant nucleic acid as described herein.

[0108] As used herein, "vector" refers to a nucleic acid molecule, typically DNA, to which nucleic acid fragments may be inserted and cloned, i.e., propagated. Hence, a vector will typically contain one or more unique restriction sites, and may be capable of autonomous replication in a defined host or vehicle organism such that the cloned sequence is reproducible. Vectors may include, without limitation, plasmids, phagemids, bacteriophages, bacteriophage-derived vectors, PAC, BAC, linear nucleic acids, e.g., linear DNA, etc., as appropriate (see, e.g., Sambrook et al., 1989; Ausubel 1992).

[0109] Factors of importance in selecting a particular vector, e.g., a plasmid, include inter alia: the ease with which recipient cells that contain the vector may be recognized and selected from those recipient cells which do not contain the vector; the number of copies of the vector which are desired in a particular host; and whether it is desirable to be able to "shuttle" the vector between host cells of different species. Preferred prokaryotic vectors include plasmids such as those capable of replication in E. coli (such as, for example, pBR322, ColE1, pSC101, pUC19, etc.). Such plasmids are describe in, e.g., Sambrook et al., 1989; Ausubel 1992. Particularly preferred vectors may be those able to replicate in E. coli (or other Gram negative bacteria) as well as in another host cell of interest, such as in a Gram positive bacterium, a lactic acid bacterium, preferably Lactococcus, more preferably Lactococcus lactis (see, e.g., Kok et al. Appl. Environ. Microbiol., 1984, vol. 48(4), 726-31). Other preferred vectors may be those able to replicate and/or shuttle between one or more Gram positive bacteria but not in Gram negative bacteria. In a preferred embodiment, the vector is pT1NX as described by Steidler et al. Appl. Environ. Microbiol., 1995, vol. 61(4), 1627-1629.

[0110] In another embodiment, the transcriptionally coupled endogenous gene and one or more exogenous genes, or the polycistronic expression unit or system, as described herein are integrated in the gram-positive bacterial genome or chromosome. Methods for obtaining recombinant gram-positive bacteria and random as well as homologous recombination are well-known in the art, as well as vectors for effecting recombination. By means of further guidance, such methods and vectors are for instance disclosed in Steidler et al. (2003, Nature Biotechnology, 21:785-789), Law et al. (1995, J Bacteriol, 177(24): 7011-7018), Leenhouts et al. (1998, Methods in Cell Science, 20:35-50) and WO 2004/046346.

[0111] Preferably, the polycistronic expression unit as described herein is generated or introduced by site-directed integration of the requisite sequences in the bacterial chromosome by homologous recombination.

[0112] In an embodiment, a recombination vector comprises an endogenous promoter as described elsewhere in this specification, and optionally additional regulatory sequences, as well as a polycistronic expression unit as described herein. Preferably, the endogenous promoter and the polycistronic expression unit are operably linked. Homologous recombination can be effected at a predetermined locus. Such system is highly modular and allows for individual selection and combination of promoter, regulatory sequences, endogenous gene, and exogenous gene, as well as the choice of insertion site.

[0113] In another embodiment, the gram-positive bacterium according to the invention comprises an endogenous promoter as described elsewhere in this specification at its native locus, i.e., in its native genomic context on the bacterial chromosome, to which a polycistronic expression unit comprising an endogenous gene, open reading frame or coding sequence and one or more exogenous genes, open reading frame or coding sequence are operably linked. The operable linkage can be effected through homologous recombination between the locus comprising the promoter and a recombination vector comprising the polycistronic expression unit, flanked by sequences configured to effect said homologous recombination. Accordingly, in an embodiment, the invention relates to a gram-positive bacterium as described herein, wherein the endogenous gene is transcriptionally coupled to the one or more exogenous genes by chromosomally integrating the one or more exogenous genes to said locus, preferably by chromosomally integrating the one or more exogenous genes 3' of the endogenous gene in said locus.

[0114] Vector design can be chosen such that merely the open reading frame or coding sequences of the endogenous and/or exogenous genes are integrated into the intended chromosomal locus. In this case, the regulatory sequences beside the promoter per se which effect transcription and/or translation, e.g. operators, transcription initiation site, shine-dalgarno sequence, terminator sequence, etc. are provided for by the native genomic locus of the promoter. Alternatively, such sequences may be provided on the recombination vector comprising the polycistronic expression unit. In the latter case, depending on the needs, the native regulatory sequences associated with the endogenous promoter may be removed during homologous recombination. The systems described here are modular in respect of individual selection of endogenous gene, exogenous gene and possibly the regulatory sequences, but predetermine the insertion site at the endogenous locus of the selected promoter.

[0115] In a further embodiment, the gram-positive bacterium according to the invention comprises an endogenous promoter as well as an endogenous gene, both as described elsewhere in this specification, at its (their) native locus, i.e. in its (their) native genomic context on the bacterial chromosome, to which one or more exogenous genes, open reading frame or coding sequence are operably linked, such as to effect polycistronic expression of the one or more endogenous genes and the one or more exogenous genes. In this system, the endogenous promoter and one or more endogenous genes, as well as the regulatory sequences effecting transcription and translation of said one or more endogenous genes is present in their native locus. Such system maximally preserves the native character of the gram-positive bacterium.

[0116] A polycistronic expression unit comprises at least two genes, open reading frames or coding sequences. In order to initiate translation of all genes, each of these genes generally is associated with sequences effecting ribosome binding, i.e. ribosome binding sites. In prokaryotes, ribosome binding sites are denoted Shine-Dalgarno (SD) sequences, which have the general consensus sequence 5'-AGGAGG-3'. The SD sequence on average is located about 8 base pairs upstream (i.e. 5' of) the translation initiation codon or start codon. Depending on the distance (in amount of nucleotides) between the stop codon of the 5' gene and the start codon of the 3' gene, the SD sequences can be typically positioned 1) in an intergenic region between both genes, if the distance is at least the size of the SD sequence; 2) in an intergenic region between both genes, but overlapping with the stop codon of the 5' gene, in case of a smaller distance between 5' and 3' gene; or 3) 5' to the stop codon of the 5' gene, if for instance the stop codon of the 5' gene and the start codon of the 3' gene are very close or overlap.

[0117] In an embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein, further comprising one or more polynucleic acid sequences comprising a ribosome binding site configured to effect translation of the one or more exogenous genes. In another embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein, further comprising one or more ribosome binding site configured to effect translation of the one or more exogenous genes. In a further embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein wherein said one or more endogenous genes and said one or more exogenous genes are transcriptionally or translationally coupled by means of a ribosome binding site. In yet another embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid, comprising a polycistronic expression unit as described herein, wherein any 5' gene is coupled to a 3' gene by a polynucleic acid sequence comprising or consisting (essentially) of a ribosome binding site. In a preferred embodiment, said ribosome binding site is endogenous to a gram-positive bacterium. In a further preferred embodiment, said ribosome binding site is comprised in an intergenic region, preferably an operon intergenic region.

[0118] In another embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein, further comprising one or more polynucleic acid sequences comprising an intergenic region configured to effect translation of the one or more exogenous genes. In a further embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein, further comprising one or intergenic region configured to effect translation of the one or more exogenous genes. In a further embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein wherein said one or more endogenous genes and said one or more exogenous genes are transcriptionally or translationally coupled by means of an intergenic region. In yet another embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid, comprising a polycistronic expression unit as described herein, wherein any 5' gene is coupled to a 3' gene by a polynucleic acid sequence comprising or consisting of an intergenic region. In a preferred embodiment, said intergenic region is endogenous to a gram-positive bacterium. In a further preferred embodiment, said intergenic region is an operon intergenic region.

[0119] As used herein, the term "intergenic region" is synonymous with "intergenic linker" or "intergenic spacer". An intergenic region is defined as a polynucleic acid sequence between adjacent (i.e., located on the same polynucleic acid sequence) genes, open reading frames, cistrons or coding sequences. By extension, the intergenic region can include the stop codon of the 5' gene and/or the start codon of the 3' gene which are linked by said intergenic region. As defined herein, the term intergenic region specifically relates to intergenic regions between adjacent genes in a polycistronic expression unit. For example, an intergenic region as defined herein can be found between adjacent genes in an operon. Accordingly, in an embodiment, the intergenic region as defined herein is an operon intergenic region.

[0120] In an embodiment, the intergenic region, linker or spacer is selected from the group of intergenic regions comprising or consisting of intergenic regions preceding, i.e. 5' to, more particularly immediately 5' to, rplW, rplP, rpmD, rplB, rpsG, rpsE or rplN of a gram-positive bacterium. In an embodiment, said gram positive bacterium is a lactic acid bacterium, preferably a Lactococcus species, more preferably Lactococcus lactis, and any subspecies or strain thereof. In an embodiment, said intergenic region encompasses the start codon of rplW, rplP, rpmD, rplB, rpsG, rpsE or rplN and/or the stop codon of the preceding, i.e. 5', gene. In a preferred embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein, wherein the endogenous gene and the one or more exogenous genes are transcriptionally coupled by intergenic region or regions active in the gram-positive bacterium, preferably wherein the intergenic region or regions is endogenous to said gram-positive bacterium, more preferably wherein the endogenous intergenic region is selected from the group consisting of intergenic regions preceding rplW, rplP, rpmD, rplB, rpsG, rpsE, rplN, rplM, rplE, and rplF.

[0121] The skilled person will appreciate that if the intergenic region encompasses a 5' stop codon and/or a 3' start codon, these respective codons preferably are not present in the genes which are linked by said intergenic regions, in order to avoid double start and/or stop codons, which may affect correct translation initiation and/or termination. Methods for identifying intergenic regions are known in the art. By means of further guidance, intergenic regions can for instance be identified based on prediction of operons, and associated promoters and open reading frames, for which ample software is known and available in the art.

[0122] In a further embodiment, said intergenic region sequence is selected from the group comprising, consisting essentially of or consisting of any of SEQ ID NOs: 1 to 7:
SEQ ID NO: 1 TAATG
SEQ ID NO: 2 TAATCCATG
SEQ ID NO: 3 TAAGGAGGAAAAAATG
SEQ ID NO: 4 TAATAGAGGAGGAAAATCGTG
SEQ ID NO: 5 TAAGAAGGGAGATAAGTAAGAATG
SEQ ID NO: 6 TAAGGAAAGGGGTAATTAAACATG
SEQ ID NO: 7 TAAGCAAAACTAGGAGGAATATAGCATG


[0123] In a further embodiment, said intergenic region sequence is selected from the group comprising, consisting essentially of or consisting of sequences displaying one mismatch or a deletion or insertion of one nucleotide vs. SEQ ID NO: 1 or SEQ ID NO: 2, sequences displaying one, two or three mismatches, or a deletion or insertion of one, two or three nucleotides vs. SEQ ID NO: 3 or SEQ ID NO: 4, and sequences displaying one, two, three or four mismatches or a deletion or insertion of one, two, three or four nucleotides vs. SEQ ID NO: 5, SEQ ID NO: 6 or SEQ ID NO: 7.

[0124] SEQ ID NOs: 1 to 7 all comprise a 5' stop codon and a 3' start codon. SEQ ID NOs: 1 to 7 correspond to the intergenic regions preceding, respectively, rplW, rplP, rpmD, rplB, rpsG, rpsE and rplN of Lactococcus lactis ssp. cremoris strain MG1363 (Genbank accession number AM406671.1). These sequences are among other identical to the corresponding sequences of Lactococcus lactis ssp. lactis strain CV56 (Genbank accession number CP002365.1), Lactococcus lactis ssp. cremoris strain NZ9000 (Genbank accession number CP002094.1), Lactococcus lactis ssp. lactis strain KF147 (Genbank accession number CP001834.1), Lactococcus lactis ssp. lactis strain IL1403 (Genbank accession number AE005176.1), and Lactococcus lactis ssp. cremoris strain SK11 (Genbank accession number CP000425.1).

[0125] In another embodiment, the intergenic region, linker or spacer is selected from the group of intergenic regions comprising or consisting of intergenic regions preceding, i.e. 5' to, more particularly immediately 5' to, rplP, rpmD, rplM, rpsE, rplE, or rplF of a gram-positive bacterium. In an embodiment, said gram positive bacterium is a lactic acid bacterium, preferably an Enterococcus species, more preferably Enterococcus faecium, and any subspecies or strain thereof. In an embodiment, said intergenic region encompasses the start codon of rplP, rpmD, rplM, rpsE, rplE, or rplF and/or the stop codon of the preceding, i.e. 5', gene. The skilled person will appreciate that if the intergenic region encompasses a 5' stop codon and/or a 3' start codon, these respective codons preferably are not present in the genes which are linked by said intergenic regions, in order to avoid double start and/or stop codons, which may affect correct translation initiation and/or termination. Methods for identifying intergenic regions are known in the art. By means of further guidance, intergenic regions can for instance be identified based on prediction of operons, and associated promoters and open reading frames, for which ample software is known and available in the art.

[0126] In a further embodiment, said intergenic region sequence is selected from the group comprising, consisting essentially of or consisting of any of SEQ ID NOs: 8 to 13:
SEQ ID NO: 8 TAATC
SEQ ID NO: 9 TAAGGAGGACAACAATA
SEQ ID NO: 10 TAATAGGAGGGAATTTCA
SEQ ID NO: 11 TTAGAAGAAGGAGGAATACCATTC
SEQ ID NO: 12 TAAAAGTTTAAGGAAGGAGGGTCTTACTGA
SEQ ID NO: 13 TAATCAAGTAGAATCTACAAGGAGGTGTCTTTAA


[0127] In a further embodiment, said intergenic region sequence is selected from the group comprising, consisting essentially of or consisting of sequences displaying one mismatch or a deletion or insertion of one nucleotide vs. SEQ ID NO: 8, sequences displaying one, two or three mismatches, or a deletion or insertion of one, two or three nucleotides vs. SEQ ID NO: 9 or SEQ ID NO: 10 and sequences displaying one, two, three or four mismatches or a deletion or insertion of one, two, three or four nucleotides vs. SEQ ID NO: 11, SEQ ID NO: 12 or SEQ ID NO: 13. SEQ ID NOs: 8 to 13 correspond to the intergenic regions preceding, respectively, rplP, rpmD, rplM, rpsE, rplE, and rplF of Enterococcus faecium strain LMG15709

[0128] In an embodiment, the intergenic regions as described herein, excluding any preceding stop codon and excluding any subsequent start codon may comprise or consist of more than 1 nucleotide, such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 or more nucleotides, preferably more than 5 nucleotides, even more preferably 10 or more nucleotides. In another embodiment, the intergenic region may comprise 1 to 50 nucleotides, such as 1 to 40, 1 to 30, 1 to 25, 1 to 20, 1 to 15, or 1 to 10, preferably 5 to 50, 5 to 40, 5 to 30, 5 to 25, 5 to 20, 5 to 15, or 5 to 10 nucleotides, even more preferably 10 to 50, 10 to 40, 10 to 30, 10 to 25, 10 to 20, or 10 to 15 nucleotides.

[0129] Particularly preferred embodiments of gram-positive bacteria comprising a polycistronic expression unit as described herein are depicted in Tables 1 and 2, wherein said gram-positive bacterium comprises an endogenous promoter, 3' of which the endogenous gene coupled to the intergenic region as depicted in Tables 1 and 2, 3' of which one or more exogenous genes, open reading frame or coding sequence coupled to the intergenic region. In a preferred embodiment, each gene depicted in Tables 1 and 2 is transcriptionally controlled by its native promoter, and optionally regulatory sequences. In another preferred embodiment, said polycistronic expression unit is integrated in the bacterial chromosome. In a further preferred embodiment, said endogenous promoter and/or endogenous gene are present at their native locus on the bacterial genome or chromosome. Preferably, the start and stop codons, if present, replace the start and stop codons of said exogenous gene and said endogenous gene, respectively.
Table 1: Exemplary polycistronic expression unit may comprise or consist essentially of endogenous promoter » endogenous gene » intergenic region » exogenous gene, wherein the endogenous gene and intergenic region are selected from the combinations below.
endogenous geneintergenic region
eno rplW
eno rplP
eno rpmD
eno rplB
eno rpsG
eno rpsE
eno rplN
eno rplM
eno rplE
eno rplF
usp45 rplW
usp45 rplP
usp45 rpmD
usp45 rplB
usp45 rpsG
usp45 rpsE
usp45 rplN
usp45 rplM
usp45 rplE
usp45 rplF
gap rplW
gap rplP
gap rpmD
gap rplB
gap rpsG
gap rpsE
gap rplN
gap rplM
gap rplE
gap rplF
pyk rplW
pyk rplP
pyk rpmD
pyk rplB
pyk rpsG
pyk rpsE
pyk rplN
pyk rplM
pyk rplE
pyk rplF
rpmB rplW
rpmB rplP
rpmB rpmD
rpmB rplB
rpmB rpsG
rpmB rpsE
rpmB rplN
rpmB rplM
rpmB rplE
rpmB rplF
rplS rplW
rplS rplP
rplS rpmD
rplS rplB
rplS rpsG
rplS rpsE
rplS rplN
rplS rplM
rplS rplE
rplS rplF


[0130] Preferably, intergenic regions rplW, rplB, rpsG, and rplN originate from a Lactococcus species, subspecies or strain, preferably Lactococcus lactis. Preferably, intergenic regions rplP, rplM, and rplE originate from an Enterococcus species, subspecies or strain, preferably Enterococcus faecalis or Enterococcus Faecium. Preferably, intergenic regions rplP, rpmD, and rpsE originate from a Lactococcus species, subspecies or strain, preferably Lactococcus lactis or from an Enterococcus species, subspecies or strain, preferably Enterococcus faecalis or Enterococcus Faecium.

[0131] For example but without limitation, where the polycistronic expression unit comprises two exogenous genes, the structure represented as endogenous promoter >> endogenous gene >> intergenic region >> exogenous gene >> intergenic region >> exogenous gene may be as follows: usp45 >> usp45 >> rpmD >> exogenous gene 1 >> rplN >> exogenous gene 2; enoA >> enoA >> rpmD >> exogenous gene 1 >> rplN >> exogenous gene 2; gapB >> gapB >> rpmD >> exogenous gene 1 >> rplN >> exogenous gene 2. For example, such arrangement may be particularly suited for the expression of heavy and light chains of antibodies (preferably in that order), such as anti-TNFα antibodies as taught herein.
Table 2: Exemplary polycistronic expression unit may comprise or consist essentially of endogenous promoter » endogenous gene » intergenic region » exogenous gene, wherein the endogenous gene and intergenic region are selected from the combinations below.
endogenous geneintergenic region
eno SEQ ID NO: 1
eno SEQ ID NO: 2
eno SEQ ID NO: 3
eno SEQ ID NO: 4
eno SEQ ID NO: 5
eno SEQ ID NO: 6
eno SEQ ID NO: 7
eno SEQ ID NO: 8
eno SEQ ID NO: 9
eno SEQ ID NO: 10
eno SEQ ID NO: 11
eno SEQ ID NO: 12
eno SEQ ID NO: 13
usp45 SEQ ID NO: 1
usp45 SEQ ID NO: 2
usp45 SEQ ID NO: 3
usp45 SEQ ID NO: 4
usp45 SEQ ID NO: 5
usp45 SEQ ID NO: 6
usp45 SEQ ID NO: 7
usp45 SEQ ID NO: 8
usp45 SEQ ID NO: 9
usp45 SEQ ID NO: 10
usp45 SEQ ID NO: 11
usp45 SEQ ID NO: 12
usp45 SEQ ID NO: 13
gap SEQ ID NO: 1
gap SEQ ID NO: 2
gap SEQ ID NO: 3
gap SEQ ID NO: 4
gap SEQ ID NO: 5
gap SEQ ID NO: 6
gap SEQ ID NO: 7
gap SEQ ID NO: 8
gap SEQ ID NO: 9
gap SEQ ID NO: 10
gap SEQ ID NO: 11
gap SEQ ID NO: 12
gap SEQ ID NO: 13
pyk SEQ ID NO: 1
pyk SEQ ID NO: 2
pyk SEQ ID NO: 3
pyk SEQ ID NO: 4
pyk SEQ ID NO: 5
pyk SEQ ID NO: 6
pyk SEQ ID NO: 7
pyk SEQ ID NO: 8
pyk SEQ ID NO: 9
pyk SEQ ID NO: 10
pyk SEQ ID NO: 11
pyk SEQ ID NO: 12
pyk SEQ ID NO: 13
rpmB SEQ ID NO: 1
rpmB SEQ ID NO: 2
rpmB SEQ ID NO: 3
rpmB SEQ ID NO: 4
rpmB SEQ ID NO: 5
rpmB SEQ ID NO: 6
rpmB SEQ ID NO: 7
rpmB SEQ ID NO: 8
rpmB SEQ ID NO: 9
rpmB SEQ ID NO: 10
rpmB SEQ ID NO: 11
rpmB SEQ ID NO: 12
rpmB SEQ ID NO: 13
rplS SEQ ID NO: 1
rplS SEQ ID NO: 2
rplS SEQ ID NO: 3
rplS SEQ ID NO: 4
rplS SEQ ID NO: 5
rplS SEQ ID NO: 6
rplS SEQ ID NO: 7
rplS SEQ ID NO: 8
rplS SEQ ID NO: 9
rplS SEQ ID NO: 10
rplS SEQ ID NO: 11
rplS SEQ ID NO: 12
rplS SEQ ID NO: 13


[0132] Preferably, the gram-positive bacterium having a polycistronic expression unit comprising any of SEQ ID NOs: 1 to 7 is a Lactococcus species, subspecies or strain, preferably Lactococcus lactis. Preferably, the gram-positive bacterium having a polycistronic expression unit comprising any of SEQ ID NOs: 8 to 13 is an Enterococcus species, subspecies or strain, preferably Enterococcus faecalis or Enterococcus Faecium.

