Spatial-analysis of flow-induced intermediate filament displacement

Time-lapse optical sectioning microscopy and image restoration was performed on cells expressing green fluorescent protein-vimentin that incorporated into the endogenous intermediate filament (IF) network. Flow onset significantly increased the magnitude and variability in IF movement compared to constitutive motion noted in the absence of shear stress. A newly developed 3-D cross correlation analysis of IF displacement as a function of time and intracellular position demonstrated quantitatively a heterogenous spatial distribution of initial IF movement at the subcellular level. On average, flow induced displacement increased with height in the cell. However, spatial patterns of displacement were highly variable among cells and may be related to factors such as surface topography, network morphology, and cell-cell interactions.