Altered Immunogenicity Produced by Change in Mode of Linkage of Hapten to Carrier

Summary

The immunogenicity of three different conjugates with DNP as hapten and BSA as carrier were compared. Guinea pigs immunized with DNP coupled to amino groups or carboxyl groups responded with high anti-DNP and low anti-BSA antibody production, while those immunized with DNP on tyrosyl residues gave the reverse response. DNP coupled to amino and carboxyl groups produced much more drastic effects on native BSA determinants as measured by precipitin test and delayed sensitivity reactions. It is suggested that haptens coupled to these groups are on the exterior surface of the protein where they are more likely to contact receptors of immunocompetent cells and more likely to alter surface configurations of the native molecule.

This investigation was supported by a grant from the U.S. National Institutes of Health.