Long-term bone defects are a key clinical problem. Autogenous bone graft remains the gold standard for the treatment of these defects; however, improving the osteogenic properties and reducing the amount of autogenous bone is challenging. Autologous platelet-rich plasma (PRP) has been widely considered for treatment, due to its potentially beneficial effect on bone regeneration and vascularization. The aim of the present study was to explore the effects of autogenous bone particles combined with PRP on repairing segmental bone defects in rabbits. Briefly, a critical-size diaphyseal radius defect was established in 45 New Zealand White rabbits. Animals were randomly divided into four groups, according to the different implants: Group A, empty bone defect; group B, PRP; group C, autogenous bone particles + bone mesenchymal stem cells (BMSCs) on the left radius; group D, autogenous bone particles + PRP + BMSCs on the right radius. Bone samples were collected and further analyzed using X-ray, histology and histomorphometry 4, 8 and 12 weeks post-surgery. In addition, the effect of PRP on cell proliferation was detected by Cell Counting Kit-8 and the concentrations of growth factors (GFs), transforming GF (TGF)-β1 and platelet-derived GF (PDGF), in PRP were verified by ELISA. X-ray, histology and histomorphometry data revealed that the fraction area of the newly formed bone was larger in group D. In addition, PRP could improve cell proliferation, osteogenic differentiation and the release of GFs, TGF-β1 and PDGF-AB. In conclusion, these findings indicated that an autogenous bone particle + PRP + BMSC scaffold may be used as a potential treatment strategy for segmental defects in humans. Copyright: © Xie et al.