The present invention provides, among other things, a novel and improved method for generating mosaic influenza antigenic polypeptides including hemagglutinin (HA) and neuraminidase (NA) polypeptides based on unique combination of epitope patterns that maximize exposure to epitopes present across multiple HA or NA sequences and therefore improved influenza strain coverage. In particular, the present invention provides engineered H1N1 influenza hemagglutinin (HA) polypeptides that are comprised of novel combinations of protective epitopes and antigenic regions from multiple H1N1 viral strains. Such engineered HA polypeptides have improved properties over HA polypeptides developed through conventional approaches that rely on consensus alignments of viral sequences.

The invention provides compositions and methods useful to prepare segmented, negative strand RNA viruses, e.g., orthomyxoviruses such as influenza A viruses, entirely from cloned cDNAs and in the absence of helper virus.

A method for adapting an influenza virus to Vero cells is provided. The method comprises infecting Vero cells with the influenza virus, cultivating the infected Vero cells, harvesting influenza viruses of each passage, wherein infectious dose of the influenza viruses of one passage is greater than or equal to infectious dose of the influenza viruses of a previous passage. The present disclosure also relates to a composition. Said composition comprises polyriboinosinic acid-polyribocytidylic acid, at least one antibiotic or polyamide compound, at least one positive ion, influenza viruses and/or influenza antigens, wherein said influenza viruses and/or influenza antigens are acquired from Vero cell adapted influenza viruses.

Disclosed are compositions and methods for increasing influenza virus production.

The invention relates to the field of veterinary medicine. The invention provides an immunogenic composition, comprising a hemagglutinin protein of avian influenza virus H5 subtype. Also provided is a method of differentiating animals naturally infected with AIV from animals vaccinated with the immunogenic composition of the invention. The immunogenic composition of the invention can provide a broader, more effective, long-lasting and early onset protection on poultry.

The present invention relates to the production of modified influenza viral proteins in plants. More specifically, the present invention relates to producing and increasing influenza virus-like particle (VLP) production in plants, wherein the VLPs comprise the modified influenza viral proteins, such as modified influenza hemagglutinin (HA). The HA protein may comprising an amino acid sequence comprising at least one substitution when compared to a corresponding wildtype amino acid sequence. Further provided are nucleic acid encoding the modified HA protein. Furthermore methods of producing an influenza virus like particle (VLP) and methods of increasing yield of production of an influenza virus like particle (VLP) in a plant, portion of a plant, or a plant cell, are also provided.

Described herein is a method of enhancing virus replication in permissive cells that express a receptor to FGF2 protein. The method includes administering FGF2 protein or a functional variant thereof and the virus to the permissive cells. An oncolytic virus having a genome that includes an open reading frame that encodes FGF2 protein or a functional variant thereof is also described.

The invention provides a composition useful to prepare high titer influenza viruses, e.g., in the absence of helper virus, which includes internal genes from an influenza virus vaccine strain or isolate, e.g., one that is safe in humans, for instance, one that does not result in significant disease, and genes from vaccine seed virus isolates which include a HA gene segment with a HA2 sequence encoding a HA2 that confers enhanced growth in cells in culture, such as Vero cells.

Described herein is a method of enhancing virus replication in permissive cells that express a receptor to FGF2 protein. The method includes administering FGF2 protein or a functional variant thereof and the virus to the permissive cells. An oncolytic virus having a genome that includes an open reading frame that encodes FGF2 protein or a functional variant thereof is also described.

An isolated recombinant influenza virus is provided having PA, PB1, PB2, NP, NS, M, NA and HA viral segments, wherein the PB1 viral segment encodes a PB1 with a residue other than isoleucine at position 711 or the M viral segment encodes a M1 with a residue other than methionine at position 128, wherein the recombinant influenza virus has enhanced replication relative to a corresponding influenza virus having a PB1 viral segment that encodes a PB1 with an isoleucine at position 711 or having a M viral segment that encodes a M1 with methionine at position 128, as well as methods of making and using the virus.