Intestinal epithelial mucus components

The intestinal epithelial mucus components form a complex, multi-layered hydrogel that serves as the primary physical and chemical barrier between the gut lumen and the underlying epithelium (Johansson & Hansson, 2016, Nature Reviews Immunology). This system is predominantly composed of the large, gel-forming glycoprotein Mucin-2 (MUC2), which is secreted by specialized goblet cells and undergoes massive expansion upon release to create a protective matrix (Bansil & Turner, 2018, Advanced Drug Delivery Reviews). In the colon, this barrier consists of a dense inner layer that is virtually sterile and a loose outer layer that provides a habitat for the commensal microbiota (McGuckin et al., 2011, Nature Reviews Microbiology). Beyond structural support, these components integrate antimicrobial peptides and immunoglobulins to regulate host-microbe interactions and prevent the translocation of pathogens. Dysregulation or depletion of these mucus components is a central feature of inflammatory bowel diseases, such as ulcerative colitis, where the loss of barrier integrity leads to chronic inflammation (Kim & Ho, 2010, Current Gastroenterology Reports). Therapeutic targeting of these components involves the use of mucolytics to reduce viscosity in obstructive conditions or the administration of mucosal protectants and secretagogues to reinforce the barrier in inflammatory states.

Other names

Intestinal mucus barrierMucin glycoproteinsGastrointestinal mucus layerColonic mucusMucus gel layer

Cleavage of disulfide bonds in mucin polymers (mucolysis); stimulation of prostaglandin-mediated mucus secretion; physical adherence to the mucosal surface to provide a protective barrier; replenishment of the phospholipid component of the mucus layer.