Fig. 4

Fibroblast priming is transient. a Fibroblast-like synovioctyes (FLS) were stimulated (stim) with TNFα or IL-1α (both 10 ng/mL) for 24 h, washed and rested for one, three or seven days, then washed and stimulated again for 24 h. Responses to the first and second dose were analysed by IL-6 ELISA, and response to the second dose was represented as a fold change from response to first dose (normalised to one). Mean ± SEM, n = 5–10. *p < 0.05, **p < 0.01 (Wilcoxon matched pairs signed rank test); n.s. not significant b BJ fibroblasts were treated with vehicle or TNFα for 24 h then washed and rested in fresh medium for one, two or three days. Whole cell lysates were prepared, and phosphorylated forms of signalling molecules were detected by western blotting. c Phospho-RelA was quantified in three independent experiments, normalized against the loading control tubulin and plotted relative to the level in unstimulated cells