Autoanti-allotype antibodies and idiotypic network regulating allotype production in rabbits.

Anti-idiotype sera were prepared by immunization of inbred B/J as well as random-bred rabbits with anti-b4 antibodies from a syngeneic rabbit. These antisera inhibited the binding between b4 and anti-b4 from different animals to various degrees. Anti-anti-idiotype sera prepared in syngeneic rabbits also inhibited the binding between anti-b4 and anti-idiotype from different animals, and did not contain anti-b4 antibodies. These results suggest that at least some anti-b4 and anti-idiotype antibodies could carry the same or similar idiotypes, respectively. Treatment of b4b5 F1(B/J X Chbb:HM) hybrids at birth with these anti-idiotype sera from B/J rabbits resulted in a modulated production of the allelic allotypes in the serum. Anti-idiotype serum against anti-b4 induced an elevated production of b4 with little effect on the production of b5 in the same serum. In F1 hybrids born from a doe immunized with anti-idiotype antibodies against anti-b4, there was a decreased production of b4, followed by a gradual recovery to normal levels. Serum b5 levels in F1 offspring of one particular Chbb:HM doe were extremely low, as compared with those in other F1 hybrids and the b4/b5 ratio in the serum was unusually high. Such low b5 levels were no longer observed when offspring of this doe were given normal b5 serum at birth. Anti-b5 activity was not detected in the serum of this doe. These observations strongly suggest the presence in normal rabbits of the autoanti-allotype antibody and of the idiotypic network involving this antibody and regulating allotype production.