Differential proteomics analysis of amniotic fluid in pregnancies of increased nuchal translucency with normal karyotype

Objectives To investigate the functional roles of differentially expressed proteins in amniotic fluid supernatant (AFS) from normal karyotype pregnancies with increased nuchal translucency (NT). Methods AFS from fetuses with increased NT (>3.4 mm, N = 14) and control (<0.7 mm, N = 14) were analyzed by two-dimensional electrophoresis and in-gel digestion to identify the difference of expressed proteins between both groups. Targeted proteins were confirmed by western blot and ELISA. The roles of biological networks in pathophysiology of NT were determined using MetaCore mapping. Results Levels of apolipoprotein-A1 (Entrez Gene ID 335), alpha-1 antitrypsin (SERPINA1, ID 5265) and prolactin (ID 5617) were significantly decreased in AFS of fetuses with increased NT compared with those in controls. According to Gene Ontology terms, biological processes of functional networks were mainly involved in steroid metabolism. On the basis of the database of MetaCore, these proteins are considered as the potential biomarkers of cardiovascular disorders. The prediction of tissue distribution from this network in fetal organs such as liver, skin, and kidney supported that these three proteins may play different roles between two groups. Conclusion The combination of using quantitative proteomics and functional network analysis could integrally analyze the pathophysiology of fetuses with increased NT. Copyright (C) 2011 John Wiley & Sons, Ltd.