Lymphocyte subpopulations in Graves' ophthalmopathy

We assessed the percentages of T-lymphocyte subsets, B lymphocytes, monocytes, and granulocytes in the mononuclear cell preparations of euthyroid patients with minimal and severe Graves' ophthalmopathy. Patients with active Werner class 4-5 and class 6 ophthalmopathy had statistically significant elevations of suppressor/cytotoxic T8+ lymphocytes. During successful corticosteroid therapy, the number of T8+ lymphocytes returned to the normal range. Mirroring these results, the T4/T8 ratio was initially depressed in patients with class 4-5 ophthalmopathy and increased during therapy. Our previous observations noted a decreased number of rosette-forming T lymphocytes in patients with severe ophthalmopathy. In this study, however, there were normal percentages of T3+ and T11+ lymphocytes, suggesting that the T lymphocytes are present in peripheral blood but they cannot form rosettes. There was a slight reduction of the percentage of the T11+ (erythrocyte receptor) lymphocytes in the patients with class 4-5 ophthalmopathy; however, it was not statistically significant. No significant differences were evident in any of the other T-lymphocyte subsets, B lymphocytes, monocytes, or granulocytes studied. We conclude that Graves' ophthalmopathy is characterized by a surface membrane defect associated with increased percentages of suppressor/cytotoxic T8+ lymphocytes. Successful corticosteroid therapy reverses these findings.