Relationship between biological activities of polymers. I. Immunogenicity, C3 activation, mitogenicity for B cells and adjuvant properties.

The effect of thirteen compounds on C3 activation, mitogenicity for B lymphocytes and on the immune response was tested. Only two of the compounds tested, polyinosinic acid and a high molecular weight polyethylenesulphate induced C3 conversion, while eleven out of the thirteen compounds (negative charged immunogenic or non-immunogenic polymers including the three C3 active compounds) stimulated thymidine incorporation in B lymphocytes. The non-charged (T-independent) immunogens dextran and polyvinylpyrrolidone neither activated C3 nor BP lymphocytes. With the exception of single-stranded polyribonucleic acids, the compounds stimulating DNA synthetis in B cells enhanced the response of the mice to a suboptimal dose of sheep red blood cells. In conclusion C3 activation, intrinsic (T-independent) immunogenicity and B-cell stimulation are not correlated properties. However, B-cell mitogenicity and adjuvanticity seem to be related.