Figure 2. TNF-{alpha} stimulates IL-6 secretion by MG-63 cells. (Panel A) Dose-response for 24-hour and 48-hour TNF-{alpha} stimulation. (Panel B) Secretion of IL-6 after pre-incubation with p38 MAPK inhibitor SB203580HCl for 1 hr prior to stimulation with TNF-{alpha} (20 ng/mL) for 24 hrs. *Statistically different from control (unstimulated) cultures (p < 0.05). Bars represent mean ± standard deviation (n = 4).