Measurement of surface topography of endothelial cell and wall shear stress distribution on the cell

Responses of endothelial cells to shear stress due to blood flow are basically heterogeneous. One of the reasons of the heterogeneity may be variation of the shear stress at individual cell level. In this study, we presented a method of three-dimensional cell shape measurement by confocal laser scanning microscōpy, and determination of shear stress distribution on the surface of the cell by particle tracking velocimetry with a scale-up model. Thereby, shear stress distribution on the surface of statically cultured cells and flow-exposed cells was determined. From the results of two examples, it has been shown that the shear stress distribution on a cell had close correlation not only with the surface geometry of the cell but also with that of surrounding cells, and varied from cell to cell. The subcelluar distribution of the shear stress may provide important information to clarify the mechanisms of the mechanotransduction of endothelial cells.