Fig. 7: Inability of MARV to antagonize IFN-I signaling partially contributes to attenuated replication.
From: Jamaican fruit bats’ competence for Ebola but not Marburg virus is driven by intrinsic differences
A Schematic mechanisms of EBOV VP24 and MARV VP40 antagonism of the type-I interferon signaling pathway. Image created in BioRender [https://BioRender.com/b428467]. B Immunoblot of cytoplasmic and nuclear fractions of Jamaican fruit bat kidney cells, AjKi_RML2, infected with MOI 1.5 of EBOV-Mayinga or MARV-Ozolin for 24 h prior to the addition of recombinant Chiroptera IFN-β. The presented panel is representative of three independent immunoblots. C Quantification of phosphorylated STAT1 in the cytoplasmic and nuclear fractions. Three independent experiments were performed. Percentage of pSTAT1 in each of the fractions for EBOV and MARV-infected cells was compared mock using a two-way ANOVA with Dunnett’s multiple test comparison. Data plotted as mean ± S.D. P values for comparisons to mock are indicated. **** < 0.001, * < 0.05. D AjKi_RML2 cells were infected with MOI 0.1 EBOV-Mayinga or MARV-Ozolin for with vehicle control DMSO or itacitinib immediately after infection. The experiment was performed in triplicate. The effect of itacitinb on EBOV and MARV replication was determined using a one-way ANOVA with Dunnett’s multiple test comparison. Data plotted as mean ± S.D. P values for comparisons to mock are indicated. * < 0.05. E Immunoblot showing the effect of itacitinib treatment on the activation of the immune response and VP40 expression. F Quantification of VP40 for the immunoblot presented in (D). The effect of itacitinb on EBOV and MARV VP40 expression was determined using a one-way ANOVA with Dunnett’s multiple test comparison. The data is from three independent western blots. Data plotted as mean ± S.D. G Infectious titers of EBOV-Mayinga or MARV-Ozolin at 48 h post-infection. AjKi_RML2 cells were treated with recombinant Chiroptera IFN-β in 10-fold serial dilution for 24 h prior to infection with MOI 0.1. Data presented as log10 transformed values. The experiment was performed in triplicate. To test a change in viral titer at each dose compared to mock treated cells, we performed a two-way ANOVA with Dunnett’s multiple test comparison. Data plotted as mean ± S.D. P values for comparisons to mock are indicated. **** <0.001, * <0.05.
