Recombinant
The present invention provides methods of treating, protecting against and inducing an immune response against a tumor or cancer, comprising the step of administering to a subject a recombinant Listeria strain. In one embodiment the present invention relates to a recombinant Listeria strain, said recombinant Listeria strain comprising a recombinant nucleic add, said nucleic add comprising a first open reading frame encoding a recombinant polypeptide comprising a first N-terminal fragment of an LLO protein fused to a heterologous antigen or fragment thereof, and wherein said recombinant nucleic add further comprises a second open reading frame encoding a mutant PrfA protein.
1. A recombinant Listeria strain, said recombinant Listeria strain comprising an episomal plasmid comprising a recombinant nucleic acid, said nucleic acid comprising a first open reading frame encoding a recombinant polypeptide comprising an N-terminal fragment of a listerioly sin O (LLO) protein fused to a heterologous antigen, and wherein said recombinant nucleic acid further comprises a second open reading frame encoding a mutant PrfA protein comprising an amino acid sequence of SEQ ID NO: 34.
2. The recombinant Listeria of claim 1 , wherein said Listeria comprises a deletion, inactivation or mutation in the prfA gene.
3. The recombinant Listeria of claim 1 , wherein said mutant PrfA protein encoded by said second open reading frame complements said prfA genomic mutation, deletion or inactivation in said Listeria strain or restores partial PrfA function in said Listeria strain.
4. The recombinant Listeria of claim 1 , wherein said heterologous antigen is Human Papilloma Virus-E7 (HPV-E7) or HPV-E6.
5. The recombinant Listeria strain of claim 1 , wherein said N-terminal fragment of an LLO protein is selected from a sequence comprising SEQ ID NO: 2 or SEQ ID NO: 4.
6. The recombinant Listeria strain of claim 1 , wherein said recombinant Listeria strain is a recombinant Listeria monocytogenes strain.
7. The recombinant Listeria of claim 1 , wherein said plasmid comprises a gene encoding a metabolic enzyme.
8. A pharmaceutical composition comprising the recombinant Listeria of claim 1 and a pharmaceutically acceptable excipient.
9. A method of inducing an immune response against a tumor or a cancer in a human subject, the method comprising the step of administering to said subject a recombinant Listeria strain comprising an episomal plasmid comprising a recombinant nucleic acid, said nucleic acid comprising a first open reading frame encoding a recombinant polypeptide comprising an N-terminal fragment of a listerioly sin O (LLO) protein fused to a heterologous antigen, wherein said recombinant nucleic acid further comprises a second open reading frame encoding a mutant PrfA protein comprising an amino acid sequence of SEQ ID NO:34, thereby inducing an immune response against a tumor or a cancer.
10. The method of claim 9 , wherein said Listeria comprises a deletion, inactivation or mutation in the prfA gene.
11. The method of claim 9 , wherein said mutant PrfA protein encoded by said second open reading frame complements a prfA genomic mutation, deletion or inactivation in said Listeria strain or restores partial PrfA function in said Listeria strain.
12. The method of claim 9 , wherein said administering is intravenous or oral administering.
13. The method of claim 9 , wherein said heterologous antigen is Human Papilloma Virus-E7 (HPV-E7) or HPV-E6.
14. The method of claim 9 , wherein said N-terminal fragment of an LLO protein is selected from a sequence comprising SEQ ID NO: 2 or SEQ ID NO: 4.
15. The method of claim 9 , wherein said recombinant Listeria strain is administered to said human subject at a dose of 1×10 9 -3.31×10 10 organisms.
16. The method of claim 15 , wherein said recombinant Listeria strain is stored in a frozen or lyophilized condition prior to administering.
17. The method of claim 9 , wherein said recombinant Listeria strain is a recombinant Listeria monocytogenes strain.
18. The method of claim 9 , wherein said plasmid comprises a gene encoding a metabolic enzyme.
19. The method of claim 9 , further comprising the step of boosting said human subject with said recombinant Listeria strain.
20. The method of claim 9 , wherein said immune response is a cytotoxic T cell anti-tumor immune response.
21. The method of claim 9 , wherein said method allows protecting a subject against a tumor or cancer.
22. The method of claim 9 , wherein said method allows treating a subject against a tumor or cancer.
23. The method of claim 22 , wherein said cancer is cervical cancer, head and neck cancer (HNC) or anal cancer.
24. The recombinant Listeria of claim 2 , wherein said heterologous antigen is Human Papilloma Virus-E7 (HPV-E7) or Human Papilloma Virus-E6 (HPV-E6).
25. The recombinant Listeria of claim 4 , wherein said heterologous antigen is Human Papilloma Virus-E7 (HPV-E7).
26. The recombinant Listeria of claim 4 , wherein said heterologous antigen is Human Papilloma Virus-E6 (HPV-E6).
27. The method of claim 13 , wherein said heterologous antigen is Human Papilloma Virus-E7 (HPV-E7).
28. The method of claim 13 , wherein said heterologous antigen is Human Papilloma Virus-E6 (HPV-E6).
29. The recombinant Listeria of claim 1 , wherein said mutant PrfA protein is encoded by SEQ ID NO: 33.
30. The recombinant Listeria of claim 25 , wherein said HPV-E7 is from HPV16.
31. The method of claim 9 , wherein said mutant PrfA protein is encoded by SEQ ID NO: 33.
32. The method of claim 27 , wherein said HPV-E7 is from HPV16.