What is an autoantibody?

An autoantibody is an antibody that is produced by the immune system and directed against the body's own cells, tissues, or organs. Autoantibodies can cause damage to various parts of the body and contribute to the development of autoimmune disorders. Autoimmune disorders are a group of disorders in which the immune system mistakenly attacks and damages the body's own tissues. Examples of autoimmune disorders include rheumatoid arthritis, lupus and type 1 diabetes. Autoantibodies can be directed against many different types of molecules and can target different parts of the body, depending on the autoimmune disorder. Autoantibodies can be detected in the blood through a variety of laboratory tests such as ANA (antinuclear antibody) test.

It is important to note however that the presence of autoantibodies does not necessarily mean that the person has an autoimmune disorder or that they will develop one. Indeed autoantibodies are frequently detected in healthy individuals. Each positive test requires careful interpretation by a rheumatologist prior to the diagnosis being established/rejected.