Provided are compounds of Formula (II) that enhance the efficacy of viruses by increasing spread of the virus in cells, increasing the titer of virus in cells, or increasing the antigen expression from a virus, gene or trans-gene expression from a virus, or virus protein expression in cells. Other uses, compositions and methods of using same are also provided. ##STR00001##

The present invention refers to a process for purifying virus particles from cell culture, comprising the steps of subjecting the cell culture to centrifugation to get a supernatant fraction of virus particles, incubating said fraction with a nuclease, diluting the fraction with low conductivity buffer, subjecting said diluted fraction to a SO3 chromatography step, performing a washing step with low conductivity buffer, and eluting virus particles.

Modified influenza virus neuraminidases are described herein that have stabilized NA tetramers which may improve vaccine production efficiency, thus improving the yield of vaccine viruses.

A method of producing a virus like particle (VLP) in a plant comprising modified H3 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. 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.

Provided is a method for efficiently proliferating an influenza virus serving as a material for vaccine in a host.

A method for proliferating an influenza virus in a host, comprising a step of inhibiting transfer of Bax in a host cell to the inner mitochondrial membrane.

A transkingdom platform for the delivery of therapeutic nucleic acids to epithelial tissues where the nucleic acids are designed to have enhanced stability. The platform offers numerous improvements to prior delivery platforms including expression of the double-stranded RNA binding domain (dsRBD) domains of TAR RNA binding protein (TRBP), knockout of RNase R activity in the bacterial delivery vehicle, and expression of the methyltransferase gene, HEN1, for simultaneous packaging with a therapeutic nucleic acid delivery vehicle.

Disclosed are compositions and methods comprising one or more recombinant influenza viruses. Recombinant influenza viruses with mutated polymerases and/or rearranged genomes are disclosed. Constructs comprising different influenza nucleic acid sequences are also provided. Methods of inducing protecting immunity with the recombinant influenza viruses are disclosed. Also disclosed are methods of plasmid-free production of influenza virus comprising amplicons comprising one or more of influenza genes.

It is provided a method for manufacturing viruses in an in vitro cell culture. The method comprising the following steps: providing a cell culture of avian epithelial cells chosen from at least one of the cell cultures deposited under deposition numbers DSM ACC3345, DSM ACC3346, DSM ACC3347, DSM ACC3348, DSM ACC3349 at Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen and Zellkulturen GmbH on Dec. 12, 2018; infecting at least some of the cells in the cell culture with virus particles; incubating the cells for a first period of time; and recovering viruses produced by the cell culture from a supernatant of the cell culture.

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

The present invention relates to methods of replicating viruses in vitro. In particular, the invention relates to a genetically modified population of cells, and/or a population of cells treated with an exogenous compound, wherein the cells are capable of producing more virus than cells lacking the genetic modification and/or lacking treatment with the exogenous compound. The invention also relates to methods of producing populations of such cells, as well as the use of the viruses obtained to prepare vaccine compositions.