[0133] The skilled person will appreciate that the exogenous genes, open reading frames or coding sequences according to the invention can be coupled to additional sequences, which additional sequences effect a particular purpose. For instance, in order to increase secretion of the exogenous gene, the gene may be coupled to a nucleic acid sequence encoding a secretion signal peptide. In a particularly preferred embodiment, the exogenous gene, open reading frame or coding sequence according to the invention is coupled at its 5' end to the polynucleic acid sequence encoding the Usp45 secretion signal, preferably originating from a Lactococcus species, more preferably Lactococcus lactis and subspecies and strains thereof.

[0134] Typically, a secretion signal sequence represents an about 16 to about 35 amino acid segment, usually containing hydrophobic amino acids that become embedded in the lipid bilayer membrane, and thereby allow for the secretion of an accompanying protein or peptide sequence from the host cell, and which usually is cleaved from that protein or peptide. Preferably, the secretion signal sequence may be so-active in a host cell intended for use with the nucleic acid comprising the said signal sequence.

[0135] Secretion signal sequences active in suitable host cells are known in the art; exemplary Lactococcus signal sequences include those of usp45 (see, US 5,559,007) and others, see, e.g., Perez-Martinez et al. Mol. Gen. Genet., 1992, vol. 234, 401-11; Sibakov et al., Appl. Environ. Microbiol., 1991, vol. 57(2), 341-8. Preferably, the signal sequence is located between the promoter sequence and the ORF, i.e. the signal sequence is located 3' from the promoter sequence and precedes the ORF of the polypeptide of interest. In a preferred embodiment, the signal sequence encodes the amino acid sequence MKKKIISAILMSTVILSAAAPLSGVYA (usp45). Alternatively, a mutated usp45 signal sequence (usp45N) may be used which results in further controllable production and secretion of the polypeptide of interest. In particular, the mutant comprises an asparagine (N) at position 4 instead of a lysine (K), or a K4N mutation. In a preferred embodiment, the signal sequence encodes the amino acid sequence MKKNIISAILMSTVILSAAA PLSGVYADTN.

[0136] The invention also relates to a polynucleic acid sequence comprising a polycistronic expression unit according to the invention as described herein. In particular, in an aspect, the invention relates to a polynucleic acid sequence comprising a polycistronic expression unit according to the invention as described herein, wherein said polycistronic unit comprises one or more gene endogenous to a gram-positive bacterium and one or more gene, open reading frame or coding sequence exogenous to a gram-positive bacterium, wherein the one or more endogenous genes and the one or more exogenous genes are translationally or transcriptionally coupled in a way as described herein. Preferably the one or more endogenous genes is coupled to the 5' end of the one or more exogenous genes. Preferably, the one or more endogenous genes and the one or more exogenous genes are connected by an intergenic region as described herein, preferably an intergenic region preceding rplW, rplP, rpmD, rplB, rpsG, rpsE, and rplN as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 1 to 7 or an intergenic region preceding rplP, rpmD, rplM, rpsE, rplE, or rplF as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 8 to 13 or related sequences as described above. In an embodiment, the polynucleic acid sequence further comprises a promoter, preferably a promoter endogenous of a gram-positive bacterium. In another embodiment, the polynucleic acid sequence further comprises regulatory sequences, e.g. operator, terminator and the like. In a preferred embodiment, the promoter is the native promoter of the endogenous gene.

[0137] In a further aspect, the invention relates to a replicon comprising the polynucleic acid sequence as described herein. Preferably, said replicon is a vector, as described herein elsewhere. In an embodiment, said vector is suitable for prokaryotic expression. In another embodiment, said vector is suitable for homologous recombination in a gram-positive bacterium.

[0138] Described herein is a polynucleic acid sequence comprising a ribosome binding site of a gram positive bacterium and a gene, open reading frame or coding sequence exogenous to said bacterium, wherein the ribosome binding site is configured to effect translation of the exogenous gene, open reading frame or coding sequence. The polynucleic acid sequence may comprise a ribosome binding site of a gram positive bacterium and a gene, open reading frame or coding sequence exogenous to said bacterium, wherein the ribosome binding site is connected at the 5' end of the exogenous gene, open reading frame or coding sequence.

[0139] Described herein is a polynucleic acid sequence comprising an intergenic region, preferably an operon intergenic region, of a gram positive bacterium and a gene, open reading frame or coding sequence exogenous to said bacterium, wherein the intergenic region is configured to effect translation of the exogenous gene, open reading frame or coding sequence. The polynucleic acid sequence may comprise an intergenic region, preferably an operon intergenic region, of a gram positive bacterium and a gene, open reading frame or coding sequence exogenous to said bacterium, wherein the intergenic region is connected at the 5' end of the exogenous gene, open reading frame or coding sequence. Preferably, the intergenic region is an intergenic region preceding rplW, rplP, rpmD, rplB, rpsG, rpsE, or rplN as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 1 to 7 or an intergenic region preceding rplP, rpmD, rplM, rpsE, rplE, or rplF as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 8 to 13 or related sequences as described above.

[0140] Described herein is a polycistronic expression vector comprising the intergenic region preceding rplW, rplP, rpmD, rplB, rpsG, rpsE, or rplN as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 1 to 7 or an intergenic region preceding rplP, rpmD, rplM, rpsE, rplE, or rplF as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 8 to 13 or related sequences as described above. In an embodiment, said vector is suitable for cloning a gene, open reading frame or coding sequence at the 3' end of said intergenic region, preferably a gene which is exogenous to a gram-positive bacterium. In an embodiment, said vector is suitable for being replicated in a gram-positive bacterium. In a further embodiment, said vector is suitable for effecting homologous recombination in a gram-positive bacterium, in particular for chromosomal integration of said intergenic region and a gene, open reading frame or coding sequence at the 3' end of said intergenic region. In an embodiment, said vector further comprises one or more promoter, preferably a gram-positive bacterial promoter. In a further embodiment, said vector further comprises regulatory sequences, e.g. operator, terminator and the like. In yet another embodiment, said vector further comprises one or more selection markers, such as antibiotic resistance genes.

[0141] In another aspect, the invention relates to a method for exogenous gene expression in a gram-positive bacterium, comprising the step of transforming said gram-positive bacterium with the vector comprising an exogenous gene, open reading frame or coding sequence, optionally further comprising an endogenous promoter as described herein.

[0142] In a further aspect, the invention relates to the use of a polynucleic acid sequence comprising an intergenic region of a gram-positive bacterium as described herein for polycistronic expression of one or more genes, open reading frame or coding sequence exogenous to said gram-positive bacterium. In an embodiment, the invention relates to the use of a polynucleic acid sequence comprising an intergenic region of a gram-positive bacterium as described herein for polycistronic expression of one or more genes, open reading frames or coding sequences exogenous to said gram-positive bacterium and a gene, open reading frame or coding sequences endogenous to said gram-positive bacterium. In an embodiment, said one or more genes exogenous to said gram-positive bacterium is coupled to the 3' end of said endogenous gene. Preferably, the intergenic region is an intergenic region preceding rplW, rplP, rpmD, rplB, rpsG, rpsE or rplN as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 1 to 7 or an intergenic region preceding rplP, rpmD, rplM, rpsE, rplE, or rplF as described herein elsewhere or an intergenic region corresponding to any of SEQ ID NOs: 8 to 13 or related sequences as described above.

[0143] In another aspect, the invention relates to a method for expressing of one or more exogenous protein in a gram-positive bacterium, comprising the step of introducing a polynucleic acid sequence encoding said one or more exogenous protein or a vector as described herein in said gram-positive bacterium such as to be transcribed in a polycistronic mRNA.

[0144] In yet another aspect, the invention relates to a method for generating a gram-positive bacterium capable of expressing one or more exogenous proteins, comprising the step of introducing a polynucleic acid sequence encoding one or more exogenous protein or a vector as described herein in said gram-positive bacterium such as to be transcribed in a polycistronic mRNA.

[0145] According to the invention, the one or more exogenous genes, open reading frame of coding sequence can be of any kind or origin. In an embodiment, the one or more exogenous genes encodes a protein, polypeptide and/or peptide, preferably a protein, polypeptide and/or peptide having a therapeutic or preventive effect in a subject, or preferably an antigen such as an antigen for inducing immunity or immunotolerance, a non-vaccinogenic therapeutically active polypeptide, an antibody or a functional fragment thereof such as Fab, a fusion protein or a multimeric protein. In a preferred embodiment, the one or more exogenous genes encodes an antibody or a functional antibody fragment. As used herein, the term "functional" refers to an antibody fragment, which can still exert its intended function, i.e. antigen binding. The term antibody, as used here, includes, but is not limited to conventional antibodies, chimeric antibodies, dAb, bispecific antibody, trispecific antibody, multispecific antibody, bivalent antibody, trivalent antibody, multivalent antibody, VHH, nanobody, Fab, Fab', F(ab')2 scFv, Fv, dAb, Fd, diabody, triabody, single chain antibody, single domain antibody, single antibody variable domain.

[0146] In the present context, the term "antibody" is used to describe an immunoglobulin whether natural or partly or wholly engineered. As antibodies can be modified in a number of ways, the term "antibody" should be construed as covering any specific binding molecule or substance having a binding domain with the required binding specificity for the other member of the pair of molecules, i.e. the target molecule, as defined supra. Thus, this term covers antibody fragments, derivatives, functional equivalents and homologues of antibodies, as well as single chain antibodies, bifunctional antibodies, bivalent antibodies, VHH, nanobodies, Fab, Fab', F(ab')2, scFv, Fv, dAb, Fd, diabodies, triabodies and camelid antibodies, including any polypeptide comprising an immunoglobulin binding domain, whether natural or wholly or partially engineered. Chimeric molecules comprising an immunoglobulin binding domain, or equivalent, fused to another polypeptide are therefore included. The term also covers any polypeptide or protein having a binding domain which is, or is homologous to, an antibody binding domain, e.g. antibody mimics. Examples of antibodies are the immunoglobulin isotypes and their isotypic subclasses, including IgG (lgG1, IgG2a, IgG2b, IgG3, IgG4), IgA, IgD, IgM and IgE. The person in the art will thus appreciate that the present invention also relates to antibody fragments, comprising an antigen binding domain such as VHH, nanobodies Fab, scFv, Fv, dAb, Fd, diabodies and triabodies. In an embodiment, the invention relates to a gram-positive bacterium or a recombinant nucleic acid as described herein, wherein one exogenous gene encodes the light chain (VL) of an antibody or of a functional fragment thereof, and another exogenous gene encodes the heavy chain (VH) of the antibody or of a functional fragment thereof, more preferably wherein the functional fragment is Fab. In an embodiment, the exogenous gene encoding VL or functional fragment thereof is transcriptionally coupled to the 3' end of the exogenous gene encoding VH or functional fragment thereof.

[0147] In an embodiment, the antibody as described herein at least partially or fully blocks, inhibits, or neutralises a biological activity of a target molecule, such as a cytokine or chemokine. As used herein, the expression "neutralises" or "neutralisation" means the inhibition of or reduction in a biological activity of a cytokine as measured in vivo or in vitro, by methods known in the art, such as, for instance, as detailed in the examples. In particular, the inhibition or reduction may be measured by determining the colitic score or by determining the target molecule in a tissue or blood sample. As used herein, the expression "neutralises" or "neutralisation" means the inhibition of or reduction in a biological activity of a cytokine as measured in vivo or in vitro, by at least 10% or more, preferably by at least 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and even more preferably by 100%.

[0148] Preferably, said binding molecules are binding to and inhibiting the biological effect of cytokines chosen from the list of IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-12 (or its subunits IL-12p35 and IL12p40), IL-13, IL-15, IL-16, IL-17, IL-18, IL-21, IL-23 (or its subunit IL-23p19), IL-27, IL-32 (and its splice variants), IFN (α, β, γ) and TNFα. Preferably, said binding molecules are soluble cytokine receptors such as gp130, or are binding to the receptors of said cytokines, for example IL-2R (CD25, CD122, CD132), IL-12R (beta1, beta2), IL15R, IL-17R, IL-23R or IL-6R, without triggering an inflammatory signal. Preferably, said binding molecules are neutralizing chemokines chosen from the list of MIF, MIP-1α, MCP-1, RANTES and Eotaxin. Preferably, said binding molecules are solving the blockade of immune activation via binding to costimulatory molecules from the list of CD3/CD28, HVEM, B7.1/B7.2, CD40/CD40L(CD154), ICOS/ICOSL, OX40/X40L, CD27/CD27L(CD70), CD30/CD30L(CD153) and 41BB/41BBL. Preferably, said binding molecules are solving the blockade of inflammation via binding to adhesion molecules from the list I-CAM1, α4 integrin and α4β7 integrin. Preferably, said binding molecules have a costimulatory and agonistic effect on CD3, CTLA4 and/or PD1. Preferably, said binding molecules are neutralizing T-cells or B-cell activity by targeting CD25, CD20, CD52, CD95, BAFF, APRIL and/or IgE. Preferably, said binding molecules are solving the blockade of inflammation via binding to enzymes from the MMP family. Preferably, said binding molecules assert an anti-angiogenic effect, such as neutralizing αvβ3/α5β1 and IL-8 activity. In a further preferred embodiment said binding molecule is capable of neutralizing the biological effect of TNFα, .IL-12, IFNγ, IL-23 or IL-17. Preferably, said binding molecule is chosen from the group consisting of
  • an anti-TNFα antibody, anti-TNFα antibody fragment, anti-TNFα single antibody variable domain, soluble TNF receptor or dominant negative variant of TNFα;
  • anti-IL-12 antibody, anti-IL-12 antibody fragment, anti-IL-12 single antibody variable domain, soluble IL-12 receptor, dominant negative variant of IL-12 or IL-12 dAb;
  • anti-IL-12p35 antibody, anti-IL-12p35 antibody fragment, anti-IL-12p35 single antibody variable domain, soluble IL-12p35 receptor, dominant negative variant of IL-12p35 or IL-12p35 dAb;
  • anti-IL-12p40 antibody, anti-IL-12p40 antibody fragment, anti-IL-12p40 single antibody variable domain, soluble IL-12p40 receptor, dominant negative variant of IL-12p40 or IL-12p40 dAb;
  • anti-IL-23 antibody, anti-IL-23 antibody fragment, anti-IL-23 single antibody variable domain, soluble IL-23 receptor, dominant negative variant of IL-23 or IL-23 dAb;
  • anti-IL-23p19 antibody, anti-IL-23p19 antibody fragment, anti-IL-23p19 single antibody variable domain, soluble IL-23p19 receptor, dominant negative variant of IL-23p19 or IL-23p19 dAb;
  • an anti-IFNy antibody, anti-IFNy antibody fragment, anti-IFNy single antibody variable domain, soluble IFNγ receptor or dominant negative variant of IFNγ;
  • anti-IL-17 antibody, anti-IL-17 antibody fragment, anti-IL-17single antibody variable domain, soluble IL-17 receptor, dominant negative variant of IL-17 or IL-17 dAb; and
  • anti-MCP-1 antibody, anti-MCP-1 antibody fragment, anti-MCP-1single antibody variable domain, soluble IL-17 receptor, dominant negative variant of MCP-1 or MCP-1 dAb.


[0149] In a preferred embodiment, said antibody is a Fab fragment (fragment antigen-binding). Fab fragments are well known in the art. By means of further guidance, a Fab fragment is a region on an antibody that binds to antigens. It is composed of one constant and one variable domain of each of the heavy and the light chain.

[0150] In an embodiment, the Fab is cA2 anti-TNF Fab (of which the polynucleotide and polypeptide sequences of the variable domain of the heavy chain and the light chain are disclosed in US 6,790,444 as SEQ ID NO: 4 and 5 (heavy chain) and SEQ ID NO: 2 and 3 (light chain), respectively) or CDP870 anti-TNF Fab (of which the polynucleotide and polypeptide sequences of the heavy chain and the light chain are disclosed in WO 01/94585 as SEQ ID NO: 114 and 115 (heavy chain) and SEQ ID NO: 112 and 113 (light chain), respectively).

[0151] The skilled person will appreciate that antibodies, as are functional antibody fragments, and in particular Fab fragments, are composed of different individual polypeptides which may be covalently linked by disulphide bridges. In particular, the heavy chain and the light chain are encoded by separate individual coding sequences.

[0152] Accordingly, the coding regions of the heavy and light chains may each be comprised in a polycistronic expression unit as described herein. Polynucleic acid sequences encoding heavy and light chains may be incorporated in different polycistronic expression units. Preferably, polynucleic acid sequences encoding heavy and light chains are incorporated in the same polycistronic expression unit. Accordingly, in an embodiment, the invention relates to a gram-positive bacterium as described herein, comprising an endogenous gene, one or more polynucleic acid sequence encoding an antibody heavy chain, or a fragment, preferably a functional fragment thereof, and one or more polynucleic acid sequence encoding an antibody light chain, or a fragment, preferably a functional fragment thereof, which are translationally or transcriptionally coupled. In another embodiment, the invention relates to a gram-positive bacterium comprising a polycistronic expression unit, wherein said polycistronic expression unit comprises an endogenous gene, one or more polynucleic acid sequence encoding an antibody heavy chain, or a fragment, preferably a functional fragment thereof, and one or more polynucleic acid sequence encoding an antibody light chain, or a fragment, preferably a functional fragment thereof. In yet another embodiment, the polynucleic acid sequence encoding a light chain is transcriptionally or translationally coupled to 3' end of the polynucleic acid sequence encoding the heavy chain. Advantageously, such coupling further increases the expression of both heavy and light chain.

[0153] The invention also relates to the gram-positive bacteria according to the invention as described herein for use in therapy. The invention further relates to a pharmaceutical composition comprising the gram-positive bacterium according to the invention as described herein.

[0154] Accordingly, in an aspect, the invention relates to the gram-positive bacterium or a pharmaceutical composition comprising the gram-positive bacterium according to the invention as described herein for use as a medicament. In another aspect, the invention relates to the gram-positive bacterium or a pharmaceutical composition comprising the gram-positive bacterium according to the invention as described herein for use in therapy or treatment. In a further aspect, the invention relates to the use of the gram-positive bacterium or a pharmaceutical composition comprising the gram-positive bacterium according to the invention as described herein for the manufacture of a medicament. In yet another aspect, the invention relates to the gram-positive bacterium or a pharmaceutical composition comprising the gram-positive bacterium according to the invention as described herein for use in a method of treatment In an embodiment, the invention relates to a gram-positive bacterium or a pharmaceutical composition comprising a gram-positive bacterium as described herein, wherein the one or more exogenous genes encodes a product, such as a protein, polypeptide or peptide, which product has a therapeutic or preventive effect in a subject, preferably for use as a medicament, preferably for use in administration or delivery of said product to the subject.

[0155] In a related aspect, the invention provides a gram-positive bacterium according to the invetion for use in delivery of a polypeptide encoded by the one or more exogenous genes, open reading frame, or coding sequence to human or animal in need thereof, The animal may preferably be a mammal, such as, e.g., domestic animals, farm animals, zoo animals, sport animals, pet and experimental animals such as dogs, cats, guinea pigs, rabbits, rats, mice, horses, cattle, cows; primates such as apes, monkeys, orang-utans, and chimpanzees; canids such as dogs and wolves; felids such as cats, lions, and tigers; equids such as horses, donkeys, and zebras; food animals such as cows, pigs, and sheep; ungulates such as deer and giraffes; rodents such as mice, rats, hamsters and guinea pigs; and so on.

