Fig. 3.

Effect of TNF-α on migratory response of BM-MSC to TRAIL. a Migration capacity of unstimulated and TNF-α-stimulated BM-MSC toward recombinant TRAIL, used at the indicated concentrations, was evaluated in Transwell plates as described in the Methods. *P < 0.05 with respect to untreated cultures (without cytokines); **P < 0.05 with respect to the corresponding unstimulated culture exposed to the same TRAIL concentration. b Effects of recombinant OPG on BM-MSC migration driven by TRAIL. After plating BM-MSC in the upper compartment of Transwell plates, soluble recombinant TRAIL (100 pg/ml) was used either alone (w/o pre-incubation) or after pre-incubation with OPG (TRAIL + OPG), used at the indicated OPG:TRAIL ratios, in the absence or presence of neutralizing anti-OPG Ab. *P < 0.05 with respect to cells treated with TRAIL in the absence of OPG. In a and b, data are the mean ± SD of results from at least three independent experiments, each performed in duplicate