Integration of total internal reflection and atomic force microscopy (TIRFM-AFM) to study stress transduction mechanisms in endothelial cells

The purpose of this study was to integrate atomic force microscopy (AFM) and total internal reflection fluorescence microscopy (TIRFM) data to determine the effect of localized force application over the cell surface on the cell's focal contacts size and position. TIRFM gives detailed information on the cell-substrate contact regions and AFM is a tool for elasticity measurements, force application, and topographic surface mapping of the cell. Elasticity measurements indicated that the nuclear region was stiffer than the cell body. Following application of nanonewtons force above the nucleus, the cell-substrate contacts rearranged to offset the force. It is evident that the stress applied to the upper surface of the cell is transmitted to the cell-substrate contact region.