Mucosal barrier

The mucosal barrier, often termed mucosal protection, comprises the dynamic structural and functional elements lining the gastrointestinal tract, respiratory system, and urogenital tract, serving as the body's primary defense against pathogens, irritants, and harmful substances. It integrates a physical mucus gel layer rich in mucins (e.g., MUC2, transmembrane mucins like MUC1), epithelial tight junctions, and submucosal immune components such as MALT, including dendritic cells, Tregs, plasma cells secreting IgA, and innate lymphoid cells, to exclude invaders while tolerating commensals and food antigens.[1][2][3][5] In disease, disruptions lead to conditions like inflammatory bowel disease, peptic ulcers, and infections, where impaired barrier integrity heightens susceptibility to inflammation and microbial penetration.[1][3][7] Drugs targeting mucosal protection, such as prostaglandins and sucralfate, bolster mucus secretion, epithelial repair, and microvascular stability to prevent injury from gastric acid or pepsin, though challenges include maintaining homeostasis without altering microbiota.[2][6][7][12] Overall, this system ensures selective permeability for nutrient absorption while mounting rapid innate and adaptive responses.[3][4]

Other names

mucosal protection mechanismsmucosal barrier functionmucus immune system

Enhance mucus production, strengthen epithelial tight junctions, preserve microvascular integrity, promote rapid cell restitution, and neutralize gastric acid and pepsin.