Thyroid Autoantibodies in Graves’ Disease

Graves’ hyperthyroidism is caused by autoantibodies to the TSH receptor (TSHR) that mimic the stimulatory effects of TSH (reviewed in 1). At the other extreme is Hashimoto’s thyroiditis, in which autoantibodies to thyroid peroxidase (TPO) and sometimes to thyroglobulin (Tg), are associated with (but do not necessarily cause) destruction of thyroid follicular cells and hypothyroidism. Less commonly, atrophic thyroiditis can be caused by TSH receptor antibodies that block TSH action (reviewed in 1). Occasionally, in the same patient, the balance may shift from hyperthyroidism to hypothyroidism, and vice versa.