Transcriptional activity at the IL-28A, IL-28B, and IL-29 promoter by HCV infection. PH5CH8 cells were transfected with a mixture of the luciferase constructs containing various 5' deletions of the human IL-28A (A), IL-28B (B), or IL-29 (C) promoters and Renilla luciferase control vector. The cells were cultured for 18 hours and then infected with JFH-1 for 12 hours. 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.