磷脂酰肌醇蛋白多糖3对胆道闭锁患儿的诊断价值及与肝纤维化的关系

The diagnostic value of glypican 3 in children with biliary atresia and its relationship with liver fibrosis

目的探讨磷脂酰肌醇蛋白多糖3(GPC3)在胆道闭锁(BA)患儿中表达水平及其与肝纤维化的关系。方法收集BA患儿41例(BA组)、胆总管囊肿(CC)患儿9例(CC组)、肝功能正常无其他肝胆疾病的体检健康婴儿12例(NC组)。用酶联免疫吸附试验(ELISA)检测3组血清GPC3水平,使用受试者工作特征(ROC)曲线评估GPC3对BA的辅助诊断价值。留取BA组和CC组肝组织样本,通过免疫组织化学染色和实时荧光定量PCR检测GPC3在患儿肝组织中表达水平,分析BA患儿GPC3与肝纤维化分级的关系。结果(1)BA组GPC3水平高于CC组和NC组(χ2=24.170,P<0.01)。BA组内日龄≤30 d(21例)及>30 d的患儿(20例)血清GPC3水平差异无统计学意义,但均高于CC组和NC组(χ2=24.210,P<0.01)。BA组内Ⅰ~Ⅱ级与Ⅲ~Ⅳ级患儿GPC3水平差异无统计学意义,但均高于CC组和NC组(χ2=24.390,P<0.01)。GPC3诊断BA的ROC曲线下面积为0.878(95%CI:0.792~0.965,P<0.01),敏感度为82.93%,特异度为80.95%,最佳临界值为0.639μg/L。(2)肝组织免疫组织化学检测结果显示,BA组肝组织中GPC3表达较CC组明显升高(Z=3.565,P<0.01);肝组织中GPC3的含量与肝纤维化分级呈正相关(rs=0.619,P<0.01)。BA组GPC3 mRNA表达较CC组上调(Z=7.361,P<0.05)。结论血清GPC3对BA的诊断及鉴别诊断有一定临床价值;BA肝组织中GPC3表达上调,其表达量与胆道闭锁的肝纤维化分级呈正相关。

Objective To investigate the expression levels of glypican 3(GPC3) and its association with liver fibrosis in children with biliary atresia(BA).Methods A total of 41 infants with BA(BA group),9 infants with choledochal cyst(CC group) and 12 healthy infants with normal liver function and no other hepatobiliary diseases by physical examination(NC group) were collected.Serum GPC3 levels were measured by enzyme-linked immunosorbent assay(ELISA) in the 3 groups.The receiver operating characteristic(ROC) curve was used to evaluate the auxiliary diagnostic value of GPC3 for BA.Liver tissue samples from the BA group and the CC group were retained to analyze the relationship between GPC3 and the grade of liver fibrosis in children with BA by measuring the expression levels of GPC3 by immunohistochemical staining and qPCR.Results(1) GPC3 levels were significantly higher in the BA group than those in the CC group and the NC group(χ^(2)=24.170,P<0.01).There were no significant differences in the serum levels of GPC3 in children aged≤30 d(n=21) and children aged>30 d(n=20) in the BA group,but which were higher than those in the CC group and the NC group(χ^(2)=24.210,P<0.01).There were no significant differences in GPC3 levels between grades Ⅰ to Ⅱ and grades Ⅲ to Ⅳchildren in the BA group,but which were higher than those in the CC group and the NC group(χ^(2)=24.390,P<0.01).The area under the ROC curve(AUC) of GPC3 for the diagnosis of BA was 0.878(95%CI:0.792-0.965,P<0.01),with a sensitivity of 82.93%,a specificity of 80.95%,and an optimal cut-off value of 0.639 μg/L.(2) The results of liver tissue immunohistochemistry showed that GPC3 expression in liver tissue was significantly increased in the BA group compared to that of the CC group(Z=3.565,P<0.01),and the content of GPC3 in liver tissue was positively correlated with the grade of liver fibrosis(r_(s)=0.619,P<0.01).The GPC3 expression was upregulated in the BA group compared to that of the CC group(Z=7.361,P<0.05).Conclusion The serum GPC3 has clinical value in the diagnosis and differential diagnosis of BA.GPC3 expression is upregulated in BA liver tissue,and its expression level is positively correlated with the grade of liver fibrosis in biliary atresia.