FIG. 6.
Inhibition of p21 reduces HIV-1 replication. (A) p21-specific oligonucleotides (1 and 2, 50 nM), but not a control oligonucleotide (3), inhibit HIV-1 growth in replicate cultures, as determined by p24 levels (data for day 12 are shown and are percentages of the positive HIV control with no oligonucleotide). (B) Macrophages treated with p21 siRNA duplexes (5 nM) 5 days prior to HIV infection (% of positive HIV control with no siRNA treatment) (data shown are from a representative experiment; n = 3). Percentages of HIV-1 infection were determined by comparing the p24 levels in untreated versus oligonucleotide- or siRNA-treated macrophages. The inset is a Western blot for p21 from day 14. (C) Cells treated with p21 and negative control siRNAs (5 days) were analyzed by flow cytometry for CD4 and CCR5 cell surface expression. (D) Nested PCR to detect proviral DNA on days 1 and 2 after HIV-1BaL infection of macrophages treated with p21 siRNA or negative control siRNA. The control represents uninfected cells.