Figure 2.

RFP inhibited PRRSV proliferation in vitro. (A) Marc-145 cells were infected with PRRSV at an MOI of 0.1 for the indicated periods after RFP (150 μM) treatment. The mRNA levels of PRRSV-N were measured by qRT-PCR. GAPDH serves as a control. ^**p < 0.01; ^***p < 0.001. (B,C) Marc-145 cells or PAMs were infected with PRRSV and treated with RFP, at 24 hpi, the PRRSV N protein levels were measured by western blot. (D) Marc-145 cells were infected with PRRSV at an MOI of 0.1 and treated with RFP, at the indicated time, viral production in cells was measured and is shown as TCID50. ^**p < 0.01; ^***p < 0.001. (E) The same as (D) except that immunofluorescence was used. (F) Marc-145 cells were, respectively, infected with three successive generations of screened viruses after RFP treatment, and the protein levels of PRRSV N were measured by western blot.