TSHR and autoimmune thyroid disease: Other anti-thyroid immunoglobulins may also be detected in patients with autoimmune thyroiditis: TSH receptor blocking or stimulating antibodies (TSHRAb), antibodies to thyroxine, triiodothyronine, megalin (a transmembrane protein belonging to the low-density lipoprotein receptor family), pendrin (anion transport protein SLC26, carrying iodide ions to the colloid) or against sodium-iodide symporters (anion transport protein SLC5A catalyzes the active transport of iodide ions from the blood into the thyroid).