Autoimmune disease refers to disorders that occur when the body's immune system attacks and destroys healthy cells of the body itself. These differ from other diseases in which the immune system attacks and destroys foreign antigens such as bacteria or viruses, according to MedlinePlus.Continue Reading
The immune system of the human body relies on specific types of white blood cells for protection against foreign or deleterious substances such as bacteria, viruses, toxins, malignant cells and cells originating outside of the body, explains MedlinePlus. One component of these substances is called an antigen, meaning that the immune system generates an antibody as a reaction against it. These antibodies then attack and destroy the offending cells.
In the case of autoimmune disease, the body's immune system fails to distinguish between these antigens and the healthy cells of the body itself, states MedlinePlus. A reaction occurs in which normal, healthy cells are destroyed by the immune system intended to protect them.
More than 80 types of autoimmune disorders exist, including Addison's disease, Graves' disease, multiple sclerosis, pernicious anemia and rheumatoid arthritis, according to MedlinePlus. In addition to destroying body tissues, autoimmune disorders cause abnormal growth of body organs and changes in their functioning. There is no known cure for autoimmune disease, although there are medicines designed to reduce the abnormal functioning of the immune system.Learn more about Conditions & Diseases