Antithyroid antibodies and autoimmune diseases of the thyroid

Abstract

The significance and mechanisms of action of different antithyroid antibodies in diffuse toxic goiter (Graves' disease) and chronic lymphocytic thyroiditis (Hashimoto’s disease) arc analyzed. Antibodies immediately decreasing the level of cAMP in isolated thyrocytes were revealed in the sera of adolescents with juvenile struma, often resulting from lymphocytic thyroiditis. Complement-fixing cytotoxic antibodies are heterogeneous in patients with Graves' diseases and Hashimoto's thyroiditis. Thyrocytes from the tissue of diffuse toxic goiter are resistant to the cytolytic effect of such antibodies from patients with Graves' diseases but not from patients with Hashimoto's thyroiditis. The causes and mechanisms of development of resistance of thyrocytes from diffuse toxic goiter to antibody-dependent complement-mediated cytotoxicity of sera from patients with Graves' disease and the possibility of using this phenomenon as a differential diagnostic test are discussed.