OBJECTIVETo assess the effect of platelet rich plasma (PRP) on proliferation and differentiation of human MG63 osteoblast-like cells and the biological function of PRP in vitro.

METHODSPRP was obtained from venous blood of a health volunteer by two step centrifugation. CaCl2 and thrombin were used to activate PRP. The differentiation of MG63 cells, which were exposed to various concentrations of PRP (0, 1%, 2%, 3%) was detected by alkaline phosphatase (ALP) activity. Propidium iodide (PI) fluorescent coloration staining was used to observe the morphology of cells. Immunocytochemistry was used to evaluate the expression level of transforming growth factor-beta (TGF-beta) in MG63 cells in different concentration of PRP. The cells adhered to calcium phosphate material was observed by scanning electron microscopy (SEM). The proliferation was evaluated by cell counting kit-8 (CCK-8) proliferation assay. The cell cycle assay was performed by low cytometry (FCM) to detect the effect of PRP on MG63 cells in different time points. The mRNA level of Col-I in MG63 cells cultured under different concentration PRP was checked by reverse transcription polymerase chain reaction (RT-PCR).

RESULTSALP activity experiment demonstrated that the maximum effect was got in 3% PRP group. PRP had a positive effect on the proliferation of MG63 cells but cells also presented disengage phenomena from the glass slides. The PI staining showed that PRP improved fluorescent intensity of cell nucleus. Immunocytochemistry showed that TGF-beta expression level was significantly enhanced on 3% PRP group (P<0.05). SEM showed that cells grew well on material in PRP group. The results of CCK-8 showed that the mean absorbency number A(450 nm) of 4.8% PRP was significantly higher than that of control group (P<0.05). FCM showed that S period cells percentage of PRP group was higher than that of control group in the 2nd day (P<0.05); G0/G1 period cells percentage of PRP group was significant increased than that of control group in the 10th day (P<0.05); G2/M period cells percentage of PRP group was higher than that of control group except the 6th day. PRP promoted the expression of Col- I in MG63 cells by RT-PCR.

CONCLUSIONThese data suggest that PRP has a positive influence on MG63 proliferation, transference and the expression of relative protein and gene in an appropriated concentration. The findings of this study also demonstrated that PRP may play a beneficial role of unifying and modulating the biological behavior of MG63 cells.