Stability of HIV-1 regulatory gene mRNAs in primary macrophages and T cells. A: Replication kinetics of HIV-1Ba-L in MDM from a representative donor. Arrows show times at which DRB was added to terminate transcription. B: Relative decay curves for Tat1, Rev1 and Nef1 mRNAs in MDM following addition of DRB as determined by RT-PCR, PAGE and densitometry. Results are expressed as a percentage of levels present immediately after addition of DRB. Mean + SEM from 6 donors. C: Stability of Tat1 and Nef2 mRNA compared to GAPDH mRNA following DRB addition at increasing times after infection in MDM and PBL from the same donor, as determined by real-time PCR. Mean + SEM from 3 donors.