The immune response of carp against dextran. An analysis of the idiotype heterogeneity.

The expression of a "species-specific" idiotype with specificity for alpha(1-6) dextran in carp is described. All tested carp anti-dextran antisera react with a rabbit anti-Id (carp anti-dex) serum. The rabbit anti-Id serum can be partially inhibited by the specific ligand, dextran T70 or isomaltodecaose but not or only weak with other, unrelated carbohydrates. These data confirm our statement, that a limited germline V-gene repertoire may code for antibodies in fish.