title: Performance characteristics of qualified cell lines for isolation and propagation of influenza viruses for vaccine manufacturing.
abstract: Cell culture is now available as a method for the production of influenza vaccines in addition to eggs. In accordance with currently accepted practice, viruses recommended as candidates for vaccine manufacture are isolated and propagated exclusively in hens' eggs prior to distribution to manufacturers. Candidate vaccine viruses isolated in cell culture are not available to support vaccine manufacturing in mammalian cell bioreactors so egg-derived viruses have to be used. Recently influenza A (H3N2) viruses have been difficult to isolate directly in eggs. As mitigation against this difficulty, and the possibility of no suitable egg-isolated candidate viruses being available, it is proposed to consider using mammalian cell lines for primary isolation of influenza viruses as candidates for vaccine production in egg and cell platforms. To investigate this possibility, we tested the antigenic stability of viruses isolated and propagated in cell lines qualified for influenza vaccine manufacture and subsequently investigated antigen yields of such viruses in these cell lines at pilot-scale. Twenty influenza A and B-positive, original clinical specimens were inoculated in three MDCK cell lines. The antigenicity of recovered viruses was tested by hemagglutination inhibition using ferret sera against contemporary vaccine viruses and the amino acid sequences of the hemagglutinin and neuraminidase were determined. MDCK cell lines proved to be highly sensitive for virus isolation. Compared to the virus sequenced from the original specimen, viruses passaged three times in the MDCK lines showed up to 2 amino acid changes in the hemagglutinin. Antigenic stability was also established by hemagglutination inhibition titers comparable to those of the corresponding reference virus. Viruses isolated in any of the three MDCK lines grew reasonably well but variably in three MDCK cells and in VERO cells at pilot-scale. These results indicate that influenza viruses isolated in vaccine certified cell lines may well qualify for use in vaccine production.
authors: Ruben O
authors: RO
authors: Donis
authors: C Todd
authors: CT
authors: Davis
authors: Angie
authors: A
authors: Foust
authors: M Jaber
authors: MJ
authors: Hossain
authors: Adam
authors: A
authors: Johnson
authors: Alexander
authors: A
authors: Klimov
authors: Rosette
authors: R
authors: Loughlin
authors: Xiyan
authors: X
authors: Xu
authors: Theodore
authors: T
authors: Tsai
authors: Simone
authors: S
authors: Blayer
authors: Heidi
authors: H
authors: Trusheim
authors: Tony
authors: T
authors: Colegate
authors: John
authors: J
authors: Fox
authors: Beverly
authors: B
authors: Taylor
authors: Althaf
authors: A
authors: Hussain
authors: Ian
authors: I
authors: Barr
authors: Chantal
authors: C
authors: Baas
authors: Jaap
authors: J
authors: Louwerens
authors: Ed
authors: E
authors: Geuns
authors: Min-Shi
authors: MS
authors: Lee
authors: Odewijk
authors: O
authors: Venhuizen
authors: Elisabeth
authors: E
authors: Neumeier
authors: Thedi
authors: T
authors: Ziegler
mesh_terms: D000818:Animals; D000940:Antigenic Variation; D000956:Antigens, Viral / Q000276:immunology*; D002522:Chlorocebus aethiops; D004285:Dogs; D005289:Ferrets; D006385:Hemagglutination Inhibition Tests; D053118:Influenza A Virus, H1N1 Subtype; D053122:Influenza A Virus, H3N2 Subtype; D061985:Madin Darby Canine Kidney Cells / Q000821:virology*; D009975:Orthomyxoviridae / Q000254:growth & development*; D014709:Vero Cells; D014776:Virus Cultivation
chemical_list: D000956:Antigens, Viral
keywords: Antigenic stability; Genetic stability; Influenza vaccines; MDCK; VERO; Vaccine-certified cell lines; Virus isolation; Virus purification