ABSTRACT
Hapten systems are ideal for approaching the question of a germline-encoded network, because unlike the responses to many protein antigens, the primary responses to haptens are homogeneous. Perhaps the most interesting aspect of the D segments of these molecules is the presence of sequences which appear to mimic the structure of the original antigen — the random terpolymer glu-ala-tyr (GAT). The Ab2s studied in the nitrophenyl acetyl and GAT systems are all syngeneic; both syngeneic and allogeneic Ab2s have been studied in the arsonate system. Weak syngeneic anti-idiotypes (ID) responses could be due to some type of suppression. Syngeneic monoclonal anti-Id antibodies were derived from mice immunized with either monoclonal or polyclonal BALB/c anti-GAT antibodies expressing the public cGAT Id. Jerne extended his ideas in 1982 by grouping Ab2s into two functional subsets: those that recognize determinants present in the V region, and those that represent internal images of the original antigen.
