IgA isotype-restricted idiotypes associated with T15 Id+ PC antibodies.
Idiotypes are believed to be due to the structural conformation of the variable region of immunoglobulins (Ig). We have found an idiotype (C3-24) that requires both variable and constant regions of the heavy chain to be expressed. C3-24 Id is associated with both the T15 variable region from anti-phosphorylcholine (PC) antibodies and the constant region for the alpha-heavy chain. High titer anti-PC serum from a variety of inbred strains of different Ig haplotypes failed to express C3-24 Id. However, when IgA but not IgG or IgM fractions were isolated from a pool of anti-PC serum from BALB/c mice, more than 70% of the molecules expressed C3-24 Id. The high frequency of the expression of C3-24 Id in IgA anti-PC hybridoma proteins from mice of different Ig haplotypes and in the IgA fraction of normal anti-PC antibodies from BALB/c and presumably other strains of mice suggests that idiotypic determinants produced by the three-dimensional product of VH and CH regions may not be unusual.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis / Q000145:classification*; D000918:Antibody Specificity; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D002794:Choline / Q000031:analogs & derivatives*; D007070:Immunoglobulin A / Q000235:genetics / Q000378:metabolism*; D007126:Immunoglobulin Allotypes / Q000235:genetics / Q000378:metabolism*; D007127:Immunoglobulin Constant Regions / Q000235:genetics / Q000378:metabolism; D007143:Immunoglobulin Heavy Chains / Q000235:genetics / Q000378:metabolism; D007130:Immunoglobulin Idiotypes / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D010767:Phosphorylcholine / Q000276:immunology* / Q000378:metabolism
D000911:Antibodies, Monoclonal; D007070:Immunoglobulin A; D007126:Immunoglobulin Allotypes; D007127:Immunoglobulin Constant Regions; D007143:Immunoglobulin Heavy Chains; D007130:Immunoglobulin Idiotypes; D010767:Phosphorylcholine; D002794:Choline