Comprehensive proteomic analysis of the human amniotic fluid proteome: gestational age-dependent changes

Area of Science:

• Proteomics
• Biochemistry
• Maternal-Fetal Medicine

Background:

• Amniotic fluid (AF) is crucial for fetal development and contains potential biomarkers for diagnosing maternal and fetal conditions.
• Understanding the AF proteome is essential for advancing diagnostic capabilities.

Purpose of the Study:

• To conduct a comprehensive protein survey of amniotic fluid.
• To identify proteins unique to AF and compare AF proteome with maternal serum and cervico-vaginal fluid.
• To analyze proteomic changes in AF across different trimesters of pregnancy.

Main Methods:

• Combined gel-based and liquid-based fractionation techniques.
• Liquid chromatography-tandem mass spectrometry (LC-MS/MS) for protein identification.
• Two-dimensional differential in-gel electrophoresis (2D-DIGE) for comparative proteomic analysis across trimesters.

Main Results:

• Identified a total of 219 nonredundant proteins in amniotic fluid.
• Discovered 96 proteins unique to AF, with 70, 18, and 35 proteins shared with serum, cervico-vaginal fluid, and all three fluids, respectively.
• Maximal differences in AF protein abundance were observed between the first and second trimesters.

Conclusions:

• The AF proteome is distinct and offers a rich source for biomarker discovery.
• Comparative proteomic analysis highlights significant changes during early pregnancy.
• Identifying shared proteins between AF and maternal serum could enable the development of noninvasive fetal diagnostic tools.