Maternal transfer of resistance to Schistosoma mansoni.

Infected mother rats, resistant to Schistosoma mansoni, yielded offspring that were significantly resistant to a primary infection with cercariae, demonstrating the maternal transfer of protection. Newborns of normal mother rats could also be made resistant by the injection of protective immune rat serum, indicating that the effector phase components required for expression of protective activity are present in the newborn rat. The injection of the protective antiserum into newborns of the infected mothers enhanced resistance to a level exceeding 90%.