Disclosed herein are methods for increasing protein yield and cellular productivity. Chemical agents facilitate host cell production of biological molecules to increase product yield.

Compositions and methods to prepare influenza virus-like particles (VLPs) are provided.

The present invention provides a method for purifying virus particles from host cells infected with virus, wherein the virus particles are treated with benzonase and polyethylene glycol and the use of said purified viruses for therapeutic compositions.

Disclosed is an adapted Madin-Darby canine kidney cell line capable of suspension culture in the absence of serum, and a chemically-defined medium for culture of the adapted MDCK cell line. Further disclosed are culture methods for growing the adapted MDCK cell line and methods for producing a vaccine from the adapted MDCK cell line grown in the chemically-defined medium.

Disclosed herein are nanoparticles suitable for use in vaccines. The nanoparticles present antigens from pathogens surrounded to and associated with a detergent core resulting in enhanced stability and good immunogenicity. Dosages, formulations, and methods for preparing the vaccines and nanoparticles are also disclosed.

The invention provides a composition useful to prepare influenza viruses, e.g., in the absence of helper virus, using vectors which include tandem transcription cassettes containing PolI and/or PolII promoters.

A method of producing a virus like particle (VLP) in a plant comprising modified hemagglutinin is provided. The method comprises introducing a nucleic acid comprising a regulatory region active in the plant and operatively linked to a nucleotide sequence encoding a modified influenza hemagglutinin (HA) protein into the plant, or portion of the plant, the modified HA protein comprises a modified proteolytic loop. Followed by incubating the plant or portion of the plant under conditions that permit the expression of the nucleic acids, thereby producing the VLP. The modified proteolytic loop may comprise one or more protease cleavage sites exhibiting reduced or abolished cleavage by a protease. The nucleotide sequence encoding the HA may be selected from the group consisting of B HA, C, H1, H2, H3, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, and H16. Also described is a virus like particle (VLP) produced by the method, and plants expressing the VLP. The virus like particle (VLP) may comprise plant-specific N-glycans, or modified N-glycans.

The present invention concerns a method for production of an active ingredient of a drug or diagnostic agent, in which (a) MDCK cells are infected with a virus; and (b) the MDCK cells are cultured in suspension culture on a commercial scale under conditions that permit multiplication of the viruses; in which culturing occurs in a volume of at least 30 L. The invention also concerns a method for production of a drug or diagnostic agent in which an active ingredient is produced according to the above method and mixed with an appropriate adjuvant, auxiliary, buffer, diluent or drug carrier.

The disclosure provides combination mRNA vaccines for respiratory viruses, as well as methods of using the vaccines.

New influenza donor strains for the production of reassortant influenza B viruses are provided.