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bioRxiv · 10.1101/2025.05.27.656457

Chemotaxis of branched cells in complex environments

Liu, J.·Ron, J. E.·Rinaldi, G.·Williantarra, I.·Georgantzoglou, A.·de Vries, I.·Sixt, M.·Sarris, M.·Gov, N.
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Abstract

Cell migration in vivo is often guided by chemical signals. Such chemotaxis, such as performed by immune cells migrating to a wound site, is complicated by the complex geometry inside living tissues. In this study, we extend our theoretical model of branched-cell migration on a network by introducing chemokine sources to explore the cellular response. The model predicts a speed-accuracy tradeoff, whereby slow cells are significantly more accurate and able to follow efficiently a weak chemoattractant signal. We then compare the models predictions with experimental observations of neutrophils migrating to the site of laser-inflicted wound in a zebrafish larva fin, and migrating in-vitro inside a regular lattice of pillars. We find that the model captures the details of the sub-cellular response to the chemokine gradient, as well as the large-scale migration response. This comparison suggests that the neutrophils behave as fast cells, compromising their chemotaxis accuracy, which explains the functionality of these immune cells.

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Liu, J., Ron, J. E., Rinaldi, G., Williantarra, I., Georgantzoglou, A., de Vries, I., Sixt, M., Sarris, M., Gov, N.. 2025-05-29. Chemotaxis of branched cells in complex environments. https://doi.org/10.1101/2025.05.27.656457

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