Kids Research Express

. Autoimmunity is the immune response of the body turned against its own cells and tissues. Autoimmune diseases may involve either cell-mediated responses, humoral responses, or both. For example, in Type 1 diabetes , the body makes an immune response against its insulin-producing cells and destroys them, with the result that the body cannot use sugars. In myasthenia gravis , the immune system makes antibodies against the normal molecules that control neuromuscular activity, causing weakness and paralysis . In rheumatic fever , the immune system makes antibodies that bind to the heart’s valves, leading to permanent heart damage. In systemic lupus erythematosus , commonly known as lupus, the body makes antibodies against many different body tissues, resulting in widespread symptoms. The mechanisms of autoimmune diseases are poorly understood, and thus the basis for autoimmunity is unclear. Much research focuses on trying to understand these mechanisms and should eventually result in cur...

Autoimmune Diseases, illnesses in which the immune system reacts to normal components of the body as if they were foreign substances and produces antibodies against them. Antibodies are manufactured by cells called lymphocytes. It is thought that, during development of the embryo, lymphocytes capable of reacting with the body's own tissues are somehow inactivated so that the self is distinguished from the nonself and is not destroyed by antibodies. Self-reactive lymphocytes can still be found in some adults, however, which suggests that they are actively suppressed in some way rather than eliminated. Another mechanism for protecting components of the self from destruction is sequestration during early development. Mature sperm cells, for example, do not appear until after the immune system has matured and are then automatically separated from the bloodstream. After vasectomy, these cells enter the bloodstream, where they can provoke formation of antibodies against themselves (auto...