Figure 1.

LX-induced SOCS2 physically interacts with TRAF2 and TRAF6, inhibiting proinflammatory cytokine expression by DCs. (A) Splenic DCs were incubated with 1 μg/ml LXA₄ or 100 ng/ml IL-10 or media control (CT) for 6 or 12 h. SOCS2 or SOCS1 was immunoprecipitated (I.P.) from whole-cell lysates, followed by Western blot analysis of immunoprecipitates and total cell lysates to quantify SOCS1, SOCS2, TRAF1-6, IRAK4, MyD88, and actin expression. (B) DCs from WT or SOCS2-deficient mice were exposed to 1 μg/ml LXA₄ or vehicle for 6 h, followed by stimulation with IL-1β, TNF (both at 100 ng/ml), CD40L, STAg, LPS, or CpG-oligonucleotides (all at 1 μg/ml). 4 h later, mRNA was purified and real-time RT-PCR was used to quantify TNF, IL-6, IL-12p40, and IFN-α mRNA expression. Data shown are the mean (± the SD) of triplicate samples, and are representative of at least two independent experiments with similar results. Asterisks indicate statistically significant differences between SOCS2-deficient and WT control mice (P < 0.05).