IBD/Crohn’s Disease and Ulcerative Colitis
Inflammatory bowel disease (IBD) refers to two diseases – Crohn’s disease and ulcerative colitis – both characterized by inflammation of the gastrointestinal tract. Crohn’s disease can cause inflammation in any part of the digestive tract but often affects the tail end of the small intestine. Ulcerative colitis is inflammation of the large intestine. Both Crohn’s disease and ulcerative colitis are chronic and recurring inflammatory conditions. Researchers believe that these conditions occur when the body’s inflammatory cells become over-reactive and mount a destructive inflammatory response. Current treatments for IBD include immunosuppressive therapies, such as TNF- α inhibitors, antibiotics and when all else fails, surgery.
Th17 Driven Diseases
One of the most intriguing areas of current research in immunology involves a newly discovered type of helper T cells known as Th17 cells. While Th17 cells most likely play a role in the protection against extracellular pathogens, there is a large amount of preclinical and clinical data that implicate these cells, as well as IL-17, in the development of a large number of autoimmune diseases, including psoriasis, rheumatoid arthritis, asthma, and multiple sclerosis. Activated Th17 cells isolated from chronically inflamed human tissues produce high levels of TNF- α and other cytokines. A hallmark of Th17 cells is that they express high levels of the chemokine receptor known as CCR6, which is not found on Th1 and Th2 cells. High levels of the CCR6 chemokine ligand, CCL20, have been found in psoriatic skin, in rheumatoid arthritis joint biopsies, and in asthmatic lungs.