Naturally induced auto-anit-idiotypic antibodies. Induction by identical idiotopes in some members of an outbred rabbit family.

Abstract

Naturally induced auto-anti-idiotypic (AAI) antibody responses specific for antimicrococcal antibody idiotypes were detected in 42% of the rabbits in a family immunized with Micrococcus lysodeikticus. The natural AAI response of each rabbit recognized only a portion (11-41%) of that individual's total antimicrococcal antibody population. Cross-reactions of idiotypes were observed within the group of rabbits exhibiting natural AAI responses. Examination of the basis for the cross-reactions showed that the natural AAI antisera recognized identical idiotopes on the antimicrococcal F(ab')2 fragments from each rabbit that made an AAI response. The cross-reactive idiotopes were shown to be of paternal origin and were found in the antimicrococcal antibodies of each offspring. The data strongly support the idiotypic network concept that naturally induced AAI responses may occur routinely in outbred normal individuals as a result of antigenic stimulation. Further, the data suggest that the induction of regulatory AAI antibody responses in outbred rabbits may depend on the expression of particular germ line idiotopes.

Regulation of natural antiallotype antibody responses by idiotype network-induced auto-antiidiotypic antibodies.

“…The data showed that the natural auto-antiidiotypic antibodies directed against first wave anti-al antibodies from rabbit 360 reacted equally well with first wave anti-al antibodies from rabbits 360 and 365 and the same was true for the reaction of the anti-al antibodies of rabbit 365. These present data concerning cross-reactivity of the idiotopes recognized with natural auto-antiidiotypic antibodies in the anti-al responses confirm and extend the similar observation on the crossreactive idiotypes detected in antimicrococcal responses made earlier in one of our laboratories (35). Thus, data are now available for two unrelated antigen systems in which natural auto-antiidiotypic antisera are strongly cross-reactive with idiotopes on antibodies of the same specificity from outbred individuals.…”

“…These idiotopes in (35) were found only in sera of rabbits which mounted auto-antiidiotypic responses. Both the antimicrococcal idiotopes (35) and the anti-a1 idiotopes described here were highly sensitive to low concentrations of reducing agent which suggests that these idiotopes may be a special subset in rabbits that is highly reduction-sensitive.…”

“…We were only successful when we used a method for labeling the anti-al F(ab')2 fragments that did not employ reducing agents in the protocol. In a previous paper the extreme sensitivity of antimicrococcal idiotopes to reducing agents was documented when natural auto-antiidiotypic antiserum was used (35). The reduction properties of the idiotopes is described fully in another paper (36).…”