[0156] As used herein, the terms "treat" or "treatment" refer to both therapeutic treatment and prophylactic or preventative measures, wherein the object is to prevent or slow down (lessen) an undesired physiological change or disorder. A "human or animal in need of treatment" includes ones that would benefit from treatment of a given condition.

[0157] The term "therapeutically effective amount" refers to an amount of a therapeutic substance or composition effective to treat a disease or disorder in a subject, e.g., human or animal, i.e., to obtain a desired local or systemic effect and performance. By means of example, a therapeutically effective amount of bacteria may comprise at least 1 bacterium, or at least 10 bacteria, or at least 102 bacteria, or at least 103 bacteria, or at least 104 bacteria, or at least 105 bacteria, or at least 106 bacteria, or at least 107 bacteria, or at least 108 bacteria, or at least 109, or at least 1010, or at least 1011, or at least 1012, or at least 1013, or at least 1014, or at least 1015, or more gram-positive bacteria, e.g., in a single or repeated dose.

[0158] The gram-positive bacteria of the present invention may be administered alone or in combination with one or more active compounds. The latter can be administered before, after or simultaneously with the administration of the gram-positive bacteria.

[0159] A number of prior art disclosures on the delivery of antigens and/or therapeutically active polypeptides exist, and it shall be appreciated that such disclosures may be further advantageously modified with the gram-positive bacteria of the present invention. By means of example and not limitation, bacterial delivery of interleukins in particular IL-10 for treating colitis (e.g. WO 00/23471), IL-27 for modulating an inflammatory response (WO 2004/069177), delivery of antigens as vaccines (e.g. WO 97/14806), delivery of GLP-2 and related analogs may be used to treat short bowel disease, Crohn's disease, osteoporosis and as adjuvant therapy during cancer chemotherapy, etc. Furthermore, bacterial delivery of trefoil peptides may be used to treat diseases of the alimentary canal (e.g. WO 01/02570). In particular, the use of trefoil proteins or peptides for treatment of disorders of and damage to the alimentary canal, including the mouth, oesophagus, stomach, and large and small intestine, as well as for the protection and treatment of tissues that lie outside the alimentary canal are described in WO 97/38712 and WO 92/14837. These proteins can be used either to treat lesions in these areas or to inhibit the formation of lesions. These lesions can be caused by: radiation therapy or chemotherapy for the treatment of cancer, any other drug including alcohol which damages the alimentary canal, accidental exposure to radiation or to a caustic substance, infection, a digestive disorder including but not limited to oral mucositis, intestinal mucositis, esophagitis, proctitis, non-ulcer dyspepsia, gastritis, peptic or duodenal ulcer, gastric cancer, colon cancer, MALT lymphoma, Menetier's syndrome, gastro-oesophageal reflux disease, Crohn's disease, ulcerative colitis and acute colitis of chemical, bacterial or obscure origin. Trefoil peptides are particularly useful to treat acute colitis, oral mucositis, intestinal mucositis, esophagitis, proctitis. Further therapeutic applications are envisioned using the promoters and host cells of the invention.

[0160] Further non-limiting examples of the types of diseases treatable in humans or animals by delivery of therapeutic polypeptides according to the invention include, but are not limited to, e.g., inflammatory bowel diseases including Crohn's disease and ulcerative colitis (treatable with, e.g., IL-Ira, IL-10, IL-27 or trefoil peptides); autoimmune diseases, including but not limited to psoriasis, rheumatoid arthritis, lupus erythematosus (treatable with, e.g., IL-Ira , IL-27, IL-10 or the relevant auto-antigen); allergic diseases including but not limited to asthma, food allergies, (treatable with the relevant allergen); celiac disease (treatable with gluten allergens); neurological disorders including, but not limited to Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis (treatable with, e.g., brain devated neurotropic factor and ciliary neurotropic factor); cancer (treatable with, e.g., IL-1, colony stimulating factors or interferon- W); osteoporosis (treatable with, e.g., transforming growth factor f3); diabetes (treatable with, e.g., insulin); cardiovascular disease (treatable with, e.g., tissue plasminogen activator); atherosclerosis (treatable with, e.g., cytokines and cytokine antagonists); hemophilia (treatable with, e.g., clotting factors); degenerative liver disease (treatable with, e.g., hepatocyte growth factor or interferon a); pulmonary diseases such as cystic fibrosis (treatable with, e.g., alpha antitrypsin); obesity; pathogen infections, e.g., viral or bacterial infections (treatable with any number of the above-mentioned compositions or antigens); etc.

[0161] The gram-positive bacteria according to the invention can also be used to treat infectious diseases. In an embodiment, passive immunization against Clostridium associated disease, preferably Clostridium dificile associated disease (CDAD), with toxin-neutralizing antibodies locally produced and secreted via the gram-positive bacterium according to the invention can be obtained. Preferably, said gram positive bacterium is a Lactococcus sp., more preferably Lactococcus lactis or a subspecies or a strain thereof.

[0162] CDAD is mediated by two exotoxins, toxin A (enterotoxin; see for instance Genbank NC_009089.1, region: 795843..803975 for DNA sequence or YP_001087137.1 for protein sequence) and toxin B (cytotoxin; see for instance Genbank NC_009089.1, region: 787393..794493 for DNA sequence or YP_001087135.1 for protein sequence). Both are high-molecular-mass proteins that bind to the surface of intestinal epithelial cells, where they are internalized and catalyze the glucosylation of cytoplasmic rho proteins, leading to cell death, inflammation and diarrhea. They have also been implicated in promoting C. difficile virulence, colonization, and neutrophil chemotaxis and activation. The bacteria itself is not invasive and does not cause tissue damage. By neutralizing the C. difficile toxins with antibodies, the pathogenic mechanism of the pathogen is blocked, its ability to thrive in the gut may be diminished, and the impact on the microbial ecology could be minimized, allowing recovery of the normal microflora. The medical advantage of this approach could include more rapid recovery, fewer relapses, and relief from selective pressure for antibiotic resistance in normal gut flora.

[0163] Accordingly, in an embodiment, the invention relates to a gram-positive bacterium as described herein, in which the polycistronic expression unit comprises an antibody or fragment thereof, preferably a Fab, as described herein elsewhere, directed against toxin A and/or toxin B of Clostridium. Most preferably, said antibody or fragment thereof is a neutralizing antibody. In a further embodiment, the invention relates to a gram-positive bacterium, preferably a Lactococcus sp. such as Lactococcus lactis or an Enterococcus sp. such as Enterococcus faecalis or Enterococcus faecium, comprising a polycistronic expression unit, preferably integrated in the bacterial chromosome, said polycistronic expression unit comprising an endogenous gene, preferably selected from the group consisting of eno, usp45, gap, pyk, rpmB and rplS, preferably originating from a Lactococcus sp. or an Enterococcus sp., and one or more exogenous genes encoding a neutralizing antibody or antibody fragment, preferably a Fab, against toxin A and/or toxin B of Clostridium, preferably Clostridium dificile, said polycistronic expression unit being preferably chromosomally integrated at the native locus of said endogenous gene, and said toxin A and/or toxin B antibody (fragment) gene preferably being transcriptionally coupled to the 3' end of said endogenous gene, said transcriptional coupling preferably being effected by an intergenic region, preferably selected from the group consisting of intergenic regions preceding rplW, rplP, rpmD, rplB, rpsG, rpsE, rplN, rplM, rplE, and rplF of a gram-positive bacterium, preferably a Lactococcus sp. or a Enterococcus sp. The Clostridium toxin A and toxin B antibodies as described herein are known in the art (see e.g. Leung et al., J Pediatr 1991;118(4 Pt 1):633-637; Wilcox. J Antimicrob Chemother 2004;53(5):882-884; Sougioultzis et al., Gastroenterology 2005;128(3):764-770; Kyne et al., N Engl J Med 2000;342(6):390-397; Lowy et al., N Engl J Med;362(3):197-205). Both antibodies or fragments thereof may be located on separate polycistronic expression units in the same or different gram-positive bacterium, but preferably are located on a single polycistronic expression unit. The invention further relates to a method for preventing and/or treating CDAD, comprising administering such gram-positive bacterium.

[0164] The skilled reader shall appreciate that the herein specifically recited diseases are only exemplary and their recitation is in no way intended to confine the use of the reagents provided by the invention, e.g., the promoters, nucleic acids, vectors and host cells of the invention, to these particular diseases. Instead, a skilled reader understands that the reagents of the invention can be used to express in principle any expression products, preferably polypeptides, of interest, which may be of therapeutic relevance in not only the recited ones but also in various further diseases or conditions of humans and animals. Consequently, once a suitable expression product, preferably a polypeptide, e.g., an antigen, antibody (fragment) and/or a non-vaccinogenic therapeutically active polypeptide, has been chosen or determined for a given ailment, a skilled person would be able to achieve its expression, isolation and/or delivery using the reagents of the invention.

[0165] The invention also contemplates treatment of diseases in other animals including dogs, horses, cats and birds. Diseases in dogs include but are not limited to canine distemper (paramyxovirus), canine hepatitis (adenovirus Cav-1), kennel cough or laryngotracheitis (adenovirus Cav-2), infectious canine enteritis (coronavirus) and haemorrhagic enteritis (parvovirus).

[0166] Diseases in cats include but are not limited to viral rhinotracheitis (herpesvirus), feline caliciviral disease (calicivirus), feline infectious peritonitis (parvovirus) and feline leukaemia (feline leukaemia virus). Other viral diseases in horses and birds are also contemplated as being treatable using the methods and compositions of the invention. To this purpose, the use of microorganisms expressing recombinant interferons will be particularly preferred.

[0167] As used herein, the pharmaceutical composition preferably comprises a therapeutically effective amount of the gram-positive bacteria of the invention and a pharmaceutically acceptable carrier, i.e., one or more pharmaceutically acceptable carrier substances and/or additives, e.g., buffers, carriers, excipients, stabilisers, etc.

[0168] The term "pharmaceutically acceptable" as used herein is consistent with the art and means compatible with the other ingredients of a pharmaceutical composition and not deleterious to the recipient thereof.

[0169] The gram-positive bacteria of the invention can be suspended in a pharmaceutical formulation for administration to the human or animal having the disease to be treated. Such pharmaceutical formulations include but are not limited to live gram-positive bacteria and a medium suitable for administration. The gram-positive bacteria may be lyophilized in the presence of common excipients such as lactose, other sugars, alkaline and/or alkali earth stearate, carbonate and/or sulphate (for example, magnesium stearate, sodium carbonate and sodium sulphate), kaolin, silica, flavorants and aromas. Gram-positive bacteria so-lyophilized may be prepared in the form of capsules, tablets, granulates and powders (e.g. a mouth rinse powder), each of which may be administered by the oral route. Alternatively, some gram-positive bacteria may be prepared as aqueous suspensions in suitable media, or lyophilized bacteria may be suspended in a suitable medium just prior to use, such medium including the excipients referred to herein and other excipients such as glucose, glycine and sodium saccharinate.

[0170] For oral administration, gastroresistant oral dosage forms may be formulated, which dosage forms may also include compounds providing controlled release of the gram-positive bacteria and thereby provide controlled release of the desired protein encoded therein. For example, the oral dosage form (including capsules, tablets, pellets, granulates, powders) may be coated with a thin layer of excipient (usually polymers, cellulosic derivatives and/or lipophilic materials) that resists dissolution or disruption in the stomach, but not in the intestine, thereby allowing transit through the stomach in favour of disintegration, dissolution and absorption in the intestine.

[0171] The oral dosage form may be designed to allow slow release of the gram-positive bacteria and of the produced exogenous proteins, for instance as controlled release, sustained release, prolonged release, sustained action tablets or capsules. These dosage forms usually contain conventional and well known excipients, such as lipophilic, polymeric, cellulosic, insoluble, swellable excipients. Controlled release formulations may also be used for any other delivery sites including intestinal, colon, bioadhesion or sublingual delivery (i.e., dental mucosal delivery) and bronchial delivery. When the compositions of the invention are to be administered rectally or vaginally, pharmaceutical formulations may include ointments, suppositories and creams. In this instance, the gram-positive bacteria are suspended in a mixture of common excipients also including lipids. Each of the aforementioned formulations are well known in the art and are described, for example, in the following references: Hansel et al., Pharmaceutical dosage forms and drug delivery systems, 5th edition, William and Wilkins, 1990; Chien 1992, Novel drug delivery system, 2nd edition, M. Dekker; Prescott et al. (1989, Novel drug delivery, J.Wiley & Sons); Cazzaniga et al, (1994, Oral delayed release system for colonic specific delivery, Int. J. Pharm.i08:7'.

[0172] Preferably, an enema formulation may be used for rectal administration. The term "enema" is used to cover liquid preparations intended for rectal use. The enema may be usually supplied in single-dose containers and contains one or more active substances dissolved or dispersed in water, glycerol or macrogols or other suitable solvents.

[0173] Thus, according the invention, in a preferred embodiment, the gram-positive bacteria according to the invention as described herein encoding a desired exogenous gene may be administered to the animal or human via mucosal, e.g., an oral, nasal, rectal, vaginal or bronchial route by any one of the state-of-the art formulations applicable to the specific route. Dosages of gram-positive bacteria for administration will vary depending upon any number of factors including the type of bacteria and the gene encoded thereby, the type and severity of the disease to be treated and the route of administration to be used.

[0174] Thus, precise dosages cannot be defined for each and every embodiment of the invention, but will be readily apparent to those skilled in the art once armed with the present invention. The dosage could be anyhow determined on a case by case way by measuring the serum level concentrations of the recombinant protein after administration of predetermined numbers of cells, using well known methods, such as those known as ELISA or Biacore (see examples). The analysis of the kinetic profile and half life of the delivered recombinant protein provides sufficient information to allow the determination of an effective dosage range for the transformed host cells.

[0175] In an embodiment, when the gram-positive bacteria according to the invention as described herein express an antigen, the invention may thus also provide a vaccine.

[0176] The term "vaccine" identifies a pharmaceutically acceptable composition that, when administered in an effective amount to an animal or human subject, is capable of inducing antibodies to an immunogen comprised in the vaccine and/or elicits protective immunity in the subject.

[0177] The vaccine of the invention would comprise the gram-positive bacteria according to the invention as described herein and further optionally an excipient. Such vaccines may also comprise an adjuvant, i.e., a compound or composition that enhances the immune response to an antigen. Adjuvants include, but are not limited to, complete Freund's adjuvant, incomplete Freund's adjuvant, saponin, mineral gels such as aluminum hydroxide, surface active substances such as lysolecithin, pluronic polyols, polyanions, peptides, oil or hydrocarbon emulsions, and potentially useful pharmaceutically acceptable human adjuvants such as BCG (bacille Calmetle-Guerin) and Corynebacterium parvum.

[0178] Described herein are biomarkers, uses and methods that provide for substantial advantages in the diagnosis, prediction, prognosis and/or monitoring of impaired fracture healing.

[0179] The aspects and embodiments of the invention are further supported by the following non-limiting examples.

Examples


Example 1: Selection of intergenic regions from the Lactococcus lactis genome



[0180] Cellular proteins of an end-log culture of Lactococcus lactis ssp. cremoris strain MG1363 were visualized onto a protein gel with Coomassie blue staining, as indicated in Figure 1. Lanes A and B contained 29 µg and 58 µg MG1363 proteins, respectively. 12 defined proteins bands from lane A were isolated from the gel. Proteins were isolated and intergenic regions were identified by:
  1. 1) Identification of abundantly expressed proteins in the fragments by partial peptide sequencing (MALDI-TOF/TOF) and database search using combined peptide masses and sequence information
  2. 2) Identification, using the chromosome sequence of Lactococcus lactis ssp. cremoris strain MG1363 (Wegmann et al), of genes encoding the abundantly expressed proteins (1) that are present in an operon, but not as a "first gene"
  3. 3) Identification of intergenic regions that precede these abundantly expressed genes


[0181] Table 3 lists thus identified intergenic regions. Underlined sequences represent ribosome binding sites.
Table 3
Intergenic region2nd geneFunction 2nd gene
TAATG (SEQ ID NO: 1) rplW 50 S ribosomal protein L23
TAATCCATG (SEQ ID NO: 2) rplP 50 S ribosomal protein L16
TAAGGAGGAAAAAATG (SEQ ID NO: 3) rpmD 50 S ribosomal protein L30
TAATAGAGGAGGAAAATCGTG (SEQ ID NO: 4) rplB 50 S ribosomal protein L2
TAAGAAGGGAGATAAGTAAGAATG (SEQ ID NO: 5) rpsG 30 S ribosomal protein S7
TAAGGAAAGGGGTAATTAAACATG (SEQ ID NO: 6) rpsE 30 S ribosomal protein S5
TAAGCAAAACTAGGAGGAATATAGCATG (SEQ ID NO: 7) rplN 50 S ribosomal protein L14

Example 2: Selection of sites for bicistronic expression



[0182] Table 4 lists target promoters identified in Example 1 as driving high level expression. These promoters can be used as target sites for polycistronic expression of exogenous genes.
Table 4
BandGene as annotated in MG1363Name
     
1 DNA-directed RNA polymerase, beta' subunit / 160 kD subunit rpoC
DNA-directed RNA polymerase, beta subunit / 140 kD subunit rpoB
non-heme iron-binding ferritin dpsA
2 pyruvate kinase pyk
glutamyl -tRNA synthetases gltX
3 phosphopyruvate hydratase eno
glutamine synthetase glnA
glutamine synthetase repressor glnR
dipeptidase PepV pepV
F0F1-type ATP synthase beta subunit (ATP synthase F1 beta subunit) atpD
F0F1-type ATP synthase alpha subunit atpA
4 multiple sugar-binding transport ATP-binding protein msmK
acetoin dehydrogenase complex E1 component alpha subunit (acoA) pdhA
cell division protein ftsA
UDP-galactopyranose mutase glf1
3-phosphoglycerate kinase pgk
glyceraldehyde-3-phosphate dehydrogenase gapB
acetate kinase ackA1
3-oxoacyl-(acyl-carrier-protein) synthase II fabF
5 3-ketoacyl-(acyl-carrier-protein) reductase fabG
DNA-directed RNA polymerase, alpha subunit / 40 kD subunit rpoA
Proline dipeptidase pepQ
glutamyl aminopeptidase pepA
predicted dehydrogenase related protein IImg_0272
6 30S ribosomal protein S2 rpsB
50S ribosomal protein L4 (rplD) rplD
50S ribosomal protein L23 rplW
50S ribosomal protein L2 rplB
Phenylalanyl-tRNA synthetase beta chain pheT
fructose-bisphosphate aldolase fbaA
7 30S ribosomal protein S4 rpsD
translation initiation factor 3 (IF-3) infC
transcription elongation factor GreA greA
protease subunit of ATP-dependent Clp protease clpP
superoxide dismutase sodA
8 30S ribosomal protein S12 rpsL
30S ribosomal protein S7 rpsG
50S ribosomal protein L18 rplR
30S ribosomal protein S5 rpsE
50S ribosomal protein L30/L7E rpmD
S-ribosylhomocysteinase luxS
50S ribosomal protein L15 rplO
50S ribosomal protein L11 rplK
9 30S ribosomal protein S8 rpsH
50S ribosomal protein L21 rplU
30S ribosomal protein S13 rpsM
30S ribosomal protein S19 (rpsS) rpsS
ribosomal protein L22 (rplV) rplV
ribosomal protein L16 (rplP) rplP
ribosomal protein L14 (rplN) rplN
30S ribosomal protein L19 rplS
  30S ribosomal protein S11 rpsK
10 30S ribosomal protein S10 rpsJ
co-chaperonin GroES groES
50S ribosomal protein L24 rplX
50S ribosomal protein L10 rplJ
50S ribosomal protein L7/L12 rplL
11 HU-like DNA-binding protein hllA
50S ribosomal protein L28 rpmB
phosphotransferase system IIB component ptcB


[0183] The β-giucuronidase (uidA) gene from E. coli was introduced as reporter gene in Lactococcus lactis MG1363. The uidA gene product β-glucuronidase, catalyses the cleavage of a wide variety of β-glucuronides that are commercially available as histochemical and spectrophotometric substrates. Strain sAGX0090 has the PhIIA>>uidA expression cassette at the thyA locus (Figure 2). This promoter was also used in strains sAGX0037 and sAGX0085.

[0184] As depicted in Figure 2, dual cistron constructs were made by inserting uidA in the Lactococcus lactis MG1363 chromosome at the 3' end of several endogenous genes (gene X). Hereby, rpmD was used as intergenic sequence between the endogenous genes of interest from Table 4 and uidA to identify sites that result in higher β-glucuronidase (GUS) activity compared to sAGX0090.

