Role of IgG Antibodies from Irradiated Cercaria-Immunized Rabbits in the PassiveTransfer of Immunity to Schistosoma Mansoni-Infected Mice

摘要

Antibodies of the IgG subclass isolated from the sera of rabbits immunized withcercariae subjected to 50 Kilorads of gamma irradiation passively provided partial immunity against Schistosoma mansoni challenge in C57Bl/6J mice. These mice exhibited reductions in adult worm burdens of 43-61% compared with recipients of normal rabbit antibodies. Passively transferred IgG antibodies were most effective when given 4-7-days postchallenge; they were less effective when given just before challenge, and were totally ineffective when given 15 days postchallenge. It was also shown that the Fc portion of the IgG molecule was important for passive transfer of immunity. Finally, we observed that although some antibodies from irradiated cercaria-immunized rabbits recognized keyhole limpet hemocyanin (KLH), these KLH cross-reacting antibodies were not necessary for successful passive transfer of immunity. Antibodies from a KLH-immunized rabbit also failed to passively protect mice.... IgG antibodies, Schistosoma mansoni, Irradiated cercaria, Immunity passive transfer, Mice.