Blood mononuclear cells with suppressor activity in patients with thyroid disorders: increased levels of T gamma cells in subacute thyroiditis.

Blood T lymphocytes with suppressor activity [stable T cells, low affinity T cells and T cells with Fc receptors for IgG (T gamma cells)] were enumerated, using rosette tests, in patients with Graves' hyperthyroidism, Hashimoto's thyroiditis, silent thyroiditis, primary hypothyroidism, Graves' ophthalmopathy and subacute thyroiditis. General suppressor function, assessed as inhibition of pokeweed mitogen induced plasma cell generation by concanavalin-A stimulated T cells was measured in patients with Graves' hyperthyroidism, Hashimoto's thyroiditis and subacute thyroiditis. Suppressor T cell numbers were found to be essentially normal in patients with Graves' hyperthyroidism, Hashimoto's thyroiditis, Graves' ophthalmopathy, silent thyroiditis and hypothyroidism, although % T gamma cells were increased in 5 of the 7 patients with subacute thyroiditis tested. Suppressor cell function was normal in patients with graves' hyperthyroidism, Hashimoto's thyroiditis and subacute thyroiditis. It is likely that the putative deficiency of suppressor T cells in thyroid autoimmunity is restricted to a few clones of cells allowing retention of thyroid directed effector cells. The mechanism for increased T gamma cells in subacute thyroiditis is unclear although likely to reflect either a physiological response to sensitization following thyroid antigen release or a non-specific effect of the viral infection.