Autoantibodies that are directed against self antigens are called autoantibodies. Not all autoantibodies are harmful. Autoantibodies can be useful in the removal of cell debris during inflammation. Some autoantibodies may be the actual pathogenic agents of autoimmune disease, the secondary consequences of tissue damage, or the harmless footprints of an etiologic agent. In this book, the authors present current research in the detection, pathogenicity and health implications of autoantibodies. Topics include the implicated autoantibodies in kidney disease and Alzheimer’s disease; autoimmunity in cardiovascular disease; detection and analysis of natural autoantibodies; and B Cells and autoantibodies in multiple sclerosis.