Idiotypic analysis of anti-GAT antibodies. VIII. Comparison of interstrain and allotype-associated idiotypic specificities.

A guinea pig anti-idiotypic antiserum made against pooled specifically purified A/J anti-GAT antibodies was characterized. This antiserum contains anti-idiotypic antibodies specific to interspecies, interstrain, and allotype-linked idiotypic determinants. These idiotypic determinants are associated with the combining sites of idiotypic antibodies that are induced by GT-related but not GA-related antigenic moieties. Genetic and strain distribution studies indicated that the shared allotype-linked idiotypic determinants are controlled by Igh-1e- or Igh-1b-linked genes. The interrelationships of the allotype-linked and interstrain CGAT idiotypic specificities are described using monoclonal anti-GAT hybridoma antibodies. Four of 7 hybridoma anti-GAT antibodies of C57BL/6 origin expressed a major fraction of the idiotypic specificities of A/J anti-GAT antibodies. These 4 hybridoma antibodies also carried the common interstrain idiotype, termed CGAT, but not all CGAT-bearing anti-GAT hybridoma antibodies expressed the allotype-linked idiotypic specificities. The Ig-1b-positive, F17-167.1 hybridoma anti-GAT antibody was used as a ligand to selectively identify the major allotype-linked idiotypic specificities, which were designated Gte idiotype.