A multi-platform assessment of extracellular vesicles from the plasma and urine of women with preeclampsia

Introduction: MicroRNAs (miRNAs), packaged within extracellular vesicles (EVs), have been used to interrogate the pathogenesis of preeclampsia and to identify its biomarkers. We have previously shown that miRNA species were differentially expressed in small plasma EVs from women with preeclampsia vs healthy controls. We sought to assess the use of rapid technologies for isolation of plasma and urine EVs from parturients with preeclampsia and determine differences in the expression of selected EV miRNA species.

Methods: We collected blood and urine samples before delivery from parturients with severe preeclampsia vs healthy controls and used size exclusion chromatography (SEC) as an acceptable standard for rapid isolation of plasma EVs. We also isolated urine and plasma EVs using ExoDisc, a rapid nanofiltration technology for EV isolation. All samples were examined using a nanoparticle tracking analyzer, immunoblotting, and RT-qPCR for selected miRNA levels.

Results: Whereas the concentration of EVs was higher in the urine from preeclampsia compared to controls, we observed the opposite change in plasma EVs, with no difference in EV size. Comparing the two patient groups for miRNA levels in EVs isolated by ExoDisc or SEC, we found that EV miR-93-5p was upregulated in the plasma and urine of parturients with preeclampsia vs healthy controls. Notably, miR-31-5p was upregulated in SEC- or ExoDisc-isolated plasma EVs, and miR-92-3p was upregulated in or ExoDisc-isolated plasma or urine EVs of parturients with preeclampsia.

Discussion: Technologies for rapid analysis of plasma and urine EVs and their miRNA cargo provide complementary information that might be useful for deciphering pathways leading to preeclampsia and biomarkers for this disease.