Autoantibodies (syn. autoimmune antibodies) are antibodies produced by the body's immune system against its own antigens. The formation of autoantibodies occurs in autoimmune diseases when the immune system mistakenly recognizes normal cells and proteins in the body as foreign and begins to produce antibodies against them.
Autoantibodies can destroy tissue and impair the functions of various organs. For example, in rheumatoid arthritis, autoantibodies are produced against components of the joints, leading to inflammation and destruction of cartilage. In type 1 diabetes, autoantibodies are formed against the pancreatic cells that produce insulin.
Determining the level of various autoantibodies in the blood is an important diagnostic test for autoimmune diseases. For example, the detection of antibodies to double-stranded DNA is used to diagnose systemic lupus erythematosus.
Thus, autoantibodies play a key role in the development of autoimmune processes and serve as important markers of these diseases. Their detection helps in making the correct diagnosis and monitoring the effectiveness of treatment.