(19)
(11)EP 3 653 638 A1

(12)EUROPEAN PATENT APPLICATION
published in accordance with Art. 153(4) EPC

(43)Date of publication:
20.05.2020 Bulletin 2020/21

(21)Application number: 18832785.2

(22)Date of filing:  13.07.2018
(51)Int. Cl.: 
C07K 14/025  (2006.01)
C12P 21/02  (2006.01)
A61P 17/12  (2006.01)
C12N 15/37  (2006.01)
A61K 39/12  (2006.01)
(86)International application number:
PCT/CN2018/095632
(87)International publication number:
WO 2019/011331 (17.01.2019 Gazette  2019/03)
(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
Designated Extension States:
BA ME
Designated Validation States:
KH MA MD TN

(30)Priority: 14.07.2017 CN 201710573731

(71)Applicants:
  • Xiamen University
    Xiamen, Fujian 361005 (CN)
  • Xiamen Innovax Biotech Co., Ltd.
    Xiamen, Fujian 361022 (CN)

(72)Inventors:
  • GU, Ying
    Xiamen Fujian 361005 (CN)
  • LI, Shaowei
    Xiamen Fujian 361005 (CN)
  • SONG, Shuo
    Xiamen Fujian 361005 (CN)
  • HE, Maozhou
    Xiamen Fujian 361005 (CN)
  • LI, Zhihai
    Xiamen Fujian 361005 (CN)
  • XIA, Ningshao
    Xiamen Fujian 361005 (CN)

(74)Representative: Lavoix 
Bayerstrasse 83
80335 München
80335 München (DE)

  


(54)MUTANT OF L1 PROTEIN OF HUMAN PAPILLOMAVIRUS TYPE 16


(57) Provided are a mutated HPV16 L1 protein (or a variant thereof), a sequence encoding the same and a method for preparing the same, as well as a virus-like particle comprising the same. The protein (or variant thereof) and the virus-like particle are capable of inducing neutralizing antibodies against at least two types of HPV (e.g., HPV16 and HPV35, or HPV16, HPV35, and HPV31), and therefore can be used to prevent infection by said at least two HPV types, and a disease caused by said infection, such as cervical cancer and condyloma acuminatum. Also provided are a use of the above protein and virus-like particle in the manufacture of a pharmaceutical composition or vaccine for preventing infection by said at least two HPV types, and a disease caused by said infection, such as cervical cancer and condyloma acuminatum.




Description

Technical Field



[0001] The invention relates to the fields of molecular virology and immunology. In particular, the present invention relates to a mutated HPV16 L1 protein (or a variant thereof), a sequence encoding the same, a method for preparing the same, as well as a virus-like particle comprising the same, in which the protein (or variant thereof) and the virus-like particle are capable of inducing a neutralizing antibody against at least two types of HPV (e.g., HPV 16 and HPV 35; or HPV 16, HPV 35 and HPV 31), and therefore can be used to prevent infection by said at least two HPV types, and a disease caused by said infection, such as cervical cancer and condyloma acuminatum. The invention further relates to a use of the above-mentioned protein and virus-like particle in the manufacture of a pharmaceutical composition or a vaccine for preventing infection by said at least two HPV types, and a disease caused by said infection, such as cervical cancer and condyloma acuminatum.

Background Art



[0002] Human papillomavirus (HPV) mainly causes warts in skin and mucosa. According to its relationship with tumorigenesis, HPV can be divided into high-risk type and low-risk type, among which infection by high-risk HPV types is confirmed to be the main cause of genital cancers including cervical cancers in women; while infection by low-risk HPV type mainly causes condyloma acuminatum. The most effective way to prevent and control the HPV infections is to administer a HPV vaccine, especially a vaccine against high-risk HPV types capable of causing cervical cancer.

[0003] The major capsid protein L1 of HPV has the characteristics of self-assembly into hollow Virus-Like Particle (VLP). The HPV VLP has a symmetrical icosahedral structure composed of 72 pentamers of the major capsid protein L1 (Doorbar, J. and P. H. Gallimore. 1987. J Virol, 61(9): 2793-9). The structure of HPV VLP is highly similar to that of native HPV, retaining most of the neutralizing epitopes of native virus and being capable of inducing high-titer neutralizing antibodies (Kirnbauer, R., F. Booy, et al. 1992 Proc Natl Acad Sci USA 89(24): 12180-4).

[0004] However, existing studies have shown that HPV VLP mainly induces neutralizing antibodies against the same HPV type, produces protective immunity against the same HPV type, and only has low cross-protective effect among a few highly homologous types (Sara L. Bissett, Giada Mattiuzzo, et al. 2014 Vaccine. 32:6548-6555). Therefore, the scope of protection of existing HPV vaccines is very limited. In general, VLP of one HPV type can only be used to prevent infection by the same HPV type. In this case, if it needs to expand the scope of protection of HPV vaccines, the only way is to add VLPs of more HPV types in vaccines. Currently available HPV vaccines include Merck's Gardasil® (which is a quadrivalent vaccine against HPV 16, 18, 6 and 11), GSK's Cervarix® (which is a bivalent vaccine against HPV 16, 18) and Merck's Gardasil® 9 (which is a nine-valent vaccine), which are all made by mixing VLPs of multiple types of HPV. However, this approach will result in a significant cost increase in production of HPV vaccines and may lead to potential safety issues due to the increased immunization doses.

[0005] Therefore, there is a need in the art to develop HPV virus-like particles capable of inducing protective neutralizing antibodies against multiple types of HPV, so as to more economically and effectively prevent infection by multiple HPV types and the diseases caused thereby such as cervical cancer and condyloma acuminatum.

Contents of the Invention



[0006] The present invention is based, at least in part, on the inventors' unexpected discovery that after replacing a specific segment of L1 protein of Human Papillomavirus (HPV) type 16 with the corresponding segment of L1 protein of a second type of HPV (such as HPV35), the obtained mutated HPV16 L1 protein can induce the generation of high-titer neutralizing antibodies against HPV16 and the second type of HPV (such as HPV35) in the body with a protective effect comparable to that of a mixture of HPV16 VLP and VLP of the second type of HPV; moreover, the protective effect thereof against HPV16 is comparable to that of the HPV 16 VLP alone, and the protective effect thereof against the second-type of HPV (e.g., HPV 35) is comparable to that of VLP of the second-type of HPV alone.

[0007] In addition, based on the above substitution, another specific segment of the HPV16 L1 protein may be further substituted with a corresponding segment of L1 protein of a third-type of HPV (e.g., HPV31), and the obtained mutated HPV16 L1 protein having double substitutions can induce the generation of high-titer neutralizing antibodies against HPV16, the second type of HPV (such as HPV35) and the third type of HPV (such as HPV31) in the body with a protective effect comparable to that of a mixture of HPV16 VLP, and VLPs of the second type and third type of HPV; moreover, the protective effect thereof against HPV16 is comparable to that of the HPV16 VLP alone, the protective effect thereof against the second-type of HPV (e.g., HPV35) is comparable to that of VLP of the second-type of HPV alone, and the protective effect thereof against the third-type of HPV (e.g., HPV31) is comparable to that of VLP of the third-type of HPV alone.

[0008] Thus, in one aspect, the invention provides a mutated HPV16 L1 protein or a variant thereof, wherein the mutated HPV16 L1 protein has the following mutations compared to a wild-type HPV16 L1 protein:
  1. (1) a N-terminal truncation of 4-50 amino acids, such as 4, 6, 8, 10, 20, 30 or 40 amino acids; and
  2. (2) a substitution of amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a second type of wild-type HPV;
    optionally, the mutated HPV16 L1 protein further has the following mutation:
  3. (3) a substitution of amino acid residues at positions 76-87 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a third type of wild-type HPV;
  4. (4) a substitution of amino acid residues at positions 152-167 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a third type of wild-type HPV; or
  5. (5) a substitution of amino acid residues at positions 202-207 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a third type of wild-type HPV;
    and, the variant differs from the mutated HPV16 L1 protein only by substitution (preferably conservative substitution), addition or deletion of one or several (e.g., 1, 2, 3,4, 5, 6, 7, 8, or 9) amino acids, and maintains the function of the mutated HPV16 L1 protein, i.e., an ability of inducing neutralizing antibodies against at least two types of HPV (e.g., HPV16 and HPV35, or HPV16, HPV35 and HPV31).


[0009] In certain preferred embodiments, the mutated HPV16 L1 protein has a N-terminal truncation of 30 or 40 amino acids compared to the wild-type HPV16 L1 protein.

[0010] In certain preferred embodiments, the mutated HPV16 L1 protein has a N-terminal truncation of 30 amino acids compared to the wild-type HPV16 L1 protein.

[0011] In certain preferred embodiments, the second type of wild-type HPV is HPV35. In certain preferred embodiments, the amino acid residues at the corresponding positions described in (2) are the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein.

[0012] In certain preferred embodiments, the third-type of wild-type HPV is HPV31. In certain preferred embodiments, the amino acid residues at the corresponding positions described in (3) are the amino acid residues at positions 50-62 of the wild-type HPV31 L1 protein. In certain preferred embodiments, the amino acid residues at the corresponding positions described in (4) are the amino acid residues at positions 127-142 of the wild-type HPV31 L1 protein. In certain preferred embodiments, the amino acid residues at the corresponding positions described in (5) are the amino acid residues at positions 177-182 of the wild-type HPV31 L1 protein.

[0013] In certain preferred embodiments, the wild-type HPV 16 L1 protein has an amino acid sequence set forth in SEQ ID NO: 1.

[0014] In certain preferred embodiments, the wild-type HPV35 L1 protein has an amino acid sequence set forth in SEQ ID NO: 2.

[0015] In certain preferred embodiments, the wild-type HPV31 L1 protein has an amino acid sequence set forth in SEQ ID NO: 3.

[0016] In certain preferred embodiments, the sequence of the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein is set forth in SEQ ID NO: 25.

[0017] In certain preferred embodiments, the sequence of amino acid residues at positions 50-62 of the wild-type HPV31 L1 protein is set forth in SEQ ID NO:26.

[0018] In certain preferred embodiments, the sequence of amino acid residues at positions 127-142 of the wild-type HPV31 L1 protein is set forth in SEQ ID NO:27.

[0019] In certain preferred embodiments, the sequence of amino acid residues at positions 177-182 of the wild-type HPV31 L1 protein is set forth in SEQ ID NO: 28.

[0020] In certain preferred embodiments, the mutated HPV16 L1 protein has an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 9, 10, 11.

[0021] In another aspect, the invention provides an isolated nucleic acid encoding the mutated HPV16 L1 protein or variant thereof as described above. In another aspect, the invention provides a vector comprising the isolated nucleic acid. In certain preferred embodiments, the isolated nucleic acid of the invention has a nucleotide sequence selected from the group consisting of SEQ ID NOs: 19, 21, 22, 23.

[0022] Vectors useful for insertion of a polynucleotide of interest are well known in the art and include, but are not limited to, cloning vectors and expression vectors. In one embodiment, the vector is, for example, a plasmid, a cosmid, a phage, and the like.

[0023] In another aspect, the invention also relates to a host cell comprising the isolated nucleic acid or the vector as described above. Such host cells include, but are not limited to, prokaryotic cells such as E. coli cells, and eukaryotic cells such as yeast cells, insect cells, plant cells, and animal cells (e.g., mammalian cells, such as mouse cells, human cells, etc.). The host cell of the invention may also be a cell line, such as a 293T cell.

[0024] In another aspect, the present invention relates to an HPV virus-like particle, in which the virus-like particle comprises the mutated HPV16 L1 protein or a variant thereof of the present invention, or consists of or is formed by the mutated HPV16 L1 protein or a variant thereof of the present invention.

[0025] In certain preferred embodiments, the HPV virus-like particle of the invention comprises a mutated HPV16 L1 protein, which has a N-terminal truncation of 4-50 amino acids, such as 4, 6, 8, 10, 20, 30 or 40 amino acids, compared to the wild-type HPV16 L1 protein, and has a substitution of amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein.

