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bioRxiv · 10.1101/2021.06.09.447726

Contact guidance as a consequence of coupled morphological evolution and motility of adherent cells

Ippolito, A.·DeSimone, A.·Deshpande, V.
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Abstract

Adherent cells seeded on substrates spread and evolve their morphology while simultaneously displaying motility. Phenomena such as contact guidance viz. the alignment of cells on patterned substrates, are strongly linked to the coupling of morphological evolution with motility. Here we employ a recently developed statistical thermodynamics framework for modelling the non-thermal fluctuating response of the cells to probe this coupling. This thermodynamic framework is first extended to predict temporal responses via a Langevin style model. The Langevin model is then shown to not only predict the different experimentally observed temporal scales for morphological observables such as cell area and elongation but also the interplay of morphology with motility that ultimately leads to contact guidance. Author SummaryThe evolution of cellular morphology and organization plays a crucial role in the micro-architecture of tissues and dictates their biological and mechanical functioning. Despite the importance of cellular organization in all facets of tissue biology, the fundamental question of how a cell organizes itself in an anisotropic environment is still poorly understood. We demonstrate, using a Langevin style model, that non-thermal fluctuations fuelled by nutrient exchanges between the cell and its environment are critical in allowing cells to explore their surroundings. The biochemical changes, associated with non-thermal fluctuations, drive cell motility and morphological changes and the interplay between these two emerging dynamics ultimately leads to contact guidance, a critical component for tissue morphogenesis.

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Ippolito, A., DeSimone, A., Deshpande, V.. 2021-06-09. Contact guidance as a consequence of coupled morphological evolution and motility of adherent cells. https://doi.org/10.1101/2021.06.09.447726

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