Methods for exosome isolation and characterization

Extracellular vesicles are released from cells under both physiological and pathophysiological conditions. Exosomes are a class of extracellular vesicles that originate from intraluminal membranes, and their diameters vary from 30 to 150 nm. Like hormones and cytokines, exosomes play a critical role in cell-cell communication. Proper methods for exosome isolation and characterization facilitate accurate downstream analyses. This review summarizes both conventional and novel techniques for exosome isolation and characterization as well as their advantages and limitations. Novel methods for fractionating exosome subsets, defining exosomal cargo, tracking exosomes in vivo, and determining whether a protein is associated with the inside or outside of exosomes are also included in this review.