In order to study the etiology and pathogenesis of thyroid disorders, immunologic tests for thyroid disorders have been included as part of the screening program for certain thyroid disorders. Thyroid Peroxidase Antibody ( TPOAb)Thyroid Peroxidase Antibody ( TPOAb) is the main component of the former Thyroid Microsomal Antibody (TMAb), which is a group of polyclonal antibodies directed against different antigenic determinants, with a predominance of the IgG type.Clinical application of TPOAb assay:Diagnosis of autoimmune thyroid diseases, such as autoimmune thyroiditis and Graves’ disease. Graves’ disease, etc. Thyroglobulin antibodies ( TgAb ) TgAb is a group of polyclonal antibodies against different antigenic determinants of thyroglobulin, mainly of the IgG type, but also of the IgA and IgM types. It is generally believed that TGAb has no detrimental effect on the thyroid gland.Clinical applications of TgAb: (1) Diagnosis of autoimmune thyroid disease: its significance is basically the same as that of TPOAb, and the change of antibody titer is also consistent; (2) Differentiated thyroid cancer (DTC): serum TgAb is mainly used as an auxiliary examination for serum TG measurement.TPOAb and TgAb are important indicators and indicators for determining the cause of primary hypothyroidism, and also for determining the cause of primary hypothyroidism. TPOAb and TgAb are important indicators for determining the etiology of primary hypothyroidism and for diagnosing autoimmune thyroiditis (including Hashimoto’s thyroiditis and atrophic thyroiditis).Significantly elevated titers of TPOAb and TgAb antibodies are one of the characteristics of Hashimoto’s disease, especially in those with elevated serum TSH levels. Thyroid Hormone Receptor Antibodies Thyrotropin Receptor Antibodies ( TRAb antibodies), also known as Thyroid Stimulating Antibodies ( TSAb ), are produced during autoimmunization of a toxic diffuse goiter and stimulate the production of thyroid hormone by the thyroid gland.The TSAb is the causative antibody in Graves’ disease, and this antibody indicates that the cause of hyperthyroidism is TSAb is a pathogenic antibody in Graves’ disease, which indicates that the cause of hyperthyroidism is Graves’ disease; the TSAb positivity rate in Graves’ disease is as high as 85.7%, while other causes of hyperthyroidism are generally negative.TSAb is a reference indicator for determining the efficacy and prognosis of immunological remission during the course of treatment with antithyroid drugs. If TSAb is negative after treatment with antithyroid drugs, the drug should be stopped.TSAb is positive, indicating that it is easy to relapse after stopping the drug.TSAb can cause neonatal hyperthyroidism through the placenta, so it has a predictive effect on neonatal hyperthyroidism.