Effects of Platelet-released Supernatant on Mesenchymal Stem Cell Proliferation

Platelet-rich plasma (PRP), which is obtained by centrifuging autologous blood, contains a large number of platelets. When platelets are activated using substances such as thrombin, ƒ¿ granules release platelet released growth factor (PRGF) such as platelet-derived growth factor (PDGF) and transforming growth factor-ƒÀ (TGF-ƒÀ). Since these growth factors promote proliferation and differentiation of cells that are required for tissue regeneration, PRP has been used for bone and periodontal tissue regeneration in clinical dentistry. In the present study, we investigated the changes in PDGF-AB levels before and after platelet activation using ELISA. In addition, cellular proliferation was investigated by adding platelet released supernatant (PRS) produced by activating platelets of PRP to mesenchymal stem cell (MSC) culture media using MTS assay. The results showed that the level of PDGF-AB in PRS was 5.31 times higher than that before platelet activation. Furthermore, adding PRP or PRS significantly promoted MSC proliferation compared to the control, and adding PRS enhanced cellular proliferation in a dose-dependent manner from days 1 to 4 of culture. This study suggested that activation of platelets in PRP releases and concentrates PRGF, and that adding PRS to MSC promotes early cellular proliferation of MSC.