title: Inhibition of human immunodeficiency virus type 1 replication by regulated expression of a polymeric Tat activation response RNA decoy as a strategy for gene therapy in AIDS.
abstract: We are investigating a strategy for somatic gene therapy to treat human immunodeficiency virus type 1 (HIV-1) infection by intracellular expression of an RNA decoy and a ribozyme. The RNA decoy, consisting of polymeric Tat activation response elements (TARs), is designed to compete for Tat binding in an equilibrium with viral TAR RNA, thereby inhibiting viral replication. The expression of polymeric TAR is regulated by the HIV long terminal repeat (LTR) and transcriptional activation is dependent on the presence of HIV Tat. Our initial studies indicated that plasmids expressing up to 50 tandem copies of TAR RNA (50TAR) inhibited tat-mediated gene expression by > 90% in a transient transfection assay. A HIV LTR-driven 50TAR construct was subcloned into a replication-defective retroviral vector to ensure high-efficiency gene transfer into T lymphocytes. In addition, a gag RNA-specific ribozyme gene was introduced into the 50TAR containing retroviral vector to enhance the inhibitory effect of the construct (designated TAR-Rib). A human T-cell line (Molt3) was infected (transduced) with the TAR-Rib recombinant retrovirus and challenged with either HIV-1 or simian immunodeficiency virus (SIV). HIV-1 replication was inhibited by 99% in the TAR-Rib-transduced T cells and was maintained over a 14-month period, suggesting that this antiviral strategy represses the formation of escape mutants. Interestingly, the TAR-Rib also inhibited SIV replication in transduced T cells, which suggests that polymeric TAR is a general inhibitor of primate lentiviruses; therefore, the macaque model could be used for further in vivo testing of this antiviral gene therapy strategy.
authors.affiliation: Laboratory of Tumor Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
authors.forename: J
authors.initials: J
authors.lastname: Lisziewicz
authors.forename: D
authors.initials: D
authors.lastname: Sun
authors.forename: J
authors.initials: J
authors.lastname: Smythe
authors.forename: P
authors.initials: P
authors.lastname: Lusso
authors.forename: F
authors.initials: F
authors.lastname: Lori
authors.forename: A
authors.initials: A
authors.lastname: Louie
authors.forename: P
authors.initials: P
authors.lastname: Markham
authors.forename: J
authors.initials: J
authors.lastname: Rossi
authors.forename: M
authors.initials: M
authors.lastname: Reitz
authors.forename: R C
authors.initials: RC
authors.lastname: Gallo
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000628:therapy*; D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis*; D002460:Cell Line; D002628:Chemoreceptor Cells; D029968:Escherichia coli Proteins; D015696:Gene Products, tat / Q000378:metabolism*; D015750:Genes, gag; D015316:Genetic Therapy; D016325:HIV Long Terminal Repeat; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D017403:In Situ Hybridization; D008565:Membrane Proteins / Q000096:biosynthesis*; D010957:Plasmids; D016337:RNA, Catalytic / Q000378:metabolism*; D012367:RNA, Viral / Q000378:metabolism*; D011956:Receptors, Cell Surface; D015183:Restriction Mapping; D015302:Simian Immunodeficiency Virus / Q000502:physiology*; D013601:T-Lymphocytes; D014162:Transfection; D014779:Virus Replication; D054322:tat Gene Products, Human Immunodeficiency Virus
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D015696:Gene Products, tat; D008565:Membrane Proteins; D016337:RNA, Catalytic; D012367:RNA, Viral; D011956:Receptors, Cell Surface; C057331:Tar protein, E coli; D054322:tat Gene Products, Human Immunodeficiency Virus