Atomic Force Microscopy indentation of living cells

Atomic Force Microscopy (AFM) indentation on living cells in physiological medium is a well established technique used for investigation of the cell mechanical properties at nanoscale. However, interpretation of the experimental data obtained in such experiments is rarely a trivial task. This is happening because living cells have a complex response to the applied mechanical stress, response that is governed by the plastic, elastic, viscosity and adhesion properties of the cells. This chapter presents recent results obtained in AFM indentation of living eukaryotic cells. Contributions of elastic and adhesion properties of the cells to the indentation loading and unloading force curves are discussed. A special attention is devoted to the role of adhesion force in interpretation of force curve data. It is shown that the use of an appropriate indentation model may provide information on the cell cytoskeleton elasticity and the work of adhesion of the cell membrane to the surface of the AFM probes.