[0026] In certain preferred embodiments, the HPV virus-like particle of the invention comprises a mutated HPV16 L1 protein, which has a N-terminal truncation of 4-50 amino acids, such as 4, 6, 8, 10, 20, 30 or 40 amino acids, compared to the wild-type HPV16 L1 protein, and has a substitution of amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein, and a substitution of amino acid residues at positions 76-87 of the wild-type HPV16 L1 protein with the amino acid residues at positions 50-62 of the wild-type HPV31 L1 protein.

[0027] In certain preferred embodiments, the HPV virus-like particle of the invention comprises a mutated HPV16 L1 protein, which has a N-terminal truncation of 4-50 amino acids, such as 4, 6, 8, 10, 20, 30 or 40 amino acids, compared to the wild-type HPV16 L1 protein, and has a substitution of amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein, and a substitution of amino acid residues at positions 152-167 of the wild-type HPV16 L1 protein with the amino acid residues at positions 127-142 of the wild-type HPV31 L1 protein.

[0028] In certain preferred embodiments, the HPV virus-like particle of the invention comprises a mutated HPV16 L1 protein, which has a N-terminal truncation of 4-50 amino acids, such as 4, 6, 8, 10, 20, 30 or 40 amino acids, compared to the wild-type HPV16 L1 protein, and has a substitution of amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein, and a substitution of amino acid residues at positions 202-207 of the wild-type HPV16 L1 protein with the amino acid residues at positions 177-182 of the wild-type HPV31 L1 protein.

[0029] In a particularly preferred embodiment, the HPV virus-like particle of the invention comprises a mutated HPV16 L1 protein having the sequence set forth in SEQ ID NOs: 7, 9, 10 or 11.

[0030] In another aspect, the invention also relates to a composition comprising the mutated HPV16 L1 protein or a variant thereof, or the isolated nucleic acid or the vector or the host cell or the HPV virus-like particle. In certain preferred embodiments, the composition comprises the mutated HPV16 L1 protein or a variant thereof of the invention. In certain preferred embodiments, the composition comprises the HPV virus-like particle of the invention.

[0031] In another aspect, the invention also relates to a pharmaceutical composition or vaccine comprising the HPV virus-like particle of the invention, optionally further comprising a pharmaceutically acceptable carrier and/or excipient. The pharmaceutical composition or vaccine of the present invention can be used for preventing an HPV infection or a disease caused by an HPV infection such as cervical cancer and condyloma acuminatum.

[0032] In certain preferred embodiments, the HPV virus-like particle is present in an amount effective for preventing HPV infection or a disease caused by HPV infection. In certain preferred embodiments, the HPV infection is infection by one or more HPV types (e.g., HPV 16 infection, HPV 35 infection, and/or HPV 31 infection). In certain preferred embodiments, the disease caused by HPV infection is selected from the group consisting of cervical cancer and condyloma acuminatum.

[0033] The pharmaceutical composition or vaccine of the invention may be administered by a method well known in the art, for example, but not limited to, administration by oral or injection. In the present invention, a particularly preferred mode of administration is injection.

[0034] In certain preferred embodiments, the pharmaceutical composition or vaccine of the invention is administered in a form of a unit dosage. For example, but not intended to limit the invention, the amount of HPV virus-like particle contained in each unit dose is from 5 µg to 80 µg, preferably from 20 µg to 40 µg.

[0035] In another aspect, the present invention relates to a method for preparing the mutated HPV16 L1 protein or variant thereof as described above, which comprises expressing the mutated HPV16 L1 protein or variant thereof in a host cell, and then recovering the mutated HPV16 L1 protein or variant thereof from a culture of the host cell.

[0036] In certain preferred embodiments, the host cell is E. coli.

[0037] In certain preferred embodiments, the method comprises the steps of: expressing the mutated HPV16 L1 protein or variant thereof in E. coli, and then obtaining the mutated HPV16 L1 protein or a variant thereof by purifying a lysate supernatant of the E. coli. In certain preferred embodiments, the mutated HPV16 L1 protein or variant thereof is recovered from the lysate supernatant of the E. coli by chromatography (e.g., cation exchange chromatography, hydroxyapatite chromatography, and/or hydrophobic interaction chromatography).

[0038] In another aspect, the invention relates to a method for preparing a vaccine, comprising combining the HPV virus-like particle of the invention with a pharmaceutically acceptable carrier and/or excipient.

[0039] In another aspect, the present invention relates to a method for preventing HPV infection or a disease caused by HPV infection, comprising administering to a subject a prophylactically effective amount of the HPV virus-like particle or pharmaceutical composition or vaccine according to the present invention. In a preferred embodiment, the HPV infection is infection by one or more HPV types (e.g., HPV 16 infection, HPV 35 infection, and/or HPV 31 infection). In another preferred embodiment, the disease caused by HPV infection includes, but is not limited to, cervical cancer and condyloma acuminatum. In another preferred embodiment, the subject is a mammal, such as a human.

[0040] In another aspect, the invention relates to a use of the mutated HPV16 L1 protein or variant thereof or the HPV virus-like particle according to the present invention in the manufacture of a pharmaceutical composition or a vaccine for the prevention of HPV infection or a disease caused by HPV infection. In a preferred embodiment, the HPV infection is infection by one or more HPV types (e.g., HPV 16 infection, HPV 35 infection, and/or HPV 31 infection). In another preferred embodiment, the disease caused by HPV infection includes, but is not limited to, cervical cancer and condyloma acuminatum.

Description and explanation of related terms in the present invention



[0041] In the present invention, the scientific and technical terms used herein have the meanings commonly understood by those skilled in the art, unless otherwise stated. Moreover, the laboratory procedures of cell culture, molecular genetics, nucleic acid chemistry, and immunology used herein are all routine steps widely used in the corresponding fields. Also, for a better understanding of the present invention, definitions and explanations of related terms are provided below.

[0042] According to the invention, the term "a second type of wild-type HPV" means another type of wild-type HPV that is different from HPV16. In the present invention, the second-type of wild-type HPV is preferably wild-type HPV35. According to the invention, the term "a third-type of wild-type HPV" refers to another type of wild-type HPV that is different from HPV 16 and the second-type of wild-type HPV. In the present invention, the third-type of wild-type HPV is preferably wild-type HPV31.

[0043] According to the invention, the expression "corresponding position" refers to an equivalent position of the sequences being compared when the sequences are optimally aligned, i.e. the sequences are aligned to obtain a highest percentage of identity.

[0044] According to the invention, the term "wild-type HPV16 L1 protein" refers to the major capsid protein L1 naturally present in human papillomavirus type 16 (HPV16). The sequence of the wild-type HPV16 L1 protein is well known in the art and can be found in various public databases (e.g., NCBI database accession numbers ANA05496.1, ANA05539.1, AGC65525.1, AAV91659.1 and AAD33259.1).

[0045] In the present invention, when referring to the amino acid sequence of the wild-type HPV16 L1 protein, it is described with reference to the sequence shown in SEQ ID NO: 1. For example, the expression "amino acid residues at positions 292 to 316 of the wild-type HPV16 L1 protein" refers to the amino acid residues at positions 292 to 316 of the polypeptide as set forth in SEQ ID NO: 1. However, it will be understood by those skilled in the art that the wild-type HPV 16 may include a plurality of isolates, and the various isolates may have differences in the amino acid sequences of their L1 proteins. Further, those skilled in the art would understand that although there might be differences in sequence, the L1 proteins of different isolates of HPV 16 have a very high amino acid sequence identity (usually above 95%, such as above 96%, above 97%, above 98%, or above 99%), and have substantially the same biological function. Therefore, in the present invention, the term "wild-type HPV16 L1 protein" includes not only the protein represented by SEQ ID NO: 1, but also the L1 proteins of various HPV16 isolates (for example, HPV16 L1 proteins as shown in ANA05496.1, ANA05539.1, AGC65525.1, AAV91659.1 and AAD33259.1). Also, when a sequence fragment of the wild-type HPV16 L1 protein is described, it includes not only a sequence fragment of SEQ ID NO: 1, but also a corresponding sequence fragment in the L1 proteins of various HPV16 isolates. For example, the expression "amino acid residues at positions 292 to 316 of the wild-type HPV16 L1 protein" includes the amino acid residues at positions 292 to 316 of SEQ ID NO: 1, and the corresponding fragments of the L1 proteins of various HPV16 isolates.

[0046] According to the invention, the term "wild-type HPV35 L1 protein" refers to the major capsid protein L1 naturally present in human papillomavirus type 35 (HPV35). The sequence of the wild-type HPV35 L1 protein is well known in the art and can be found in various public databases (e.g., NCBI database accession numbers P27232.2, ACV84022.1, AEI61365.1, AEI61429.1, and ACV84029.1).

[0047] In the present invention, when referring to an amino acid sequence of the wild-type HPV35 L1 protein, it is described with reference to the sequence as shown in SEQ ID NO: 2. For example, the expression "amino acid residue at positions 266 to 288 of the wild-type HPV35 L1 protein" refers to the amino acid residues at positions 266 to 288 of the polypeptide represented by SEQ ID NO: 2. However, it will be understood by those skilled in the art that the wild-type HPV35 can include a variety of isolates, and the various isolates may have differences in the amino acid sequences of their L1 proteins. Further, those skilled in the art would understand that although there might be differences in sequence, the L1 proteins of different isolates of HPV35 have a very high amino acid sequence identity (usually above 95%, such as above 96%, above 97%, above 98%, or above 99%), and have substantially the same biological function. Therefore, in the present invention, the term "wild-type HPV35 L1 protein" includes not only the protein represented by SEQ ID NO: 2, but also the L1 proteins of various HPV35 isolates (for example, HPV35 L1 proteins as shown in P27232.2, ACV84022.1, AEI61365.1, AEI61429.1 and ACV84029.1). Also, when a sequence fragment of the wild-type HPV35 L1 protein is described, it includes not only a sequence fragment of SEQ ID NO: 2 but also a corresponding sequence fragment of the L1 proteins of various HPV35 isolates. For example, the expression "amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein" includes the amino acid residues at positions 266-288 of SEQ ID NO: 2, and the corresponding fragments of the L1 proteins of various HPV35 isolates.

[0048] According to the invention, the term "wild-type HPV31 L1 protein" refers to the major capsid protein L1 naturally present in human papillomavirus type 31 (HPV31). The sequence of the wild-type HPV31 L1 protein is well known in the art and can be found in various public databases (e.g., NCBI database accession numbers P17388.1, AEI60965.1, ANB49655.1, and AEI61021.1).

[0049] In the present invention, when referring to the amino acid sequence of the wild-type HPV31 L1 protein, it is described with reference to the sequence shown in SEQ ID NO: 3. For example, the expression "amino acid residue at positions 177 to 182 of the wild-type HPV31 L1 protein" refers to the amino acid residues at positions 177 to 182 of the polypeptide represented by SEQ ID NO: 3. However, it is understood by those skilled in the art that the wild-type HPV31 may include a plurality of isolates, and the various isolates may have differences in the amino acid sequences of their L1 proteins. Further, those skilled in the art would understand that although there might be differences in sequence, the L1 proteins of different isolates of HPV31 have a very high amino acid sequence identity (usually above 95%, such as above 96%, above 97%, above 98%, or above 99%), and have substantially the same biological function. Therefore, in the present invention, the term "wild-type HPV31 L1 protein" includes not only the protein represented by SEQ ID NO: 3, but also the L1 proteins of various HPV31 isolates (for example, HPV31 L1 proteins as shown in P17388.1, AEI60965.1, ANB49655. 1 and AEI61021.1). Also, when a sequence fragment of the wild-type HPV31 L1 protein is described, it includes not only the sequence fragment of SEQ ID NO: 3, but also a corresponding sequence fragment of the L1 proteins of various HPV31 isolates. For example, the expression "amino acid residues at positions 177 to 182 of the wild-type HPV31 L1 protein" includes the amino acid residues at positions 177 to 182 of SEQ ID NO: 3, and the corresponding fragments of the L1 proteins of various HPV31 isolates.

[0050] According to the invention, the expression "corresponding sequence fragment" or "corresponding fragment" refers to a fragment that are located at an equivalent position of the sequences being compared when the sequences are optimally aligned, i.e. the sequences are aligned to obtain a highest percentage of identity.

