Bridging microscopic cell dynamics to nematohydrodynamics of cell monolayers

Aleksandra Ardaševa; Romain Mueller; Amin Doostmohammadi

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arXiv · 2204.12994

Bridging microscopic cell dynamics to nematohydrodynamics of cell monolayers

Aleksandra Ardaševa·Romain Mueller·Amin Doostmohammadi

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Abstract

It is increasingly being realized that liquid-crystalline features can play an important role in the properties and dynamics of cell monolayers. Here, we present a cell-based model of cell layers, based on the phase-field formulation, that connects mechanical properties at the single cell level to large-scale nematic and hydrodynamic properties of the tissue. In particular, we present a minimal formulation that reproduces the well-known bend and splay hydrodynamic instabilities of the continuum nemato-hydrodynamic formulation of active matter, together with an analytical description of the instability threshold in terms of activity and elasticity of the cells. Furthermore, we provide a quantitative characterisation and comparison of flows and topological defects for extensile and contractile stress generation mechanisms, and demonstrate activity-induced heterogeneity and spontaneous formation of gaps within a confluent monolayer. Together, these results contribute to bridging the gap between micro-scale cell dynamics and tissue-scale collective cellular organisation.

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Aleksandra Ardaševa, Romain Mueller, Amin Doostmohammadi. 2022-04-27. Bridging microscopic cell dynamics to nematohydrodynamics of cell monolayers. https://arxiv.org/abs/2204.12994

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