IL-22 stimulates cytokine production and ERK phosphorylation in 3T3-L1 adipocytes.

<p>(A) IL-22 receptors are expressed in differentiated 3T3-L1 cells. The mRNA levels of IL-22R1 and IL-10R2 were analyzed by RT-PCR. GAPDH was used as a loading control. The cells were treated with recombinant IL-22 (500 ng/ml) for 24 hours as indicated. (B) The expression of IL-1β and IL-10 were increased by IL-22 treatment. Differentiated 3T3-L1 cells were treated with recombinant IL-22 (500 ng/ml) for 24 hours and the total RNA was isolated and used in real-time quantitative RT-PCR to detect the expression levels of IL-1β, IL-10, INF-γ, TNF-α, and IL-6. The data are shown as mean ± SD (n = 3 for each group). ** indicates p<0.01 between the control and IL-22-treated groups. (C) Stimulation of ERK phosphorylation by IL-22 in 3T3-L1 cells. The cells were treated with recombinant IL-22 (500 ng/ml) for the length of time as indicated and the cell lysate was used in immunoblotting.