A method for synthesizing influenza virus-like particles (VLPs) within a plant or a portion of a plant is provided. The method involves expression of influenza HA in plants and the purification by size exclusion chromatography. The invention is also directed towards a VLP comprising influenza HA protein and plant lipids. The invention is also directed to a nucleic acid encoding influenza HA as well as vectors. The VLPs may be used to formulate influenza vaccines, or may be used to enrich existing vaccines.

A method for producing reassortant influenza viruses is provided. Also provided are reassortant influenza viruses produced according to the method, as well as vaccines based on said reassortant influenza viruses.

Disclosed herein are methods and composition producing a viral vaccine with reduced particle size, particularly for use in the production of influenza virus vaccines.

In a first aspect, the present invention relates to a method for the purification of virus compositions as well as biological macromolecular compounds in a sample comprising mixing the sample with osmolytes, like non-ionic organic polymers and contacting the mixed sample with a hydrophilic membrane, optionally washing the membrane, and eluting the virus preparations or biological macromolecular components from the membrane with an eluting solution containing reduced amounts or no osmolytes, like non-ionic organic polymer. Moreover, virus compositions and biological macromolecular components obtainable with the method according to the present invention are provided as well as the use of the method according to the present invention for purification of virus compositions including whole virus particles and virus-like particles or biological macromolecular components.

The present invention relates to an influenza virus production method using a disposable culture process system, and a test for quickly checking conditions for influenza virus antigen purification. According to the present invention, conditions for influenza surface antigen obtainment (purification) may be quickly and reliably checked according to the unique method of the present invention, even without using the single radial immunodiffusion technique which is conventionally used as a standard test method when producing influenza vaccines, and thus the production time for an influenza surface antigen subunit vaccine is notably reduced, thereby enabling quick response as a result of rapid vaccine development/manufacturing, even in a rapid novel influenza pandemic situation. In addition, according to the influenza virus production method of the present invention, culture media exchange may be carried out in an airtight system by using a continuous low-speed centrifuge using a disposable bag, and thus the possibility of contamination occurring during the virus production process may be greatly reduced.

Disclosed herein are compositions and methods related to mutant viruses, and in particular, mutant influenza viruses. The mutant viruses disclosed herein include a mutant M2 sequence, and are useful in immunogenic compositions, e.g., as vaccines. Also disclosed herein are methods, compositions and cells for propagating the viral mutants, and methods, devices and compositions related to vaccination.

The present disclosure discloses a whole avian-origin reverse genetic manipulation system and its use in producing a recombinant H7N9 avian influenza vaccine. The whole avian-origin reverse genetic manipulation system is an eight-plasmid reverse genetic manipulation system based on H5N2 subtype avian influenza D7 virus strain, which is comprised of 8 recombinant plasmids respectively containing PB2, PB1, PA, HA, NP, NA, M and NS gene fragments derived from H5N2 subtype avian influenza D7 virus strain. The genome of the recombinant H7N9 subtype avian influenza vaccine of the present disclosure is comprised of an NA gene and a modified HA gene derived from a highly pathogenic H7N9 subtype avian influenza virus strain, as well as PB2, PB1, PA, NP, M and NS genes derived from H5N2 subtype avian influenza D7 virus strain.

Provided is an application of a label gene sequence in the preparation of an H9 avian influenza vaccine strain which differentiates influenza A virus infection from vaccination, the label gene sequence containing a DNA sequence for coding an influenza B virus NA protein extracellular region amino acid sequence. Also provided are an H9 avian influenza vaccine strain which differentiates influenza A virus infection from vaccination, a preparation method therefor, and an application.

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.

The present disclosure discloses a whole avian-origin reverse genetic manipulation system and its use in producing a recombinant H7N9 avian influenza vaccine. The whole avian-origin reverse genetic manipulation system is an eight-plasmid reverse genetic manipulation system based on H5N2 subtype avian influenza D7 virus strain, which is comprised of 8 recombinant plasmids respectively containing PB2, PB1, PA, HA, NP, NA, M and NS gene fragments derived from H5N2 subtype avian influenza D7 virus strain. The genome of the recombinant H7N9 subtype avian influenza vaccine of the present disclosure is comprised of an NA gene and a modified HA gene derived from a highly pathogenic H7N9 subtype avian influenza virus strain, as well as PB2, PB1, PA, NP, M and NS genes derived from H5N2 subtype avian influenza D7 virus strain.