Abstract: PURPOSE: To observe the effect of concentrated growth factor(CGF) on the biological properties of osteoblasts. METHODS: MC3T3-E1 cells were cultured in CGF environment and a blank control group was established. The adhesion of osteoblasts to CGF surface was observed by scanning electron microscopy. Cell proliferation and alkaline phosphatase(ALP) activity were detected at 1, 4 and 7 d by Cell Counting Kit-8 (CCK-8) and Alkaline Phosphatase Assay Kit. The expression of mineralized nodules and osteogenesis-related gene Runx2 was observed by alizarin red staining. CGF extract was cultured for 24 h. Peptide staining was used to observe morphological changes in the cytoskeleton. SPSS 21.0 software package was used for statistical analysis. RESULTS: CCK-8 showed cells incubated for 1, 4 and 7 d in the experimental group had a stronger proliferation ability compared with the control group, and the difference was statistically significant (P<0.05). ALP activity test showed that there was no significant difference between the experimental group and the control group (P>0.05) at 1 d; but after 4 days of culture, cell in the experimental group had an increased ALP activity compared with the control group, and the difference was statistically significant(P<0.05). The results of alizarin red staining showed that the number of calcified nodules in the CGF group increased and the area was larger. In the phalloidin staining and DAPI staining, the number of cells in the CGF group increased, the cell spreading surface increased, and the actin shape was clearer. CGF significantly promoted Runx2 mRNA expression(P<0.05). CONCLUSIONS: High concentration of CGF can promote the proliferation and differentiation of MC3T3-E1 cells and the expression level of related osteogenic gene Runx2.

Key words: Concentrated growth factors, MC3T3-E1, Proliferation, Differentiation