[0051] According to the invention, the expression "N-terminal truncation of X amino acids" refers to that the amino acid residues at positions 1 to X of the N-terminus of a protein are substituted with methionine residue encoded by an initiation codon (for initiation of protein translation). For example, a HPV16 L1 protein having a N-terminal truncation of 30 amino acids refers to a protein obtained by substituting the amino acid residues at positions 1 to 30 of the N-terminus of the wild-type HPV16 L1 protein with a methionine residue encoded by an initiation codon.

[0052] According to the invention, the term "variant" refers to a protein whose amino acid sequence has substitution (preferably conservative substitution), addition or deletion of one or several (e.g. 1, 2, 3, 4, 5, 6, 7, 8 or 9) amino acids, or has an identity of at least 90%, 95%, 96%, 97%, 98%, or 99%, as compared with the mutated HPV16 L1 protein according to the invention (for example, the protein as set forth in SEQ ID NO: 7, 9, 10 and 11), and which retains the function of the mutated HPV16 L1 protein. In the present invention, the term "function of the mutated HPV16 L1 protein" refers to a capability of inducing generation of neutralizing antibodies against at least two HPV types (e.g. HPV16 and HPV35, or HPV16, HPV35 and HPV31) in the body. The term "identity" is a measure of similarity between nucleotide sequences or amino acid sequences. Generally, sequences are aligned to get the maximum match. "Identity" itself has a meaning that is well known in the art and can be calculated using published algorithms such as BLAST.

[0053] According to the invention, the term "identity" refers to the match degree between two polypeptides or between two nucleic acids. When two sequences for comparison have the same monomer sub-unit of base or amino acid at a certain site (e.g., each of two DNA molecules has an adenine at a certain site, or each of two polypeptides has a lysine at a certain site), the two molecules are identical at the site. The percent identity between two sequences is a function of the number of identical sites shared by the two sequences over the total number of sites for comparison x 100. For example, if 6 of 10 sites of two sequences are matched, these two sequences have an identity of 60%. For example, DNA sequences: CTGACT and CAGGTT share an identity of 50% (3 of 6 sites are matched). Generally, the comparison of two sequences is conducted in a manner to produce maximum identity. Such alignment can be conducted by for example using a computer program such as Align program (DNAstar, Inc.) which is based on the method of Needleman, et al. (J. Mol. Biol. 48:443-453, 1970). The percentage of identity between two amino acid sequences can also be determined using the algorithm of E. Meyers and W. Miller (Comput. Appl. Biosci., 4:11-17 (1988)) which has been incorporated into the ALIGN program (version 2.0), using a PAM120 weight residue table, and with a gap length penalty of 12 and a gap penalty of 4. In addition, the percentage of identity between two amino acid sequences can be determined by the algorithm of Needleman and Wunsch (J. Mol. Biol. 48:444-453 (1970)) which has been incorporated into the GAP program in the GCG software package (available at http://www.gcg.com), using either a Blossum 62 matrix or a PAM250 matrix, and with a gap weight of 16, 14, 12, 10, 8, 6, or 4 and a length weight of 1, 2, 3, 4, 5, or 6.

[0054] As used herein, the term "conservative substitution" refers to amino acid substitutions which would not disadvantageously affect or change the essential properties of a protein/polypeptide comprising the amino acid sequence. For example, a conservative substitution may be introduced by standard techniques known in the art such as site-directed mutagenesis and PCR-mediated mutagenesis. Conservative amino acid substitutions include substitutions wherein an amino acid residue is substituted with another amino acid residue having a similar side chain, for example, a residue physically or functionally similar (such as, having similar size, shape, charge, chemical property including the capability of forming covalent bond or hydrogen bond, etc.) to the corresponding amino acid residue. The families of amino acid residues having similar side chains have been defined in the art. These families include amino acids having basic side chains (for example, lysine, arginine and histidine), amino acids having acidic side chains (for example, aspartic acid and glutamic acid), amino acids having uncharged polar side chains (for example, glycine, asparagine, glutamine, serine, threonine, tyrosine, cysteine, tryptophan), amino acids having nonpolar side chains (for example, alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine), amino acids having β-branched side chains (such as threonine, valine, isoleucine) and amino acids having aromatic side chains (for example, tyrosine, phenylalanine, tryptophan, histidine). Therefore, generally a conservative substitution refers to a substitution of a corresponding amino acid residue with another amino acid residue from the same side-chain family. Methods for identifying amino acid conservative substitutions are well known in the art (see, for example, Brummell et al., Biochem. 32: 1180-1187 (1993); Kobayashi et al., Protein Eng. 12(10): 879-884 (1999); and Burks et al., Proc. Natl. Acad. Sci. USA 94: 412-417 (1997), which are incorporated herein by reference).

[0055] According to the invention, the term "E. coli expression system" refers to an expression system consisting of E. coli (strain) and a vector, wherein the E. coli (strain) is derived from the commercially available strains, including, but not limited to: ER2566, BL21 (DE3), B834 (DE3), and BLR (DE3).

[0056] According to the invention, the term "vector" refers to a nucleic acid carrier tool which can have a polynucleotide inserted therein. When the vector allows for the expression of the protein encoded by the polynucleotide inserted therein, the vector is called an expression vector. The vector can have the carried genetic material elements expressed in a host cell by transformation, transduction, or transfection into the host cell. Vectors are well known by a person skilled in the art, including, but not limited to plasmids, phages, cosmids, etc.

[0057] According to the invention, the term "a pharmaceutically acceptable carrier and/or excipient" refers to a carrier and/or excipient that is pharmacologically and/or physiologically compatible to a subject and active ingredients, which is well known in the art (see, for example, Remington's Pharmaceutical Sciences. Edited by Gennaro AR, 19th ed. Pennsylvania: Mack Publishing Company, 1995), including, but not limited to: pH regulators, surfactants, adjuvants, and ionic strength enhancers. For example, pH regulators include, but are not limited to, phosphate buffers; surfactants include, but are not limited to: cation surfactants, anion surfactants, or non-ionic surfactants, e.g., Tween-80; adjuvants include, but are not limited to, aluminium adjuvant (e.g., aluminium hydroxide), and Freund's adjuvant (e.g., Freund's complete adjuvant); and ionic strength enhancers include, but are not limited to, NaCl.

[0058] According to the invention, the term "an effective amount" refers to an amount that can effectively achieve the intended purpose. For example, an amount effective for preventing a disease (such as HPV infection) refers to an amount effective for preventing, suppressing, or delaying the occurrence of a disease (such as HPV infection). The determination of such an effective amount is within the ability of a person skilled in the art.

[0059] According to the invention, the term "chromatography" includes, but is not limited to: ion exchange chromatography (such as cation-exchange chromatography), hydrophobic interaction chromatography, absorbent chromatography (such as hydroxyapatite chromatography), gel filtration chromatography (gel exclusion chromatography), and affinity chromatography.

[0060] According to the invention, the term "lysate supernatant" refers to a solution produced by the following steps: host cells (such as E. coli) are disrupted in a lysis buffer, and the insoluble substances are then removed from the lysed solution containing the disrupted host cells. Various lysis buffers are well known in the art, including, but not limited to Tris buffers, phosphate buffers, HEPES buffers, MOPS buffers, etc. In addition, the disrupting of a host cell can be accomplished by methods well known by a person skilled in the art, including, but not limited to homogenizer disrupting, ultrasonic treatment, grinding, high pressure extrusion, lysozyme treatment, etc. Methods for removing insoluble substances are also well known by a person skilled in the art, including, but not limited to filtration and centrifugation.

Beneficial effects of the invention



[0061] Studies have shown that although there is a certain cross-protection between HPV16 and other types of HPV (such as HPV35 and HPV31), such cross-protection has poor potency, which is usually less than one hundredth, even one thousandth of the protection level of VLP of its own type. Therefore, a subject vaccinated with HPV16 vaccine still has a high risk of being infected with other types of HPV (such as HPV35 and HPV31).

[0062] The present invention provides a mutated HPV16 L1 protein and a HPV virus-like particle formed thereby. The HPV virus-like particle of the present invention is capable of providing a significant cross-protection between HPV 16 and other types of HPV (e.g., HPV 35 and HPV 31). In particular, at the same immunizing dose, the HPV virus-like particle of the invention is capable of inducing the generation of high-titer neutralizing antibodies against at least two types of HPV (e.g., HPV 16 and HPV 35, or HPV 16, HPV 35 and HPV 31) in the body, and its effect is comparable to a mixture of VLPs of multiple types of HPV (e.g., a mixture of HPV16 VLP and HPV35 VLP, or a mixture of HPV16 VLP, HPV35 VLP, and HPV31 VLP). Therefore, the HPV virus-like particle of the present invention can be used to simultaneously prevent infections by at least two types of HPV (for example, HPV16 and HPV35, or HPV16, HPV35, and HPV31) and a disease associated therewith, and has significant advantageous technical effects. This has a particularly significant advantage in expanding the scope of protection of HPV vaccines and reducing the cost of production of HPV vaccines.

[0063] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and embodiments. However, those skilled in the art will understand that the following drawings and examples are merely illustrative of the invention and are not intended to limit the scope of the invention. According to following detailed description of the drawings and preferred embodiments, the various objects and advantageous aspects of the invention will be apparent to those skilled in the art.

Description of the Drawings



[0064] 

FIG. 1 shows the results of SDS polyacrylamide gel electrophoresis of the purified mutated protein in Example 1. Lane M: protein molecular weight marker; Lane 1: HPV16N30 (HPV16 L1 protein with N-terminal truncation of 30 amino acids); Lane 2: H16N30-35T1; Lane 3: H16N30-35T2; Lane 4: H16N30-35T3; Lane 5: H16N30-35T4; Lane 6: H16N30-35T5; Lane 7: HPV16N30; Lane 8: H16N30-35T4-31S1; Lane 9: H16N30-35T4-31S2; Lane 10: H16N30-35T4-31S3; Lane 11: H16N30-35T4-31S5. The results showed that after purification by chromatography, the proteins H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 have a purity of not less than 95%.

FIG. 2 shows the results of Western Blot detection of H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3 and H16N30-35T4-31S5 prepared in Example 1 using a broad-spectrum antibody 4B3. Lane M: protein molecular weight marker; Lane 1: HPV16N30; Lane 2: H16N30-35T1; Lane 3: H16N30-35T2; Lane 4: H16N30-35T3; Lane 5: H16N30-35T4; Lane 6: H16N30-35T5; Lane 7: HPV16N30; Lane 8: H16N30-35T4-31S1; Lane 9: H16N30-35T4-31S2; Lane 10: H16N30-35T4-31S3; Lane 11: H16N30-35T4-31S5. The results showed that the mutated proteins H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 can be specifically recognized by broad-spectrum antibody 4B3.

FIGs. 3A-3L show the results of molecular sieve chromatography analysis of samples containing proteins HPV16N30, HPV35 L1, HPV31 L1, H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3 and H16N30-35T4-31S5. FIG. 3A: HPV16N30; FIG. 3B: HPV35 L1; FIG. 3C: HPV31 L1; FIG. 3D: H16N30-35T1; FIG. 3E: H16N30-35T2; FIG. 3F: H16N30-35T3; FIG. 3G: H16N30-35T4; FIG. 3H: H16N30- 35T5; FIG. 3I: H16N30-35T4-31S1; FIG. 3J: H16N30-35T4-31S2; FIG. 3K: H16N30-35T4-31S3; FIG. 3L: H16N30-35T4-31S5. The results showed that the first protein peaks of each sample appeared at around 12 min, which were comparable to that of the VLP assembled from HPV16N30 protein (HPV16N30 VLP), the VLP assembled from HPV35 L1 protein (HPV35 VLP), and the VLP assembled from HPV31 L1 protein (HPV31 VLP). This indicates that all of the above mutated proteins can be assembled into VLPs.

