Compared with EVs in general, it is unclear whether exosomes have unique characteristics or functions or can be separated or distinguished effectively from other EVs. EVs including exosomes carry markers of cells of origin and have specialized functions in physiological processes, from coagulation and intercellular signalling to waste management. Consequently, there is a growing interest in clinical applications of EVs as biomarkers and therapies alike, prompting establishment of an International Society for Extracellular Vesicles (ISEV) and a scientific journal devoted to EVs, the "Journal of Extracellular Vesicles".