Studies on the aetiology and evaluation of thyroid disease

This thesis is concerned with two broad categories of thyroid related research: the aetiology of autoimmune thyroid disease, and the nuclear basis of thyroid hormone action. Whereas the first is directly related to disease, the research in the second area is intended as a contribution to eventual better understanding of the pathophysiology of thyroid dysfunction, and nonthyroidal illness as it affects thyroid hormone action. The research concerning the aetiology of autoimmune thyroid disease utilized the technique of T lymphocyte migration inhibition testing and was designed to test the hypothesis of suppressor T cell deficiency as a pathogenetic mechanism in autoimmune thyroid disease. Migration of T lymphocytes in the presence or absence of specific antigen was displayed by projection microscopy and measured by planimetry. Inhibition in response to thyroid antigen was found in Graves' disease (GD) and Hashimoto's thyroiditis (HT) but not in normal individuals. The addition of a low ratio of normal T lymphocytes to the GD or HT T lymphocytes abolished the migration inhibition whereas admixture with other GD or HT lymphocytes did not, suggesting the possibility that a specific T lymphocyte deficit, i.e. in suppressor cell function, was being corrected.