Fig. 1. Inhibition of osteoclast differentiation from BMMs and PBMCs by HA. (A,B) Effect of HA on osteoclastogenesis from BMMs. Mouse primary BMMs were cultured for 6 days with RANKL (100 ng/ml), M-CSF (30 ng/ml) and indicated concentrations of HA. After TRAP staining, TRAP⁺ multinuclear cells (TRAP⁺ MNCs) with more than three nuclei were scored as osteoclasts. ^*P<0.05 and ^**P<0.01 compared with vehicle-treated control. (C) No effects of HA on osteoclastic differentiation of RAW264.7 cells. Cells were cultured for 4 days with RANKL (100 ng/ml) and HA (0.1-5 µg/ml) and stained for TRAP, and TRAP⁺ MNCs were counted. (D) Effect of HA on human PBMC differentiation to osteoclasts. Human PBMCs were cultured for 9 days with RANKL (200 ng/ml), M-CSF (30 ng/ml) and indicated concentrations of HA. Cells were stained for TRAP and TRAP⁺ MNCs were counted. ^*P<0.05 and ^**P<0.01 compared with vehicle-treated control.