Genetics of the alpha 1,6-dextran response: expression of the QUPC52 idiotype in different inbred and congenic strains of mice

Antibodies to dextran B512 were raised in various strains of mice and were assayed by a radioimmunoassay procedure. Idiotypic antibodies to the IgA(k) dextran B512 binding myeloma proteins QUPC52 and W3129 of BALB/c origin were prepared in rabbits. After adsorption each antiserum was specific for the immunizing myeloma protein and did not react with hundreds of other myeloma proteins; nonetheless, antibodies to dextran B512 from various strains of mice cross-reacted in these test systems. Of the 2 idiotypes tested, the W3129 idiotype was more universally expressed in different strains of mice. The QUPC52 idiotype was the predominant idiotype in BALB/c anti-dextran B512 antibodies and was found in only a few other inbred strains. Using a battery of congenic and inbred strains, it was shown that the QUPC52 idiotype was controlled by genes linked to the Igh complex locus (chromosome 12) and to the Ig kappa complex locus (chromosome 6). The W3129 idiotype was found in a number of stocks of mice in the genus Mus recently isolated from the wild. The QUPC52 idiotype thus far was found only in inbred mice.