[0185] Lactococcus lactis cultures were grown for 16 hours at 30°C in GM17 supplemented with thymidine when needed. Cells of 1 ml culture were washed and resuspended in 1 ml demineralized water. Cells were disrupted with MP Biomedicals lysing matrix B and Fasprep-24 device at 6 m/s for 40 seconds. Tubes were centrifuged and a dilution series of the cell supernatant was made. GUS activity was measured by adding p-nitrophenyl substrate and β-mercaptoethanol which gives the solution a yellow colour upon presence of β-glucuronidase. GUS activity was measured at 405 nm and expressed relatively to reference strain sAGX0090. All strains were treated in parallel.

[0186] Figure 3 shows relative GUS-activity of gene X>>rpmD>>uidA dual cistron constructs. GUS-activity is expressed relatively to reference strain sAGX0090 that carries the PhIIA>>uidA expression cassette and is indicated on the Y-axis. GUS-activity in all dual cistron strains was found to be higher than the reference strain. In particular, GUS-activity in sAGX0168 (enoA>>rpmD>>uidA) and sAGX0222 (gapB>>rpmD>>uidA) was found to be 6.89 and 20.99 times higher when compared to sAGX0090, respectively.

[0187] These results clearly confirm that bicistronic expression allows enhanced protein expression levels over a wide variety of settings.

Example 3: Bicistronic expression of human pro-insulin



[0188] The usp45 secretion leader (SS) was fused to human pro-insulin (ins) to obtain secretion of pro-insulin (SS::ins). The [SS::ins] expression cassette was either integrated in the Lactococcus lactis MG1363 chromosome at the thyA locus and expressed directly from PthyA (sAGX0121) or was inserted, along with the rpmD intergenic region preceding SS::ins, as a second cistron downstream from usp45 (sAGX0121) or enoA (sAGX0164) (Figure 4a). The insulin secretion capacity was quantified by ELISA to evaluate bicistronic expression of cargo compared to PthyA driven expression at the thyA locus.

[0189] Attempts to construct a PhIIA>>SS::Ins integration plasmid have failed.

[0190] Strains were inoculated from single colony into 2 ml GM17 supplemented with 200 µM thymidine when needed and grown for 16 hours at 30°C. For the quantification of pro-insulin secretion, these saturated overnight cultures were diluted 1/25 in 5 ml fresh GM17 medium and grown for 4 hours at 30°C. Cells were collected by centrifugation at 3220 x g for 10 minutes, resuspended in an equal amount BAM9 medium and cultured for another 3 hours at 30°C. BAM9 contains M9 salts, 0.5% aminoplasmal, 0.5% glucose, 25 mM NaHCO3, 25 mM Na2CO3, 2 mM MgSO4, 0.1 mM CaCl2 and 200 µM thymidine. Cells and culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. The amount of secreted human pro-insulin in the culture supernatant was quantified by ELISA provided by Mercodia. All strains were treated in parallel.

[0191] Figure 4b represents the quantification of human pro-insulin secretion by Lactococcus lactis strains sAGX0122, sAGX0121 and.sAGX0164, The amount of secreted pro-insulin was expressed as ng/ml and indicated on the Y-axis. The figure clearly demonstrates that strains comprising a bicistronic expression cassette have a significantly higher cargo expression than reference strain. In particular, insulin secretion was highest when SS::ins was coupled through rpmD to enoA.

Example 4: Bicistronic expression of cA2 Fab



[0192] Dual cistron expression constructs were generated with heavy chain and light chain of cA2 anti-hTNF Fab. All expression units are driven by the thyA promoter and are located on plasmids. All carry genes for the light chain, VLCL (L) and the Fab fragment of the heavy chain, VHCH1 (H), derived from the cA2 infliximab monoclonal antibody. L>>H and H>>L configurations are coupled by intergenic regions preceding rpmD, rplB, rpsG, rpsE or rplN. All constructs are plasmid borne.

[0193] Figure 5 reveals that both heavy chain and light chains were highly expressed by the dual cistron constructs, leading to high levels of functional cA2 anti-TNF Fab. Figure 5 further reveals that cA2 anti-TNF expression increased when the heavy chain was positioned before the light chain, irrespective of the intergenic region.

[0194] For the quantification of anti-hTNF secretion, strains were inoculated from single colony into 2 ml GM17 and grown for 16 hours at 30°C. These saturated overnight cultures were diluted 1/25 in 5 ml fresh GM17 medium and grown for 4 hours at 30°C. Cells were collected by centrifugation at 3220 x g for 10 minutes, resuspended in an equal amount BAM9 medium and cultured for another 3 hours at 30°C. BAM9 contains M9 salts, 0.5% aminoplasmal, 0.5% glucose, 25 mM NaHCO3, 25 mM Na2CO3, 2 mM MgSO4, 0.1 mM CaCl2 and 200 µM thymidine. Cells and culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. Crude supernatants from strains carrying the individual constructs were prepared in parallel and were assayed for the presence of anti-TNF activity. This was done by direct ELISA using human TNF as capture protein. VLCL portions were detected by rabbit anti-human IgG antiserum and revealed by alkaline phosphatase conjugated anti-rabbit antiserum. Phosphatase activity was measured by colorimetric assay and read out as OD402. All strains were treated in parallel.

Example 5: Bicistronic expression of CDP870



[0195] Dual cistron expression constructs were generated with heavy chain and light chain of CDP870 anti-TNF Fab. All expression units are located on the bacterial chromosome.

[0196] Figure 6a: CDP870 light and heavy chain Fab fusions to usp45 secretion leader encoding sequences (SS::CDP870 VLCL and SS::CDP870 VHCH1) were inserted as a second and third cistron downstream from usp45 (sAGX0219, sAGX0220). In sAGX0219 and sAGX0220, rpmD was used to couple SS::CD870 genes to usp45. To avoid genetic instability, light and heavy chain genes were coupled through the intergenic region preceding rplN. In sAGX0219, the light chain gene precedes the heavy chain gene, while in sAGX0220, the heavy chain gene precedes the light chain gene.

[0197] For the quantification of anti-hTNF secretion, strains were inoculated from single colony into 2 ml GM17 and grown for 16 hours at 30°C. These saturated overnight cultures were diluted 1/25 in 5 ml fresh GM17 medium and grown for 4 hours at 30°C. Cells were collected by centrifugation at 3220 x g for 10 minutes, resuspended in an equal amount BAM9 medium and cultured for another 3 hours at 30°C. BAM9 contains M9 salts, 0.5% aminoplasmal, 0.5% glucose, 25 mM NaHCO3, 25 mM Na2CO3, 2 mM MgSO4, 0.1 mM CaCl2 and 200 µM thymidine. Cells and culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. Crude supernatants from strains carrying the individual constructs were prepared in parallel and were assayed for the presence of anti-TNF activity. This was done by direct ELISA using human TNF as capture protein with Remicade as a reference standard. VLCL portions were detected by rabbit anti-human IgG antiserum and revealed by alkaline phosphatase conjugated anti-rabbit antiserum. Phosphatase activity was measured by colorimetric assay and read out as OD402. All strains were treated in parallel.

[0198] Figure 6b reveals that both heavy chain and light chains were highly expressed by the dual cistron constructs, leading to high levels of functional CDP870 anti-TNF Fab. Figure 6b further reveals that CDP870 anti-TNF expression substantially increased when the heavy chain was positioned before the light chain.

Example 6: Bicistronic expression of human trefoil factor 1 (hTFF1)



[0199] Expression constructs were generated with the usp45 secretion leader coding sequence fused to hTFF1 (SS::hTFF1). All expression units are located on the bacterial chromosome. It was not possible to construct integration plasmids for monocistronic hTFF1 expression using stronger promoters than PhllA.

[0200] Figure 7a: The usp45 secretion leader coding sequence (SS) was fused to hTFF1 to obtain secretion of hTFF1 (SS::hTFF1). The SS::hTFF1 expression cassette was either integrated in the Lactococcus lactis MG1363 chromosome at the thyA locus and expressed directly from PhllA (sAGX0085) or was inserted, along with the rpmD intergenic region preceding SS::hTFF1, as a second cistron downstream from gapB (sAGX0276).

[0201] Figure 7b: The hTFF1 secretion capacity was quantified by ELISA to evaluate bicistronic expression of cargo compared to PhllA driven expression at the thyA locus.

[0202] For the quantification of hTFF1 secretion, strains were inoculated from single colony into 2 ml GM17 and grown for 16 hours at 30°C. These saturated overnight cultures were diluted 1/25 in 5 ml fresh GM17 medium and grown for 4 hours at 30°C. Cells were collected by centrifugation at 3220 x g for 10 minutes, resuspended in an equal amount BAM9 medium and cultured for another 3 hours at 30°C. BAM9 contains M9 salts, 0.5% aminoplasmal, 0.5% glucose, 25 mM NaHCO3, 25 mM Na2CO3, 2 mM MgSO4, 0.1 mM CaCl2 and 200 µM thymidine. At this stage, colony forming units (CFU) of all cultures were determined. Cells and culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. Crude supernatants from strains carrying the individual constructs were prepared in parallel and were assayed by ELISA using purified hTFF1 as a reference standard. The amount of secreted hTFF1 was expressed as ng/ml and ng/109 CFU. All strains were treated in parallel.

[0203] Figure 7b clearly demonstrates that the strain comprising a bicistronic expression cassette (sAGX0276) has a significantly higher cargo expression than reference strain (sAGX0085). The amount of secreted hTFF1 expression was substantially enhanced (>5 fold per ml; >12 fold per CFU) when hTFF1 was coupled through rpmD to gapB.

Example 7: Selection of intergenic regions from the Enterococcus faecium genome



[0204] Cellular proteins of an end-log culture of Enterococcus faecium strain LMG 15709 (Enterococcus faecium [Orla-Jensen 1919] Schleifer and Kilpper-Bälz 1984 VP; LMG 15709; ATCC 6057; DSM 2146; NCIMB 8842) were visualized onto a protein gel with Coomassie blue staining, as indicated in Figure 8. Lanes A, B and C contained the cellular proteins of the lysed cell equivalent of 284 µl, 142 µl and 56.8 µl end-log culture of Entercococcus faecium LMG15709, respectively. 12 defined proteins bands from lane C were isolated from the gel. Proteins were isolated and intergenic regions were identified by:
  1. 1) Identification of abundantly expressed proteins in the fragments by partial peptide sequencing (MALDI-TOF/TOF) and database search using combined peptide masses and sequence information.
  2. 2) Identification, using the chromosome sequence of Enterococcus faecium PC4.1 (retrieved form the NCBI Genome databank, GenBank accession number ADMM01000000), of genes encoding the abundantly expressed proteins (1) that are present in an operon, but not as a "first gene".
  3. 3) Identification of intergenic regions that precede these abundantly expressed genes (Table 5).


[0205] Table 5 lists identified intergenic regions in Enterococcus faecium LMG15709. Underlined sequences represent ribosome binding sites.
Table 5
Intergenic region2nd geneFunction 2nd gene
TAATC (SEQ ID NO: 8) rplP 50S ribosomal protein L16
TAAGGAGGACAACAATA (SEQ ID NO: 9) rpmD 50S ribosomal protein L30
TAATAGGAGGGAATTTCA (SEQ ID NO: 10) rplM 50S ribosomal protein L13
TTAGAAGAAGGAGGAATACCATTC (SEQ ID NO: 11) rpsE 30S ribosomal protein S5
TAAAAGTTTAAGGAAGGAGGGTCTTACTGA (SEQ ID NO: 12) rplE 50S ribosomal protein L5
TAATCAAGTAGAATCTACAAGGAGGTGTCTTTAA (SEQ ID NO: 13) rplF 50S ribosomal protein L6

Example 8: Selection of sites in the Enterococcus faecium genome for bicistronic expression



[0206] Table 6 lists highly expressed Enterococcus faecium genes identified in Example 7 as driving high level expression. Promoters driving these genes can be used as target sites for polycistronic expression of exogenous genes. These endogenous genes can further be used as first gene in a polycistronic expression module, transcriptionally or translationally coupled, through an intergenic region, to downstream exogenous genes.
Table 6
BandGene annotationName
1 Enolase [Enterococcus faecium DO]; gi|69249235 eno
Elongation factor Tu [Enterococcus faecium TX13330]; gi|227550718 tuf
2 Glyceraldehyde-3-phosphate dehydrogenase [Enterococcus faecium TX1330]; gi|227552066 gap
3 L-lactate dehydrogenase [Enterococcus faecium DO]; gi|69245441 ldh
Aspartate carbamoyltransferase [Enterococcus faecium DO]; gi|69247601 pyrB
Ribose-phosphate pyrophosphokinase [Enterococcus faecium DO]; gi|69245416  
4 Pyruvate kinase [Enterococcus faecium DO]; gi|69247355 Oligoendopeptidase F [Enterococcus faecium E1039]; gi|293553061 Aspartyl-tRNA synthetase bacterial/mitochondrial type [Enterococcus faecium DO]; gi|69247937 pyk pepF aspS
5 Lysyl-tRNA synthetase [Enterococcus faecium TX1330]; gi|227552660 lysS
  GroEL [Enterococcus faecium]; gi|35187728 groEL
6 Phosphoglycerate kinase [Enterococcus faecium E1039]; gi|293557157 pgk
7 Fructose-bisphosphate aldolase class-II [Enterococcus faecium 1,230,933]; gi|293557157  
2,3-bisphosphoglycerate-dependent phosphoglycerate mutase [Enterococcus faecium E1039]; gi|293556592  
Saicar synthetase [Enterococcus faecium 1,141,733]; gi|257887626 purC
8 2,3-bisphosphoglycerate-dependent phosphoglycerate mutase [Enterococcus faecium E1039]; gi|293556592  
Saicar synthetase [Enterococcus faecium 1,231,501]; gi|257884790 purC
9 50S ribosomal protein L5 [Enterococcus faecium DO]; gi|69247181 rplE
50S ribosomal protein L6 [Enterococcus faecium DO]; gi|69247184 rplF
Peroxiredoxin [Enterococcus faecium TX1330]; gi|227551517 aphC
Xanthine phosphoribosyltransferase [Enterococcus faecium 1,230,933]; gi|257878081  
10 Elongation factor G [Enterococcus faecium TX1330]; gi|227550717 fusA
11 30S ribosomal protein S5, bacterial and organelle form [Enterococcus faecium DO]; gi|69247186 rpsE
50S ribosomal protein L16 [Enterococcus faecium]; gi|9931590 rplP
Universal stress protein family [Enterococcus faecium E980]; gi|293571359  
Ferritin [Enterococcus faecium 1,230,933]]; gi|257880413  
30S ribosomal protein S7 [Enterococcus faecium TX1330]; gi|227550716 rpsG
50S ribosomal protein L13 [Enterococcus faecium 1,230,933]; gi|257880414 rplM
12 M20 family peptidase PepV [Enterococcus faecium TX1330]; gi|227550917 pepV
Glutamyl-tRNA synthetase bacterial/mitochondrial [Enterococcus faecium DO]; gi|69245495 gltX
Cell division protein FtsA [Enterococcus faecium DO]; gi|69244711 ftsA
Asparaginyl-tRNA synthetase, class IIb [Enterococcus faecium DO]; gi|69247321 asnC


[0207] In such way, the β-giucuronidase (uidA) gene from E. coli was introduced as reporter gene in Enterococcus faecium LMG15709. The uidA gene product β-glucuronidase, catalyses the cleavage of a wide variety of β-glucuronides that are commercially available as histochemical and spectrophotometric substrates. As depicted in Figure 9, dual cistron constructs were made by inserting uidA in the Enterococcus faecium LMG15709 chromosome at the 3' end of several endogenous genes (gene X, gap and eno in this example; Figure 9). Hereby, rpmD of Enterococcus faecium was used as intergenic region between the endogenous genes of interest from Table 6 and uidA to identify sites that result in highest β-giucuronidase (GUS) activity (Figure 10).

[0208] Enterococcus faecium cultures were grown for 16 hours at 30°C in GM17 supplemented with thymidine. Cells of 1 ml culture were washed and resuspended in 1 ml demineralized water. Cells were disrupted with MP Biomedicals lysing matrix B and Fasprep-24 device at 6 m/s for 40 seconds. Tubes were centrifuged and a dilution series of the cell supernatant was made. GUS activity was measured by adding p-nitrophenyl substrate and β-mercaptoethanol which gives the solution a yellow colour upon presence of β-glucuronidase. GUS activity was measured at 405 nm and expressed relatively to reference Lactococcus lactis strain sAGX0090. All strains were treated in parallel.

[0209] Figure 10 shows relative GUS-activity of gene X>>rpmD>>uidA dual cistron constructs. GUS-activity is expressed relatively to reference strain sAGX0090 that carries the PhIIA>>uidA expression cassette and is indicated on the Y-axis. GUS-activity in all dual cistron strains was found to be higher than the reference strain.

[0210] In particular, GUS-activity in sAGX0270 (gap>>rpmD>>uidA) and sAGX0271 (eno>>rpmD>>uidA) was found to be 30.6 and 26.9 times higher when compared to sAGX0090, respectively.

[0211] These results clearly confirm that bicistronic expression allows enhanced protein expression levels over a wide variety of settings.

Example 9: Bicistronic expression of human interleukin-10 (hIL10) by Enterococcus faecium



[0212] The DNA coding sequence of the usp45 secretion leader of Lactococcus lactis (SS) was fused in frame to the DNA sequence of mature hIL10 to obtain secretion of hIL10. The [SS::hIL10] expression cassette was inserted, along with the rpmD intergenic region of Enterococcus faecium preceding SS::hIL10, as a second cistron downstream from gap (sAGX0279; Figure 11a). The hIL10 secretion capacity was quantified by ELISA to evaluate bicistronic expression of cargo in Enterococcus faecium. Enterococcus faecium sAGX0270 served as a negative control.

[0213] Strains were inoculated from single colony into 10 ml GM17 supplemented with 200 µM thymidine (GM17T) when needed and grown for 16 hours at 30°C. For the quantification of hIL10 secretion, these saturated overnight cultures were diluted 1/25 in 5 ml fresh GM17T medium and grown for 4 hours at 30°C. Cells were collected by centrifugation at 3220 x g for 10 minutes, resuspended in an equal amount BAM9T medium and cultured for another 3 hours at 30°C. BAM9T contains M9 salts, 0.5% aminoplasmal, 0.5% glucose, 25 mM NaHCO3, 25 mM Na2CO3, 2 mM MgSO4, 0.1 mM CaCl2 and 200 µM thymidine. Cells and culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. The amount of secreted human hIL10 in the culture supernatant was quantified by sandwich hIL10 ELISA. All strains were treated in parallel.

[0214] Figure 11b represents the quantification of human hIL10 secretion by Enterococcus faecium strains sAGX0270 and sAGX0279 The amount of secreted hIL10 was expressed as ng/109 CFU cells in 3 hours and indicated on the Y-axis. The figure clearly demonstrates that Enterococcus faecium strains comprising a bicistronic expression cassette are able to secrete considerable amounts of the cargo protein hIL10.

Example 10: Bicistronic expression of human interleukin-27 (hIL27) by Enterococcus faecium



[0215] The DNA coding sequence of the usp45 secretion leader of Lactococcus lactis (SS) was fused in frame to the DNA sequence of mature hIL27 to obtain secretion of hIL27. The [SS::hIL27] expression cassette was inserted, along with the rpmD intergenic region of Enterococcus faecium preceding SS::hIL27, as a second cistron downstream from gap (sAGX0317; Figure 12a). The hIL27 secretion capacity was quantified by ELISA to evaluate bicistronic expression of hIL27. Enterococcus faecium sAGX0270 served as a negative control,

[0216] Strains were inoculated from single colony into 10 ml GM17 supplemented with 200 µM thymidine (GM17T) and grown for 16 hours at 30°C. For the quantification of hIL27 secretion, these saturated overnight cultures were diluted 1/25 in 5 ml fresh GM17T medium and grown for 4 hours at 30°C. Cells were collected by centrifugation at 3220 x g for 10 minutes, resuspended in an equal amount BM9T medium and cultured for another 3 hours at 30°C. BM9T contains M9 salts, 0.5% casitone, 0.5% glucose, 25 mM NaHCO3, 25 mM Na2CO3, 2 mM MgSO4, 0.1 mM CaCl2 and 200 µM thymidine. Cells and culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. The amount of secreted human hIL27 in the culture supernatant was quantified by sandwich hIL27 ELISA (R&D systems). All strains were treated in parallel.

