Clonal nature of the immune response to phosphorylcholine. IV. Idiotypic uniformity of binding site-associated antigenic determinants among mouse antiphosphorylcholine antibodies.

A new idiotypic determinant(s) on mouse anti-PC antibodies is described. Antibodies to the determinant(s) were raised in rabbits by immunization with HOPC 8, a PC-binding myeloma protein, and were isolated from HOPC 8 immunoadsorbent by elution with PC. These antibodies react with binding site determinants on anti-PC antibodies raised in all 15 inbred mouse strains tested regardless of histocompatibility or allotype, but fail to react with antibodies of other specificities or with anti-PC antibodies raised in other rodent species. These results correlate closely with other studies which show similar binding specificity of anti-PC antibodies raised in 17 different strains of mice. The site-associated idiotypic determinant(s) is clearly distinct from that detected by mouse anti-HOPC 8 antisera. This latter determinant(s) is present on anti-PC antibodies of only a few strains of mice and may not be in the binding site.