The Effect of Different Concentrations of Platelet-Rich Plasma on Human Periodontal Ligament Cells In Vitro

Purpose: To assess the effect of different concentrations of platelet-rich plasma (PRP) on cell proliferation and alkaline phosphatase (ALP) activity of human periodontal ligament cells (hPDLCs) in vitro.

Methods: PRP was obtained from volunteer donors using two-step centrifugation. TGF-beta1 and PDGF-AB levels in activated PRP, PRP and plasma were evaluated by enzyme-linked immunosorbent assay. hPDLCs were exposed to various concentrations of PRP (2%,5%,10% and 20%) and DMEM (negative control), respectively. After 24 and 72 hours, cell proliferation was evaluated using Cell Counting Kit-8 assay. Alkaline phosphatase (ALP) activity of hPDLCs was evaluated by a p-nitrophenyl phosphate disodium assay. Statistical analysis was performed using one-way ANOVA and Student’s t test in SPSS10.0.

Results: TGF-beta1 and PDGF-AB levels were highest in activated PRP. The effect of various concentrations of PRP on cell proliferation and ALP activity was significantly greater than that of negative control (P<0.001). The effect of PRP was significantly greater at 72-hour compared with that at 24-hour (P<0.01), with significantly difference among various PRP concentrations (P<0.001). Cell proliferation and ALP activity increased when the concentration of PRP increased from 2% to 10%. The maximum effect on cell proliferation was achieved with 10% PRP; 20% PRP resulted in a reduced cell proliferation. However, ALP activity was greatest with 20% PRP.

Conclusion: PRP preparations exert a dose-dependent effect on hPDLCs proliferation and ALP activity in a certain extent in vitro at 24-hour and 72-hour.