Endothelial cell seeding onto the extracellular matrix of fibroblasts for the development of a small diameter polyurethane vessel.

: A variety of experiments of endothelial cell seeding on artificial vessels have been performed. To improve endothelialization, one or two extracellular matrix components have been used as an underlying matrix. Although these methods have succeeded in in vitro experiments, they have not performed well in vivo. In this study, the authors used the whole extracellular matrix (ECM) excreted from fibroblasts as an underlying matrix. Fetal human fibroblasts were cultured on a polyurethane (PU) sheet. After confluence was attained, the cytoskeleton and the nuclei of the fibroblasts were destroyed using Triton-X, mitomycin, and irradiation. Omental microvascular endothelial cells from adult humans were seeded on various supports. After 12 days in culture, the cells were counted. The authors found that the ECM treated by irradiation had the highest cell number. In addition, the cells on this support exhibited the best morphologic appearance. Finally, the authors performed preliminary animal experiments. The PU vessels (inner diameter: 1.5 mm) treated with ECM were implanted in the arteries of rats. After the vessels had been implanted for 5 weeks, the authors found that the surface of the PU vessels were completely covered with endothelial cells. On the basis of these results, the authors conclude that the whole ECM makes a better underlying substrate for the endothelialization of small diameter artificial vessels.