[Investigations of interferon and oligo-2',5'-adenylate systems in endogenous uveitis]

The interferon (IFN) and oligo-2',5'-adenylate (2-5A) systems were investigated in endogenous uveitis. It was shown that oligo-2',5'-adenylate synthetase (2-5AS) activities of peripheral blood lymphocytes (PBL) were significantly increased in Behcet's disease (P less than 0.01), Vogt-Koyanagi-Harada's disease (VKH disease, P less than 0.01), and sarcoidosis (P less than 0.01) compared with those in controls. In order to investigate the effect of cyclosporin A (Cy A) on IFN systems in Behcet's disease, 2-5AS activities of PBL from 2 patients under Cy A therapy (10 mg/kg/day) were examined. The enzyme activities were high before treatment in both patients, but the activities were suppressed after treatment. The effect of Cy A on the production of IFN by PBL in vitro was also examined. IFN synthesis was markedly suppressed by Cy A in patients and controls. The effect of corticosteroids on IFN and 2-5A systems in VKH disease was studied. Two patients were given 200 mg of prednisolone with gradual tapering. Activities of 2-5AS of PBL from patients were high before treatment, and they were markedly suppressed after prednisolone treatment. The serum IFN, 2-5AS activities of PBL and the synthesis of IFN in vitro were examined in one patient who was given pulse methylprednisolone therapy. The serum IFN and 2-5AS activity of PBL were suppressed by this therapy. The production of IFN-alpha induced by herpes simplex virus and IFN-gamma induced by staphylococcal enterotoxin A and OK-432 were greatly suppressed. These results suggest that the IFN and 2-5A systems in endogenous uveitis play some significant role in the immunopathophysiology of these diseases.