title: A lentiviral vector that activates latent human immunodeficiency virus-1 proviruses by the overexpression of tat and that kills the infected cells.
abstract: Despite the efficient HIV-1 replication blockage achieved with current highly active antiretroviral therapy (HAART) therapies, HIV-1 persists in the body and survives in a latent state that can last for the entire life of the patient. A long-lived reservoir of latently infected CD4(+) memory T cells represents the most important sanctuary for the virus and the greatest obstacle for viral eradication. In this work, we present an initial step toward a gene therapy approach aimed at the activation of latent provirus to induce the death of latently infected T cells. Latent HIV-1 infection is characterized by the failure of viral gene expression as a consequence of uninitiated or aborted transcription. We have constructed an HIV-1-based lentiviral vector (p5p53RTAT3) that expresses the viral trans-activating protein Tat in a drug-regulated manner and p53 in a Rev-dependent manner. We have demonstrated that the Tat-expressed protein from p5p53RTAT3 vector reactivates latent HIV-1 proviruses in J1.1 and ACH-2 cell lines and promotes p53-induced apoptosis in the presence of Rev. Our system was able to trigger the trans-activation of the provirus 5' long terminal repeat (LTR), stimulate the expression of the Rev protein from a tat-defective provirus, and provoke apoptosis selectively in the cells transfected with a tat-defective HIV-1 provirus in contrast to those with no HIV-1 provirus. However, the Rev-dependent p53 killing of latently infected cells was not effective enough for complete elimination of the awakened HIV-1 viruses. In summary, we have developed a vector system that is efficient in activating latent HIV-1 proviruses but that needs further improvement to kill infected cells.
authors: Departamento de Biología Experimental, Universidad de Jaén, Jaén, Spain. d.f.onion@bham.ac.uk
authors: David
authors: D
authors: Macías
authors: Ricardo
authors: R
authors: Oya
authors: Luisa
authors: L
authors: Saniger
authors: Francisco
authors: F
authors: Martín
authors: Francisco
authors: F
authors: Luque
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000235:genetics / Q000628:therapy*; D017209:Apoptosis / Q000502:physiology; D015153:Blotting, Western; D015496:CD4-Positive T-Lymphocytes / Q000821:virology*; D002460:Cell Line; D017931:DNA Primers / Q000235:genetics; D015967:Gene Expression Regulation, Viral / Q000235:genetics / Q000502:physiology*; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics*; D016325:HIV Long Terminal Repeat / Q000235:genetics; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D016086:Lentivirus; D011533:Proviruses / Q000235:genetics / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D014775:Virus Activation / Q000235:genetics / Q000502:physiology*; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000235:genetics / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D016159:Tumor Suppressor Protein p53; D054322:tat Gene Products, Human Immunodeficiency Virus