[0217] Figure 12b represents the quantification of human hIL27 secretion by Enterococcus faecium strains sAGX0270 and sAGX0317. The amount of secreted hIL27 was expressed as ng/109 CFU cells in 3 hours and indicated on the Y-axis. The figure clearly demonstrates that Enterococcus faecium strain sAGX0317 comprising a bicistronic expression cassette positioned downstream of the Enterococcus faecium gap gene is able to efficiently secrete considerable amounts of the exogenous protein hIL27.

Example 11: Bicistronic expression of CDP870 Fab by Enterococcus faecium



[0218] A dual cistron expression constructs was generated with heavy chain and light chain genes of CDP870 Fab. All expression units are located on the bacterial chromosome.

[0219] Figure 13a: CDP870 heavy and light chain Fab fusions to the Lactococcus lactis MG1363 usp45 secretion leader (SS) encoding sequences [SS::CDP870 VHCH1] and [SS::CDP870 VLCL] were inserted as a second and third cistron downstream from the Enterococcus faecium LMG15709 gap gene (sAGX0278). In sAGX0278, the intergenic region of Enterococcus faecium rpmD was used to couple SS::CD870 expression cassettes to gap. To avoid genetic instability, heavy and light chain genes were coupled through the intergenic region preceding Lactococcus lactis rpmD and different codon usage was used in the usp45 secretion signals of the two SS::CD870 expression cassettes The heavy expression cassette precedes the light chain expression cassette in sAGX0278.

[0220] For the quantification of CDP870 fab secretion, strains were inoculated from single colony into 10 ml GM17T and grown for 16 hours at 30°C. These saturated overnight cultures were diluted 1/25 in 5 ml fresh GM17T medium and grown for 4 hours at 30°C. Cells were collected by centrifugation at 3220 x g for 10 minutes, resuspended in an equal amount BAM9T medium and cultured for another 3 hours at 30°C. BAM9T contains M9 salts, 0.5% aminoplasmal, 0.5% glucose, 25 mM NaHCO3, 25 mM Na2CO3, 2 mM MgSO4, 0.1 mM CaCl2 and 200 µM thymidine. Cells and culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. Crude supernatants from strains carrying the individual constructs were prepared in parallel and were assayed for the presence of TNF binding activity. This was done by direct ELISA using human TNF as capture protein with Cimzia® (CDP870 fab linked to PEG) as a reference standard. CDP870 fab was detected by goat anti-human Fab antiserum and revealed by HRP conjugated donkey anti-goat IgG(H+L) antiserum. HRP activity was visualized by TMB substrate. Reaction was stopped after 30 minutes by adding HCI. Absorbance was measured at 450 nm with 595 nm as reference wavelength. All strains were treated in parallel.

[0221] Figure 13b reveals that both heavy chain and light chains were expressed by the multiple cistron construct in Enterococcus faecium, leading to the secretion of functional CDP870 anti-TNF Fab.

Example 12: Anti-hTNF producing L. lactis bacteria (according to the invention) protects against hTNF-induced intestinal damage in A20IEC-KO mice.


Generation of tissue-specific A20 deficient mice.



[0222] Conditional A20/tnfaip3 knockout mice, in which exons IV and V of tnfaip3 gene are flanked by two LoxP sites, were generated as described (Piguet et al., 1999, Lab Invest 79, 495-500). A20 floxed mice were crossedwith Villin-Cre transgenic mice generating IEC-specific A20 knockout mice (A20IEC-KO) (Madison et al., 2002, J Biol Chem 277, 33275-33283). Experiments were performed on mice backcrossed into the C57BL/6 genetic background for at least four generations.

In vivo TNF toxicity.



[0223] Mice were injected i.p. with different doses hTNF (50, 10, 8, 6, 4 and 2 µg hTNF/20 g body weight). E. coli-derived recombinant hTNF had a specific activity of 6.8 × 107 IU/mg. Human TNF was produced and purified to homogeneity in our laboratory, and endotoxin levels did not exceed 1 ng/mg of protein. hTNF injection in A20IEC-KO mice induces several pathological and immunological changes that are indicative of intestinal damage. Low dose hTNF does not induce severe systemic effects and lethality, but induces pro-inflammatory cytokine and chemokine expression which can be measured both in serum and homogenates of intestinal tissue. Mice were euthanized after 4 or 5 h for histological analysis. For therapeutic studies, A20IEC-KO mice received anti-TNF producing L. lactis bacteria (according to the invention) by oral gavage 5 times (5x 1010CFU with 30min interval) prior to an intraperitoneal injection with hTNF (2 µg and 6 µg hTNF/20 g body weight). Control groups were either treated with the parental L. lactis strain MG1363 or with bacterial medium BM9T (vehicle). In addition, a positive control group was treated with a single injection of Remicade (30 mg/kg). Body temperatures were monitored every hour.

Tissue sample preparation.



[0224] Freshly isolated colonic and ileal segments were flushed with PBS to remove the fecal content and subsequently flushed with formalin (4% formaldehyde in phosphate buffered saline (PBS)) and fixed by incubation overnight in a 10-fold excess of formalin at 4°C. The formalin was removed and intestines were washed twice with PBS prior to embedding in paraffin wax using standard methods.

Histology.



[0225] Tissue sections of 4 µm were cut and stained with hematoxylin/eosin using standard techniques. For combined Alcian Blue (AB) and PAS stainings, dewaxed sections were hydrated to distilled water and incubated in Alcian Bleu for 20 min. Sections were subsequently incubated in 1 % periodic acid for 10 min followed by incubation in Schiff's reagent for 10 min. Nuclei were counterstained with Mayer's Haematoxylin for 30 sec. Alkaline phosphatase detection was performed by incubation of dewaxed and hydrated tissue sections in NBT/BCIP solution in the dark (70µl NBT + 70µl BCIP + 4860µl Buffer A, NBT = 1.5 % Nitroblue Tetrazolium Chloride solution in 70% dimethyl formamide, BCIP = 1 % 5-bromo-4-Cloro-3-Indolyl Phosphatase in 100 % dimethyl formamide, Buffer A = 0.1M TrisHCl, 0.1M NaCl, 0.05M MgCI2, pH9.5). For immunochemistry, sections were dewaxed and incubated in Dako antigen retrieval solution and boiled for 20 min in a Pick cell cooking unit and cooled down for 2.5 h. Endogenous peroxidase activity was blocked by immersing slides in peroxidase-blocking buffer buffer (0.040 M citric acid, 0.121 M disodium hydrogen phosphate, 0.030 M sodium azide, 1.5% hydrogen peroxide) for 15 min at room temperature. Blocking buffer (1 % bovine serum albumin in PBS) was added to the slides for 30 min at room temperature. Primary antibodies (rabbit anti-lysozyme; 1:1,750 dilution - Dako; rabbit anti-mucin-2; 1:500 22) were added in blocking buffer and tissue sections were incubated overnight. Secondary antibody was added (polymer horseradish peroxidase-labelled anti- rabbit, Envision) for 30 min at room temperature. Peroxidase was detected by adding diaminobuteric acid (DAB) substrate for 10 min at room temperature and nuclei were counterstained with Mayer's haematoxylin for 2 min. Microscopic measurement of Paneth cell granule radii was done with Leica Image manager 500 software.

Quantification of cytokines.



[0226] Cytokines and chemokines in serum and tissue homogenates were quantified by Cytometric Bead Array kits (CBA) (BD Biosciences) on a FACS Calibur cytometer equipped with CellQuest Pro and CBA software (BD Biosciences).

Quantitative real-time PCR.



[0227] Ileal segments of 5 cm long were freshly isolated and flushed with PBS to remove the fecal content. One end was ligated and segments were filled with RNA lysis buffer (Aurum Total RNA Mini kit, Bio-Rad Laboratories) and incubated on ice for 5 min. RNA was purified from the lysate solution using the Aurum Total RNA Mini kit (Bio-Rad Laboratories). cDNA synthesis was performed using the iScript cDNA synthesis kit (Bio-Rad Laboratories) according to the manufacturer's instructions. 10 ng cDNA was used for quantitative PCR in a total volume of 10 µl with LightCycler 480 SYBR Green I Master Mix (Roche) and specific primers on a LightCycler 480 (Roche). Real-time PCR reactions were performed in triplicates. The following mouse-specific primers were used: ubiquitin forward,5'-AGGTCAAACAGGAAGACAGACGTA-3' (SEQ ID NO: 14); and ubiquitin reverse, 5'-TCACACCCAAGAACAAGCACA-3' (SEQ ID NO: 15). Lysozyme-P forward, 5'- GCCAAGGTCTAACAATCGTTGTGAGTTG-3' (SEQ ID NO: 16); Lysozyme-P reverse, 5'-CAGTCAGCCAGCTTGACACCACG-3' (SEQ ID NO: 17); Cryptidin-1 forward, 5'-TCAAGAGGCTGCAAAGGAAGAGAAC-3' (SEQ ID NO: 18); Cryptidin-1 reverse, 5'-TGGTCTCCATGTTCAGCGACAGC-3' (SEQ ID NO: 19).

Statistical analyses.



[0228] Results are expressed as the mean ± SEM. Statistical significance between experimental groups was assessed using an unpaired two-sample Student t-Test.

[0229] Characterization of anti-hTNF producing L. lactis bacteria to protect against hTNF-induced pathological and immunological alterations in A201EC-KO mice.

[0230] Both control groups injected with 2 µg hTNF showed a more drastic drop in body temperature compared to A20IEC-KO mice treated with anti-hTNF producing L. lactis bacteria (Fig. 14a, left panel). The protective effect of sAGX0220 treatment observed in mice treated with 2 µg hTNF could no longer be observed when mice were injected with a higher concentration of hTNF (6 µg), whereas Remicade treatment clearly had a protective effect (Fig. 14a, right panel). sAGX0220 pretreatment significantly reduced MCP-1, KC and IL-6 levels in ileal and colon homogenates and in serum of mice treated with either 2 µg hTNF, compared to vehicle-treated mice (Fig. 14b,c). However, there was a comparable reduction in mice treated with the parental L. lactis strain MG1363, indicating that the administration of bacteria on itself can already have a probiotic protective effect. Mice challenged with 6 µg hTNF showed a similar reduction in serum and tissue cytokine and chemokine levels upon sAGX0220 pretreatment, to the same extent as Remicade does (Fig. 14d,e). In this setting, however, the protective effect of the parental MG1363 strain is mostly lost (Fig. 14d,e).

Example 13: Passive immunization against Clostridium difficile-associated disease with toxin-neutralizing antibodies locally produced and secreted via Lactococcus lactis.


a) Gene synthesis of VLCL and VHCH1 of C. difficile toxin A and C. difficile toxin B neutralizing mAb



[0231] De novo gene synthesis (optimized for L. lactis codon usage) is performed based on the VH and VL amino acid sequence information according to a routine method (Stemmer et al., Gene 1995;164(1):49-53). This method makes use of synthetic 40-mer oligonucleotides that span the entire coding as well as the non-coding strand, in such way that every oligonucleotide from the coding strand will be 100% complementary with respectively the last and first 20 base pairs of two consecutive oligonucleotides in the non-coding strand, and vice versa.

[0232] Genetic information that encodes the secretion leader of L. lactis unidentified secreted 45-kDa protein (Usp45) is added to the 5' end of VLCL and VHCH1 genes.

[0233] To guarantee coordinated expression, these synthetic VLCL and VHCH1 genes are placed in tandem and joined by the rpmD intergenic region. This leads to the formation of functional VLCL >> VHCH1 operons. Also constructed are variants of the above described synthetic genes that also encode C-terminal E and FLAG peptide tags. This visualizes full size and/or potential degradation products, and enables the verification of light chain and heavy chain assembly and toxin binding.

[0234] The resulting gene constructs will be sequence verified.

b) Construction of L. lactis strains secreting toxin A/B neutralizing Fab: integration at the Usp45 locus



[0235] This task consists of the following stages:
  1. 1. Construction of integration vectors for the integration downstream the usp45 locus of
    • VLCL >> VHCH1 of C. difficile toxin A neutralizing Mab
    • VLCL >> VHCH1 of C. difficile toxin B neutralizing Mab
    • 3' E and FLAG tagged variants of the above

    The synthetic VLCL >> VHCH1 operons are flanked at the 5'end by 1 kb of the 3' end of the L. lactis usp45 gene followed by the rplN intergenic region. The VLCL >> VHCH1 operons are flanked at the 3' end by a 1 kb fragment of the 3' downstream flanking region of the L. lactis usp45 gene. Constructions are made by overlap PCR DNA annealing. The resulting plasmids are sequence verified.
  2. 2. The above generated integration plasmids are used for integration via translational coupling to the usp45 gene of L. lactis MG1363. Integration is performed by double homologous recombination at both 5' and 3' flanking regions (corresponding to 1kb regions flanking the 3' end of usp45), and verified by PCR and DNA sequencing.

c) Construction of L. lactis strains secreting toxin A/B neutralizing Fab: integration at the enoA locus



[0236] This task consists of the following stages:

1. Construction of integration vectors for the integration downstream of the enoA locus of

  • VLCL >> VHCH1 of C. difficile toxin A neutralizing Mab
  • VLCL >> VHCH1 of C. difficile toxin B neutralizing Mab
  • 3' E and FLAG tagged variants of the above

The synthetic VLCL >> VHCH1 operons from Task 7 are flanked at the 5'end by 1 Kb of the 3' end of the L. lactis enoA gene followed by the rplN intergenic region. The VLCL >> VHCH1 operonsare flanked at the 3' end by a 1 Kb fragment of the 3' downstream flanking region of the L. lactis enoA gene. Constructions are made by overlap PCR DNA annealing. The resulting plasmids are sequence verified.

2 The above generated integration plasmids are used for integration via translational coupling to the enoA gene of L. lactis MG1363. Integration is performed by double homologous recombination at both the 5' and 3' flanking regions (corresponding to 1kb regions flanking the 3' end of enoA), and verified by PCR and DNA sequencing.


d) Establishment of a TopAct™ compatible hamster model of CDAD



[0237] The hamster model of CDAD is a well-established model for the study of toxin-induced antibiotic-associated diarrhea and colitis. The most extensively studied model of C. difficile infection in hamsters is the primary challenge model. Briefly, hamsters are pretreated with clindamycin (10-30 mg/kg) orogastrically 24 hours prior to the administration of C. difficile spores to disrupt the normal colonic flora in the hamster. C. difficile spores (e.g. 100 spores of strain 630 or B1; see Goulding et al., Infect Immun 2009;77(12):5478-5485) are administered orogastrically, and the hamsters are observed (CDAD primary challenge model). Typically, 100% of hamsters succumb to disease between 36 and 72 hours after spore administration. Prior to mortality, symptoms of disease include diarrhea and weight loss. In general, the symptoms are much more severe than those seen in humans, but the hamster model responds to therapeutic maneuvers used in clinical disease, such as treatment with vancomycin, and is therefore widely used in the study of CDAD.

[0238] In order to simulate CDAD relapse control, a modified primary disease hamster model is used. Vancomycin protects hamsters from C. difficile disease, as it does in humans. When vancomycin treatment is discontinued, hamsters relapse with severe disease, but the attack rate varies. Briefly, hamsters are given a single dose of clindamycin followed by the orogastric administration of C. difficile strain B1 spores 1 day later. Vancomycin treatment began on the day of spore challenge or 24 hours later and continued daily for two to four subsequent days (CDAD relapse model). This protocol can be further optimized to ensure relapse after rescue with vancomycin.

[0239] To assess the benefit of toxin-neutralizing Fab, intestinally delivered by L. lactis, in preventing mortality in the primary and/or relapse model of infection in the hamster, it is important to document the impact of clindamycin and vancomycin on the growth and Fab production capacity of L. lactis. Therefore, in vitro/in vivo studies are performed to determine viability and metabolic activity of the Fab-secreting L. lactis strains.
  • In vitro evaluation: Fab production (via ELISA) and growth (via plating) from clindamycin/vancomycin-supplemented L. lactis cultures is compared to an antibiotics-free culture and to a culture supplemented with chloramphenicol (Cm) at 5 µg/ml. At this concentration, Cm is a known inhibitor of protein synthesis and growth, to which L. lactis is sensitive.
  • In vivo evaluation: Fab production (via ELISA) and viability (via plating) is determined in the small/large intestine following oral gavage of hamsters and concomitant treatment with different doses of clindamycin/vancomycin.


[0240] These evaluations allow designing and adapting the hamster model (challenge and relapse) of CDAD that is well-suited for the evaluation of the L. lactis delivery system for their preventive and curative effects: this is using (lower) clindamycine (and vancomycine) concentrations and/or a different cocktail of antibiotics demonstrating susceptibility to C. difficile infection without negative effect on L. lactis viability and metabolic activity.

e) Validation of the hamster model of CDAD.



[0241] In the hamster primary challenge model, Syrian golden hamsters (70 to 80 g) are given different oral doses (qd, bid or tid) of the selected anti-toxin A/B-secreting L. lactis (anti-toxin A and anti-toxin B alone and combined) or 1 ml anti-toxin A/B mAb (as a positive control) intraperitoneally for 4 days beginning 3 days prior to the administration of C. difficile spores. Clindamycin (dose or another cocktail of antibiotics as defined above) is administered orogastrically 24 hours prior to C. difficile spore challenge using a standard small animal feeding needle. Animals are observed for morbidity and mortality, intestinal tissues are scored for histological and macroscopic damage, and C difficile toxin production in luminal contents and feces is determined.

[0242] In the hamster relapse model, Syrian golden hamsters (70 to 80 g) are given clindamycin (dose or another cocktail of antibiotics as defined above) orogastrically and 24 hours later challenged with C. difficile B1 spores orogastrically. At the time of spore administration or 24 hours later, vancomycin treatment (dose as defined above) orogastrically starts and continues daily for a total of 2-4 days. Beginning 1, 2, 3, 4 or 5 days following vancomycin treatment, different oral doses (qd, bid or tid) of the selected anti-toxin A/B-secreting L. lactis (anti-toxin A and anti-toxin B alone and combined) or 1 ml anti-toxin A/B mAb (as a positive control, intraperitoneally) is administered for a total of 5-10 days. Animals are observed for morbidity and mortality, intestinal tissues are scored for histological and macroscopic damage, and C. difficile toxin production in luminal contents and feces is determined.

[0243] It can be concluded that the gram-positive bacteria according to the invention can effectively be used for immunizing against CDAD. In particular, the gram-positive bacteria according to the invention can prevent the occurrence of CDAD, prevent relapse of CDAD, as well as treat CDAD.

Example 14: Mouth rinse powder for reconstitution:



[0244] The Drug Substance (DS) of a mouth rinse formulation is a homogeneous, lyophilized powder of an engineered strain according to the invention and mixed with cryoprotectants (dextrin, sorbitol and sodium glutamate).

[0245] The production process for the Drug Substance includes the following successive steps: fermentation, biomass concentration (by diafiltrationor centrifugation), formulation with cryoprotectants, filling into suitable trays and bulk lyophilization. Homogenization and sieving of the lyophilized cake is performed to produce a homogeneous powder (the Drug Substance) suitable for mixing with excipient and filling into the desired pharmaceutical dosage form.

[0246] The mouth rinse Drug Product (DP) powder for reconstitution consists of the freeze-dried L. lactis bacteria, mixed with mannitol as an excipient and presented as a (compressed) powder. The clinical formulation is an oral, topical administration in the form of a mouth rinse. This mouth rinse suspension is prepared by reconstitution of the DP into a selected solution.

[0247] The production process of the mouth rinse powder for reconstitution includes a series of successive steps:
  • mixing of Bulk DS with mannitol,
  • compressing of 500 mg the DP powder mix in 500 mg dispersible powder compacts,
  • filling of the compressed powder in glass vials,
  • closing of the vials with tamper-evident, child-resistant screw caps, and
  • packaging of vials in aluminum (Alu) bags.

Example 15: Bicistronic expression of CDP870



[0248] Dual cistron expression constructs were generated with heavy chain and light chain of CDP870 anti-TNF Fab. All expression units are located on the bacterial chromosome.

[0249] Figure 15 A, schematic overview of CDP870 anti-TNF expression units in various strains: CDP870 light and heavy chain Fab fusions to usp45 secretion leader encoding sequences (SS::CDP870 VLCL and SS::CDP870 VHCH1) were inserted as a second and third cistron downstream from usp45 (sAGX0309, sAGX0319), enoA (sAGX0275) and gapB (sAGX0323, sAGX0326). In these strains, rpmD was used to couple SS::CD870 genes to usp45, enoA or gapB respectively. To avoid genetic instability, light and heavy chain genes were coupled through the intergenic region preceding rplN. In figure 15 B and C 4 identical clones of sAGX0326 (clone 1-4) were analyzed and reported. Strains were processed in parallel throughout the experiments.

