Concentration of platelets and growth factors in canine autologous conditioned plasma

Objectives: To report the concentration of blood cells and selected growth factors in canine autologous conditioned plasma (ACP). Methods: The density of blood cells in whole blood (WB), ACP and standard plasma preparation (SP) of 10 healthy mature dogs was determined. In both ACP and SP, the concentration of insulin-like growth factor-1 (IGF-1), epidermal growth factor, vascular endothelial growth factor, platelet-derived growth factor-AA, platelet-derived growth factor-AB, platelet-derived growth factor-BB, transforming growth factor-beta 1 (TGF-beta 1), and transforming growth factor-beta 2 was measured using the ELISA technique. In another ten dogs,ACP was prepared using an ultra-soft spinning protocol, and again blood cell density was compared to that obtained in WB. Results: The density of platelets in ACP was significantly higher than that in SP (p = 0.0002), but there was not any significant difference between ACP and WB, nor between WB and ACP prepared using softer centrifugations. Interestingly, only for IGF-1, PDGF-BB, and TGF-beta 1 could reliable measurements be obtained, showing a significant increase in PDGF-BB and TGF-beta 1 concentrations in ACP compared to SP (p = 0.001, p = 0.0028). Regarding IGF-1 content, there was not any significant difference between ACP and SP. Clinical significance: Canine ACP prepared according to the manufacturer's recommendations, or by using a softer spin does not show the same specifications as human ACP, which shows a doubling in platelet count compared to WB. Even though canine ACP has a similar number of platelets per injected volume and consequently, probably the same amount of injected growth factors than WB, application of canine ACP would not be associated with the proinflammatory potential reported for WB, as it is almost free of erythrocytes and nucleated cells.