ArticleTerzin AL, Djurisić S, Vujkov V.
Acta Virol. 1979 Mar;23(2):120-7.
In native, heated or otherwise treated egg white and in sera of men and guinea pigs, haemagglutination inhibition titres were determined against three inhibitor-sensitive (IS) strains and one inhibitor-resistant (IR) variant on influenza A virus. A few human sera with no detectable antibody revealed high inhibition titres even against the IR variant. Human sera after treatment with trypsin and periodate revealed mostly a reduction or no change, and exceptionally an increase of their inhibition titre. The extent of these changes varied with different influenza virus strains and showed a positive correlation with the inhibitor content and no correlation with the antibody levels of the sera. The so-called "nonspecific" thermostable inhibitors possess a certain degree of specificity for different influenza virus strains.