Figure 5.

Stimulus-independent role for DHX9 in IL-6 production in human cells. A, BEAS-2B cells were transduced with lentiviruses encoding DHX9-targeting shRNA (A7 or D11) or a NSC shRNA. After puromycin selection, the cells were incubated with 1 μg/ml of doxycycline for 72 h to induce the required shRNA. Lysates were generated and immunoblotted with anti-DHX9 and anti-tubulin antibody. B, BEAS-2B cells expressing doxycycline-inducible shRNAs were incubated with 1 μg/ml of doxycycline for 72 h and then stimulated with medium, 10 μg/ml of Pam₃CSK₄ (PAM3), 100 ng/ml of IL-1, 12.5 μg/ml of poly(I:C), or transfected (TF) with Lipofectamine only (Lipo only), 25 μg/ml of poly(I:C) or 1 μg/ml of poly(dA:dT) for 24 h. Supernatants were removed and IL-6 secretion was measured by ELISA. C, HeLa cells were transfected with empty vector (EV), 50 ng of MyD88 or 25, 50, or 100 ng of DHX9 expression vector (wedge) as indicated. Supernatants were removed 48 h after transfection and analyzed for IL-6. Data are mean ± S.D. of triplicate samples and is representative of three (B) or two (C) experiments. *, p < 0.05; **, p < 0.01; ***, p < 0.001; ****, p < 0.0001.