The in vitro effect of different PRP concentrations on osteoblasts and fibroblasts.

OBJECTIVES: The aim of this study was to assess the biological rationale for the use of platelet-rich plasma (PRP) by evaluating the effect of different concentrations of PRP on osteoblasts (OB) and fibroblasts (FB) function in vitro.

MATERIAL AND METHODS: PRP was obtained from volunteer donors using standard protocols. Primary human cultures of oral FBs and OBs were exposed to both activated and non-activated plasma as well as various concentrations of PRP (2.5 x, 3.5 x and max (4.2-5.5 x)). Cell proliferation was evaluated after 24 and 72 h using an MTT proliferation assay. Production of osteocalcin (OCN), osteoprotegerin (OPG) and transforming growth factor beta1 (TGF-beta1) was evaluated in OB after 24 and 72 h. Statistical analysis was performed using one-way ANOVA.

RESULTS: PRP-stimulated cell proliferation in both OBs and FBs. The effect of different PRP concentrations on cell proliferation was most notable at 72 h. The maximum effect was achieved with a concentration of 2.5 x, with higher concentrations resulting in a reduction of cell proliferation. Upregulation of OCN levels and downregulation of OPG levels were noted with increasing PRP concentrations at both 24 and 72 h. TGF-beta1 levels were stimulated by increasing concentrations of PRP, with the increased levels being maintained at 72 h.

CONCLUSIONS: PRP preparations exert a dose-specific effect on oral FBs and OBs. Optimal results were observed at a platelet concentration of 2.5 x, which was approximately half of the maximal concentrate that could be obtained. Increased concentrations resulted in a reduction in proliferation and a suboptimal effect on OB function. Hence, different PRP concentrations may have an impact on the results that can be obtained in vivo.