title: Attenuation of HIV-1 replication in primary human cells with a designed zinc finger transcription factor.
abstract: Small molecule inhibitors of human immunodeficiency virus, type 1 (HIV-1) have been extremely successful but are associated with a myriad of undesirable effects and require lifelong daily dosing. In this study we explore an alternative approach, that of inducing intracellular immunity using designed, zinc finger-based transcription factors. Three transcriptional repression proteins were engineered to bind sites in the HIV-1 promoter that were expected to be both accessible in chromatin structure and highly conserved in sequence structure among the various HIV-1 subgroups. Transient transfection assays identified one factor, KRAB-HLTR3, as being able to achieve 100-fold repression of an HIV-1 promoter. Specificity of repression was demonstrated by the lack of repression of other promoters. This factor was further shown to repress the replication of several HIV-1 viral strains 10- to 100-fold in T-cell lines and primary human peripheral blood mononuclear cells. Repression was observed for at least 18 days with no significant cytotoxicity. Stable T-cell lines expressing the factor also do not show obvious signs of cytotoxicity. These characteristics present KRAB-HLTR3 as an attractive candidate for development in an intracellular immunization strategy for anti-HIV-1 therapy.
authors.affiliation: The Skaggs Institute for Chemical Biology and the Departments of Molecular Biology and Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Segal
authors.forename: João
authors.initials: J
authors.lastname: Gonçalves
authors.forename: Scott
authors.initials: S
authors.lastname: Eberhardy
authors.forename: Christina H
authors.initials: CH
authors.lastname: Swan
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Torbett
authors.forename: Xuelin
authors.initials: X
authors.lastname: Li
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Barbas
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D015153:Blotting, Western; D002460:Cell Line; D002478:Cells, Cultured; D002843:Chromatin / Q000737:chemistry; D004247:DNA / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D005434:Flow Cytometry; D017930:Genes, Reporter; D005822:Genetic Vectors; D016325:HIV Long Terminal Repeat; D015497:HIV-1 / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D007700:Kinetics; D016086:Lentivirus / Q000235:genetics; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins / Q000737:chemistry* / Q000378:metabolism; D013601:T-Lymphocytes; D013997:Time Factors; D014157:Transcription Factors / Q000737:chemistry*; D014158:Transcription, Genetic; D014162:Transfection; D014779:Virus Replication; D016335:Zinc Fingers
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; C485217:KRAB-HLTR3 protein; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C422407:ZNF350 protein, human; D004247:DNA