Fig. 4. Therapeutic oral efficacy of 4′-FlU in the RSV mouse model.

(A) Balb/cJ mice were inoculated with recRSV-A2line19F-[mKate] and treated as indicated. At 4.5 days after infection, viral lung titers were determined with TCID₅₀ titration (n = 5). (B) Balb/cJ mice were inoculated with recRSV-A2line19F-[mKate] or mock-infected, and treated as indicated. Blood samples were collected before infection and at 1.5, 2.5, 3.5, and 4.5 days after infection, and lymphocyte proportions with platelets/ml are represented over time (n = 4). (C) Balb/cJ mice were inoculated with recRSV-A2line19F-[redFirefly] and treated as indicated. In vivo luciferase activity was measured daily. (D) Total photon flux from mice lungs from (C) over time (n = 3). (E) Balb/cJ mice were inoculated with recRSV-A2line19F-[mKate] and treated as indicated. At 4.5 days after infection, viral lung titers were determined with TCID₅₀ titration (n = 5). In all panels, symbols represent individual values, and bars or lines represent means. One-way ordinary analysis of variance (ANOVA) with Tukey’s post hoc multiple comparisons (B) and (I) or two-way ANOVA with Dunnett’s post hoc multiple comparison (C) and (G). h.p.i., hours post-infection.