FIGs. 4A-4L show the results of sedimentation rate analysis for HPV16N30 VLP, HPV35 VLP, HPV31 VLP, H16N30-35T1 VLP, H16N30-35T2 VLP, H16N30-35T3 VLP, H16N30-35T4 VLP, H16N30-35T5 VLP, H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP, H16N30-35T4-31S3 VLP, H16N30-35T4-31S5 VLP. FIG. 4A, HPV16N30 VLP; FIG. 4B, HPV35 VLP; FIG. 4C, HPV31 VLP; FIG. 4D, H16N30-35T1 VLP; FIG. 4E, H16N30-35T2 VLP; FIG. 4F, H16N30-35T3 VLP; FIG. 4G, H16N30-35T4 VLP; FIG. 4H, H16N30-35T5 VLP; FIG. 4I, H16N30-35T4-31S1 VLP; FIG. 4J, H16N30-35T4-31S2 VLP; FIG. 4K, H16N30-35T4-31S3 VLP; FIG. 4L, H16N30-35T4-31S5 VLP. The results showed that the sedimentation coefficients of the H16N30-35T1 VLP, H16N30-35T2 VLP, H16N30-35T3 VLP, H16N30-35T4 VLP, H16N30-35T5 VLP, H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP, H16N30-35T4-31S3 VLP, H16N30-35T4-31S5 VLP are similar to those of the HPV16N30 VLP, HPV35 VLP, and HPV31 VLP. This indicates that the H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 are assembled into virus-like particles similar to wild-type VLP in terms of size and morphology.

FIGs. 5A-5L show the results of transmission electron microscopy observation for various VLP samples (at a magnification of 100,000 times, Bar = 0.1 µm). FIG. 5A, VLP assembled by HPV16N30; FIG. 5B, VLP assembled by HPV35 L1; FIG. 5C, VLP assembled by HPV31 L1; FIG. 5D, VLP assembled by H16N30-35T1; FIG. 5E, VLP assembled by H16N30-35T2; FIG. 5F, VLP assembled by H16N30-35T3; FIG. 5G, VLP assembled by H16N30-35T4; FIG. 5H, VLP assembled by H16N30-35T5; FIG. 5I, VLP assembled by H16N30-35T4-31S1; FIG. 5J, VLP assembled from H16N30-35T4-31S2; FIG. 5K, VLP assembled from H16N30-35T4-31S3; FIG. 5L, VLP assembled from H16N30-35T4-31S5. The results showed that the H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3 and H16N30-35T4-31S5 are similar to HPV16N30, HPV35 L1 and HPV31 L1 proteins, and can be assembled into VLPs with a radius of about 30 nm.

FIGs. 6A-6L show the results of thermal stability evaluation for HPV16N30 VLP, HPV35 VLP, HPV31 VLP, H16N30-35T1 VLP, H16N30-35T2 VLP, H16N30-35T3 VLP, H16N30-35T4 VLP, H16N30-35T5 VLP, H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP, H16N30-35T4-31S3 VLP, H16N30-35T4-31S5 VLP. FIG. 6A, HPV16N30 VLP; FIG. 6B, HPV35 VLP; FIG. 6C, HPV31 VLP; FIG. 6D, H16N30-35T1 VLP; FIG. 6E, H16N30-35T2 VLP; FIG. 6F, H16N30-35T3 VLP; FIG. 6G, H16N30-35T4 VLP; FIG. 6H, H16N30-35T5 VLP; FIG. 6I, H16N30-35T4-31S1 VLP; FIG. 6J, H16N30-35T4-31S2 VLP; FIG. 6K, H16N30-35T4-31S3 VLP; FIG. 6L, H16N30-35T4-31S5 VLP. The results indicate that the VLP formed by each protein has extremely high thermal stability.

FIG. 7A shows the evaluation results of immunoprotection of the experimental groups of H16N30-35T1 VLP, H16N30-35T2 VLP, H16N30-35T3 VLP, H16N30-35T4 VLP, H16N30-35T5 VLP and the control groups of HPV16N30 VLP, HPV35 VLP and the mixed HPV16/HPV35 VLP in mice. The results showed that the H16N30-35T4 VLP induced high-titer neutralizing antibodies against HPV16 and HPV35 in mice; and its protective effect against HPV16 was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35 VLP, and was significantly higher than that of the HPV35 VLP alone; in addition, its protective effect against HPV35 was comparable to those of the HPV35 VLP alone, the mixed HPV16/HPV35 VLP, and was significantly higher than that of the HPV16N30 VLP alone. This indicates that the H16N30-35T4 VLP can be used as an effective vaccine against HPV16 infection and HPV35 infection, and can be used in place of the mixed vaccine containing HPV16 VLP and HPV35 VLP.

FIG. 7B shows the evaluation results of immunoprotection of the experimental groups of H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP, H16N30-35T4-31S3 VLP and H16N30-35T4-31S5 VLP, and the control groups of HPV16N30 VLP, HPV31 VLP, HPV35 VLP and the mixed HPV16/ HPV35/HPV31 VLP in mice. The results showed that the H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP and H16N30-35T4-31S3 VLP induced high-titer neutralizing antibodies against HPV16, HPV35 and HPV31 in mice; and their protection effects against HPV16 were comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and were significantly higher than those of the HPV35 VLP alone and the HPV31 VLP alone; and their protective effects against HPV35 were comparable to those of the HPV35 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and were significantly higher than those of the HPV16N30 VLP alone and the HPV31 VLP alone; and their protection effects against HPV31 were comparable to those of the HPV31 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and were significantly higher than those of the HPV16N30 VLP alone and the HPV35 VLP alone. This indicates that the H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP and H16N30-35T4-31S3 VLP can be used as effective vaccines against HPV16 infection, HPV35 infection and HPV31 infection, and can be used in place of the mixed vaccine containing HPV16 VLP, HPV35 VLP and HPV31 VLP.

FIGs. 8A-8C show the evaluation results of neutralizing antibody titers in mouse serum after immunization of mice with H16N30-35T4 VLP. FIG. 8A: 10 µg dose group (immunization dose was 10 µg, using aluminum adjuvant); FIG. 8B: 1 µg dose group (immunization dose was 1 µg, using aluminum adjuvant); FIG. 8C: 0.1 µg dose group (immunization dose was 0.1 µg, using aluminum adjuvant). The results showed that the H16N30-35T4 VLP induced high titers of neutralizing antibodies against HPV16 in mice, and its protective effect was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35 VLP at the same dose, and was significantly better than that of the HPV35 VLP alone at the same dose; and it also induced high titers of neutralizing antibodies against HPV35 in mice, and its protective effect was comparable to those of the HPV35 VLP alone and the mixed HPV16/HPV35 VLP at the same dose, and was significantly better than that of the HPV16N30 VLP alone at the same dose. This indicates that the H16N30-35T4 VLP has good cross-immunogenicity and cross-protection against HPV16 and HPV35.

FIGs. 8D-8F show the evaluation results of neutralizing antibody titers in mouse serum after immunization of mice with H16N30-35T4-31S3 VLP. FIG. 8D: 10 µg dose group (immunization dose was 10 µg, using aluminum adjuvant); FIG. 8E: 1 µg dose group (immunization dose was 1 µg, using aluminum adjuvant); FIG. 8F: 0.1 µg dose group (immunization dose was 0.1 µg, using aluminum adjuvant). The results showed that the H16N30-35T4-31S3 VLP induced high titers of neutralizing antibodies against HPV16 in mice, and its protective effect was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35/HPV31 VLP at the same dose, and was significantly better than that of the HPV35 VLP alone or the HPV31 VLP alone at the same dose; and it also induced high titers of neutralizing antibodies against HPV35 in mice, and its protective effect was comparable to those of the HPV35 VLP alone and the mixed HPV16/HPV35/HPV31 VLP at the same dose, and was significantly better than that of the HPV16N30 VLP alone or the HPV31 VLP alone at the same dose; and also it induced high titers of neutralizing antibodies against HPV31 in mice, and its protective effect was comparable to those of the HPV31 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and was significantly better than that of the HPV16N30 VLP alone or the HPV35 VLP alone at the same dose. This indicates that the H16N30-35T4-S3 VLP has good cross-immunogenicity and cross-protection against HPV16, HPV35 and HPV31.


Sequence information



[0065] Some of the sequences involved in the present invention are provided in Table 1 below.
Table 1: Description of sequences
SEQ ID NO:Description
1 wild-type HPV16 L1 protein
2 wild-type HPV35 L1 protein
3 wild-type HPV31 L1 protein
4 The mutated HPV16 L1 protein containing Segment 1 of HPV35 L1 protein, H16N30-35T1
5 The mutated HPV16 L1 protein containing Segment 2 of HPV35 L1 protein, H16N30-35T2
6 The mutated HPV16 L1 protein containing Segment 3 of HPV35 L1 protein, H16N30-35T3
7 The mutated HPV16 L1 protein containing Segment 4 of HPV35 L1 protein, H16N30-35T4
8 The mutated HPV16 L1 protein containing Segment 5 of HPV35 L1 protein, H16N30-35T5
9 The mutated HPV16 L1 protein containing Segment 4 of HPV35 L1 protein and Segment 1 of HPV31 L1 protein, H16N30-35T4-31S1
10 The mutated HPV16 L1 protein containing Segment 4 of HPV35 L1 protein and Segment 2 of HPV31 L1 protein, H16N30-35T4-31S2
11 The mutated HPV16 L1 protein containing Segment 4 of HPV35 L1 protein and Segment 3 of HPV31 L1 protein, H16N30-35T4-31S3
12 The mutated HPV16 L1 protein containing Segment 4 of HPV35 L1 protein and Segment 5 of HPV31 L1 protein, H16N30-35T4-31S5
13 DNA sequence encoding SEQ ID NO: 1
14 DNA sequence encoding SEQ ID NO:2
15 DNA sequence encoding SEQ ID NO:3
16 DNA sequence encoding SEQ ID NO:4
17 DNA sequence encoding SEQ ID NO:5
18 DNA sequence encoding SEQ ID NO:6
19 DNA sequence encoding SEQ ID NO:7
20 DNA sequence encoding SEQ ID NO:8
21 DNA sequence encoding SEQ ID NO:9
22 DNA sequence encoding SEQ ID NO: 10
23 DNA sequence encoding SEQ ID NO: 11
24 DNA sequence encoding SEQ ID NO: 12
25 Sequence of amino acid residues at positions 266-288 of wild-type HPV35 L1 protein
26 Sequence of amino acid residues at positions 50-62 of wild-type HPV31 L1 protein
27 Sequence of amino acid residues at positions 127-142 of wild-type HPV31 L1 protein
28 Sequence of amino acid residues at positions 177-182 of wild-type HPV31 L1 protein












































































Sequence 25 (SEQ ID NO:25):
TVGETVPADLYIKGTTGTLPSTS

Sequence 26 (SEQ ID NO:26):
YSIPKSDNPKKIV

Sequence 27 (SEQ ID NO:27):
FDDTENSNRYAGGPGT

Sequence 28 (SEQ ID NO:28):
SNNAIT


Specific Models For Carrying Out the Invention



[0066] The invention is described with reference to the following examples which are intended to illustrate, but not limit the invention.

[0067] Unless otherwise specified, the molecular biology experimental methods and immunoassays used in the present invention were carried out substantially by referring to the procedures of J. Sambrook et al., Molecular Cloning: A Laboratory Manual, 2nd Edition, Cold Spring Harbor Laboratory Press, 1989, and F. M. Ausubel et al., Short Protocols in Molecular Biology, 3rd Edition, John Wiley & Sons, Inc., 1995; restriction endonucleases were used under the conditions recommended by the manufacturers. It will be understood by those skilled in the art that the present invention is described by way of examples, and the examples are not intended to limit the scope of the invention.

Example 1. Expression and purification of mutated HPV16 L1 protein


Construction of expression vector



[0068] An expression vector encoding the mutated HPV16 L1 protein containing Segment 3 or Segment 5 derived from HPV35 L1 protein was constructed by PCR for multi-site mutagenesis, in which the initial template used was pTO-T7-HPV16L1N30C plasmid (which encoded the HPV16 L1 protein with a N-terminal truncation of 30 amino acids (this protein was named as HPV16N30); abbreviated as 16L1N30 in Table 2). The templates and primers used for each PCR reaction were shown in Table 2, and the amplification conditions of the PCR reaction were set as: denaturating at 94 °C for 10 minutes; 25 cycles of (denaturating at 94 °C for 50 seconds, annealing at a specified temperature for a certain time, extending at 72 °C for 7 minutes and 30 seconds); finally extending at 72 °C for 7 minutes. The sequences of the used PCR primers were listed in Table 3.

