Case study: first implantation of a frozen, devitalized tissue-engineered vascular graft for urgent hemodialysis...

Previously we reported on the mid- to long-term follow-up in the first clinical trial to use a completely autologous tissue-engineered graft in the high pressure circulation. In these early studies, living grafts were built from autologous fibroblasts and endothelial cells obtained from small skin and vein biopsies. The graft was assembled using a technique called tissue-engineering by self-assembly (TESA), where robust conduits were grown without support from exogenous biomaterials or synthetic scaffolding. One limitation with this earlier work was the long lead times required to build the completely autologous vascular graft. Here we report the first implant of a frozen, devitalized, completely autologous Lifeline™ vascular graft. In a departure from previous studies, the entire fibroblast layer, which provides the mechanical backbone of the graft, was air-dried then stored at -80°C until shortly before implant. Five days prior to implant, the devitalized conduit was rehydrated, and its lumen was seeded with living autologous endothelial cells to provide an antithrombogenic lining. The graft was implanted as an arteriovenous shunt between the brachial artery and the axillary vein in a patient who was dependent upon a semipermanent dialysis catheter placed in the femoral vein. Eight weeks postoperatively, the graft functions without complication. This strategy of preemptive skin and vein biopsy and cold-preserving autologous tissue allows the immediate availability of an autologous arteriovenous fistula, and is an important step forward in our strategy to provide allogeneic tissue-engineered grafts available "off-the-shelf".