[Functional activity of glycoproteins from interepidemic isolates of the influenza virus].

The results of the study into the function of glycoproteins of influenza viruses isolated in the 1987 interepidemic period. Natural isolates were found to have virus particles with deficient neuraminidase activity but retained hemolytic and infectious activity. Biological sequences of the lack of neuraminidase activity in the isolates consisted in disorders of sialic acid metabolism in the infected cells, blocking of the receptor site of hemagglutinin and increased sensitivity to inhibitors. It is assumed that the interepidemic virus isolates represent a biologically heterogeneous population in which particles with deficient neuraminidase activity are prevalent.