[0069] 2 µL of restriction endonuclease DpnI was added to the amplification product (50 µL), and incubated at 37 °C for 60 minutes. 10 µL of the enzyme-digested product was used for transformation of 40 µL of competent E. coli ER2566 (purchased from New England Biolabs) prepared by the calcium chloride method. The transformed E. coli was spread onto a solid LB medium (LB medium components: 10 g/L peptone, 5 g/L yeast powder, 10 g/L sodium chloride, the same hereinafter) containing kanamycin (final concentration: 25 mg/mL, the same hereinafter), and was subjected to static culture at 37 °C for 10-12 hours until single colonies were observed clearly. Single colonies were picked and inoculated into a test tube containing 4 mL of liquid LB medium (containing kanamycin), and cultured with shaking at 220 rpm for 10 hours at 37 °C. Subsequently, 1 mL of the bacterial solution was taken and stored at -70 °C. Plasmid was extracted from the E. coli, and the nucleotide sequences of the target fragments inserted into the plasmid were sequenced using T7 primer. The sequencing results showed that the nucleotide sequences of the target fragments inserted in each of the constructed plasmids (expression vectors) were SEQ ID NOs: 18 and 20, respectively, and the amino acid sequences encoded thereby were SEQ ID NOs: 6 and 8 (the corresponding proteins were named as H16N30-35T3 and H16N30-35T5, respectively).

[0070] The mutated protein H16N30-35T3 differed from HPV16N30 in that the amino acid residues at positions 199-210 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 173-184 of the wild-type HPV35 L1 protein. The mutated protein H16N30-35T5 differed from HPV16N30 in that the amino acid residues at positions 374-384 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 346-356 of the wild-type HPV35 L1 protein.

[0071] An expression vector of the mutated HPV16 L1 protein containing Segment 1, Segment 2 or Segment 4 derived from HPV35 L1 protein was constructed by using Gibson assembly (Gibson DG, Young L, Chuang RY, Venter JC, Hutchison CA, Smith HO. Enzymatic assembly of DNA molecules up to several hundred kilobases. Nat Methods. 2009; 6:343-5. doi: 10.1038/nmeth. 1318). Briefly, a short fragment containing a mutation and a long fragment containing no mutation were first obtained by PCR reaction, and then the two fragments were ligated into a loop using a Gibson assembly system. The initial template used was pTO-T7-HPV16L1N30C plasmid and pTO-T7-HPV35L1 plasmid (which encoded HPV35 L1 protein; abbreviated as 35L1 in Table 2). The templates and primers used for the respective PCR reactions were shown in Table 2, and the amplification conditions for the PCR reaction for amplifying the short fragment were set as: denaturating at 94 °C for 10 minutes; 25 cycles of (denaturating at 94 °C for 50 seconds, annealing at a specified temperature for a certain time, extending at 72 °C for 1 minute); finally extending at 72 °C for 10 minutes. The amplification conditions for the PCR reaction for amplifying the long fragment were set as: denaturating at 94 °C for 10 minutes; 25 cycles of (denaturating at 94 °C for 50 seconds, annealing at a specified temperature for a certain time, extending at 72 °C for 7 minutes and 30 seconds); finally extending at 72 °C for 10 minutes. The sequences of the PCR primers used were listed in Table 3. The amplified product was subjected to electrophoresis, and then the target fragments were recovered using a DNA recovery kit and their concentrations were determined. The amplified short and long fragments were mixed at a molar ratio of 2:1 (total volume of 3 µL), followed by the addition of 3 µL of 2X Gibson Assembly premixes (2 X Gibson Assembly Master Mix, purchased from NEB, containing T5 exonuclease, Phusion DNA polymerase, Taq DNA ligase), and reacted at 50 °C for 1 hour.

[0072] 40 µL of competent E. coli ER2566 (purchased from New England Biolabs) prepared by the calcium chloride method was transformed with the assembled product (6 µL). The transformed E. coli was spread on a solid LB medium containing kanamycin and were subjected to static culture at 37 °C for 10-12 hours until the single colonies were observed clearly. Single colonies were picked and inoculated into a test tube containing 4 mL of a liquid LB medium (containing kanamycin), and cultured with shaking at 220 rpm for 10 hours at 37 °C. Subsequently, 1 mL of the bacterial solution was taken and stored at -70 °C. The plasmid was extracted from E. coli, and the nucleotide sequences of the target fragments inserted into the plasmid were sequenced using T7 primer. The sequencing results showed that the nucleotide sequences of the target fragments inserted in each of the constructed plasmids (expression vectors) were SEQ ID NOs: 16, 17, and 19, respectively, and the amino acid sequences encoded thereby were SEQ ID NOs: 4, 5, and 7 (the corresponding proteins were named as H16N30-35T1, H16N30-35T2 and H16N30-35T4, respectively).

[0073] The mutated protein H16N30-35T1 differed from HPV16N30 in that the amino acid residues at positions 76-87 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 50-61 of the wild-type HPV35 L1 protein. The mutated protein H16N30-35T2 differed from HPV16N30 in that the amino acid residues at positions 158-167 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 132-141 of the wild-type HPV35 L1 protein. The mutated protein H16N30-35T4 differed from HPV16N30 in that the amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein.

[0074] An expression vector encoding the mutated HPV16 L1 protein with double-substitution which contains a segment derived from HPV35 L1 and a segment derived from HPV31 L1, was constructed by using Gibson assembly. Briefly, a short fragment containing a mutation and a long fragment containing no mutation were firstly obtained by PCR reaction, and then the two fragments were ligated into a loop using a Gibson assembly system. The initial template used included pTO-T7-H16N30-35T4 plasmid (which encoded the mutated protein H16N30-35T4; abbreviated as H16N30-35T4 in Table 2), and pTO-T7-HPV31L1 plasmid (which encoded HPV31 L1 protein; abbreviated as 31L1 in Table 2). The templates and primers used for the respective PCR reactions were shown in Table 2, and the amplification conditions for the PCR reaction for amplifying the short fragment were set as: denaturating at 94 °C for 10 minutes; 25 cycles of (denaturating at 94 °C for 50 seconds, annealing at a specified temperature for a certain time, extending at 72 °C for 1 minute); finally extending at 72 °C for 10 minutes. The amplification conditions for the PCR reaction for amplifying the long fragment were set as: denaturating at 94 °C for 10 minutes; 25 cycles of (denaturating at 94 °C for 50 seconds, annealing at a specified temperature for a certain time, extending at 72 °C for 7 minutes and 30 seconds); finally extending at 72 °C for 10 minutes. The sequences of the PCR primers used are listed in Table 3. The amplified product was subjected to electrophoresis, and then the target fragments were recovered using a DNA recovery kit and its concentration was determined. The amplified short and long fragments were mixed at a molar ratio of 2:1 (total volume of 3 µL), followed by the addition of 3 µL of 2X Gibson Assembly premixes (2 X Gibson Assembly Master Mix, purchased from NEB, containing T5 exonuclease, Phusion DNA polymerase, Taq DNA ligase), and reacted at 50 ° C for 1 hour.

[0075] 40 µL of competent E. coli ER2566 (purchased from New England Biolabs) prepared by the calcium chloride method was transformed with the assembled product (6 µL). The transformed E. coli was spread on a solid LB medium containing kanamycin and subjected to static culture at 37 °C for 10-12 hours until the single colonies were observed clearly. Single colonies were picked and inoculated into a test tube containing 4 mL of a liquid LB medium (containing kanamycin), and cultured with shaking at 220 rpm for 10 hours at 37 °C. Subsequently, 1 mL of the bacterial solution was taken and stored at -70 °C. The plasmid was extracted from E. coli, and the nucleotide sequences of the target fragments inserted into the plasmid was sequenced using T7 primer. The sequencing results showed that the nucleotide sequences of the desired fragments inserted in each of the constructed plasmids (expression vectors) were SEQ ID NOs: 21, 22, 23, and 24, respectively, and the amino acid sequences encoded thereby were SEQ ID NOs: 9, 10, 11, 12 (the corresponding proteins were named as H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, and H16N30-35T4-31S5).

[0076] The mutated protein H16N30-35T4-31S1 differed from HPV16N30 in that the amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein, and the amino acid residues at positions 76-87 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 50-62 of the wild-type HPV31 L1 protein. The mutated protein H16N30-35T4-31S2 differed from HPV16N30 in that the amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein, and the amino acid residues at positions 152-167 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 127-142 of the wild-type HPV31 L1 protein. The mutated protein H16N30-35T4-31S3 differed from HPV16N30 in that the amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein, and the amino acid residues at positions 202-207 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 177-182 of the wild type HPV31 L1 protein. The mutated protein H16N30-35T4-31S5 differed from HPV16N30 in that the amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein, and the amino acid residues at positions 375-384 of the wild-type HPV16 L1 protein were replaced with the amino acid residues at positions 350-359 of the wild-type HPV31 L1 protein.
Table 2. Templates and primers for PCR reactions used to construct expression vectors
TemplateUpstream primerDownstream primerProduct
16L1N30 G-V-H16N30-35T1-F G-V-H16N30-35T1-R H16N30-35T1 long fragment
35L1 G-H16N30-35T1-F G-H16N30-35T1-R H16N30-3ST1 short fragment
16L1N30 G-V-H16N30-35T2-F G-V-H16N30-35T2-R long fragment
35L1 G-H16N30-35T2-F G-H16N30-35T2-R -35T2 short fragment
16L1N30 H16N30-35T3-F H16N30-35T3-R H16N30-35T3
16L1N30 G-V-H16N30-35T4-F G-V-H16N30-35T4-R long fragment
35L1 G-H16N30-35T4-F G-H16N30-35T4-R -35T4 short fragment
16L1N30 H16N30-35T5-F H16N30-35T5-R H16N30-35T5
H16N30-35T4 G-V-H16N30-35T4-31S1-F G-V-H16N30-35T4-3IS1-R H16N30-3ST4-31S1 long fragment
31L1 G-H16N30-35T4-31S1-F G-H16N30-35T4-31S1-R short fragment
H16N30-35T4 G-V-H16N30-35T4-31S2-F G-V-H16N30-35T4-31S2-R H16N30-35T4-31S2 long fragment
31L1 G-H16N30-35T4-31S2-F G-H16N30-35T4-31S2-R H16N30-35T4-31S2 short fragment
H16N30-35T4 G-V -H16N30-35T4-31S3-F G-V-H16N30-35T4-31S3-R H16N30-3ST4-31S3 long fragment
31L1 G-H16N30-35T4-31S3-F G-H16N30-35T4-31S3-R H16N30-35T4-31S3 short fragment
H16N30-35T4 G-V-H16N30-35T4-31S5-F G-V-H16N30-35T4-31S5-R H16N30-35T4-31S5 long fragment
31L1 G-H16N30-35T4-31S5-F G-H16N30-35T4-31S5-R H16N30-35T4-31S5 short fragment
Table 3: Sequences of the used primers (SEQ ID NO: 29-60)
SEQ ID NO:Primer namePrimer sequence (5'-3')
29 G-V-H16N30-35T1-F ATACATTTACCTGACCCCAATAAG
30 G-V-H16N30-35T1-R TGTTCCTGCATGATAATATATGTTTG
31 G-H16N30-35T1-F

 
32 G-H16N30-35T1-R

 
33 G-V-H16N30-35T2-F AAACCACCTATAGGGGAACACTG
34 G-V-H16N30-35T2-R TACACAGGCCCAAACCAGCCGC
35 G-H16N30-35T2-F

 
36 G-H16N30-35T2-R

 
37 H16N30-35T3-F

 
38 H16N30-35T3-R

 
39 G-V-H16N30-35T4-F TGGGGTAACCAACTATTTGTTACTG
40 G-V-H16N30-35T4-R TAAGCTGTCGCCATATGGTTCTG
41 G-H16N30-35T4-F

 
42 G-H16N30-35T4-R

 
43 H16N30-35T5-F

 
44 H16N30-35T5-R

 
45 G-V-H16N30-35T4-31S1-F ATACATTTACCTGACCCCAATAAGTT
46 G-V-H16N30-35T4-31S1-R TGCAAGTAGTCTGGATGTTCCTGC
47 G-H16N30-35T4-31S1-F

