Mapping the idiotopes of a monoclonal anti-myoglobin antibody with syngeneic monoclonal anti-idiotypic antibodies: detection of a common idiotope.
A panel of syngeneic monoclonal anti-idiotypic antibodies was prepared by immunizing A.SW mice with keyhole limpet hemocyanin-coupled A.SW monoclonal anti-myoglobin (HAL 19, IgG1) and screening the cloned hybridomas for production of IgG2 binding to idiotype but not to certain other anti-myoglobin antibodies of the same subclass in an ELISA. With these antibodies, we identified three nonoverlapping idiotopes, based on three clusters of monoclonal anti-idiotopes that mutually inhibit within each cluster, but not between clusters (Cluster I: S2, S6, S8; Cluster II: S5, S7; Cluster III: S9). Only Cluster II antibodies block the binding of myoglobin to HAL 19 and so identify a binding site-related idiotope(s). Binding of both Cluster II monoclonals (S5 and S7) to Hal 19 is inhibited by a rabbit anti-idiotype that we previously reported detects a common cross-reactive anti-myoglobin idiotope in immune sera. However, only one of these, S7, and not S5, identifies an idiotope that is present on 20 to 30% of A.SW anti-myoglobin antibodies in immune sera and ascites. The panel of syngeneic monoclonal anti-idiotype antibodies also detects new idiotopes not detected by the rabbit anti-idiotype. The development of a panel of syngeneic monoclonal anti-idiotypic antibodies to different clusters of idiotopes on the same antibody molecule, including one that identifies a major common idiotope in immune sera, should allow the analysis of possible idiotype network regulation in vivo and in vitro in a completely syngeneic system.
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000032:analysis* / Q000096:biosynthesis; D000911:Antibodies, Monoclonal / Q000032:analysis* / Q000096:biosynthesis; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D003429:Cross Reactions; D007106:Immune Sera / Q000032:analysis; D007130:Immunoglobulin Idiotypes / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D051379:Mice; D008815:Mice, Inbred Strains; D009211:Myoglobin / Q000276:immunology* / Q000378:metabolism; D011817:Rabbits; D014907:Whales
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D007106:Immune Sera; D007130:Immunoglobulin Idiotypes; D009211:Myoglobin