Fig. 8

Decreased viral replication in NIH-3T3 cells transfected with the P2 and/or P3 genes. a Selection of NIH-3T3 cell lines expressing the P2, P3, and P2/P3 genes. Retroviruses containing the P2, P3, and P2/P3 genes were produced in Phoenix cells using the pMIG retroviral vector. NIH-3T3 cells were infected with the recombinant retroviruses. After a 2-week rest period, GFP-positive cells with MFI intensity between 3000 and 7500 were sorted with Moflo. Uninfected 3T3 cells (clear histogram) were compared with 3T3 cells infected with retroviruses containing the viral genes (shaded histogram). b Infectious virus levels produced 48 h post-infection with TMEV (MOI = 10) were compared by standard plaque assay using BHK-21. pMIG and 3T3 cells infected with retrovirus containing empty vector; P2, pMIG-P2; P3, pMIG-P3; P2/P3, pMIG-P2/P3; and 3T3, untransfected NIH-3T3 cells. c Expression of viral, IFN-α, and IFN-β messages was assessed by real-time PCR at 6, 12, 18, and 24 h post-infection. Values given are the means (±SD) of the results from triplicate wells. *P < 0.05; **P < 0.01