Microfluidic system for in vitro epithelial folding and calcium waves induction.

Epithelial folding is a fundamental process where initially flat monolayers transform into functional 3D structures. This protocol details fabrication steps for a polycarbonate microfluidic platform which enables triggering epithelial folds that recapitulate stereotypical cell shape changes and folding-associated mechanical stresses. We describe the steps for cell seeding to form a monolayer on the chip, and subsequent approach to trigger calcium waves in the epithelial monolayer through local epithelial deformation. Lastly, we outline quantitative analysis steps of the epithelial response. For complete details on the use and execution of this protocol, please refer to Blonski et al. (2021).