Patent Application
20110020398
A subject of the present invention is novel peptide compositions and their use in particular in the preparation of pharmaceutical compositions active against the hepatitis C virus.
A subject of the present invention is a peptide composition useful in particular in prophylactic and therapeutic vaccination directed against the hepatitis C virus.
Hepatitis C is the main cause of hepatitis acquired by transfusion. Hepatitis C can also be transmitted by other percutaneous routes, for example by injection of drugs by intravenous route. The risk of contamination to health professionals is moreover not negligible.
Hepatitis C differs from the other forms of liver diseases associated with viruses, such as hepatitis A, B or D. Infections by the hepatitis C virus (HCV) are mostly chronic, resulting in liver diseases, such as hepatitis, cirrhosis and carcinoma in a large number of cases (5 to 20%).
Although the risk of transmission of the virus by transfusion has diminished due to the establishment of screening tests in the 1990s, the frequency of hepatitis C remains high. By way of example, a recent study indicates that today there are still 10,000 to 15,000 new cases of infection per year in France (S. Deuffic et al., Hepatology 1999; 29: 1596-1601). At present, approximately 170 million people world-wide are chronically infected by HCV. Populations at high risk are chiefly hospital staff and intravenous-drug users, but asymptomatic blood donors exist who do not belong to these high-risk groups and in whom circulating anti-HCV antibodies have been found. For the latter, the infection route has not yet been identified.
HCV was the first hepatotropic virus isolated by means of molecular biology techniques. The sequences of the viral genome were cloned before the viral particle was visualized.
HCV belongs to a novel group of the Flaviviridae family, the hepaciviruses. This is a virus with a single positive RNA strand, of 9.5 kb, which is replicated by a copy of complementary RNA and the translation product of which is a precursor of a single polyprotein of approximately 3,000 amino acids. The 5′ end of the HCV genome corresponds to a non-translated region adjacent to the genes which code for the structural proteins, the core protein of the nucleocapsid, the two envelope glycoproteins, E1 and E2, and a small protein called p7. The non-translated 5′ region and the core gene are relatively well preserved in the different genotypes. The envelope proteins E1 and E2 are encoded by more variable regions from one isolate to another. The protein p7 is an extremely hydrophobic protein the function of which is not known. The 3′ end of the HCV genome contains the genes which code for the non-structural proteins (NS2, NS3, NS4, NS5) and for a non-coding 3′ region possessing a well-preserved domain (Major M E, Feinstone S M, Hepatology, June 1997, 25(6): 1527-1538).
Therapy for the treatment of hepatitis C which is the current focus of attention is a dual therapy using pegylated interferon and ribavirin (Maims M P et al., The Lancet, 22 Sep. 2001, Vol. 358, 958-965). Whilst this therapy is particularly effective in the case of patients infected by viral strains belonging to genotypes 2 and 3, it only has a limited effect on genotypes 1a, 1b and 4 (Manns M P, above).
It is therefore necessary to develop a vaccine composition targeting these poorly-responsive genotypes as a priority.
Several studies today show that the control of an infection caused by HCV, either naturally (“spontaneous resolution”), or after treatment (“therapeutic resolution”) is associated with the induction or potentialization of cell-mediated immune responses involving the T-CD4+ and T-CD8+ lymphocytes (CERNY A et al., J. Clin. Invest., 95: 521-530 (1995)).
The object of vaccines based on the use of peptides is generally to induce immune responses mediated by the T-CD4+ and/or T-CD8+ lymphocytes.
The molecules of the major histocompatibility complex (MHC) are described as class I or class II. Class I molecules are expressed on virtually all of the nucleated cells and can be the target of CD8+ cytotoxic T lymphocytes (CTLs). The CTLs recognize the peptides or epitopes which are presented in association with the MHC molecules of class I.
For example, the class I molecule HLA-A2.1 indicates that the binding site of the peptide is created by bringing together the domains α1 and α2 of the heavy chain of class I (Bjorkman et al., Nature, 329: 506 (1987)).
Certain authors have concluded the immunogenic power of peptide preparations on the basis of their good binding scores on HLA molecules, as in the Patent Application WO01/21189.
Such a deduction is not evident and can lead:
The Applicant has now unexpectedly found that a novel peptide composition containing at least two peptides chosen from the A to D peptides had a strong immunogenic power and had an effect on the ability of the cells originating from patients infected by viral strains of genotype 1a, 1b and 4 to induce specific immune responses. These patients preferably, but not limitatively, have an HLA of type HLA-A2.1.
Thus, a subject of the present invention is the peptide compositions comprising at least two compounds chosen from:
in which X1 is Y or H, X2 is A, G or T, X3 is R or L, X4 is A or T, X5 is G or S, X6 is A, T or V, X7 is H or Y and X8 is I, T, M or V,
in which X18 is L or V, X19 is L or F, X20 is G or S, X21 is C or T, X22 is I or V, X23 is I or V, X24 is K, R or T, X25 is Q or E, X26 is V or N, X27 is D, E or C, X28 is V or A, X29 is V, I, E or M, X30 is L or V, X31 is T, K or A, X32 is Q or H, X33 is S or T, X34 is A or G, X35 is T or S, X36 is C or A, X37 is V, I or T, X38 is V or A, X39 is C or M and X40 is Y or F,
in which X47 is L or P, X48 is A or S, X49 is A or S, X50 is A or S, X51 is I or V, X52 is T, S or A, X53 is T or I, X54 is Q, S or G, X55 is N, Q, H, S, Y or T, X56 is L or M, X57 is L or W, X58 is A or S and X59 is L, P or I, and
in which X69 is R or Q, X70 is P or A, X71 is L or F, X72 is F or Y, X73 is D or E, X74 is V or S, X75 is M or R, X76 is Y or H, X77 is D or N, X78 is V or I, X79 is 5, T or K, X80 is T, K, I or N and X81 is L or T,
in which X18 is L or V, X19 is L or F, X20 is G or S, X21 is C or T, X22 is I or V and X23 is I or V, and
in which X52 is T, S or A, X53 is T or I, X54 is Q, S or G and X55 is N, Q, H, S, Y or T,
as well as the pharmaceutical compositions containing them and their use, in particular as vaccine, for the preparation of a medicament intended for the inhibition or prevention of an infection caused by the hepatitis C virus, and as a diagnostic composition.
A particular subject of the invention is a peptide composition as defined above, characterized in that it comprises at least two peptides chosen from the A, B, C, D peptides.
A subject is also the particular A, B, C, D peptides, the nucleotide sequences coding for said peptides and the microorganisms or host cells cotransformed by these vectors.
Finally a subject is the antibodies directed against the compositions of the invention and a process for detection and/or quantification of the hepatitis C virus in a biological sample using said antibodies.
The peptide compositions of the invention, having a strong immunogenic power against the genotypes 1a, 1b and 4 of the hepatitis C virus, therefore contain at least two peptides chosen from the A to D peptides as defined above.
The A peptide is included in the non-structural protein 3 (NS3) between positions 1244 and 1274 of the polyprotein encoded by the HCV virus.
The B peptide is also included in the protein NS3 between positions 1038 and 1082 of the viral polyprotein.
The C peptide is included in the non-structural protein NS4 between positions 1789 and 1821 of said viral polyprotein.
As for the D peptide, it is included in the non-structural protein NS5b between positions 2573 and 2601 of said viral polyprotein.
Of course, by peptide is meant the peptide as such, as well as its homologues having at least 60%, preferably at least 70%, still more preferably at least 80%, better at least 90% and still better 95% homology with the peptide of interest.
The A to D peptides were obtained from the strain HCV-JA (Kato L., et al., (1990), Proc. Natl. Acad. Sci. USA, 87(24), 9524-9528) otherwise called the Shimotohno strain. They contain known epitopes but, as indicated previously, these epitopes do not necessarily have a high binding score.
The binding score is obtained by prediction, using software, of the ability of known or potential epitope sequences (peptide sequences) to bind to the HLA molecule of interest. This score can be included in a range from negative values to the value of approximately 1000 and by high binding score is meant a binding score greater than or equal to 600.
On the other hand, unexpectedly, the combination of the A to D peptides of the invention makes it possible to induce specific cytotoxic T lymphocytes capable of a vigour and effectiveness greater than that obtained with each of the peptides used separately and/or each of the individual epitopes contained in these peptides used alone or in combination as well as stimulating a higher production of γ-interferon.
Moreover, these peptides are capable of inducing specific T lymphocytes having cross-reactivity.
According to one embodiment of the invention, the compositions of the invention contain two peptides according to the following combinations: A and B peptides, A and C peptides, A and D peptides, B and C peptides, B and D peptides and C and D peptides.
The preferred compositions contain the A and B, A and C, B and D, and C and D peptides, the compositions containing the A and B, C and D, and B and D peptides being more preferred.
According to another embodiment, the compositions of the invention contain three peptides according to the following combinations: A, B and D peptides, A, C and D peptides, and B, C and D peptides, the compositions comprising the A, B and C, A, C and D, and B, C and D peptides being particularly preferred.
According to yet another embodiment, the compositions of the invention contain the four A, B, C, D peptides.
The A peptide in the compositions of the invention has at least the amino acid sequence SEQ ID NO: 1 as described above.
According to one embodiment of the invention, the A peptide has at most the 46 amino acids as described in the following sequence SEQ ID NO: 2: SX9X10VPX11X12X1AX2QGYKVX3VLNPSVX4ATLX5FGX6YMSKAX7GX8X13PX14 X15X16X17GV,
in which X1 to X8 are as defined previously, and X9 is T or N, X10 is K or R, X11 is A or V, X12 is A or E, X13 is E or D, X14 is N or S, X15 is I, L or V, X16 is R or S and X17 is T or S.
