title: Direct isolation in eggs of influenza A (H1N1) and B viruses with haemagglutinins of different antigenic and amino acid composition.
abstract: Influenza A (H1N1) and influenza B viruses from clinical samples were isolated in the amniotic cavity of embryonated hens' eggs by classical techniques and propagated in the allantoic cavity. Virus progeny from different eggs which had been inoculated with virus material from the same clinical sample possessed antigenically distinguishable haemagglutinins (HAs). Virus progeny of some eggs possessed HAs which were serologically identical to those of virus isolated in parallel in mammalian (MDCK) cells. These egg-grown viruses possessing HAs with the antigenic phenotype of mammalian cell-grown viruses appeared to be antigenically related to epidemic influenza virus because post-infection human sera reacted to high titre with the virus HA. Specific nucleotide changes were detected in the HAs of the viruses isolated directly in eggs at positions 163 and 189 for influenza A (H1N1) viruses or positions 141 and 196 to 198 for influenza B viruses. Egg-isolated viruses which possessed the antigenic phenotype of mammalian cell-grown viruses retained glycosylation sites at positions 163 and 196. The viruses isolated directly in embryonated hens' eggs which possessed the HA antigenic phenotype and glycosylation sites of MDCK cell-grown virus can, unlike the latter viruses themselves, be used as candidate influenza vaccine viruses.
authors.affiliation: Department of Medical Microbiology, London Hospital Medical College, Whitechapel, U.K.
authors.forename: J S
authors.initials: JS
authors.lastname: Oxford
authors.forename: R
authors.initials: R
authors.lastname: Newman
authors.forename: T
authors.initials: T
authors.lastname: Corcoran
authors.forename: J
authors.initials: J
authors.lastname: Bootman
authors.forename: D
authors.initials: D
authors.lastname: Major
authors.forename: P
authors.initials: P
authors.lastname: Yates
authors.forename: J
authors.initials: J
authors.lastname: Robertson
authors.forename: G C
authors.initials: GC
authors.lastname: Schild
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000302:isolation & purification*; D002460:Cell Line; D002642:Chick Embryo; D006389:Hemagglutinins, Viral / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D053118:Influenza A Virus, H1N1 Subtype; D009980:Influenza A virus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D009981:Influenza B virus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D010641:Phenotype
chemical_list: D000956:Antigens, Viral; D006389:Hemagglutinins, Viral