Anti-mitochondrial antibody

Anti-mitochondrial antibodies (AMA) are antibodies (immunoglobulins) formed against mitochondria, primarily mitochondria in cells of the liver. The presence of AMAs in the blood or serum of a person is indicative of a disease called primary biliary cirrhosis (PBC) (a scarring of liver tissue, confined primarily to the bile duct drainage system of the liver). It is present in about 95% of cases.

Primary biliary cirrhosis is seen primarily in middle-aged women, and in those afflicted with other autoimmune diseases. PBC is an autoimmune disorder, a condition in which the human body's immune defense system mistakenly attacks the body's own cells, or in this case parts of the cells.

Cause of AMAs is postulated that xenobiotic-induced and/or oxidative modification of mitochondrial autoantigens is a critical step leading to loss of tolerance. In acute liver failure AMA are found against all major liver antigens.
 * pyruvate dehydrogenase, E2 subunits
 * 2-oxo-glutarate dehydrogenase
 * branched chain 2-oxo-acid dehydrogenase

Anti-cardiolipin antibodies are another type of AMA, cardiolipin is found on the inner mitochondrial membrane.

Correlation with non-mitochodrial antigens
Fifty seven percent of acute liver failure patients had elevated anti-transglutaminase antibodies (anti-tTG), which correlate with gluten-sensitive enteropathy (see coeliac disease, Gluten-sensitive enteropathy associated conditions). The inflammation produced by gluten-sensitive cellular immunity may cause the oxidative stress resulting in the modification of mitochondrial antigens and acute liver failure. Anti-gp210 antibodies are also found in 47% of PBC patients.