| 摘要 |
PROBLEM TO BE SOLVED: To provide methods for producing influenza viruses in cell culture, the viruses suitable as recombinant influenza vaccines, using a bi-directional expression vector for the use in a multi plasmid influenza virus expression system.SOLUTION: A method of producing a temperature-sensitive influenza virus includes the steps of: introducing at least one mutation, resulting in amino acid substitutions at specific positions, into an influenza B virus genome; and replicating the mutated influenza virus genome under conditions whereby the virus is produced. |
