Fig. 4.

Andro and PDS suppress PRRSV replication in co- and post-treatment modes. Marc-145 cells were grown in 24-well plates for 24 h and then treated with Andro (45 μmol/L) or PDS (560 μmol/L) for 2–8 h prior to virus infection (pre-treatment), for 2 h during viral infection (co-treatment), or for 2–8 h after virus infection and removal (post-treatment) (A). For all three treatment modes, 0.05 MOI of PRRSV GD-HD was used to infect the cells for 2 h. At 24 hpi, the cells were subjected to viral N protein analysis using IFA (B). The percentages of inhibition based on the fluorescence optical densities (OD) of the images from three independent experiments are shown in C. Scale bar: 250 µm. *P < 0.05, **P < 0.01, and ***P < 0.001 compared to the DMSO-treated control.