Immunogen platform
Aspects of the present invention relate to chimeric polypeptides including HCV NS3/4A sequences and T-cell epitopes. Embodiments include nucleic acids encoding the chimeric NS3/4A polypeptides, the encoded polypeptides, compositions containing said nucleic acids, compositions containing said chimeric polypeptides, as well as methods of making and using the aforementioned compositions including, but not limited to medicaments and vaccines.
1. An immunogenic composition comprising a nucleic acid molecule that comprises a nucleotide sequence encoding a heterologous chimeric hepatitis viral antigen comprising hepatitis C virus (HCV) NS3/4A antigen fused to a hepatitis B virus (HBV) core antigen, wherein the nucleotide sequence is modified to encode an amino acid sequence that comprises one or more protease cleavage site insertions at one or more non-naturally occurring positions and said immunogenic composition induces an effective cytotoxic T cell (CTL) immune response specific for one or more epitopes of said heterologous viral antigen.
2. The immunogenic composition of claim 1 , wherein said nucleotide sequence is modified to encode a mutant HCV NS3/4A antigen lacking a proteolytic cleavage site.
3. The immunogenic composition of claim 1 , wherein said nucleotide sequence is modified to encode a HCV NS3/4A antigen comprising a mutant non-functional NS3 protease.
4. The immunogenic composition of claim 1 , wherein said nucleotide sequence is modified to encode a HCV NS3/4A antigen comprising a mutant NS3 protease with enhanced protease activity.
5. The immunogenic composition of claim 1 , wherein said one or more non-naturally occurring positions are located between NS3/4A and said HBV core antigen.
6. The immunogenic composition of claim 1 , wherein said one or more non-naturally occurring positions are located within said HBV core antigen.
7. An immunogenic composition comprising a nucleic acid molecule that comprises a nucleotide sequence encoding a heterologous chimeric hepatitis viral antigen comprising hepatitis C virus (HCV) NS3/4A antigen fused to a plurality of antigenic fragments of hepatitis B virus (HBV) core antigen assembled in a non-naturally occurring order, wherein the nucleotide sequence is modified to encode an amino acid sequence that comprises one or more protease cleavage site insertions at one or more non-naturally occurring positions and said immunogenic composition induces an effective cytotoxic T cell (CTL) immune response specific for one or more epitopes of said heterologous viral antigen.
8. The immunogenic composition of claim 7 , wherein said nucleotide sequence is modified to encode a mutant HCV NS3/4A antigen lacking a proteolytic cleavage site.
9. The immunogenic composition of claim 7 , wherein said nucleotide sequence is modified to encode a HCV NS3/4A antigen comprising a mutant non-functional NS3 protease.
10. The immunogenic composition of claim 7 , wherein said nucleotide sequence is modified to encode a HCV NS3/4A antigen comprising a mutant NS3 protease with enhanced protease activity.
11. The immunogenic composition of claim 7 , wherein said one or more non-naturally occurring positions are located between NS3/4A and said plurality of antigenic fragments of HBV core antigen.
12. The immunogenic composition of claim 7 , wherein said one or more non-naturally occurring positions are located within said plurality of antigenic fragments of HBV core antigen.
13. An immunogenic composition comprising:
a DNA plasmid suitable for mammalian expression, wherein said plasmid comprises a promoter, which is functional in mammalian cells, operably linked to a nucleic acid sequence that encodes a heterologous chimeric hepatitis viral antigen comprising an (HCV) NS3/4A antigen fused to a hepatitis B virus (HBV) core antigen, wherein said nucleotide sequence is modified to encode an amino acid sequence that comprises one or more protease cleavage site insertions at one or more non-naturally occurring positions and wherein said DNA plasmid induces an effective cytotoxic T cell (CTL) immune response specific for one or more epitopes of said heterologous viral antigen.
14. The immunogenic composition of claim 13 , wherein said nucleotide sequence is modified to encode a mutant HCV NS3/4A antigen lacking a proteolytic cleavage site.
15. The immunogenic composition of claim 13 , wherein said nucleotide sequence is modified to encode a HCV NS3/4A antigen comprising a mutant non-functional NS3 protease.
16. The immunogenic composition of claim 13 , wherein said nucleotide sequence is modified to encode a HCV NS3/4A antigen comprising a mutant NS3 protease with enhanced protease activity.
17. The immunogenic composition of claim 13 , wherein said one or more non-naturally occurring positions are located between NS3/4A and said HBV core antigen.
18. The immunogenic composition of claim 13 , wherein said one or more non-naturally occurring positions are located within said HBV core antigen.