Fig. 4
BCP crystals activate MEK and ERK downstream of Syk/PI3K in primary macrophages and DC. a,b Human macrophages and c, d DC (2 × 106 cells/well) were stimulated with BCP crystals (50 μg/ml) for the indicated time points. Phosphorylation of MEK and ERK was detected by immunoblotting using phospho-specific antibodies. e,f Human macrophages and g,h DC were pre-treated with piceatannol (50 μM, 100 μM; lanes 3, 4), R788 (5 μM; lane 5), or LY294002 (50 μM; lane 6) for 30 min prior to stimulation with BCP crystals for 15 min. Phosphorylation of MEK and ERK was detected by immunoblotting. Representative blots of three independent experiments are shown. Densitometric analysis of three blots was performed using ImageJ software. Bar graphs illustrate the mean (± SEM) increase in phosphorylation, relative to the untreated sample (0) and normalised to total MEK/ERK protein. *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001