Anti-actin antibodies are found at increased frequency in certain autoimmune diseases and may be of some diagnostic value.

In coeliac disease

Coeliac disease

Coeliac disease , is an autoimmune disorder of the small intestine that occurs in genetically predisposed people of all ages from middle infancy onward...

 anti-actin

Actin

Actin is a globular, roughly 42-kDa moonlighting protein found in all eukaryotic cells where it may be present at concentrations of over 100 μM. It is also one of the most highly-conserved proteins, differing by no more than 20% in species as diverse as algae and humans...

 antibodies correlated with the level of intestinal damage.

In autoimmune hepatitis

Autoimmune hepatitis

Autoimmune Hepatitis is a disease of the liver that occurs when the body's immune system attacks cells of the liver. Anomalous presentation of human leukocyte antigen class II on the surface of hepatocytes, possibly due to genetic predisposition or acute liver infection, causes a cell-mediated...

 anti-actin antibodies correlate with patterns of immune recognition, the pattern of recognition was specific to a small percentage of auto-immune hepatitis type 1 or cryptogenic hepatitis patients.

In gastric cancer anti-actin antibodies were elevated, along with other antibodies
in severe disease with poor outcomes.