title: Mapping intracellular mechanics on micropatterned substrates.
abstract: The mechanical properties of cells impact on their architecture, their migration, intracellular trafficking, and many other cellular functions and have been shown to be modified during cancer progression. We have developed an approach to map the intracellular mechanical properties of living cells by combining micropatterning and optical tweezers-based active microrheology. We optically trap micrometer-sized beads internalized in cells plated on crossbow-shaped adhesive micropatterns and track their displacement following a step displacement of the cell. The local intracellular complex shear modulus is measured from the relaxation of the bead position assuming that the intracellular microenvironment of the bead obeys power-law rheology. We also analyze the data with a standard viscoelastic model and compare with the power-law approach. We show that the shear modulus decreases from the cell center to the periphery and from the cell rear to the front along the polarity axis of the micropattern. We use a variety of inhibitors to quantify the spatial contribution of the cytoskeleton, intracellular membranes, and ATP-dependent active forces to intracellular mechanics and apply our technique to differentiate normal and cancer cells.
authors: Institut Curie, Paris Sciences et Lettres Research University, CNRS, UMR 144, F-75005 Paris, France.|Sorbonne Universités, Université Pierre et Marie Curie, University Paris 06, CNRS, UMR 144, F-75005 Paris, France.|Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA 19104.
authors: Kalpana
authors: K
authors: Mandal
authors: Laboratoire Matière et Systèmes Complexes, CNRS-Université Paris Diderot, Sorbonne Paris Cité, 75205 Paris Cedex 13, France.
authors: Atef
authors: A
authors: Asnacios
authors: Institut Curie, Paris Sciences et Lettres Research University, CNRS, UMR 144, F-75005 Paris, France.|Sorbonne Universités, Université Pierre et Marie Curie, University Paris 06, CNRS, UMR 144, F-75005 Paris, France.
authors: Bruno
authors: B
authors: Goud
authors: Institut Curie, Paris Sciences et Lettres Research University, CNRS, UMR 144, F-75005 Paris, France; jean-baptiste.manneville@curie.fr.|Sorbonne Universités, Université Pierre et Marie Curie, University Paris 06, CNRS, UMR 144, F-75005 Paris, France.
authors: Jean-Baptiste
authors: JB
authors: Manneville
mesh_terms: D000255:Adenosine Triphosphate / Q000502:physiology; D002460:Cell Line; D045744:Cell Line, Tumor; D002468:Cell Physiological Phenomena; D003599:Cytoskeleton / Q000502:physiology; D004548:Elasticity; D006801:Humans; D007425:Intracellular Membranes / Q000502:physiology; D009369:Neoplasms / Q000503:physiopathology*; D052898:Optical Tweezers; D012212:Rheology; D014783:Viscosity
chemical_list: D000255:Adenosine Triphosphate
keywords: cancer; cytoskeleton; microrheology; optical tweezers; viscoelasticity