Intestinal epithelial cell surface and mucosal glycoproteins

Intestinal epithelial cell surface and mucosal glycoproteins constitute a complex structural and functional barrier in the gastrointestinal tract, primarily composed of secreted and membrane-bound mucins (Johansson & Hansson, 2016, Nature Reviews Immunology). The secreted layer, dominated by MUC2, forms a physical gel that traps pathogens and limits their contact with the epithelium, while membrane-bound mucins like MUC1, MUC3, and MUC17 form the glycocalyx, which facilitates cell signaling and provides a final defensive layer (Bansil & Turner, 2018, Advanced Drug Delivery Reviews). These glycoproteins are essential for lubricating the intestinal lumen and protecting the underlying epithelium from mechanical damage and enzymatic digestion (Corfield, 2015, BBA-General Subjects). They also play a critical role in regulating the interaction between the host and the gut microbiota, providing a niche for commensal bacteria. Dysregulation of these glycoproteins is a hallmark of various pathologies, including inflammatory bowel disease (IBD), where the mucus layer is thinned, and colorectal cancer, where altered glycosylation promotes tumor survival. Therapeutically, these molecules are targeted by mucolytics like N-acetylcysteine to clear obstructive mucus or by mucoadhesive polymers designed to prolong drug residence time (Khutoryanskiy, 2011, Chemical Society Reviews). Additionally, agents like rebamipide are used to enhance the production of these glycoproteins to treat mucosal injury and inflammation (NCBI PMC4110828).

Other names

Intestinal glycocalyxMucinsGastrointestinal mucus layerBrush border glycoproteinsIntestinal mucosal barrierMucin-type glycoproteins

Mucolysis via disulfide bond reduction; Mucoadhesion via non-covalent interactions; Induction of mucin secretion; Physical barrier enhancement