Possible cause of primary graft non-function after orthotopic liver transplantation: a hypothesis with rat models

The cause of primary graft non-function after orthotopic liver transplantation (OLTX) is uncertain, but its clinical features are similar to fulminant hepatic failure with coagulopathy. In preserved livers, endothelial cell damage in the hepatic sinusoids is characteristic, indicating that fibrin deposition in the hepatic sinusoids, which can cause massive hepatic necrosis, might occur in the liver after OLTX. When rat liver was preserved in University of Wisconsin solution at 1 degree C, detachment of endothelial linings into sinusoidal lumens developed with fat-storing cell damage after 18 h. In this liver, hepatic macrophages were activated after reperfusion. Tissue factor activity in hepatic macrophages isolated from livers after OLTX was significantly increased compared to the control liver and this increase was enhanced by addition of endotoxin. In the preserved and transplanted livers, thrombomodulin expression in endothelial cells disappeared and fibrin deposition was seen in the hepatic sinusoids. Intravenous infusion therapy with antithrombin III attenuated liver injury 24 h after OLTX following preservation for 18 h. These results suggest that intravascular coagulation in the hepatic sinusoids associated with liver injury occurs in the liver after OLTX following cold preservation. This coagulopathy may be caused by sinusoidal endothelial cell damage due to regulatory imbalance in coagulation as a result of increased tissue factor activity in hepatic macrophages and decreased thrombomodulin activity in sinusoidal endothelial cells. Fat-storing cell damage may also contribute to the endothelial cell damage. A hypothesis regarding the cause of primary graft non-function after OLTX is proposed.