Agarose gel analysis of DNA from B958 and Raji cells. The study was performed in parallel cultures with or without TPA treatment. TPA treatment (lanes 1 (B958) and 3 (Raji)), untreated cells (lanes 2 (B958) and 4 (Raji)) and untreated lymphocytes used as control (lane 5). B95-8 and Raji cells were harvested at 48 h after EBV lytic cycle induction, and analyzed by 2% agarose gel. EBV lytic cycle induction causes DNA fragmentation in B95-8 as well as Raji cells.