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Updated: May 12, 2026

Isolation, Characterization, and Proteomic Analysis of Plasma-Derived Extracellular Vesicles for Cardiovascular Biomarker Discovery
Published on: January 31, 2025
Blood/plasma secretome and microvesicles
Jameel M Inal1, Uchini Kosgodage, Sarah Azam
1Cellular and Molecular Immunology Research Centre, School of Human Sciences, London Metropolitan University, 166-220 Holloway Road, London, N7 8DB, UK.
Abstract:
A major but hitherto overseen component of the blood/plasma secretome is that of extracellular vesicles (EVs) which are shed from all blood cell types. These EVs are made up of microvesicles (MVs) and exosomes. MVs, 100nm-1μm in diameter, are released from the cell surface, and are a rich source of non-conventionally secreted proteins lacking a conventional signal peptide, and thus not secreted by the classical secretory pathways. Exosomes are smaller vesicles (≤100nm) having an endocytic origin and released upon multivesicular body fusion with the plasma membrane. Both vesicle types play major roles in intercellular cross talk and constitute an important component of the secretome especially in the area of biomarkers for cancer. The release of EVs, which are found in all the bodily fluids, is enhanced in cancer and a major focus of cancer proteomics is therefore targeted at EVs. The blood/plasma secretome is also a source of EVs, potentially diagnostic of infectious disease, whether from EVs released from infected cells or from the pathogens themselves. Despite the great excitement in this field, as is stated here and in other parts of this Special issue entitled: An Updated Secretome, much of the EV research, whether proteomic or functional in nature, urgently needs standardisation both in terms of nomenclature and isolation protocols. This article is part of a Special Issue entitled: An Updated Secretome.
Insights
Extracellular vesicles (EVs), including microvesicles and exosomes, are key components of the blood secretome. Standardizing EV research is crucial for their use as biomarkers in cancer and infectious diseases.
Area of Science:
- Biochemistry
- Cell Biology
- Proteomics
Background:
- Extracellular vesicles (EVs), comprising microvesicles (MVs) and exosomes, are shed by all blood cells and are a significant, yet overlooked, part of the blood/plasma secretome.
- MVs (100nm-1μm) originate from the cell surface, carrying non-conventionally secreted proteins, while exosomes (≤100nm) have an endocytic origin.
- Both EV types are vital for intercellular communication and are increasingly recognized for their potential as biomarkers.
Purpose of the Study:
- To highlight the significance of extracellular vesicles (EVs) within the blood secretome.
- To emphasize the role of EVs as potential biomarkers for cancer and infectious diseases.
- To address the urgent need for standardization in EV research, including nomenclature and isolation protocols.
Main Methods:
- Review and synthesis of current literature on extracellular vesicles (EVs) in the context of the blood secretome.
- Analysis of the composition and origin of microvesicles (MVs) and exosomes.
- Discussion of the implications of EV research in cancer and infectious disease diagnostics.
Main Results:
- Extracellular vesicles (EVs) are a major component of the blood secretome, originating from various blood cell types.
- EVs, particularly microvesicles and exosomes, are implicated in intercellular signaling and are found in all bodily fluids.
- EV release is enhanced in cancer, making them a focus for cancer proteomics and biomarker discovery.
Conclusions:
- Extracellular vesicles (EVs) represent a critical, underappreciated element of the blood secretome with significant diagnostic potential.
- The enhanced release and presence of EVs in cancer and infectious diseases underscore their utility as biomarkers.
- Standardization of nomenclature and isolation techniques is urgently required to advance the field of EV research and application.
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