title: Relationship between surface antigens of two variants of influenza A (H3N2) virus, as revealed by hemagglutination inhibition, kinetic neutralization, and neuraminidase inhibition.
abstract: Rabbit antisera were raised against plaque-purified influenza virus strains of A/Victoria/75 and A/Texas/77 isolated from Seattle influenza patients. The antigenic specificity of hemagglutinins was compared by hemagglutination inhibition (HI) and kinetic neutralization tests. Anti-A/Victoria/75 had equally high HI titers and neutralization rate constants (kappa values) for A/Victoria/75 and A/Texas/77. In contrast, anti-A/Texas/77 had a high HI titer and kappa value to A/Texas/77 and a low HI titer and kappa value to A/Victoria/75. Similar results were obtained with antisera to recombinants with hemagglutinin specific for A/Victoria/3/75 or A/Texas/1/77 and with irrelevant neuraminidase. Seven wild-type isolates, three each of A/Texas and A/Victoria, and one strain characterized as a bridging strain were tested by HI and kinetic neutralization. Characterization as A/Texas or A/Victoria was confirmed by the results. No significant difference in neuraminidase specific for A/Victoria/75 or A/Texas/77 was hown when recombinants with an irrelevant hemagglutinin were compared by the neuraminidase inhibition test. These results suggest that A/Victoria/75 strains are "senior" to A/Texas/77 strains. The epidemiological implications of this observation are discussed.
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis*; D000956:Antigens, Viral / Q000032:analysis*; D004285:Dogs; D006389:Hemagglutinins, Viral / Q000276:immunology; D053122:Influenza A Virus, H3N2 Subtype; D009980:Influenza A virus / Q000276:immunology*; D007700:Kinetics; D009439:Neuraminidase / Q000037:antagonists & inhibitors
chemical_list: D000954:Antigens, Surface; D000956:Antigens, Viral; D006389:Hemagglutinins, Viral; D009439:Neuraminidase