Influenza virus vaccines and uses thereof

1. A chimeric influenza virus hemagglutinin (HA) polypeptide comprising a stem domain of an HA from influenza virus A/California/4/2009 (H1N1) or A/California/4/2009 (H1N1)-like influenza virus HA and a globular head domain of an HA from an HA from influenza virus A/Vietnam/1203/2004 (H5) or an A/Vietnam/1203/2004 (H5)-like influenza virus HA.

2. The chimeric influenza virus HA polypeptide of claim 1 , wherein the stem domain of the HA maintains cysteine residues A p and A q , wherein A p is a Cys that corresponds to amino acid position 52 of an HA1 domain using H3 numbering, and wherein A q is a Cys that corresponds to amino acid position 277 of an HA1 domain using H3 numbering.

3. The chimeric influenza virus HA polypeptide of claim 1 , wherein:

(a) the HA stem domain comprises (i) an HA1 N-terminal stem segment, wherein the HA1 N-terminal stem segment consists of amino acid residues HA1 N-term through A p ; (ii) an HA1 C-terminal stem segment, wherein the HA1 C-terminal stem segment consists of amino acid residues A q through HA1 c-term ; and (iii) an HA2 stem domain; and

(b) the HA globular head domain comprises the amino acid residues between A p and A q of an HA1 domain;

wherein HA1 N-term is the N-terminal amino acid of a mature HA0 protein lacking a signal peptide; wherein HA1 c-term is the C-terminal amino acid of an HA1 domain; and wherein A p is the Cys that corresponds to amino acid position 52 of an HA1 domain using H3 numbering; and wherein A q is the Cys that corresponds to amino acid position 277 of an HA1 domain using H3 numbering.

4. The chimeric influenza virus HA polypeptide of claim 1 , wherein:

(a) the HA stem domain comprises (i) an HA1 N-terminal stem segment, wherein the HA1 N-terminal stem segment consists of amino acid residues HA1 N-term through A p−10 , A p−9 , A p−8 , A p−7 , A p−6 , A p−5 , A p−4 , A p−3 , A p−2 , A p−1 , A p , A p+1 , A p+2 , A p+3 , A p+4 , A p+5 , A p+6 , A p+7 , A p+8 , A p+9 , or A p+10 ; (ii) an HA1 C-terminal stem segment, wherein the HA1 C-terminal stem segment consists of amino acid residues A q−10 , A q−9 , A q−8 , A q−7 , A q−6 , A q−5 , A q−4 , A q−3 , A q−2 , A q−1 , A q , A q+1 , A q+2 , A q+3 , A q+4 , A q+5 , A q+6 , A q+7 , A q+8 , A q+9 , or A q+10 through HA1 c-term ; and (iii) an HA2 stem domain; and

(b) the HA globular head domain comprises the amino acid residues between (i) through A p−10 , A p−9 , A p−8 , A p−7 , A p−6 , A p−5 , A p−4 , A p−3 , A p−2 , A p−1 , A p , A p+1 , A p+2 , A p+3 , A p+4 , A p+5 , A p+6 , A p+7 , A p+8 , A p+9 , or A p+10 , and (ii) A q−10 , A q−9 , A q−8 , A q−7 , A q−6 , A q−5 , A q−4 , A q−3 , A q−2 , A q−1 , A q , A q+1 , A q+2 , A q+3 , A q+4 , A q+5 , A q+6 , A q+7 , A q+8 , A q+9 , or A q+10 of an HA1 domain;

wherein HA1 N-term is the N-terminal amino acid of a mature HA0 protein lacking a signal peptide; wherein HA1 C-term is the C-terminal amino acid of an HA1 domain; and wherein A p is the Cys that corresponds to amino acid position 52 of an HA1 domain using H3 numbering; and

wherein A q is the Cys that corresponds to amino acid position 277 of an HA1 domain using H3 numbering.

5. The chimeric influenza virus hemagglutinin (HA) polypeptide of claim 1 , wherein:

(a) the HA stem domain comprises (i) an HA1 N-terminal stem segment, wherein the HA1 N-terminal stem segment consists of amino acid residues HA1 N-term through A p−10 , A p−9 , A p−8 , A p−7 , A p−6 , A p−5 , A p−4 , A p−3 , A p−2 , A p−1 , A p , A p+1 , A p+2 , A p+3 , A p+4 , A p+5 , A p+6 , A p+7 , A p+8 , A p+9 , or A p+10 ; (ii) an HA1 C-terminal stem segment, wherein the HA1 C-terminal stem segment consists of amino acid residues A q−1 , A q−2 , A q−3 , A q−4 , A q , A q+1 , A q+2 , or A q+3 through HA1 C-term ; and (iii) an HA2 stem domain; and

