Autologous blood vessels engineered from peripheral blood sample.

OBJECTIVE Although many efforts have been made to generate small-diameter (< or =5mm) vascular grafts by means of tissue engineering, improvement in patency and functionality still remains a great challenge. It is our hypothesis that to achieve long-term functionality and patency, not only the complete lining with endothelial cells but also full biocompatibility is essential. DESIGN The aim was the development of a conduit from a scaffold and endothelial progenitor cells (EPC) separated from peripheral blood of a single donor. MATERIALS AND METHODS EPC and a fibrin preparation were separated from porcine peripheral blood. Fibrin segments were generated seeded with EPC and were perfused in a bioreactor in vitro. RESULTS From 100ml blood 12-15 cm long fibrin tubes were successfully generated lined with endothelial-like cells. Seeded tubes showed a remarkable elasticity and burst strength up to 90 mm mercury. CONCLUSIONS Stable fibrin tubes were successfully generated completely lined with an endothelium-like monolayer from fibrin and EPC, both isolated from the same volume of blood. Although their stability is not those needed for arterial grafting, our results raise the hope, that with distinct improvements in future studies functional autologous vascular grafts could be engineered from the patient's own blood.