Urinary Extracellular Vesicles Magic Particles for Biomarker Discovery

Extracellular vesicles (EV) are small membrane-coated structures secreted by all cells of the body and can be detected in all bodily fluids, including urine. EV contents (e.g. proteins and distinct RNA classes) reflect the physiological state of their cells of origin, offering a new source of biomarkers. Accordingly, urinary Extracellular Vesicles (uEVs) are emerging as a source for early biomarkers of kidney damage and beyond, holding the potential to replace the conventional invasive techniques including kidney biopsy. However, the lack of standardization and sample collection and isolation methods, and the influence of factors such as inter- and intra-individual variability create difficulties in interpreting current results. Here we review recent results and reported uses of especially urinary EVs and also pinpoint approaches to be considered when designing experiments.