title: Reconstitution of genetically regulated responses against random and ordered synthetic polypeptides by methylated bovine serum albumin as analyzed by isoelectric focusing.
abstract: In previous publications it was shown by avidity measurements, cross-reactivity patterns and genetic analyses, that the tetrapeptide T-T-G-G is the immuno-dominant epitope of the synthetic polypeptide (T, G)-A--L. In the present study this close immunological relationship between the random multichain copolymer (T, G)-A--L and the ordered analogue (T-T-G-G)-A--L is extended by two additional criteria. First, the immune response against (T-T-G-G)-A--L in H-2k nonresponder mouse strains can be reconstituted to high antibody levels by complexing this antigen to methylated bovine serum albumin, as was tested earlier for (T,G)-A--L. The antibodies elicited upon reconstitution in both antigenic systems are directed mainly against the same determinant, T-T-G-G. Second, isoelectric focusing analysis of specific antisera developed with radiolabeled antigen revealed restricted 7 S IgG antibody populations in high responder and reconstituted high and low responder mice. The spectra were found to be of similar complexity in the (T,G)-A--L and in the (T-T-G-G)-A--L system. From these data it was concluded that the repertoires of specific B cells to T-T-G-G are very similar in high and low responder strains, and the defect in the H-2k low responder systems should be located at the level of T-B cell cooperation.
mesh_terms: D000409:Alanine; D000818:Animals; D000917:Antibody Formation; D000937:Antigen-Antibody Reactions; D005973:Glutamine; D007525:Isoelectric Focusing; D008239:Lysine; D051379:Mice; D008815:Mice, Inbred Strains; D010455:Peptides / Q000276:immunology*; D012710:Serum Albumin, Bovine / Q000276:immunology; D014443:Tyrosine
chemical_list: D010455:Peptides; D005973:Glutamine; D012710:Serum Albumin, Bovine; D014443:Tyrosine; D008239:Lysine; D000409:Alanine