In this case, the A peptide is situated between positions 1237 and 1282 of the viral polyprotein.
According to yet another embodiment, the A peptide is chosen from the following peptides:
Preferably, the A peptide is chosen from the peptides of sequences SEQ ID NO: 3 to 18, the peptide of sequence SEQ ID NO: 3 being particularly preferred.
The B peptide in the compositions of the invention has at least the amino acid sequence SEQ ID NO: 45 as described above.
According to one embodiment, the B peptide has at most the 63 amino acids as described in the following sequence SEQ ID NO: 46: AX41ITX42YX43X44QTRGX18X19X20X21X22X23TSLTGRDX24NX25X26X27GEX28QX29X30STAX31 X32X33 FLX34X35X36X37NGX38X39WTVX40HGAGX45X46X47
in which X18 to X40 are as defined above and X41 is P, S or H, X42 is A or T, X43 is S, A, T or C, X44 is Q or R, X45 is S, T or A, X46 is K or R and X47 is T or I.
In this case, the B peptide is situated between positions 1027 and 1089 of the viral polyprotein.
According to yet another embodiment the B peptide is chosen from the following peptides:
ii) sequence SEQ ID NO: 119 which corresponds to sequence SEQ ID NO: 46 in which X18 to X40 are as defined for sequence SEQ ID NO: 75 and X41 is P, X42 is A, X43 is A, X44 is Q, X45 is S, X46 is K and X47 is T,
Preferably, the B peptide is chosen from the peptides of sequences SEQ ID NO: 47 to 80, the peptide of sequence SEQ ID NO: 47 being particularly preferred.
The C peptide in the compositions of the invention has at least the amino acid sequence SEQ ID NO: 127 as described previously.
According to one embodiment, the C peptide has at most the 57 amino acids as described in the following sequence SEQ ID NO: 128: NFIX60GX61QYLAX62LSTLPGNX63AX64X65SX47MX48FTX49X50X51TSPLX52X53X54 X55TLX56FNIX57GGWVAX58QX59X66X67X68
in which X47 to X59 are as defined above and X60 is T or S, X61 is I, T or V, X62 is G or A, X63 is P or L, X64 is I or M, X65 is A, V or R, X66 is A or R, X67 is P, A or D and X68 is P, A or S.
In this case, the C peptide is situated between positions 1767 and 1823 of the viral polyprotein.
According to another embodiment, the C peptide is chosen from the following peptides:
Preferably, the C peptide is chosen from the peptides of sequences SEQ ID NO: 129 to 146, the peptide of sequence SEQ ID NO: 129 being particularly preferred.
The D peptide in the compositions of the invention has at least the amino acid sequence SEQ ID NO: 174 as described above.
According to one embodiment of the invention, the D peptide has at most the 44 amino acids as described in the following sequence SEQ ID NO: 175: KGGX69KX70ARX71IVX72PX73LGX74RVCEKX75ALX76X77VX78X79X80X81X82X83X84 VMGX85X86YX87X88Q
in which X69 to X81 are as defined above and X82 is P or A, X83 is Q, L, H, R, K or P, X84 is A, T, V or P, X85 is P, S or A, X86 is S or A, X87 is G or R and X88 is F or C.
In this case, the D peptide is situated between positions 2570 and 2613 of the viral polyprotein.
According to a further embodiment, the D peptide is chosen from the following peptides:
Preferably, the D peptide is chosen from the peptides of sequences SEQ ID NO: 176 to 187, the peptide of sequence SEQ ID NO: 176 being preferred.
The A, B, C or D peptides as defined by the preceding sequences 1 to 212 are novel and also constitute a subject of the invention.
Thus, according to the invention:
the A peptide has at least the amino acid sequence SEQ ID NO: 1 and at most sequence SEQ ID NO: 2; in particular it is chosen from the peptides:
the B peptide has at least the amino acid sequence SEQ ID NO: 45 and at most sequence SEQ ID NO: 46; in particular, the B peptide is chosen from the peptides:
the C peptide has at least the amino acid sequence SEQ ID NO: 127 and at most sequence SEQ ID NO: 128; in particular, the C peptide is chosen from the peptides:
the D peptide has at least the amino acid sequence SEQ ID NO: 174 and at most sequence SEQ ID NO: 175; in particular, the D peptide is chosen from the peptides:
The expression “the A peptide has at least the amino acid sequence SEQ ID NO: 1 and at most sequence SEQ ID NO: 2” signifies that the N-terminal end is delimited by the amino acid situated at one of positions 1 to 8 of SEQ ID NO: 2 and the C-terminal end is delimited by the amino acid situated at one of positions 38 to 46 of SEQ ID NO: 2.
Thus the A peptide has at least the 31 consecutive amino acids of sequence SEQ ID NO: 1 and at most the 46 consecutive amino acids of sequence SEQ ID NO: 2.
Sequence SEQ ID NO: 2 includes the 31 amino acids of sequence SEQ ID NO: 1.
Thus the A peptide of the invention always has at least the 31 amino acids of sequence SEQ ID NO: 1 and at most 15 additional amino acids distributed on both sides of these 31 amino acids within the limit of sequence SEQ ID NO: 2. For example, an A peptide of the invention can comprise 33 amino acids constituted by 31 amino acids of SEQ ID NO: 1 and either 2 N-terminal amino acids, or 2 C-terminal amino acids, or 1 N-terminal amino acid and a C-terminal amino acid.
The expression “the B peptide has at least the amino acid sequence SEQ ID NO: 45 and at most sequence SEQ ID NO: 46” signifies that the N-terminal end is delimited by the amino acid situated at one of positions 1 to 12 of SEQ ID NO: 46 and the C-terminal end is delimited by the amino acid situated at one of positions 56 to 63 of SEQ ID NO: 46.
Thus the B peptide has at least the 45 consecutive amino acids of sequence SEQ ID NO: 45 and at most the 63 consecutive amino acids of sequence SEQ ID NO: 46.
Sequence SEQ ID NO: 46 includes the 45 amino acids of sequence SEQ ID NO: 45.
Thus the B peptide of the invention always has at least the 45 amino acids of sequence SEQ ID NO: 45 and at most 18 additional amino acids distributed on both sides of these 45 amino acids within the limit of sequence SEQ ID NO: 46.
The expression “the C peptide has at least the amino acid sequence SEQ ID NO: 127 and at most sequence SEQ ID NO: 128” signifies that the N-terminal end is delimited by the amino acid situated at one of positions 1 to 23 of SEQ ID NO: 128 and the C-terminal end is delimited by the amino acid situated at one of positions 54 to 57 of SEQ ID NO: 128.
Thus the C peptide has at least the 32 consecutive amino acids of sequence SEQ ID NO: 127 and at most the 57 consecutive amino acids of sequence SEQ ID NO: 128.
Sequence SEQ ID NO: 128 includes the 32 amino acids of sequence SEQ ID NO: 127.
Thus the C peptide of the invention always has at least the 32 amino acids of sequence SEQ ID NO: 127 and at most 25 additional amino acids distributed on both sides of these 32 amino acids within the limit of sequence SEQ ID NO: 128.
The expression “the D peptide has at least the amino acid sequence SEQ ID NO: 174 and at most sequence SEQ ID NO: 175” signifies that the N-terminal end is delimited by the amino acid situated at one of positions 1 to 4 of SEQ ID NO: 175 and the C-terminal end is delimited by the amino acid situated at one of positions 32 to 44 of SEQ ID NO: 175.
Thus the D peptide has at least the 29 consecutive amino acids of sequence SEQ ID NO: 174 and at most the 44 consecutive amino acids of sequence SEQ ID NO: 175.
Sequence SEQ ID NO: 175 includes the 29 amino acids of sequence SEQ ID NO: 174.
Thus the D peptide of the invention always has at least the 29 amino acids of sequence SEQ ID NO: 174 and at most 15 additional amino acids distributed on both sides of these 29 amino acids within the limit of sequence SEQ ID NO: 175.
The B and C peptides contain novel epitopes having a strong immunogenic power.
Another subject of the invention relates to the B′ epitope, contained in the B peptide and situated between positions 1038 and 1047 of the viral polyprotein, which possesses the following amino acid sequence SEQ ID NO: 213: GX18X19X20X21X22X23TSL
in which X18 is L or V, X19 is L or F, X20 is G or S, X21 is C or T, X22 is I or V and X23 is I or V.
According to one embodiment of the invention, the B′ epitope is chosen from the following epitopes:
Preferably, the B′ epitope possesses at least one of the following characteristics:
Another subject of the invention relates to the C′ epitope, contained in the C peptide and situated between positions 1789 and 1821 of the viral polyprotein, which possesses the following amino acid sequence SEQ ID NO: 221: SPLX52X53X54X55TL
in which X52 is T, S or A, X53 is T or I, X54 is Q, S or G and X55 is N, Q, H, S, Y or T.
According to one embodiment of the invention, the C′ epitope is chosen from the following epitopes:
Preferably, the C′ epitope possesses at least one of the following characteristics:
The compositions of the invention, apart from the A to D peptides, can also contain the B′ and C′ epitopes, which constitutes another subject of the invention.
In a preferred embodiment, the peptide composition of the present invention comprises at least two peptides as defined above which are fused each other.
The present invention also relates to a novel fusion peptide comprising at least two peptides as defined above which are fused each other. The term “fusion” as used herein means that the amino acids of the first peptide and of the second peptide are fused in one polypeptide chain, preferably by in frame fusion of the corresponding coding nucleotide sequences. Advantageously, the fusion peptide of the invention comprises a fusion of at least two peptides chosen from the group consisting of A, B, C, D, B′ and C′ peptides as defined above, as well as pharmaceutical compositions containing such a fusion peptide and its use in particular as a vaccine, for the preparation of a medicament intended for the inhibition or prevention of an infection caused by the hepatitis C virus, and as a diagnostic composition.
