AmiRNAs expression plasmids inhibit specific H-PRRSV protein expression in MARC-145 cells. Cells seeded in 96-well (for indirect fluorescence assay, IFA) or 12-well (for Western blotting, WB) plates were transfected amiRNAs expression plasmids, and infected with H-PRRSV at 0.01 MOI at six-hour post-infection. At sixty hours after infection, PRRSV was detected by IFA and WB with PRRSV positive serum isolated from SPF pigs. Pictures were taken with an inverted fluorescence microscope. Magnification, 100×(A). Whole cell extracts of experimental groups were prepared for WB and β-actin protein was served as an internal reference (B). The data here was one represent of three experiments.