This Article Full Text Full Text (PDF) All Versions of this Article: biophysj.105.071217v1 89/6/L52    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Saez, A. Articles by Ladoux, B. Search for Related Content PubMed PubMed Citation Articles by Saez, A. Articles by Ladoux, B.

Is the Mechanical Activity of Epithelial Cells Controlled by Deformations or Forces?

Alexandre Saez ^*, Axel Buguin , Pascal Silberzan  and Benoît Ladoux ^*

^* Matière et Systèmes Complexes, CNRS UMR 7057/Université Paris 7, Tour 33-34, 2 place Jussieu 75005 Paris, France; Physico-Chimie Curie, CNRS UMR 168, 26 rue d'Ulm, 75248 Paris cedex 05, France

Correspondence: Address reprint requests and inquiries to Benoit Ladoux, Tel.: +33-1-44-27-61-10; Fax: 33-1-44-27-43-35; E-mail: benoit.ladoux{at}paris7.jussieu.fr.

The traction forces developed by cells depend strongly on the substrate rigidity. In this letter, we characterize quantitatively this effect on MDCK epithelial cells by using a microfabricated force sensor consisting in a high-density array of soft pillars whose stiffness can be tailored by changing their height and radius to obtain a rigidity range from 2 nN/µm up to 130 nN/µm. We find that the forces exerted by the cells are proportional to the spring constant of the pillars meaning that, on average, the cells deform the pillars by the same amount whatever their rigidity. The relevant parameter may thus be a deformation rather than a force. These dynamic observations are correlated with the reinforcement of focal adhesions that increases with the substrate rigidity.

This article has been cited by other articles:

				A. Nicolas, A. Besser, and S. A. Safran Dynamics of Cellular Focal Adhesions on Deformable Substrates: Consequences for Cell Force Microscopy Biophys. J., July 15, 2008; 95(2): 527 - 539. [Abstract] [Full Text] [PDF]

				D. Icard-Arcizet, O. Cardoso, A. Richert, and S. Henon Cell Stiffening in Response to External Stress is Correlated to Actin Recruitment Biophys. J., April 1, 2008; 94(7): 2906 - 2913. [Abstract] [Full Text] [PDF]

				R. De, A. Zemel, and S. A. Safran Do Cells Sense Stress or Strain? Measurement of Cellular Orientation Can Provide a Clue Biophys. J., March 1, 2008; 94(5): L29 - L31. [Abstract] [Full Text] [PDF]

				A. Kajzar, C. M. Cesa, N. Kirchgessner, B. Hoffmann, and R. Merkel Toward Physiological Conditions for Cell Analyses: Forces of Heart Muscle Cells Suspended Between Elastic Micropillars Biophys. J., March 1, 2008; 94(5): 1854 - 1866. [Abstract] [Full Text] [PDF]

				J. Solon, I. Levental, K. Sengupta, P. C. Georges, and P. A. Janmey Fibroblast Adaptation and Stiffness Matching to Soft Elastic Substrates Biophys. J., December 15, 2007; 93(12): 4453 - 4461. [Abstract] [Full Text] [PDF]

				A. Saez, M. Ghibaudo, A. Buguin, P. Silberzan, and B. Ladoux Rigidity-driven growth and migration of epithelial cells on microstructured anisotropic substrates PNAS, May 15, 2007; 104(20): 8281 - 8286. [Abstract] [Full Text] [PDF]