Microflow Induced Mechanotransduction in HaCaT Cells and its Application in Cell Sheet Engineering

Abstract

The epidermal keratinocytes are known to elicit mechanosensitive response when exposed to fluid shear stress and often undergoes cytoskeletal reorganization and colonization. However, the exact parameters pertaining to the optimal flow rate and time of exposure for mechanotransduction is not well known. Moreover, the cellular signaling pathways involved in flow induced mechanotransduction in HaCat cells is not clear. In this regard, we used bio-microfluidic approach to evaluate to influence of flow induced shear stress on cytoskeletal reorganization of HaCaT cells (human keratinocytes) and to understand the mechanism underlying it. In present study three flow rates were experimented and 0.6 ml/h was found to be optimal. The live cell imaging of HaCaT cells under flow condition showed maximum cell spreading by 6 hours of flow exposure. So study was carried out at 0.6 ml/hour flow for 6 hours. The blocker mediated study showed that majorly actin polymerization and myosin motor protein has a crucial role in shear stress induced mechanotrasduction in HaCaT cells. Variation in lamin expression further confirmed the nuclear mechanotransduction under flow. Enhanced E-Cadherin and decreased N-Cadherin expression implied that shear stress favours epithelial phenotype. The increased expression of ZO-1, a hall mark protein for tight junction confirms that flow mediated shear stress can be used as a mechanoregulator on HaCaT cells to improve cell sheet formation therefore can enhance the permeability barrier and integrity of epidermis