title: Inhibition of HIV-1 by a Lentiviral Vector with a Novel Tat-Inducible Expression System and a Specific Tropism to the Target Cells.
abstract: Today, lentiviral vectors are favorable vectors for RNA interference delivery in anti-HIV therapeutic approaches. Nevertheless, problems such as the specific recognition of target cells and uncontrolled expression of the transgene can restrict their use in vivo. Herein we present a new HIV-inducible promoter to express anti-HIV short hairpin RNA (shRNA) by RNA Pol II in mammalian cells. We likewise showed a novel third-generation lentiviral vector system with more safety and a specific tropism to the target cells. The new promoter, CkRhsp, was constructed from the chicken β-actin core promoter with the R region of HIV-1 long terminal repeat fused upstream of minimal hsp70 promoter. This system was induced by HIV-1 Tat, and activates transcription of two shRNAs against two conserved regions of HIV-1 transcripts produced in two steps of the virus life cycle. We also mimicked HIV-1 cell tropism by using the HIV-1 envelope in structure of third-generation lentiviral vector. The new fusion promoter efficiently expressed shRNA in a Tat-inducible manner. HIV-1 replication was inhibited in transient transfection and stable transduction assays. The new viral vector infected only CD4+cells. CkRhsp promoter may be safer than other inducible promoters for shRNA-mediated gene therapies against HIV. The use of the wild envelope in the vector packaging system may provide the specific targeting T lymphocytes and hematopoietic stem cells for anti-HIV-1 therapeutic approaches in vivo.
authors.affiliation: 1 Department of Molecular Medicine, Faculty of Advanced Medical Technologies, Golestan University of Medical Sciences, Gorgan, Iran.|2 Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Touraj
authors.initials: T
authors.lastname: Farazmandfar
authors.affiliation: 2 Molecular and Cell Biology Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Haghshenas
authors.affiliation: 1 Department of Molecular Medicine, Faculty of Advanced Medical Technologies, Golestan University of Medical Sciences, Gorgan, Iran.|3 Medical Cellular & Molecular Research Center, Taleghani Children Hospital of Golestan University of Medical Sciences , Gorgan, Iran .
authors.forename: Majid
authors.initials: M
authors.lastname: Shahbazi
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism / Q000821:virology; D005822:Genetic Vectors; D015658:HIV Infections / Q000235:genetics* / Q000628:therapy / Q000821:virology; D015497:HIV-1 / Q000235:genetics* / Q000472:pathogenicity; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000627:therapeutic use; D006801:Humans; D016086:Lentivirus; D012319:RNA Polymerase II / Q000235:genetics* / Q000627:therapeutic use; D034741:RNA, Small Interfering; D014161:Transduction, Genetic; D056189:Viral Tropism / Q000235:genetics; D014779:Virus Replication / Q000235:genetics*; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000235:genetics* / Q000627:therapeutic use
chemical_list: D018840:HSP70 Heat-Shock Proteins; D034741:RNA, Small Interfering; D054322:tat Gene Products, Human Immunodeficiency Virus; D012319:RNA Polymerase II