Pseudostratified epithelial tissues are characterized by tightly packed cells with minimal intercellular space. The forces exerted between neighbouring cells play a crucial role on the tissue shape and dynamics. However, the precise effects of these contact forces remain poorly understood and difficult to investigate in vivo.
To address this issue, we developed a particle-based modelling framework that represents each cell geometrically, with cell-cell interactions governed by springs and non-overlapping constraints. The time-discrete dynamics is formulated as a nonconvex constrained minimization problem with an evolving minimizing potential, which leads to a system of differential inclusions as the time-step vanishes.
After validating the model against in vivo data, a combination of in silico and in vivo experiments have shown how nuclear movements influence cell distribution and tissue morphology over time. Additionally, by incorporating cell heterogeneity into the model, we were able to investigate how defects in individual cells may drive cell extrusion - a key step in embryo development and cancer metastasis.
Joint work with Steffen Plunder (Kyoto), Sara Merino-Aceituno (Vienna), Pierre Degond (Toulouse) and Eric Theveneau's lab (CBI, Toulouse)