Influenza vaccine strain selection: equivalence of two antigenically distinct haemagglutinin variants of 1989 H3N2 influenza A virus in protection of mice.
Precise antigenic analysis with haemagglutinin-inhibition (HI) tests of 1989 H3N2 influenza A viruses with polyclonal ferret, rabbit and mouse antisera has shown, first, significant differences among 1989 wild-type isolates, second, antigenic differences between two high-yield vaccine candidate reassortant viruses, third, significant antigenic differences of one reassortant (X-105) from the wild-type virus (A/Guangdong A/39) from which it was derived, and fourth, dependence of antigenic characterization of viruses upon the host species used in immunization. Nevertheless, the two reassortant viruses (only 43% similar by HI test) were equally protective in preventing homovariant or heterovariant infection in either previously unimmunized or infection-primed mice. These results not only confirm the known antigenic heterogeneity of influenza A viruses, but raise questions about the adequacy of current methods of antigenic characterization of influenza viruses and the basis for decisions on vaccine strain selection.
Johansson
B E
BE
Department of Microbiology, Mount Sinai School of Medicine, City University of New York, NY 10029.
Kilbourne
E D
ED
D000818:Animals; D000956:Antigens, Viral / Q000302:isolation & purification; D005260:Female; D006389:Hemagglutinins, Viral / Q000276:immunology*; D053122:Influenza A Virus, H3N2 Subtype; D009980:Influenza A virus / Q000145:classification / Q000276:immunology*; D007252:Influenza Vaccines / Q000302:isolation & purification*; D051379:Mice; D008807:Mice, Inbred BALB C; D009976:Orthomyxoviridae Infections / Q000517:prevention & control; D013045:Species Specificity; D013810:Therapeutic Equivalency
D000956:Antigens, Viral; D006389:Hemagglutinins, Viral; D007252:Influenza Vaccines