A preferred fusion peptide comprises a fusion of at least four peptides chosen from the group consisting of A, B, C, and D peptides. A more preferred peptide composition comprises a fusion of A to D peptides with B peptide located at the N-terminus which is fused to A peptide which is fused to C peptide which is fused to D peptide (B/A/C/D fusion peptide). In particular, the A peptide comprised in the fusion peptide of the invention has at least SEQ ID NO: 3 and at most SEQ ID NO: 19. Independently or in combination with the other peptides, the B peptide comprised in the fusion peptide of the invention has at least SEQ ID NO: 47 and at most SEQ ID NO: 81. Independently or in combination with the other peptides, the C peptide comprised in the fusion peptide of the invention has at least SEQ ID NO: 129 and at most SEQ ID NO: 147, SEQ ID NO: 153, SEQ ID NO: 162 or SEQ ID NO: 167. Independently or in combination with the other peptides, the D peptide comprised in the fusion peptide of the invention has at least SEQ ID NO: 176 and at most SEQ ID NO: 188, SEQ ID NO: 192, SEQ ID NO: 193 or SEQ ID NO: 194, SEQ ID NO: 201, SEQ ID NO: 202, SEQ ID NO: 203, SEQ ID NO: 204, SEQ ID NO: 205 or SEQ ID NO: 210. In a preferred embodiment, the A peptide comprised in the fusion peptide of the invention has the amino acid sequence defined in SEQ ID NO: 3, the B peptide comprised in the fusion peptide of the invention has the amino acid sequence defined in SEQ ID NO: 47, the C peptide comprised in the fusion peptide of the invention has the amino acid sequence defined in SEQ ID NO: 129 and the D peptide comprised in the fusion peptide of the invention has the amino acid sequence defined in SEQ ID NO: 176. Even more preferably, the fusion peptide of the invention comprises the amino acid sequence defined in SEQ ID NO: 234.
The present invention also relates to the nucleotide sequences coding for any one of the A to D peptides as defined by sequences SEQ ID NO: 1 to 212 and B′ and C′ epitopes as defined by sequences SEQ ID NO: 213 to 232 and any one of the fusion peptides as defined above, with a special preference for the fusion peptide comprises the amino acid sequence defined by SEQ ID NO: 234.
The peptides of the invention can be obtained by the genetic engineering technique which comprises the stages of:
This technique is well known to a person skilled in the art. For more details concerning this, reference can be made to the following work: Recombinant DNA Technology I, Editors Ales Prokop, Raskesh K Bajpai; Annals of the New York Academy of Sciences, Volume 646, 1991.
The peptides of the invention can also be prepared by the standard peptide syntheses well known to a person skilled in the art.
The nucleotide sequences according to the invention can be prepared by chemical synthesis and genetic engineering using the techniques well known to a person skilled in the art and described for example in Sambrook J. et al., Molecular Cloning: A Laboratory Manual, 1989.
The nucleotide sequences of the invention can be inserted into expression vectors in order to obtain the compositions or peptides of the invention.
Thus, another subject of the invention is the expression vectors comprising a nucleotide sequence of the invention, as well as the means necessary for its expression. Such means necessary for expression are well known in the art and can vary according to the host cell, the expression vector and the level of expression desired.
As expression vectors, there can be mentioned for example the plasmids, the viral vectors of the vaccine virus type, adenovirus, baculovirus, poxvirus, bacterial vectors of salmonella type, BCG. Such vectors and methods of using and making them are well known in the art (see for example <<Nonviral Vectors for gene Therapy>>, 2001, edited by M. Findeis, Humana Press; <<Adenoviral Vectors for Gene Therapy>>, 2002, edited by Curiel and Douglas, Elsevier Science, Academic Press; and <<Vaccinia Virus and poxyirology>>, 2004, edited by S. Isaacs, Humana Press). The term “viral vector” as used herein encompasses vector DNA as well as viral particles generated thereof by conventional technologies.
In one embodiment, the vector of the invention is an adenoviral vector. It can be derived from a variety of human or animal sources. Any serotype can be employed from the adenovirus serotypes 1 through 51, with a special preference for human adenoviruses 2 (Ad2), 5 (Ad5), 6 (Ad6), 11 (Ad11), 24 (Ad24) and 35 (Ad35). The cited adenoviruses are available from the American Type Culture Collection (ATCC, Rockville, Md.), and have been the subject of numerous publications describing their sequence, organization and methods of producing, allowing the artisan to apply them (see for example U.S. Pat. No. 6,133,028; U.S. Pat. No. 6,110,735; WO02/40665; WO00/50573; EP 1 016 711; Vogels et al., 2003, J. Virol. 77: 8263-8271). Preferably, the adenoviral vector of the invention is replication-defective (see for example WO94/28152; Lusky et al., 1998, J. Virol 72, 2022-2032). Preferred replication-defective adenoviral vectors are E1-defective with an E1 deletion extending from approximately positions 459 to 3328 or from approximately positions 459 to 3510 (by reference to the sequence of the human adenovirus type 5 disclosed in the GeneBank under the accession number M 73260 and in Chroboczek et al., 1992, Virol. 186, 280-285). The cloning capacity can further be improved by deleting additional portion(s) of the adenoviral genome (all or part of the non essential E3 region or of other essential E2, E4 regions). The nucleotide sequence of the present invention can be inserted in any location of the adenoviral genome. Preferably, it is inserted in replacement of the E1 region. It may be positioned in sense or antisense orientation relative to the natural transcriptional direction of the region in question.
In another embodiment the vector of the invention is derived from a poxvirus. It may be obtained from any member of the poxyiridae, in particular canarypox, fowlpox and vaccinia virus, the latter being preferred. Suitable vaccinia viruses include without limitation the Copenhagen strain (Goebel et al., 1990, Virol. 179: 247-266 and 517-563; Johnson et al., 1993, Virol. 196: 381-401), the Wyeth strain and the modified Ankara (MVA) strain (Antoine et al., 1998, Virol. 244: 365-396). The general conditions for constructing recombinant poxvirus are well known in the art (see for example EP 206 920; Mayr et al., 1975, Infection 3: 6-14; Sutter and Moss, 1992, Proc. Natl. Acad. Sci. USA 89: 10847-10851; U.S. Pat. No. 6,440,422). The nucleotide sequence of the present invention is preferably inserted within the poxyiral genome in a non-essential locus. Thymidine kinase gene is particularly appropriate for insertion in Copenhagen vaccinia vectors (Hruby et al., 1983, Proc. Natl. Acad. Sci. USA 80: 3411-3415; Weir et al., 1983, J. Virol. 46: 530-537) and deletion II or III for insertion in MVA vector (Meyer et al., 1991, J. Gen. Virol. 72: 1031-1038; Sutter et al., 1994, Vaccine 12: 1032-1040).
In another embodiment, the expression vector of the invention can be optionally coupled or complexed to conventional drug delivery systems (e.g. lipid or polymer-based liposomes, nanoparticles, etc. such as those described for example in Mahato et al., 1998, Human Gene Ther. 9: 2083-2099 and Allen et al., 2004, Science 303: 18181822).
By “means necessary for the expression” it is meant any means which make it possible to obtain the peptide or fusion peptide of the invention, such as in particular, a promoter, a transcription terminator, a replication origin and preferably a selection marker.
The promoter used in the context of the invention can be of any origin, e.g. viral, cellular or synthetic and be ubiquitous providing constitutive expression or regulable providing for example specific expression in a particular cell type or under specific conditions. It can further be operably linked to an enhancer. Suitable viral promoters include without limitation early promoters obtained from RSV (Rous Sarcoma Virus), SV40 (Simian Virus), and CMV (Cytomegalovirus; Boshart et al., 1985, Cell 41, 521-530), as well as the TK (Thymidine kinase) promoter of HSV-1 virus (Herpes Virus Simplex-1), the major late adenovirus promoter (MLP) and vaccinia promoters (e.g. 7.5K, HSR, TK, p28, p11 and K1 L promoters). One may use synthetic promoters such as those described in particular by Chakrabarti et al. (1997, Biotechniques 23: 1094-1097), Hammond et al. (1997, J. Virological Methods 66: 135-138). Suitable cellular promoters include any promoter driving expression of cellular genes with a special interest for liver specific promoters such as those of phosphoglycero kinase (PGK; Adra et al., 1987, Gene 60: 65-74), albumin (Pinkert et al., 1987, Genes Dev. 1: 268-277), phosphoenol pyruvate carboxy kinase (PEPCK) (Eisenberger et al., 1992, Mol. Cell. Biol. 12: 1396-1403), cholesterol 7-alpha hydroylase (CYP-7) (Lee et al., 1994, J. Biol. Chem. 269: 14681-14689), alpha-1 antitrypsin (Ciliberto et al., 1985, Cell 41: 531-540), transferrine (Mendelzon et al., 1990, Nucleic Acids Res. 18: 5717-5721); and facteur IX (U.S. Pat. No. 5,814,716) genes.
The vectors of the invention may also comprise one or more additional means in order to improve the transcription rate or level of the nucleotide sequence of the invention in a given host cell, its stability, nuclear RNA transport and/or translation rate or level of the mRNA. Such means are well known by the skilled person and include for example 5′, 3′ non-coding sequences, intervening sequences, splicing sequences, Shine-Dalgarno sequence, Kozak sequence and initiator methionine.
