Immunosuppression and parasitic diseases: experimental Schistosomiasis mansoni.

Cyclosporin A is an immunosuppressive agent of clinical relevance and also possesses a potent antiparasitic effect. In organ transplants and tissue grafts, this agent is frequently used in combination with hydrocortisone. Thus the reciprocal effects of these immunosuppressants on experimental Schistosomiasis mansoni were studied. Mice were subcutaneously inoculated with Schistosoma mansoni cercariae, and infected animals which were treated or not with oxaminiquine were subsequently immunosuppressed or not. Potentially fatal exacerbations of parasitemia and parasitism were observed in immunosuppressed animals, in contrast to control animals, suggesting that in transplanted patients an adverse Schistosomiasis may be evolved. Despite the prominent immunomodulation effect, these drugs showed a moderate antiparasitic effect, complementing the schistosomicidal activity of oxamniquine. This effect also seems favorable in the antischistosomal treatment of transplanted patients with S. mansoni infection.