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.

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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