title: Characterization of idiotopes on MOPC 315 IgA using monoclonal antiidiotypic antibodies.
abstract: The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA) D10 (IgG2a), A2(IgG1), G3 (IgG2b) and F1 (IgG2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA, reassociated H315 L315 and FV31¿5 but not with free H315, L315, VH315 or VL315. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H315 and L315. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an amino acid sequence on H315 which requires an interaction with either L315 or L460 for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted.
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology*; D004136:Dinitrobenzenes / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D005260:Female; D006241:Haptens / Q000276:immunology; D007070:Immunoglobulin A / Q000276:immunology*; D007128:Immunoglobulin Fragments / Q000276:immunology; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009194:Myeloma Proteins / Q000276:immunology*
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D004136:Dinitrobenzenes; D000939:Epitopes; D006241:Haptens; D007070:Immunoglobulin A; D007128:Immunoglobulin Fragments; D007130:Immunoglobulin Idiotypes; D009194:Myeloma Proteins