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Kitawi R, Ledger S, Kelleher AD, Ahlenstiel CL. Advances in HIV Gene Therapy. Int J Mol Sci 2024; 25:2771. [PMID: 38474018 DOI: 10.3390/ijms25052771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 02/20/2024] [Accepted: 02/20/2024] [Indexed: 03/14/2024] Open
Abstract
Early gene therapy studies held great promise for the cure of heritable diseases, but the occurrence of various genotoxic events led to a pause in clinical trials and a more guarded approach to progress. Recent advances in genetic engineering technologies have reignited interest, leading to the approval of the first gene therapy product targeting genetic mutations in 2017. Gene therapy (GT) can be delivered either in vivo or ex vivo. An ex vivo approach to gene therapy is advantageous, as it allows for the characterization of the gene-modified cells and the selection of desired properties before patient administration. Autologous cells can also be used during this process which eliminates the possibility of immune rejection. This review highlights the various stages of ex vivo gene therapy, current research developments that have increased the efficiency and safety of this process, and a comprehensive summary of Human Immunodeficiency Virus (HIV) gene therapy studies, the majority of which have employed the ex vivo approach.
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Affiliation(s)
- Rose Kitawi
- Kirby Institute, University of New South Wales, Kensington, NSW 2052, Australia
| | - Scott Ledger
- Kirby Institute, University of New South Wales, Kensington, NSW 2052, Australia
| | - Anthony D Kelleher
- Kirby Institute, University of New South Wales, Kensington, NSW 2052, Australia
- St. Vincent's Hospital, Darlinghurst, NSW 2010, Australia
- UNSW RNA Institute, University of New South Wales, Kensington, NSW 2052, Australia
| | - Chantelle L Ahlenstiel
- Kirby Institute, University of New South Wales, Kensington, NSW 2052, Australia
- UNSW RNA Institute, University of New South Wales, Kensington, NSW 2052, Australia
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2
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Duggan NN, Dragic T, Chanda SK, Pache L. Breaking the Silence: Regulation of HIV Transcription and Latency on the Road to a Cure. Viruses 2023; 15:2435. [PMID: 38140676 PMCID: PMC10747579 DOI: 10.3390/v15122435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 12/12/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023] Open
Abstract
Antiretroviral therapy (ART) has brought the HIV/AIDS epidemic under control, but a curative strategy for viral eradication is still needed. The cessation of ART results in rapid viral rebound from latently infected CD4+ T cells, showing that control of viral replication alone does not fully restore immune function, nor does it eradicate viral reservoirs. With a better understanding of factors and mechanisms that promote viral latency, current approaches are primarily focused on the permanent silencing of latently infected cells ("block and lock") or reactivating HIV-1 gene expression in latently infected cells, in combination with immune restoration strategies to eliminate HIV infected cells from the host ("shock and kill"). In this review, we provide a summary of the current, most promising approaches for HIV-1 cure strategies, including an analysis of both latency-promoting agents (LPA) and latency-reversing agents (LRA) that have shown promise in vitro, ex vivo, and in human clinical trials to reduce the HIV-1 reservoir.
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Affiliation(s)
- Natasha N. Duggan
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - Tatjana Dragic
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - Sumit K. Chanda
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037, USA
| | - Lars Pache
- NCI Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
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3
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Czuba-Wojnilowicz E, Klemm V, Cortez-Jugo C, Turville S, Aggarwal A, Caruso F, Kelleher AD, Ahlenstiel CL. Layer-by-Layer Particles Deliver Epigenetic Silencing siRNA to HIV-1 Latent Reservoir Cell Types. Mol Pharm 2023; 20:2039-2052. [PMID: 36848493 DOI: 10.1021/acs.molpharmaceut.2c01030] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
For over two decades, nanomaterials have been employed to facilitate intracellular delivery of small interfering RNA (siRNA), both in vitro and in vivo, to induce post-transcriptional gene silencing (PTGS) via RNA interference. Besides PTGS, siRNAs are also capable of transcriptional gene silencing (TGS) or epigenetic silencing, which targets the gene promoter in the nucleus and prevents transcription via repressive epigenetic modifications. However, silencing efficiency is hampered by poor intracellular and nuclear delivery. Here, polyarginine-terminated multilayered particles are reported as a versatile system for the delivery of TGS-inducing siRNA to potently suppress virus transcription in HIV-infected cells. siRNA is complexed with multilayered particles formed by layer-by-layer assembly of poly(styrenesulfonate) and poly(arginine) and incubated with HIV-infected cell types, including primary cells. Using deconvolution microscopy, uptake of fluorescently labeled siRNA is observed in the nuclei of HIV-1 infected cells. Viral RNA and protein are measured to confirm functional virus silencing from siRNA delivered using particles 16 days post-treatment. This work extends conventional particle-enabled PTGS siRNA delivery to the TGS pathway and paves the way for future studies on particle-delivered siRNA for efficient TGS of various diseases and infections, including HIV.
