EV Terminology Reference

The extracellular vesicle glossary.

Field-precise definitions for the terminology that appears across this site and across the EV literature. Each term has a stable anchor — copy the URL to share a definition directly.

Extracellular vesicle (EV)#: A nanoscale, bilayer-membrane-enclosed particle naturally secreted by cells. The umbrella class containing exosomes, microvesicles (ectosomes), and apoptotic bodies — distinguished from each other by biogenesis route, not by size alone.
Exosome#: An EV subpopulation that originates from the multivesicular body (MVB) pathway and is released into the extracellular space when an MVB fuses with the plasma membrane. Typically 30–150 nm. A product can only be called an exosome if biogenesis is demonstrated — size alone is insufficient.
Microvesicle (ectosome)#: An EV subpopulation that buds directly outward from the plasma membrane. Typically 100–1,000 nm. Distinct from exosomes by origin even when size ranges overlap.
Apoptotic body#: An EV subpopulation released during programmed cell death. Typically 1–5 µm. Not the relevant active fraction in dermocosmetic or regenerative EV products.
Plant-derived extracellular vesicle (PDEV)#: EVs isolated from plant tissues (e.g. Aloe barbadensis leaf parenchyma) rather than mammalian cells. Distinct from animal-derived EVs in safety profile, regulatory pathway, and scalability. The starting material for BioThera's mPDEV Serum.
mPDEV#: BioThera's professional-grade plant-derived EV dermocosmetic serum, formulated from Aloe barbadensis-derived EVs. Health Canada cosmetic notification complete; characterized to MISEV2023 standards on every batch.
MISEV2023#: Minimal Information for Studies of Extracellular Vesicles, 2023 update — the field-defining international consensus guidelines for EV research published by the International Society for Extracellular Vesicles (ISEV). Specifies the minimum characterization, reporting, and quality controls required to defensibly call a preparation an EV product.
ISEV#: International Society for Extracellular Vesicles — the global scientific society that authors and maintains the MISEV consensus guidelines and serves as the primary professional body for EV research.
EV biogenesis#: The intracellular pathway by which an EV is produced. The three recognised routes — multivesicular body fusion (exosomes), plasma-membrane budding (microvesicles), and apoptotic blebbing (apoptotic bodies) — are how the field distinguishes EV subpopulations. Biogenesis, not size, defines an exosome.
Multivesicular body (MVB)#: A late endosomal compartment containing intraluminal vesicles. When an MVB fuses with the plasma membrane, those intraluminal vesicles are released to the extracellular space as exosomes.
Nanoparticle Tracking Analysis (NTA)#: A light-scattering measurement that sizes and counts nanoparticles in suspension by tracking their Brownian motion. The field standard for reporting EV particle concentration (particles/mL) per batch. Required orthogonal characterization under MISEV2023.
EV-associated marker panel#: A set of protein markers — CD9, CD63, CD81 (tetraspanins); TSG101 and Alix (ESCRT-associated); plus markers for absence-of-contaminants — used together to demonstrate that a preparation is enriched for EVs rather than for cell debris, protein aggregates, or other nanoparticles.
Certificate of Analysis (CoA)#: A batch-specific quality document reporting the measured properties of a single production lot: particle concentration (NTA), EV marker panel, contamination screen, isolation method, and storage conditions. A generic product specification sheet is not a CoA — it must be batch-specific.
Biomolecular corona#: The layer of proteins, lipids, and other biomolecules that adsorb to an EV's outer membrane and travel with it through purification and into the final product. The corona is part of the active ingredient. Two preparations from the same biomass can carry different coronas depending on isolation method.
Isolation method#: The technique used to separate EVs from their source biomass. Common methods include ultracentrifugation, density gradient, ultrafiltration, size-exclusion chromatography, and tangential flow filtration. Different methods preserve or strip the biomolecular corona to different extents, which changes what the final product actually is.
