Cell-Substrate Interactions: Finite Element Modeling of Cell Mechanical Responses to Micropillar Substrates

The cell-substrate interaction is a critical aspect of mechanobiology. The geometry of the substrate significantly influences this interaction and can affect cell behaviors. In the current study, a finite element model was developed to investigate the interaction between cells and a Polydimethylsiloxane (PDMS) substrate, both with and without micropillars. Also, the effects of substrate thickness and three key micropillar parameters (height, diameter, and center-tocenter spacing) were explored. The findings revealed that under tensile loading ($10 \%$ strain), increasing the height, diameter, and center-to-center spacing of micropillars significantly affects stress in cell-substrate interface for cells on the PDMS substrate. However, the results indicated that in a flat substrate without any micropillar, variations in the substrate thickness have negligible effects on stress values. Based on the results, it can be concluded that mechanical behavior of cells is notably influenced by geometrical parameters, particularly when these parameters are related to alterations in micropillar geometry rather than changes on a flat surface.