Figure 8
OPG-resistant differentiation of Opto-RANKc cells. (a-b) RAW264.7 cells were cultured in RANK-containing medium in the absence (a) and presence (b) of OPG. Cells were stained for TRAP and representative images are shown. OPG inhibited the RANKL-induced differentiation of RAW264.7 cells. Scale bar: 150 μm. (c-d) Opto-RANKc cells were cultured on CaP-coated 96-well plates in the absence (c) and presence (d) of OPG, with blue light exposure every 2 min, for 13 d, without passage. Representative images of pit-formation from six independent experiments. Scale bar: 2 mm. (e) Measurement of the pit area in (c) and (d). The data show the area of the pits as a percentage of the area of the entire well, represented as mean ± SD values from six independent experiments. Data were analyzed using two-tailed unpaired t-test. ns, not significant. RANK, receptor activator of nuclear factor-kB; TRAP, tartrate-resistant acid phosphatase; OPG, osteoprotegerin; CaP, calcium phosphate.
