[Selection of antigenic variants of H1N1 influenza viruses by means of monoclonal antibodies].

Six different monoclonal antibodies to influenza A/Brazil/11/78 virus hemagglutinin were used for selection of antigenic variants of H1N1 viruses: A/USSR/090/77 and A/black-headed gull/ Kaz . SSR/470/79. The group-specific monoclonal antibody completely neutralized the infective activity of the parental viruses (dilutions 1:5 to 1:640). Two antigenic variants of wild type viruses were obtained using cross-reactive antibody. A comparative study of the antigenic structure, biological properties, and peptide maps of the heavy chain of the original viruses, antigenic variants, and some epidemic H1N1 strains was carried out. The selected variants of A/black-headed gull/ Kaz . SSR/470/77 and A/USSR/090/79 viruses were shown to be similar to epidemic H1N1 strains isolated in 1953 and 1978.