The vectors of the invention can also comprise sequences necessary for the screening of the peptides towards particular cell compartments. An example of screening can be screening towards the endoplasmic reticulum obtained using orientation sequences of the type of the leader sequence originating from the protein E3 of the adenovirus (Ciernik I. F., et al., The Journal of Immunology, 1999, 162: 3915-3925).
The expression vectors of the invention can comprise either a single nucleotide sequence coding for any one of the peptides of the invention, or at least two nucleotide sequences, it being understood that each nucleotide sequence codes for a peptide of different type.
According to one embodiment of the invention, the expression vectors include two nucleotide sequences coding for the A and B, A and C, A and D, B and C, B and D, or D and C peptides.
Preferably, the expression vectors include two nucleotide sequences coding for the A and B, A and C, B and D, or C and D peptides, the vectors comprising two sequences coding for the A and B, C and D, and B and D peptides being particularly preferred.
According to another embodiment, the expression vectors include three nucleotide sequences coding for the A, B and C, A, B and D, A, C and D, or B, C and D peptides.
According to yet another method, the expression vectors include four nucleotide sequences coding for the A to D peptides.
Preferably, the vectors include three nucleotide sequences coding for the A, B and C, A, C and D, and B, C and D peptides. More preferably, the vectors include four nucleotide sequences coding for the A, B, C, and D peptides. In this case, the order of the nucleotide sequences is relatively unimportant, as in the preceding combinations, such that the following combinations, given relative to the peptides, are comprised within the scope of the invention: A/B/C/D, A/B/D/C, A/C/B/D, A/C/D/B, A/D/B/C, A/D/C/B, B/A/C/D, B/A/D/C, B/C/A/D, B/C/D/A, B/D/A/C, B/D/C/A, C/A/B/D, C/A/DB, C/B/A/D, C/B/D/A, C/D/A/B, C/D/B/A, D/A/B/C, D/A/C/B, DB/A/C, D/B/C/A, D/C/A/B and D/C/B/A. The more preferred combination is B/A/C/D, and especially the B/A/C/D fusion peptide previously defined.
The expression vectors of the invention can also comprise at least one nucleotide sequence coding for any one of the B′ and C′ epitopes as defined previously, which constitutes another embodiment of the invention.
Thus, the vectors of the invention can comprise for example:
The vectors of the invention can also comprise from two to four nucleotide sequences chosen from the sequences coding for the A, B, C, D peptides and the B′ and C′ epitopes, it being understood that:
Thus, for example, the vectors of the invention can comprise the following combinations, given relative to said peptides and epitopes: A/B′, A/C′, A′/D, B/C′, B′/C, B′/D, C′/D, A/B′/C, A/B′/C′, A/B/C′, A/B′/D, A/C′/D, B′/C/D, B/C′/D, B′/C′/D, A/B′/C/D, A/B/C′/D and A/B′/C′/D.
Of course, as previously, the order of the nucleotide sequences in the expression vectors is relatively unimportant.
When the expression vectors of the invention include several nucleotide sequences, said sequences can be linked to each other directly, or via spacing or binding agents which are typically made up of small neutral molecules such as amino acids or amino acid mimetics which typically have a neutral charge under physiological conditions. Direct linkage of the peptide-encoding nucleotide sequences each other in a fusion peptide is preferred in the context of the invention.
In a preferred embodiment of the invention, the at least two nucleotide sequences are linked in the same reading frame. The expression “linked in the same reading frame” implies that in said reading frame, there is no stop codon between said two nucleotide sequences.
As spacing agents, there can be mentioned the Ala, Gly residues or other neutral spacing agents of non-polar amino acids or neutral polar amino acids.
These amino acid spacers have at least one or two residues and usually from 3 to 6 residues.
A subject of the invention is also the microorganisms and eukaryotic cells transformed by an expression vector of the invention. In the context of the invention, the term “transformation” or “transformed” has to be understood as meaning “introduction” or “introduced” in a host cell. Any routine method can be used in the art to “transform” a nucleotide sequence or a vector in a host cell, e.g. a microorganism or eukaryotic cell.
Such methods include, but are not limited to, microinjection (Capechi et al., 1980, Cell 22, 479-488), CaPO4-mediated transfection (Chen and Okayama, 1987, Mol. Cell. Biol. 7, 2745-2752), DEAE-dextran-mediated transfection, electroporation (Chu et al., 1987, Nucleic Acid Res. 15: 1311-1326), lipofection/liposome fusion (Feigner et al., 1987, Proc. Natl. Acad. Sci. USA 84: 7413-7417), particle bombardement (Yang et al., 1990, Proc. Natl. Acad. Sci. USA 87: 9568-9572), gene guns, transduction as well as viral infection. For example, in the context of the invention, a viral vector can be transformed in the host cell by transfection of its genome or by infection of a viral particle. The term “host cell” should be understood broadly without any limitation concerning microorganisms and eukaryotic cells including isolated cells or cells organized in particular structures such as tissues and organs. The host cells may be of a unique type of cells or a group of different types of cells and encompass cultured cell lines, primary cells and proliferative cells.
When a composition of the invention containing at least two A to D peptides of the invention is to be obtained, the microorganisms or eukaryotic cells are transformed by an expression vector containing at least two nucleotide sequences, or they are cotransformed by at least two expression vectors containing a single nucleotide sequence, each vector coding for a peptide of different type.
According to one embodiment of the invention, the microorganisms and eukaryotic cells are cotransformed with:
Similarly, when a composition of the invention is to be obtained containing at least two B′ and C′ epitopes, or at least one B′ or C′ epitope and at least one A to D peptide, the microorganisms or eukaryotic cells are transformed by a single vector coding for the desired combination of epitopes or epitopes/peptides or by several vectors each coding for each constituent of the desired combination.
As examples of microorganisms which are appropriate for the purposes of the invention, there can be mentioned yeasts, such as those of the following families: Saccharomyces, Schizosaccharomyces, Kluveromyces, Pichia, Hanseluna, Yarowia, Schwaniomyces, Zygosaccharomyces, Saccharomyces cerevisiae, Saccharomyces carlsbergensis and Kluveromyces lactis being preferred; and bacteria, such as E. coli and those of the following families: Lactobacillus, Lactococcus, Salmonella, Streptococcus, Bacillus and Streptomyces.
As examples of eukaryotic cells, there can be mentioned cells originating from animals such as mammals, reptiles, insects and equivalent. The preferred eukaryotic cells are cells originating from the Chinese hamster (CHO cells), monkey (COS and Vero cells), baby hamster kidney (BHK cells), pig kidney (PK 15 cells) and rabbit kidney (RK13 cells, human osteosarcoma cell lines (143 B cells), human HeLa cell lines and human hepatoma cell lines (Hep G2 cell type), as well as insect cell lines (for example of Spodoptera frugiperda).
The host cells can be supplied in cultures in suspension or in vials, in tissue cultures, organ cultures and equivalent. The host cells can also be from transgenic animals. Host cells of the present invention can be cultured in conventional fermentation bioreactors, flasks, and petri plates. Culturing can be carried out at a temperature, pH and oxygen content appropriate for a given host cell. No attempts to describe in detail the various methods known for the production of polypeptides in microorganisms and eukaryote cells will be made here.
The peptides and fusion peptides of the invention can be purified from the producing host cells by well-known purification methods including ammonium sulfate precipitation, acid extraction, gel electrophoresis, filtration and chromatographic methods (e.g. reverse phase, size exclusion, ion exchange, affinity, phosphocellulose, hydrophobic-interaction, hydroxylapatite, or high performance liquid chromatography). The conditions and technology used to purify a particular peptide or fusion peptide of the invention will depend on factors such as net charge, molecular weight, hydrophobicity, hydrophilicity and will be apparent to those having skill in the art. Moreover, the level of purification will depend on the intended use.
The invention also relates to antibodies directed against one of the abovementioned peptides of the invention or against one of the peptide compositions of the invention as defined previously, or also against one of the epitopes of the invention.
The antibodies according to the invention are either polyclonal or monoclonal antibodies.
The abovementioned polyclonal antibodies can be obtained by immunization of an animal with at least one viral antigen of interest, followed by the recovery of the sought antibodies in purified form, by taking a sample of the serum of said animal, and separation of said antibodies from the other constituents of the serum, in particular by affinity chromatography on a column on which an antigen specifically recognized by the antibodies, in particular a viral antigen of interest, is fixed.
The monoclonal antibodies can be obtained by the hybridoma technique, the general principle of which is recalled hereafter.
Firstly, an animal, generally a mouse, (or cells in culture within the framework of in vitro immunizations) is immunized with a viral antigen of interest, the B lymphocytes of which are then capable of producing antibodies against said antigen. These antibody-producing lymphocytes are then fused with “immortal” myelomatous cells (murine in the example) in order to produce hybridomas. From the heterogeneous mixture of the cells thus obtained, a selection is then made of cells capable of producing a particular antibody and multiplying indefinitely. Each hybridoma is multiplied in clone form, each leading to the production of a monoclonal antibody the recognition properties of which vis-à-vis the viral antigen of interest can be tested for example in ELISA, by immunotransfer in one or two dimensions, in immunofluorescence, or using a biocaptor. The monoclonal antibodies thus selected are subsequently purified in particular according to the affinity chromatography technique described above.
The compositions of the invention, containing at least two A to D peptides or at least one of the B′ and C′ epitopes or a fusion peptide as described previously, are particularly effective for the inhibition, prevention and treatment of the virus or infection of patients carrying the virus belonging more particularly to the genotypes 1a, 1b and 4, in such a manner that its use for the preparation of a medicament constitutes another subject of the invention.