[0250] For the visualization and quantification of CDP870 anti-hTNF secretion, strains were inoculated from single colony into 10 ml GM17T (Difco™M17, BD, Sparks, MD, + 0,5% glucose + 200 µM thymidine) and grown for 16 hours at 30°C. Bacteria from these saturated overnight cultures were collected by centrifugation at 3220 x g for 10 minutes and resuspended in 10 ml fresh GM17T medium and grown for 2 hours at 30°C. Bacteria and crude culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. Crude supernatants from all strains were prepared in parallel and split up per strain for analysis (Figure 15 B and C).

[0251] Total protein content of 5ml volumes of crude culture supernatants was extracted with phenol, precipitated with ethanol and resuspended in SDS-PAGE sample buffer. Equivalents of 1ml of crude culture supernatants were analyzed by western blot using goat anti-human Fab as a primary antiserum and revealed by rabbit anti-goat AP and NBT/BCIP staining (Figure 15 B; strains are indicated at the right of respective lanes).

[0252] Crude supernatants from strains carrying the individual constructs were assayed for the presence of hTNF binding activity. This was done by direct ELISA using hTNF as capture protein with Cimzia as a reference standard. VLCL portions were detected by goat anti-human IgG antiserum and revealed by horseradish peroxydase (HRP) conjugated anti-goat antiserum. HRP activity was measured by colorimetric assay. Data are presented in Figure 15 C, strains are indicated underneath respective bars.

[0253] Figure 15 (B and C) reveal that both heavy chain and light chains were highly expressed by the dual cistron constructs, leading to high levels of functional CDP870 anti-TNF Fab. Figure 15 (B and C) reveals that CDP870 anti-TNF expression slightly increased when heavy and light chain genes were inserted as a second and third cistron downstream from enoA when compared to insertion downstream of usp45. Figure 15 (B and C) further reveals that CDP870 anti-TNF expression was substantially increased when heavy and light chain genes were inserted as a second and third cistron downstream from gapB when compared to insertion downstream of usp45 or enoA.

[0254] For the determination of specific hTNF neutralizing capacity (biological activity per quantity of TNF binding protein), strains were inoculated from single colony into 5 ml GM17T and grown for 16 hours at 30°C. Bacteria from these saturated overnight cultures were collected by centrifugation at 3220 x g for 10 minutes and resuspended in 5 ml BM9T medium and grown for 2 hours at 30°C. Bacteria and crude culture supernatants were separated by centrifugation at 3220 x g for 10 minutes. Crude supernatants from strains carrying the individual strains were prepared in parallel and split up per strain for analysis (Figure 15 D and E).

[0255] Crude supernatants from strains carrying the individual constructs were assayed for the presence of TNF binding activity. This was done by direct ELISA using human TNF as capture protein with Cimzia as a reference standard. VLCL portions were detected by goat anti-human IgG antiserum and revealed by horseradish peroxydase (HRP) conjugated anti-goat antiserum. HRP activity was measured by colorimetric assay. All strains were treated in parallel. Data are presented in Figure 15 D, strains are indicated underneath respective bars.

[0256] Crude supernatants from strains carrying the individual constructs were assayed for the presence of TNF neutralizing activity. This was done by incubation of hTNF susceptible WEHI cells with human TNF and addition of anti-TNF. Anti-TNF will scavenge hTNF and will protect WEHI cells from cell death. A ½ dilution series of the crude supernatants as well as reference standard (Cimzia at 63 ng/ml) were added to the cell cultures subjected to hTNF. The impact on cell death was determined. Data are presented in Figure 15 E, strains are indicated underneath respective bars.

[0257] Figure 15 D reveals that both heavy chain and light chains were highly expressed by the dual cistron constructs, leading to high levels of functional CDP870 anti-TNF Fab. Figure 15 D further reveals that CDP870 anti-TNF expression substantially increased when heavy and light chain genes were inserted as a second and third cistron downstream from gapB when compared to insertion downstream of usp45.

[0258] Figure 15 D and E show that specific TNF neutralizing capacity (biological activity per quantity of TNF binding protein) of CDP870 anti-TNF in the crude culture supernatants of strains sAGX0323 and sAGX0326 is identical to that of Cimzia.

Example 16: Efficacy of L. lactis secreting anti-hTNFα Fab fragment



[0259] The experimental set up is based on the Tg1278TNFko mouse, a transgenic mouse with normally regulated human TNF expression in the absence of mouse TNF (Keffer et al. EMBO.J 10, 4025-4031, 1991). Colitis was induced by rectal administration challenge of 4% TNBS in 40% ethanol after one cutaneous presensitization. Briefly, mice were sensitized 7 days (Day -7) prior intrarectal challenge by applying 1 volume 5% TNBS + 4 volumes 4:1 acetone:olive oil to a shaved 1.5 x 1.5 cm skin area on the back. On the day of the challenge (Day 0), mice were first anesthetized with ketamine/xylazine, subsequently 100 µl 4%TNBS/40%EtOH was administered per rectum by a flexible catheter inserted 4 cm into the rectum. To ensure equal distribution of the enema within the colon, mice were held in a vertical position for 30 seconds directly after the rectal challenge.

[0260] Treatment was initiated 1 day before the rectal TNBS challenge (Day -1) and was continued for another 4 days (Day +3). Three groups of mice received once daily intragastric inoculations with 1010 CFU of MG1363 (negative control), 1010 CFU sAGX0309, or 10 µg Cimzia (positive control). Starting from Day 0 and on a daily basis, mice were monitored for body weight, morbidity and survival. On Day +3 mice were sacrificed and colon samples and serum were collected for histology (colon) and cytokine (colon and serum) analysis.

[0261] Treatment with a strain according to an embodiment of the invention (anti-hTNF-secreting L. lactis strain sAGX0309) resulted in an enhanced survival (Figure 16 and Table 7), in comparison with the wild type L. lactis strain MG1363 and surprisingly even a higher survival percentage than mice treated with Cimzia.
Table 7
SURVIVALL. lactis sAGX0309L. Lactis MG1363Cimzia
Day 1 100% (7/7) 100% (9/9) 100% (9/9)
Day 2 86% (6/7) 89% (8/9) 89% (8/9)
Day 3 86% (6/7) 56% (5/9) 78% (7/9)


[0262] Body weight of the mice was also followed during treatment, and is depicted in Figure 17. From Figure 17, it is evident that weight loss is lower after treatment with a strain according to an embodiment of the invention in comparison with treatment with Cimzia.

[0263] The histological status of the colon was also analyzed and a histological score was attributed according to Table 8. The results are indicated in Figure 18. From Figure 18, a significant improvement in the histological score, and hence a diminished colitic pathology, is evident after treatment with a strain according to an embodiment of the invention.
Table 8
Histological scoreDescription
0 No inflammation; no epithelial dammage
1 Inflammation in the mucosa around the crypt bases; no epithelial dammage
2 Inflammation in the submucosa; mild epithelial dammage with loss of goblet cells
3 Inflammation in the submucosa; local loss of crypt architecture
4 Inflammation in the submucosa; loss of crypt architecture in extended areas of the mucosa


[0264] Finally, from Figure 19, it is apparent that treatment with a strain according to an embodiment of the invention resulted in a suppression of colonic proinflammatory cytokine secretion.

SEQUENCE LISTING



[0265] 

<110> Intrexon Actobiotics NV

<120> Polycistronic expression system for bacteria

<130> INX16607PCTEPD1

<140> Not yet assigned
<141> 2012-06-01

<150> EP 12 729 396.7
<151> 2012-06-01

<150> PCT/EP2012/060431
<151> 2012-06-01

<150> 11168495.7
<151> 2011-06-01

<150> 11173588.2
<151> 2011-07-12

<160> 19

<170> PatentIn version 3.3

<210> 1
<211> 5
<212> DNA
<213> Lactococcus lactis

<400> 1
taatg   5

<210> 2
<211> 9
<212> DNA
<213> Lactococcus lactis

<400> 2
taatccatg   9

<210> 3
<211> 16
<212> DNA
<213> Lactococcus lactis

<400> 3
taaggaggaa aaaatg   16

<210> 4
<211> 21
<212> DNA
<213> Lactococcus lactis

<400> 4
taatagagga ggaaaatcgt g   21

<210> 5
<211> 24
<212> DNA
<213> Lactococcus lactis

<400> 5
taagaaggga gataagtaag aatg   24

<210> 6
<211> 24
<212> DNA
<213> Lactococcus lactis

<400> 6
taaggaaagg ggtaattaaa catg   24

<210> 7
<211> 28
<212> DNA
<213> Lactococcus lactis

<400> 7
taagcaaaac taggaggaat atagcatg   28

<210> 8
<211> 5
<212> DNA
<213> Enterococcus faecium

<400> 8
taatc   5

<210> 9
<211> 17
<212> DNA
<213> Enterococcus faecium

<400> 9
taaggaggac aacaata   17

<210> 10
<211> 18
<212> DNA
<213> Enterococcus faecium

<400> 10
taataggagg gaatttca   18

<210> 11
<211> 24
<212> DNA
<213> Enterococcus faecium

<400> 11
ttagaagaag gaggaatacc attc   24

<210> 12
<211> 30
<212> DNA
<213> Enterococcus faecium

<400> 12
taaaagttta aggaaggagg gtcttactga   30

<210> 13
<211> 34
<212> DNA
<213> Enterococcus faecium

<400> 13
taatcaagta gaatctacaa ggaggtgtct ttaa   34

<210> 14
<211> 24
<212> DNA
<213> Artificial

<220>
<223> Primer

<400> 14
aggtcaaaca ggaagacaga cgta   24

<210> 15
<211> 21
<212> DNA
<213> Artificial

<220>
<223> Primer

<400> 15
tcacacccaa gaacaagcac a   21

<210> 16
<211> 28
<212> DNA
<213> Artificial

<220>
<223> Primer

<400> 16
gccaaggtct aacaatcgtt gtgagttg   28

<210> 17
<211> 23
<212> DNA
<213> Artificial

<220>
<223> Primer

<400> 17
cagtcagcca gcttgacacc acg   23

<210> 18
<211> 25
<212> DNA
<213> Artificial

<220>
<223> Primer

<400> 18
tcaagaggct gcaaaggaag agaac   25

<210> 19
<211> 23
<212> DNA
<213> Artificial

<220>
<223> Primer

<400> 19
tggtctccat gttcagcgac agc   23




Claims

1. A gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising an endogenous gene and one or more exogenous genes, wherein said endogenous gene and said one or more exogenous genes are transcriptionally controlled by a promoter endogenous to the gram-positive bacterium, wherein said promoter is

(i) a ribosomal gene promoter selected from the group consisting of:

(a) an rpmD promoter,

(b) an rpsD promoter,

(c) an rpsL promoter,

(d) an rpsG promoter,

(e) an rplR promoter,

(f) an rpsE promoter,

(g) an rpsK promoter,

(h) an rplJ promoter,

(i) an rplL promoter,

(j) an rpsB promoter,

(k) an rplD promoter,

(l) an rplW promoter,

(m) an rplB promoter,

(n) an rplO promoter,

(o) an rplK promoter,

(p) an rpsH promoter,

(q) an rpsM promoter,

(r) an rpsS promoter,

(s) an rplU promoter,

(t) an rplV promoter,

(u) an rplP promoter

(v) an rplN promoter,

(w) an rpsJ promoter,

(x) an rplX promoter,

(y) an rplE promoter,

(z) an rplF promoter, and

(aa) an rplM promoter;

(ii) a glycolysis gene promoter promoter selected from the group consisting of:

(a) an fbaA promoter, and

(b) a pgk promoter; or

(iii) a dpsA promoter

of said gram-positive bacterium.
 
2. A recombinant nucleic acid comprising a polycistronic expression unit, said polycistronic expression unit comprising a gene endogenous to a gram-positive bacterium and one or more genes exogenous to the gram-positive bacterium, wherein said endogenous gene and said one or more exogenous genes are transcriptionally controlled by a promoter endogenous to the gram-positive bacterium, wherein said promoter is

(i) a ribosomal gene promoter selected from the group consisting of:

(a) an rpmD promoter,

(b) an rpsD promoter,

(c) an rpsL promoter,

(d) an rpsG promoter,

(e) an rplR promoter,

(f) an rpsE promoter,

(g) an rpsK promoter,

(h) an rplJ promoter,

(i) an rplL promoter,

(j) an rpsB promoter,

(k) an rplD promoter,

(l) an rplW promoter,

(m) an rplB promoter,

(n) an rplO promoter,

(o) an rplK promoter,

(p) an rpsH promoter,

(q) an rpsM promoter,

(r) an rpsS promoter,

(s) an rplU promoter,

(t) an rplV promoter,

(u) an rplP promoter

(v) an rplN promoter,

(w) an rpsJ promoter,

(x) an rplX promoter,

(y) an rplE promoter,

(z) an rplF promoter, and

(aa) an rplM promoter;

(ii) a glycolysis gene promoter promoter selected from the group consisting of:

(a) an fbaA promoter, and

(b) a pgk promoter; or

(iii) a dpsA promoter

of said gram-positive bacterium.
 
3. The gram-positive bacterium according to claim 1 or the recombinant nucleic acid according to claim 2, wherein said promoter is an rpmD promoter.
 
4. A vector comprising the recombinant nucleic acid of claims 2 or 3.
 
5. The gram-positive bacterium according to claim 1 or the recombinant nucleic acid according to claim 2, wherein said one or more exogenous genes is transcriptionally coupled to the 3' end of said endogenous gene.
 
6. The gram-positive bacterium or the recombinant nucleic acid according to claim 4, wherein one of the said exogenous genes is the most 3' gene of the polycistronic expression unit.
 
7. The gram-positive bacterium according to claims 1 or 3, wherein the endogenous gene is located in its native chromosomal locus in the gram-positive bacterium.
 
8. The gram-positive bacterium according to claim 7, wherein the endogenous gene is transcriptionally coupled to the one or more exogenous genes by chromosomally integrating the one or more exogenous genes into said locus, preferably by chromosomally integrating the one or more exogenous genes 3' of the endogenous gene into said locus.
 
9. the gram-positive bacterium according to any one of claims 1, 3 or 5 to 8, or the recombinant nucleic acid according to any one of claims 2, 3, 5 or 6, wherein said endogenous gene and said one or more exogenous genes are transcriptionally coupled by an intergenic region or intergenic regions active in the gram-positive bacterium, wherein said intergenic region or intergenic regions is selected from the group consisting of:

(a) sequences comprising or consisting of any of SEQ ID NOs: 1-13;

(b) sequences displaying one mismatch or a deletion or insertion of one nucleotide vs. SEQ ID NO: 1, SEQ ID NO: 2 or SEQ ID NO: 8;

(c) sequences displaying one, two or three mismatches, or a deletion or insertion of one, two or three nucleotides vs. SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 9 or SEQ ID NO: 10; or

(d) sequences displaying one, two, three or four mismatches or a deletion or insertion of one, two, three or four nucleotides vs. SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 11, SEQ ID NO: 12 or SEQ ID NO: 13.


 
10. The gram-positive bacterium or the recombinant nucleic acid according to claim 8, wherein the intergenic region or regions is endogenous to said gram-positive bacterium.
 
11. The gram-positive bacterium or the recombinant nucleic acid according to claim 10, wherein said intergenic region is selected from anyone of SEQ ID NOs: 1-13.
 
12. The gram-positive bacterium or the recombinant nucleic acid according to claim 11, wherein said intergenic region comprises the sequence of SEQ ID NO: 3 or SEQ ID NO: 9.
 
13. The gram-positive bacterium according to any one of claims 1, 3 or 5-12 or the recombinant nucleic acid according to any one of claims 2, 3, 5, 6 or 9-12, wherein said one or more exogenous genes encodes a product, which product is a protein, polypeptide and/or peptide.
 
14. The gram-positive bacterium or the recombinant nucleic acid according to claim 13, wherein said one or more exogenous genes are translationally coupled to a nucleic acid sequence encoding a secretion signal.
 
15. The gram-positive bacterium or the recombinant nucleic acid according to claim 14, wherein said secretion signal is a Lactococcus Usp45 secretion signal.
 
16. The gram-positive bacterium or the recombinant nucleic acid according to any one of claims 13-15, wherein said protein, polypeptide and/or peptide has a therapeutic or preventive effect in a subject.
 
17. The gram-positive bacterium according to any one of claims 1, 3 or 5-12 or the recombinant nucleic acid according to any one of claims 2, 3, 5, 6 or 9-12, wherein said one or more exogenous genes encodes a product, which product is an antigen for inducing immunity or immunotolerance, a non-vaccinogenic therapeutically active polypeptide, an antibody or a functional fragment thereof such as Fab, a fusion protein or a multimeric protein.
 
18. The gram-positive bacterium or the recombinant nucleic acid according to any one of claims 13-17, wherein said protein, polypeptide and/or peptide is selected from the group consisting of:

(i) interleukin-10 (IL-10);

(ii) trefoil factor 1 (TFF1);

(iii) pro-insulin (ins); and

(iv) interleukin-27 (IL-27).


 
19. The gram-positive bacterium or the recombinant nucleic acid according to claim 17, wherein said one or more exogenous genes encode a single domain antibody.
 
20. The gram-positive bacterium or the recombinant nucleic acid according to claim 17, wherein said one or more exogenous genes encode an anti-TNFa antibody, preferably an anti-TNFa antibody fragment, more preferably an anti-TNFa single antibody variable domain.
 
21. The gram-positive bacterium or the recombinant nucleic acid according to any one of claims 1, 2, 19 or 20, wherein one exogenous gene encodes the light chain (VL) of an antibody or a functional fragment thereof, and another exogenous gene encodes the heavy chain (VH) of the antibody or a functional fragment thereof, more preferably wherein the functional fragment is Fab.
 
22. The gram-positive bacterium or recombinant nucleic acid according to claim 21, wherein the exogenous gene encoding VL or a functional fragment thereof is transcriptionally coupled to the 3' end of the exogenous gene encoding VH or a functional fragment thereof.
 
23. The gram-positive bacterium or the recombinant nucleic acid according to any one of claims 13-22, for use as a medicament, preferably for use in administration or delivery of said product to a subject.
 
24. The gram-positive bacterium or the recombinant nucleic acid for the use according to claim 23, wherein the therapeutic polypeptide is delivered to a human or animal, and wherein:

(a) the disease is an inflammatory bowel disease, preferably Crohn's disease or ulcerative colitis;

(b) the disease is an autoimmune disease, preferably psoriasis, rheumatoid arthritis or lupus erythematosus;

(c) the disease is an allergic disease, preferably asthma or a food allergy;

(d) the disease is celiac disease;

(e) the disease is a neurological disorder, preferably Alzheimer's disease, Parkinson's disease or amyotrophic lateral sclerosis;

(f) the disease is cancer;

(g) the disease is osteoporosis;

(h) the disease is diabetes;

(i) the disease is cardiovascular disease;

(j) the disease is atherosclerosis;

(k) the disease is hemophilia;

(l) the disease is degenerative liver disease;

(m) the disease is a pulmonary disease, preferably cystic fibrosis;

(n) the disease is obesity;

(o) the disease is a pathogen infection, preferably a viral or bacterial infection; or

(p) the disease is an infectious disease, preferably Clostridium dificile associated disease (CDAD).


 
25. The gram-positive bacterium or the recombinant nucleic acid for the use according to claim 24, wherein:

(a) the disease is an inflammatory bowel disease, preferably Crohn's disease or ulcerative colitis, and the said one or more exogenous genes encodes IL-1ra, IL-10, IL-27 or trefoil peptides;

(b) the disease is an autoimmune disease, preferably psoriasis, rheumatoid arthritis or lupus erythematosus, and the said one or more exogenous genes encodes IL-1ra, IL-27, IL-10 or the relevant auto-antigen;

(c) the disease is an allergic disease, preferably asthma or a food allergy, and the said one or more exogenous genes encodes the relevant allergen;

(d) the disease is celiac disease, and the said one or more exogenous genes encodes gluten allergens;

(e) the disease is a neurological disorder including, preferably Alzheimer's disease, Parkinson's disease or amyotrophic lateral sclerosis, and the said one or more exogenous genes encodes brain derived neurotropic factor or ciliary neurotropic factor;

(f) the disease is cancer, and the said one or more exogenous genes encodes IL-1, colony stimulating factors or interferon-W;

(g) the disease is osteoporosis, and the said one or more exogenous genes encodes transforming growth factor f3;

(h) the disease is diabetes, and the said one or more exogenous genes encodes insulin;

(i) the disease is cardiovascular disease, and the said one or more exogenous genes encodes tissue plasminogen activator;

(j) the disease is atherosclerosis, and the said one or more exogenous genes encodes cytokines and/or cytokine antagonists;

(k) the disease is hemophilia, and the said one or more exogenous genes encodes clotting factors;

(l) the disease is degenerative liver disease, and the said one or more exogenous genes encodes hepatocyte growth factor or interferon a;

(m) the disease is a pulmonary disease, preferably cystic fibrosis, and the said one or more exogenous genes encodes alpha antitrypsin; or

(n) the disease is an infectious disease, preferably Clostridium dificile associated disease (CDAD), and the said one or more exogenous genes encodes a toxin-neutralizing antibody.


