(1) Any of a group of proteins synthesized by the body when invaded by infective organisms. They are coagulated by heat; insoluble in water; soluble in dilute solutions of salts, strong acids, and strong alkalies. Enzymes and acids cause hydrolysis to amino acids as the only products. Examples are immune serum or γ-globulins in blood and myosin in muscle. The blood globulins are used in immunizing against specific diseases and in medical research. The γ-globulin molecule is reported to consist of 19,996 atoms associated in 1320 amino acid units.(2) A protein occurring naturally in wheat and other cereal grains.See Immunochemistry.