Recombinant viral vectors and methods for inducing a heterosubtypic immune response to influenza A viruses
The present invention relates to recombinant viral vectors and methods of using the recombinant viral vectors to induce an immune response to influenza A viruses. The invention provides recombinant viral vectors based, for example, on the non-replicating modified vaccinia virus Ankara. When administered according to methods of the invention, the recombinant viral vectors are designed to be cross-protective and induce heterosubtypic immunity to influenza A viruses.
1. A recombinant modified vaccinia virus Ankara (rMVA) comprising a gene cassette encoding a fusion protein comprising at least one influenza A M2 extracellular domain (M2e) polypeptide inserted in an influenza A headless hemagglutinin (h1HA) polypeptide set out in SEQ ID NO: 15.
2. The rMVA of claim 1 wherein the fusion protein comprises one selected from the group consisting of i) the h1HA/M2e fusion protein amino acid sequence set out in SEQ ID NO: 2, ii) the VN/1203 HA amino acid sequence set out in SEQ ID NO: 3, and iii) HA1 amino acids 17-58 of SEQ ID NO: 3, a peptide linker, at least one M2e polypeptide, a peptide linker, HA1 amino acids 290-343 of SEQ ID NO: 3 and HA2 amino acids 344-568 of SEQ ID NO: 3.
3. The rMVA of claim 2 , wherein the peptide linkers linking the HA amino acids and M2e amino acids comprise the amino acids GGG set out in SEQ ID NO: 4.
4. The rMVA of claim 1 , wherein the fusion protein comprises i) the H5N1 M2e amino acid sequence set out in SEQ ID NO: 5, ii) the H1N1 M2e amino acid sequence set out in SEQ ID NO: 6, iii) the H9N2 M2e amino acid sequence set out in SEQ ID NO: 7, and iv) the H7N2 M2e amino acid sequence set out in SEQ ID NO: 8.
5. The rMVA of claim 1 , wherein the fusion protein comprises more than one M2e polypeptide and the M2e polypeptides are linked by a peptide linker.
6. The rMVA of claim 5 , wherein the peptide linker linking the M2e polypeptides comprises the amino acids GSAGSA set out in SEQ ID NO: 9.
7. The rMVA of claim 1 , wherein expression of the h1HA/M2e fusion protein from the gene cassette is under the control of an mH5 promoter or a selP promoter.
8. A recombinant vaccinia virus comprising the gene cassette set out in SEQ ID NO: 1.
9. The rMVA of claim 1 , further comprising a gene cassette encoding an influenza A matrix protein 1 (M1) and a gene cassette encoding an influenza A nucleoprotein (NP).
10. A recombinant modified vaccinia virus Ankara (rMVA) comprising a first gene cassette encoding a fusion protein comprising at least one influenza A M2 extracellular domain (M2e) polypeptide inserted in an influenza A headless hemagglutinin (h1HA) polypeptide and a second gene cassette encoding influenza A nucleoprotein (NP) set out in SEQ ID NO: 14.
11. The rMVA of claim 10 , wherein the fusion protein comprises one selected from the group consisting of i) the h1HA/M2e fusion protein amino acid sequence set out in SEQ ID NO: 2, ii) the VN/1203 HA amino acid sequence set out in SEQ ID NO: 3, and iii) HA1 amino acids 17-58 of SEQ ID NO: 3, a peptide linker, at least one M2e polypeptide, a peptide linker, HA1 amino acids 290-343 of SEQ ID NO: 3 and HA2 amino acids 344-568 of SEQ ID NO: 3.
12. The rMVA of claim 11 , wherein the peptide linkers linking the HA amino acids and M2e amino acids comprise the amino acids GGG set out in SEQ ID NO: 4.
13. The rMVA of claim 10 , wherein the fusion protein comprises i) the H5N1 M2e amino acid sequence set out in SEQ ID NO: 5, ii) the H1N1 M2e amino acid sequence set out in SEQ ID NO: 6, iii) the H9N2 M2e amino acid sequence set out in SEQ ID NO: 7, and iv) the H7N2 M2e amino acid sequence set out in SEQ ID NO: 8.
14. The rMVA of claim 10 , wherein expression of the h1HA/M2e fusion protein from the first gene cassette is under the control of an mH5 promoter or a selP promoter.
15. The rMVA of claim 10 , wherein expression of NP from the second gene cassette is under the control of an mH5 promoter or selP promoter.
16. A pharmaceutical composition comprising the rMVA of claim 1 .
17. A method for inducing a heterosubtypic immune response to influenza A viruses in an individual, the method comprising the step of administering a pharmaceutical composition comprising the rMVA of claim 10 to the individual.