Multi plasmid system for the production of influenza virus

摘要

Vectors and methods for the production of influenza viruses suitable as recombinant influenza vaccines in cell culture are provided. Bi-directional expression vectors for use in a multi-plasmid influenza virus expression system are provided. Additionally, the invention provides methods of producing influenza viruses with enhanced ability to replicate in embryonated chicken eggs and/or cells (e.g., Vero and/or MDCK) and further provides influenza viruses with enhanced replication characteristics. A method of producing a cold adapted (ca) influenza virus that replicates efficiently at, e.g., 25° C. (and immunogenic compositions comprising the same) is also provided.

主权项

1. An isolated reassortant influenza B virus, comprising:
a NP polypeptide comprising a threonine at position 55, an alanine at position 114, a histidine at position 410, and a threonine at position 509; a PA polypeptide comprising a methionine at position 431; and a PB2 polypeptide comprising an arginine at position 630; wherein:the isolated reassortant influenza B virus has a temperature sensitive phenotype and a cold-adapted phenotype, andthe positions in the NP polypeptide, the PA polypeptide and the PB2 polypeptide correspond to positions in full-length NP, PA and PB2 polypeptides of B/Ann Arbor/1/66.