Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Marvin L. Hackert. Vita. Includes bibliographical references.

The use of probiotics has emerged in the last decades as a promising strategy when it comes to the treatment of inflammatory diseases. Through modulation of composition of the intestinal microbiota and the signalling it provides, probiotics can favourably tune the immune system. Beneficial effects of probiotic treatment have been documented in multiple animal inflammatory disease models. The effect of probiotic treatment on uveitis-a sight- threatening disease-has however not yet been described. In our study, we have tested two commercially available probiotics-Escherichia coli Nissle 1917 (EcN) and Escherichia coli O83:K24:H31 (EcO)-in the treatment of experimental autoimmune uveitis (EAU). The disease severity was assessed by ophthalmoscopy and histology, proportions of leukocyte populations and intracellular expression of cytokines were evaluated by flow cytometry and the gut immune environment was analysed by tissue culture and ELISA. We found that prophylactic and early oral treatment with EcN reduces the severity of EAU. However, EcO treatment does not. The effects were accompanied by immune changes including a lowered production of inflammatory cytokines in Peyer's patches, a shift in macrophage populations in ileum and mesenteric lymph nodes or a reduced IRBP-specific response of CD4+ T...