title: Clonal nature of the immune response to phosphocholine. VI. Molecular uniformity of a single idiotype among BALB/c mice.
abstract: The molecular heterogeneity of IgG antibodies to phosphocholine (PC) having a defined idiotype was examined in BALB/c mice immunized with PC-keyhole limpet hemocyanin (KLH). Specific antibodies were separated by isoelectric focusing in polyacrylamide gels and characterized for PC-binding, idiotype, and isotype by direct in situ labeling with 125I-labeled reagents followed by autoradiography. After immunization with PC-KLH, BALB/c produce 20 to 100 microgram/ml of IgM and 80 to 300 microgram/ml of IgG anti-PC antibody. The dominant fraction of anti-PC antibodies in BALB/c (and a lesser fraction in other strains) possesses idiotypic determinants found on a PC-binding myeloma, TEPC-15. Among 65 BALB/c examined, all produced an identical spectrotypic pattern of antibodies possessing T15 idiotypic determinants. Three major sets of T15-idiotype bearing bands were observed, but they belonged to three different IgG subclasses: IgG1, IgG2, and IgG3. These data support the germ line origin for this dominant set of antibodies in the anti-PC repertoire of BALB/c and indicate that they arise from a single rather than multiple VH-VL pairs.
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D002794:Choline / Q000031:analogs & derivatives*; D002999:Clone Cells / Q000276:immunology; D007074:Immunoglobulin G; D007130:Immunoglobulin Idiotypes / Q000096:biosynthesis*; D007525:Isoelectric Focusing; D051379:Mice; D008807:Mice, Inbred BALB C; D009194:Myeloma Proteins / Q000276:immunology; D010767:Phosphorylcholine / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G; D007130:Immunoglobulin Idiotypes; D009194:Myeloma Proteins; D010767:Phosphorylcholine; D002794:Choline