The study of extracellular vesicles (EVs) and nanoparticles (NPs) is rapidly expanding because recent discoveries have revealed a much greater complexity and diversity than was appreciated only a few years ago. New types of EVs and NPs have recently been described. Proteins and nucleic acids previously thought to be packaged in exosomes appear to be more enriched in different types of EVs and in two recently identified amembranous NPs, exomeres and supermeres. Thus, our understanding of the cell biology and intercellular communication facilitated by the release of EVs and NPs is in a state of flux. Researchers from Vanderbilt University Medical Center describe the different types of EVs and NPs, highlight recent advances, and present major outstanding questions.
The world of extracellular vesicles (EVs) and nanoparticles (NPs)
Most mammalian cells are between 10 and 100 μm in diameter and can release a diversity of heterogenous EVs and non-vesicular extracellular NPs (NVEPs) ranging in size from ~5 nm up to >5 μm. The overlapping sizes of many EVs and NVEPs make it difficult to separate them completely. Abbreviations: ACLY, ATP citrate lyase; ARMM, arrestin domain-containing protein 1-mediated microvesicle; ARRDC1, arrestin domain-containing protein 1; FASN, fatty acid synthase; HDL, high-density lipoprotein; HSPA13, heat shock protein family A (Hsp70) member 13; IDL, intermediate-density lipoprotein; LDL, low-density lipoprotein; MVP, major vault protein; SMAP, supramolecular attack particle; TGFBI, transforming growth factor beta-induced; TSP1, thrombospondin 1; VLDL, very low-density lipoprotein.