 
26. The gram-positive bacterium according to any one of claims 1, 3 or 5-22 or the recombinant nucleic acid according to any one of claims 2, 3, 5, 6 or 9-22, wherein the gram-positive bacterium is a lactic acid bacterium.
 
27. The gram-positive bacterium or the recombinant nucleic acid according to claim 26, wherein the lactic acid bacterium is Lactococcus, Lactobacillus, or Enterococcus, preferably Lactococcus lactis or Enterococcus faecium, or where the gram-positive bacterium is a Bifidobacterium.
 
28. A pharmaceutical composition comprising the gram-positive bacterium according to any one of claims 1, 3, 5-22, 26 or 27, and a pharmaceutically acceptable carrier.
 
29. The pharmaceutical composition of claim 28 for use as a medicament, preferably for use in administration or delivery of the product encoded by the said one or more exogenous genes to a subject.
 
30. Use of the gram-positive bacterium or the recombinant nucleic acid according to any one of claims 9 to 12, for polycistronic expression of one or more genes, open reading frames or coding sequences exogenous to said gram-positive bacterium and one or more genes, open reading frame or coding sequences endogenous to said gram-positive bacterium.
 
31. A method for effecting polycistronic expression of the one or more exogenous genes or for effecting polycistronic expression of the one or more endogenous genes and one or more exogenous genes in a gram-positive bacterium, comprising the step of introducing the recombinant nucleic acid according to claim 2 or the vector according to claim 4, to said gram-positive bacterium.
 
32. A method for generating a gram-positive bacterium capable of expressing one or more exogenous proteins, comprising the step of introducing the recombinant nucleic acid according to claim 2 or the vector according to claim 4 in said gram-positive bacterium such as to be transcribed in a polycistronic mRNA.
 
33. Agram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising, in 5' to 3' order:

(i) the gapB promoter endogenous to said gram positive bacterium;

(ii) the gapB gene endogenous to said gram positive bacterium; and

(iii) the exogenous gene human trefoil factor coupled to the Lactococcus Usp45 secretion signal (SS:TFF1),

wherein the gapB gene is transcriptionally coupled to SS:TFF1 via the intergenic region preceding rpmD in the said gram positive bacterium, wherein the intergenic region preceding rpmD comprises the sequence of SEQ ID NO: 3 or SEQ ID NO: 9.
 
34. A gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising, in 5' to 3' order:

(i) the usp45 promoter endogenous to said gram positive bacterium;

(ii) the usp45 gene endogenous to said gram positive bacterium; and

(iii) the exogenous gene human trefoil factor coupled to the Lactococcus Usp45 secretion signal (SS:ins),

wherein the usp45 gene is transcriptionally coupled to SS:ins via the intergenic region preceding rpmD in the said gram positive bacterium, wherein the intergenic region preceding rpmD comprises the sequence of SEQ ID NO: 3 or SEQ ID NO: 9.
 
35. A gram-positive bacterium comprising a polycistronic expression unit, said polycistronic expression unit comprising, in 5' to 3' order:

(i) the enoA promoter endogenous to said gram positive bacterium;

(ii) the enoA gene endogenous to said gram positive bacterium; and

(iii) the exogenous gene human trefoil factor coupled to the Lactococcus Usp45 secretion signal (SS:ins),

wherein the usp45 gene is transcriptionally coupled to SS:ins via the intergenic region preceding rpmD in the said gram positive bacterium, wherein the intergenic region preceding rpmD comprises the sequence of SEQ ID NO: 3 or SEQ ID NO: 9.
 
36. The gram-positive bacterium according to any one of claims 33-35, wherein said polycistronic expression unit is located at the locus endogenous to the promoter.
 


Ansprüche

1. Grampositives Bakterium, umfassend eine polycistronische Expressionseinheit, wobei die polycistronische Expressionseinheit ein endogenes Gen und ein oder mehrere exogene Gene umfasst, wobei das endogene Gen und das eine oder die mehreren exogenen Gene durch einen für das grampositive Bakterium endogenen Promotor transkriptionell gesteuert werden, wobei der Promotor

(i) ein ribosomaler Genpromotor, ausgewählt aus der Gruppe, bestehend aus:

(a) einem rpmD-Promotor,

(b) einem rpsD-Promotor,

(c) einem rpsL-Promotor,

(d) einem rpsG-Promotor,

(e) einem rplR-Promotor,

(f) einem rpsE-Promotor,

(g) einem rpsK-Promotor,

(h) einem rplJ-Promotor,

(i) einem rplL-Promotor,

(j) einem rpsB-Promotor,

(k) einem rplD-Promotor,

(l) einem rplW-Promotor,

(m) einem rplB-Promotor,

(n) einem rplO-Promotor,

(o) einem rplK-Promotor,

(p) einem rpsH-Promotor,

(q) einem rpsM-Promotor,

(r) einem rpsS-Promotor,

(s) einem rplU-Promotor,

(t) einem rplV-Promotor,

(u) einem rplP-Promotor

(v) einem rplN-Promotor,

(w) einem rpsJ-Promotor,

(x) einem rplX-Promotor,

(y) einem rplE-Promotor,

(z) einem rplF-Promotor und

(aa) einem rplM-Promotor;

(ii) ein Glycolysegenpromotor, ausgewählt aus der Gruppe, bestehend aus:

(a) einem fbaA-Promotor und

(b) einem pgk-Promotor; oder

(iii) ein dpsA-Promotor

von dem grampositiven Bakterium ist.
 
2. Rekombinante Nukleinsäure, umfassend eine polycistronische Expressionseinheit, wobei die polycistronische Expressionseinheit ein für ein grampositive Bakterium endogenes Gen und ein oder mehrere für das grampositive Bakterium exogene Gene umfasst, wobei das endogene Gen und das eine oder die mehreren exogenen Gene durch einen für das grampositive Bakterium endogenen Promotor transkriptionell gesteuert werden, wobei der Promotor

(i) ein ribosomaler Genpromotor, ausgewählt aus der Gruppe, bestehend aus:

(a) einem rpmD-Promotor,

(b) einem rpsD-Promotor,

(c) einem rpsL-Promotor,

(d) einem rpsG-Promotor,

(e) einem rplR-Promotor,

(f) einem rpsE-Promotor,

(g) einem rpsK-Promotor,

(h) einem rplJ-Promotor,

(i) einem rplL-Promotor,

(j) einem rpsB-Promotor,

(k) einem rplD-Promotor,

(l) einem rplW-Promotor,

(m) einem rplB-Promotor,

(n) einem rplO-Promotor,

(o) einem rplK-Promotor,

(p) einem rpsH-Promotor,

(q) einem rpsM-Promotor,

(r) einem rpsS-Promotor,

(s) einem rplU-Promotor,

(t) einem rplV-Promotor,

(u) einem rplP-Promotor

(v) einem rplN-Promotor,

(w) einem rpsJ-Promotor,

(x) einem rplX-Promotor,

(y) einem rplE-Promotor,

(z) einem rplF-Promotor und

(aa) einem rplM-Promotor;

(ii) ein Glycolysegenpromotor, ausgewählt aus der Gruppe, bestehend aus:

(a) einem fbaA-Promotor und

(b) einem pgk-Promotor; oder

(iii) ein dpsA-Promotor

von dem grampositiven Bakterium ist.
 
3. Grampositives Bakterium nach Anspruch 1 oder die rekombinante Nukleinsäure nach Anspruch 2, wobei der Promotor ein rpmD-Promotor ist.
 
4. Vektor, umfassend die rekombinante Nukleinsäure nach Ansprüchen 2 oder 3.
 
5. Grampositives Bakterium nach Anspruch 1 oder die rekombinante Nukleinsäure nach Anspruch 2, wobei das eine oder die mehreren exogenen Gene transkriptionell an das 3'-Ende des endogenen Gens gekoppelt ist.
 
6. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 4, wobei eins der exogenen Gene das am weitesten 3' liegende Gen der polycistronischen Expressionseinheit ist.
 
7. Grampositives Bakterium nach Ansprüchen 1 oder 3, wobei das endogene Gen in seinem nativen chromosomalen Locus in dem grampositiven Bakterium lokalisiert ist.
 
8. Grampositives Bakterium nach Anspruch 7, wobei das endogene Gen durch chromosomales Integrieren des einen oder der mehreren exogenen Gene transkriptionell an das eine oder die mehreren exogenen Gene in den Locus gekoppelt ist, vorzugsweise durch chromosomales Integrieren des einen oder der mehreren exogenen Gene 3' des endogenen Gens in den Locus.
 
9. Grampositives Bakterium nach einem der Ansprüche 1, 3 oder 5 bis 8, oder die rekombinante Nukleinsäure nach einem der Ansprüche 2, 3, 5 oder 6, wobei das endogene Gen und das eine oder die mehreren exogenen Gene durch eine in dem grampositiven Bakterium aktive intergenische Region oder intergenische Regionen transkriptionell gekoppelt sind, wobei die intergenische Region oder intergenischen Regionen ausgewählt ist aus der Gruppe, bestehend aus:

(a) Sequenzen, umfassend oder bestehend aus einer der SEQ ID NOs: 1-13;

(b) Sequenzen, die eine Fehlpaarung oder eine Deletion oder Insertion eines Nukleotids zeigen vs. SEQ ID NO: 1, SEQ ID NO: 2 oder SEQ ID NO: 8;

(c) Sequenzen, die eine, zwei oder drei Fehlpaarungen oder eine Deletion oder Insertion von einem, zwei oder drei Nukleotiden zeigen vs. SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 9 oder SEQ ID NO: 10; oder

(d) Sequenzen, die eine, zwei, drei oder vier Fehlpaarungen oder eine Deletion oder Insertion von einem, zwei, drei oder vier Nukleotiden zeigen vs. SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 11, SEQ ID NO: 12 oder SEQ ID NO: 13.


 
10. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 8, wobei die intergenische Region oder die intergenischen Regionen für das grampositive Bakterium endogen ist.
 
11. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 10, wobei die intergenische Region ausgewählt ist aus einer der SEQ ID NOs: 1-13.
 
12. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 11, wobei die intergenische Region die Sequenz von SEQ ID NO: 3 oder SEQ ID NO: 9 umfasst.
 
13. Grampositives Bakterium nach einem der Ansprüche 1, 3 oder 5-12 oder die rekombinante Nukleinsäure nach einem der Ansprüche 2, 3, 5, 6 oder 9-12, wobei das eine oder die mehreren exogenen Gene für ein Produkt kodiert, wobei das Produkt ein Protein, Polypeptid und/oder Peptid ist.
 
14. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 13, wobei das eine oder die mehreren exogenen Gene translational an eine Nukleinsäuresequenz gekoppelt sind, die für ein Sekretionssignal kodiert.
 
15. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 14, wobei das Sekretionssignal ein Lactococcus-Usp45-Sekretionssignal ist.
 
16. Grampositives Bakterium oder die rekombinante Nukleinsäure nach einem der Ansprüche 13-15, wobei das Protein, Polypeptid und/oder Peptid eine therapeutische oder präventive Wirkung in einem Subjekt aufweist.
 
17. Grampositives Bakterium nach einem der Ansprüche 1, 3 oder 5-12 oder die rekombinante Nukleinsäure nach einem der Ansprüche 2, 3, 5, 6 oder 9-12, wobei das eine oder die mehreren exogenen Gene für ein Produkt kodiert, wobei das Produkt ein Antigen zum Induzieren von Immunität oder Immuntoleranz, ein nicht-vaccinogenes therapeutisch aktives Polypeptid, ein Antikörper oder ein funktionelles Fragment davon wie Fab, ein Fusionsprotein oder ein multimeres Protein ist.
 
18. Grampositives Bakterium oder die rekombinante Nukleinsäure nach einem der Ansprüche 13-17, wobei das Protein, Polypeptid und/oder Peptid ausgewählt ist aus der Gruppe, bestehend aus:

(i) Interleukin-10 (IL-10);

(ii) Kleeblattfaktor 1 (TFF1);

(iii) Pro-Insulin (ins); und

(iv) Interleukin-27 (IL-27).


 
19. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 17, wobei das eine oder die mehreren exogenen Gene für einen Einzeldomänenantikörper kodieren.
 
20. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 17, wobei das eine oder die mehreren exogenen Gene für einen Anti-TNFa-Antikörper, vorzugsweise ein Anti-TNFa-Antikörperfragment, mehr bevorzugt eine variable Domäne eines einzelnen Anti-TNFa-Antikörpers kodieren.
 
21. Grampositives Bakterium oder die rekombinante Nukleinsäure nach einem der Ansprüche 1, 2, 19 oder 20, wobei ein exogenes Gen für die leichte Kette (VL) eines Antikörpers oder eines funktionellen Fragments davon kodiert und ein anderes exogenes Gen für die schwere Kette (VH) des Antikörpers oder eines funktionellen Fragments davon kodiert, mehr bevorzugt wobei das funktionelle Fragment Fab ist.
 
22. Grampositives Bakterium oder rekombinante Nukleinsäure nach Anspruch 21, wobei das exogene Gen, das für VL oder ein funktionelles Fragment davon kodiert, transkriptionell an das 3'-Ende des exogenen Gens, das für VH oder ein funktionelles Fragment davon kodiert, gekoppelt ist.
 
23. Grampositives Bakterium oder die rekombinante Nukleinsäure nach einem der Ansprüche 13-22 zur Verwendung als ein Medikament, vorzugsweise zur Verwendung bei Verabreichung oder Abgabe des Produkts an ein Subjekt.
 
24. Grampositives Bakterium oder die rekombinante Nukleinsäure für die Verwendung nach Anspruch 23, wobei das therapeutische Polypeptid an einen Menschen oder ein Tier abgegeben wird, und wobei:

(a) die Erkrankung eine entzündliche Darmerkrankung ist, vorzugsweise Morbus Crohn oder Colitis ulcerosa;

(b) die Erkrankung eine Autoimmunerkrankung ist, vorzugsweise Psoriasis, rheumatoide Arthritis oder Lupus erythematodes;

(c) die Erkrankung eine allergische Erkrankung ist, vorzugsweise Asthma oder eine Nahrungsmittelallergie;

(d) die Erkrankung Zöliakie ist;

(e) die Erkrankung eine neurologische Störung ist, vorzugsweise Morbus Alzheimer, Morbus Parkinson oder amyotrophe Lateralsklerose;

(f) die Erkrankung Krebs ist;

(g) die Erkrankung Osteoporose ist;

(h) die Erkrankung Diabetes ist;

(i) die Erkrankung kardiovaskuläre Erkrankung ist;

(j) die Erkrankung Atherosklerose ist;

(k) die Erkrankung Hämophilie ist;

(l) die Erkrankung eine degenerative Lebererkrankung ist;

(m) die Erkrankung eine Lungenerkrankung ist, vorzugsweise zystische Fibrose;

(n) die Erkrankung Fettleibigkeit ist;

(o) die Erkrankung eine Pathogeninfektion ist, vorzugsweise eine virale oder bakterielle Infektion; oder

(p) die Erkrankung eine Infektionserkrankung ist, vorzugsweise Clostridium dificileassoziierte Erkrankung (CDAD).


 
25. Grampositives Bakterium oder die rekombinante Nukleinsäure für die Verwendung nach Anspruch 24, wobei:

(a) die Erkrankung eine entzündliche Darmerkrankung ist, vorzugsweise Morbus Crohn oder Colitis ulcerosa, und das eine oder die mehreren exogenen Gene für IL-1ra, IL-10, IL-27 oder Kleeblattpeptide kodiert;

(b) die Erkrankung eine Autoimmunerkrankung ist, vorzugsweise Psoriasis, rheumatoide Arthritis oder Lupus erythematodes, und das eine oder die mehreren exogene Gene für IL-1ra, IL-27, IL-10 oder das relevante Autoantigen kodiert;

(c) die Erkrankung eine allergische Erkrankung ist, vorzugsweise Asthma oder eine Nahrungsmittelallergie, und das eine oder die mehreren exogenen Gene für das relevante Allergen kodiert;

(d) die Erkrankung Zöliakie ist, und das eine oder die mehreren exogene Gene für Glutenallergene kodiert;

(e) die Erkrankung eine neurologische Störung ist, einschließlich vorzugsweise Morbus Alzheimer, Morbus Parkinson oder amyotrophe Lateralsklerose, und das eine oder die mehreren exogenen Gene für gehirnstämmigen neurotropen Faktor oder ziliären neurotropen Faktor kodiert;

(f) die Erkrankung Krebs ist, und das eine oder die mehreren exogenen Gene für IL-1, koloniestimulierende Faktoren oder Interferon-W kodiert;

(g) die Erkrankung Osteoporose ist, und das eine oder die mehreren exogenen Gene für transformierenden Wachstumsfaktor f3 kodiert;

(h) die Erkrankung Diabetes ist, und das eine oder die mehreren exogenen Gene für Insulin kodiert;

(i) die Erkrankung kardiovaskuläre Erkrankung ist, und das eine oder die mehreren exogenen Gene für Gewebeplasminogenaktivator kodiert;

(j) die Erkrankung Atherosklerose ist, und das eine oder die mehreren exogenen Gene für Cytokine und/oder Cytokinantagonisten kodiert;

(k) die Erkrankung Hämophilie ist, und das eine oder die mehreren exogenen Gene für Gerinnungsfaktoren kodiert;

(l) die Erkrankung degenerative Lebererkrankung ist, und das eine oder die mehreren exogenen Gene für Hepatozytenwachstumsfaktor oder Interferon-a kodiert;

(m) die Erkrankung eine Lungenerkrankung ist, vorzugsweise zystische Fibrose, und das eine oder die mehreren exogenen Gene für Alpha-Antitrypsin kodiert; oder

(n) die Erkrankung eine Infektionserkrankung ist, vorzugsweise Clostridium dificileassoziierte Erkrankung (CDAD), und das eine oder die mehreren exogenen Gene für einen toxinneutralisierenden Antikörper kodiert.


 
26. Grampositives Bakterium nach einem der Ansprüche 1, 3 oder 5-22 oder die rekombinante Nukleinsäure nach einem der Ansprüche 2, 3, 5, 6 oder 9-22, wobei das grampositive Bakterium ein Milchsäurebakterium ist.
 
27. Grampositives Bakterium oder die rekombinante Nukleinsäure nach Anspruch 26, wobei das Milchsäurebakterium Lactococcus, Lactobacillus oder Enterococcus , vorzugsweise Lactococcus lactis oder Enterococcus faecium, oder wobei das grampositive Bakterium ein Bifidobacterium ist.
 
28. Pharmazeutische Zusammensetzung, umfassend das grampositive Bakterium nach einem der Ansprüche 1, 3, 5-22, 26 oder 27 und einen pharmazeutisch verträglichen Träger.
 
29. Pharmazeutische Zusammensetzung nach Anspruch 28 zur Verwendung als ein Medikament, vorzugsweise zur Verwendung bei Verabreichung oder Abgabe des durch das eine oder die mehreren exogenen Gene kodierten Produkts an ein Subjekt.
 
30. Verwendung des grampositiven Bakteriums oder der rekombinanten Nukleinsäure nach einem der Ansprüche 9 bis 12 zur polycistronischen Expression eines oder mehrerer Gene, offener Leserahmen oder für das grampositive Bakterium exogene kodierender Sequenzen, und eines oder mehrere Gene, offenen Leserahmens oder für das grampositive Bakterium endogene kodierender Sequenzen.
 
31. Verfahren zum Bewirken polycistronischer Expression von dem einen oder den mehreren exogenen Genen oder zum Bewirken polycistronischer Expression von dem einen oder den mehreren endogenen Genen und einem oder mehreren exogenen Genen in einem grampositiven Bakterium, umfassend den Schritt des Einbringens der rekombinanten Nukleinsäure nach Anspruch 2 oder des Vektors nach Anspruch 4 in das grampositive Bakterium.
 
32. Verfahren zum Erzeugen eines grampositiven Bakteriums, das in der Lage ist, ein oder mehrere exogene Proteine zu exprimieren, umfassend den Schritt des Einbringens der rekombinanten Nukleinsäure nach Anspruch 2 oder des Vektors nach Anspruch 4 in das grampositive Bakterium, um in eine polycistronische mRNA transkribiert zu werden.
 
