What are extracellular vesicles?
Extracellular vesicles (EVs) are nano-sized lipid bilayer vesicles that are released by cells into the extracellular space. EVs consist of proteins, polynucleic acids (e.g. RNA and DNA), and lipids, and can be divided into several subsets including exosomes (also known as small EVs), microvesicles, and apoptotic bodies (sometimes collectively known as large EVs). Fundamental differences exist between these different types of EVs based on how they are produced (biogenesis), their protein content, and their size.
The predominant biological function of all EVs is to maintain cell-to-cell communication  and EVs have been found in many biological fluids including blood plasma, synovial fluid, and urine. So far EVs from eukaryotic cells such as endothelial cells, mesenchymal stem cells (MSCs), and neuronal cells have been extensively studied in pre-clinical and clinical research. Even so, EVs from prokaryotic cells and plants have been identified and are being studied as potential sources that influence human health and gut microbiota. There are also many exciting developments involving EVs, which can ultimately be translated to disease diagnostics, drug delivery, therapeutics, and vaccines.,
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