title: Assignment of antigenic determinants to separated I-A kappa chains.
abstract: The alpha- and beta-chains of the I-A kappa antigen from the AKTB-1b B cell lymphoma were separated by ion-exchange chromatography on CM-Sephadex in the presence of propionic acid and urea. Removal of the denaturants by dialysis produced isolated chains that regained a significant amount of their native configuration. These materials were used with a battery of monoclonal antibodies in a direct binding assay to localize specific alloantigenic determinants to the A alpha kappa or A beta kappa chains. This method allowed the assignment of the nominal specificity Ia. 17 and at least one epitope of the specificity Ia.2 to the A beta kappa chain. Finally, the I-A kappa antigen from the B cell lymphoma AKTB-1b was shown to be identical, by the criterion of tryptic peptide analysis, to that derived from normal B10.BR splenocytes. This constitutes the first demonstration that the polypeptide portion of a tumor-derived class II MHC antigen is identical to that derived from a normal tissue.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D001666:Binding Sites, Antibody; D002852:Chromatography, Ion Exchange; D000939:Epitopes; D005802:Genes, MHC Class II; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D051379:Mice; D008806:Mice, Inbred AKR; D008810:Mice, Inbred C57BL; D011487:Protein Conformation; D013154:Spleen / Q000166:cytology / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D000949:Histocompatibility Antigens Class II