Preparation of influenza B virus recombinant strains.

The study of antigenic and biologic properties of influenza B epidemic viruses isolated in 1979 and 1983 and laboratory strain B/Lee/40 has revealed some differences in their biologic properties. The most marked changes have been found in the haemagglutinin (HA) and neuraminidase (NA) indicating that influenza B viruses underwent dramatic antigenic drifts during the period in question. The strains obtained by genetic recombination have inherited surface antigens of epidemic influenza B/Singapore/222/79 and B/USSR/100/83 viruses and preserved the HA thermolability inherent to these viruses.

[Characteristics of the biological and antigenic properties of reference strains of the influenza B virus at various periods of isolation].

The results of a comparative analysis of biological and antigenic properties of reference influenza B virus strains, B/Lee/40, B/Singapore/222/79, and B/USSR/100/83, are presented. The most marked changes were found in the antigenic properties of hemagglutinin and neuraminidase. Hemagglutinins of the strains under study were found to have both common antigens and qualitatively different strain-specific determinants.

Influenza virus antigens conjugated with a synthetic polyelectrolyte: a novel model of vaccines.

Haemagglutinin (HA), a mixture of haemagglutinin and neuraminidase (HA + NA), and matrix (M) protein were isolated from the influenza A virus and covalently coupled to a synthetic polyelectrolyte (P). A single injection into mice of the resultant conjugates (virogates) brought about efficient stimulation of the primary immune response specific to the corresponding viral antigens. Mice immunized with virogates HA.

[Immunogenic properties of epidemic and recombinant strains of influenza viruses H1N1 and H3N2].

The study of the immunogenic properties of epidemic influenza viruses H1N1 and H3N2 isolated from patients in 1979-1982 revealed a high immunogenic activity of H3N2 viruses. Recombinant strains of both subtypes (H1N1 and H3N2) had a higher immunogenicity than the original viruses. The intensity of immunity determined for an antigenically close pathogenic strain was considerably higher than for an antigenically remote pathogenic virus which is important for obtaining accurate information on the immunogenic activity of influenza viruses.

[Combined use of interferon inducers and recombinant influenza viruses for protection from the disease].

The data on the use of national interferon inducers ( polyguacyl and double-stranded RNA) in combination with original H1N1 and H3N2 influenza viruses and recombinant strains with the same antigenic properties in laboratory animals are presented. Recombinants were found to produce a more marked effect: 3--6-fold increased protection of mice depending on the interferon inducer, higher titres of interferon and antibody, than the original influenza viruses. A simultaneous use of interferon inducers and recombinant influenza virus strains may be recommended for influenza prevention.