Sensitization of T-Lymphocytes in Graves’ and Hashimoto's Diseases*

Abstract

To investigate the sensitization of T-lymphocytes to thyroid antigen in autoimmune thyroid disease, a modified migration inhibition factor test was employed using human peripheral T-lymphocytes. Mononuclear cells from the peripheral blood of patients with untreated Graves'' disease (GD) and Hashimoto''s thyroiditis (HT) and from normal subjects were fractionated into E-rosetting (T-cell-enriched) and non-E-rosetting (B-cell- and monocyte-enriched) fractions. The migration index (MI) of T-lymphocytes from 20 patients with untreated GD and 13 patients with HT in response to either crude human thyroid antigen (88 .mu.g/0.5 ml) or solubilized thyrotropin receptor antigen (20 .mu.g/0.5 ml) was significantly inhibited compared to the unaffected migration of T-lymphocytes from 24 normal subjects. There was no correlation between these results and any thyroid autoantibodies. In GD patients taking propylthiouracil, the MI of T-lymphocytes in response to the thyroid antigens was inhibited in only 4 of 9 cases. The MI of T-lymphocytes from patients with GD and HT, was not inhibited when crude human liver antigen or tuberculin-purified protein derivative was used as a control antigen. There was no significant difference in the MI in response to thyroid antigen between normal persons and patients with GD and HT when the non-T fraction of lymphocytes (B-cell-enriched fraction) was employed. Apparently, the T-lymphocyte is the predominant migrating cell; GD and HT T-lymphocytes are sensitized to thyroid antigen and the thyroid cell membrane preparation may be the appropriate antigen in GD and HT.