TPO ELISA kits are assays designed to detect the enzyme thyroid peroxidase. Also called iodide peroxidase, it is secreted by the human thyroid gland and catalyzes the oxidation of iodide to iodine for the production of thyroxine and triiodothyronine. It is approximately 100 kDa and has two known isoforms, hTPO-1 and hTPO-2. Variants of TPO have been associated with autoimmune hypothyroidism. Visit the supplier page for more information about detection range and reactivity.