Abstract: | The results of this study provide evidence that protein A may render IgG immunogenic in the autologous host. Antibodies to human but not rabbit IgG were detected in sera of rabbits immunized with a mixture of autologous serum and protein A. Anti-human IgG antibodies appeared within 2 weeks at which time the antibodies were of the IgM class. Upon further immunization, both IgM and IgG antibodies were produced with the IgG class predominating. The antibodies elicited by a mixture of protein A with autologous IgG resembled those which arise in response to autologous IgG that has been denatured by physicochemical means, in that they react mainly with foreign species IgG and weakly, if at all, with IgG of rabbit origin. |