Characterization of Bone Cells Obtained from the Calvaria of Neonatal Rats (osteo-1) after Serial Subculture

The objective of the present study was to characterize bone cells grown in two culture media, and to determine the effective concentration of OP-1 on the growth of osteo-1 cells. Subcultured rat bone cells (osteo-1) were grown in alpha-modified Eagle's minimal essential medium (alpha-MEM) and Dulbecco's modified Eagle's medium (DMEM) and total protein content, alkaline phosphatase activity and the formation of mineralized nodules were evaluated after 7, 14 and 21 days. Cells were exposed to different concentrations of rhOP-1 for 1, 3, 5 and 7 days and compared with an untreated control. Osteo-1 cells presented a significant increase in alkaline phosphatase activity and calcium deposits were observed at 21 days. Cells treated with 10 and 20 ng/mL rhOP-1 for 24 h showed a significant increase in cell viability when compared to control. Osteo-1 cells cultured on DMEM demonstrated an osteoblastic phenotype as indicated by high alkaline phosphatase activity and the presence of calcified nodules. The results suggest that low concentrations of OP-1 may promote an osteogenic effect on osteo-1 cells.