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Updated: Jul 23, 2026
09:16
Rapid Fluorescence-based Characterization of Single Extracellular Vesicles in Human Blood with Nanoparticle-tracking Analysis
Published on: January 7, 2019
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Enrichment protocols for human conjunctival extracellular vesicles and their characterization
Ismael Romero-Castillo1, Antonio López-García2, Yolanda Diebold2,3
1Ocular Surface Group, Instituto Universitario de Oftalmobiología Aplicada (IOBA), Universidad de Valladolid, Valladolid, Spain. iromeroc@ioba.med.uva.es.
Scientific Reports
|November 16, 2024
Summary
Ultrafiltration-precipitation efficiently isolates conjunctival extracellular vesicles (EVs). These EVs protect corneal cells from oxidative stress, highlighting UF-precipitation as the optimal method for conjunctival EV enrichment.
Area of Science:
- Ophthalmology
- Cell Biology
- Biotechnology
Background:
- Extracellular vesicles (EVs) play crucial roles in tissue function, but their role in the conjunctiva, vital for corneal protection, is understudied.
- Understanding conjunctival EVs is key to advancing ocular surface disease research and therapies.
Purpose of the Study:
- To comparatively isolate and characterize EVs from human conjunctival epithelial and mesenchymal stromal cells.
- To evaluate different isolation methods for their efficiency and yield.
- To assess the protective function of conjunctival EVs against oxidative stress in vitro.
Main Methods:
- Comparative isolation of EVs using differential ultracentrifugation (UC), ultrafiltration-precipitation (UF-precipitation), and ultrafiltration-size exclusion chromatography (UF-SEC).
- Characterization of EVs via protein content, size (Dynamic Light Scattering), morphology (Atomic Force Microscopy), and marker expression (Western Blotting).
- In vitro testing of EV functional effects on IM-HConEpiC cells under oxidative stress conditions.
Main Results:
- All three methods successfully recovered EVs, with UF-precipitation yielding significantly higher amounts.
- UC-isolated EVs were larger than those from UF-precipitation and UF-SEC.
- Conjunctival mesenchymal stromal cell (Conj-MSC)-derived EVs demonstrated significant protection against oxidative stress in epithelial cells.
Conclusions:
- Ultrafiltration-precipitation is the most efficient method for isolating and enriching extracellular vesicles from conjunctival cells.
- Conjunctival EVs, particularly those from mesenchymal stromal cells, possess protective properties against oxidative stress, relevant for corneal health.
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