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Affiliation(s)
- Ewa Czuba-Wojnilowicz
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Vera Klemm
- Kirby Institute, UNSW Medicine, Sydney, New South Wales 2052, Australia
| | - Christina Cortez-Jugo
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Stuart Turville
- Kirby Institute, UNSW Medicine, Sydney, New South Wales 2052, Australia
| | - Anupriya Aggarwal
- Kirby Institute, UNSW Medicine, Sydney, New South Wales 2052, Australia
| | - Frank Caruso
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Anthony D Kelleher
- Kirby Institute, UNSW Medicine, Sydney, New South Wales 2052, Australia.,UNSW RNA Institute, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - Chantelle L Ahlenstiel
- Kirby Institute, UNSW Medicine, Sydney, New South Wales 2052, Australia.,UNSW RNA Institute, UNSW Sydney, Sydney, New South Wales 2052, Australia
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Small Interfering RNAs Targeting a Chromatin-Associated RNA Induce Its Transcriptional Silencing in Human Cells. Mol Cell Biol 2022; 42:e0027122. [PMID: 36445136 PMCID: PMC9753735 DOI: 10.1128/mcb.00271-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Transcriptional gene silencing by small interfering RNAs (siRNAs) has been widely described in various species, including plants and yeast. In mammals, its extent remains somewhat debated. Previous studies showed that siRNAs targeting gene promoters could induce the silencing of the targeted promoter, although the involvement of off-target mechanisms was also suggested. Here, by using nascent RNA capture and RNA polymerase II chromatin immunoprecipitation, we show that siRNAs targeting a chromatin-associated noncoding RNA induced its transcriptional silencing. Deletion of the sequence targeted by one of these siRNAs on the two alleles by genome editing further showed that this silencing was due to base-pairing of the siRNA to the target. Moreover, by using cells with heterozygous deletion of the target sequence, we showed that only the wild-type allele, but not the deleted allele, was silenced by the siRNA, indicating that transcriptional silencing occurred only in cis. Finally, we demonstrated that both Ago1 and Ago2 are involved in this transcriptional silencing. Altogether, our data demonstrate that siRNAs targeting a chromatin-associated RNA at a distance from its promoter induce its transcriptional silencing. Our results thus extend the possible repertoire of endogenous or exogenous interfering RNAs.
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Suzuki K, Levert A, Yeung J, Starr M, Cameron J, Williams R, Rismanto N, Stark T, Druery D, Prasad S, Ferrarini C, Hanafi I, McNally LP, Cunningham P, Liu Z, Ishida T, Huang CS, Oswald V, Evans L, Symonds G, Brew BJ, Zaunders J. HIV-1 viral blips are associated with repeated and increasingly high levels of cell-associated HIV-1 RNA transcriptional activity. AIDS 2021; 35:2095-2103. [PMID: 34148986 PMCID: PMC8505147 DOI: 10.1097/qad.0000000000003001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 06/09/2021] [Accepted: 06/15/2021] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Some HIV+ patients, virally suppressed on ART, show occasional 'blips' of detectable HIV-1 plasma RNA. We used a new highly sensitive assay of cell-associated HIV-1 RNA to measure transcriptional activity in PBMCs and production of infectious virus from the viral reservoir, in patients with and without 'blips'. DESIGN/METHODS RNA and DNA extracted from cells in 6 ml of peripheral blood, from suppressed patients with one to two 'blip' episodes over the past 2 years of ART (n = 55), or no 'blips' (n = 52), were assayed for HIV-1 RNA transcripts and proviral DNA targeting the highly conserved 'R' region of the LTR. Follow-up samples were also collected. Purified CD4+ T cells were cultured with anti-CD3/CD28/CD2 T-cell activator to amplify transcription and measure replication competent virus. RESULTS HIV-1 RNA transcripts ranged from 1.3 to 5415 copies/106 white blood cells. 'Blip' patients had significantly higher levels vs. without blips (median 192 vs. 49; P = 0.0007), which correlated with: higher levels of inducible transcripts after activation in vitro, sustained higher HIV-1 transcription levels in follow-up samples along with increasing HIV-1 DNA in some, and production of replication-competent HIV-1. CONCLUSION Viral 'blips' are significant reflecting higher transcriptional activity from the reservoir and contribute to the reservoir over time. This sensitive assay can be used in monitoring the size and activity of the HIV-1 reservoir and will be useful in HIV-1 cure strategies.
