• EPITHELIAL CELLS
• GASTROINTESTINAL TRACT
• BACTERIAL INTERACTIONS

The intestinal tract is one of the most complex organs of our body because it has to perform several functions, including digestion and absorption of nutrients. Being exposed to a continuous insult by the local microbiota, the intestinal epithelium is constantly renewed from Lgr5+ stem cell progenitors located in the crypts of Lieberkuhn.1 These progenitors have been recently exploited to regenerate ‘mini-guts’ (organoids) in vitro.2 An appropriate cocktail of small molecules and growth factors has been identified that preserves stemness but also favours the differentiation of enterocytes and Paneth cells thus forming the organotypic structure of a crypt-villous organoid (for a review, see ref. 3).

In this issue of Gut, VanDussen et al 4 show a powerful method of growing human epithelial cells in culture from biopsies of several intestinal segments of either healthy individuals or patients with several pathologies.

The authors established a very simple methodology starting from biopsies collected during routine endoscopy. Crypts were isolated with collagenase digestion and embedded in matrigel with 50% conditioned medium obtained from fibroblasts engineered to secrete Wnt3a, R-spondin and Noggin.5 These three factors were previously shown by the same authors among others to be sufficient to propagate and maintain intestinal epithelial cells in the mouse system.3

In the current manuscript, …