(b) the HA globular head domain comprises the amino acid residues between (i) A p−10 , A p−9 , A p−8 , A p−7 , A p−6 , A p−5 , A p−4 , A p−3 , A p−2 , A p−1 , A p , A p+1 , A p+2 , A p+3 , A p+4 , A p+5 , A p+6 , A p+7 , A p+8 , A p+9 , or A p+10 and (ii) A q−1 , A q−2 , A q−3 , A q−4 , A q , A q+1 , A q+2 , or A q+3 of an HA1 domain; and

wherein HA1 N-term is the N-terminal amino acid of a mature HA0 protein lacking a signal peptide; wherein HA1 C-term is the C-terminal amino acid of an HA1 domain; and wherein Ap is the Cys that corresponds to amino acid position 52 of an HA1 domain using H3 numbering; wherein Aq is the Cys that corresponds to amino acid position 277 of an HA1 domain using H3 numbering.

6. The chimeric influenza HA polypeptide of claim 1 , wherein the polypeptide further comprises an HA influenza virus luminal domain, an influenza virus HA transmembrane domain, and an influenza virus HA cytoplasmic domain.

7. The chimeric influenza virus HA polypeptide of claim 6 , wherein the luminal domain, the transmembrane domain, and the cytoplasmic domain are from influenza virus A/California/4/2009 HA or influenza virus A/California/4/2009 (H1N1)-like influenza virus HA.

8. The chimeric influenza virus HA polypeptide of claim 3 , wherein the polypeptide further comprises a luminal domain, a transmembrane domain, and a cytoplasmic domain from influenza virus A/California/4/2009 HA or influenza virus A/California/4/2009 (H1N1)-like influenza virus HA.

9. The chimeric influenza virus HA polypeptide of claim 1 , wherein the polypeptide is soluble.

10. The chimeric influenza virus HA polypeptide of claim 9 , wherein the polypeptide comprises a trimerization domain.

11. The chimeric influenza virus HA polypeptide of claim 9 , wherein the polypeptide does not comprise a transmembrane domain or an endodomain of an influenza virus HA, and further comprises (i) a thrombin cleavage site and a T4 trimerization domain; (ii) a HIS tag, or both.

12. The chimeric influenza virus HA polypeptide of claim 1 , which is expressed and isolated from a mammalian cell or an insect cell.

13. A nucleic acid encoding the chimeric influenza virus hemagglutinin (HA) polypeptide of claim 1 .

14. A nucleic acid encoding the chimeric influenza virus hemagglutinin (HA) polypeptide of claim 3 .

15. A host cell expressing the nucleic acid of claim 13 .

16. A virus comprising: (a) a genome engineered to express a nucleic acid encoding the chimeric influenza virus HA polypeptide of claim 1 ; or (b) the chimeric influenza virus HA polypeptide of claim 1 .

17. The virus of claim 16 , which is an influenza A virus.

18. The virus of claim 16 , which is a vesicular stomatitis virus (VSV), Newcastle disease virus (NDV), adenovirus, or baculovirus.

19. An embryonated egg or cell line comprising the virus of claim 16 .

20. A method for producing the chimeric influenza virus HA polypeptide of claim 1 , comprising (a) culturing a cell or cell line expressing the chimeric influenza virus HA polypeptide of claim 1 ; and (b) isolating the chimeric influenza virus HA polypeptide.

21. A method for producing the virus of claim 16 , comprising (a) propagating the virus of claim 16 in an embryonated egg; and (b) isolating the virus from the embryonated egg.

22. An immunogenic composition comprising the chimeric influenza virus HA polypeptide of claim 1 .

23. An immunogenic composition comprising the virus of any one of claim 16 .

24. The immunogenic composition of claim 22 further comprising an adjuvant.

25. The immunogenic composition of claim 24 , wherein the adjuvant is an aluminum salt, 3 De-O-acylated monophosphoryl lipid A, MF59, AS03, AS04, polysorbate 80, an imidazopyridine compound, an imidazoquinoxaline compound, Matrix-M, MVA, ISCOMATRIX, AddaVax, polyI:C, in vitro transcribed RNA hairpin from Sendai virus Cantell strain defective interfering RNA, a saponin, Freund's adjuvant, an oil in water emulsion, CpG, a physical adjuvant, or a Toll-like receptor stimulatory molecule.

26. A method of immunizing a subject against influenza virus comprising administering to the subject an effective amount of the immunogenic composition of claim 22 .

27. A method of preventing an influenza virus disease in a subject comprising administering to the subject an effective amount of the immunogenic composition of claim 22 .

28. A method of immunizing a subject against influenza virus comprising administering to the subject an effective amount of the immunogenic composition of claim 23 .

29. A method of preventing an influenza virus disease in a subject comprising administering to the subject an effective amount of the immunogenic composition of claim 23 .

30. The method of claim 26 , wherein the subject is human.

31. The method of claim 27 , wherein the subject is human.

32. The method of claim 28 , wherein the subject is human.

33. The method of claim 29 , wherein the subject is human.