Extracellular vesicles in inflammatory bowel disease: from immune regulation and barrier repair to precise transformation.

Extracellular vesicles (EVs) have been shown to be key regulators of intestinal homeostasis and inflammatory responses, offering new insights into the pathogenesis of inflammatory bowel disease (IBD) and the development of targeted therapeutic strategies. EVs in the intestine can be secreted by intestinal epithelial cells (IECs), mesenchymal stem cells (MSCs), immune cell subsets, the gut microbiota, and even dietary sources. Its vesicle internal load contains a variety of biologically active molecules, including proteins, miRNAs, and microbial signals, which mediate immune regulation, intestinal barrier repair, and microbiota regulation. Mechanistically, EVs shape intestinal immune homeostasis by regulating T cell differentiation, macrophage polarization, inflammasome activation and epithelial regeneration, while promoting angiogenesis and fibrosis reversal, and mediating interaction between the host and the microbiota. In clinical settings, EVs are stable and easily accessible biomarkers in blood, feces, and intestinal lavage fluid, which can reflect disease activity, microbiota disorders, and treatment responses. The therapeutic value of EVs lies in their cell targeting ability, stability and drug-loading potential, enabling them to be transformed from biological entities into medical tools. Although it still faces challenges in large-scale production, biodistribution and regulatory standardization, it has broad prospects in promoting the accurate diagnosis and treatment of IBD.