Dr. Marie Metlay Immunology Paper
Biological Agents and their use in Autoimmune Disease
Autoimmune diseases are from an overactive immune response against the bodies’ own tissues, organs and self-cells. In other words, the body actually attacks its own cells. A part of the body is mistakenly attacked by the immune system thinking that it is a pathogen. This can be isolated to just one organ or tissue in the body, or can be systemic. There are many different types of autoimmune diseases, such as Rheumatoid Arthritis and Colitis, but one disease imparticular that will be mentioned in this paper is Crohns Disease. The main focus of this paper is Biological therapy and its use in treatment of autoimmune disease.
When dealing with autoimmune disease there are three main approaches to its treatment. First, reduce the tissue injury caused by an inflammatory autoimmune response. This is typically accomplished with anti-inflammatory drugs such as Aspirin, NSAID’s and corticosteroids. Second, treatment can be directed specifically at compensating for the impaired physiological function. An example of this is seen in diabetics when they inject insulin into there bodies to balance their glucose levels. And thirdly, therapy can be aimed at modifying and reducing the autoimmune response. This treatment is the main focus of the paper and it is called Biological Therapy.
Biological therapy is the treatment to stimulate or restore the ability of the immune system to fight infection and disease. Thus any form of treatment that uses the body's natural abilities to fight infection and disease or to protect the body from some of the side effects of treatment, would be considered a form of biological therapy. Biological therapy often employs substances called biological response modifiers (BRMs). These include monoclonal antibodies, interferon, interleukin-2 (IL-2), and several types of colony- stimulating factors. One of the most common BRM is Tumor Necrosis Factor (TNF).
TNF is a cytokine (chemical substances which deliver messages between cells in the body) involved in systemic inflammation. It induces necrosis (death) of tumor cells and possesses a wide range of pro-inflammatory actions. Tumor necrosis factor is a multifunctional cytokine with effects on lipid metabolism, coagulation, insulin resistance, and the function of endothelial cells lining blood vessels. High TNF levels are seen in many inflammatory disease processes, but extreme levels are seen in Crohns Disease.
Crohn's disease, in general, causes inflammation of the digestive system and is classified as one of a group of diseases called inflammatory bowel disease. The disease can affect any area from the mouth to the anus; however, it often affects the lower part of the small intestine called the ileum. Crohn's disease seems to run in some families, particularly of Jewish decent. It can occur in people of all age groups but is most often diagnosed in young adults, around 16-21. Common symptoms are pain in the abdomen and diarrhea. Other symptoms include bleeding from the rectum, weight loss, joint pain, skin problems and fever may also occur. Children with the disease may have growth problems. Other problems can include intestinal blockage and malnutrition. The most severe of cases can lead to death if left untreated, typically from septicemia. Treatment of this horrific disease typically includes medicines, nutrition supplements, surgery or a combination of these options. In the past most medicines for this disease would include immunosuppressant’s and high doses of steroids. Unfortunately, prolonged exposure to these meds can lead to sever side effects themselves. Also people typically build up antibodies to these medicines, and they cease to work. The surgical approach, typically intestinal resection, can be beneficial and life saving in many