Human Saphenous Vein Endothelial Cell Isolation and Exposure to Controlled Levels of Shear Stress and Stretch

Coronary artery bypass graft (CABG) surgery is a procedure to revascularize ischemic myocardium. Saphenous vein remains used as a CABG conduit despite the reduced long-term patency compared to arterial conduits. The abrupt increase of hemodynamic stress associated with the graft arterialization results in vascular damage, especially the endothelium, that may influence the low patency of the saphenous vein graft (SVG). Here, we describe the isolation, characterization, and expansion of human saphenous vein endothelial cells (hSVECs). Cells isolated by collagenase digestion display the typical cobblestone morphology and express endothelial cell markers CD31 and VE-cadherin. To assess the mechanical stress influence, protocols were used in this study to investigate the two main physical stimuli, shear stress and stretch, on arterialized SVGs. hSVECs are cultured in a parallel plate flow chamber to produce shear stress, showing alignment in the direction of the flow and increased expression of KLF2, KLF4, and NOS3. hSVECs can also be cultured in a silicon membrane that allows controlled cellular stretch mimicking venous (low) and arterial (high) stretch. Endothelial cells' F-actin pattern and nitric oxide (NO) secretion are modulated accordingly by the arterial stretch. In summary, we present a detailed method to isolate hSVECs to study the influence of hemodynamic mechanical stress on an endothelial phenotype.