33. Grampositives Bakterium, umfassend eine polycistronische Expressionseinheit, wobei die polycistronische Expressionseinheit in Reihenfolge 5' bis 3' umfasst:

(i) den gapB-Promotor, der für das grampositive Bakterium endogen ist;

(ii) das gapB-Gen, das für das grampositive Bakterium endogen ist; und

(iii) das exogene menschliche Kleeblattfaktor Gen, gekoppelt an das Lactococcus-Usp45-Sekretionssignal (SS:TFF1),

wobei das gapB-Gens transkriptionell an SS:TFF1 gekoppelt ist über die rpmD vorstehenden intergenische Region in dem grampositiven Bakterium, wobei die rpmD vorstehende intergenische Region die Sequenz umfasst von SEQ ID NO: 3 oder SEQ ID NO: 9.
 
34. Grampositives Bakterium, umfassend eine polycistronische Expressionseinheit, wobei die polycistronische Expressionseinheit in Reihenfolge 5' bis 3' umfasst:

(i) den usp45-Promotor, der für das grampositive Bakterium endogen ist;

(ii) das usp45-Gen, das für das grampositive Bakterium endogen ist; und

(iii) das exogene menschliche Kleeblattfaktor Gen, gekoppelt an das Lactococcus-Usp45-Sekretionssignal (SS:ins),

wobei das usp45-Gen transkriptionell an SS:ins gekoppelt ist über die rpmD vorstehende intergenische Region in dem grampositiven Bakterium, wobei die rpmD vorstehende intergenische Region die Sequenz umfasst von SEQ ID NO: 3 oder SEQ ID NO: 9.
 
35. Grampositives Bakterium, umfassend eine polycistronische Expressionseinheit, wobei die polycistronische Expressionseinheit in Reihenfolge 5' bis 3' umfasst:

(i) den enoA-Promotor, der für das grampositive Bakterium endogen ist;

(ii) das enoA-Gen, das für das grampositive Bakterium endogen ist; und

(iii) das exogene menschliche Kleeblattfaktor Gen, gekoppelt an das Lactococcus-Usp45-Sekretionssignal (SS:ins),

wobei das usp45-Gen transkriptionell an SS:ins gekoppelt ist über die rpmD vorstehende intergenische Region in dem grampositiven Bakterium, wobei die rpmD vorstehende intergenische Region die Sequenz umfasst von SEQ ID NO: 3 oder SEQ ID NO: 9.
 
36. Grampositives Bakterium nach einem der Ansprüche 33-35, wobei die polycistronische Expressionseinheit an dem für den Promotor endogenen Locus lokalisiert ist.
 


Revendications

1. Bactérie à Gram positif comprenant une unité d'expression polycistronique, ladite unité d'expression polycistronique comprenant un gène endogène et un ou plusieurs gènes exogènes, dans laquelle ledit gène endogène et ledit ou lesdits gènes exogènes sont commandés de façon transcriptionnelle par un promoteur endogène à la bactérie à Gram positif, dans laquelle ledit promoteur est

(i) un promoteur de gène ribosomique choisi dans le groupe constitué de :

(a) un promoteur de rpmD,

(b) un promoteur de rpsD,

(c) un promoteur de rpsL,

(d) un promoteur de rpsG,

(e) un promoteur de rplR,

(f) un promoteur de rpsE,

(g) un promoteur de rpsK,

(h) un promoteur de rplJ,

(i) un promoteur de rplL,

(j) un promoteur de rpsB,

(k) un promoteur de rplD,

(l) un promoteur de rplW,

(m) un promoteur de rplB,

(n) un promoteur de rplO,

(o) un promoteur de rplK,

(p) un promoteur de rpsH,

(q) un promoteur de rpsM,

(r) un promoteur de rpsS,

(s) un promoteur de rplU,

(t) un promoteur de rplV,

(u) un promoteur de rplP

(v) un promoteur de rplN,

(w) un promoteur de rpsJ,

(x) un promoteur de rplX,

(y) un promoteur de rplE,

(z) un promoteur de rplF, et

(aa) un promoteur de rplM ;

(ii) un promoteur de promoteur de gène de glycolyse choisi dans le groupe constitué de :

(a) un promoteur de fbaA, et

(b) un promoteur de pgk ; ou

(iii) un promoteur de dpsA

de ladite bactérie à Gram positif.
 
2. Acide nucléique recombiné comprenant une unité d'expression polycistronique, ladite unité d'expression polycistronique comprenant un gène endogène à une bactérie à Gram positif et un ou plusieurs gènes exogènes à la bactérie à Gram positif, dans lequel ledit gène endogène et ledit ou lesdits gènes exogènes sont commandés de façon transcriptionnelle par un promoteur endogène à la bactérie à Gram positif, dans lequel ledit promoteur est

(i) un promoteur de gène ribosomique choisi dans le groupe constitué de :

(a) un promoteur de rpmD,

(b) un promoteur de rpsD,

(c) un promoteur de rpsL,

(d) un promoteur de rpsG,

(e) un promoteur de rplR,

(f) un promoteur de rpsE,

(g) un promoteur de rpsK,

(h) un promoteur de rplJ,

(i) un promoteur de rplL,

(j) un promoteur de rpsB,

(k) un promoteur de rplD,

(l) un promoteur de rplW,

(m) un promoteur de rplB,

(n) un promoteur de rplO,

(o) un promoteur de rplK,

(p) un promoteur de rpsH,

(q) un promoteur de rpsM,

(r) un promoteur de rpsS,

(s) un promoteur de rplU,

(t) un promoteur de rplV,

(u) un promoteur de rplP

(v) un promoteur de rplN,

(w) un promoteur de rpsJ,

(x) un promoteur de rplX,

(y) un promoteur de rplE,

(z) un promoteur de rplF, et

(aa) un promoteur de rplM ;

(ii) un promoteur de promoteur de gène de glycolyse choisi dans le groupe constitué de :

(a) un promoteur de fbaA, et

(b) un promoteur de pgk ; ou

(iii) un promoteur de dpsA

de ladite bactérie à Gram positif.
 
3. Bactérie à Gram positif selon la revendication 1 ou acide nucléique recombiné selon la revendication 2, dans lequel ledit promoteur est un promoteur de rpmD.
 
4. Vecteur comprenant l'acide nucléique recombiné selon les revendications 2 ou 3.
 
5. Bactérie à Gram positif selon la revendication 1 ou acide nucléique recombiné selon la revendication 2, dans lequel ledit ou lesdits gènes exogènes sont couplés de façon transcriptionnelle à l'extrémité 3' dudit gène endogène.
 
6. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 4, dans lequel un desdits gènes exogènes est le gène le plus 3' de l'unité d'expression polycistronique.
 
7. Bactérie à Gram positif selon les revendications 1 ou 3, dans laquelle le gène endogène est situé dans son locus chromosomique natif dans la bactérie à Gram positif.
 
8. Bactérie à Gram positif selon la revendication 7, dans laquelle le gène endogène est couplé de façon transcriptionnelle au gène exogène ou aux gènes exogènes par intégration chromosomique du ou des gènes exogènes dans ledit locus, de préférence par intégration chromosomique du ou des gènes exogènes 3' du gène endogène dans ledit locus.
 
9. Bactérie à Gram positif selon l'une quelconque des revendications 1, 3 ou 5 à 8, ou acide nucléique recombiné selon l'une quelconque des revendications 2, 3, 5 ou 6, dans lequel ledit gène endogène et ledit ou lesdits gènes exogènes sont couplés de façon transcriptionnelle par une région intergénique ou des régions intergéniques actives dans la bactérie à Gram positif, dans lequel ladite région intergénique ou lesdites régions intergéniques sont choisies dans le groupe constitué de :

(a) séquences comprenant ou constitués de l'une quelconque des SEQ ID NO : 1 à 13 ;

(b) séquences présentant une non-correspondance ou une délétion ou insertion d'un nucléotide par rapport à SEQ ID NO: 1, SEQ ID NO: 2 ou SEQ ID No. : 8 ;

(c) séquences présentant une, deux ou trois non-correspondances, ou une délétion ou insertion d'un, deux ou trois nucléotides par rapport à SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 9 ou SEQ ID NO: 10 ; ou

(d) séquences présentant une, deux, trois ou quatre non-correspondances ou une délétion ou insertion d'un, deux, trois ou quatre nucléotides par rapport à SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 11, SEQ ID No. : 12 ou SEQ ID No. : 13.


 
10. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 8, dans lequel la région intergénique ou les régions intergéniques sont endogènes à ladite bactérie à Gram positif.
 
11. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 10, dans lequel ladite région intergénique est choisie parmi l'une quelconque des SEQ ID NO : 1 à 13.
 
12. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 11, dans lequel ladite région intergénique comprend la séquence de SEQ ID NO: 3 ou SEQ ID NO: 9.
 
13. Bactérie à Gram positif selon l'une quelconque des revendications 1, 3 ou 5 à 12 ou acide nucléique recombiné selon l'une quelconque des revendications 2, 3, 5, 6 ou 9 à 12, dans lequel ledit ou lesdits gènes exogènes codent pour un produit, lequel produit est une protéine, un polypeptide et/ou un peptide.
 
14. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 13, dans lequel ledit ou lesdits gènes exogènes sont couplés par traduction à une séquence d'acides nucléiques codant pour un signal de sécrétion.
 
15. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 14, dans lequel ledit signal de sécrétion est un signal de sécrétion Usp45 de Lactococcus.
 
16. Bactérie à Gram positif ou acide nucléique recombiné selon l'une quelconque des revendications 13 à 15, dans lequel ladite protéine, ledit polypeptide et/ou ledit peptide ont un effet thérapeutique ou prophylactique chez un sujet.
 
17. Bactérie à Gram positif selon l'une quelconque des revendications 1, 3 ou 5 à 12 ou acide nucléique recombiné selon l'une quelconque des revendications 2, 3, 5, 6 ou 9 à 12, dans lequel ledit ou lesdits gènes exogènes codent pour un produit, lequel produit est un antigène pour induire une immunité ou une immunotolérance, un polypeptide thérapeutiquement actif non vaccinogène, un anticorps ou un fragment fonctionnel de celui-ci tel que Fab, une protéine hybride ou une protéine multimère.
 
18. Bactérie à Gram positif ou acide nucléique recombiné selon l'une quelconque des revendications 13 à 17, dans lequel ladite protéine, ledit polypeptide et/ou ledit peptide est choisi dans le groupe constitué de :

(i) interleukine-10 (IL-10) ;

(ii) facteur en trèfle 1 (TFF1) ;

(iii) pro-insuline (ins) ; et

(iv) interleukine-27 (IL-27).


 
19. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 17, dans lequel ledit ou lesdits gènes exogènes codent pour un anticorps à domaine unique.
 
20. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 17, dans lequel ledit ou lesdits gènes exogènes codent pour un anticorps anti-TNFa, de préférence un fragment d'anticorps anti-TNFa, mieux encore un domaine variable d'anticorps unique anti-TNFα.
 
21. Bactérie à Gram positif ou acide nucléique recombiné selon l'une quelconque des revendications 1, 2, 19 ou 20, dans lequel un gène exogène code pour la chaîne légère (VL) d'un anticorps ou d'un fragment fonctionnel de celui-ci, et un autre gène exogène code pour la chaîne lourde (VH) de l'anticorps ou d'un fragment fonctionnel de celui-ci, plus préférablement dans lequel le fragment fonctionnel est Fab.
 
22. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 21, dans lequel le gène exogène codant pour VL ou un fragment fonctionnel de celui-ci est couplé de façon transcriptionnelle à l'extrémité 3' du gène exogène codant pour VH ou un fragment fonctionnel de celle-ci.
 
23. Bactérie à Gram positif ou acide nucléique recombiné selon l'une quelconque des revendications 13 à 22, pour une utilisation en tant que médicament, de préférence pour une utilisation dans l'administration ou la distribution dudit produit à un sujet.
 
24. Bactérie à Gram positif ou acide nucléique recombiné pour l'utilisation selon la revendication 23, dans lequel le polypeptide thérapeutique est distribué à un humain ou un animal, et dans lequel :

(a) la maladie est une maladie intestinale inflammatoire, de préférence la maladie de Crohn ou la colite ulcéreuse ;

(b) la maladie est une maladie auto-immune, de préférence le psoriasis, la polyarthrite rhumatoïde ou le lupus érythémateux ;

(c) la maladie est une maladie allergique, de préférence de l'asthme ou une allergie alimentaire ;

(d) la maladie est une maladie cœliaque ;

(e) la maladie est un trouble neurologique, de préférence la maladie d'Alzheimer, la maladie de Parkinson ou la sclérose latérale amyotrophique ;

(f) la maladie est le cancer ;

(g) la maladie est l'ostéoporose ;

(h) la maladie est le diabète ;

(i) la maladie est une maladie cardiovasculaire ;

(j) la maladie est l'athérosclérose ;

(k) la maladie est l'hémophilie ;

(l) la maladie est un trouble hépatique dégénératif ;

(m) la maladie est une maladie pulmonaire, de préférence la mucoviscidose ;

(n) la maladie est l'obésité ;

(o) la maladie est une infection par un agent pathogène, de préférence une infection virale ou bactérienne ; ou

(p) la maladie est une maladie infectieuse, de préférence une maladie associée à Clostridium dificile (CDAD).


 
25. Bactérie à Gram positif ou acide nucléique recombiné pour l'utilisation selon la revendication 24, dans lequel :

(a) la maladie est une maladie intestinale inflammatoire, de préférence la maladie de Crohn ou la colite ulcéreuse, et ledit ou lesdits gènes exogènes codent pour IL-1ra, IL-10, IL-27 ou des peptides en trèfle ;

(b) la maladie est une maladie auto-immune, de préférence le psoriasis, la polyarthrite rhumatoïde ou le lupus érythémateux, et ledit ou lesdits gènes exogènes codent pour IL-1ra, IL-27, IL-10 ou l'auto-antigène pertinent ;

(c) la maladie est une maladie allergique, de préférence l'asthme ou une allergie alimentaire, et ledit ou lesdits gènes exogènes codent pour l'allergène pertinent ;

(d) la maladie est une maladie cœliaque, et ledit ou lesdits gènes exogènes codent pour des allergènes de gluten ;

(e) la maladie est un trouble neurologique comprenant, de préférence, la maladie d'Alzheimer, la maladie de Parkinson ou la sclérose latérale amyotrophique, et ledit ou lesdits gènes exogènes codent pour le facteur neurotrope dérivé du cerveau ou le facteur neurotrope ciliaire ;

(f) la maladie est un cancer, et ledit ou lesdits gènes exogènes codent pour IL-1, des facteurs de stimulation des colonies ou l'interféron W ;

(g) la maladie est l'ostéoporose, et ledit ou lesdits gènes exogènes codent pour le facteur de croissance transformant f3 ;

(h) la maladie est le diabète, et ledit ou lesdits gènes exogènes codent pour l'insuline ;

(i) la maladie est une maladie cardiovasculaire, et ledit ou lesdits gènes exogènes codent pour un activateur tissulaire du plasminogène ;

(j) la maladie est l'athérosclérose, et ledit ou lesdits gènes exogènes codent pour des cytokines et/ou des antagonistes de cytokines ;

(k) la maladie est l'hémophilie, et ledit ou lesdits gènes exogènes codent pour des facteurs de coagulation ;

(l) la maladie est une maladie dégénérative du foie, et ledit ou lesdits gènes exogènes codent pour le facteur de croissance hépatocytaire ou l'interféron a ;

(m) la maladie est une maladie pulmonaire, de préférence la mucoviscidose, et ledit ou lesdits gènes exogènes codent pour l'alpha-antitrypsine ; ou

(n) la maladie est une maladie infectieuse, de préférence une maladie associée à Clostridium dificile (CDAD), et ledit ou lesdits gènes exogènes codent pour un anticorps de neutralisation de toxine.


 
26. Bactérie à Gram positif selon l'une quelconque des revendications 1, 3 ou 5 à 22 ou acide nucléique recombiné selon l'une quelconque des revendications 2, 3, 5, 6 ou 9 à 22, dans lequel la bactérie à Gram positif est une bactérie d'acide lactique.
 
27. Bactérie à Gram positif ou acide nucléique recombiné selon la revendication 26, dans lequel la bactérie d'acide lactique est Lactococcus, Lactobacillus, ou Enterococcus, de préférence Lactococcus lactis ou Enterococcus faecium, ou dans laquelle la bactérie à Gram positif est une Bifidobacterium.
 
28. Composition pharmaceutique comprenant la bactérie à Gram positif selon l'une quelconque des revendications 1, 3, 5 à 22, 26 ou 27, et un véhicule acceptable sur le plan pharmaceutique.
 
29. Composition pharmaceutique selon la revendication 28 pour une utilisation en tant que médicament, de préférence pour une utilisation dans l'administration ou la distribution du produit codé par ledit ou lesdits gènes exogènes à un sujet.
 
30. Utilisation de la bactérie à Gram positif ou de l'acide nucléique recombiné selon l'une quelconque des revendications 9 à 12, pour une expression polycistronique d'un ou plusieurs gènes, cadres de lecture ouverts ou séquences codantes exogènes à ladite bactérie à Gram positif et un ou plusieurs gènes, cadre de lecture ouvert ou séquences codantes endogènes à ladite bactérie à Gram positif.
 
31. Procédé pour effectuer une expression polycistronique du ou des gènes exogènes ou pour effectuer une expression polycistronique du ou des gènes endogènes et d'un ou plusieurs gènes exogènes dans une bactérie à Gram positif, comprenant l'étape consistant à introduire l'acide nucléique recombiné selon la revendication 2 ou le vecteur selon la revendication 4, dans ladite bactérie à Gram positif.
 
32. Procédé pour générer une bactérie à Gram positif capable d'exprimer une ou plusieurs protéines exogènes, comprenant l'étape consistant à introduire l'acide nucléique recombiné selon la revendication 2 ou le vecteur selon la revendication 4 dans ladite bactérie à Gram positif de façon à ce être transcrit dans un ARNm polycistronique.
 
33. Bactérie à Gram positif comprenant une unité d'expression polycistronique, ladite unité d'expression polycistronique comprenant, dans l'ordre de 5' à 3' :

(i) le promoteur de gapB endogène à ladite bactérie à Gram positif ;

(ii) le gène gapB endogène à ladite bactérie à Gram positif ; et

(iii) le facteur en trèfle humain de gène exogène couplé au signal de sécrétion Usp45 de Lactococcus (SS:TFF1),

dans lequel le gène gapB est couplé de façon transcriptionnelle au SS:TFF1 par l'intermédiaire de la région intergénique précédant rpmD dans ladite bactérie à Gram positif, dans lequel la région intergénique précédant rpmD comprend la séquence de SEQ ID NO: 3 ou SEQ ID NO: 9.
 
34. Bactérie à Gram positif comprenant une unité d'expression polycistronique, ladite unité d'expression polycistronique comprenant, dans l'ordre de 5' à 3' :

(i) le promoteur d'usp45 endogène à ladite bactérie à Gram positif ;

(ii) le gène usp45 endogène à ladite bactérie à Gram positif ; et

(iii) le facteur en trèfle humain de gène exogène couplé au signal de sécrétion Usp45 de Lactococcus (SS:ins),

dans lequel le gène usp45 est couplé de façon transcriptionnelle au SS:ins par l'intermédiaire de la région intergénique précédant rpmD dans ladite bactérie à Gram positif, dans lequel la région intergénique précédant rpmD comprend la séquence de SEQ ID NO: 3 ou SEQ ID NO: 9.
 
35. Bactérie à Gram positif comprenant une unité d'expression polycistronique, ladite unité d'expression polycistronique comprenant, dans l'ordre de 5' à 3' :

(i) le promoteur d'enoA endogène à ladite bactérie à Gram positif ;

(ii) le gène enoA endogène à ladite bactérie à Gram positif ; et

(iii) le facteur en trèfle humain de gène exogène couplé au signal de sécrétion Usp45 de Lactococcus (SS:ins),

dans lequel le gène usp45 est couplé de façon transcriptionnelle au SS:ins par l'intermédiaire de la région intergénique précédant rpmD dans ladite bactérie à Gram positif, dans lequel la région intergénique précédant rpmD comprend la séquence de SEQ ID NO: 3 ou SEQ ID NO: 9.
 
36. Bactérie à Gram positif selon l'une quelconque des revendications 33 à 35, dans laquelle ladite unité d'expression polycistronique se situe au niveau du locus endogène au promoteur.
 




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Cited references

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Patent documents cited in the description




Non-patent literature cited in the description