 
48 G-H16N30-35T4-31S1-R

 
49 G-V-H16N30-35T4-31S2-F ATTGGTTGCAAACCACCTATAGGGG
50 G-V-H16N30-35T4-31S2-R AACACCTACACAGGCCCAAACCAGC
51 G-H16N30-35T4-31S2-F

 
52 G-H16N30-35T4-31S2-R

 
53 G-V-H16N30-35T4-31S3-F ATAAACACAGTTATTCAGGATGG
54 G-V-H16N30-35T4-31S3-R AATTAAACACAATTGTGTTTGTTTGT
55 G-H16N30-35T4-31S3-F

 
56 G-H16N30-35T4-31S3-R

 
57 G-V-H16N30-35T4-31S5-F TATGATTTACAGTTTATTTTTC
58 G-V-H16N30-35T4-31S5-R TAATGACATATTTGTACTGCGTG
59 G-H16N30-35T4-31S5-F

 
60 G-H16N30-35T4-31S5-R

 

Expression of mutated proteins on a large scale



[0077] The bacteria liquids of E. coli carrying recombinant plasmids pTO-T7-H16N30-35T1, pTO-T7-H16N30-35T2, pTO-T7-H16N30-35T3, pTO-T7-H16N30-35T4, pTO-T7-H16N30-35T5, pTO-T7-H16N30-35T4-31S1, pTO-T7-H16N30-35T4-31S2, pTO-T7-H16N30-35T4-31S3, pTO-T7-H16N30-35T4-31S5 were taken out from the -70°C refrigerator, separately inoculated into 100ml of kanamycin-containing LB liquid medium, and cultured at 200 rpm and 37 °C for about 8 hours; then transferred and inoculated into 500 ml of kanamycin-containing LB medium (1 ml of bacterial liquid was inoculated), and cultured continuously. When the bacterial concentration reached an OD600 of about 0.6, the culture temperature was lowered to 25 °C, and 500 µL of IPTG was added to each culture flask, and the culturing was continued for 8 hours. At the end of culturing, the bacterial cells were collected by centrifugation. The bacterial cells separately expressing H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 proteins were obtained.

Disruption of bacterial cells expressing mutated proteins



[0078] The obtained cells were resuspended in a ratio of 1 g of bacterial cells to 10 mL of a lysate (20 mM Tris buffer, pH 7.2, 300 mM NaCl). The cells were disrupted by a ultrasonicator for 30 minutes. The lysate containing the disrupted cells was centrifuged at 13500 rpm (30000 g) for 15 minutes, and the supernatant (i.e., the supernatant of the disrupted bacterial cells) was taken.

Chromatographic purification of mutated proteins



[0079] Instrument System: AKTA explorer 100 preparative liquid chromatography system, manufactured by GE Healthcare (formerly, Amershan Pharmacia).

[0080] Chromatographic media: SP Sepharose 4 Fast Flow (GE Healthcare), CHT-II (purchased from Bio-RAD), and Butyl Sepharose 4 Fast Flow (GE Healthcare).

[0081] Buffer solutions: 20 mM phosphate buffer, pH 8.0, 20 mM DTT; and, 20 mM phosphate buffer, pH 8.0, 20 mM DTT, 2 M NaCl.

[0082] Samples: the obtained supernatants of the disrupted bacterial cells containing H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5, respectively.

[0083] Elution procedure:
  1. (1) Cation exchange purification of the supernatants of the disrupted bacterial cells were carried out by using SP Sepharose 4 Fast Flow: the sample was loaded to a column, and then a buffer containing 400 mM NaCl was used to elute undesired proteins, and a buffer containing 800 mM NaCl was used to elute target protein, the fraction eluted by the buffer containing 800 mM NaCl was collected;
  2. (2) Chromatographic purification of the eluted fraction obtained in the previous step was carried out by using CHT II (hydroxyapatite chromatography): the eluted fraction obtained in the previous step was diluted to reduce the concentration of NaCl to 0.5 M; the sample was loaded to a column, and then a buffer containing 500 mM NaCl was used to elute undesired proteins, and a buffer containing 1000 mM NaCl was used to elute target protein, and the fraction eluted by the buffer containing 1000 mM NaCl was collected;
  3. (3) Chromatographic purification of the eluted fraction obtained in the previous step was carried out by using HIC (hydrophobic interaction chromatography): the sample was loaded to a column, and then a buffer containing 1000 mM NaCl was used to elute undesired proteins, and a buffer containing 200 mM NaCl was used to elute target protein, and the fraction eluted by the buffer containing 200 mM NaCl was collected.


[0084] 150 µL of the eluted fraction obtained in step (3) was taken, added to 30 µL of 6X Loading Buffer, mixed, and incubated in a water bath at 80 °C for 10 min. Then, 10 µ1 of the sample was electrophoresed in a 10% SDS-polyacrylamide gel at 120 V for 120 min; and the electrophoresis band was visualized by Coomassie blue staining. The results of electrophoresis were shown in FIG. 1. The results showed that after the above purification steps, the proteins H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 all had a purity of greater than 95%.

[0085] By similar methods, HPV16N30 protein was prepared and purified using E. coli and pTO-T7-HPV16LlN30C plasmid; HPV35 L1 protein (SEQ ID NO: 2) was prepared and purified using E. coli and pTO-T7-HPV35L1 plasmid; HPV31 L1 protein (SEQ ID NO: 3) was prepared and purified using E. coli and pTO-T7-HPV31L1 plasmid.

Western blotting of mutated proteins



[0086] The purified proteins H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 were subjected to electrophoresis by the above methods. After electrophoresis, Western Blot detection was carried out using a broad-spectrum antibody 4B3 against HPV L1 protein, and the results were shown in FIG. 2. The results showed that the H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 could be specifically recognized by the broad-spectrum antibody 4B3.

Example 2: Assembly and particle morphology detection of HPV virus-like particles


Assembly of HPV virus-like particles



[0087] A given volume (about 2ml) of the protein H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, or H16N30-35T4-31S5 was dialyzed to (1) 2L storage buffer (20mM sodium phosphate buffer, pH 6.5, 0.5M NaC1); (2) 2L renaturation buffer (50mM sodium phosphate buffer, pH 6.0, 2mM CaCl2, 2mM MgCl2, 0.5 M NaCl); and (3) 20 mM sodium phosphate buffer, pH 7.0, 0.5M NaCl, successively. The dialysis was carried out for 12 h in each of the three buffers.

[0088] By similar method, the proteins HPV16N30, HPV35 L1 and HPV31 L1 were assembled into HPV16N30 VLP, HPV35 VLP and HPV31 VLP, respectively.

Molecular sieve chromatography analysis



[0089] The dialyzed samples were analyzed by molecular sieve chromatography using a 1120 Compact LC high performance liquid chromatography system from Agilent, USA, using an analytical column of TSK Gel PW5000x17.8 x 300 mm. The results of the analysis were shown in FIGs. 3A-3L. The results showed that for the samples containing proteins H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5, the first protein peaks appeared at around 12 minutes, which was comparable to that of the HPV16N30 VLP, HPV35 VLP and HPV31 VLP. This indicated that the above-prepared proteins were assembled into VLPs.

Sedimentation velocity analysis



[0090] The instrument used for sedimentation velocity analysis was a Beckman XL-A analytical type ultracentrifuge equipped with optical inspection system, and An-50Ti and An-60Ti rotors. Sedimentation velocity method was used to analyze the sedimentation coefficients of HPV16N30 VLP, HPV35 VLP, HPV31 VLP, H16N30-35T1 VLP, H16N30-35T2 VLP, H16N30-35T3 VLP, H16N30-35T4 VLP, H16N30-35T5 VLP, H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP, H16N30-35T4-31S3 VLP, H16N30-35T4-31S5 VLP. The results were shown in FIGs. 4A-4L. The results showed that the sedimentation coefficients of the H16N30-35T1 VLP, H16N30-35T2 VLP, H16N30-35T3 VLP, H16N30-35T4 VLP, H16N30-35T5 VLP, H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP, H16N30-35T4-31S3 VLP, H16N30-35T4-31S5 VLP were similar to those of the HPV16N30 VLP, HPV35 VLP and HPV31 VLP. This indicated that the H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 were assembled into virus-like particles similar to wild-type VLP in term of size and morphology.

Morphological detection of virus-like particles



[0091] 100 µL of the sample containing VLP was taken for observation of transmission electron microscopy. The instrument used was a 100 kV transmission electron microscope manufactured by JEOL, at a magnification of 100,000 times. Briefly, 13.5 µL of the sample was taken, negatively stained with 2% phosphotungstic acid at pH 7.0, and fixed on a carbon-coated copper mesh, and then observed by the transmission electron microscopy. The results of the observation were shown in FIGs. 5A-5L. The results showed that the H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 were all assembled into virus-like particles. In addition, the results also showed that the particles formed by these mutated proteins had a radius of about 30 nm, and were uniform in size. This indicated that these mutated proteins were similar to the L1 proteins of HPV16, HPV35 and HPV31, and were capable of forming VLPs of uniform size.

Example 3: Evaluation of thermal stability of virus-like particles



[0092] The thermal stability of the VLPs formed by H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 were evaluated using a differential temperature calorimeter VP Capillary DSC purchased from GE Corporation (formerly, MicroCal Corporation), in which the storage buffer of the proteins was used as a control, and each of the proteins was scanned under a heating rate of 1.5 °C/min within a range from 10 °C to 90 °C. The test results were shown in FIGs. 6A-6L. The results showed that the VLP formed by each of the proteins had extremely high thermal stability.

Example 4: Evaluation 1 of immunoprotection of virus-like particles in animals



[0093] The immunoprotective properties of VLPs formed by H16N30-35T1, H16N30-35T2, H16N30-35T3, H16N30-35T4, H16N30-35T5, H16N30-35T4-31S1, H16N30-35T4-31S2, H16N30-35T4-31S3, H16N30-35T4-31S5 were evaluated using mice. The animals used for immunization were 5-6 week old BalB/c mice (ordinary grade) (purchased from Shanghai SLAC Laboratory Animal Co., Ltd.).

[0094] The above-prepared H16N30-35T1 VLP, H16N30-35T2 VLP, H16N30-35T3 VLP, H16N30-35T4 VLP, H16N30-35T5 VLP, HPV16N30 VLP, HPV35 VLP, and the mixed HPV16/HPV35 VLP (i.e., a mixture of HPV16N30 VLP and HPV35 VLP) were adsorbed onto aluminum adjuvant, respectively. The mice were divided into 8 groups according to different immunogens, and each group contained 5 mice. The immunization procedure was: primary immunization was carried out at the 0th week; and booster immunizations were carried out at the 2nd and 4th weeks respectively. The immunization method was intraperitoneal injection, and the immunogens and doses used were as shown in Table 4. At the 8th week after the primary immunization, venous blood was collected from eyeball, and the serum was separated, and then the titers of the neutralizing antibodies in the serum were measured. The test results were shown in FIG. 7A. The results showed that the H16N30-35T4 VLP induced high-titer neutralizing antibodies against HPV16 and HPV35 in mice; and its protective effect against HPV16 was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35 VLP, and was significantly higher than that of the HPV35 VLP alone; and its protective effect against HPV35 was comparable to those of the HPV35 VLP alone, the mixed HPV16/HPV35 VLP, and was significantly higher than that of the HPV16N30 VLP alone. This indicated that the H16N30-35T4 VLP could be used as an effective vaccine against HPV16 infection and HPV35 infection, and could be used in place of the mixed vaccine containing HPV16 VLP and HPV35 VLP.
Table 4. Immunization protocols
Immunization antigenAdjuvantImmunization doseNumberImmunization protocol (week)
H16N30-35T1 VLP Aluminum adjuvant 5µg 5 0, 2, 4
H16N30-35T2 VLP Aluminum adjuvant 5µg 5 0, 2, 4
H16N30-35T3 VLP Aluminum adjuvant 5µg 5 0, 2, 4
H16N30-35T4 VLP Aluminum adjuvant 5µg 5 0, 2, 4
H16N30-35T5 VLP Aluminum adjuvant 5µg 5 0, 2, 4
HPV16N30 VLP Aluminum adjuvant 5µg 5 0, 2, 4
HPV35 VLP Aluminum adjuvant 5µg 5 0, 2, 4
HPV16/HPV35 VLP Aluminum adjuvant 5µg for each VLP 5 0, 2, 4


