RNA interference targeted to the conserved dimerization initiation site (DIS) of HIV-1 restricts virus escape mutation.

Short hairpin RNAs (shRNA) targeting viral or cellular genes can effectively inhibit human immunodeficiency virus type 1 (HIV-1) replication. This inhibition, however, may induce mutations in the targeted gene, leading to rapid escape from the shRNA-induced inhibition. We generated a lymphoid cell line that stably expressed a 19-bp shRNA targeting a well-conserved dimerization initiation site (DIS) of HIV-1, which strongly inhibited viral replication, thereby delaying virus escape. Furthermore, treatment of HIV-1 infection with DIS- and vif-shRNA combination therapy resulted in superior anti-viral responses compared to vif-shRNA monotherapy. Continuous challenge with HIV-1, however, generated virus mutants that could overcome the RNA interference restriction. Such anti-genes may be promising tools for HIV-1 gene therapy for HIV/acquired immunodeficiency syndrome.