Finite Element Modeling of Cell Traction

Cell traction forces generated via the actomyosin interaction within the cell play a critical role in many biological and pathological processes including angiogenesis, wound healing, embryogenesis, metastasis, tumor invasion, and inflammation. In the case of tumor invasion, several studies have reported a correlation between cellular traction and invasion potential; however, these results are inconsistent. In their study, Kraning-Rush et al. reported a positive correlation between cellular traction as measured by total force and metastasis potential. On the other hand, Koch et al. reported a negative correlation between tumor cell invasion and cellular traction as measured by strain energy. We hypothesized that this ambiguity could be a result of overlooked effects of other parameters on measured cellular traction. Using finite element modeling of cell traction, we explored the effect of multiple morphological and mechanical parameters on the measured cellular traction using both strain energy and cellular traction forces as the model outputs. Our results demonstrate a clear dependence of strain energy on substrate stiffness, cell polarity, and contact area, whereas, total force was independent of any of the tested parameters. In addition, our results predict the ability of cells to alter the apparent stiffness of their environment by changing their focal adhesion size.