The pre-osteoblast murine cell line MC3T3-E1 was purchased from the Cell Resource Center of the Shanghai Institute of Biochemistry and Cell Biology at the Chinese Academy of Sciences, and cultured in alpha modified Eagle’s medium (α-MEM; Biological Industries, Israel) supplemented with 10% FBS (Biological Industries, Israel) and 1% (P/S). Cells were routinely subcultured using 0.05% trypsin/EDTA (Biological Industries, Israel) upon reaching 80–90% confluence.
The pre-osteoclast murine cell line Raw264.7 was purchased from the ATCC and cultured in Dulbecco’s modified Eagle medium (DMEM; Biological Industries, Israel), supplemented with 10% FBS (Biological Industries, Israel) and 1% P/S. After reaching 80–90% confluence, cells were routinely subcultured using 0.05% trypsin/EDTA (Biological Industries, Israel). All cells were maintained at 37°C in a humidified atmosphere of 5% CO2. Medium was changed every 2 days.