Figure 6From: TWEAK and Fn14 expression in the pathogenesis of joint inflammation and bone erosion in rheumatoid arthritisEffect of soluble TWEAK on osteoclast formation and function. Human unfractionated PBMC were cultured for nine days in medium containing rhM-CSF only (25 ng/ml) (A), M-CSF and rhTWEAK at 100 ng/ml (B), 400 ng/ml (C) or 800 ng/ml (D), M-CSF and rhRANKL (50 ng/ml) (E), or all of M-CSF (25 ng/ml), RANKL (50 ng/ml) and TWEAK (100 ng/ml) (F). Cultures were then fixed and stained for TRAP. (G) Multinucleated cells (MNC), containing >3 nuclei, positive for TRAP, were counted from quadruplicate wells. Data are expressed as means ± standard deviation. Significant differences were determined by one way analysis of variance (ANOVA) with Tukey post-hoc test: a indicates difference to M-CSF only control (P < 0.001) and b denotes difference to M-CSF+RANKL treatment (P < 0.05). (H) PBMC were seeded onto dentine slices in the presence of rhM-CSF (25 ng/ml) with the addition of rhRANKL (50 ng/ml) and/or rhTWEAK as indicated. Resorption was assessed after 14 days of culture by SEM and is expressed as the mean ± SD resorption expressed as a percentage of that measured for the RANKL/M-CSF control. Data shown are pooled from two independent experiments with resorption assessed for four dentine slices/treatment/donor. No significant differences were observed between RANKL treatments.Back to article page