Impact of host cell line adaptation on quasispecies composition and glycosylation of influenza A virus hemagglutinin.

The genome of influenza A viruses is constantly changing (genetic drift) resulting in small, gradual changes in viral proteins. Alterations within antibody recognition sites of the viral membrane glycoproteins hemagglutinin (HA) and neuraminidase (NA) result in an antigenetic drift, which requires the seasonal update of human influenza virus vaccines. Generally, virus adaptation is necessary to obtain sufficiently high virus yields in cell culture-derived vaccine manufacturing.