FIG 5.

Impact of inducible IFITM protein expression on IAV and PIV-3 infection of A549 cells. (A and B) A549 cells cultured for 24 hours in the absence (−DOX) or presence (+DOX) of doxycycline to induce IFITM expression were subsequently infected with IAV (MOI, 1) (A) or PIV-3 (MOI, 0.8) (B). (i) The percentage of virus-infected cells was determined by staining for IAV NP at 8 hpi or PIV-3 HN protein at 18 hpi, followed by flow cytometry. (***, P ≤ 0.001; **, P ≤ 0.01; *, P ≤ 0.05; ns, P > 0.05; unpaired, two-tailed t test). (ii) Fold change in the percentage of virus-infected cells in the presence or absence of each IFITM. (***, P ≤ 0.001; **, P ≤ 0.01; *, P ≤ 0.05; ns, P > 0.05; significance by one-way analysis of variance [ANOVA] with Tukey’s multiple comparative analysis). For IAV, data are representative of three independent experiments performed in triplicate. For PIV-3, data are pooled from four independent experiments performed in triplicate. Error bars represent the SEM. Control A549 cells express an irrelevant inducible protein.