Analysis of viral reactivation after treatment of U1 and ACH-2 cells with NaB. U1 and ACH-2 cells were treated or not (NT) with 10 mM of NaB for 24 h and cocultured with P4 indicating cells. β-galactosidase activity was determined after 24 h coculture (A). RNA from U1 and ACH-2 cells treated or not with NaB were extracted after 24 h and gag viral mRNA expression was measured by real-time RT-PCR (B). Results are representative of three independent experiments.