FIG 6 .

Effect of doxorubicin in vitro. (A) The toxicity of doxorubicin was evaluated in A549 cells using the CellTiter-Glo assay at 48 h after treatment with the drug. (B) Titers of an Ebola virus that expresses GFP (EBOV) after infection at a multiplicity of 2 of A549 cells in the presence of DMSO or doxorubicin (10 μM) (Doxo). The cells were pretreated with doxorubicin prior to infection for 1 h, and doxorubicin was added back to the medium after the infection. The error bars indicate the standard deviations from three independent replicates. **, P value < 0.01 (Student’s two-tailed t test). Data represent means ± standard deviations from two independent experiments (each performed in triplicate). (C and D) qRT-PCR for endogenous IFN-β (C) and ISG54 (D) mRNA levels normalized to β-actin mRNA at indicated postinfection time points. The error bars indicate the standard deviations from three independent replicates. ***, P value < 0.001; ****, P value < 0.0001 (Student’s two-tailed t test). hpi, hours postinfection.