The present invention also relates to a pharmaceutical composition, in particular a vaccine, containing as active ingredient at least two different peptides chosen from the A to D peptides as defined previously, or at least two nucleotide sequences as described previously, placed under the control of elements necessary for a constitutive and/or inducible expression of said peptides, or at least one of the antibodies as defined previously, or also at least one of the B′ and C′ epitopes as defined previously, or at least one of their nucleotide sequences, in combination with a pharmaceutically appropriate vehicle.
The present invention also relates to a pharmaceutical composition, in particular vaccine, containing as active ingredient at least a fusion peptide as defined previously or at least a nucleotide sequence or a vector or a host cell as defined previously encoding the fusion peptide of the invention, placed under the control of the elements necessary for a constitutive and/or inducible expression of said fusion peptide in a given host cell, in combination with a pharmaceutically appropriate vehicle.
By elements necessary for a constitutive expression of the peptides/fusion peptide, is meant a ubiquitous or specific promoter of the eukaryotic cells as previously described.
As elements necessary for an inducible expression of the peptides, there can be mentioned the elements of regulation of the operon of E. coli for resistance to tetracycline (Gossen M. and al, Proc Natl Acad Sci USA, 89: 5547-5551 (1992).
Of course, a person skilled in the art will easily determine the pharmaceutically appropriate vehicle and the quantity of active ingredient to be used as a function of the constituents of the pharmaceutical composition. Preferably, the composition of the invention contains the active ingredient or a combination of active ingredients at a dose sufficient for the alleviation of one or more symptoms normally associated with the disease or condition desired to be treated. When prophylactic use is concerned, this means a dose sufficient to prevent or to delay the establishment of a chronic HCV infection. For example, the active ingredient or a combination thereof is preferably contained in the composition of the invention at a dose sufficient for inducing a specific immune response in the treated host (e.g. resulting in the development of an anti-HCV response, whether humoral or cellular or both, with a special preference for a cytolytic T cell response).
The appropriate dosage can be adapted as a function of various parameters, in particular the mode of administration; the composition employed; the age, health, and weight of the patient to be treated; the nature and extent of symptoms; kind of concurrent treatment; the frequency of treatment; and/or the need for prevention or therapy. Further refinement of the calculations necessary to determine the appropriate dosage for treatment is routinely made by a practitioner, in the light of the relevant circumstances. For general guidance, suitable dosage for a virus-comprising composition (e.g. vaccinia or adenovirus particles) varies from about 105 to 1013 iu (infectious units), desirably from about 106 and 1012 iu. A composition based on vector plasmids may be administered in doses of between 10 μg and 20 mg, advantageously between 100 μg and 2 mg. A peptide composition may be administered in one or more doses of between 10 ng and 20 mg, with a special preference for a dosage from about 0.1 μg to about 2 mg of peptide(s) per kg body weight. The administration may take place in a single dose or a dose repeated one or several times after a certain time interval.
As used herein, a “pharmaceutically appropriate vehicle” is intended to include any and all carriers, solvents, diluents, excipients, adjuvants, dispersion media, coatings, antibacterial and antifungal agents, and absorption delaying agents compatible with pharmaceutical administration. The composition of the invention can be in various forms, e.g. solid, liquid or frozen. Solid (e.g. dry powdered or lyophilized) compositions can be obtained by a process involving vacuum drying and freeze-drying.
Suitably, the pharmaceutical composition of the invention comprises a diluent appropriate for human or animal use. It is preferably isotonic, hypotonic or weakly hypertonic and has a relatively low ionic strength. Representative examples include sterile water, physiological saline (e.g. sodium chloride), Ringer's solution, glucose, trehalose or saccharose solutions, Hank's solution, and other aqueous physiologically balanced salt solutions (see for example the most current edition of Remington: The Science and Practice of Pharmacy, A. Gennaro, Lippincott, Williams&Wilkins). The composition of the invention is suitably buffered in order to be appropriate for human use at a physiological or slightly basic pH (e.g. between about pH 7 to about pH 9). Suitable buffers include without limitation phosphate buffer (e.g. PBS), bicarbonate buffer and/or Tris buffer.
The pharmaceutically appropriate vehicles included in the composition of the invention must also permit to preserve its stability under the conditions of manufacture and long-term storage (i.e. at least one month) at freezing (e.g. −70° C., −20° C.), refrigerated (e.g. 4° C.) or ambient temperatures. In this respect, formulations which are particularly adapted to the composition of the invention include:
In addition, the composition of the invention may comprise one or more adjuvant(s) suitable for systemic or mucosal application in humans. Preferably, the adjuvant is capable of stimulating immunity to the composition of the invention, especially a T cell-mediated immunity e.g. through the toll-like receptors (TLR). Suitable adjuvants are well known in the art. Representative examples include without limitation alum, mineral oil emulsion such as Freunds complete and incomplete (IFA), lipopolysaccharide (Ribi et al., 1986, Immunology and Immunopharmacology of Bacterial Endotoxins, Plenum Publ. Corp., NY, p407-419), saponins (Sumino et al., 1998, J. Virol. 72, 4931-4939; WO 98/56415), imidazo-quinoline compounds (Suader, 2000, J. Am. Acad Dermatol. 43, S6-S11; Smorlesi, 2005, Gene Ther. 12, 1324-1332), and cationic peptides (Kritsch et al., 2005, J. Chromatogr Anal. Technol Biomed Life Sci 822, 263-270).
The composition of the present invention may be administered by a variety of modes of administration, including systemic, topical and localized administration. Injection can be performed by any means, for example by subcutaneous, intradermal, intramuscular, intravenous, intraperitoneal, intratumoral, intravascular, intraarterial injection or by direct injection into an artery (e.g. by hepatic artery infusion) or a vein feeding liver (e.g. injection into the portal vein). Injections can be made with conventional syringes and needles, or any other appropriate devices available in the art. Topical administration can also be performed using transdermal means (e.g. patch and the like). Administration via mucosal route can also be envisaged (e.g. intranasal, intravaginal). In the context of the invention, intramuscular and subcutaneous administrations constitute the preferred routes.
The pharmaceutical composition of the invention may be employed in methods for treating a variety of diseases and pathologic conditions, especially those associated with an HCV infection. As used herein, the term “treatment” or “treating” encompasses prophylaxis and/or therapy. It is especially useful for treating HCV persistent infection and liver cancer in HCV-infected patients. The term “cancer” encompasses any cancerous conditions including diffuse or localized tumors, metastasis, cancerous polyps as well as preneoplastic lesions (e.g. cirrhosis). Preferably, upon introduction into a host organism according to the modalities described herein, the composition of the invention provides a therapeutic benefit to the treated host. The term “host organism” is intended to encompass mammals including humans infected with HCV. The therapeutic benefit can be evidenced by a number of ways, for instance a decrease of HCV viremia detected in blood, plasma or sera of an infected mammal as compared to before treatment, and/or by the detection of an anti-HCV immune response (e.g. production of anti-HCV antibodies and/or T cell-mediated immunity) and/or by a modification of the proteomic profile analyzed before and after therapy (e.g. using the Gene Array Affimetrix technology on blood cells) and/or by the delay of the symptoms associated with an HCV infection (e.g. delay in the development of liver cirrhosis or cancer), and/or by a decrease of liver inflammation/steatosis/fibrosis conditions typically associated with HCV infection or by an improved response of the mammal to conventional therapies.
The invention also relates to a diagnostic composition for the detection and/or quantification of the hepatitis C virus comprising at least two different peptides chosen from the A to D peptides as defined previously, or at least one B′ or C′ epitope as defined previously, or at least one antibody as defined previously.
There also, a person skilled in the art will easily determine the quantity of peptides to be used as a function of the diagnostic technique used.
The invention also relates to a process for detection and/or quantification of the hepatitis C virus in a biological sample taken from an individual capable of being infected by said virus, such as plasma, serum or tissue, characterized in that it comprises stages consisting of:
The processes of detection and/or quantification of the virus are implemented using standard techniques well known to a person skilled in the art and there can be mentioned, by way of illustration, blots, so-called sandwich techniques, competition techniques and PCR detection techniques, in particular so-called “real-time” techniques.
The invention also relates to the use of the compositions of the invention for the in vitro diagnosis of the hepatitis C virus in a biological sample.
Finally, the invention relates to the use of the compositions of the invention for the preparation of a vaccine composition.
In a preferred embodiment, the present invention relates to the use of the peptide composition, fusion peptide, nucleotide sequence, vector, host cell or pharmaceutical composition of the invention for the preparation of a drug intended for inhibiting or treating or preventing HCV infections, HCV-associated diseases and pathologic conditions, in an animal, preferably human, according to the modalities described above.
The present invention also provides a method for the treatment or prevention of a human or animal organism, comprising administering to said organism a therapeutically effective amount of the peptide composition, fusion peptide, nucleotide sequence, vector, host cell or pharmaceutical composition of the invention. If desired, the method of the invention can be carried out in conjunction with one or more conventional therapeutic modalities (e.g. radiation, chemotherapy antiviral treatment and/or surgery). The use of multiple therapeutic approaches provides the patient with a broader based intervention.
