FIG. 7.

Amplification of the viral genome. (A) Primary B cells and primary epithelial cells (upper two panels), AdAH epithelial cells (third panels), and AGS epithelial cells (fourth panels) were infected with wild-type recombinant EBV and sorted for GFP expression at 48 h postinfection. The infected cells were examined immediately or after 30 days for viral genome copy number per cell by FISH. The results are displayed as the numbers of viral genomes per cell at 48 h postinfection (left-hand panels) and at 30 days postinfection (right-hand panels). (B) Detection of viral genomes by FISH. Primary B cells and AGS cells were infected at an MOI of 1 with wild-type or BZLF1 KO viruses. The cells were examined at 40 days postinfection for genome amplification. Viral genomes are detected by green fluorescence, and nuclei are identified by DAPI staining. (C) Detection of circular and linear viral genomes by Gardella gel analysis and Southern blotting. PEG-precipitated viral particles were used as a control for linear viral genomes, Raji cells were used as a control for episomal DNA, and LCLs were used as a control for both episomal and linear DNA. The vast majority of viral DNA in AGS cells with amplified viral genomes corresponds to episomal DNA, with a very small proportion being linear.