TABLE 1.

Summary of the minimal information for the study of extracellular vesicles (MISEV) guidelines.

Small EV characteristic	MISEV recommendation	Approaches	Analytic considerations
Quantity of EVs in a sample	- A quantified estimate of both the source of EVs (e.g., extracted whole blood/plasma volumes) and EVs themselves should always be provided	- Particle quantification (e.g., NTA, flow cytometry) - Total protein quantification (e.g., SDS page) - Total lipid quantification (e.g., SDS page)	- None of these methods exclusively quantify EVs - EV quantification is improved when methods are used in conjunction and to provide ratios indicative of purity, e.g., protein/particle or lipid/particle
EV marker identification	- At least three positive protein markers associated with EVs; including at least one transmembrane protein and one cytosolic protein - A purity control such as proteins that are identified as common contaminants (e.g., lipoproteins in plasma)	Traditional methods of protein identification (e.g., Western blot)	- “Mixed” signal may be determined across positive markers and therefore it is important multiple markers are used - High contaminant signal may have implications for interpretation of some quantification methods (e.g., NTA)
Characterization of single vesicles	- At least two different, but complimentary, methods of vesicle visualization should ideally be employed	- Microscopic-based techniques (e.g., electron or atomic force microscopy) - Single particle analyzers (e.g., NTA)	- Most microscopy techniques are not interchangeable in terms of the information they provide - Different techniques may need to be employed depending on the EV size range of interest

Modified from Théry et al. (2018).