FIG 3.

In cellulo-evolved viruses with adaptive mutations display growth attenuation. (A and B) BHK-21 cells were infected at an MOI of 0.1 with WT SFV, with evolved stocks of (A) (SFV^CP2, SFV^SM) or (B) (SFV^CP) or with P₀ stocks of (A) (SFV^CP2+2A796V, SFV^SM+2V515E) or (B) (SFV^CP+2V2F, SFV^CP+2G460S, or SFV^CP+4R611K). At 0 h, 3 h, 6 h, 9 h, 12 h, 24 h, and 48 h p.i., the growth medium was collected, and the virus in the medium was titrated using a focus-forming assay. Each data point represents the mean ± SD from three independent experiments. The dotted line indicates the limit of detection.