autoantibodien

Autoantibodies are antibodies produced by the immune system that target self-antigens. They are a hallmark of autoimmune diseases but can be found in healthy individuals, especially with age or certain environmental exposures. Autoantibodies can be directed against intracellular components such as nuclear antigens, or against cell surface or secreted proteins.

Their development reflects a loss of immune tolerance. Genetic susceptibility interacts with environmental factors, infections, and immune regulation to activate autoreactive B cells. B cells may undergo maturation in germinal centers with help from T helper cells, promoting class switching to IgG or other isotypes. Some autoantibodies arise transiently after infections, while others persist long term.

Autoantibodies may be pathogenic, contributing to disease by blocking or stimulating receptors or by forming immune complexes that cause tissue inflammation. Others primarily serve as diagnostic markers or indicators of disease activity. Examples include anti-dsDNA and anti-Smith antibodies in systemic lupus erythematosus, anti-thyroid peroxidase and anti-thyroglobulin antibodies in autoimmune thyroid disease, anti-desmoglein antibodies in pemphigus, and acetylcholine receptor antibodies in myasthenia gravis. Antiphospholipid antibodies are associated with thrombosis and pregnancy complications.

Clinically, serologic testing for autoantibodies is integral to diagnosis and management. Panels may include ANA screens, anti-dsDNA, anti-Smith, anti-CCP, rheumatoid factor, and organ-specific antibodies. Autoantibody profiles help guide diagnosis, prognosis, and treatment decisions and may be used to monitor disease activity in certain conditions.

Therapeutically, strategies aim to reduce autoantibody production or remove circulating antibodies, including immunosuppression, B cell–targeted therapies, and plasmapheresis in selected cases.