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Affiliation(s)
- Kazuo Suzuki
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Angelique Levert
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Julie Yeung
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Mitchell Starr
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Jane Cameron
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Raffaella Williams
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Nikolas Rismanto
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Tayla Stark
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Dylan Druery
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Salzeena Prasad
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Cristina Ferrarini
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Imelda Hanafi
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Leon Patrick McNally
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Philip Cunningham
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
| | - Zhixin Liu
- Stats Central, University of New South Wales, Sydney, NSW, Australia
| | | | | | - Velma Oswald
- Clinical Immunology and HIV Medicine, Liverpool Hospital
| | - Louise Evans
- Clinical Immunology and HIV Medicine, Liverpool Hospital
- University of New South Wales
| | | | - Bruce James Brew
- Departments of Neurology and Immunology
- Peter Duncan Neurosciences Unit, St Vincent's Centre for Applied Medical Research, and University of Notre Dame
- Department of HIV Medicine, St Vincent's Hospital
- St Vincent's Clinical School, Delacy Building, University of New South Wales, Sydney, NSW, Australia
| | - John Zaunders
- St Vincent's Centre for Applied Medical Research, NSW State Reference laboratory for HIV
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6
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Kelleher AD, Cortez-Jugo C, Cavalieri F, Qu Y, Glanville AR, Caruso F, Symonds G, Ahlenstiel CL. RNAi therapeutics: an antiviral strategy for human infections. Curr Opin Pharmacol 2020; 54:121-129. [PMID: 33171339 DOI: 10.1016/j.coph.2020.09.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 09/20/2020] [Accepted: 09/24/2020] [Indexed: 12/16/2022]
Abstract
Gene silencing induced by RNAi represents a promising antiviral development strategy. This review will summarise the current state of RNAi therapeutics for treating acute and chronic human virus infections. The gene silencing pathways exploited by RNAi therapeutics will be described and include both classic RNAi, inducing cytoplasmic mRNA degradation post-transcription and novel RNAi, mediating epigenetic modifications at the transcription level in the nucleus. Finally, the challenge of delivering gene modifications via RNAi will be discussed, along with the unique characteristics of respiratory versus systemic administration routes to highlight recent advances and future potential of RNAi antiviral treatment strategies.
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Affiliation(s)
| | - Christina Cortez-Jugo
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | | | - Yijiao Qu
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | | | - Frank Caruso
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
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Ahlenstiel CL, Symonds G, Kent SJ, Kelleher AD. Block and Lock HIV Cure Strategies to Control the Latent Reservoir. Front Cell Infect Microbiol 2020; 10:424. [PMID: 32923412 PMCID: PMC7457024 DOI: 10.3389/fcimb.2020.00424] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 07/10/2020] [Indexed: 12/14/2022] Open
Abstract
The HIV latent reservoir represents the major challenge to cure development. Residing in resting CD4+ T cells and myeloid cells at multiple locations in the body, including sanctuary sites such as the brain, the latent reservoir is not eliminated by ART and has the ability to reactivate virus replication to pre-therapy levels when ART is ceased. There are four broad areas of HIV cure research. The only successful cure strategy, thus far, is stem cell transplantation using naturally HIV resistant CCR5Δ32 stem cells. A second potential cure approach uses gene editing technology, such as zinc-finger nucleases and CRISPR/Cas9. Another two cure strategies aim to control the HIV reservoir, with polar opposite concepts; The "shock and kill" approach, which aims to "shock" or reactivate the latent virus and then "kill" infected cells via targeted immune responses. Lastly, the "block and lock" approach, which aims to enhance the latent virus state by "blocking" HIV transcription and "locking" the HIV promoter in a deep latent state via epigenetic modifications. "Shock and kill" approaches are a major focus of cure studies, however we predict that the increased specificity of "block and lock" approaches will be required for the successful development of a sustained HIV clinical remission in the absence of ART. This review focuses on the current research of novel "block and lock" approaches being explored to generate an HIV cure via induction of epigenetic silencing. We will also discuss potential future therapeutic delivery and the challenges associated with progressing "block and lock" cure approaches as these move toward clinical trials.
