Proteomic Analysis of Preeclampsia Amniotic Fluid Based on a Novel Solid-State Preservation Method

Area of Science:

• Reproductive biology and perinatal medicine
• Biomarker discovery and proteomics
• Clinical diagnostics and disease mechanisms

Background:

• Amniotic fluid (AF) is vital for diagnosing and predicting perinatal diseases like preeclampsia (PE).
• Effective preservation of AF samples is crucial for developing PE biomarkers and understanding disease mechanisms.
• Current AF preservation methods may impact protein integrity, potentially hindering research.

Purpose of the Study:

• To develop and validate a novel method for preserving proteins in AF samples using a solid nitrocellulose membrane (AF membrane).
• To compare the efficacy of the AF membrane method with direct freezing for AF protein preservation.
• To identify differentially expressed proteins and pathways in AF from PE patients versus normotensive subjects.

Main Methods:

• AF samples from normotensive and PE subjects were preserved using direct freezing or the AF membrane method.
• Protein quality was assessed using SDS-PAGE and capillary electrophoresis.
• Proteomic analysis was performed using liquid chromatography tandem mass spectrometry (LC-MS/MS) with data-independent acquisition, followed by bioinformatics analysis.

Main Results:

• The AF membrane method showed no significant impact on AF protein content or quality compared to direct freezing.
• No evident protein differences or degradation were observed between preservation methods or groups.
• Bioinformatics analysis revealed upregulated pathways (angiotensin, ROS, coagulation) in PE patients and elevated levels of known PE serum biomarkers in AF.

Conclusions:

• The AF membrane method is a highly effective, reliable, and durable technique for preserving AF proteins.
• Solid-state preservation of AF samples is valuable for discovering novel protein biomarkers for PE.
• This method facilitates further investigation into the underlying mechanisms of preeclampsia.