Characterization of growth properties of vBRf, vBR in comparison to wild-type virus CPXV.BR. A. Vero cells were infected at the indicated MOI (0.01 or 3) with the various viruses, and virus titers were determined from culture supernatants or the infected-cell pellets at the time points given. Shown are means of two independent experiments and the standard deviations (error bars). B. Plaque areas were determined by measuring a total of 40 plaques induced by each virus at 72 h pi. Plaques were stained with crystal violet and plaque images were taken using the Axiovert 25 microscope and CCD camera (Zeiss). Plaque sizes were measured using ImageJ. Mean plaque sizes induced by CPXV.BR were calculated and set to a 100%. Plaque areas determined for vBRf or vBR are shown relative to the CPXV.BR value. Shown are means and standard deviations (error bars) for each virus. C. End point titers were determined after infection of Vero cells with the indicated viruses at an MOI of 0.01, 0.1 or 3. Virus titers were determined from whole cell lysates at 24, 48 or 72 h pi.