Replication of BHV-4 directs the expression of core 2 branched oligosaccharides in infected cells. Subconfluent monolayers of EBTr cells were transfected with pcDSRα-leukosialin by using FuGENE 6 transfection reagent. Twenty-four hours after transfection, the cells were mock infected (A, C, and E) or infected (B, D, and F) with BHV-4 at a multiplicity of infection of 10. Twenty-four hours after infection, the cells were treated for indirect immunofluorescent staining of fixed and permeabilized samples. mAb 1G10 reacting with leukosialin (A and B), mAb 35 reacting with BHV-4 glycoprotein complex gp6/gp10/gp17 (C and D), and mAb T305 raised against leukosialin expressing core 2 oligosaccharides (E and F) were used as primary Abs and were revealed by Alexa-GAM Abs. The percentage of positive cells estimated by examination of 600 randomly selected cells is presented in each panel. (Bar, 10 μm.)