Purpose: To investigate the capacity of the recombinant gamma-subunit (P gamma) of cyclic guanosine monophosphate phosphodiesterase to induce experimental autoimmune uveoretinitis in Lewis rats.
Methods: Bovine P gamma was expressed in Escherichia coli cells and purified by fast protein liquid chromatography. Lewis rats were immunized by a single footpad injection of P gamma emulsified in complete Freund's adjuvant. Clinical and histopathologic changes in the eye and pineal gland were examined. Lymphocytes were prepared from the lymph nodes of rats with uveitis and transferred by intraperitoneal injection to naive recipient rats.
Results: Immunization of rats with P gamma induced panuveitis and pinealitis with clinical and histopathologic changes similar to those induced by S-antigen. Lymphocytes from the lymph nodes of diseased rats transferred uveitis to naive recipients.
Conclusions: P gamma, a retina-specific protein of molecular weight less than 10,000 kDa, is capable of inducing uveoretinitis in Lewis rats. The disease can be transferred adoptively to naive rats by injection of lymphocytes from donor rats with experimental autoimmune uveoretinitis. Inflammation of the pineal gland of immunized rats suggests that P gamma is not only localized to the retina but also to the pineal gland.