CYTOKINE REGULATION OF HUMAN IMMUNE-RESPONSE TO SCHISTOSOMA-MANSONI -ANALYSIS OF THE ROLE OF IL-4, IL-5 AND IL-10 ON PERIPHERAL-BLOOD MONONUCLEAR CELL RESPONSES

The role of cytokines on the in vitro proliferative response of periph eral blood mononuclear cells (PBMC) from Schistosoma mansoni infected patients to soluble egg (SEA) and adult worm antigens (SWAP) were eval uated. The results obtained demonstrated that the proliferative respon se of PBMC from chronic intestinal (INT) patients to SEA and SWAP is i ncreased by the blockage of IL-10 with specific monoclonal antibodies (MAb). The effects of these antibodies were readily reversed by the ad dition of recombinant IL-10. In contrast, no effect was observed on th e PBMC response of acute and hepatosplenic patients (HS) in the presen ce of anti-IL-10. Anti-IL-4 antibodies decreased the PBMC response of the intestinal (INT) and HS individuals to SEA and SWAP, and the PBMC response of acute patients to SEA but not to SWAP. Addition of anti-IL -5 MAb did not decrease the PBMC response of acute patients to SEA or SWAP. These results suggested that IL-10 has an important role in the modulation of the immune response in chronic asymptomatic patients and that this cytokine may be an important factor in controlling morbidit y.