Thyroglobulin

Thyroglobulin is a 660 kDa dimeric glycoprotein produced by follicular cells of the thyroid. It is a precursor of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). Thyroglobulin has a high affinity for iodine, which it incorporates into its structure during the production of T3 and T4.

In thyroid disease, thyroglobulin is up- or down-regulated in a number of conditions. Elevated levels of thyroglobulin are found in thyroid cancer, thyroiditis, goiter, and hyperthyroidism diseases such as Graves's disease. Low levels are found in hypothyroidism and some autoimmune disorders like Hashimoto's disease. In addition, the presence of anti-thyroglobulin antibodies in the body may be an indication of certain autoimmune diseases and cancers.