Figure 5: Activation of osteoclast differentiation by IgG ICs through FcγRs.

(a) Effect of plate-bound IgG subclasses on osteoclast differentiation of WT, Fcgr2b^−/−, Fcgr3^−/−, Fcgr2b^−/−Fcer1g^−/− and Fcer1g^−/− cells co-cultured with WT osteoblasts. (b) PLCγ2 phosphorylation and NFATc1 induction in Fcgr2b^−/− cells in plate-bound IgG1-induced osteoclastogenesis. (c) Effect of retrovirus-mediated knockdown of FcγRIII expression on plate-bound IgG1-induced osteoclastogenesis of Fcgr2b^−/− cells. (d) Effect of knockdown of FcγRI or FcγRIV on plate-bound IgG2a-induced osteoclastogenesis of WT cells. All quantification experiments were performed using triplicate culture wells. All data are representative of more than three independent experiments and are shown as the mean±s.e.m. Statistical analyses were performed using unpaired two-tailed Student’s t-test (*P<0.05; **P<0.01; n.s., not significant).