Isolation and Characterization of Amniotic Fluid-Derived Extracellular Vesicles for Biomarker Discovery.

Amniotic fluid, the fetal-protective liquid that fills the amniotic sac, represents a rich source of biomarkers. The diagnostic utility of amniotic fluid relies on the highly abundant maternal and fetal nucleic acid and proteomic content, which allows for the simultaneous determination of mother and fetal health status. Extracellular vesicles (ECVs) that are released by all cells and found in amniotic fluid could be harnessed to provide substantial clinically actionable data. ECVs are mediators of critical biological functions and reflect the health of the parent cell. Thus, ECVs released from cells in distress may provide important diagnostic information. Here, we describe a straightforward and optimized method for isolating ECVs from amniotic fluid. In addition, we validate our procedure through western blotting using antibodies targeting canonical ECV protein markers and via direct visualization using transmission electron microscopy.