A Coculture System for Modeling Intestinal Epithelial-Fibroblast Crosstalk.

Epithelial organoid monoculture is a powerful tool to model stem cell dynamics in vitro. However, extensive efforts have recently revealed various niche players and their significant roles in regulating epithelial stem cells. Among these niche components, fibroblasts have been heavily recognized in the field as a critical niche signal secretor. Thus, understanding the roles of fibroblasts in epithelial dynamics has become increasingly relevant and crucial. This propels the development of approaches to coculture epithelial 3D organoids with fibroblasts to model epithelial-fibroblast crosstalk in vitro. Here, we describe a stepwise coculture method to isolate and culture primary intestinal fibroblasts and epithelial organoids together. Aligned with the recent literature, our coculture protocol allows for primary intestinal fibroblast support of epithelial organoid growth.