The method or use of the invention may be carried out according to a prime boost therapeutic modality which comprises sequential administration of one or more primer composition(s) and one or more booster composition(s). Typically, the priming and the boosting compositions use different vehicles which comprise or encode at least an antigenic domain in common. In the context of the invention, a composition of the invention may be used to either prime or boost or both prime and boost an anti-HCV immune response. For illustrative purposes, one may prime with a fusion peptide having the amino acid sequence shown in SEQ ID NO: 234 and boost with a vector encoding an antigenic domain in common with the composition of the invention (e.g. an antigenic domain of NS3, NS4 and/or NS5B polypeptide). The source of such material is wide and includes without limitation peptides, proteins, viral vector from a variety of viruses, plasmid DNA, proteinaceous particles such as virus-like particles (Burns et al., 1994, Mol. Biol. Techno. 1: 137-145), cellular materials such as irradiated cells, virus particles (e.g. as described in WO2004/111082), etc. Alternatively, one may prime with the adenovirus particles of WO2004/111082 and subsequently boost with a MVA vector encoding the fusion peptide as defined in SEQ ID NO: 234. However other prime boost combinations are also possible in the context of the invention.
The present invention also provides a method of inducing or stimulating an immune response against HCV in a host organism comprising administering to said organism the peptide composition, fusion peptide, nucleotide sequence, vector, host cell, antibodies or pharmaceutical composition of the invention so as to induce or stimulate said immune response. The immune response can be a specific and/or a nonspecific, a humoral and/or a cell-mediated response. The immune response is preferably a T cell-mediated response directed to a T cell-recognized HCV epitope. The ability of the method of the invention to induce or stimulate an anti-HCV immune response upon administration in an animal or human organism can be evaluated either in vitro or in vivo using a variety of assays which are standard in the art (see for example Coligan et al., 1992 and 1994, Current Protocols in Immunology; ed J Wiley & Sons Inc, National Institute of Health). Measurement of cellular immunity can be performed by measurement of cytokine profiles secreted by activated effector cells including those derived from CD4+ and CD8+ T-cells (e.g. quantification of IL-10 or IFNg-producing cells by ELlspot), by determination of the activation status of immune effector cells (e.g. T cell proliferation assays by a classical [3H] thymidine uptake), by assaying for antigen-specific T lymphocytes in a sensitized subject (e.g. peptide-specific lysis in a cytotoxicity assay). The ability to stimulate a humoral response may be determined by antibody binding and/or competition in binding (see for example Harlow, 1989, Antibodies, Cold Spring Harbor Press). The method of the invention can also be further validated in animal models challenged with an appropriate infectious or tumor-inducing agent (e.g. surrogate murine challenge assays described in the art using for example a recombinant Listeria expressing NS3, a NS2-NS5 vaccinia virus) to determine neutralization of the infectious or tumor-inducing agent and eventually partial resistance to the associated symptoms, reflecting an induction or an enhancement of an anti-HCV immune response. Testing and validation of the compositions of the invention are also illustrated in the appended Example section.
The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced in a different way from what is specifically described herein.
All of the above cited disclosures of patents, publications and database entries are specifically incorporated herein by reference in their entirety to the same extent as if each such individual patent, publication or entry were specifically and individually indicated to be incorporated by reference.
The present invention will be better understood using the following examples given only by way of illustration and non-limitatively, as well as using the attached
1a: Test on Human Cells
The ability of blood cells from 3 patients infected by the hepatitis C virus of genotype 1 and having an HLA of type HLA-A2+ to produce gamma-interferon cytokines and interleukin-10, in response to two peptides predicted by software developed by bioMerieux (Centre d'Immunologie de Pierre Fabre) to bind to the HLA-A2 molecule was tested.
The assay of these cytokines reflects the ability of the peptides to induce immune responses to cell mediation, either of type 1 (gamma interferon), or of type 2 (interleukin-10)
In order to do this, the FLAT (FLATCVNGV) and LLG (LLGCIITSL) epitopes included in the B peptide of the invention, which have equivalent binding scores (694 for FLAT and 619 for LLG) were used.
Mononucleated blood cells from 3 infected patients (200,000 cells per well) were incubated in an ELISPOT plate (Human IL10 Elispot Set, San Diego, Calif., USA) on which biotinylated antibodies specific to gamma interferon (BD kit) or interleukin-10 (purified mouse anti-human γ-IFN monoclonal antibody, BD, No. 554548) had been previously fixed, in the presence of the FLAT and LLG peptides.
After 48 hours of incubation at 37° C., a period during which the cells specific to the peptides will locally produce cytokines which will bind to the specific antibodies, anti-gamma interferon or anti-interleukin-10 antibodies, alkaline phosphatase coupled to avidine and the alkaline phosphatase substrate (NBT/BCIP) were added.
The violet-blue spots, which represent each gamma-interferon or interleukin-10-producing cell were counted, using Zeiss's ELISPOT automated reader (KS Elispot) and only considered positive when the number of spots per well was greater than 20.
The results obtained are shown
In fact, the FLAT peptide induces little if any production of the two cytokines in the three patients, whereas the LLG peptide induces a significant production of gamma interferon in 2 of the 3 patients and of interleukin-10 in the three patients.
The results obtained also show that the peptides of the invention, as well as their combination was not evident with regard to the teachings of the prior art.
1b: Test on Murine Cells
Mice transgenic for the molecule HLA.A2.1 and devoid of murine class 1 molecules (Pascolo S., et al., 1997, J. Exp Med., 185: 2043-2051) were immunized with the FLL and ILA epitopes predicted as being class I epitopes restricted by the molecule HLA.A2.1. The FLL peptide has an average score (515) whereas the ILA peptide has a very high score (893).
In order to do this, the mice were immunized in the base of their tails with a peptide mixture containing one of the above epitopes (60 μM) and the T-helper peptide (Lone, Y. C. et al., (1998), J. Immunother. 21:283-294) (60 μM) emulsified in incomplete Freund's adjuvant (Sigma St Louis, Mo.). The mice received two injections with an interval of two weeks and the immune responses were analyzed two weeks after the last immunization as indicated in Example 1 (Elispot).
The results are shown in Table 1 below.
1Gamma-interferon-producing cells
These results show that the score ascribed to a peptide does not reflect its immunogenicity.
HLA-A2.1-transgenic mice were immunized either with the A peptide of sequence SEQ ID NO: 3, or with the B peptide of sequence SEQ ID NO: 47, or with the C peptide of sequence SEQ ID NO: 129, or with the D peptide of sequence SEQ ID NO: 176, or with the B′ epitope of sequence SEQ ID NO: 214 or with the ATL and ALY epitopes of the prior art contained respectively in the A and D peptides (ATLGFGAYM, amino acids 1260-1268 of the viral polyprotein and ALYDVVSTL, amino acids 2594-2602 of the viral polyprotein).
In order to do this, 2 sub-cutaneous injections were administered into the base of the tail of each mouse, with an interval of 15 days, of a mixture containing 18 nmoles of peptide of the invention and 18 nmoles of the HBV core helper peptide in incomplete Freund's adjuvant (IFA, Brinster et al., Hepatology 2001) or containing 60 nmoles of epitope of the invention and 60 nmoles of the helper peptide in IFA.
The control mice received only the helper peptide in IFA.
Fifteen days after the 2nd injection, the cell response was analyzed by isolating the spleen cells (splenocytes) of mice and a CTL test and an ELISPOT test were carried out as follows:
For the CTL test, these splenocytes were cultured in 24-well plates in the presence of 5 μM of the peptide or epitope of interest and 10 U of recombinant murine interleukin-2 (Brinster et al., Hepatology 2001) per ml in alpha minimum essential medium (αMEM) for 5 days. On the 5th day, the restimulation stage was carried out, consisting of adding to the splenocytes in culture splenocytes of naïve mice in the presence of the peptide or epitope of interest over 2 days. On the 7th day, the CTL test itself was carried out, consisting of bringing together the splenocytes of the immunized mice after the 7 days of culture (effective cells) and EL4 S3-Rob HDD cells charged with 10 μM of the peptide or epitope of interest marked with Cr51 (target cells). The specific cytotoxic activity of the effective cells was determined by measuring, after 4 hours of incubation with the target cells, the Cr51 released following the lysis of the target cells using a γ-Cobra II (Packard, Rungis, France) counting device. The spontaneous and maximum release from wells containing either the medium alone, or the lysis buffer (HCl 1N) were determined. The specific percentage of cytotoxicity was calculated by the formula:
(release in the test−spontaneous release)/(maximum release−spontaneous release)×100. The peptide or epitope-specific lysis was determined by the difference between the percentage of specific lysis obtained in the presence or absence of the peptide or epitope.
The ELISPOT test was carried out by culturing the splenocytes for 48 hours in Multiscreen (Millipore) 96-well plates previously coated with anti-□-interferon (γIFN) antibodies (10 μg/ml final). The splenocytes were cultured in the presence of 10 μM of peptide or epitope of interest and 10 U of recombinant murine interleukin-2 per ml in αMEM. For the positive control, the splenocytes were cultured in the presence of concanavalin A (5 μg/ml). For the negative control, the splenocytes were cultured either in the presence of a non-specific peptide belonging to the HCV capsid protein, of sequence DLMGYIPLV (also called irrelevant peptide), or in medium alone without peptide or epitope of interest. The wells were washed three times, respectively with PBS-Tween 0.05% then PBS, an operation followed by incubation for 2 hours with biotinylated anti-γ-IFN antibodies of mice. After washing, the wells were incubated for 1 hour with a streptavidin-horseradish peroxidase conjugate and the enzymatic activity was revealed by degradation of the AEC (aminoethylcarbazole) substrate. The spots obtained were counted using a Zeiss ELISpot reader (Zeiss microscope coupled with the KS-ELISpot software).
The results of the CTL tests are shown in
The results as shown in
(i) both said peptides and said epitopes have an immunogenic power, and
(ii) the peptides of the invention are capable of inducing immune responses specific to epitopes present in the natural infection.
It is to be noted that
The CTL test was also repeated injecting the composition ABCD or the B peptide taking the B′ epitope as target and injecting the composition ABCD or the C peptide taking the C peptide as target. The results are indicated in Table 3 below.
