title: Analysis of the repertoire of anti-idiotypic B-cell responses to self-I-Ak- or -I-Ek-reactive monoclonal antibodies in A.TL mice.
abstract: Twenty anti-idiotypic antisera (anti-Ids) were produced in A.TL mice to self-I-Ak or -I-Ek-reactive monoclonal antibodies (mAbs), constructed in the A.TH anti-A.TL combination. The reactivity of these anti-Ids was examined in a panel of 31 anti-Iak A.TH mAbs, using direct idiotype binding, cross-competitive inhibition of idiotype binding, and isoelectrofocusing (IEF) assays. Among 13 anti-Ids produced against anti-I-Ak mAbs, one only recognized individual idiotypic specificities (IdIs) on its corresponding mAb, while the 12 others identified homologous IdIs and recurrent idiotypic specificities also expressed on heterologous anti-I-Ak and/or I-Ek mAbs. Two sets of major cross-reactive idiotypes (IdXs) were characterized on two groups of mAbs recognizing public Ia.1, I-Ak,f,u and r) or private (Ia.2, I-Ak) determinants clustered in two spatially distinct epitope regions of the I-Ak molecule, respectively. By contrast, most (5/7) of the anti-Ids raised against mAbs recognizing polymorphic or monomorphic (Ia.7-like) I-Ek determinants displayed specificity apparently restricted to their corresponding mAb IdIs. This finding contrasted with the previous characterization, using xenogeneic anti-idiotypic reagents, of an interstrain IdX expressed on all mAbs defining Ia.7-like determinants in the IEk epitope group I. These data indicate that A.TL mice can readily develop anti-idiotypic responses towards self Ia-reactive mAb minor idiotypes (IdIs) and that recognition of anti-Iak mAb IdXs in such mice is preferentially observed when anti-I-Ak mAbs are used as immunogens.
mesh_terms: D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000032:analysis; D000911:Antibodies, Monoclonal / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D001666:Binding Sites, Antibody; D003429:Cross Reactions; D005260:Female; D007130:Immunoglobulin Idiotypes / Q000276:immunology; D007457:Iodine Radioisotopes; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D007130:Immunoglobulin Idiotypes; D007457:Iodine Radioisotopes