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Affiliation(s)
| | | | - Stephen J Kent
- Department of Microbiology and Immunology, Peter Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia.,Melbourne Sexual Health Centre and Department of Infectious Diseases, Alfred Hospital and Central Clinical School, Monash University, Melbourne, VIC, Australia.,ARC Centre for Excellence in Convergent Bio-Nano Science and Technology, The University of Melbourne, Parkville, VIC, Australia
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8
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Méndez C, Ledger S, Petoumenos K, Ahlenstiel C, Kelleher AD. RNA-induced epigenetic silencing inhibits HIV-1 reactivation from latency. Retrovirology 2018; 15:67. [PMID: 30286764 PMCID: PMC6172763 DOI: 10.1186/s12977-018-0451-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 10/01/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Current antiretroviral therapy is effective in controlling HIV-1 infection. However, cessation of therapy is associated with rapid return of viremia from the viral reservoir. Eradicating the HIV-1 reservoir has proven difficult with the limited success of latency reactivation strategies and reflects the complexity of HIV-1 latency. Consequently, there is a growing need for alternate strategies. Here we explore a "block and lock" approach for enforcing latency to render the provirus unable to restart transcription despite exposure to reactivation stimuli. Reactivation of transcription from latent HIV-1 proviruses can be epigenetically blocked using promoter-targeted shRNAs to prevent productive infection. We aimed to determine if independent and combined expression of shRNAs, PromA and 143, induce a repressive epigenetic profile that is sufficiently stable to protect latently infected cells from HIV-1 reactivation when treated with a range of latency reversing agents (LRAs). RESULTS J-Lat 9.2 cells, a model of HIV-1 latency, expressing shRNAs PromA, 143, PromA/143 or controls were treated with LRAs to evaluate protection from HIV-1 reactivation as determined by levels of GFP expression. Cells expressing shRNA PromA, 143, or both, showed robust resistance to viral reactivation by: TNF, SAHA, SAHA/TNF, Bryostatin/TNF, DZNep, and Chaetocin. Given the physiological importance of TNF, HIV-1 reactivation was induced by TNF (5 ng/mL) and ChIP assays were performed to detect changes in expression of epigenetic markers within chromatin in both sorted GFP- and GFP+ cell populations, harboring latent or reactivated proviruses, respectively. Ordinary two-way ANOVA analysis used to identify interactions between shRNAs and chromatin marks associated with repressive or active chromatin in the integrated provirus revealed significant changes in the levels of H3K27me3, AGO1 and HDAC1 in the LTR, which correlated with the extent of reduced proviral reactivation. The cell line co-expressing shPromA and sh143 consistently showed the least reactivation and greatest enrichment of chromatin compaction indicators. CONCLUSION The active maintenance of epigenetic silencing by shRNAs acting on the HIV-1 LTR impedes HIV-1 reactivation from latency. Our "block and lock" approach constitutes a novel way of enforcing HIV-1 "super latency" through a closed chromatin architecture that renders the virus resistant to a range of latency reversing agents.
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Affiliation(s)
- Catalina Méndez
- Department of Immunovirology and Pathogenesis, Level 5, Wallace Wurth Building, The Kirby Institute for Infection and Immunity, UNSW Sydney, Kensington, Sydney, NSW, 2052, Australia
| | - Scott Ledger
- Department of Immunovirology and Pathogenesis, Level 5, Wallace Wurth Building, The Kirby Institute for Infection and Immunity, UNSW Sydney, Kensington, Sydney, NSW, 2052, Australia
| | - Kathy Petoumenos
- Department of Immunovirology and Pathogenesis, Level 5, Wallace Wurth Building, The Kirby Institute for Infection and Immunity, UNSW Sydney, Kensington, Sydney, NSW, 2052, Australia
| | - Chantelle Ahlenstiel
- Department of Immunovirology and Pathogenesis, Level 5, Wallace Wurth Building, The Kirby Institute for Infection and Immunity, UNSW Sydney, Kensington, Sydney, NSW, 2052, Australia.
| | - Anthony D Kelleher
- Department of Immunovirology and Pathogenesis, Level 5, Wallace Wurth Building, The Kirby Institute for Infection and Immunity, UNSW Sydney, Kensington, Sydney, NSW, 2052, Australia
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9
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Laham-Karam N, Laitinen P, Turunen TA, Ylä-Herttuala S. Activating the Chromatin by Noncoding RNAs. Antioxid Redox Signal 2018; 29:813-831. [PMID: 28699365 DOI: 10.1089/ars.2017.7248] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE The extent and breadth of transcription have recently been uncovered and this has revealed an extensive array of noncoding RNAs (ncRNAs). The biological role and significance of these ncRNAs have been realized and to date it appears that ncRNAs may have many important regulatory functions. ncRNAs are multifaceted and they induce a complexity of different types of transcriptional and posttranscriptional regulation, including gene activation. Recent Advances: Association of ncRNAs with gene activation is an important finding. Not only enhancer RNA (eRNA) but other types of ncRNAs, including small RNA (sRNA), long-noncoding RNA (lncRNA), microRNA (miRNA), and PIWI-associated RNA (piRNA), have also been implicated in gene activation. Interestingly, they often coincide with histone modifications that favor an open chromatin. In addition, these ncRNAs can recruit key factors important for transcription, including RNA polymerase II. They may directly bind the genomic DNA or act as scaffolds; alternatively, they may loop the chromatin to enhance transcription. CRITICAL ISSUES Although the role of small activating (sa)RNAs has been considerably studied, the roles of miRNAs and piRNAs in gene activation still need to be substantiated and issues of specificity require further studies. FUTURE DIRECTIONS The ncRNA field is coming out of its infancy and we are gaining a global picture of the importance of ncRNAs. However, detailed mechanisms of action of the different ncRNAs are still to be determined. This may reveal novel ways of transcriptional regulation, which will facilitate our ability to utilize these regulatory pathways for research and therapeutic purposes. Antioxid. Redox Signal. 29, 813-831.
