De novo synthesis-independent inhibitory activity of STA-5326 on IL-12 production. STA-5326 was added together with SAC to the culture of IFN-γ–primed human PBMCs in the presence (⋄) or absence (♦) of 5 μg/mL CHX. IL-10 was added 1 hour prior to SAC. Percentage of inhibition was calculated from the corresponding control. Results are shown as mean ± SD of 1 representative of 3 individual experiments.