The nature and functions of specific immune response genes and their products.

Antibodies produced by inbred mouse strains immunized with the random synthetic polypeptide poly (Tyr,Glu)-poly(DLAla)--polyLys denoted (T,G)-A--L were found to be specific mainly to the ordered peptide Tyr-Tyr-Glu-Glu. Low responder H-2k mice, upon immunization with either the random (T,G)-A--L or the ordered (T-T-G-G)-A--L coupled to methylated bovine serum albumin (MBSA), produce antibodies with comparable titers to those observed in high responder H-2b mice following immunization with the antigens alone or with their complexes with MBSA. A comparison of the above antibodies have led to the conclusion that low responder mice, upon immunization with the synthetic antigens complexed with MBSA, produce antibodies of the same specificity and quality as those of high responders (as shown by the isoelectric focusing technique) and they also have the same affinity and heterogeneity as antibodies of H-2b mice (measured by equilibrium dialysis and antigen binding capacity assay). Anti-idiotypic sera to anti-T,G)-A--L antibodies of C3H.SW (H-2b,Ig-1a) mice were raised in guinea pigs. C3H.SW anti-(T,G)-A--L antibodies from different pools cross reacted idiotypically. Anti-(T,G)-A--L antibodies of CWB (H-2b, Ig-1b) mice did not react with the anti-idiotypic serum suggesting linkage between the genes coding for idiotypes and allotypes. C3H/DiSn (H-2k, Ig-1a) anti-(T,G)-A--L antibodies elicited by immunization with (T,G)-A--L complexed to MBSA reacted with the anti-idiotypic serum to the same degree as C3H.SW anti-(T,G)-A--L antibodies, confirming the similarity between the high and low responder anti-(T,G)-A--L antibodies. C3H.SW (H-2b) mice as well as C3H/DiSn (H-2k) mice were found to be capable of producing an antigen specific factor from "educated" T cells which replaces the helper effect of T cells in the process of antibody production. On the other hand B cells of H-2k mice were not triggered by a factor of either high or low responder specific T cells. The activity of a C3H.SW (T,G)-A--L specific T cell factor was removed after passage on a Sepharose column coupled to the anti-idiotypic serum prepared against C3H.SW anti-(T,G)-A--L antibodies, suggesting similarity between the antigen specific T cell factor and the B cell recognition system. A (T,G)-A--L specific factor produced by C3H/DiSn (H-2k, Ig-1a) "educated" T cells reacted with the anti-idiotypic serum as well. Thus, C3H.SW high and C3H/DiSn low responder (T,G)-A--L specific T cell factors cross react at the level of their binding site for antigen.