Intestinal and mucosal immune system (MIS/GALT)

The intestinal and mucosal immune system is a specialized branch of the immune system that protects the body's internal surfaces, particularly the gastrointestinal tract, which is the largest area of exposure to external antigens (Mowat & Agace, 2014, Science). It consists of organized lymphoid tissues like Gut-associated lymphoid tissue (GALT) and diffuse effector cells that maintain a balance between tolerance to food and commensal bacteria and defense against pathogens (StatPearls, 2023). Dysregulation of these mucosal immune responses is central to the pathogenesis of inflammatory bowel diseases (IBD), such as Crohn's disease and ulcerative colitis (Neurath, 2014, Nature Reviews Immunology). While the system itself is not a single molecular target, it contains numerous specific targets for therapeutic intervention, including integrins like alpha-4 beta-7 and cytokines like TNF-alpha and IL-23 (Danese et al., 2015, Gut). Drugs such as vedolizumab and ustekinumab are designed to target these specific components to restore intestinal homeostasis and promote mucosal healing (Sandborn et al., 2013, NEJM).

Other names

Mucosal immune systemGut-associated lymphoid tissueGALTMucosa-associated lymphoid tissueMALT

Therapeutic strategies involve the modulation of leukocyte trafficking to mucosal sites, neutralization of pro-inflammatory cytokines (e.g., TNF, IL-23), and sequestration of lymphocytes in lymph nodes via S1P receptor modulation.