Immune-Mediated Disorders

Immune-mediated disorders (IMDs) consist of a wide spectrum of gastrointestinal and extraintestinal disorders. Deregulation of immune response and chronic inflammation have a crucial role in the development of infectious, inflammatory, and autoimmune diseases which affect abdominal organs as well. The etiology of these diseases is multifactorial including environmental factors, dietary habits, and pathogens in genetically susceptible patients. It causes injuries to the tissue and organs in the gastrointestinal tract, affected due to the excessive and uncontrolled inflammation. Over the past decade, our knowledge of underlying molecular and pathophysiological mechanisms that lead to IMDs has greatly advanced. It is now understood that interruption in the regulation of innate and adaptive immunity caused by environmental triggers in genetically predisposed individuals can set off an inappropriate or excessive immune response that can lead to the destruction of tissue or organs. Overall in IMDs, a TH1 immune response and also a reduction of the differentiation to the TH2 response are dominant. Once an antigen in IMDs initiates the inflammatory response, higher production of pro-inflammatory cytokines is observed such as TNF-α, IL-1, and IL-6, and the reduction of other cytokines such as IL-10 and IL-4. In the past three decades, remarkable advances have been made in the ability to target specific components of the immune and inflammatory response providing superior treatments for IMDs.