Emergence of epithelial cell density waves

TL;DR

This paper explains how epithelial cell monolayers generate traveling density waves through a hydrodynamic model, revealing a Hopf bifurcation as the mechanism behind wave emergence.

Contribution

It introduces a hydrodynamic framework modeling epithelial monolayers as active, polar, and compressible materials, identifying the bifurcation responsible for density wave propagation.

Findings

Density waves are explained by a Hopf bifurcation.

The model predicts wave propagation above certain active coupling thresholds.

Epithelial monolayers behave as active, polar, compressible materials.

Abstract

Epithelial cell monolayers exhibit traveling mechanical waves. We rationalize this observation thanks to a hydrodynamic description of the monolayer as a compressible, active and polar material. We show that propagating waves of the cell density, polarity, velocity and stress fields may be due to a Hopf bifurcation occurring above threshold values of active coupling coefficients.