Fluid Shear Stress Promotes Mouse Embryonic Stem Cell Pluripotency via E-cadherin Mechanotransduction
Abstract
Embryonic stem cells (ESCs) are capable of self-renewal and differentiation into any cell type; this is a powerful tool in generating different cell lineages for regenerative medicine. Stirred suspension bioreactors have been developed as a way to culture ESCs quickly and with minimal labour. Cells are stirred at 100 RPM, which has a maximum tip shear stress of 6 dyne/cm2. We have discovered that cells grown under these conditions maintain pluripotency even in the absence of leukemia inhibitory factor (LIF), an obligate pluripotency maintenance factor. Prior studies have shown that cells can sense physical signals such as shear stress in their environment and modulate a biochemical response through mechanotransduction. In this thesis, I show a link between mechanotransduction and the maintenance of pluripotency. In response to shear stress, β-catenin, a member of the wnt pathway is translocated to the nucleus. Inhibition of β-catenin in the bioreactor results in a decrease in pluripotency gene expression. The disruption of vinculin, a protein recruited to the periphery of the cell in response to shear stress, also leads to a reduction in bioreactor induced pluripotency. Direct manipulation of cells bound to Ecadherin peptides with shear stress generates nuclear β-catenin translocation as well as accumulation of vinculin on the periphery of the cell. These results indicate that shear stress induces bioreactor maintained pluripotency, a phenomenon we have named mechanopluripotency.
Description
Keywords
Biology--Cell, Biology--Molecular
Citation
Day, B. (2017). Fluid Shear Stress Promotes Mouse Embryonic Stem Cell Pluripotency via E-cadherin Mechanotransduction (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/26198