Rate zonal centrifugation can partially separate platelets from platelet-derived vesicles

Area of Science:

• Biotechnology
• Cell Biology
• Biomarker Discovery

Background:

• Centrifugation is a standard method for enriching blood biomarkers, separating them by density or diameter.
• Current centrifugation protocols can lead to co-isolation of platelets and extracellular vesicles (EVs), affecting biomarker purity.
• Optimizing separation techniques is crucial for accurate biomarker analysis.

Purpose of the Study:

• To evaluate the efficacy of rate zonal centrifugation (RZC) in separating platelets from co-isolated EVs.
• To determine if RZC can improve the purity of platelet and EV isolates from blood samples.

Main Methods:

• Rate zonal centrifugation (RZC) was performed using a linear Optiprep gradient.
• The method was validated using polystyrene beads of varying diameters (140 nm, 380 nm, 1000 nm).
• RZC was applied to blood samples containing platelets and platelet-derived EVs, followed by flow cytometry analysis using anti-CD61-Alexa 488 staining.

Main Results:

• RZC successfully separated beads based on diameter, confirming its separation capability.
• Platelets were predominantly found in fractions 8-19, while EVs were mainly in fractions 1-7.
• The observed separation of different platelet size ranges within fractions indicates diameter-based separation.

Conclusions:

• Rate zonal centrifugation (RZC) demonstrates the ability to partially separate platelets from EVs.
• This technique offers potential for enhanced purity of biomarker isolates.
• Further optimization may improve the resolution of platelet and EV separation.