Nanoendoscopy-AFM—A Novel Technique for Intracellular Imaging and Measurement of Mechanical Properties

Direct imaging of nanostructures and their dynamics inside living cells has been a great challenge. We have developed nanoendoscopy-AFM (Atomic Force Microscopy), a label-free, non-harmful imaging technique that allows us to see the intracellular structures of a living cell without breaking it apart. A long ultrathin nanoprobe is inserted into living cells to perform 2D and 3D imaging by AFM. We proved that such an imaging method based on ultrathin nanoprobes does not significantly affect cell viability and proliferation. We also investigate the optimal measurement conditions that minimize cell disturbance and avoid inducing significant stress responses.<br/>Besides, measuring the mechanical properties of cells throughout the cell cycle is fundamental to understanding cellular behavior in both physiological and pathological conditions.<br/>Our next aim is to investigate elasticity variations of cellular and nuclear membranes through the cell cycle using the nanoendoscopy-AFM technique. Combining nanoendoscopy-AFM with FUCCI marker-transfected cells allows precise, real-time mechanical measurements and clear visual identification of cell cycle stages. Our preliminary results indicate substantial variations in the stiffness of the cell membrane and nuclear membrane during different stages of the cell cycle. These findings suggest that cell and nuclear membrane stiffness dynamically changes in correlation with the different phases of the cell cycle, providing novel insights into the mechanical properties of cancer cells as they progress through their growth stages.