CHLAMYDIA TRACHOMATIS ANTIGENIC POLYPEPTIDES AND USES THEREOF FOR VACCINE PURPOSES

Abstract

Chlamydiae are intracellular bacterial pathogens responsible for a variety of infections. The inventors have set up candidate vaccines against Chlamydia trachomatis. In particular, the inventors have identified specific epitopes to be included in vaccine candidates thanks to in silico analysis of the amino-acid sequence of these proteins to map predicted MHC-I and -II epitopes by online software (NetMHC-4.0 and NetMHCII-2.3) and peptide binding prediction software. B cell epitopes were also mapped using online software (BepiPred-2.0 and Discotope). Finally, the inventors have generated some specific CD40 or Langerin antibodies comprising one or more identified epitope(s) of the present invention and that are suitable for vaccine purposes. Therefore, the present invention relates to Chlamydia trachomatis (Ct) antigenic polypeptides and uses thereof for vaccine purposes.

Claims

1.-33. (canceled)

34. A Chlamydia trachomatis (Ct) antigenic polypeptide that comprises: a VS4 bis polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:2, or a YchM polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:3, or a PgP3 polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:4, or a PmPG polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:5, or an NqrC polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID N0:6.

35. A Ct antigenic fusion protein that comprises one or more Ct antigenic polypeptide(s) selected from: a VS4 bis polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:2, a YchM polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:3, a PgP3 polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:4, a PmPG polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:5, and a NqrC polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:6, optionally fused to each other directly or via a linker selected from the group consisting of FlexV1, f1, f2, f3, or f4.

36. The Ct antigenic fusion protein of claim 35 that has the formula of (Ag-L)n wherein Ag represents a Ct antigenic polypeptide that comprises: a VS4 bis polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:2, or a YchM polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:3, or a PgP3 polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:4, or a PmPG polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:5, or an NqrC polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:6, L represents a linker, and n represents an integer number from 1 to 5.

37. The Ct antigenic fusion protein of claim 35 that comprises in said order the VS4 bis antigenic polypeptide, the PmpG antigenic polypeptide, the PgP3 antigenic polypeptide, the YchM antigenic polypeptide, and the NqrC antigenic polypeptide.

38. The Ct antigenic fusion protein of claim 35 that has the formula of VS4 bis-f1-PmpG-f2-PgP3-f3-YchM-f4-NqrC and that consists of the amino acid sequence as set forth in SEQ ID NO:12.

39. An antibody that is directed against a surface antigen of an antigen presenting cell wherein the heavy chain and/or the light chain is conjugated or fused to the Ct antigenic fusion protein of claim 35.

40. The antibody of claim 39, wherein the heavy chain of the antibody and/or the light chain of the antibody is conjugated or fused to a Ct antigenic fusion protein that comprises one or more Ct antigenic polypeptide(s) selected from: a VS4 bis polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:2, a YchM polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:3, a PgP3 polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:4, a PmPG polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:5, and a NqrC polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:6, optionally fused to each other directly or via a linker selected from the group consisting of FlexV1, f1, f2, f3, or f4.

