Replication in CEM (A) and H9 (B) cells. Viruses were generated by transfecting 293T cells with proviral DNAs. T cell lines were infected with an M.O.I. of 0.05. The supernatants were collected at day 2, 4, 6, 8, 10, and 12, then subjected to a reverse transcriptase assay to quantitate the amount of virions released at each time point.