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Affiliation(s)
- Nihay Laham-Karam
- 1 A.I. Virtanen Institute, University of Eastern Finland , Kuopio, Finland
| | - Pia Laitinen
- 1 A.I. Virtanen Institute, University of Eastern Finland , Kuopio, Finland
| | - Tiia A Turunen
- 1 A.I. Virtanen Institute, University of Eastern Finland , Kuopio, Finland
| | - Seppo Ylä-Herttuala
- 1 A.I. Virtanen Institute, University of Eastern Finland , Kuopio, Finland .,2 Heart Center, Kuopio University Hospital , Kuopio, Finland .,3 Gene Therapy Unit, Kuopio University Hospital , Kuopio, Finland
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Transcriptional gene silencing limits CXCR4-associated depletion of bone marrow CD34+ cells in HIV-1 infection. AIDS 2018; 32:1737-1747. [PMID: 29762163 DOI: 10.1097/qad.0000000000001882] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVES Hematological abnormalities that include changes in bone marrow, such as in anemia and pancytopenia, are common among HIV-infected patients, particularly in the advanced stage of disease. Such abnormalities may be caused by a reduced bone marrow function for hematopoiesis. The aim of this study was to determine whether transcriptional gene silencing can help to preserve the hosts' hematopoietic potential in addition to peripheral CD4+ T cells against CCR5-tropic HIV infection. DESIGN NOD/SCID/JAK3null (NOJ) mice were transplanted with human cord-derived CD34+ cells with or without transduction with a lentiviral vector expressing a promoter-targeting shRNA called PromA. METHODS At 16 weeks after transplantation, mice engrafted with CD34+ cells were infected with CCR5-tropic HIV-1JRFL. RESULTS At week 2 postinfection, HIV replication was observed in peripheral blood mononuclear cells and splenocytes. In mice transplanted with unmanipulated CD34+ cells, viral replication was accompanied by a loss of peripheral/spleen CD4+CCR5+ T cells. Interestingly, bone marrow CD34+ cells in HIV-infected mice were also depleted, but in a CXCR4-associated manner. Conversely, the lentiviral transfer of PromA in CD34+ cells prior to transplantation rendered the humanized NOJ mice resistant to HIV replication in CD4+ T cells, resulting in better preservation of peripheral/spleen CD4+CCR5+ T cells and bone marrow CD34+ cells at 2 weeks after infection. CONCLUSIONS These results indicate that stable gene transfer of PromA to hematopoietic stem cells not only limited HIV replication but also led to preservation of different subsets of hematopoietic cells, including bone marrow stem/progenitor cells and CD4+ T cells.
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11
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Higaki K, Hirao M, Kawana-Tachikawa A, Iriguchi S, Kumagai A, Ueda N, Bo W, Kamibayashi S, Watanabe A, Nakauchi H, Suzuki K, Kaneko S. Generation of HIV-Resistant Macrophages from IPSCs by Using Transcriptional Gene Silencing and Promoter-Targeted RNA. MOLECULAR THERAPY-NUCLEIC ACIDS 2018; 12:793-804. [PMID: 30141412 PMCID: PMC6111070 DOI: 10.1016/j.omtn.2018.07.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 07/27/2018] [Accepted: 07/27/2018] [Indexed: 12/15/2022]
Abstract
Highly active antiretroviral therapy (HAART) has markedly prolonged the prognosis of HIV-1 patients. However, lifelong dependency on HAART is a continuing challenge, and an effective therapeutic is much desired. Recently, introduction of short hairpin RNA (shRNA) targeting the HIV-1 promoter was found to suppress HIV-1 replication via transcriptional gene silencing (TGS). The technology is expected to be applied with hemato-lymphopoietic cell transplantation of HIV patients to suppress HIV transcription in transplanted hemato-lymphopoietic cells. Combination of the TGS technology with new cell transplantation strategy with induced pluripotent stem cell (iPSC)-derived hemato-lymphopoietic cells might contribute to new gene therapy in the HIV field. In this study, we evaluated iPSC-derived macrophage functions and feasibility of TGS technology in macrophages. Human iPSCs were transduced with shRNAs targeting the HIV-1 promoter region (shPromA) by using a lentiviral vector. The shPromA-transfected iPSCs were successfully differentiated into functional macrophages, and they exhibited strong protection against HIV-1 replication with alteration in the histone structure of the HIV-1 promoter region to induce heterochromatin formation. These results indicated that iPS-derived macrophage is a useful tool to investigate HIV infection and protection, and that the TGS technology targeting the HIV promoter is a potential candidate of new gene therapy.
