TWEAK/Fn14 interaction induces RANTES production by MC3T3-E1 cells. (a) MC3T3-E1 cells were cultured in the presence or absence of 100 ng/ml TWEAK for 48 hours. The culture supernatants were then collected and subjected to a cytokine protein array. The table indicates the corresponding cytokines on the protein array membrane. (b) MC3T3-E1 cells were stimulated with the indicated doses of TWEAK for 48 hours in the presence or absence of the indicated doses (ng/ml) of mouse Fn14-Fc chimera or control mouse immunoglobulin G (mIgG). The culture supernatants were then collected, and the RANTES concentrations were measured by enzyme-linked immunosorbent assay. (c) MC3T3-E1 cells were stimulated with the indicated doses of TWEAK for 96 hours. Viable cell number was then measured by WST assay. The data were expressed as OD units. Values represent the mean ± standard deviation. *p < 0.05 compared with corresponding control. Similar results were obtained in at least three independent experiments. Fn14, fibroblast growth factor-inducible 14; G-CSF, granulocyte-cell-stimulating factor; GM-CSF, granulocyte macrophage-colony-stimulating factor; IFN-γ, interferon-γ; IL, interleukin; IP-10, inositol phosphate-10; M-CSF, macrophage-colony-stimulating factor; MIG, monokine induced by IFN-γ; MIP-1α, viral macrophage inflammatory protein-1α; OD, optical density; RANTES, regulated upon activation, healthy T cell expressed and secreted; TNF-α, tumour necrosis factor-α; TWEAK, tumour necrosis factor-like weak inducer of apoptosis; VEGF, vascular endothelial growth factor; WST, water-soluble tetrazolium.