Quantitative proteomic analysis of serum from pregnant women carrying a fetus with conotruncal heart defect using isobaric tags for relative and absolute quantitation (iTRAQ) labeling.

Ying Zhang,Xiaohui Liu,Yuan Kang,Huijun Wang,Duan Ma,Qiongjie Zhou,Hong Jin,Xiaotian Li,Jizi Zhou,Philippe Rouet

doi:10.1371/journal.pone.0111645

Abstract

ObjectiveTo identify differentially expressed proteins from serum of pregnant women carrying a conotruncal heart defects (CTD) fetus, using proteomic analysis.MethodsThe study was conducted using a nested case-control design. The 5473 maternal serum samples were collected at 14–18 weeks of gestation. The serum from 9 pregnant women carrying a CTD fetus, 10 with another CHD (ACHD) fetus, and 11 with a normal fetus were selected from the above samples, and analyzed by using isobaric tags for relative and absolute quantitation (iTRAQ) coupled with two-dimensional liquid chromatography-tandem mass spectrometry(2D LC-MS/MS). The differentially expressed proteins identified by iTRAQ were further validated with Western blot.ResultsA total of 105 unique proteins present in the three groups were identified, and relative expression data were obtained for 92 of them with high confidence by employing the iTRAQ-based experiments. The downregulation of gelsolin in maternal serum of fetus with CTD was further verified by Western blot.ConclusionsThe identification of differentially expressed protein gelsolin in the serum of the pregnant women carrying a CTD fetus by using proteomic technology may be able to serve as a foundation to further explore the biomarker for detection of CTD fetus from the maternal serum.

Highlights

Congenital heart defects (CHDs) comprise the most common type of human birth defects, occurring in approximately one in 100 live births [1,2,3]
Other conotruncal heart defects (CTD), another CHD (ACHD) and normal controls were confirmed by prenatal and postnatal echocardiography. 3 cases of fetal 21-trisomy, 7 cases of fetal multimalformation, 19 cases of fetal CHD which was diagnosed at birth, and 1 case combined with pregnancy–induced hypertension and fetal malformation were excluded
Western blot and IHC validation of the gelsolin protein expression in fetal heart tissue Having validated that GSN protein was downregulated in maternal serum with a CTD fetus, we examined the expression of GSN in 4 gestation week-paired CTD fetal hearts (23–25 gestational weeks), and 4 normal controls by Western blot and IHC

Summary

Introduction

Congenital heart defects (CHDs) comprise the most common type of human birth defects, occurring in approximately one in 100 live births [1,2,3]. There are no effective strategies for reducing the occurrence of CTDs, and no methods of early detection. Serum protein screening is an important diagnostic tool, with a rich source, good sensitivity and simplicity. Proteins originating from the placenta, amniotic fluid or fetus circulation may cross the placenta barrier and exist in maternal serum. Noninvasive procedures based on protein screening from maternal serum have been applied in the early screening of Down’s syndrome [16,17] by using the following serum markers: human chorionic gonadotropin (hCG), a-fetoprotein(AFP) [18], pregnancy-associated plasma protein (PAPP-A), unconjugated estriol (uE3) and inhibin-A [19]. An effective prenatal screening for CTDs is, lacking

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Conclusion