Hallmarks of extracellular vesicles
| Characteristics | Exosomes | Microvesicles | Apoptotic bodies | Exophers | Migrasomes | Exomeres | Supremeres | Chromatimeres | Lipoproteins | Oncosomes |
|---|---|---|---|---|---|---|---|---|---|---|
| Size | 30∼150 nm | 100∼1,000 nm | 0.5∼5,000 nm | 3.5∼4 μm | <4 μm | ≤50 nm | N/A | N/A | ∼30 to 150 nm HDL (5∼15 nm) | 1∼100 μm |
| Shape | Spherical/cup shaped | Irregular | Irregular | Irregularly shaped but are typically spherical structures | Oval shaped | N/A | N/A | N/A | Lipoprotein-like structures, micelle-like structures | Cup-shaped vesicles |
| Density | 1.13∼1.19 g/ml | 1.25∼1.30 g/ml | 1.16∼1.28 g/ml | N/A | N/A | Lower density | Vary depending on their buoyant density | N/A | 0.930∼1.210 g/ml | Discrete buoyant densities |
| Sedimentation rate | 100,000∼200,000 |
10,000∼20,000 |
1,200, 10,000, or 100,000 |
N/A | N/A | N/A | N/A | N/A | N/A | N/A |
| Origin | Multivesicular bodies (endocytic pathway) | Plasma membrane | Various cell types | Evagination of the cell membrane | Tetraspanin- enriched macrodomain accumulation | N/A | N/A | N/A | Synthesized primarily in the liver | Cancer cells |
| Mechanism of release | Exocytosis (MVBs) (inward budding) | Outward budding of plasma membrane | Cell death causes cell shrinkage and blebbing of the plasma membrane | Pinching-off mechanism | Released from the retraction fibers during cell migration | N/A | N/A | N/A | Endogenous lipoprotein pathway | Shedding of plasma membrane blebs |
| Content | mRNA, miRNA, proteins, lipids | mRNA, miRNA, proteins, lipids | Proteins, nuclear segments, DNA, RNA, lipid cellular debris | Organelles, large protein complexes, aggregated, soluble proteins, and other cytoplasmic components | mRNA, protein, or damaged mitochondria, or as chemoattractive sources | Proteins, nucleic acids and lipids | N/A | DNA | Cholesterol | Distinct protein cargo, tumor DNA |
| Biomarkers | Exosomal markers- ALIX, TSG101, HSC70, CD63, CD9, CD81, and HSP90 | Selectins, integrins, CD40 | Histones, HSP60, GRP78 | N/A | N/A | N/A | N/A | N/A | Apolipoprotein B, sphingolipids/ ceramides | Cancer-specific biomarkers |
| Lipid composition | Cholesterol, sphingomyelin and ceramide-rich lipid rafts, low phosphatidylserine exposure | High phosphatidylserine exposure, cholesterol | N/A | Unknown lipid bilayer composition | N/A | Lipid bilayer membrane | N/A | N/A | Saturated and monoenoic fatty acids | N/A |
| Biological purpose | Cell-to-cell communication, migration, and maintenance, as well as a payload of proteins, DNA, and RNAs that imitate the parent cell | Role in intercellular communication | Efficient removal of cell debris | Related to autophagy | Cell migration | Intercellular communication | Large protein complexes, including ribosomes and proteasomes | Complex of DNA and proteins | Transport of lipids, immunomodulation | Oncogenic transformation, intercellular communication |
| Pathway | ESCRT- dependent and ESCRT– independent, constitutive dependent, stimuli dependent | Constitutive dependent, stimuli dependent Ca2 dependent |
Apoptosis dependent | Ubiquitin- proteasome system and autophagy- lysosome pathway | N/A | N/A | N/A | N/A | Exogenous and endogenous lipoprotein pathway | AKT1 and EGFR pathway, c-MET pathway |
| Quantification | DLS Nanoparticle tracking analysis TEM, SEM |
N/A | N/A | No standard methodologies | N/A | N/A | N/A | N/A | FRET-based assay, tunable resistive pulse sensing, flow cytometry | FRET-based assay, DLS |
| Isolation methods | Ultracentrifugation Size exclusion chromatography Tangential flow filtration EXO-Kit methods |
No standard methodologies | Ultracentrifugation | No standard methodologies | N/A | Ultracentrifugation and asymmetric- flow field-flow fractionation | Ultracentri-fugation, density gradient centrifugation | N/A | Ultracentrifugation, size exclusion chromatography | Physicochemical methods, ultracentrifugation |
N/A: not available, HDL: high density lipoprotein, MVBs: multi-vesicular bodies, ESCRT: endosomal sorting complex required for transport, DLS: dynamic light scattering.