LAUSR

Background & Aims Recent evidence has suggested that the intact intestinal epithelial barrier protects our body from a range of immune-mediated diseases. The epithelial layer has an impressive ability to reconstitute and repair upon damage and this process of repair increasingly is seen as a therapeutic target. In vitro models to study this process in primary intestinal cells are lacking. Methods We established and characterized an in vitro model of intestinal damage and repair by applying γ-radiation on small-intestinal organoids. We then used this model to identify novel regulators of intestinal regeneration. Results We identified hepatocyte nuclear factor 4α (HNF4α) as a pivotal upstream regulator of the intestinal regenerative response. Organoids lacking Hnf4a were not able to propagate in vitro. Importantly, intestinal Hnf4a knock-out mice showed impaired regeneration after whole-body irradiation, confirming intestinal organoids as a valuable alternative to in vivo studies. Conclusions In conclusion, we established and validated an in vitro damage–repair model and identified HNF4α as a crucial regulator of intestinal regeneration. Transcript profiling: GSE141515 and GSE141518.