Fig. 1.

Suppression of type I IFN production in LLC-PK cells by PEDV. (A), Expression of N protein in PEDV-infected cells. Cells were infected with PEDV at an MOI of 0.01 for 24 h, and Western blot was conducted using anti-N mAb. (B) and (C), Suppression of type I IFN production by PEDV. LLC-PK1 cells were grown in 12-well plates and infected with PEDV either at a low MOI (0.01 MOI, panel B) or a high MOI (5 MOI, panel C). Cells were harvested at indicated times, and expressions of IFN-α and IFN-β were determined by RT-qPCR. Cells stimulated with poly(I:C) for 12 h were used as positive controls. (D) and (E), Stimulation for type I IFN production by poly(I:C) and suppression by PEDV. LLC-PK1 cells were infected with PEDV at an MOI of 0.01 for 12 h, and stimulated with poly(I:C) for 12 h. Cells were harvested and expression of IFN-α (D) and IFN-β (E) were determined by RT-qPCR. Asterisks indicate statistical significance calculated by the Student's t-test. *, P<0.05; **, P<0.01; ***, P<0.001.