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Affiliation(s)
- Kei Higaki
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masako Hirao
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Ai Kawana-Tachikawa
- AIDS Research Center, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Shoichi Iriguchi
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Ayako Kumagai
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Norihiro Ueda
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Wang Bo
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Sanae Kamibayashi
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Akira Watanabe
- Watanabe Laboratory, Department of Life Science Frontier, Center for iPS Cell Research and Application (CiRA), Kyoto University, Shogoin, Sakyo-ku, 606-8501 Kyoto, Japan
| | - Hiromitsu Nakauchi
- Division of Stem Cell Therapy, Institute of Medical Science, University of Tokyo, Tokyo, Japan; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kazuo Suzuki
- St Vincent's Centre for Applied Medical Research (AMR), St Vincent's Hospital, Darlinghurst, NSW 2010, Australia.
| | - Shin Kaneko
- Shin Kaneko Laboratory, Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application (CiRA), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
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Shrivastava S, Charlins P, Ackley A, Embree H, Dropulic B, Akkina R, Weinberg MS, Morris KV. Stable Transcriptional Repression and Parasitism of HIV-1. MOLECULAR THERAPY-NUCLEIC ACIDS 2018; 12:12-18. [PMID: 30195752 PMCID: PMC6019856 DOI: 10.1016/j.omtn.2018.04.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 04/27/2018] [Accepted: 04/27/2018] [Indexed: 01/13/2023]
Abstract
Gene-based therapies represent a promising treatment for HIV-1 infection, as they offer the potential for sustained viral inhibition and reduced treatment interventions. One approach developed here involves using conditionally replicating vectors (CR-vectors). CR-vectors utilize HIV-expressed proteins to replicate and disseminate along with HIV into the budding viral particles, thereby co-infecting target cellular reservoirs. We generated and characterized several CR-vectors carrying various therapeutic payloads of non-coding RNAs targeted to HIV-1, both transcriptionally and post-transcriptionally. Both virus and vector expression was followed in cell culture systems and T cells in the presence and absence of mycophenolic acid (MPA) selection. We find here that CR-vectors functionally suppress HIV expression in a long-term stable manner and that transcriptional targeting of and epigenetic silencing of HIV can be passaged to newly infected cells by the action of the CR-vector, ultimately establishing a sustained parasitism of HIV. Our findings suggest that CR-vectors with modulatory non-coding RNAs may be a viable approach to achieving long-term sustained suppression of HIV-1, leading ultimately to a functional cure.
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Affiliation(s)
- Surya Shrivastava
- Hematological Malignancy and Stem Cell Transplantation Institute and Center for Gene Therapy, City of Hope-Beckman Research Institute, 1500 Duarte Road, Duarte, CA 91007, USA
| | - Paige Charlins
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Amanda Ackley
- Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | | | | | - Ramesh Akkina
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Marc S Weinberg
- Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Kevin V Morris
- Hematological Malignancy and Stem Cell Transplantation Institute and Center for Gene Therapy, City of Hope-Beckman Research Institute, 1500 Duarte Road, Duarte, CA 91007, USA; Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA.
