Measurement of Cell-Generated Traction Stresses Using the Elastic Substrate Method

William Marganski, Boston University

The forces exerted by an adherent cell on the underlying substratum, the so-called cellular tractions, are important because of their potential involvement in cell motion, tissue morphogenesis, and wound healing. Elastic substrate methods are the principal means for investigating the cellular tractions. The essential idea is to culture a cell on a flexible substratum of known mechanical properties and to use the way this material deforms as the basis for drawing conclusions. The theory for the deformation of elastic substrata is well understood and the methodology to interpret such deformations in terms of cellular forces has been described previously (Dembo and Wang, 1999). Here we present the recent advances in measuring the substrate deformations using a correlation-based optical flow approach. Additionally, we discuss how the error in the final estimate of the traction field can be quantified and how it depends on the detailed nature of the underlying data. Lastly, we apply the elastic substrate method to study the contractility of the cardiac fibroblast and investigate its possible role in promoting cardiac dysfunction during hypertension.

Dembo, M. and Y.-L.Wang. 1999. Stresses at the Cell-to-Substrate Interface During Locomotion of Fibroblasts. Biophysical Journal. 76:2307-2316.

Abstract Author(s): William A. Marganski and Micah Dembo