INHIBITION OF HIV-1 REPLICATION BY COMBINED EXPRESSION OF GAG DOMINANT-NEGATIVE MUTANT AND A HUMAN RIBONUCLEASE IN A TIGHTLY CONTROLLED HIV-1 INDUCIBLE VECTOR

An HIV-1-based expression vector has been constructed that produces pr otective genes tightly regulated by HIV-1 Tat and Rev proteins. The ve ctor contains either a single protective gene (HIV-1 gag dominant nega tive mutant (delta-gag)) or a combination of two different protective genes (delta-gag and eosinophil-derived neurotoxin (EDN), a human ribo nuclease) which are expressed from a di-cistronic mRNA. After stable t ransfection of CEM T cells and following challenge with HIV-1, viral p roduction was completely inhibited in cells transduced with the vector producing both delta-gag and EDN and delayed in cells producing delta -gag alone. In addition, cotransfection of HeLa-Tat cells with an infe ctious HIV-1 molecular clone and either protective vector demonstrated that the HIV-1 packaging signals present in the constructs were funct ional and allowed the efficient assembly of the protective RNAs into H IV-1 virions, thus potentially transmitting protection to the HIV-1 ta rget cells.