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Zhou J, Lazar D, Li H, Xia X, Satheesan S, Charlins P, O'Mealy D, Akkina R, Saayman S, Weinberg MS, Rossi JJ, Morris KV. Receptor-targeted aptamer-siRNA conjugate-directed transcriptional regulation of HIV-1. Am J Cancer Res 2018; 8:1575-1590. [PMID: 29556342 PMCID: PMC5858168 DOI: 10.7150/thno.23085] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 12/09/2017] [Indexed: 12/16/2022] Open
Abstract
Gene-based therapies represent a promising therapeutic paradigm for the treatment of HIV-1, as they have the potential to maintain sustained viral inhibition with reduced treatment interventions. Such an option may represent a long-term treatment alternative to highly active antiretroviral therapy. Methods: We previously described a therapeutic approach, referred to as transcriptional gene silencing (TGS), whereby small noncoding RNAs directly inhibit the transcriptional activity of HIV-1 by targeting sites within the viral promoter, specifically the 5' long terminal repeat (LTR). TGS differs from traditional RNA interference (RNAi) in that it is characterized by concomitant silent-state epigenetic marks on histones and DNA. To deliver TGS-inducing RNAs, we developed functional RNA conjugates based on the previously reported dual function of the gp120 (A-1) aptamer conjugated to 27-mer Dicer-substrate anti-HIV-1 siRNA (dsiRNA), LTR-362. Results: We demonstrate here that high levels of processed guide RNAs localize to the nucleus in infected T lymphoblastoid CEM cell line and primary human CD4+ T-cells. Treatment of the aptamer-siRNA conjugates induced TGS with an ~10-fold suppression of viral p24 levels as measured at day 12 post infection. To explore the silencing efficacy of aptamer-siRNA conjugates in vivo, HIV-1-infected humanized NOD/SCID/IL2 rγnull mice (hu-NSG) were treated with the aptamer-siRNA conjugates. Systemic delivery of the A-1-stick-LTR-362 27-mer siRNA conjugates suppressed HIV-1 infection and protected CD4+ T cell levels in viremia hu-NSG mice. Principle conclusions: Collectively these data suggest that the gp120 aptamer-dsiRNA conjugate design is suitable for systemic delivery of small RNAs that can be used to suppress HIV-1.
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Amsterdam D. Unique natural and adaptive response mechanisms to control and eradicate HIV infection. AIMS ALLERGY AND IMMUNOLOGY 2018. [DOI: 10.3934/allergy.2018.3.113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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15
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Affiliation(s)
- Uri Mbonye
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Jonathan Karn
- Department of Molecular Biology and Microbiology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
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Mechanism of Interferon-Stimulated Gene Induction in HIV-1-Infected Macrophages. J Virol 2017; 91:JVI.00744-17. [PMID: 28768867 DOI: 10.1128/jvi.00744-17] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 06/23/2017] [Indexed: 12/20/2022] Open
Abstract
Viruses manipulate the complex interferon and interferon-stimulated gene (ISG) system in different ways. We have previously shown that HIV inhibits type I and III interferons in its key target cells but directly stimulates a subset of >20 ISGs in macrophages and dendritic cells, many of which are antiviral. Here, we examine the mechanism of induction of ISGs and show this occurs in two phases. The first phase was transient (0 to 24 h postinfection [hpi]), induced mainly by extracellular vesicles and one of its component proteins, HSP90α, contained within the HIV inoculum. The second, dominant, and persistent phase (>48 hpi) was induced via newly transcribed HIV RNA and sensed via RIGI, as shown by the reduction in ISG expression after the knockdown of the RIGI adaptor, MAVS, by small interfering RNA (siRNA) and the inhibition of both the initiation and elongation of HIV transcription by short hairpin RNA (shRNA) transcriptional silencing. We further define the induction pathway, showing sequential HIV RNA stimulation via Tat, RIGI, MAVS, IRF1, and IRF7, also identified by siRNA knockdown. IRF1 also plays a key role in the first phase. We also show that the ISGs IFIT1 to -3 inhibit HIV production, measured as extracellular infectious virus. All induced antiviral ISGs probably lead to restriction of HIV replication in macrophages, contributing to a persistent, noncytopathic infection, while the inhibition of interferon facilitates spread to adjacent cells. Both may influence the size of macrophage HIV reservoirs in vivo Elucidating the mechanisms of ISG induction may help in devising immunotherapeutic strategies to limit the size of these reservoirs.IMPORTANCE HIV, like other viruses, manipulates the antiviral interferon and interferon-stimulated gene (ISG) system to facilitate its initial infection and establishment of viral reservoirs. HIV specifically inhibits all type I and III interferons in its target cells, including macrophages, dendritic cells, and T cells. It also induces a subset of over 20 ISGs of differing compositions in each cell target. This occurs in two temporal phases in macrophages. Extracellular vesicles contained within the inoculum induce the first, transient phase of ISGs. Newly transcribed HIV RNA induce the second, dominant ISG phase, and here, the full induction pathway is defined. Therefore, HIV nucleic acids, which are potent inducers of interferon and ISGs, are initially concealed, and antiviral ISGs are not fully induced until replication is well established. These antiviral ISGs may contribute to persistent infection in macrophages and to the establishment of viral reservoirs in vivo.
