Expression of the Tat/Rev antisense gene. At various times following the second reinfusion, PBMC were isolated from the PB of all of the animals. A CD4-enriched cell population was generated by the immunomagnetic depletion of CD8⁺ cells and placed into culture at 1 × 10⁶ cells/mL in AIM-V + 10% FBS + 200 IU/mL rIL-2. On days 0, 3, and 7 postculture, equal aliquots of cells were removed and total cellular RNA was isolated. RT-PCR reactions were performed using 500 ng of RNA and [³²P]-dCTP for detection of the antisense Tat/Rev RNA. Reactions minus the RT were performed as negative controls for this assay. All samples were analyzed on an 8% polyacrylamide gel.