Alpha 1-antichymotrypsin

Alpha 1-antichymotrypsin (α1AC) is an is_associated_with::alpha globulin is_associated_with::glycoprotein that is a member of the is_associated_with::serpin superfamily. In humans, it is encoded by the SERPINA3 is_associated_with::gene.

Function
Alpha 1-antichymotrypsin inhibits the activity of certain is_associated_with::enzymes called is_associated_with::proteases, such as is_associated_with::cathepsin G that is found in is_associated_with::neutrophils, and is_associated_with::chymases found in is_associated_with::mast cells, by cleaving them into a different shape or conformation. This activity protects some tissues, such as the is_associated_with::lower respiratory tract, from damage caused by proteolytic enzymes.

This protein is produced in the is_associated_with::liver, and is an is_associated_with::acute phase protein that is induced during is_associated_with::inflammation.

Clinical significance
Deficiency of this protein has been associated with is_associated_with::liver disease. Mutations have been identified in patients with is_associated_with::Parkinson disease and is_associated_with::chronic obstructive pulmonary disease.

Alpha 1-antichymotrypsin is also associated with the is_associated_with::pathogenesis of is_associated_with::Alzheimer's disease as it enhances the formation of amyloid-fibrils in this disease.

Interactions
Alpha 1-antichymotrypsin has been shown to interact with is_associated_with::DNAJC1.