The Development and Testing of Retroviral Vectors ExpressingTrans-Dominant Mutants of HIV-1 Proteins to Confer Anti-HIV-1 Resistance

Abstract

Trans-dominant mutants of human immunodeficiency virus type 1 (HIV-1) Tat and Rev are attractive candidates for use in gene therapy in the treatment of HIV-1 infections because both are essential for viral replication. Retroviral vectors were constructed to allow either Tat-inducible or Tat- and Rev-inducible expression of trans-dominant mutants of Tat and Rev. These vectors were used to infect a human CD4+ lymphocyte-derived cell line, MT4. To determine the efficacy of various Tat and Rev mutants in inhibiting HIV-1 multiplication, MT4 cells containing mutant-expressing constructs were infected with HIV-1, and the amount of HIV-1 released in the culture medium was measured for up to 30 days. A high level of resistance was observed in cells expressing the double tat/rev mutant in a Tat-inducible manner.

Current develoments and future prospects for HIV gene therapy using interfering RNA-based strategies

“…Upon entry within the nucleus, Tat interacts with the nascent TAR transcripts and increases the processivity of RNA pol II. This results in a 100-1000 fold increase in viral transcription (24,99).…”

Potential nuclease-based strategies for HIV gene therapy

“…INS sequences decrease mRNA stability, whereas the binding of HIV Rev to the RRE overrides this negative effect and increases the half-life of the transcripts produced, making the gene product Rev-inducible (199). MLV-based retroviral vectors allowing Tat-and Rev-inducible gene expression have been constructed (200,201). HIV-based retroviral vectors were also designed to allow Tat-and Rev-inducible production of the therapeutic gene product (202).…”

Gene Therapy for HIV Infections: Intracellular Immunization

“…TNPs lack wild-type activity and interfere with the normal function of their wild type protein counterpart. TPNs of both regulatory (Tat, Rev) and structural (gag, env) genes have been described (27)(28)(29)(30). Perhaps the most investigated TNP is a mutant of Rev protein called RevM10.…”