IMMUNOLOGICAL AND TROPHICAL EFFECTS OF SACCHAROMYCES-BOULARDII ON THESMALL-INTESTINE IN HEALTHY-HUMAN VOLUNTEERS

Saccharomyces boulardii (S.b.) is used for the prevention and treatmen t of diarrhea of different etiologies. We prospectively investigated t he effects of S.b. on lymphocytes and duodenal mucosa. Before and afte r oral administration of S.b. for 3 weeks, circulating and intestinal lymphocytes were isolated and characterized by flow cytometry. Trophic effects on duodenal mucosa were investigated by morphometry and deter mination of brush border enzyme activity. Results were compared intrai ndividually before and after S.b. In intestinal lymphocytes no phenoty pic changes were observed. CD4+ cells of the peripheral blood had a si gnificantly increased expression of CD25 (p < 0.02). None of twelve vo lunteers had an increase in villous surface area (n.s.). Immunoglobuli n A content in small intestine secretion was unaltered. An increase in brush border enzyme activity of lactase, alpha-glucosidase, and alkal ine phosphatase was observed (p < 0.01). Our findings indicate that S. b. has a positive effect on the maturation of enterocytes and only a m inor influence on lymphocytes.