Cellular remodeling of depopulated bovine ureter used as an arteriovenous graft in the canine model1

Randomized clinical trial comparing decellularized bovine ureter with expanded polytetrafluoroethylene for vascular access

“…The reduction in thrombotic events after 9 months may relate to the anticipated host remodelling of these biological grafts 9,10 . This process is analogous to the time required for arterialization of autologous vein grafts used as arterial replacement 19 .…”

“…Sequential treatment by hypotonic lysis, nuclease (deoxyribonuclease and ribonuclease) digestion and isotonic washout gently removes the cellular components of the ureter while preserving its collagen matrix, allowing implantation of this xenograft without immunosuppression. Unlike other biological grafts, the SG 100 is not chemically cross-linked, nor does it contain any external support, potentially permitting ingrowth of host cells into the matrix 9,10 . Mechanically, it is compliant and has dimensions suitable for anastomoses to upper arm vessels.…”

Current Status of Synthetic and Biological Grafts for Hemodialysis

“…SG 100 graft showed fibroblast cell migration and proliferation with incorporation into the surrounding subcutaneous tissue after 10 weeks, and procollagen synthesis demonstrated at 24 weeks; while the ePTFE graft had no evidence of cellular ingrowth. 39 In a study of 23 patients receiving SG 100 grafts, Darby et al found that the bovine ureter graft was a stable vascular access conduit, providing a suitable graft alternative when autologous vein was not available. Their study showed 29% primary, 45% primary assisted, and 81% secondary patency rates at 1 year, with only a 5% infection rate.…”

Incomplete cellular depopulation may explain the high failure rate of bovine ureteric grafts

“…The SynerGraft  (CryoLife, Atlanta, Georgia, USA) is produced by a unique, patented process whereby bovine ureters undergo hypotonic lysis and nuclease digestion, aiming to leave the acellular collagen matrix. Canine experiments found that the graft was incorporated via recellularization and neovascularization 9 . Early reports of its clinical application were promising, but its use in infrainguinal bypass has been questioned recently 10,11 .…”