The immune system is essential to survival, and even a modest decrease in immune function can leave a person susceptible to infection. But the immune system itself can also cause disease, by inappropriately attacking the body’s own organs, tissues, or cells. Autoimmune diseases are often disabling illnesses that develop when underlying defects in the immune system lead the body to attack its own organs, tissues, and cells. To date, there have been more than 100 autoimmune diseases identified. Some, such as type 1 diabetes, attack specific organs, while others, such as systemic lupus erythematosus (SLE), involve multiple organs. Some of the prevalent autoimmune diseases include Multiple Sclerosis, Myasthenia Gravis, Scleroderma, Polymyositis, Vasculitis, Lupus (SLE & Discoid), and Idiopathic Thrombocytopenic Purpura (ITP), Juvenile Diabetes, Sjögren’s disease, Crohn’s disease and Grave’s disease. Autoimmunity is the underlying cause of these diseases and although some autoimmune disease are considered rare, according to the Autoimmune Diseases Coordinating Committee (ADCC), between 14.7 and 23.5 million people in the USA–up to eight percent of the population–are affected by autoimmune disease.  For unknown reasons, the prevalence of autoimmune disease is increasing. Despite autoimmune disease being the 3^rd major cause of illness behind cancer and heart disease, little progress has been made in the treatment of autoimmune disease. Although researchers have made some progress in understanding the immune mechanisms that mediate tissue injury in autoimmune diseases, much remains to be learned.