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bioRxiv · 10.1101/2022.11.16.516758

Dynamic traction force measurements of migrating immune cells in 3D matrices

Boehringer, D.·Condor, M.·Bischof, L.·Czerwinski, T.·Bauer, A.·Voskens, C.·Budday, S.·Mark, C.·Fabry, B.·Gerum, R.
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Abstract

Immune cells such as natural killer (NK) cells migrate with high speeds of several {micro}m/min through dense tissue, but the traction forces are unknown. We present a method to measure dynamic traction forces of fast migrating cells in non-linear biopolymer matrices. The method accounts for the mechanical non-linearity of the 3D tissue matrix and can be applied to time series of confocal or bright-field image stacks. The method is highly sensitive over a large range of forces and object sizes, from [~]1 nN for axon growth cones up to [~]10 {micro}N for mouse intestinal organoids. We find that NK cells display bursts of large traction forces that increase with matrix stiffness and facilitate migration through tight constrictions.

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Boehringer, D., Condor, M., Bischof, L., Czerwinski, T., Bauer, A., Voskens, C., Budday, S., Mark, C., Fabry, B., Gerum, R.. 2022-11-17. Dynamic traction force measurements of migrating immune cells in 3D matrices. https://doi.org/10.1101/2022.11.16.516758

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