The results in the above table demonstrate that injection of the combination of the 4 A, B, C and D peptides induces a cytotoxic response more effective than injection of the peptides alone.
The results of the ELISPOT tests are shown in
The results shown in
Peripheral blood mononucleated cells from four patients chronically infected by the hepatitis C virus were purified by Ficoll gradient centrifugation. Two hundred thousand cells were pre-incubated at 37° C., 5% CO2, overnight in polypropylene tubes in the presence of the A to D peptides, having the amino acid sequences as defined in Example 2 above, and their compositions, in culture medium comprising RPMI1640 (Invitrogen Life technology, Cergy Pontoise, France) supplemented with 2 mM of L-Glutamine (Invitrogen Life Technology), 50 UI/ml of penicillin (Invitrogen Life Technology), 50 μg/ml of streptomycin (Invitrogen Life Technology) and 10% of f calf serum (Hyclone, Logan, Utah, USA) according to the following Table 4:
The peptides, alone or in combination, were present in the following concentrations: A at 10 μM, B at 5 μM, C at 1 μM and D at μM.
The cells were then transferred to an ELISPOT plate made of PVDF (polyvinylidene fluoride) previously coated with anti-γIFN antibodies according to the manufacturer's (Diaclone, Besancon, France) recommendations and incubated for another 24 hours at 37° C., 5% CO2. As previously, here cytokine-producing cells are sought, which will form blue spots which are revealed, after sequential incubation with a biotinylated anti-γIFN antibody and PAL coupled to streptavidin, by degradation of the BCIP/NBT (salt of 5-bromo-4-chloro-3-indolylphosphate p-toluidine/nitroblue tetrazolium chloride) substrate and which are counted using the Zeiss ELISPOT reader.
As positive control, the peptides/peptide compositions were replaced by tetanic toxin (TT) at 1 μg/ml.
This procedure was repeated starting with cells from HCV-seronegative patients.
The results are shown in
The results demonstrate that the peptide compositions of the invention have a strong immunogenic power.
Material and Methods
Peptides
The synthetic peptides used for Elispot and CTL assays were purchased from Eurogentec (Liège, Belgium). Seven peptides were generated with a purity of more than 85%, which sequences derived from the HCV-JA strain (Kato et al., 1990, Proc. Natl. Acad. Sci. USA 87: 9524-9528): ATLGFGAYM, GLLGCIITSL, CVNGVCWTV, LLFNILGGWV, SLMAFTASI, ALYDVVSTL, and RLIVFPDLGV, respectively referred as to ATL, GLL, CVN, LLF, SLM, ALY and RLI. They were dissolved in 100% DMSO at 10 μM and stored at −20° C. until use.
Cell Cultures
Human Huh 7 hepatoma cells were maintained at 37° C. in 5% CO2 atmosphere in complete DMEM medium containing Dulbecco's modified Eagles medium supplemented with 10% fetal calf serum, 2 mM L-Glutamine and 100 UI/ml penicillin/streptomycin (Sigma). HeLa cells (available at ATCC), a human cervix carcinoma cell line, were cultured according to supplier's instructions.
Mice
The HLA-A2.1 transgenic mice used for vaccination experiments are described in Pascolo et al. (1997, J. Exp. Med. 185: 2043-2051). These mice express a transgenic monochain histocompatibility class I molecule in which the C-terminus of the human β2-m is covalently linked to the N-terminus of a chimeric heavy chain composed of the HLA-A0201 α1 and α2 and H2-Db α3-transmembrane and intracytoplasmic domains. In addition, they are knocked out for the H2-Db and murine β2-m genes which were disrupted by homologous recombination. Mice were hosted in appropriate animal care facilities and handled following international guidelines required for experiments with animals.
Plasmids and Adenovirus Constructions
Three synthetic oligonucleotidic sequences were synthesised by Geneart (Regensburg, Germany) and cloned in pCR-Script Amp plasmids (Stratagene, La Jolla, US). The polyEp-WT minigene comprised a fusion of the wild-type nucleotide sequences (as found in the HCV JA genome) encoding B/A/C/D peptides. The polyEp-C minigene comprised a B/A/C/D encoding nucleotide sequence which codons had been optimized for translation in mammalian cells by computer software. The polyEp-E3 minigene encodes the B/A/C/D fusion with an N-terminal adenovirus E3 leader peptide (RYMILGLLALAAVCSA; SEQ ID NO: 233) for endoplasmic reticulum targeting.
The synthetic minigenes were amplified by PCR using appropriate primers incorporating a Kozack sequence and an AUG codon. The amplified sequences were inserted between the SalI and NotI sites of the gwiz plasmid (Gene Therapy System, San Diego, US), and placed under transcriptional control of the CMV promoter. The resulting gwiz constructions are named polyEp-WT, polyEp-C and polyEp-E3 respectively. A myc-tagged version was also generated. For this purpose, the above-described minigenes were inserted in the pcDNA3.1/myc-His/lacZ (Invitrogen, Carlsbad, US) in order to add a myc tag at the carboxy-terminus. The tagged minigenes were amplified by PCR as described above and inserted between SalI and NotI sites of the gwiz plasmid.
The myc-tagged minigenes were also cloned in E1-defective Ad5 vectors (kindly provided by the Gene Vector Production Network of Genethon, Paris, France), giving Ad-polyEp-WT, Ad-polyEp-C and Ad-polyEp-E3. As in the gwiz plasmids, the minigenes were placed under transcriptional control of the CMV promoter. Adenovirus stocks were produced in an appropriate packaging cell line such as 293 (Graham et al., 1977, J. Gen. Virol. 36: 59-72) or PERC.6 (Fallaux et al., 1998, Human Gene Ther. 9: 1909-1917) cells.
DNA Transfection and Adenovirus Infection
Human Huh7 cells were transfected with the different plasmid constructions described above in the presence of Lipofectamin/Plus Reagent (Invitrogen, Carlsbad, US). Briefly, 5×105 cells were plated in 6-well plates and 24 h later 1 μg of DNA was added to each well with Lipofectamin and Plus Reagent according to the manufacturer's instructions. HeLa or Huh7 cells were infected with the adenoviral vectors encoding the different myc-tagged minigenes at a MOI of 100. Briefly, 5×105 cells were plated in 6-well plates and 24 h later 5×107 iu of each adenovirus construction were added to each well.
Western Blot
Huh7 cells transfected by gwiz plasmids or infected with the different adenoviruses were incubated in ice-cold lysis buffer containing 1% NP40, 8M of urea and complete protease inhibitor (Roche Meyland). Lysed cells were centrifuged at 12,000 g for 10 min, and supernatants containing cytosolic fractions were assayed for protein concentrations (Comassie Blue, Pierce, Rockford, US) as described by the manufacturer. Equivalent protein amounts were loaded on a 12% acrylamide gel and run for 2 h. After electrophoretic transfer, polyvinylidene fluoride membranes (Hybond PVDF transfer membrane, Amersham, Uppsala, Sweden) were saturated and incubated with an anti-myc monoclonal antibody (dilution 1/5 000, Invitrogen, Carlsbad, US) and an anti-actin moclonal antibody (dilution 1/10 000, Sigma, Saint-Louis, US). Membranes were then incubated with an HRP-conjugated goat anti-mouse IgG antibody (1/10 000, Dako Cytomation, Glostrup, Denmark) and revealed by chemiluminescence (ECL Western-blotting Detection System, Amersham).
Immunofluorescence
Huh7 or HeLa cells were cultured and transfected or infected on coverslips in 6-well plates as previously described. 48 h post transfection or infection, cells were washed in 1×PBS, fixed with 1×PBS plus 4% paraformaldehyde followed by 1×PBS plus Glycine 0.1M and permeabilized with 1×PBS plus Triton 0.1%. Staining was carried out by sequential incubation with first anti-myc monoclonal antibody (mouse IgG, dilution 1/1000, Invitrogen, Carlsbad, US) or anti-calnexin monoclonal antibody (rabbit IgG, dilution 1/500, Stressgen, San Diego, US) for cellular localization experiments and then TRITC-conjugated goat anti-mouse IgG antibody (1/150, Sigma Aldrich) or FITC-conjugated swine anti-rabbit IgG antibody (dilution 1/40, Dako Cytomation). Antibody incubations and washes were done in PBS 1× plus BSA 0.1%. Cell nucleus were counter stained with Hoechst reagent (Sigma) at 1/200 diluted in PBS 80%-Glycerol 20%, observed using a fluorescence microscope (Zeiss, Le Pecq, France) and analysed with Adobe Photoshop 5.0.
Immunization Protocols
All plasmid DNA preparations were generated using endotoxin-free Macherey-Nagel purification columns (Macherey-Nagel, Duren, Germany) and adenovirus stocks were tested for the absence of endotoxins (Genethon, Paris, France). Six to eight week-old HLA-A2.1 transgenic mice were immunized with two intramuscular injections at 2-weeks intervals of 100 μg of gwiz plasmid, polyEp-WT, polyEp-C or polyEp-E3. Adenovirus immunization was carried out with one intramuscular injection of 109 IU of Ad-polyEp-WTmyc, Ad-polyEp-Cmyc or Ad-polyEp-E3myc. Control mice were injected with an empty gwiz plasmid or a non-recombinant adenoviral vector.
