Anti-endomysial antibodies

Anti-transglutaminase antibodies (ATA) are autoantibodies against the transglutaminase protein. Antibodies serve an important role in the immune system by detecting cells and substances that the rest of the immune system then eliminates. These cells and substance can be foreign (for example, viruses) and also can be produced by the body (for example, cancer cells). Antibodies against the body's own products are called autoantibodies. Autoantibodies can sometimes errantly be directed against healthy portions of the organism, causing autoimmune diseases.

ATA can be classified according to 2 different schemes: transglutaminase isoform and immunoglobulin reactivity subclass (IgA, IgG) toward transglutaminases.

Antibodies to tissue transglutaminase (abbreviated as anti-tTG or anti-TG2) are found in patients with several conditions, including coeliac disease, juvenile diabetes,inflammatory bowel disease, and various forms of arthritis.

In coeliac disease, ATA are involved in the destruction of the villous extracellular matrix and target the destruction of intestinal villous epithelial cells by killer cells. Deposits of anti-tTG in the intestinal epithelium predict coeliac disease.

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