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Updated: May 29, 2026
06:10
A Simple Double Centrifugation Tube Method to Obtain Platelet-rich Plasma from Equine Blood
Published on: August 15, 2025
Stimulus-dependent release of tissue-regenerating factors by equine platelets
B Dunkel1, D M Bolt, R K Smith
1Departments of Veterinary Clinical Sciences and Veterinary Basic Sciences, The Royal Veterinary College, UK.
Equine Veterinary Journal
|September 10, 2011
Summary
Equine platelet growth factor release depends on clot formation, not the stimulus. Coagulation triggers sustained release of both growth factors and inflammatory mediators, suggesting potential therapeutic applications.
Area of Science:
- Veterinary Medicine
- Regenerative Medicine
- Biochemistry
Background:
- Platelet-rich plasma (PRP) is widely used for equine orthopaedic injuries.
- Optimal protocols for PRP are not established due to unknown stimulus effects on equine platelet factor release.
Purpose of the Study:
- To identify a stimulus that maximizes regenerative factor release (platelet-derived growth factor BB [PDGF], transforming growth factor β1 [TGF]) without increasing inflammatory mediator (CCL5) release.
- To understand the dynamics of growth factor and inflammatory mediator release from equine platelets.
Main Methods:
- Washed equine platelets were stimulated with thrombin, chitosan, or equine recombinant tumor necrosis factor (erTNF).
- Growth factor and CCL5 release were measured over 24 and 96 hours using ELISAs.
- Non-coagulated samples were analyzed for comparison.
Main Results:
- PDGF and TGF release peaked within 0.5-1 hour upon clot formation, irrespective of the stimulus.
- Minimal growth factor release occurred in non-coagulated samples.
- CCL5 release was prolonged and not linked to coagulation, with erTNF inducing higher CCL5 levels at 6 hours.
Conclusions:
- Equine platelet growth factor release is triggered by coagulation, not the specific stimulus.
- Coagulation leads to sustained release of both growth factors and inflammatory mediators.
- Supernatants from coagulated platelets may offer an alternative to traditional PRP treatments.
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