Section 866.5080 - Alpha-1-antichymotrypsin immunological test system(a)Identification. An alpha-1-antichymotrypsin immunological test system is a device that consists of the reagents used to measure by immunochemical techniques alpha-1-antichymotrypsin (a protein) in serum, other body fluids, and tissues. Alpha-1-antichymotrypsin helps protect tissues against proteolytic (protein-splitting) enzymes released during infection.(b)Classification. Class II (performance standards).