Autoimmune Diseases
Much has been said about autoimmune diseases and many more worldwide are suffering from these dreadful diseases. Autoimmune diseases, totaling about 80 serious types, arise from an overactive immune response of the body against substances (micro-organisms, parasites such as worms, cancer cells, and even transplanted organs and tissues) and its own tissues and organs. Even cells in a person's own tissues can have antigens. But, normally, the immune system reacts only to antigens from foreign or dangerous substances, not to antigens from a person's own tissues. However, the immune system sometimes malfunctions, interpreting the body's own tissues as foreign and producing antibodies (called autoantibodies) or immune cells that target and attack particular cells or tissues of the body. This response is called an autoimmune reaction. It results in inflammation and tissue damage. Such effects may constitute an autoimmune disorder, but some people produce such small amounts of autoantibodies that an autoimmune disorder does not occur. Some of the more common autoimmune disorders include rheumatoid arthritis, systemic lupus erythematosus (lupus), and vasculitis, among others. Additional diseases that are believed to be due to autoimmunity include glomerulonephritis, Addison's disease, mixed connective tissue disease, polymyositis, Sjögren's syndrome, progressive systemic sclerosis, and some cases of infertility.
Autoimmune reactions can be triggered in several ways. A substance in the body that is normally confined to a specific area (and thus is hidden from the immune system) is released into the bloodstream. For example, a blow to the eye can cause the fluid in the eyeball to be released into the bloodstream. The fluid stimulates the immune system to recognize the eye as foreign and attack it. When a normal body substance is altered, for example, by a virus, a drug, sunlight, or radiation, the altered substance may appear foreign to the immune system. Take for example, a virus can infect and thus alter cells in the body. The virus-infected cells stimulate the immune system to attack. Similarly a foreign substance that resembles a natural body substance may enter the body. The immune system may inadvertently target the similar body substance as well as the foreign substance. In this case, as an example, the bacteria that cause strep throat have some antigens that are similar to those in human heart cells. Rarely, the immune system may attack a person's heart after strep throat (this reaction is part of rheumatic fever). In certain other cases, the cells that control antibody production, B lymphocytes (a type of white blood cell) may malfunction and produce abnormal antibodies that attack some of the body's cells. In all cases, the underlying problem is similar where the body's immune system becomes misdirected and attacks the very organs it was designed to protect. In short, the immune system cells attack its other own cells. Heredity may be involved in some autoimmune disorders. Susceptibility to the disorder, rather than the disorder itself, may be inherited. In susceptible people, a trigger, such as a viral infection or tissue damage, may cause the disorder to develop. Hormonal factors may also be involved, because many autoimmune disorders are more common among women.
Autoimmune disorders symptoms may vary and cause a fever; depending on the disorder and the part of the body affected. Some autoimmune disorders affect certain types of tissue throughout the body such as the blood vessels, cartilage, or skin. Other autoimmune disorders affect a particular organ. Virtually any organ, including the kidneys, lungs, heart, and brain, can be affected. The resulting inflammation and tissue damage can cause pain, deformed joints, weakness, jaundice, itching, difficulty breathing, accumulation of fluid (edema), delirium, and even death.
It has been estimated that autoimmune diseases are among the ten leading causes of death among women in all age groups up to 65 years. Women seem to be the dominant group of sufferers with a ratio of 3:1 against men sufferers. Adolescent or young adults are typical patients while it is uncommon for the elderly. Known to strike women particularly those of working age and during their childbearing years. Some autoimmune diseases occur more frequently in certain minority populations. Lupus is more common in African-American and Hispanic women than in Caucasian women of European ancestry. Rheumatoid arthritis and scleroderma affect a higher percentage of residents in some Native American communities than in the general U.S. population. In total, 23.5 million Americans have an autoimmune disease as compared to 9 million Americans for cancer. Worldwide numbers are not known due to lack of statistics recorded but autoimmune diseases will be expected to increase dramatically in the next decade to come because of a number of factors, including increasing environmental pollution, thus allowing for even more opportunity in this market. Advances in biotechnology are also enriching research work in this area. Secondary to cancer and infectious diseases, autoimmune diseases is the therapeutic category with the most number of biotech drugs under development.
Treatment therapies which have failed to cure auto-immune diseases have driven the need for creation and development of innovative and meaningful bio-therapeutics to address important unmet medical needs in these areas. Considerable research is being conducted worldwide to develop more effective drugs for asthma, allergies, inflammation and other diseases that affect the human immune system, but there are certain medical needs in these areas which demand the development of highly efficient and safe therapeutic agents for optimal use in man.
Blood tests, a combination of other test and the person's signs and symptoms usually are adopted to decide whether an autoimmune disorder is present. Treatment involves control of the autoimmune reaction by suppressing the immune system. However, many of the drugs used to control the autoimmune reaction also interfere with the body's ability to fight disease, especially infections. Oral drugs that suppress the immune system (immunosuppressants), such as azathioprine, chlorambucil, cyclophosphamide, cyclosporine, mycophenolate and methotrexate are often given for a long time. However, these drugs suppress not only the autoimmune reaction but also the body's ability to defend itself against foreign substances, including microorganisms that cause infection and cancer cells. Consequently, the risk of certain infections and cancers increases. Very often, corticosteroids, such as prednisone are given orally as well. These drugs relieve inflammation as well as suppress the immune system. Corticosteroids given for a long time have many side effects. Whenever possible, corticosteroids are used for a short time when the disorder begins or when symptoms worsen. However, corticosteroids must sometimes be used indefinitely. Certain autoimmune disorders (for example, multiple sclerosis and thyroid disorders) are also treated with drugs other than immunosuppressants and corticosteroids. Treatment to relieve symptoms may also be needed. Infliximab and adalimumab block the action of tumor necrosis factor (TNF), a substance that can cause inflammation in the body. These drugs are very effective in treating rheumatoid arthritis, but they may be harmful if used to treat certain other autoimmune disorders, such as multiple sclerosis and can also increase the risk of infection and certain cancers. Certain new drugs specifically target white blood cells. White blood cells help defend the body against infection but also participate in autoimmune reactions. Abatacept blocks the activation of one kind of white blood cell (T cell) and is used in rheumatoid arthritis. Rituximab, first used against certain white blood cell cancers, works by depleting certain white blood cells (B lymphocytes) from the body. It is effective in rheumatoid arthritis and is under evaluation in a variety of autoimmune disorders. Other agents directed against white blood cells are being developed. Plasmapheresis is used to treat a few autoimmune disorders. Blood is withdrawn and filtered to remove the abnormal antibodies. Then the filtered blood is returned to the person.
Some autoimmune disorders resolve as inexplicably as they began. However, most autoimmune disorders are chronic to prevent healthy lifestyles. Drugs are often required throughout life to control symptoms. The prognosis varies depending on the disorder. Alternative approach is now being researched with some already in the market; amongst which are stem cells therapy StemEnhance and immune system modulator Transfer Factor
