Quasi-realistic modelling of expanding epithelial cell monolayer

An expanding epithelial cell monolayer on a 2-dimensional substrate exhibits intriguing mechanical patterns. The distribution of mechanical quantities over space and time thereby hints a picture integrating cell-cell and cell-substrate interactions. We propose a quasi-realistic model for this phenomenon. Specifically, we model cells as active constituents that would maintain force-equilibrium at the end of each motile step. The model cells contract with a tension-dependent speed, and protrude after reaching the maximum allowed contraction. Cell-substrate and cell-cell elastic adhesion bonds form, break and relocate stochastically, so as to capture contact inhibition as well as other effects. We bring forward this bottom-up approach to reveal the essential mechanisms leading to the macroscopic patterns.