h DAF转基因猪在肝脏离体灌注实验中对超急性排斥反应的阻止作用

The effectiveness of the h DAF transgene in preventing hyperacute rejection of the liver in the isolated liver perfusion model

目的 在离体肝脏灌注实验中 ,观察人衰变加速因子 (hDAF)转基因猪对肝脏超急性排斥反应的阻止作用。方法 全麻下分别分离出门静脉、肝上及肝下下腔静脉、腹主动脉 ,分别经腹主动脉和门静脉插管 ,用UW液对肝脏进行原位灌注 ,然后摘取肝脏置于 4℃的冷容器中 ,冷缺血时间少于 1h ;灌注中 ,血液经肝下下腔静脉流出 ,循经膜氧和器—热交换器 ,然后经门静脉返回肝脏 ,血流速度 0 .75～ 1ml/克肝组织。共灌注 16只猪 ,将其分为猪血灌注猪肝脏组 (P P组 ,n =6)、人血灌注猪肝脏组 (H P组 ,n =5 )和人血灌注hDAF转基因猪肝脏组 (H hDAF组 ,n =5 )。结果 经组织学检查 ,P P组有正常的组织学结构 ;H P组显示有明显的血管内皮细胞的损害、出血、血小板及纤维蛋白的沉积 ;H hDAF组除 1例有轻度的血管内皮损害和出血外 ,其余为基本正常的组织学结构。H hDAF组在灌注过程中的胆汁产量、凝血功能及门脉压力的变化都明显好于H P组。结论 hDAF的转基因猪对肝脏的超急性排斥反应有明显的阻止作用 ,这为将来临床应用hDAF的转基因猪肝脏做体外灌注支持治疗提供了理论支持。

Objective The isolated livers were perfused in vitro to test the effectiveness of the h DAF transgene in preventing hyperacute rejection of the liver. Methods Under general anesthesia the portal vein, suprahepatic and infrahepaic vena cava, abdominal aorta were dissected respectively. The liver was perfused in situ through the abdominal aorta and portal vein cannula with UW solution. Thereafter, liver was procured and stored at 4℃. The cold ischemia time was less than 1 h. During the irrigating, blood was drained from the liver via an infrahepatic vena cava cannula, circulated through the membrane oxygenator and heat exchanger, then returned to the liver via the portal vein at a flow rate of 0.75 to 1?ml per gram of liver. Sixteen pigs received liver perfusions and were divided into the pig blood-pig liver group (P-P group, n=6), the human blood-pig liver group (H-P group, n=5) and the human blood-h DAF pig liver group (H-h DAF group,n=5). Results Histologically, the pigs in the P-P group were normal, those in the H-P group showed severe endothelial injury, marked hemorrhage, deposition of platelet and fibrin deposition, and those in H-h DAF group were relatively normal except one with mild endothelial change and hemorrhage. Moreover, the bile production, coagulation and portal pressure in the H-h DAF group were also better than in the H-P group significantly.Conclusions h DAF transgene could prevent the liver from an attack of the hyperacue rejection. Which provide a strong rationale to use the h DAF liver for the proposed human trials of extracorporeal liver support