Polymer-based precipitation preserves biological activities of extracellular vesicles from an endometrial cell line

Extracellular vesicles (EVs) are membrane-bound vesicles released by cells and act as media for transfer of proteins, small RNAs and mRNAs to distant sites. They can be isolated by different methods. However, the biological activities of the purified EVs have seldom been studied. In this study, we compared the use of ultracentrifugation (UC), ultra-filtration (UF), polymer-based precipitation (PBP), and PBP with size-based purification (PBP+SP) for isolation of EVs from human endometrial cells and mouse uterine luminal fluid (ULF). Electron microscopy revealed that the diameters of the isolated EVs were similar among the tested methods. UF recovered the highest number of EVs followed by PBP, while UC and PBP+SP were significantly less efficient (P