Fig. 2
Characterization of BoHV-4-ΔIE1. a Representative images (phase contrast, fluorescence and merged; 10×) of BEK and BEK expressing cre (BEKcre; in the right panel) electroporated with pBAC-BoHV-4 and pBAC-BoHV-4ΔIE1 DNA. CPE induced by reconstitution of IRVPs is recognizable for all three BAC viral genomes (dark pictures in fluorescence for BAC transfected BEKcre cells is due the loss of GFP expression cassette contained in the floxed BAC backbone removed by cre recombinase). The test was repeated three times always giving identical results. b Replication kinetics of BoHV-4ΔIE1 (red line) and BoHV-4 (blue line). c Representative images (4× and 10×) showing plaque morphology and relative plaque sizes of BoHV-4 and BoHV-4ΔIE1 on Vero cells. d The plaque sizes (μm2) were measured using the Axio-Vision40-V4.6.3.0 (Carl Zeiss, Imaging Solution) software program. Bars represent means ± standard errors of 50 plaques for each virus [(**) P ≤ 0.001)]. Significance was measured by ANOVA