Abstract: The ability of adherent and nonadherent peripheral blood mononuclear cells (PBMC) from forty patients with schistosomiasis to produce IL-1 and IL-2 was studied. The results indicated that ConA-stimulated nonadherent-PBMC from patients exhibited a decreasing ability to produce IL-2 compared with controls (P0.001), and that their ConA-activated blast cells expressed a smaller number of cell surface IL-2 receptor since IL-2 adsorption to the patient cells was lower than that to the normal cells (P0.01). On the other hand, IL-1 production by LpS-stimulated adherent-PBMC from the patients was in agreement with that from the normal controls (P0.05). From above results, it seems that human organism following infection of Schistosoma japonicum might display a sort of supressive phenomenon n the production of and the response to IL-2.