Dynamic response of endothelial cells to flow as measured by total internal reflectance fluorescence microscopy

To study the effect of luminal fluid stress on the abluminal cell surface and its adhesion sites, called focal contacts, total internal fluorescence reflectance microscopy is developed for measuring the dynamic response of endothelial cell focal contacts to flow in vitro. This method is used to illuminate the lower cell membrane so that focal contact movement can be followed over time. Based on the results, it is indicated that abluminal cell contour modulation occurs at a moderate level under static and low shear conditions, increasing substantially at higher shear rates. Moreover, at early flow time, the cell contour is moving away from the surface and focal contact sites are decreasing in response to the fluid stress.