title: Cell-based assay for the determination of temperature sensitive and cold adapted phenotypes of influenza viruses.
abstract: The determination of temperature sensitive (ts) and cold adapted (ca) phenotype for influenza A and B strains has been conducted traditionally using embryonated chicken eggs. As attempts are made to move away from the use of eggs in the manufacturing process of influenza vaccines, it will become useful to develop cell-based assays to support cell culture-based vaccine production. In this study, MDCK cells have been evaluated as a tool for determining the ts and ca phenotypes associated with live attenuated influenza viruses. Direct comparisons were made of these phenotypes carried out in eggs. Reassortants made from the Russian live attenuated influenza donor strains A/Leningrad/134/17/57 (H2N2) and B/USSR/60/69 were prepared entirely in MDCK cells and their phenotypes evaluated using the MDCK cell-based assay. It is concluded that MDCK cells are more sensitive than eggs for the measurement of ts and ca phenotype of influenza viruses (particularly for influenza A) and they provide an alternative means for screening candidate reassortants prior to determining their genome composition.
authors.affiliation: Department of Virus and Cell Biology, Merck & Co Inc, 770 Sumneytown Pike, WP44L-206B, West Point, PA 19486, USA.
authors.forename: I
authors.initials: I
authors.lastname: Kiseleva
authors.forename: Q
authors.initials: Q
authors.lastname: Su
authors.forename: T J
authors.initials: TJ
authors.lastname: Toner
authors.forename: C
authors.initials: C
authors.lastname: Szymkowiak
authors.forename: W-S
authors.initials: WS
authors.lastname: Kwan
authors.forename: L
authors.initials: L
authors.lastname: Rudenko
authors.forename: A R
authors.initials: AR
authors.lastname: Shaw
authors.forename: R
authors.initials: R
authors.lastname: Youil
mesh_terms: D000818:Animals; D002460:Cell Line; D002642:Chick Embryo; D003080:Cold Temperature; D004285:Dogs; D009980:Influenza A virus / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D009981:Influenza B virus / Q000472:pathogenicity / Q000502:physiology*; D007252:Influenza Vaccines; D010641:Phenotype; D016865:Reassortant Viruses / Q000235:genetics / Q000502:physiology*; D013696:Temperature; D014613:Vaccines, Attenuated; D014779:Virus Replication
chemical_list: D007252:Influenza Vaccines; D014613:Vaccines, Attenuated