Osteoclast and Osteoblast Cell Culture

The hBMSCs were purchased from the American Type Culture Collection (ATCC, Manassas, VA, USA). The hBMSCs were maintained in low-glucose Dulbecco’s modified Eagle’s medium (DMEM-LG; Gibco BRL, Rockville, MD, USA) with 10% fetal bovine serum (FBS; Gibco) and 1% penicillin and streptomycin (P/S, Gibco). The BMMs were isolated from C57BL/6 mice (8-week-old) by flushing the bone marrow of the tibiae and femurs. The BMMs were cultured in α-MEM (Gibco) containing 10% FBS, 1% P/S, and 30 ng/mL M-CSF (416-ML/CF, R&D Systems, Minneapolis, MN, USA) for 3 days. Subsequently, adherent cells were used as the osteoclast precursor cells^{40 (link)}. The RAW 264.7 cells were obtained from Korean Cell Line Bank (Seoul, Korea) and were cultured with α-MEM (Gibco) containing 10% FBS and 1% P/S. MC3T3-E1 (mouse pre-osteoblasts) cells were purchased from ATCC and maintained in alpha-modified minimum essential medium (Alpha-MEM, Gibco) supplemented with 10% FBS (Gibco) and 1% PS (Gibco). 3′-SL was provided by GeneChem Inc. (Daejeon, Korea).