Multi plasmid system for the production of influenza virus
AssigneeMedImmune, LLC
InventorsErich Hoffmann, Hong Jin, George Kemble, Zhongying Chen
Life of this patent
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Abstract
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.
Claims21
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, and
- the 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.
A method for making a reassortant influenza B virus, comprising:
- (a) introducing mutations in an influenza B virus genome that result in (i) 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;
- (ii) a PA polypeptide comprising a methionine at position 431;
- and (iii) a PB2 polypeptide comprising an arginine at position 630;
- (b) introducing a plurality of vectors into a population of cultured host cells, wherein the plurality of vectors corresponds to the influenza B virus genome and the plurality of vectors comprises the mutations recited in (a);
- (c) culturing the population of host cells;
- and
- (d) recovering the reassortant influenza B virus produced by the host cells of step (c), wherein:
- the reassortant influenza B virus has a temperature sensitive phenotype and a cold-adapted phenotype, and
- the 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.
Dependencies are inferred from the claim text.