胆道闭锁肝内胆管上皮E-cadherin的表达及其与细胞凋亡相关性研究

The abnormal expression of E-cadherin in intrahepatic bile duct epithelial cells in biliary atresia and its relationship with apoptosis

目的研究胆道闭锁(biliaryatresia,BA)肝内胆管上皮Ecadherin的表达及胆管上皮细胞凋亡情况,初步探讨其与BA发生的关系。方法应用Ecadherin免疫组化染色方法和末端脱氧苷酸转移酶介导的脱氧三磷酸尿苷(Dutp)缺口末端标记技术(TUNEL法)观察38例胆道闭锁患儿与16例正常对照儿童肝内胆管上皮Ecadherin表达及胆管上皮细胞凋亡情况。结果胆道闭锁患儿肝内胆管上皮Ecadherin表达强度0.33±0.12较正常对照0.62±0.20显著降低(P<0.01),胆管上皮细胞凋亡指数为0.5174±0.1993明显高于正常对照0.1234±0.1932(P<0.01),BA组肝内胆管上皮Ecadherin表达强度与胆管上皮细胞凋亡指数呈显著负相关(r=-0.853)。结论BA发生与肝内胆管上皮Ecadherin异常降低有关,可能是通过异常降低的Ecadherin上调胆管上皮细胞凋亡数量,导致肝内胆管发育障碍,产生“胆管板畸形”的方式来实现的。

Objective To explore the relationship between the expression of E-cadherin and the apoptosis in intrahepatic bile duct epithelial cells in biliary atresia (BA). Methods The E-cadherin expression was demonstrated by immunohistochemical staining for the liver specimens from 38 children with BA and 16 normal children. The apoptotic intrahepatic bile duct epithelial cells in these specimens were visualized by TdT-mediated dUTP-digoxigenin nick end labeling (TUNEL) assay, and the apoptotic index (AI) was calculated from the percentage of apoptotic cells in total cells. Results The intensity of E-cadherin expression in bile duct epithelial cells in BA group was lower than that in the normal control group ( 0.33± 0.12 vs 0.62± 0.20, P< 0.01). On the other hand, the AI in BA group was significant higher than that in control group ( 51.74± 19.93 vs 12.34± 19.32, P< 0.01). An inverse correlation was detected between the intensity of E-cadherin and the AI in the liver from children with BA. Conclusions The abnormal decrease of E-cadherin may lead to an increase of the apoptosis of intrahepatic bile duct epithelial cells in BA, resulting in developmental disorder of intrahepatic bile duct and ductal plate malformation in the liver.