Figure 4.

The cGas–Sting–Tbk1–Irf3 pathway contributes to the induction of IFN-β in RAW264.7 cells by ectromelia virus (ECTV). cGas^−/− (A), Sting^−/− (B), Irf3^−/− (C), and Tbk1^−/− (D) RAW264.7 and wild-type (WT) cells were infected with ECTV at an MOI of 5. Supernatants were collected 18 h post-infection (hpi) for determining the concentrations of IFN-β by using enzyme-linked immunosorbent assay (ELISA), and cells were collected at 15 and 18 hpi for western blot analysis using anti-phospho-Tbk1, anti-Tbk1, anti-phospho-Irf3, and anti-Irf3. β-Actin was used as a loading control. The ELISA data are averaged from three independent experiments in biological triplicate. Results of western blot analysis shown are representative of three independent experiments. The data were analyzed using a t-test on SPSS software (**P ≤ 0.01 and ***P ≤ 0.001).