孕中期甲胎蛋白异质体在唐氏综合征筛查中的临床意义

摘要

Objective The purpose was to examine the utility of analyzing variants of alpha-fetoprotein (AFP-L3) assessed by lectin affinity in Down’s syndrome (DS) screening. Methods Maternal sera were collected from 30 women who were carrying DS fetuses and 300 unaffected pregnancies around 16 weeks of gestation. Total AFP and AFP-L3 in maternal serum were determined by chemiluminescence immunoassay, while the AFP-L3 were extracted by lens culinaris agglutinin (LCA)-coupled spin columns. Results Total AFP decreased in maternal serum from DS-affected versus unaffected pregnancies while AFP-L3 levels signiifcantly increased (P<0.05) in maternal serum from DS-affected versus unaffected pregnancies. The receiver operating curves (ROC) line area of AFP-L3 is 0.710, the percentage of AFP-L3≥10%as the boundary distinguish between pregnant women with DS and normal pregnant women. Conclusion Our data suggest that the measurement of AFP-L3 in maternal serum is a potential biochemical marker for DS.%目的评价甲胎蛋白异质体（AFP-L3）在唐氏综合征筛查中的临床意义。方法取孕中期30例经确诊为唐氏综合征孕妇及300例正常孕妇的血清，运用凝集素微量离心柱法提取AFP-L3，以全自动发光法分别测定血清中甲胎蛋白（AFP）及AFP-L3浓度，评估AFP-L3比率与唐氏综合征的相关性。结果唐氏综合征孕妇血清中AFP浓度低于正常孕妇[（18.5±5.7）ng/ml∶（26.1±4.8）ng/ml， P＜0.05]，而AFP-L3比率高于正常孕妇[（28.3±3.2）％∶（13.3±4.5）％，P＜0.05]。AFP-L3比率的受试者工作曲线（ROC）线下面积（AUC）的值为0.710，显示以AFP-L3比率≥10%为界限可以很好地区分唐氏综合征孕妇和正常孕妇。结论 AFP-L3比率可作为唐氏综合征筛查的血清学指标之一。