Antibodies are involved in the protective immunity induced in mice by Schistosoma mansoni schistosomula tegument (Smteg) immunization

The Schistosoma mansoni schistosomula tegument (Smteg) plays an important role in triggering the host immune response and mice immunization with Smteg formulated with Freund's adjuvant or alum+CpG induce partial protection against S.mansoni infection associated with an increased antibody production. In this study, we investigated the role of these antibodies in parasite killing both in vitro and in vivo. We demonstrated that these antibodies were able to bind to the surface of S.mansoni recently transformed schistosomula and that these antibodies significantly increase the percentage of schistosomula killed in vitro by complement activation. Passive transference of immune sera decreased the parasite burden and the number of eggs trapped in the organs of mice that received sera containing anti-Smteg antibodies. These results demonstrate that antibodies specific to surface tegumental antigens are involved in parasite elimination in mice immunized with Smteg.