COMPOSITIONS AND METHODS FOR PREVENTION OF ESCAPE MUTATION IN THE TREATMENT OF HER2/NEU OVER-EXPRESSING TUMORS
This invention provides compositions and methods for treating and vaccinating against a Her2/neu antigen-expressing tumor and inducing an immune response against dominant in a non-human animal.
1 . A method of treating a Her-2/neu-expressing tumor growth or cancer in a non-human animal, the method comprising the step of administering a recombinant attenuated Listeria comprising nucleic acid encoding a fusion polypeptide, wherein said fusion polypeptide comprises a Her2/neu chimeric antigen fused to an additional adjuvant polypeptide, wherein said nucleic acid molecule comprises a first open reading frame encoding said fusion polypeptide, wherein said nucleic acid molecule further comprises a second open reading frame encoding a metabolic enzyme, and wherein said metabolic enzyme complements an endogenous gene that is lacking in the chromosome of said recombinant Listeria vaccine strain.
2 . The method of claim 1 , wherein said non-human animal is a dog.
3 . The method of claim 1 , wherein administering said fusion polypeptide to a subject having a Her2/neu-expressing tumor prevents escape mutations within said tumor.
4 . The method of claim 1 , wherein said Her2/neu chimeric antigen comprises at least 5, 9, 13, 14, or 17 of the mapped human MHC-class I epitopes.
5 . The method of claim 1 , wherein said nucleic acid molecule is integrated into the Listeria genome.
6 . The method of claim 1 , wherein said nucleic acid molecule is in a plasmid in said recombinant Listeria vaccine strain and wherein said plasmid is stably maintained in said recombinant Listeria vaccine strain in the absence of antibiotic selection.
7 . The method of claim 1 , wherein said recombinant Listeria lacks the ActA virulence gene.
8 . The method of claim 1 , wherein said additional polypeptide is selected from the group consisting of: a) non-hemolytic LLO protein or N-terminal fragment, b) a PEST sequence, or c) an ActA fragment.
9 . The method of claim 1 , wherein said metabolic enzyme encoded by said second open reading frame is an alanine racemase enzyme or a D-amino acid transferase enzyme.
10 . The method of claim 1 , further comprising an independent adjuvant.
11 . The method of claim 11 , wherein said adjuvant comprises a granulocyte/macrophage colony-stimulating factor (GM-CSF) protein, a nucleotide molecule encoding a GM-CSF protein, saponin QS21, monophosphoryl lipid A, or an unmethylated CpG-containing oligonucleotide.
12 . The method of claim 1 , wherein said tumor is a Her2/neu positive tumor and wherein said cancer is a Her2/neu-expressing cancer.
13 . The method of claim 1 , wherein said cancer is osteosarcoma, ovarian cancer, gastric cancer or a central nervous system (CNS) cancer.
14 . The method of claim 14 , wherein said osteosarcoma cancer is canine osteosarcoma.
15 . A method of eliciting an enhanced immune response against a Her-2/neu-expressing tumor growth or cancer in a non-human animal, the method comprising the step of administering a recombinant attenuated Listeria comprising a nucleic acid encoding a fusion polypeptide, wherein said fusion polypeptide comprises a Her2/neu chimeric antigen fused to an additional adjuvant polypeptide, wherein said nucleic acid molecule comprises a first open reading frame encoding said fusion polypeptide, wherein said nucleic acid molecule further comprises a second open reading frame encoding a metabolic enzyme, and wherein said metabolic enzyme complements an endogenous gene that is lacking in the chromosome of said recombinant Listeria vaccine strain.
16 . The method of claim 15 , wherein said non-human animal is a dog.
17 . The method of claim 15 , wherein administering said fusion polypeptide to a subject having a Her2/neu-expressing tumor prevents escape mutations within said tumor.
18 . The method of claim 15 , wherein said Her2/neu chimeric antigen comprises at least 5, 9, 13, 14, or 17 of the mapped human MHC-class I epitopes.
19 . The method of claim 15 , wherein said nucleic acid molecule is integrated into the Listeria genome.
20 . The method of claim 15 , wherein said nucleic acid molecule is in a plasmid in said recombinant Listeria vaccine strain.
21 . The method of claim 15 , wherein said plasmid is stably maintained in said recombinant Listeria vaccine strain in the absence of antibiotic selection.
22 . The method of claim 15 , wherein said recombinant Listeria lacks the ActA virulence gene.
23 . The method of claim 15 , wherein said additional polypeptide is selected from the group consisting of: a) non-hemolytic LLO protein or N-terminal fragment, b) a PEST sequence, or c) an ActA fragment.
24 . The method of claim 15 , wherein said metabolic enzyme encoded by said second open reading frame is an alanine racemase enzyme or a D-amino acid transferase enzyme.
25 . The method of claim 15 , further comprising an independent adjuvant.
26 . The method of claim 25 , wherein said adjuvant comprises a granulocyte/macrophage colony-stimulating factor (GM-CSF) protein, a nucleotide molecule encoding a GM-CSF protein, saponin QS21, monophosphoryl lipid A, or an unmethylated CpG-containing oligonucleotide.
27 . The method of claim 15 , wherein said tumor is a Her2/neu positive tumor and wherein said cancer is a Her2/neu-expressing cancer.
28 . The method of claim 15 , wherein said cancer is osteosarcoma, ovarian cancer, gastric cancer or a central nervous system (CNS) cancer.
29 . The method of claim 15 , wherein said osteosarcoma cancer is a canine osteosarcoma.
30 . The method of claim 16 , wherein said immune response against said Her2/neu-expressing tumor or cancer comprises an immune response to a subdominant epitope of said Her2/neu protein.