Canine endothelial progenitor cell-lined hybrid vascular graft with nonthrombogenic potential.
OBJECTIVE
We sought to fabricate a compliant engineered vascular graft (inner diameter of approximately 4.5 mm and length of 6 cm) lined with endothelial progenitor cells derived from circulating peripheral canine blood and to verify its nonthrombogenicity potential in vivo.


METHODS
Autologous circulating endothelial progenitor cells derived from the peripheral veins of 6 adult mongrel dogs were isolated by using a density gradient method. The cells were proliferated in vitro in EGM-2 culture medium, prelined on the luminal surface of in situ-formed collagen type I meshes as an extracellular matrix, and wrapped with a segmented polyurethane thin film with multiple micropores as a compliant scaffold. After canine carotid arteries were bilaterally implanted with these grafts for 1 and 3 months, microscopic observation, histologic staining, and immunochemical staining were performed to evaluate morphogenesis.


RESULTS
After 33.3 +/- 10.5 days of culture in vitro, 4.2 +/- 1.2 x 10(6) endothelial progenitor cells were obtained. Eleven of the 12 engineered vascular grafts were patent. The grafts possessed smooth, glistening, and ivory-colored luminal surfaces at the predetermined observation period up to 3 months. The intimal layer was covered with confluent, cobblestone-like monolayered cells that were positively stained with factor VIIIB-related antigen. The thickness of the neoarterial walls was approximately 300 microm at 3 months after implantation. A few smooth muscle cells were observed in the medial tissue, and fibroblasts dominated the adventitial tissue.


CONCLUSIONS
Circulating endothelial progenitor cells could be a substitute source of endothelial cells for endothelialization on small-diameter-vessel prostheses to ensure nonthrombogenicity.
He
Hongbing
H
Department of Biomedical Engineering, Graduate School of Medicine, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Shirota
Toshihiko
T
Yasui
Hisataka
H
Matsuda
Takehisa
T
D000199:Actins / Q000378:metabolism; D000818:Animals; D002341:Carotid Artery Thrombosis / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D017536:Carotid Artery, Common / Q000166:cytology / Q000378:metabolism / Q000601:surgery; D002455:Cell Division / Q000502:physiology; D002460:Cell Line; D002470:Cell Survival / Q000502:physiology; D017690:Cell Transplantation; D004285:Dogs; D004730:Endothelium, Vascular / Q000166:cytology*; D005169:Factor VIII / Q000378:metabolism; D005456:Fluorescent Dyes; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006822:Hybrid Cells / Q000166:cytology* / Q000637:transplantation*; D007963:Leukocytes, Mononuclear / Q000166:cytology; D008297:Male; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D008955:Models, Cardiovascular; D009131:Muscle, Smooth, Vascular / Q000098:blood supply / Q000166:cytology; D011183:Postoperative Complications / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D013997:Time Factors; D023822:Tissue Engineering; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism; D014654:Vascular Patency / Q000502:physiology
D000199:Actins; D005456:Fluorescent Dyes; D005169:Factor VIII; D040301:Vascular Endothelial Growth Factor Receptor-2