Black Dots: Microcontact-Printed, Reference-Free Traction Force Microscopy

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Department of Biomedical Engineering


Measuring the traction forces produced by cells provides insight into their behavior and physiological function. Here, we developed a technique (dubbed ‘black dots’) that microcontact prints a fluorescent micropattern onto a flexible substrate to measure cellular traction forces without constraining cell shape or needing to detach the cells. To demonstrate our technique, we assessed human platelets, which can generate a large range of forces within a population. We find platelets that exert more force have more spread area, are more circular, and have more uniformly distributed F-actin filaments. As a result of the high yield of data obtainable by this technique, we were able to evaluate multivariate mixed effects models with interaction terms and conduct a clustering analysis to identify clusters within our data. These statistical techniques demonstrated a complex relationship between spread area, circularity, F-actin dispersion, and platelet force, including cooperative effects that significantly associate with platelet traction forces.

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The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. © 2021. Publisher’s version of record: https://doi.org/10.1101/2021.08.02.454500

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