Tissue Engineering of Vascular Graft

Cardiovascular disease is becoming the leading cause of death in developed countries in recent decades. Coronary artery bypass surgery (for small diameter < 4 mm graft) is performed annually in the world to cure this disease. Autogenous saphenous veins, synthetic grafts, and/or acellular human umbilical veins are presently used as vascular replacement in surgery. However, limited availability of the graft and the constrained conduit diameter still troubled clinical doctors. In addition, the recurrences of obstructed blood vessels, thrombosis, and elicitation of serious immune response challenged researchers as well. This objective of this study is to fabricate an adequate blood vessel substitute with suitable mechanical property and biocompatibility for clinical applications. In this study, we are going to prepare blood vessel based on type I collagen membrane, which could offer temporary supports for tissue organization, repair, and remodeling. Endothelial cells and smooth muscle cells harvested from endocardium, bladder, and blood vessel, respectively, will be seeded on a performed scaffold for cell proliferation and differentiation. In the animal study, we found that endothelial cells could survive and smoothly cover the whole surface are of the scaffold. Smooth muscle cells could proliferate and show positive reaction by vWF immunostain. This study was designed to mimic the structure & morphology of the natural artery. We expect that the cultured construct will eventually develop into a physiologically functional blood vessel and can provide an alternate source of vascular grafts for patients who lack sufficient conduit in the future.