Resistance to Schistosoma mansoni by transplantation of APO Biomphalaria tenagophila.

Transplantation of the haematopoietic organ from Biomphalaria tenagophila (Taim strain, RS, Brazil), resistant to Schistosoma mansoni, to a highly susceptible strain (Cabo Frio, RJ, Brazil) of the same species, showed in the recipient snails resistance against the trematode, when a successful transplant occurred. The success of transplantation could be confirmed by a typical molecular marker of the Taim strain in haemocytes of the recipients (350 bp detected by PCR-RFLP). The recipient snails which did not present the donor marker in haemocytes (unsuccessful transplantation) were infected with the parasite. The use of an atoxic modelling clay for closing the hole in the transplantation site reduced significantly the mortality caused by bleeding after transplantation procedures.