A comparison of gag, pol and rev antisense oligodeoxynucleotides as inhibitors of HIV-1

Sequences from the gag, pol and rev regions of the RF strain of HIV-1 (HIV-1 RF ) were chosen as targets for antisense phosphorothioate oligodeoxynucleotides (S-oligos). These sequences were the p18/p24 junction in gag, the active site of HIV protease in pol; a sequence from the first exon of the rev gene and S -oligodeoxycytidylic acid controls. Compounds were tested against HIV-1 in both acutely and chronically infected cells. The results show that these phosphorothioate analogues tested in acutely infected cells were active in the 0.1–2 μM range, were dependent on chain length but had no sequence specificity. To study the mechanism of action, the time of addition of S -oligos to acutely infected cells was delayed for up to 48 h post-infection. It was found that antiviral activity was lost when compounds were added to the cultures later than 10 h post-infection. With chronically infected cells only the antisense rev sequence showed activity at 30 μM and neither of the gag or pol antisense sequences has a significant effect on HIV replication at 50 μM. These results are consistent with previous in vitro studies which demonstrate that antisense S -oligodeoxynucleotides have several modes of action.