Research Paper Volume 14, Issue 1 pp 253—271
Increased expression of osteopontin in subchondral bone promotes bone turnover and remodeling, and accelerates the progression of OA in a mouse model
Figure 3. OPN promotes osteoclastogenesis in the subchondral bone in OA. (A) TRAP staining and quantitative analysis of osteoclasts in the tibial subchondral bone of an OA mouse model treated with vehicle, rmOPN or neutralizing antibody, and sham group. Positive cells were indicated with arrows; scale bars = 50 μm, n = 6. (B) TRAP staining of BMMs treated with M-CSF (20 ng/ml) and RANKL (50 ng/ml) followed by the stimulation with rmOPN (100 ng/mL) and antibody (1.0 μg/mL) for 5 or 7 days. Positive cells were indicated with arrows. TRAP-positive multinuclear cells containing more than three nuclei were counted as osteoclasts; scale bars = 50 μm, n = 6. (C) Western blot analysis of the expression of RANKL in BMMs treated with M-CSF and RANKL followed by the stimulation with rmOPN (100 ng/mL) and antibody (1.0 μg/mL) for 5 or 7 days. Data are shown as mean ± s. d and were analyzed by one-way ANOVA; *P < 0.05, **P < 0.01.