41. The antibody of claim 39 that is an IgG antibody.

42. The antibody of claim 39 that is specific for CD40, and wherein the antibody derives from the 12E12 antibody and comprises: (a) a heavy chain comprising the complementarity determining regions CDR1H, CDR2H and CDR3H, the CDR1H having the amino acid sequence GFTFSDYYMY (SEQ ID NO:13), the CDR2H having the amino acid sequence YINSGGGSTYYPDTVKG (SEQ ID NO:14), and the CDR3H having the amino acid sequence RGLPFHAMDY (SEQ ID NO:15), (b) and a light chain comprising the complementarity determining regions CDR1L, CDR2L and CDR3L, the CDR1L having the amino acid sequence SASQGISNYLN (SEQ ID NO:16) the CDR2L having the amino acid sequence YTSILHS (SEQ ID NO:17) and the CDR3L having the amino acid sequence QQFNKLPPT (SEQ ID NO:18) or derives from the 11B6 antibody and comprises: (c) a heavy chain comprising the complementarity determining regions CDR1H, CDR2H and CDR3H, the CDR1H having the amino acid sequence GYSFTGYYMH (SEQ ID NO:19), the CDR2H having the amino acid sequence RINPYNGATSYNQNFKD (SEQ ID NO:20), and the CDR3H having the amino acid sequence EDYVY (SEQ ID NO:21), and (d) a light chain comprising the complementarity determining regions CDR1L, CDR2L and CDR3L, the CDR1L having the amino acid sequence RSSQSLVHSNGNTYLH (SEQ ID NO:22) the CDR2L having the amino acid sequence KVSNRFS (SEQ ID NO:23) and the CDR3L having the amino acid sequence SQSTHVPWT (SEQ ID NO:24) or derives from the 12B4 antibody and comprises: (e) a heavy chain comprising the complementarity determining regions CDR1H, CDR2H and CDR3H, the CDR1H having the amino acid sequence GYTFTDYVLH (SEQ ID NO:25), the CDR2H having the amino acid sequence YINPYNDGTKYNEKFKG (SEQ ID NO:26), and the CDR3H having the amino acid sequence GYPAYSGYAMDY (SEQ ID NO:27), and (f) a light chain comprising the complementarity determining regions CDR1L, CDR2L and CDR3L, the CDR1L having the amino acid sequence RASQDISNYLN (SEQ ID NO:28) the CDR2L having the amino acid sequence YTSRLHS (SEQ ID N0:29) and the CDR3L having the amino acid sequence HHGNTLPWT (SEQ ID NO:30).

43. The antibody of claim 39 that is a CD40 agonist antibody whose heavy chain or the light chain (i.e., the chain that is not conjugated or fused to the Ct antigenic fusion protein) is conjugated or fused to a CD40 binding domain of CD40L (SEQ ID NO:1).

44. The antibody of claim 39 that is a CD40 agonist antibody whose heavy chain or the light chain (i.e., the chain that is not conjugated or fused to the Ct antigenic fusion protein) is conjugated or fused to a CD40 binding domain of CD40L (SEQ ID NO:1), wherein: the CD40 binding domain of CD40L is fused to the C-terminus of a light or heavy chain of said CD40 agonist antibody, optionally via a linker, or the heavy chain of the antibody is fused or conjugated to the Ct antigenic fusion protein and the light chain is conjugated or fused to the CD40 binding domain of CD40L (SEQ ID NO:1).

45. The antibody of claim 39 that is specific for Langerin and that comprises: a heavy chain comprising the complementarity determining regions CDR1H, CDR2H and CDR3H of the 15B10 antibody and a light chain comprising the complementarity determining regions CDR1L, CDR2L and CDR3L of the 15B10 antibody, or a heavy chain comprising the complementarity determining regions CDR1H, CDR2H and CDR3H of the 2G3 antibody and a light chain comprising the complementarity determining regions CDR1L, CDR2L and CDR3L of the 2G3 antibody, or a heavy chain comprising the complementarity determining regions CDR1H, CDR2H and CDR3H of the 4C7 antibody and a light chain comprising the complementarity determining regions CDR1L, CDR2L and CDR3L of the 4C7 antibody.

46. The antibody of claim 39 that comprises a heavy chain or light chain that is conjugated via a dockerin domain to the cohesin fusion protein that consists of the amino acid sequence as set forth in SEQ ID NO:48.

47. The antibody of claim 39, wherein the heavy chain and/or the light chain is fused to a Ct antigenic fusion protein that comprises one or more Ct antigenic polypeptide(s) selected from: a VS4 bis polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:2, a YchM polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:3, a PgP3 polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:4, a PmPG polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:5, and a NqrC polypeptide having an amino acid sequence having at least 80% of identity with the amino acid as set forth in SEQ ID NO:6, optionally fused to each other directly or via a linker selected from the group consisting of FlexV1, f1, f2, f3, or f4 via the linker selected from the group consisting of FlexV1, f1, f2, f3, and f4.

