Fig. 2. Inhibition of hMPV-induced interferon-β and chemokines gene transcription by expression of dominant negative RIG-I.
A549 cells were cotransfected with a luciferase reporter plasmid containing INF-β (A), RANTES (B) or IL-8 (C) promoter together with a RIG-I dominant negative mutant expression plasmid (RIG DN), or the corresponding empty vector (EV). Cells were infected with hMPV and harvested at 15 or 24 h p.i to measure luciferase activity. Uninfected plates served as controls. For each plate luciferase was normalized to the β-galactosidase reporter activity. Data are expressed as mean ± standard deviation of normalized luciferase activity. Bars represent the mean value of triplicate samples of one experiment, n = at least two experiments. *, P< 0.05 relative to hMPV-infected EV-treated cells.