Ten to twelve· week-old male inbred mice were obtained from the Jackson Laboratory, Bar Harbor, Me. Orthotopic liver transplantation was perfonned as described by Qian and coworkers. 1 Briefly, following cholecystectomy and cuff preparations. the liver grafts were placed orthotopically after the native liver had been removed. The suprahepatk vena cava anastomosis was completed with a 10-0 running suture. The cuff technique was used for anastomosis of both the infrabepatic vena cava and portal vein. No attempt was made to reconstruct the graft arterial supply. The donor bile duct was connected to that ofthe recipient by inserting a polyethylene tube in both. Blood loss was replaced with Ringer's Lactate solution. No immunosuppressive therapy was used in this study. Animals !i\;ng less than I week postoperatively were considered as surgical deaths, and were excluded from analysis. An autopsy was perfonned on all animals sun.iving more than I week, and tissue from the liver graft was submitted for histologic analysis. In addition, wedged resection biopsies were perfonned in some long-term survivors to assess the structural integrity of the graft and to check for rejection.