DOMINANCE OF ACTIVATED T-CELLS AND INTERLEUKIN-6 IN AQUEOUS-HUMOR IN VOGT-KOYANAGI-HARADA DISEASE

Purpose. To determine the immunopathologic role of the lymphocytes and lymphokines in aqueous humor (AH) of patients with Vogt-Koyanagi-Hara da disease (VKH). Methods. The distribution of leukocyte subsets in th e peripheral blood and AH was examined using fluorescein isothiocyanat e-conjugated monoclonal antibodies. The levels of lymphokines, such as interleukin-2 (IL-2) and interleukin-6 (IL-6), in the sera, AH, and c erebrospinal fluid from the patients with VKH were determined using an enzyme-linked immunosorbent assay. Results. T cells constituted the m ajority of lymphocytes within AH. The value for CD4(+) cells (helper/i nducer T lymphocytes) in AH was 51.7% +/- 14.9% (mean +/- SD) and that for CD8(+) cells (cytotoxic/suppressor T lymphocytes) was 31.1% +/- 1 3.0%. The percentage of HLA-DR(+) cells (B lymphocytes, monocytes, mac rophages; and activated T lymphocytes) in AH (50.8% +/- 24.9%) signifi cantly exceeded (P < 0.001) that in blood (13.1% +/- 4.2%). The percen tage of CD8(+) cells in AH from three patients with the delayed type o f VKH rose during their clinical course. The level of IL-6 was signifi cantly elevated in AH from the patients with VKH. The level of IL-6 in AH correlated with the number of lymphocytes in AH, and it reflected the severity of the inflammatory response in AH of patients with VKH. The level of IL-2 in the sera, AH, and cerebrospinal fluid was in the normal range. Conclusions. Aqueous humor lymphocytes from the patients with VKH were more activated than were peripheral blood lymphocytes. IL-6 may play an important role as an inflammatory mediator in VKH. lt may be useful to analyze the lymphocyte subsets and the levels of lym phokines, especially of IL-6, at the site of inflammation in uvea to i mprove the criteria for assessing the prognosis of VKH.