Live Quantitative Characterization for Stem Cell Biomechanics

Abstract In this study, the novel use of high‐resolution force‐curve imaging is demonstrated using Atomic Force Microscopy (AFM) to continuously map topographical and biomechanical changes in individual bone marrow‐derived hMSCs simultaneously with chemical stimulation. The cell's effective stiffness, quantified as Young's modulus, is largely determined by the cytoskeletal structure within the individual cell. Chemical treatments that modulate cytoskeletal dynamics induced measurable changes in the effective stiffness, reflecting changes in cytoskeletal components such as the actin and microtubule networks. Cytochalasin D, blebbistatin, and nocodazole all reduced the effective stiffness of the cells, while colchicine increased the effective stiffness, and this is quantified across whole cells and individual actin fibers over a 200 min period. Performing these measurements continually enabled a temporal analysis of distinct locations and features across the cell with a high degree of spatial confidence.