2-COLOR FLOW CYTOMETRIC ANALYSIS OF ACTIVATED T-LYMPHOCYTES IN AQUEOUS-HUMOR OF PATIENTS WITH ENDOGENOUS VS EXOGENOUS UVEITIS

To investigate the immunopathologic role of lymphocytes in aqueous hum or of patients with uveitis, we assessed activated T lymphocyte subset s stained with fluorescein isothiocyanate-labeled and phycoerythrin-la beled monoclonal antibodies in aqueous humor and in peripheral blood, using two-color flow cytometry. We divided our 25 patients into those with endogenous or exogenous uveitis. The percentages of activated T l ymphocytes in uveitic aqueous humor significantly exceeded those in pe ripheral blood lymphocytes from patients with either disease form. CD4 (+)HLA-DR(+) lymphocytes were predominant in endogenous uveitic aqueou s humor, whereas CD8(+)HLA-DR(+) lymphocytes predominated in exogenous uveitic aqueous humor in the early stage of the disease. The percenta ges of CD4(+)HLA-DR(+) lymphocytes tended to increase while those of C D8(+)HLA-DR(+) cells tended to decrease in aqueous humor from patients in the late phase of exogenous uveitis. Our results may contribute to increasing diagnostic accuracy in patients with uveitis and to develo ping more rational methods of treatment.