Functionally Characterized Platelet-Rich Plasma Promotes Endothelial Migration and Cutaneous Wound Repair

Platelet-rich plasma (PRP) has been widely investigated as an autologous therapeutic for tissue regeneration; however, its clinical efficacy remains inconsistent, partly due to variability in PRP preparation protocols. In this study, we established an integrated framework for functional characterization of PRP by integrating platelet recovery, functional integrity, growth factor (GF) release, and regenerative outcomes. PRP prepared using a dual-spin centrifugation protocol at 92× g showed significantly higher platelet recovery while preserving functional responsiveness compared to single-spin conditions. PDGF-BB release increased in a time-dependent manner, peaking at 4 h after activation, and was positively correlated with platelet concentration. In an in vitro HUVEC scratch assay, PRP significantly enhanced endothelial cell migration in a platelet concentration-dependent manner. This migratory response was accompanied by increased phosphorylation of ERK and AKT and reduced VE-cadherin expression, indicating modulation of intracellular signaling pathways associated with endothelial cell growth, survival, and migration. In a rat skin wound model, PRP prepared under the selected experimental conditions accelerated wound closure compared with controls. Histological and immunohistochemical analyses revealed enhanced re-epithelialization, increased collagen deposition, increased epithelial cell proliferation, and reduced CD31-positive vascular area, consistent with accelerated vascular remodeling. Taken together, these findings demonstrate that PRP efficacy is governed by multiple interdependent factors. A comprehensive strategy integrating platelet recovery, functional preservation, GF release kinetics, and in vivo and in vitro outcomes provides a rational framework for functional characterization of PRP and may serve as a basis for subsequent translational validation.