Summary
Objective: To compare five activation methods in equine platelet-rich plasma (PRP) by determination
of platelet-derived growth factor BB (PDGF-BB) and transforming growth factor beta
1 (TGF-β1) concentrations in platelet-rich gel (PRG) supernatants.
Methods: Platelet-rich plasma from 20 horses was activated by calcium chloride (CC), calcium
gluconate (CG), bovine thrombin (BT), and their combinations, BTCC and BTCG. Both
growth factor concentrations in PRG supernatants were measured by ELISA and compared
with plasma and platelet ly-sates (PL) over time.
Results: Growth factor concentrations were significantly lower in plasma and higher for all
PRG supernatants. Platelet lysates contained a significantly lower concentration of
PDGF-BB than PRG supernatants and a significantly higher concentration of TGF-β1 than
PRG supernatants. Clots from PRP activated with sodium salts were more stable over
time and had significant growth factor release, whereas CC produced gross salt deposition.
Significant correlations were noticed for platelet with leukocyte concentrations in
PRP (rs: 0.76), platelet counts in PRP with TGF-β1 concentrations in PRG supernatants (rs: 0.86), platelet counts in PRP with PDGF-BB concentrations in PRG super-natants (rs: 0.78), leukocyte counts in PRP with TGF-β1 concentrations in PRG supernatants (rs: 0.76), and PDGF-BB concentrations with activating substances (rs: 0.72).
Clinical significance: Calcium gluconate was the better substance to induce PRP activation. It induced growth
factor release free from calcium precipitates in the clots. Use of BT alone or combined
with calcium salts was not advantageous for growth factor release.
Keywords
Horse - platelet concentrates - platelet-derived growth factor BB - transforming growth
factor beta 1 - calcium salts - bovine thrombin - equine