Ultracentrifugation#: High-speed centrifugation (>100,000 × g) used to pellet EVs. Effective at enrichment but mechanically stressful — can strip components of the biomolecular corona and aggregate vesicles. Disclosed in the CoA where applicable.
Ultrafiltration#: Pressure-driven separation across a porous membrane sized to retain EVs while letting smaller solutes pass. Gentler than ultracentrifugation; corona retention depends on membrane choice and conditions.
Particle concentration#: EV count per unit volume, typically reported as particles/mL by NTA. A measured, batch-specific number — not a marketing estimate. mPDEV reports approximately 30 billion particles/mL.
Aloe barbadensis#: The botanical species (commonly 'aloe vera') whose leaf parenchyma is the biomass source for mPDEV. Aloe barbadensis-derived EVs carry an antioxidant-, anti-inflammatory-, and wound-healing-associated proteome consistent with the documented biological profile of the parent plant.
Cross-kingdom signalling#: Uptake and biological effect of plant-derived EVs by mammalian cells. Preclinical evidence supports cargo transfer and modulation of mammalian gene expression in model systems. Clinical translation in human skin is an active area; BioThera's framing treats this as supported in vitro and under evaluation in vivo.
Health Canada Cosmetic Notification#: The mandatory notification a cosmetic manufacturer must file with Health Canada under the Cosmetic Regulations (C.R.C., c. 869) within ten days of first sale in Canada. mPDEV is a notified cosmetic under this framework.
MoCRA#: Modernization of Cosmetics Regulation Act of 2022 — the framework requiring US cosmetic facility registration and product listing with the FDA. BioThera's FDA / MoCRA alignment is in progress; direct US clinic supply opens at completion.
TRL (Technology Readiness Level)#: A 1–9 scale used by NASA, ESA, and Industry Canada to describe how mature a technology is. BioThera's dermocosmetic application currently operates at TRL 7–8 — system prototype demonstrated in operational environment via dermatologist-led clinical evaluation, with manufacturing process complete and qualified under Health Canada Cosmetic Regulations.
CD9, CD63, CD81 (tetraspanins)#: Membrane proteins commonly enriched on EVs. Together they are one of the canonical EV-positive marker sets used to demonstrate that a preparation is EV-enriched.
TSG101 / Alix#: ESCRT-machinery-associated proteins involved in MVB biogenesis. Detection in a preparation supports an exosome (MVB-derived) origin and is part of the standard MISEV2023 marker panel.
Hollow-fibre bioreactor#: A bioreactor format in which cells or plant tissue are cultured against semi-permeable hollow fibres, enabling perfusion at high cell density and continuous harvest of secreted EVs. The format BioThera builds toward for scalable EV biomanufacturing.
EV biomanufacturing#: The full upstream-plus-downstream production of EV products at scale: biomass sourcing, culture or extraction, isolation, characterization, formulation, fill-finish, and batch release. BioThera's platform is full-stack across that pipeline.
EV characterization#: The set of orthogonal measurements used to describe an EV preparation: particle size and count (NTA), morphology (TEM), protein markers (Western blot, proteomics), and contamination screening. MISEV2023 specifies the minimum reporting requirements.
Cold-chain integrity#: Maintenance of a defined temperature range from manufacturer to point of use. Required for biologically active EV preparations to preserve membrane and corona integrity. Verifiable via packaging, shipping records, and where required, transit excursion logs.
PRP (platelet-rich plasma)#: An autologous blood-derived preparation enriched for platelets and platelet growth factors. Comparable to EV serums in that both deliver growth-factor-rich biological inputs to skin; differs in origin, batch consistency, regulatory pathway, and delivery format. Treated as complementary rather than competitive in BioThera's editorial framing.

Keep reading

Long-form context on these terms

Most of these definitions show up across the blog in working context. Start with the biogenesis explainer, or skip ahead to the MISEV2023 pillar.

MISEV2023 pillar EV biogenesis explainer