A Molecular Genetic Intervention for AIDS—Effects of a Transdominant Negative Form of Rev. Hughes Medical Institute Research Laboratories, Ann Arbor, Michigan

Abstract

The HIV-1 Rev protein is encoded by a fully spliced viral mRNA synthesized early in virus infection and required for productive HIV replication (23). Rev facilitates the cytoplasmic appearance of unspliced viral mRNAs and plays a role in the regulation of virus latency (24,25). Mutations in a well-conserved leucine rich domain of Rev give rise to a defective protein that acts as a transdominant inhibitor of HIV replication, which could provide a potential anti-HIV therapy. In this study, we will evaluate the efficacy of intracellular inhibition of HIV infection with a mutant form of Rev, M10. We will introduce the rev M10 gene into peripheral blood CD4⁺ T cells. CD4⁺ cells will be genetically modified in patients using either (a.) a retroviral vector or (b.) a non-viral vector. In each case, a control vector identical to the Rev M10 expression vector but with a frameshift that inactivates gene expression will be used to transduce a parallel population of CD4⁺ cells. These cells will be returned to the patient, and the survival of the cells in each group compared by limiting dilution PCR. In this way, we will determine whether Rev M10 can prolong the survival of CD4⁺ cells in AIDS patients, thus conferring protection against HIV infection. Infection by the human immunodeficiency virus (HIV) leads to progressive loss of the body's immune defenses against infectious agents. Persistent HIV infection therefore leads to an acquired immunodeficiency syndrome (AIDS), for which there are currently no curative treatments. It has recently become clear that the introduction of specific genes into T cells can provide protective effects against HIV growth in the laboratory. One of these protective genes is an altered inactive form of an essential viral gene, called Rev. Expression of this altered form of Rev, called Rev M10, inhibits normal Rev function and blocks productive HIV replication. In this study, we propose to determine whether Rev M10 can improve the survival of T cells in humans. If this approach proves successful, it could provide the basis to develop Rev M10 as a molecular genetic intervention for the treatment of AIDS.