In Vitro Flow Chamber Design for the Study of Endothelial Cell (Patho)Physiology

In the native vasculature, flowing blood produces a frictional force on vessel walls that affects endothelial cell function and phenotype. In the arterial system, the vasculature's local geometry directly influences variations in flow profiles and shear stress magnitudes. Straight arterial sections with pulsatile shear stress have been shown to promote an athero-protective endothelial phenotype. Conversely, areas with more complex geometry, such as arterial bifurcations and branch points with disturbed flow patterns and lower, oscillatory shear stress, typically lead to endothelial dysfunction and the pathogenesis of cardiovascular diseases. Many studies have investigated the regulation of endothelial responses to various shear stress environments. Importantly, the accurate in vitro simulation of in vivo hemodynamics is critical to the deeper understanding of mechanotransduction through the proper design and use of flow chamber devices. In this review, we describe several flow chamber apparatuses and their fluid mechanics design parameters, including parallel-plate flow chambers, cone-and-plate devices, and microfluidic devices. In addition, chamber-specific design criteria and relevant equations are defined in detail for the accurate simulation of shear stress environments to study endothelial cell responses.