Gamma globulin is one of the classes of proteins found in blood plasma. Gamma globulins play an important role in the body’s disease-fighting immune system, and are also known as immune globulins. Most of the antibodies (infection-fighting proteins) in the body fluids are gamma globulins. White blood cells called lymphocytes produce antibodies after coming into contact with such harmful substances as bacteria or viruses. The antibodies react with and help destroy the invading germs.
The gamma globulin in a person’s plasma consists of the various antibodies produced by that individual. A mixture of plasma from many blood donors contains a wide variety of antibodies, because it includes the combined gamma globulin of all the donors. Drug manufacturers separate the gamma globulin from such a mixture and purify it for medical use. Physicians use gamma globulin injections to prevent or treat certain infectious diseases, including measles and viral hepatitis. Gamma globulin is also administered to people who cannot produce enough antibodies and to some patients who have low blood platelet counts because of autoimmune diseases.
