CELL-MEDIATED-IMMUNITY TO SCHISTOSOMES - EVALUATION OF MECHANISMS OPERATING AGAINST LUNG-STAGE PARASITES WHICH MIGHT BE EXPLOITED IN A VACCINE

This report describes parallel studies examining T cell and cytokine r esponses to Schistosoma mansoni in mice and man, The prevalence of IFN g production amongst murine (C57BL/6) T cell lines and clones, plus go od DTH reactivity by IFNg-secreting clones, highlights the predominanc e of the Th1 response in the pulmonary immunity characteristic of the murine irradiated vaccine model, In human studies, effects of anti cyt okine antibodies on the proliferation of PBMC from human patients to v arious soluble schistosome antigen preparations have been examined. Da ta suggest that both Th1 (against early antigens) and Th2 (against lat e antigens) responses are present. A role for IL-10 is highlighted in chronic intestinal, but not acute or chronic hepatosplenic patients, a s a downregulator of responses which are associated with morbidity and are against late stage antigens.