Quantifying cellular traction forces in three dimensions
Abstract
Cells engage in mechanical force exchange with their extracellular environment through tension generated by the cytoskeleton. A method combining laser scanning confocal microscopy (LSCM) and digital volume correlation (DVC) enables tracking and quantification of cell-mediated deformation of the extracellular matrix in all three spatial dimensions. Time-lapse confocal imaging of migrating 3T3 fibroblasts on fibronectin (FN)-modified polyacrylamide gels of varying thickness reveals significant in-plane (x, y) and normal (z) displacements, and illustrates the extent to which cells, even in nominally two-dimensional (2-D) environments, explore their surroundings in all three dimensions. The magnitudes of the measured displacements are independent of the elastic moduli of the gels. Analysis of the normal displacement profiles suggests that normal forces play important roles even in 2-D cell migration.
Additional Information
© 2009 by the National Academy of Sciences. Edited by Steven G. Boxer, Stanford University, Stanford, CA, and approved November 2, 2009 (received for review April 27, 2009). Published online before print December 15, 2009. Author contributions: S.A.M., C.F., D.A.T., and G.R. designed research; S.A.M. and C.F. performed research; S.A.M. and C.F. contributed new reagents/analytic tools; S.A.M., C.F., D.A.T., and G.R. analyzed data; and S.A.M., C.F., D.A.T., and G.R. wrote the paper. We thank Petros Arakelian for help in constructing the experimental setup and Professor Scott Fraser's laboratory for providing the GFP-transfected fibroblasts. This work was funded by a grant from the National Science Foundation through the Center for the Science and Engineering of Materials at the California Institute of Technology. S.A.M. acknowledges support from the National Institutes of Health through a predoctoral National Research Service Award fellowship.Attached Files
Published - Maskarinec2009p6814P_Natl_Acad_Sci_Usa.pdf
Supplemental Material - 0904565106SI.pdf
Supplemental Material - SM1.avi
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- PMCID
- PMC2799761
- Eprint ID
- 17291
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- CaltechAUTHORS:20100122-134235353
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- NIH
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2010-01-29Created from EPrint's datestamp field
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2021-11-08Created from EPrint's last_modified field
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