Distribution of IFITMs in CSFV-infected PAMs. (A) Confirmation of C1-IFITM1, C1-IFITM2, and C1-IFITM3 transfection in PAMs by western blot detection of fusion proteins with an anti-GFP antibody. PAMs were transfected with C1-IFITM1, C1-IFITM2, C1-IFITM3, or C1-EGFP for 48 h and collected for western blot analysis. β-actin served as an internal control. (B) Confocal images of PAMs expressing EGFP-tagged IFITM1, 2, or 3 or EGFP alone. PAMs were transfected with C1-EGFP (a), C1-IFITM1 (b), C1-IFITM2 (c), or C1-IFITM3 (d) for 24 h, followed by mock infection or infection with CSFV (MOI = 1) for another 24 h. Cells were fixed and stained with 4′,6-diamidino-2-phenylindole (DAPI, blue). Scale bars, 10 μm.