Figure 2

SADS-CoV suppresses poly(I:C)-induced IFN-λ1 production. A IFN-λ1 mRNA expression in SADS-CoV-infected cells. IPI-FX cells were either mock-infected or infected with SADS-CoV at a MOI of 1. The mRNA level of the IFN-λ1 gene was measured at the indicated hours post-infection using RT-qPCR. Mock-infected cells stimulated with 1 μg/mL poly(I:C) for 12 h were used as the positive control. B SADS-CoV suppresses poly(I:C)-induced IFN-λ1 promoter activity. IPI-FX cells were co-transfected with IFN-λ1-luc and pRL-TK at a ratio of 1:0.1 for 12 h. Then, cells were either mock-infected or infected with SADS-CoV at a MOI of 1 for 12 h. Subsequently, cells were transfected with or without poly(I:C) for an additional 12 h, and the relative activity of the IFN-λ1 promoter was determined using a luciferase reporter assay. C–E SADS-CoV suppresses poly(I:C)-induced IFN-λ1 (C), IFN-λ3 (D), and IFN-λ4 (E) mRNA levels. IPI-FX cells were infected or mock-infected with SADS-CoV at a MOI of 1 for 12 h and then transfected with or without 1 μg/mL poly(I:C) for an additional 12 h. Total RNA was extracted, and the relative mRNA expression of IFN-λ1, IFN-λ3, and IFN-λ4 was determined using RT-qPCR. Data are represented as the mean ± SD of three replicates. ***P < 0.001.