[0095] In addition, the above-prepared H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP, H16N30-35T4-31S3 VLP, H16N30-35T4-31S5 VLP, HPV16N30 VLP, HPV31 VLP, HPV35 VLP, as well as the mixed HPV16/HPV35/HPV31 (i.e., a mixture of HPV16N30 VLP, HPV35 VLP and HPV31 VLP) were adsorbed onto aluminum adjuvant, respectively. Mice were divided into 8 groups according to different immunogens, and each group contained 5 mice. The immunization procedure was: primary immunization was carried out at the 0th week; booster immunizations were carried out at the 2nd and 4th weeks respectively. The immunization method was intraperitoneal injection, and the immunogens and doses used were as shown in Table 5. At the 8th week after the primary immunization, venous blood was collected from eyeball, and the serum was separated, and then the titers of the neutralizing antibodies in the serum were measured. The test results were shown in FIG. 7B. The results showed that the H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP and H16N30-35T4-31S3 VLPs induced high-titer neutralizing antibodies against HPV16, HPV35 and HPV31 in mice; and their protection effects against HPV16 were comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and were significantly higher than those of the HPV35 VLP alone and the HPV31 VLP alone; and their protective effects against HPV35 were comparable to those of the HPV35 VLP alone, the mixed HPV16/HPV35/HPV31 VLP, and were significantly higher than those of the HPV16N30 VLP alone and the HPV31 VLP alone; and their protection effects against HPV31 were comparable to those of the HPV31 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and were significantly higher than those of the HPV16N30 VLP alone and the HPV35 VLP alone. This indicated that the H16N30-35T4-31S1 VLP, H16N30-35T4-31S2 VLP and H16N30-35T4-31S3 VLP could be used as effective vaccines against HPV16 infection, HPV35 infection and HPV31 infection, and could be used in place of the mixed vaccine containing HPV16 VLP, HPV35 VLP and HPV31 VLP.
Table 5. Immunization protocols
Immunization antigenAdjuvantImmunization doseNumberImmunization protocol (week)
H16N30-35T4-31S1 VLP aluminum adjuvant 5µg 5 0, 2, 4
H16N30-35T4-31S2 VLP aluminum adjuvant 5µg 5 0, 2, 4
H16N30-35T4-31S3 VLP aluminum adjuvant 5µg 5 0, 2, 4
H16N30-35T4-31S5 VLP aluminum adjuvant 5µg 5 0, 2, 4
HPV16N30 VLP aluminum adjuvant 5µg 5 0, 2, 4
HPV31 VLP aluminum adjuvant 5µg 5 0, 2, 4
HPV35 VLP aluminum adjuvant 5µg 5 0, 2, 4
HPV16/HPV35/HPV31 VLP aluminum adjuvant 5µg for each VLP 5 0, 2, 4

Example 5: Evaluation 2 of immunoprotection of virus-like particles in animals


ED50 of H16N30-35T4 VLP



[0096] Six weeks old BalB/c female mice (8 mice) were immunized with aluminum adjuvant by single intraperitoneal injection, in which the experimental groups were administered with the H16N30-35T4 VLP (immunization doses were 0.300 µg, 0.100 µg, 0.033 µg, 0.011 µg, and 0.004 µg), the control groups were administered with the HPV16N30 VLP alone and the HPV35 VLP alone (immunization doses were 0.300 µg, 0.100 µg, 0.033 µg, 0.011 µg, 0.004 µg), or the mixed HPV16/HPV35 VLP (immunization doses for each VLP were 0.300 µg, 0.100 µg, 0.033 µg, 0.011 µg, 0.004 µg); and the immunization volume was 1 mL. In the 5th week after immunization, venous blood was collected from eyeball and the HPV antibodies in the blood were detected. ED50 for inducing seroconversion (i.e. inducing the generation of antibodies in mice) was calculated for each sample, by Reed-Muench method (Reed LJ MH. A simple method of estimating fifty percent endpoints. Am J Hyg. 1938; 27:493-7). The results were shown in Tables 6-9.
Table 6. ED50 values of HPV16N30 VLP for inducing the generation of anti-HPV16 and anti-HPV35 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 8 100.00%  
  0.100 8 8 100.00%  
HPV16 0.033 8 5 72.73% 0.019
  0.011 8 3 27.27%  
  0.004 8 0 0.00%  
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV35 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
Table 7. ED50 values of HPV35 VLP for inducing the generation of anti-HPV16 and anti-HPV35 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV16 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
  0.300 8 5 70.00%  
  0.100 8 2 18.18%  
HPV35 0.033 8 0 0.00% 0.196
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
Table 8. ED50 values of the mixed HPV16/HPV35 VLP for inducing the generation of anti-HPV16 and anti-HPV35 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 7 95.65%  
  0.100 8 8 93.75%  
HPV16 0.033 8 6 70.00% 0.023
  0.011 8 1 9.09%  
  0.004 8 0 0.00%  
  0.300 8 8 100.00%  
  0.100 8 8 100.00%  
HPV35 0.033 8 3 37.50% 0.042
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
Table 9. ED50 values of H16N30-35T4 VLP for inducing the generation of anti-HPV16 and anti-HPV35 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 7 92.86%  
  0.100 8 5 60.00%  
HPV16 0.033 8 1 8.33% 0.081
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
  0.300 8 5 100.00%  
  0.100 8 1 100.00%  
HPV35 0.033 8 0 22.22% 0.264
  0.011 8 0 6.67%  
  0.004 8 0 0.00%  


[0097] The results showed that after 5 weeks of immunization in mice, the EDso of the H16N30-35T4 VLP for inducing the generation of anti-HPV16 antibody in mice was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35 VLP, and was significantly better than that of the HPV35 VLP alone; and the EDso thereof for inducing the generation of anti-HPV35 antibody in mice was comparable to those of the HPV35 VLP alone and the mixed HPV16/HPV35 VLP, and was significantly better than that of the HPV16N30 VLP alone. This indicated that the H16N30-35T4 VLP had good cross-immunogenicity and cross-protection against HPV16 and HPV35.

ED50 of H16N30-35T4-31S3 VLP



[0098] Six weeks old BalB/c female mice (8 mice) were immunized with aluminum adjuvant by single intraperitoneal injection. The experimental groups were administered with the H16N30-35T4-31S3 VL (immunization doses were 0.300 µg, 0.100 µg, 0.033 µg, 0.011 µg, 0.004 µg); the control groups were administered with the HPV16N30 VLP alone, the HPV35 VLP alone, the HPV31 VLP alone (immunization doses were 0.300 µg, 0.100 µg, 0.033 µg, 0.011 µg, 0.004 µg), and the mixed HPV16/HPV35 /HPV31 VLP (immunization doses of each VLP were 0.300 µg, 0.100 µg, 0.033 µg, 0.011 µg, 0.004 µg); and the immunological volume was 1 mL. In the 5th week after immunization, venous blood was collected from eyeball and the HPV antibodies in the blood were detected. ED50 for inducing seroconversion (i.e. inducing the generation of antibodies in mice) was calculated for each sample, by Reed-Muench method (Reed LJ MH. A simple method of estimating fifty percent endpoints. Am J Hyg. 1938; 27:493-7). The results were shown in Tables 10-14.
Table 10. ED50 values of HPV16N30 VLP for inducing the generation of anti-HPV16, anti-HPV35 and anti-HPV31 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 7 96.67%  
  0.100 8 8 95.65%  
HPV16 0.033 8 8 93.33% 0.008
  0.011 8 6 66.67%  
  0.004 8 0 0.00%  
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV35 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV31 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
Table 11. ED50 values of HPV35 VLP for inducing the generation of anti-HPV16, anti-HPV35 and anti-HPV31 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV16 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
  0.300 8 8 100.00%  
  0.100 8 8 100.00% 0.017
HPV35 0.033 8 7 90.00%  
  0.011 8 2 22.22%  
  0.004 8 0 0.00%  
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV31 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
Table 12. ED50 values of HPV31 VLP for inducing the generation of anti-HPV16, anti-HPV35 and anti-HPV31 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV16 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
  0.300 8 0 0.00%  
  0.100 8 0 0.00%  
HPV35 0.033 8 0 0.00% >0.3
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  
  0.300 8 8 100.00%  
  0.100 8 8 100.00%  
HPV31 0.033 8 7 91.67% 0.014
  0.011 8 3 40.00%  
  0.004 8 1 7.14%  
Table 13. ED50 values of the mixed HPV16/HPV35/HPV31 VLP for inducing the generation of anti-HPV16, anti-HPV35 and anti-HPV31 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 for each VLP 8 7 95.24%  
  0.100 for each VLP 8 5 76.47%  
HPV16 0.033 for each VLP 8 1 42.11% 0.043
  0.011 for each VLP 8 5 33.33%  
  0.004 for each VLP 8 2 9.09%  
  0.300 for each VLP 8 8 100.00%  
  0.100 for each VLP 8 8 100.00%  
HPV35 0.033 for each VLP 8 8 100.00% 0.011
  0.011 for each VLP 8 4 50.00%  
  0.004 for each VLP 8 0 0.00%  
  0.300 for each VLP 8 8 100.00%  
  0.100 for each VLP 8 8 100.00%  
HPV31 0.033 for each VLP 8 8 100.00% 0.006
  0.011 for each VLP 8 7 88.89%  
  0.004 for each VLP 8 1 11.11%  
Table 14. ED50 values of H16N30-35T4-31S3 VLP for inducing the generation of anti-HPV16, anti-HPV35 and anti-HPV31 antibodies in mice
TypeDose (µg)Number of mice (mice)Seroconversion number (mice)Seroconversion rateED50 (µg)
  0.300 8 8 100.00%  
  0.100 8 7 94.44%  
HPV16 0.033 8 7 83.33% 0.017
  0.011 8 3 30.00%  
  0.004 8 0 0.00%  
  0.900 8 6 86.67%  
  0.300 8 3 50.00%  
HPV35 0.033 8 1 22.22% 0.100
  0.011 8 3 13.64%  
  0.004 8 0 0.00%  
  0.900 8 5 80.00%  
  0.100 8 2 43.75%  
HPV31 0.033 8 5 29.41% 0.121
  0.011 8 0 0.00%  
  0.004 8 0 0.00%  


[0099] The results showed that after 5 weeks of immunization in mice, the ED50 of H16N30-35T4-31S3 VLP for inducing the generation of anti-HPV16 antibody in mice was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and was significantly better than those of the HPV35 VLP alone and the HPV31 VLP alone; and the ED50 thereof for inducing the generation of anti-HPV35 antibody in mice was comparable to those of the HPV35 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and was significantly better than those of the HPV16N30 VLP alone and the HPV31 VLP alone; the ED50 thereof for inducing the generation of anti-HPV31 antibody in mice was comparable to those of the HPV31 VLP alone and the mixed HPV16/HPV35/HPV31 VLP, and was significantly better than those of the HPV16N30 VLP alone and the HPV35 VLP alone. This indicated that the H16N30-35T4-31S3 VLP had good cross-immunogenicity and cross-protection against HPV16, HPV35 and HPV31.

Evaluation of titers of neutralizing antibodies in serum after immunization with H16N30-35T4 VLP in mice



[0100] In this experiment, the immunization protocols were shown in Table 15. All mice (6-weeks old BalB/c female mice) were divided into 3 groups: 10 µg dose group (immunization dose was 10 µg, using aluminum adjuvant), 1 µg dose group (immunization dose was 1 µg, using aluminum adjuvant), and 0.1 µg dose group (immunization dose was 0.1 µg, using aluminum adjuvant). Each group was subdivided into 4 subgroups, in which the control subgroups 1 and 2 were immunized with the HPV16N30 VLP alone and the HPV35 VLP alone respectively, the control subgroup 3 was immunized with the mixed HPV16/HPV35 VLP, and the experimental subgroup was immunized with H16N30-35T4 VLP.

