About this Book

Presence of autoantibodies is usually a sign of autoimmune disease, although low levels of autoantibodies may also be found in healthy individuals. The discovery of autoantibodies and their associations with autoimmune disease have improved the knowledge of disease mechanisms in autoimmunity as well as clinical diagnostics over the years. Lack of immune tolerance and increased production of antibodies directed against self-antigens may induce or drive autoimmune disease as clearly demonstrated for TSH receptor antibodies in Graves’ disease. Autoantibodies could also be a biomarker of an autoimmune disease, but without distinct pathophysiologic relevance; this could be exemplified by smooth muscle antibodies (SMA) in autoimmune hepatitis. Most autoimmune diseases, e.g., systemic lupus erythematosus, myositis and Sjögren’s syndrome, are however characterized by a mixture of autoantibodies of varying degrees of pathogenic potentiality, and which can be used to guide the physician to a correct diagnosis or prognosticate disease severity, disease manifestations, or response to treatments.

Neither the discovery of autoantibodies nor their connection to autoimmune diseases constitutes new knowledge. However, new autoantibodies of clinical relevance are continuously discovered, and novel application areas for “old” autoantibodies appear. Since autoantibodies may aid clinical decisions regarding diagnostics, follow-up, prognostics, and tailored treatment strategies, it is of importance to optimize the use of known autoantibodies as well as to discover new autoantibodies of clinical relevance.