Extracellular Vesicle (EV)

An extracellular vesicle (EV) is a particle released from a cell that is delimited by a lipid bilayer and cannot replicate on its own (it lacks a functional nucleus). EV is the field-recommended generic term, preferred over biogenesis-implying names like “exosome” or “ectosome” because most separation methods cannot confirm which subcellular compartment a given vesicle came from. EVs are one part of the broader category of “extracellular particles” (EPs), which also includes non-vesicular extracellular particles (NVEPs) — cell-derived assemblies such as lipoprotein or ribonucleoprotein particles that lack a delimiting lipid bilayer and often co-isolate with EVs in the same preparation.