Autoimmune Pathogenesis in Thyroid Diseases

Abstract

Many evidences have been presented that autoimmunity plays a major part in the pathogenesis of thyroid diseases. Autoimmunity in thyroid diseases shows up as clinical and laboratory findings of disordered humoral and cellular immunity and immunogenetic background of the patients. So, to make clear the significance of humoral immunity in the autoimmune pathogenesis of thyroid diseases, most of the autoantibodies found in autoimmune thyroid diseases are discussed about their characteristics and implications. Especially in Graves' disease patients, TSH receptor antibodies are now considered to playa causative role in the genesis of disease. Our data about every aspect of these antibodies are presented. In the patients with primary myxedema TSH receptor antibodies are suspected to behave themselves as a blocker of TSH action. Then the author presents our findings about blocking TSH receptor antibodies. Cellular immunity influences the immune tolerance to self antigens in the patients with autoimmune thyroid diseases. The author reviews the roles of cellular immunity in the autoimmune thyroid diseases in the aspects of the disordered functions of the cellular immunity and its further regulatory roles in the humoral immunity, presenting our data about the functional aberrations of the regulatory immunocytes and thyrocytes. Genetic and immunogenetic background of the patients with autoimmune thyroid diseases are then reviewed with the data on HLA and disease association in Koreans, analyzing their significance in the pathogenesis of autoimmune thyroid diseases. The author suggests the possible mechanisms in the autoimmune pathogenesis in thyroid diseases with the present findings.