Fig. 3.
Increased osteoclastogenesis in vitro after co-culturing mouse haematopoietic pre-osteoclasts with ARCaPM or ARCaPE-Snail transfectants. (a) Top panels: RANKL induced osteoclastogenesis in haematopoietic pre-osteoclastic precursor cells was blocked by OPG. Bottom panels: ARCaPM cells that overexpress RANKL when co-cultured with mouse haematopoietic pre-osteoclasts induced more TRAP positive staining cells, an indication of inducing osteoclast maturation, as seen under light microscopy, compared to ARCaPE co-culture. This increased osteoclastogenesis was effectively antagonized by osteoprotegerin (OPG), suggesting that the RANKL overexpressed by ARCaPM cells is functional (200×). Inset, multi-nucleated osteoclast at 400×. (b) Multinucleated TRAP positive cells from ARCaPE, ARCaPM, or ARCaPE-Snail 12 clone co-culture were counted and quantified. Overexpression of Snail induced marked TRAP positive cells indicative of functional RANKL which was blocked by OPG. Data represent triplicates obtained from 2 independent experiments