In vivo behavior of decellularized vein allograft.
BACKGROUND
We are investigating decellularized vein allograft as a scaffold to engineer a non-synthetic, small-diameter vascular graft. This study examines the in vivo behavior of this scaffolding after implantation into the arterial circulation.


METHODS
Canine animals underwent bilateral carotid interposition grafting using jugular vein implanted as either: 1) fresh autograft, 2) fresh allograft, or 3) decellularized allograft. Decellularization was achieved using sodium dodecyl sulfate. Grafts were examined with duplex ultrasound biweekly to determine luminal diameter, thrombosis, stenosis, or anastomotic breakdown. After perfusion fixation at 2 or 8 weeks, grafts underwent histological, morphometric, and immunohistochemical examination.


RESULTS
All animals survived without neurological or hemorrhagic complication. No deterioration of graft integrity (rupture, aneurysm) was observed in any group. Luminal narrowing was observed in both allograft groups, but secondary to different pathology. Fresh allografts had significant mononuclear cell infiltrate, intimal hyperplasia, and intramural hemorrhage consistent with rejection. Conversely, decellularized allografts had minimal evidence of rejection but instead had a compact fibrin layer formed along their lumen. This fibrin layer was absent in the peri-anastomotic regions where endothelium had migrated from the native artery. By 8 weeks, decellularized grafts had repopulated with cells staining positive for smooth muscle alpha-actin.


CONCLUSIONS
After 8 weeks of arterial flow, decellularized vein allograft exhibits satisfactory strength, reduced antigenicity compared to fresh allograft, and supports cellular repopulation. These characteristics make it satisfactory for further tissue engineering; combined with luminal vascular cell seeding, it may prove useful as a small-diameter arterial bypass graft.
Martin
Niels D
ND
Department of Surgery, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Schaner
Patrick J
PJ
Tulenko
Thomas N
TN
Shapiro
Irving M
IM
Dimatteo
Christopher A
CA
Williams
Timothy K
TK
Hager
Eric S
ES
DiMuzio
Paul J
PJ
D000818:Animals; D001696:Biomechanical Phenomena; D002339:Carotid Arteries; D004285:Dogs; D004730:Endothelium, Vascular; D005260:Female; D006084:Graft Rejection; D006965:Hyperplasia; D007150:Immunohistochemistry; D007601:Jugular Veins / Q000637:transplantation; D012967:Sodium Dodecyl Sulfate; D023822:Tissue Engineering / Q000379:methods*; D014184:Transplantation, Homologous / Q000276:immunology; D017539:Tunica Intima / Q000473:pathology; D014463:Ultrasonography; D014680:Veins / Q000637:transplantation*
D012967:Sodium Dodecyl Sulfate