Thyroid Peroxidase Antibodies (TPO) Unit Converter

Thyroid peroxidase antibodies (TPO-Ab) are proteins produced by your immune system that mistakenly target thyroid peroxidase, an enzyme essential for making thyroid hormones.

Thyroid peroxidase (TPO) is found on the surface of thyroid cells and plays a critical role in producing the thyroid hormones T3 and T4. When the immune system produces antibodies against TPO, it can interfere with normal thyroid hormone production and lead to thyroid dysfunction.

TPO antibodies are the primary marker for autoimmune thyroid diseases. They are present in approximately 90% of people with Hashimoto's thyroiditis and 60-80% of people with Graves' disease. However, about 10-15% of the general population may have detectable TPO antibodies without any thyroid symptoms.

TPO antibodies are produced by B lymphocytes (immune cells) within and around the thyroid gland. The antibodies target thyroid peroxidase, an enzyme located on the surface of thyroid follicle cells that is essential for producing thyroid hormones.