Comprehensive investigation of milk-derived extracellular vesicles on intestinal stem cell-based models.

As bioactive nanoparticles of breast milk, milk-derived extracellular vesicles (MEV) play regulatory roles in animal intestine confirmed by in vivo experiments and intestinal cell line models. However, remarkably little is known about their function on physiologically relevant intestinal models. In this study, we established 3 types of intestinal stem cell (ISC)-based models from the small intestine and colon of piglets, and confirmed their physiological properties in intestinal epithelial cell (IEC) composition, epithelial barrier, and fatty acid uptake. Organoid monolayer and apical-out organoid, but not basal-out organoid, could take up porcine MEV via the apical surface of IEC. Furthermore, MEV promoted the expression of genes related to stemness and differentiation of colon-derived ISC. Mechanistically, the internalization of MEV into IEC was suppressed by endocytosis inhibitors. Overall, this study reveals region-specific differences and uptake mechanism of MEV from the perspective of ISC, and also contributes to in-depth study on intestinal physiology via novel ISC-based models.