Substrate stiffness regulates the proliferation, migration, and differentiation of epidermal cells.

The aim of this study was to investigate the role of substrate stiffness on the proliferation, migration, and differentiation of epidermal cells. To investigate the effects of substrate stiffness on wound healing, epidermal cells were chosen and inoculated on silicone substrate with different values of Young's modulus of elasticity. The cell growth curve, MTT method, and cell cycle detection were used to investigate proliferation, and the scratch test was used to investigate cell migration. Fluorescence flow cytometry was used to study epidermal cell differentiation. The proliferation and migration of epidermal cells favoured stiffer surfaces. A highly stiff surface stimulated epidermal cell proliferation and migration and increased re-epithelialisation, but inhibited differentiation. The candidate pathways mediating epidermal cell proliferation and migration are linked to cell anchoring to substrates by integrin-mediated focal adhesion.

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