Recombinant listeria vaccine strains and methods of producing the same

Abstract

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 .- 32 . (canceled) 
     
     
         33 . A method of inducing an immune response against a head and neck cancer in a human subject, the method comprising 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 listeriolysin 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 head and neck cancer. 
     
     
         34 . The method of  claim 33 , wherein said  Listeria  comprises a deletion, inactivation or mutation in the genomic prfA gene. 
     
     
         35 . The method of  claim 33 , 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. 
     
     
         36 . The method of  claim 33 , wherein said mutant PrfA protein is encoded by SEQ ID NO: 33. 
     
     
         37 . The method of  claim 33 , wherein said heterologous antigen is Human Papilloma Virus-E7 (HPV-E7) or HPV-E6. 
     
     
         38 . The method of  claim 37 , wherein said heterologous antigen is Human Papilloma Virus-E7 (HPV-E7). 
     
     
         39 . The method of  claim 38 , wherein said HPV-E7 is from HPV16. 
     
     
         40 . The method of  claim 37 , wherein said heterologous antigen is Human Papilloma Virus-E6 (HPV-E6). 
     
     
         41 . The method of  claim 33 , wherein the N-terminal fragment of a LLO protein is a fragment of SEQ ID NO: 3. 
     
     
         42 . The method of  claim 33 , wherein said N-terminal fragment of a LLO protein is selected from a sequence comprising SEQ ID NO: 2 or SEQ ID NO: 4. 
     
     
         43 . The method of  claim 33 , wherein the recombinant  Listeria  strain is a recombinant  Listeria monocytogenes  strain, the N-terminal fragment of a LLO protein is a fragment of SEQ ID NO: 3, and the heterologous antigen is HPV-E7 from HPV16. 
     
     
         44 . The method of  claim 33 , wherein said administering is intravenous or oral administering. 
     
     
         45 . The method of  claim 33 , wherein said recombinant  Listeria  strain is administered to said human subject at a dose of 1×10 7 -3.31×10 10  organisms. 
     
     
         46 . The method of  claim 45 , wherein said recombinant  Listeria  strain is administered to said human subject at a dose of 1×10 8 . 
     
     
         47 . The method of  claim 45 , wherein said recombinant  Listeria  strain is stored in a frozen or lyophilized condition prior to administering. 
     
     
         48 . The method of  claim 33 , further comprising administering to said subject an additional therapeutic agent. 
     
     
         49 . The method of  claim 33 , further comprising the step of boosting said human subject with said recombinant  Listeria  strain. 
     
     
         50 . The method of  claim 33 , wherein said recombinant  Listeria  strain is a recombinant  Listeria monocytogenes  strain. 
     
     
         51 . The method of  claim 33 , wherein said plasmid comprises a gene encoding a metabolic enzyme. 
     
     
         52 . The method of  claim 33 , wherein said immune response is a cytotoxic T cell anti-tumor immune response. 
     
     
         53 . The method of  claim 33 , wherein said method allows protecting a subject against a head and neck cancer. 
     
     
         54 . The method of  claim 33 , wherein said method allows treating a subject against a head and neck cancer.