Host intestinal epithelium and mucus

The host intestinal epithelium and mucus layer represent a complex physiological barrier that separates the internal milieu from the external environment of the gut lumen (Groschwitz & Hogan, 2009, PMID: 19246317). The epithelium is a single layer of specialized cells, including enterocytes, goblet cells, and Paneth cells, which are joined by tight junctions to regulate selective permeability. Overlying this is a protective mucus layer, primarily composed of the gel-forming mucin MUC2, which traps pathogens and provides a niche for the commensal microbiota (Johansson & Hansson, 2016, PMID: 27107040). This system is vital for nutrient absorption and immune tolerance, and its dysfunction is a hallmark of inflammatory bowel diseases (IBD) and various enteric infections (Okumura & Takeda, 2017, PMID: 28123927). While not a single molecular target, many therapies aim to restore its barrier function or modulate its interaction with the microbiome to treat chronic gastrointestinal disorders.

Other names

Intestinal mucosal barrierGut barrierIntestinal epitheliumMucus layerGastrointestinal barrier

Drugs targeting this system typically work by enhancing barrier integrity (e.g., through tight junction modulation), stimulating mucus secretion, or providing a physical protective coating to the epithelial surface to prevent irritation and pathogen attachment.