Multi-directional flow chamber: analysis of endothelial cell morphology dependence on differential shear forces

A novel multi-directional flow chamber (MDFC) has been developed as an in vitro tool for testing endothelial cell (EC) responses to complex multidirectional flow patterns. It was developed to model fluid mechanical conditions associated with atherosclerotic prone sites. Experimental studies demonstrated that multi-directional flow (shear stress vector produced by an axial and a rotational component) caused greater morphologic variability than unidirectional flow studies (shear stress vector produced solely. by an axial component). For example, the SI_N for a multi-directional flow study at a position within the MDFC, where the rotational and axial shear stress vectors are parallel and additive, showed significantly more cell elongation (SI_N = 0.83 ± 0.17) than at the ´bottom´ position, where the vectors were in opposite directions (SI_N = 0.95 ± 0.23). The equivalent results in a unidirectional study showed no significant difference at these positions. Therefore, ECs within a single monolayer can respond differentially when exposed to regions with a variable force distribution.