[Use of a multivariate analysis method for determining the interconnection of genetic markers with gene clusters and solution of taxonomy problems for the recombinant influenza A virus model].

The collection of influenza A viral recombinants has been studied for determining interconnection of the definite genetical marker (pneumovirulence for mice) with genes constellation by the technique of image identification. Pneumovirulence is found to be defined by correlation of polymerase complex M-, NS- and NA-genes. The data on NA influence on pneumovirulence were obtained for the first time, the phenomenon being found only with the use of image identification technique.

[Isolation and comparative study of highly reproductive recombinant influenza A viruses with a high antibody sensitivity].

The possibility of generating avid and highly reproductive recombinants of influenza A virus (H3N2, H3N1) using strain A/PR/8/34 (H1N1) as a donor of high reproductive activity was demonstrated. In the process of recombination, the transmission of the gene responsible for synthesis of avid hemagglutinin H3 from one virus variant to another provides for high avidity of recombinants. However, a possible influence of other influenza A virus genes on the manifestation of avidity cannot be ruled out.

[The heterogeneity of an influenza virus A population in its capacity to induce the synthesis of avid antibodies].

Influenza A virus variants were found to be capable of inducing synthesis of avid antibodies when different species and lines of animals were immunized. CBA mice were the most convenient model permitting differentiation of "avidogenic" from "nonavidogenic" virus variants with a high degree of certainty. Recombinants may differ from parental viruses in their capacity to induce synthesis of avid antibody; with this, the transmission of only one gene (HA) from the "avidogenic" parent into the system of genes of A/PR/8/34 st in ensured a high "avidogenicity" of the recombinant.

[Study of influenza virus hemagglutinin H3 avidity using monoclonal antibodies].

The results of a comparative study of the features of antigenic determinants of avid and non-avid variants of influenza virus hemagglutinin H3 and of the influence of the mode of antigen presentation on the degree of its avidity are presented. The avidity of influenza virus hemagglutinin was shown to be determined by the capacity of individual antigenic determinants to interaction with antibodies. The antigenic determinants of avid hemagglutinin possessing a high functional activity in interaction with antibodies may have the spatial configuration which does not change in different modes of the antigen presentation.

[Structural characteristics of a population of antigenic variants of the influenza A(H3N2) virus].

The data have been obtained indicating that clone distribution by the antigen avidity in the population of influenza A (H3N2) virus corresponds to normal distribution. The degree of avidity of individual strains is determined by the predominant content of clones with high or low avidity. Virus purification by ultracentrifugation in sucrose density gradient results in increasing the avidity of the preparation as compared with the original allantoic cultures.