Activation of equine platelet-rich plasma: comparison of methods and characterization of equine autologous thrombin.
Authors: Textor Jamie A, Tablin Fern
Journal: Veterinary surgery : VS
Summary
# Editorial Summary: PRP Activation Methods in Equine Practice Textor and Tablin compared four activation techniques for equine platelet-rich plasma (PRP)—autologous thrombin, bovine thrombin, calcium chloride, and freeze-thaw—to determine which most effectively releases growth factors critical for tissue repair. Using blood samples from six horses, they measured platelet-derived growth factor (PDGF-BB) and transforming growth factor beta-1 (TGF-β1) in the resulting releasate and analysed the composition and function of autologous thrombin preparations. Calcium chloride at 23 mM emerged as the superior activation method, producing significantly higher PDGF release than alternatives whilst maintaining comparable TGF-β levels, with the additional advantage that 80% of total PDGF remained bioavailable in the releasate rather than sequestered in the clot; conversely, autologous thrombin proved ineffective, triggering substantially less platelet aggregation than bovine thrombin and yielding the poorest growth factor release. For equine practitioners, these findings suggest that calcium chloride offers a practical, cost-effective activation protocol that reliably concentrates therapeutic factors in an easily administered releasate, whilst autologous thrombin should be abandoned in favour of established alternatives.
Read the full abstract on PubMed
Practical Takeaways
- •Use calcium chloride (23 mM) for PRP activation in clinical practice—it is inexpensive, effective, produces reliable growth factor release, and requires no specialized equipment compared to thrombin
- •Avoid autologous thrombin for PRP activation; it underperforms other methods in eliciting platelet growth factor release and platelet function
- •Understand that PRP releasate (the liquid portion) and the clot contain different concentrations of growth factors—choose activation method based on whether you need the liquid product or clot for your clinical application
Key Findings
- •CaCl₂ (23 mM) activation produced significantly greater PDGF-BB release than autologous thrombin, bovine thrombin, or freeze-thaw methods
- •Autologous thrombin was significantly less effective than all other activation methods and induced less platelet aggregation than bovine thrombin at 5 U/mL
- •CaCl₂-activated PRP releasate contained 80% of total PDGF content with comparable TGF-β release to other methods
- •Growth factor distribution differed between activation methods, with substantial concentrations retained in clots regardless of activation technique