Figure 6.

OSM, but not LIF, stimulates osteoclastogenesis in bone marrow cell cultures. Mouse bone marrow cells (BMC) were cultured in the absence (Co) or the presence of LIF, or OSM (both at 100 ng/mL), PTH or 1,25(OH)₂-vitamin D3 (D3; both at 10⁻⁸ M) for 7 days before staining (A) and counting (B) of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated osteoclasts (TRAP⁺MuOCL). Quantitative real-time PCR analysis of mRNA expression of cathepsin K (Ctsk, C), TRAP (Acp5, D), calcitonin receptor (Calcr, E) RANKL (Tnfsf11, F) and OPG (Tnfsf11b, G) in BMC cultured without (Co) or with LIF or OSM (both at 100 ng/mL) for 7 days. Values represent means for four wells and SEM is shown as vertical bars. ^***, indicates significant difference compared to untreated (Co) cells, ^***P < 0.001. Statistical significance was determined by ANOVA using Levene's homogeneity test followed by Dunnett's 2-sided (B–F) or Dunnett's T3 (G) post-hoc test.