IRF-7, and NF-κB differentially determine expression of IL-28A/B and IL-29. Nucleotide sequence from 1.0 kb upstream of the transcription start site of human IL-28A, IL-28B, and IL-29. The positions of the IRF, NF-κB, AP-1, and GATA-1 binding sites are indicated. (B-D) PH5CH8 cells were transiently transfected with control plasmid pGL3-basic, and plasmids encoding luciferase constructs containing human IL-28A (pGL3-IL-28A 1kb) (B), IL-28B (pGL3-IL-28B 1kb) (C), or IL-29 (pGL3-IL-29 1kb) (D) promoter regions. Various mutation constructs of the above promoter regions were also transfected into PH5CH8 cells, using a Renilla luciferase vector as a control. The cells were cultured for 24 hours and then stimulated with poly(I:C) for 6 h or infected with JFH-1 for 12 h. Luciferase activity in whole cell lysates was normalized to Renilla luciferase activity. Data are the mean ± SD of triplicate data points from five independent experiments.