Comparing small urinary extracellular vesicle purification methods with a view to RNA sequencing – enabling robust and non-invasive biomarker research

Extracellular vesicles (EVs) are 50-200nm small mediators in intercellular communication reflecting both physiological and patho-physiological changes of their parental cells. Thus, EVs bare great potential for biomarker detection, which has already been confirmed in cancer research. However, for the screening of the RNA cargo carried by urinary EVs by small RNA sequencing, reliable EV purification methods suitable for downstream analyses are still inconclusive. Therefore, total RNA was extracted from urinary EVs obtained by five different urinary EV purification methods (spin column chromatography, immunoaffinity, membrane affinity, precipitation and ultracentrifugation combined with density gradient). Further, their suitability in subsequent RNA sequencing was evaluated focusing on detected microRNAs.