Intracellular localization of DEV pUL55 in DEV-infected cells at 60 h, 70 h and 74 h post-infection. M-O. DEV-infected cells were fixed at 60 h, 70 h and 74 h post-infection. Samples were incubated with anti-pUL55 serum and subsequently stained with fluorescein isothiocyanate(FITC)-conjugated secondary antibody. Nuclei were counterstained with DAPI(blue). The merged fluorescence microscopy image of DEF are shown in panels M-O with high magnification (600×).