Pre-fusion rsv f antigens

Abstract

The invention relates to pre-fusion RSV F protein and polypeptides that contain one or more amino acid mutations that stabilize the pre-fusion conformation or destabilize the post-fusion conformation. The invention also relates to methods for inducing an immune response to pre-fusion RSV F.

1 . A pre-fusion respiratory syncytial virus (RSV) F polypeptide comprising at least two introduced cysteine residues, wherein said cysteines are in close proximity to one another and form an intrachain disulfide bond that stabilizes the pre-fusion RSV F polypeptide. 
     
     
         2 . The pre-fusion RSV F polypeptide of  claim 1 , wherein said cysteine mutations are not more than about 10 Å away from each other. 
     
     
         3 . The pre-fusion RSV F polypeptide of  claim 1 , wherein:
 the HRB region and the DI and/or DII region contain an introduced cysteine residue, and a disulfide bond is formed between the introduced cysteine residue in the HRB region and the introduced cysteine residue in the DI or DII region;   (ii) the HRA region and the DIII region contain an introduced cysteine residue, and a disulfide bond is formed between the introduced cysteine residues in the HRA region and the DIII region; or   (iii) the HRA region contains at least two introduced cysteine residues, and a disulfide bond is formed between the introduced cysteine residues in the HRA region.   
     
     
         4 . (canceled) 
     
     
         5 . (canceled) 
     
     
         6 . A pre-fusion respiratory syncytial virus (RSV) F polypeptide comprising a post-fusion modification selected from the group consisting of deletion of the HRA helix, deletion of the HRB helix, introduction of point mutations, addition of glycosylation sites and combinations thereof, wherein said post-fusion modification destabilizes the post-fusion conformation. 
     
     
         7 . The pre-fusion RSV F polypeptide of  claim 6 , wherein said destabilizing post-fusion modification is deletion of the HRB helix. 
     
     
         8 . The pre-fusion RSV F polypeptide of  claim 7 , further comprising deletion of the fusion peptide. 
     
     
         9 . The pre-fusion RSV F polypeptide of  claim 6 , wherein said destabilizing post-fusion modification is addition of a glycosylation site. 
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . The pre-fusion RSV F polypeptide of  claim 1 , wherein the pre-fusion RSV F polypeptide is a soluble ectodomain of RSV F or a trimer of soluble ectodomain of RSV F. 
     
     
         13 . A chimeric pre-fusion F protein comprising a stabilized F protein from a virus other than RSV that contains one or more neutralizing epitope of RSV F. 
     
     
         14 . The chimeric pre-fusion F protein of  claim 13 , wherein said stabilized F protein is:
 from a parainfluenza virus F polypeptide or a metapneumovirus virus F polypeptide;   (ii) a PIV5 pre-fusion F polypeptide or a NDV pre-fusion F polypeptide; or   (iii) a soluble ectodomain.   
     
     
         15 . (canceled) 
     
     
         16 . (canceled) 
     
     
         17 . The chimeric pre-fusion F protein of  claim 13 , wherein said neutralizing epitopes of RSV F are from the HRA region of RSV F. 
     
     
         18 . The chimeric pre-fusion F protein of  claim 13 , wherein the neutralizing epitopes are selected from the group consisting of the epitopes that are recognized by motavizumab, palivizumab, mAb 11, mAb 151, mAb 1129, mAb 1153, mAb 1200, mAb 1214, mAb 1237, mAb 47F, mAb 7C2, mAb B4, Fab 19, mAb AK13A2, mAb 7.936, mAb 9.936, mAb 19, mAb 20, mAb 101F and combinations thereof. 
     
     
         19 . The pre-fusion RSV F polypeptide of  claim 1 , further comprising a heterologous oligomerization domain, an epitope, or a signal peptide. 
     
     
         20 . The pre-fusion RSV F polypeptide of  claim 19 , wherein said heterologous oligomerization domain is a trimerization domain. 
     
     
         21 . The pre-fusion RSV F polypeptide of  claim 20  wherein the trimerization domain is from influenza hemagglutinin, SARS spike, HIV gp41, NadA, modified GCN4, GCN4 or ATCase. 
     
     
         22 . An immunogenic composition comprising the pre-fusion RSV F polypeptide of  claims 1 . 
     
     
         23 . The immunogenic composition of  claim 22 , wherein said composition further comprises an adjuvant. 
     
     
         24 . The immunogenic composition of  claim 23 , wherein the adjuvant is selected from the group consisting of: an aluminum salt, a squalene-in-water emulsion, a benzonaphthyridine compound, a phospholipid compound, a small molecule immunopotentiator and combinations of any of the foregoing. 
     
     
         25 . An isolated nucleic acid encoding the pre-fusion RSV F polypeptide of  claim 1 . 
     
     
         26 . The isolated nucleic acid of  claim 25 , which is a self-replicating RNA molecule. 
     
     
         27 . An immunogenic composition comprising the self-replicating RNA molecule of  claim 26 . 
     
     
         28 . The immunogenic composition of  claim 27 , further comprising an RNA delivery system. 
     
     
         29 . A method of inducing an immune response to RSV F in a subject comprising administering an immunogenic composition of  claim 22  to the subject. 
     
     
         30 . A method of inducing an immune response to RSV F in a subject comprising administering an immunogenic composition of  claim 27  to the subject.