UC Santa Barbara

This work is a culmination of our efforts in understanding cellular mechanics at the scale of single cells and small tissues. We developed methods to quantify cell-generated traction forces using cell-sized, synthetic, functionalized hydrogel microspheres. Cell-sized solid microspheres can provide information regarding cell-generated normal and shear forces while allowing natural cell-cell interactions and facilitating a convex cell-hydrogel interface. Therefore, they are a better mimic than the current methods for understanding the natural cell-cell interactions in a physiologically relevant geometry. In the analysis of the microsphere deformations, we use a boundary spectral method based on spherical harmonics decomposition of the traction field on the spherical gel surface. Using the techniques developed here, we measure the boundary traction profiles that mammalian cells exert on the synthetic microspherical hydrogel bodies. In this report, we briefly review the state of the art in cellular force quantification methods and discuss the contributions of our work to the field and its strengths as well as its limitations.