[0101] Six mice per subgroup were immunized by intraperitoneal injection, and the immunization doses were 10 µg, 1 µg, and 0.1 µg, respectively, and the injection volume was 1 ml. All mice were immunized initially at the 0th week, and boosted at the 2nd and 4th weeks, respectively. Blood samples were collected from the mice via orbital bleeding at the 8th week, and the titers of antibodies against HPV16 and HPV35 in the serum were analyzed. The results of the analysis were shown in FIGs. 8A-8C. The results showed that the H16N30-35T4 VLP induced high titers of neutralizing antibodies against HPV16 in mice, and its protective effect was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35 VLP at the same dose, and was significantly better than that of the HPV35 VLP alone at the same dose; and it induced high titers of neutralizing antibodies against HPV35 in mice, and its protective effect was comparable to those of the HPV35 VLP alone and the mixed HPV16/HPV35 VLP at the same dose, and was significantly better than that of the HPV16N30 VLP alone at the same dose. This indicated that the H16N30-35T4 VLP had good cross-immunogenicity and cross-protection against HPV16 and HPV35.
Table 15. Immunization protocols
GroupImmunization antigenAdjuvantImmunization doseNumberImmunization protocol (week)
10µg dose group HPV16N30 VLP Aluminum adjuvant 10µg 6 0, 2, 4
HPV35 VLP Aluminum adjuvant 10µg 6 0, 2, 4
HPV16/HPV35 VLP Aluminum adjuvant 10µg for each VLP 6 0, 2, 4
H16N30-35T4 VLP Aluminum adjuvant 10µg 6 0, 2, 4
1µg dose group HPV16N30 VLP Aluminum adjuvant 1µg 6 0, 2, 4
HPV35 VLP Aluminum adjuvant 1µg 6 0, 2, 4
HPV16/HPV35 VLP Aluminum adjuvant 1µg for each VLP 6 0, 2, 4
H16N30-35T4 VLP Aluminum adjuvant 1µg 6 0, 2, 4
0.1µg dose group HPV16N30 VLP Aluminum adjuvant 0.1µg 6 0, 2, 4
HPV35 VLP Aluminum adjuvant 0.1µg 6 0, 2, 4
  HPV16/HPV35 VLP Aluminum adjuvant 0.1µg for each VLP 6 0, 2, 4
H16N30-35T4 VLP Aluminum adjuvant 0.1µg 6 0, 2, 4

Evaluation of titers of neutralizing antibodies in serum after immunization with H16N30-35T4-31S3 VLP in mice



[0102] In this experiment, the immunization protocols were shown in Table 16. All mice (6-weeks old BalB/c female mice) were divided into 3 groups: 10 µg dose group (immunization dose was 10 µg, using aluminum adjuvant), 1 µg dose group (immunization dose was 1 µg, using aluminum adjuvant), and 0.1 µg dose group (immunization dose was 0.1 µg, using aluminum adjuvant). Each group was subdivided into 6 subgroups, in which the control subgroups 1, 2, and 3 were immunized with the HPV16N30 VLP alone, the HPV35 VLP alone and the HPV31 VLP alone, respectively, the control subgroup 4 was immunized with the mixed HPV16/HPV35/HPV31 VLP, and the experimental subgroup was immunized with H16N30-35T4-31S3 VLP alone.

[0103] Six mice per subgroup were immunized by intraperitoneal injection, and the immunization doses were 10 µg, 1 µg, 0.1 µg, and the injection volume was 1 ml. All mice were immunized initially at the 0th week, and boosted at the 2nd and 4th weeks, respectively. Blood samples were collected from the mice via orbital bleeding at the 8th week, and the titers of antibodies against HPV16, HPV35 and HPV31 in the serum were analyzed. The results of the analysis were shown in FIGs. 8D-8F. The results showed that the H16N30-35T4-31S3 VLP induced high titers of neutralizing antibodies against HPV16 in mice, and its protective effect was comparable to those of the HPV16N30 VLP alone and the mixed HPV16/HPV35/HPV31 VLP at the same dose, and was significantly better than that of the HPV35 VLP alone or the HPV31 VLP alone at the same dose; and it induced high titers of neutralizing antibodies against HPV35 in mice, and its protective effect was comparable to those of the HPV35 VLP alone and the mixed HPV16/HPV35/HPV31 VLP at the same dose, and was significantly better than that of the HPV16N30 VLP alone or the HPV31 VLP alone at the same dose; and it induced high titers of neutralizing antibodies against HPV31 in mice, and its protection effect was comparable to those of the HPV31 VLP alone and the mixed HPV16/HPV35/HPV31 VLP at the same dose, and significantly better than that of the HPV16N30 VLP alone or the HPV35 VLP alone at the same dose. This indicated that the H16N30-35T4-31S3 VLP had good cross-immunogenicity and cross-protection against HPV16, HPV35 and HPV31.
Table 16. Immunization protocols
GroupImmunization antigenAdjuvantImmunization doseNumberImmunizatio n protocol (week)
10µg dose group HPV16N30 VLP aluminum adjuvant 10µg 6 0, 2, 4
HPV35 VLP aluminum adjuvant 10µg 6 0, 2, 4
HPV31 VLP aluminum adjuvant 10µg 6 0, 2, 4
HPV16/HPV35/HPV31 VLP aluminum adjuvant 10µg for each VLP 6 0, 2, 4
H16N30-35T4-31S3 VLP aluminum adjuvant 10µg 6 0, 2, 4
1µg dose group HPV16N30 VLP aluminum adjuvant 1µg 6 0, 2, 4
HPV35 VLP aluminum adjuvant 1µg 6 0, 2, 4
HPV31 VLP aluminum adjuvant 1µg 6 0, 2, 4
HPV16/HPV35/HPV31 VLP aluminum adjuvant 1µg for each VLP 6 0, 2, 4
H16N30-35T4-31S3 VLP aluminum adjuvant 1µg 6 0, 2, 4
0.1µg dose group HPV16N30 VLP aluminum adjuvant 0.1µg 6 0, 2, 4
HPV35 VLP aluminum adjuvant 0.1µg 6 0, 2, 4
HPV31VLP aluminum adjuvant 0.1µg 6 0, 2, 4
HPV16/HPV35/HPV31 VLP aluminum 0.1µg for each 6 0, 2, 4
    adjuvant VLP    
H16N30-35T4-31S3 VLP aluminum adjuvant 0.1µg 6 0, 2, 4


[0104] Although specific embodiments of the invention have been described in detail, a person skilled in the art will appreciate that various modifications and alterations of the details of the invention can be made in light of the teachings of all disclosures, and all these modifications and alterations fall within the scope of the invention. The full scope of the invention is given by the appended claims and any equivalents thereof.






























































































Claims

1. A mutated HPV16 L1 protein or a variant thereof, wherein the mutated HPV16 L1 protein has the following mutations compared to a wild-type HPV16 L1 protein:

(1) a N-terminal truncation of 4-50 amino acids, such as 4, 6, 8, 10, 20, 30 or 40 amino acids; and

(2) a substitution of amino acid residues at positions 292-316 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a second type of wild-type HPV;

optionally, the mutated HPV16 L1 protein further has the following mutation:

(3) a substitution of amino acid residues at positions 76-87 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a third type of wild-type HPV;

(4) a substitution of amino acid residues at positions 152-167 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a third type of wild-type HPV; or,

(5) a substitution of amino acid residues at positions 202-207 of the wild-type HPV16 L1 protein with amino acid residues at the corresponding positions of a L1 protein of a third type of wild-type HPV;
and, the variant differs from the mutated HPV16 L1 protein only by substitution (preferably conservative substitution), addition or deletion of one or several (e.g., 1, 2, 3, 4, 5, 6, 7, 8, or 9) amino acids, and maintains the function of the mutated HPV16 L1 protein, i.e., an ability of inducing neutralizing antibodies against at least two types of HPV (e.g., HPV16 and HPV35, or HPV16, HPV35 and HPV31);
preferably, the mutated HPV16 L1 protein has a N-terminal truncation of 30 or 40 amino acids compared to the wild-type HPV16 L1 protein;
preferably, the mutated HPV16 L1 protein has a N-terminal truncation of 30 amino acids compared to the wild-type HPV16 L1 protein;
preferably, the second type of wild-type HPV is HPV35; preferably, the amino acid residues at the corresponding positions described in (2) are the amino acid residues at positions 266-288 of the wild-type HPV35 L1 protein;
preferably, the third type of wild-type HPV is HPV31; preferably, the amino acid residues at the corresponding positions described in (3) are the amino acid residues at positions 50-62 of the wild-type HPV31 L1 protein; preferably the amino acid residues at the corresponding positions described in (4) are the amino acid residues at positions 127-142 of the wild-type HPV31 L1 protein; preferably, the amino acid residues at the corresponding positions described in (5) are the amino acid residues at positions 177-182 of the wild-type HPV31 L1 protein;
preferably, the wild-type HPV16 L1 protein has an amino acid sequence set forth in SEQ ID NO: 1;
preferably, the wild-type HPV35 L1 protein has an amino acid sequence set forth in SEQ ID NO: 2;
preferably, the wild-type HPV31 L1 protein has an amino acid sequence set forth in SEQ ID NO: 3;
preferably, the mutated HPV16 L1 protein has an amino acid sequence selected from the group consisting of SEQ ID NOs: 7, 9, 10, 11.


 
2. An isolated nucleic acid, which encodes the mutated HPV16 L1 protein or a variant thereof according to Claim 1.
 
3. A vector comprising the isolated nucleic acid according to Claim 2.
 
4. A host cell comprising the isolated nucleic acid according to Claim 2 and/or the vector according to Claim 3.
 
5. A HPV virus-like particle, which comprises or consists of the mutated HPV16 L1 protein or a variant thereof according to Claim 1.
 
6. A composition, which comprises the mutated HPV16 L1 protein or a variant thereof according to Claim 1, or the isolated nucleic acid according to Claim 2, or the vector according to Claim 3, or the host cell according to Claim 4, or the HPV virus-like particle according to Claim 5.
 
7. A pharmaceutical composition or vaccine, which comprises the HPV virus-like particle according to Claim 5, and optionally further comprises a pharmaceutically acceptable carrier and/or excipient;
preferably, the HPV virus-like particle is present in an amount effective for preventing HPV infection or a disease caused by HPV infection;
preferably, the HPV infection is infection by one or more HPV types (e.g., HPV 16 infection, HPV 35 infection, and/or HPV 31 infection);
preferably, the disease caused by HPV infection is selected from the group consisting of cervical cancer and condyloma acuminatum.
 
8. A method for preparing the mutated HPV16 L1 protein or a variant thereof according to Claim 1, which comprises expressing the mutated HPV16 L1 protein or a variant thereof in a host cell, and then recovering the mutated HPV16 L1 protein or a variant thereof from a culture of the host cell;
preferably, the host cell is E. coli;
preferably, the method comprises the steps of: expressing the mutated HPV16 L1 protein or a variant thereof in E. coli, and then obtaining the mutated HPV16 L1 protein or a variant thereof by purifying a lysate supernatant of the E. coli; preferably, the mutated HPV16 L1 protein or variant thereof is recovered from the lysate supernatant of the E. coli by chromatography (e.g., cation exchange chromatography, hydroxyapatite chromatography, and/or hydrophobic interaction chromatography).
 
9. A method for preparing a vaccine, which comprises combining the HPV virus-like particle according to Claim 5 with a pharmaceutically acceptable carrier and/or excipient.
 
10. A method for preventing HPV infection or a disease caused by HPV infection, which comprises administering to a subject a prophylactically effective amount of the HPV virus-like particle according to Claim 5 or the pharmaceutical composition or vaccine according to Claim 7;
preferably, the HPV infection is infection by one or more HPV types (e.g., HPV 16 infection, HPV 35 infection, and/or HPV 31 infection);
preferably, the disease caused by HPV infection is selected from the group consisting of cervical cancer and condyloma acuminatum.
 
11. A use of the mutated HPV16 L1 protein or a variant thereof according to Claim 1 or the HPV virus-like particle according to Claim 5 in the manufacture of a pharmaceutical composition or vaccine for preventing HPV infection or a disease caused by HPV infection;
preferably, the HPV infection is infection by one or more HPV types (e.g., HPV 16 infection, HPV 35 infection, and/or HPV 31 infection);
preferably, the disease caused by HPV infection is selected from the group consisting of cervical cancer and condyloma acuminatum.
 




Drawing























































REFERENCES CITED IN THE DESCRIPTION



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Non-patent literature cited in the description