THC Inhibits of KSHV and EBV linear DNA replication. BCBL-1 or P3HR1 cell cultures were grown in standard RPMI/fetal calf serum medium. Cultures were supplemented with either various concentrations of THC dissolved in DMSO (as indicated) or with equivalent volumes of DMSO. After three days, cells were analyzed for latent episomal and lytic linear viral genomes as described [31,32]. Briefly, 106 cells were loaded in wells of a vertical agarose gel then overlaid with a lysis solution containing SDS and pronase, resulting in gentle cell lysis and liberation of cellular and viral DNA. The gel was subjected to electrophoresis. After electrophoresis, Southern blotting was performed and DNA was transferred to nitrocellulose followed by hybridization with radiolabeled overlapping cosmid clone probes of KSHV, representing the entire genome, as described  ( left panel ) or with radiolabeled cloned Bam W fragment of EBV ( right panel ). Latent episomal DNA migrates much more slowly in these gels than linear replicating DNA [31,32]. Arrows on the autoradiograms indicate the position of both species of DNA.