Endothelial Cell Retention on a Viscoelastic Nanocomposite Vascular Conduit Is Improved by Exposure to Shear Stress Preconditioning Prior to Physiological Flow

In this study, endothelial cell (EC)-seeded nanocomposite grafts were preconditioned with 1-2 dynes/cm(2) in vitro to establish whether low shear stress resulted in improved cell adherence prior to physiological shear stress (15 dynes/cm(2)). Alamar blue cell viability was assessed. Polymerase chain reaction was conducted for glyceraldehyde-3-phosphate dehydrogenase, transforming growth factor beta-1 (TGFbeta-1), vascular endothelial growth factor receptor-1 (VEGFR-1), platelet EC adhesion molecule-1, and vascular endothelial growth factor receptor-2 (VEGFR-2). The Alamar blue results demonstrated improved cellular retention following preconditioning (P < 0.001). VEGFR-2 and TGFbeta-1 expression was up-regulated, and VEGFR-1 down-regulated following preconditioning. This investigation confirms previous findings regarding the potential benefits of preconditioning, and demonstrates that these benefits can be applied to ECs seeded on the nanocomposite employed. It also demonstrates further the suitability and potential of nanocomposite for future use in tissue-engineered cardiovascular devices.