Cyclosporin A: alterations of the cellular immune response in S-antigen-induced experimental autoimmune uveitis.

We have previously shown that Cyclosporin A (CsA) is effective in preventing S-antigen (S-Ag)-induced experimental autoimmune uveitis (EAU). Lewis rats, which readily develop EAU, were studied for the alterations in cell-mediated immune functions associated with CsA therapy. Lymph nodes draining the site of S-Ag immunization were significantly smaller in the CsA-treated animals when compared to the nonprotected group (p less than 0.01), and also showed profound histologic alterations when compared to controls. In vitro responses of lymphocytes from lymph node and peripheral blood were greatly diminished in the CsA-treated animals. Sera from rats treated with CsA also were capable of inhibiting in vitro proliferative responses. These findings demonstrate that CsA-treated Lewis rats have alterations in several cell-mediated immune functions, thereby not permitting full development of the immune events that ultimately lead to uveitis.