Fig. 1.

Overview of EV sizes, secretion mechanisms, cargo, and uptake/ effect on recipient cells. Exosomes are a small class of EVs (40–120 nm) released from cells after a multivesicular body (MVB) fuses with the plasma membrane and are enriched in miRNAs, protein, and some DAMPs. Microvesicles are 0.1- to 1-μm diameter EVs that bud from the plasma membrane in a highly regulated fashion containing miRNAs, proteins, DAMPs, and some organelles, such as mitochondria. Apoptotic bodies are large EVs, which are released from cells upon programmed cell death. While all EV classes can contain miRNA, mRNA, DAMPs, lipids, and proteins, apoptotic bodies are large enough that they can also encapsulate larger cellular organelles and histones (5). DAMP, damage-associated molecular pattern; EV, extracellular vesicle.