Gene-Specific Countermeasures against Ebola Virus Based on Antisense Phosphorodiamidate Morpholino Oligomers
Figure 1
Gene-Specific PMOs Inhibit Ebola Virus Gene Translation and Growth
(A) Schematic diagram of the EBOV genome showing the PMO sequences and the relative locations of their mRNA targets.
(B–D) Sequence-specific inhibition of EBOV VP24 (B), VP35 (C), and L (D) gene targets in cell-free translation assay. Plasmids containing 150 nucleotides encompassing the PMO target area from EBOV VP24, VP35, or L fused to firefly luciferase were used to generate RNA. Inhibition of the VP24, VP35, or L RNA targets was assessed using in vitro translation reactions containing different concentrations of PMO targeting EBOV (•) or MARV (▪) VP24, VP35, or L, respectively, or a scrambled (▴) PMO, along with the respective RNA. The data are shown as means of three replicates per data point and the standard error of the mean.
(E) Inhibition of viral amplification by PMOs in vitro. Vero E6 cells were pretreated for 24 h with 20 μM of EBOV VP24-specific PMO (blue), EBOV VP35-specific PMO (red), EBOV L-specific PMO (yellow), combination of the three EBOV-specific PMOs (gray), or a scrambled PMO (black). The cells were infected with EBOV-Zaire (multiplicity of infection = 1), and the viral titers were assessed at 24, 48, and 72 h post infection. The data are presented as percent reduction of EBOV-specific PMO-treated cells, as compared with the scrambled PMO-treated cells (titers at 24 h were 127 pfu/ml, at 48 h were 4,241 pfu/ml, and at 72 h were 202,000 pfu/ml). The experiments were performed at least three times and a single representative experiment is shown.