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This work presents a new numerical method for processing atomic force microscopy (AFM) data to determine the elasticity of cultured adherent biological cells. Raw AFM force-indentation data is commonly interpreted using the Hertz and Sneddon contact mechanics models to fit a Young’s modulus or apparent cell elasticity. This apparent cell elasticity is highly dependent on the method used to identify the first point of contact between the AFM probe and the cell surface.

Mechanical behavior of cells plays a crucial role in response to external stimuli and environment. It is very important to elucidate the mechanisms of cellular activities like spreading and alignment as it would shed light on further biological concepts. A multi-scale computational approach is adopted by modeling the cytoskeleton of cell as a tensegrity structure. The model is based on the complementary force balance between the tension and compression elements, resembling the internal structure of cell cytoskeleton composed of microtubules and actin filaments.

Myosin-generated stresses are responsible for non-equilibrium mechanical behavior of synthesized cytoskeletal networks in vitro. In particular, it is found that myosin stresses can modify the network elasticity. For living cells, it has been suggested that internally generated stress might help cells sense and mimic the stiffness of their environments. However, cellular mechanical responses to intracellular stress are not well understood.