48. A nucleic acid that encodes for the heavy chain and/or the light chain of the antibody of claim 39.

49. A vector comprising the nucleic acid of claim 48.

50. A host cell which has been transfected, infected, or transformed by the nucleic acid of claim 48.

51. A host cell which has been transfected, infected, or transformed by the vector of claim 49.

52. A vaccine composition that comprises one or more antibody(ies) of claim 39.

53. A method for vaccinating a subject in need thereof against Chlamydia trachomatis comprising administering a therapeutically effective amount of one or more antibody(ies) of claim 39.

Description

FIGURES

[0142] FIG. 1. Schematic representation of the first polyepitopic Chlamydia DC vaccine generated. Selected antigens from C. Trachomatis, chosen from the literature and our in silico analyses are fused with the heavy chain of the ?CD40 mAb, while adding flexible spacers to improve their synthesis and/or secretion.

[0143] FIG. 2: In vitro expansion of C. trachomatis Ct-5pp-specific memory T-cells by the ?CD40 vaccine construct. PBMCs of 4 donors were stimulated with the ?CD40 mAb associated with the Ct-5pp antigens or Ebola GP as irrelevant control (EBOV) and were then restimulated at day 9 with pools of peptides overlapping Ct-5pp. The percentages of CD4+ T cells producing any of tested cytokines after 10 days of culture are shown.

EXAMPLE 1

[0144] We have identified specific epitopes to be included in vaccine candidates against Chlamydia trachomatis thanks to in silico analysis of the amino-acid sequence of MOMP VS4, YchM, PgP3, PmPG and NqrC proteins to map predicted MHC-I and -II epitopes by online software and peptide binding prediction software. The five proteins were analysed using NetMHC 4.0 (https://services.healthtech.dtu.dk/service.php?NetMHC-4.0) and NetMHCII 2.3 (https://services.healthtech.dtu.dk/service.php?NetMHCII-2.3), MHC class-I and MHC class-II/peptide binding prediction softwares, respectively. Linear B-cell epitopes were predicted using BepiPred 2.0 (https://services.healthtech.dtu.dk/service.php?BepiPred-2.0). Based on the above mentioned methodology we have identified the following epitopes of interest:

TABLE-US-00008 VS4bis SEQIDNO:2 ASIDYHEWQASLALSYRLNMFTPYIGVKWS YchMantigen SEQIDNO:3 EKPPKIFILCMTRVPTIDASAMHALEEFFL PgP3antigen SEQIDNO:4 GKFTVTPKSSGSMFLVSADIIASRMEGGVV PmPGantigen SEQIDNO:5 PAANQLITLSNLHLSLSSLLANNAVTNPPT NqrCantigen SEQIDNO:6 CNGVTESFSHSLAPYRALLTFFANSKPSGE

EXAMPLE 2

[0145] The polyepitope protein of SEQ ID NO:12 was prepared and conjugated to an anti-CD40 antibody according to FIG. 1. PBMCs from Chlamydia infected individuals were keeping frozen. After thawing, cells are cultured in RPMI supplemented with 10% human serum (SAB, Jacques boys) for overnight resting. Cells were then cultured in the presence of 10 nM of ?CD40.Ct-5pp or irrelevant antigen. Non stimulated or SEB (10 ng/ul) stimulated cells were used as negative and positive controls respectively. At day 2 and 5 of culture, medium was refreshed with supplement of IL-2 (100U/mL). At day 7, medium was renewed and cells kept for resting 24H without any cytokines. On day 8, cells were stimulated in the presence of brefeldin A (5ug/ml) by pools of overlapping peptides covering each antigen of the polyepitopic Chlamydia construct. Cells were subsequently stained for phenotypical markers (CD3, CD4, CD8) and for their intracellular synthesize of cytokines during peptide stimulation (IFNg, TNFa, MIP-1b, IL-2, IL-4, IL-13, IL-10). Fluorescence of PFA-fixed cells was assessed by flow cytometry using BD LSRII flow cytometer. Data were subsequently analyzed by FlowJo software (Tristar). The results are depicted in FIG. 2.

REFERENCES

[0146] Throughout this application, various references describe the state of the art to which this invention pertains. The disclosures of these references are hereby incorporated by reference into the present disclosure.