Optimization of pure platelet-rich plasma preparation: A comparative study of pure platelet-rich plasma obtained using different centrifugal conditions in a single-donor model.

While it has been proved that centrifugal conditions for pure platelet-rich plasma (P-PRP) preparation influence the cellular composition of P-PRP obtained, the optimal centrifugal conditions to prepare P-PRP have not yet been identified. In the present study, platelet-containing plasma (PCP) was prepared with the first-spin of different double-spin methods and P-PRP was prepared with different double-spin methods. Whole-blood analysis was performed to evaluate the cellular composition of PCP and P-PRP. The basal and ADP-induced CD62P expression rates of platelets were assessed by flow cytometry to evaluate the function of platelets in PCP and P-PRP. Enzyme-linked immune sorbent assay was performed to quantify interleukin-1β, tumor necrosis factor-α, platelet-derived growth factor AB and transforming growth factor β1 concentrations of PCP and P-PRP. Correlations between the cellular characteristics and cytokine concentrations of P-PRP were analyzed by Pearson correlation analysis. Effects of P-PRP on the proliferation, survival and migration of human bone marrow-derived mesenchymal stem cells and human articular chondrocytes were evaluated by a Cell Counting Kit-8 assay, live/dead staining and Transwell assay, respectively. The results showed that centrifugation at 160 × g for 10 min and 250 × g for 15 min successively captured and concentrated platelets and growth factors significantly more efficiently with preservation of platelet function compared with other conditions (P<0.05). The correlation analysis showed that the similar leukocyte concentrations and leukocyte-reducing efficiencies resulted in similar pro-inflammatory cytokine concentrations in P-PRP (P>0.05) and the maximization of platelet concentration, platelet enrichment factor, platelet capture efficiency and platelet function resulted in the maximization of growth factor concentrations in P-PRP obtained using the optimal conditions (P<0.05). Compared with P-PRP obtained under other conditions, P-PRP obtained under the optimal conditions significantly promoted the proliferation and migration of cells (P<0.05) and did not alter cell survival (P>0.05). Therefore, centrifugation at 160 × g for 10 min and 250 × g for 15 min successively with removal of the buffy coat as a crucial step may provide an optimal preparation system of P-PRP for clinical application.