TAT-血红素氧合酶-1融合蛋白对原位肝移植术大鼠肝细胞凋亡的影响

Effects of TAT-heme oxygenase-1 fusion protein on liver cell apoptosis in rats undergoing orthotopic liver transplantation

目的评价TAT-血红素氧合酶-1（TAT—HO-1）融合蛋白对原位肝移植术大鼠肝细胞凋亡的影响。方法健康成年雄性sD大鼠，体重250～280g，作为肝移植术的供体和受体。参照文献构建TAT—HO-1融合蛋白（1mg／m1）。采用二袖套法建立大鼠原位肝移植术模型。将受体大鼠随机分为2组（n=24）：对照组（c组）和融合蛋白组（TAT-HO-1组）。c组和TAT．HO-1组分别于肝移植术毕静脉注射生理盐水、TAT—HO-1融合蛋白10ml／kg。于无肝期前即刻（B）、肝脏移植术后1h、6h和12h（T1-3）时，分别取动脉血样，检测血清谷丙转氨酶（A坍）活性及透明质酸（HA）浓度；取肝组织标本，采用免疫组化法检测HO-1表达水平，采用TUNEL法检测凋亡细胞，计算凋亡指数。结果与C组比较，TAT—HO-1组T1-3时HO—1表达上调，血清ALT、HA水平及肝实质细胞和肝窦内皮细胞凋亡指数降低（P〈0．05）。结论大鼠原位肝移植术后静脉注射TAT—HO-1融合蛋白可转导进入移植肝脏细胞，通过减轻肝细胞和肝窦内皮细胞凋亡，对肝移植术后的肝脏功能发挥保护作用。

Objective To investigate the effects of TAT-heme oxygenase-1 （HO-1） fusion protein on liver cell apoptosis in rats undergoing orthotopic liver transplantation （OLT） . Methods Male adult SD rats, weighing 250-280 g, served as liver transplant donors and recipients. TAT-HO-I （1 mg/ml） was prepared according to the method described in the literatures. The model of OLT was established according to the two-cuff technique de- scribed by Kamada et al. The recipient rats were randomly divided into 2 groups （ n = 24 each） ： control group （ C group） and TAT-HO-1 group. Normal saline and TAT-HO-1 fusion protein 10 ml/kg were injected intravenously at the end of OLT in C and TAT-HO-1 groups respectively. Arterial blood samples were obtained immediately before anhepatic phase and at 1, 6 and 12 h after OLT （W1-3 ） to determine the serum ALT activity and hyaluronic acid （HA） concentration. Hepatic specimens were obtained to detect the expression of HO-1 （by immuno-histochemis- try） and apoptosis （using TUNEL）. Apoptotic index （AI） was calculated. Results Compared with group C, HO-1 expression was significantly increased, and the serum ALT and HA levels and the hepatic parenchymal and sinusoidal endothelial cell AI were significantly decreased in TAT-HO-1 group （ P 〈 0.05 ） . Conclusion TAT- HO-1 fusion protein injected intravenously after OLT can be transduced into the transplanted liver cells and protect the function of the transplanted liver through reducing apoptosis in the hepatocytes and sinusoidal endothelial cells in rats.