Elispot Assays
Splenocytes (2×105 cells per well) collected from immunized mice were cultured in triplicate for 40 h in Multiscreen plates (Millipore, France) coated with anti-mouse IFNγ monoclonal antibody (Pharmingen, France; 10 μg/ml) in complete αMEM culture medium (GIBCO BRL, France) in the presence of recombinant IL-2 (PeproTech Inc, England) at 10 U/mL alone as negative control, or with 10 μM of peptide (specific or irrelevant), or 5 μg/mL of Concavalin A as positive control. IFNγ-producing cells were quantified by cytokine-specific enzyme linked immunospot assay (ELISPOT) as previously described (Himoudi et al., 2002, J. Virol 76: 12735-12746). Each spot represents an individual IFNγ-producing cell. The number of spots in negative control was subtracted to the number of spots obtained in the experimental wells containing specific or irrelevant peptide. Results are shown as the mean value obtained for triplicate wells.
CTL Assays
CTL assays were performed as previously described (Brinster et al., 2001, Hepatology 34: 1206-1217). Briefly, spleen cells were stimulated for 7 days in the presence of 5 μM peptide and then re-stimulated on day 5 using irradiated cells loaded with 10 μM of the selected peptide. On day 7, the re-stimulated spleen cells were used as effector cells in a standard 51Cr-release assay against EL4S3-Rob HHD target cells, either loaded or not with 10 μM of the selected peptide. Effector and target cells were also used at different ratio. After 4 h incubation, 51Cr release was measured using a TopCount NXT counter (Packard). Spontaneous and total lysis were determined from wells containing target cells, loaded or not, either in medium alone or in lysis buffer (HCl 1N) respectively. Specific cytotoxicity was calculated using the formula: (release in assay−spontaneous release)/(total lysis−spontaneous release)×100. For each effector/target cell ratio, results are shown as the mean percentage of specific lysis obtained from duplicate points.
Listeria Monocytogenes Infectious Challenge
A recombinant and kanamycin-resistant Listeria Monocytogenes expressing the HCV NS3 protein (named TC-LNS3; Simon et al., 2003, Infect. Immunol. 71, 6372-6380) was inoculated intravenously to immunized mice 15 days after adenovirus immunization (an intramuscular administration of 109 IU/mice as described above). Mice were anaesthetized and received from 1 to 2 LD50 of TC-LNS3 (ILD50=9.107 pfu). Two days later, mice were sacrificed and pieces of liver and spleen were removed and weighted. The collected organ samples were homogenized in PBS/Tween 0.05% and residual bacterial titers were determined by serial dilution on BHI-agar plates (containing 30 μg/mL kanamycin). After 48 to 60 h of culture at room temperature, colonies obtained on plates were numerated and titers corresponding to numbers of bacteria per mg of organs were calculated.
Results
Both CD8+ and CD4+ lymphocytes mediated immune responses play a critical role in the outcome of HCV infection. Examples 2 and 3 demonstrate the capacity of four HCV peptides from non-structural protein NS3 (A and B peptides), NS4 (C peptide) and NS5B (D peptide) of inducing T cell responses alone or in various combinations in natural infection (Example 3) or in a transgenic mouse model (Example 2).
The four peptides were combined in a unique chimeric fusion peptide of 137 amino acids having the amino acid sequence disclosed in SEQ ID NO: 234 and comprising from N to C terminus B/A/C/D peptides (plus an initiator Met). Three minigene constructs were generated, respectively polyEp-WT, polyEp-C and polyEp-E3 which encode the same chimeric B/A/C/D fusion peptide but differ at the nucleotide level. The polyEp-WT construct comprises the “natural” nucleotide sequence as found in the HCV-JA genome encoding the 4 peptides fused in the B/A/C/D combination (SEQ ID NO: 235). In polyEp-C, the nucleotide sequence encoding each of the peptide has been optimized for translation in mammalian cells (SEQ ID NO: 236). The polyEp-E3 construct (SEQ ID NO: 237) encodes the B/A/C/D fusion preceded at its N-terminus by the leader sequence of the adenovirus E3 protein for endoplasmic reticulum (ER) targeting of the resulting 154 amino acid long polypeptide (Met+16 amino acid E3 leader sequence+137 amino acid B/A/C/D fusion). The minigene constructs were cloned in gwiz DNA plasmids and E1-defective adenovirus vectors under control of the CMV promoter in both cases.
Expression of the minigene products was evaluated by Western blot and immunofluorescence in Huh 7 cells transfected or infected with myc-tagged minigene vectors. Huh 7 cells transfected with an empty gwiz plasmid or infected with a non-recombinant adenoviral vector were used as negative controls. Myc-tagged fusion peptides were revealed using an anti-myc monoclonal antibody with or without MG132 proteasome inhibitor. Western blot analysis revealed a unique band having the expected molecular weight of approximately 16 KD for the fusion peptide encoded by polyEp-WT and polyEp-C and approximately 17 KD for the fusion peptide encoded by polyEp-E3. As expected, no proteins were highlighted in Huh 7 negative controls. Optimization of the minigene codons for mammalian translation does not result in a significant improvement of expression (approximately same level of expression in Huh 7 cells transfected with polyEp-WT plasmid as in Huh 7 cells transfected with polyEp-C). Interestingly, addition of the ER targeting E3 leader signal provides a partial protection from proteasome degradation as illustrated by the fusion peptide detected in the absence of MG132 in samples collected from Huh7 transfected polyEp-E3-encoding plasmid.
Immunofluorescence analysis confirmed expression of the minigene products in Huh 7 and HeLa transfected cells. Interestingly, fusion peptides encoded by polyEp-WT and polyEp-C plasmids showed a cytoplasmic localization whereas ER localisation is suggested for the fusion peptide encoded by polyEp-E3.
The immunogenic activity of the fusion peptides was evaluated in HLA-A2.1 transgenic mice immunized by two intramuscular injections at two weeks interval of plasmids encoding polyEp-WT, polyEp-C or polyEp-E3 (100 μg/injection/mouse). Specific anti-HCV T cell responses were analysed 15 days after the last immunization by Elispot and CTL assays against 7 HLA-A2 restricted epitopes contained in the fusion peptides, respectively ATL, GLL, CVN, LLF, SLM, ALY and RLI. As illustrated in
Specific cytolytic responses were also characterized by CTL assays in HLA-A2.1 transgenic mice twice immunized with minigene-encoding plasmids. Interestingly, as illustrated in
Immunogenicity of minigene-encoded fusion peptide was also evaluated in transgenic HLA-A2.1 immunized with an intramuscular injection of Ad-polyEp-WT, Ad-polyEp-C or Ad-polyEp-E3. As illustrated in
Cytolytic immune responses were measured by CTL assays against five HLA-A2 epitopes, four low inducer epitopes in DNA immunization assays (ATL, SLM, LLF and RLI) and a potent inducer epitope (CVN). After injection of the different minigene-encoding adenoviruses, no specific cytolytic response could be observed against SLM and RLI peptides. As illustrated in
The protective immunity conferred by the fusion peptides was evaluated in HLA-A2.1 transgenic mice immunized with the different minigene-encoding adenoviruses during a recombinant Listeria surrogate challenge assay. Mice received an intramuscular injection of Ad-polyEp-WT, Ad-polyEp-C or Ad-polyEp-E3 at Day 0 and were challenged by intravenous injection of TC-LNS3 15 days later. Control mice are injected under the same condition with a non-recombinant (i.e. empty) adenovirus. Mice were sacrificed two days after the challenge and residual bacterial titers were determined in spleens and livers. The results show that Ad-polyEp-WT and Ad-polyEp-E3 immunisations allowed a significant decrease of TC-LNS3 residual titers in spleen as compared to control mice. Based on the average titers observed for each group, this decrease is about 1 log for Ad-polyEp-WT and about 2 logs for Ad-polyEp-E3 as compared to empty adenovirus (p=0.0253 and p=0.0143 respectively, according to Mann Whitney statistical analysis). In livers, a significant decrease of TC-LNS3 residual titers was observed only for Ad-polyEp-E3 immunised mice (about 1.5 log of decrease considering the mean of each group) compared to control mice immunised with an empty adenoviral vector (p=0.0143 according to Mann Whitney statistical analysis).
In conclusion, immunization with DNA plasmids encoding the B/A/C/D fusion peptide was able to induce both IFNγ producing cells and cytolytic responses respectively directed against 2 to 4 HLA-A2 restricted epitopes, depending on the constructions and the assays employed. Equivalent induced T cell responses are observed for the three minigenes under the experimental conditions tested and codon optimization did not lead to any improvement. Interestingly, adenovirus vectorization induced the strongest T cell responses. More specifically, immunization with adenovirus vectors permits to broader spectrum of HLA-A2 restricted epitopes recognized by IFNγ-producing cells (2 epitopes out of 7 recognized after DNA immunization against 3 after Adenovirus immunization) and to maximize both the cytolytic and the IFNγ producing cell-mediated immune responses (higher level of specific lysis and higher number of spots when the mice are injected with the minigene-encoding adenoviruses than with DNA plasmids). A protective immunity was conferred by Ad-polyEp-WT and Ad-polyEp-E3 against a recombinant Listeria expressing the NS3 protein. Based on these results, vectorized minigenes encoding the B/A/C/D fusion peptide are potential HCV vaccine candidates.
| Number | Date | Country | Kind |
|---|---|---|---|
| 02/06111 | May 2002 | FR | national |
This application is a continuation of, and claims priority from U.S. Ser. No. 11/503,245, filed Aug. 11, 2006, which is a continuation-in-part of U.S. Ser. No. 10/514,762, filed Nov. 16, 2004 (now U.S. Pat. No. 7,393,831), which claims priority under 35 U.S.C. 371 from PCT/FR03/001478, filed May 15, 2003, which claims priority from French application no. 02/06111, filed May 17, 2002. The contents of each of the prior applications are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11503245 | Aug 2006 | US |
| Child | 12653751 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10514762 | Nov 2004 | US |
| Child | 11503245 | US |
