Figure 6.

Poly(I:C) and IFN-β1 treatments down-regulate ERG, but not FLI1. HPAECs were treated with 2.5 μg/ml poly(I:C) (Toll-like receptor [TLR] 3) agonist or and IFN-β1 for indicated periods of time. (A and B) Relative mRNA expression was determined by quantitative RT-PCR. (C) Representative Western blot of HPAEC lysates treated with 2.5 μg/ml poly(I:C) or 1,000 U/ml IFN-β1 showing levels of FLI1 and ERG (n = 3 independent experiments). (D) HPEACs were pretreated with a TLR3/complex inhibitor (TLR3i; 50 μM) or IFN inhibitor, B18R (0.1 and 0.2 μg/ml) for 1 hour and then incubated with poly(I:C) or IFN-β1 for 24 hours. Chromatin immunoprecipitation followed by quantitative RT-PCR with primers targeting IFN-β1 promoter region (E) was performed on HPAECs treated for 6 hours with 2.5 μg/ml poly(I:C). (F) ERG or (G) signal transducers and activators of transcription (STAT) 1 antibodies were used. Data are presented as a percent of input DNA recovery. IgG, isotype control (n = 3 independent experiments). All data shown as mean (±SD). One-way ANOVA followed by Tukey’s multiple comparison were used for statistical analysis. *P < 0.05, ***P < 0.001.