Rapid isolation and enrichment of extracellular vesicle preparations using anion exchange chromatography.

Extracellular vesicles (EVs) have important roles in physiology, pathology, and more recently have been identified as efficient carriers of therapeutic cargoes. For efficient study of EVs, a single-step, rapid and scalable isolation strategy is necessary. Chromatography techniques are widely used for isolation of biological material for clinical applications and as EVs have a net negative charge, anion exchange chromatography (AIEX) is a strong candidate for column based EV isolation. We isolated EVs by AIEX and compared them to EVs isolated by ultracentrifugation (UC) and tangential flow filtration (TFF). EVs isolated by AIEX had comparable yield, EV marker presence, size and morphology to those isolated by UC and had decreased protein and debris contamination as compared to TFF purified EVs. An improved AIEX protocol allowing for higher flow rates and step elution isolated 2.4*10 EVs from 1 litre of cell culture supernatant within 3 hours and removed multiple contaminating proteins. Importantly AIEX isolated EVs from different cell lines including HEK293T, H1299, HCT116 and Expi293F cells. The AIEX protocol described here can be used to isolate and enrich intact EVs in a rapid and scalable manner and shows great promise for further use in the field for both research and clinical purposes.