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Updated: Jul 4, 2026
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Uptake of Fluorescent Labeled Small Extracellular Vesicles In Vitro and in Spinal Cord
Published on: May 23, 2021
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Temporal and Severity-Dependent Alterations in Plasma Extracellular Vesicle Profiles Following Spinal Cord Injury
Jamie Cooper1, Scott Tait Airey1, Eric Patino1
1The Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
Cells
|July 25, 2025
Summary
Small extracellular vesicles (sEVs) in blood change with spinal cord injury (SCI) severity and time. These sEVs, particularly CD9+ vesicles, show potential as non-invasive biomarkers for monitoring SCI progression.
Area of Science:
- Neuroscience
- Biomaterials Science
- Cell Biology
Background:
- Spinal cord injury (SCI) induces complex local and systemic responses.
- Small extracellular vesicles (sEVs) mediate intercellular communication and may reflect disease dynamics.
Purpose of the Study:
- To investigate how SCI severity affects the composition and abundance of circulating plasma-derived sEVs.
- To explore the potential of sEVs as biomarkers for SCI progression.
Main Methods:
- Utilized a graded thoracic contusion model in mice.
- Isolated plasma-derived sEVs using size-exclusion chromatography.
- Characterized sEVs via nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and MACSPlex surface marker profiling.
Main Results:
- Observed an SCI-dependent increase in sEVs during the subacute phase (7 days), particularly in moderate injuries.
- Noted lower overall sEV counts in the chronic phase (3 months).
- Identified CD9 as the predominant tetraspanin marker, with dynamic regulation of CD41+, CD44+, and CD61+ within the CD9+ sEV subset.
Conclusions:
- sEV profiles evolve over time and vary with SCI severity.
- Dynamic changes in specific sEV surface markers suggest ongoing systemic signaling.
- Circulating sEVs hold promise as non-invasive biomarkers for monitoring SCI.
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