Comparison of the platelet-rich plasma and buffy coat protocols for preparation of canine platelet concentrates

Background: Platelet (PLT) concentrates (PC) can be produced via the buffy coat (BC) or platelet-rich plasma (PRP) protocols. The 2 methods have not been compared with canine blood. Objectives: The aims of the study were to compare the PLT, WBC, and RBC concentrations, in vitro PLT function, and markers of platelet storage lesion (PSL) in canine PC generated by 2 different protocols, and determine microbial growth throughout storage. Methods: PC from 8 healthy donor dogs were produced using 2 standard protocols, PRP and BC. PLT, WBC, and RBC counts, optical aggregometry assays, and PSL markers (pH, pCO₂, HCO₃, lactate and glucose concentrations, and LDH activity) were determined on storage days 0, 1, 3, 5, and 7. Aerobic and anaerobic bacterial cultures were also performed. Results: Mean PLT counts were comparable between protocols and remained stable throughout storage up to day 7, while median WBC and RBC counts on day 0 were significantly higher in the BC-PC group (17,800 WBCs/μL; 195,000 RBCs/μL) than in the PRP-PC group (200 WBCs/μL; 10,000 RBCs/μL) (P = .012). In PRP-PC aggregometry, the median slope and amplitude in response to γ-thrombin and convulxin (+ ADP) were significantly decreased, and virtually absent in BC-PC during storage. PSL markers (lactate, LDH activity) were higher in BC-PC. Aerobic bacterial growth was observed in 2 PRP-PC and 1 BC-PC. Conclusions: This in vitro study suggests that PRP-PC had lesser WBC and RBC contamination and superior PLT function compared with BC-PC. In vivo studies are required to address safety and efficacy of PRP-PC.