Objective: To investigate the biocompatibility of human platelet-rich plasma (PRP) and human dental pulp cells (DPCs), and the effect of human platelet-rich plasma on the mineralization of human dental pulp cells in vivo.
Methods: DPCs were isolated from healthy dental pulp, and identified by immunostaining of vimentin and cytokeratin. PRP was obtained from healthy volunteer donors by traditional two-step centrifugation. The forth passage of DPCs and PRP were mixed well and activated, and then transplanted subcutaneously in 5-week female nude mice. The groups which were implanted with PRP alone or DPCs alone were used as controls. The animals were sacrificed after 4 weeks and 8 weeks post-transplantation, and the histological and immunohistostaining examinations were used to evaluate the effect of PRP on the mineralization of DPCs.
Results: Immunostaining showed that DPCs were positive for vimentin and negative for cytokeratin. In vivo assay showed that the newly formed mineralized tissues were only found in PRP combined with DPCs group after 4 weeks and 8 weeks, while newly formed tissues were not observed in PRP alone or DPCs alone groups. HE staining showed the mineralized tissues were found in PRP+DPCs samples. Immunohistochemistry staining showed these mineralized tissues were positive for osteopontin(OPN), osteocalcin(OC) and collagen I (COLI).
Conclusion: PRP had good biocompatibility with DPCs, and could induce the mineralization of DPCs. The study suggests that platelet-rich plasma can be used as a scaffold for pulp capping.