Incidence of T cell subset imbalance in relatives of Graves' disease patients.

In previous reports we demonstrated imbalances of T cell subsets in patients with autoimmune thyroid disease. In the present investigation, we studied several T cell markers with different functional meaning (Fc gamma-receptors, HLA-Ia antigens, MLR4 and 5/9 antigens) in first degree relatives of Graves' disease patients. Our data suggest that imbalances of circulating T cell subpopulations are apparent only when abnormal hormone levels and/or thyroid autoantibodies are present.