From the Guidelines
Calcium chloride is typically required for PRP (platelet-rich plasma) activation. When preparing PRP for clinical applications, calcium chloride is added to initiate the coagulation cascade and activate platelets, causing them to release their growth factors and bioactive proteins. The calcium ions serve as essential cofactors in the clotting process, converting prothrombin to thrombin, which then converts fibrinogen to fibrin and triggers platelet activation.
Key Points
- The standard concentration used is usually 10% calcium chloride, added at a ratio of approximately 0.05 mL per 1 mL of PRP 1.
- Without calcium chloride or another activation agent, PRP remains in an inactive state since the anticoagulant (typically sodium citrate or ACD-A) used during collection binds calcium and prevents clotting.
- Some protocols use alternative activation methods such as thrombin, collagen, or mechanical activation through freeze-thaw cycles, but calcium chloride remains the most common activator due to its effectiveness, safety, and low cost 1.
- The activation process is crucial for therapeutic efficacy as it enables the release of growth factors that promote tissue healing and regeneration.
Considerations
- The use of calcium chloride for PRP activation is supported by recent guidelines, including the European guideline on management of major bleeding and coagulopathy following trauma: sixth edition 1.
- The importance of calcium ions in the coagulation cascade and platelet activation is well-established, with calcium chloride being the preferred agent for correcting hypocalcaemia in patients with critical bleeding requiring massive transfusion 1.
- While alternative activation methods exist, calcium chloride remains the most widely used and recommended activator for PRP due to its simplicity, effectiveness, and low cost 1.
From the Research
Calcium Chloride in PRP Activation
- Calcium chloride is commonly used to activate platelets in platelet-rich plasma (PRP) 2.
- The addition of calcium chloride to PRP leads to the direct activation of platelets, which facilitates clot formation 2.
- Studies have shown that calcium chloride can induce the release of growth factors from platelets, including transforming growth factor-β1 (TGF-β1), vascular endothelial growth factor (VEGF), and platelet-derived growth factor-BB (PDGF-BB) [(3,4,5)].
Comparison of Activation Methods
- Different activation methods, including calcium chloride, calcium gluconate, and thrombin, have been compared in terms of their ability to release growth factors from PRP [(3,4,5)].
- The choice of activation method can affect the release of bioactive molecules from PRP, with calcium chloride inducing a progressive release of growth factors over time 5.
- A study found that the combination of repeated freeze-thaw cycles and sonication may be the best treatment method to promote PRP to release growth factors, while calcium gluconate was found to be the weakest way 3.
Optimization of PRP Activation
- The optimization of PRP activation protocols has been investigated, with a focus on reducing the amount of anticoagulant and activator used 6.
- A study found that reducing the amount of sodium citrate and calcium chloride used in the PRP protocol led to a statistically significant higher enrichment and recovery of platelets, as well as improved platelet function and growth factor content 6.