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Kwarteng A, Ahuno ST, Kwakye-Nuako G. The therapeutic landscape of HIV-1 via genome editing. AIDS Res Ther 2017; 14:32. [PMID: 28705213 PMCID: PMC5513397 DOI: 10.1186/s12981-017-0157-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 05/30/2017] [Indexed: 12/31/2022] Open
Abstract
Current treatment for HIV-1 largely relies on chemotherapy through the administration of antiretroviral drugs. While the search for anti-HIV-1 vaccine remain elusive, the use of highly active antiretroviral therapies (HAART) have been far-reaching and has changed HIV-1 into a manageable chronic infection. There is compelling evidence, including several side-effects of ARTs, suggesting that eradication of HIV-1 cannot depend solely on antiretrovirals. Gene therapy, an expanding treatment strategy, using RNA interference (RNAi) and programmable nucleases such as meganuclease, zinc finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN), and clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins (CRISPR-Cas9) are transforming the therapeutic landscape of HIV-1. TALENS and ZFNS are structurally similar modular systems, which consist of a FokI endonuclease fused to custom-designed effector proteins but have been largely limited, particularly ZFNs, due to their complexity and cost of protein engineering. However, the newly developed CRISPR-Cas9 system, consists of a single guide RNA (sgRNA), which directs a Cas9 endonuclease to complementary target sites, and serves as a superior alternative to the previous protein-based systems. The techniques have been successfully applied to the development of better HIV-1 models, generation of protective mutations in endogenous/host cells, disruption of HIV-1 genomes and even reactivating latent viruses for better detection and clearance by host immune response. Here, we focus on gene editing-based HIV-1 treatment and research in addition to providing perspectives for refining these techniques.
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Affiliation(s)
- Alexander Kwarteng
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology (KNUST), PMB, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine (KCCR), Kumasi, Ghana
| | - Samuel Terkper Ahuno
- Department of Biochemistry and Biotechnology, Kwame Nkrumah University of Science and Technology (KNUST), PMB, Kumasi, Ghana
| | - Godwin Kwakye-Nuako
- Department of Biomedical Sciences, School of Allied Health Sciences, College of Health and Allied Sciences, University of Cape Coast, Cape Coast, Ghana
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18
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Antiviral treatment strategies based on gene silencing and genome editing. Curr Opin Virol 2017; 24:46-54. [DOI: 10.1016/j.coviro.2017.04.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 04/03/2017] [Accepted: 04/04/2017] [Indexed: 12/18/2022]
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Achieving HIV-1 Control through RNA-Directed Gene Regulation. Genes (Basel) 2016; 7:genes7120119. [PMID: 27941595 PMCID: PMC5192495 DOI: 10.3390/genes7120119] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 11/28/2016] [Accepted: 11/29/2016] [Indexed: 12/13/2022] Open
Abstract
HIV-1 infection has been transformed by combined anti-retroviral therapy (ART), changing a universally fatal infection into a controllable infection. However, major obstacles for an HIV-1 cure exist. The HIV latent reservoir, which exists in resting CD4+ T cells, is not impacted by ART, and can reactivate when ART is interrupted or ceased. Additionally, multi-drug resistance can arise. One alternate approach to conventional HIV-1 drug treatment that is being explored involves gene therapies utilizing RNA-directed gene regulation. Commonly known as RNA interference (RNAi), short interfering RNA (siRNA) induce gene silencing in conserved biological pathways, which require a high degree of sequence specificity. This review will provide an overview of the silencing pathways, the current RNAi technologies being developed for HIV-1 gene therapy, current clinical trials, and the challenges faced in progressing these treatments into clinical trials.
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20
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McAllery SA, Ahlenstiel CL, Suzuki K, Symonds GP, Kelleher AD, Turville SG. The feasibility of incorporating Vpx into lentiviral gene therapy vectors. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2016; 5:16066. [PMID: 27790625 PMCID: PMC5070512 DOI: 10.1038/mtm.2016.66] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 11/09/2022]
Abstract
While current antiretroviral therapy has significantly improved, challenges still remain in life-long targeting of HIV-1 reservoirs. Lentiviral gene therapy has the potential to deliver protective genes into the HIV-1 reservoir. However, inefficient reverse transcription (RT) occurs in HIV-1 reservoirs during lentiviral gene delivery. The viral protein Vpx is capable of increasing lentiviral RT by antagonizing the restriction factor SAMHD1. Incorporating Vpx into lentiviral vectors could substantially increase gene delivery into the HIV-1 reservoir. The feasibility of this Vpx approach was tested in resting cell models utilizing macrophages and dendritic cells. Our results showed Vpx exposure led to increased permissiveness of cells over a period that exceeded 2 weeks. Consequently, significant lower potency of HIV-1 antiretrovirals inhibiting RT and integration was observed. When Vpx was incorporated with anti-HIV-1 genes inhibiting either pre-RT or post-RT stages of the viral life-cycle, transduction levels significantly increased. However, a stronger antiviral effect was only observed with constructs that inhibit pre-RT stages of the viral life cycle. In conclusion this study demonstrates a way to overcome the major delivery obstacle of gene delivery into HIV-1 reservoir cell types. Importantly, incorporating Vpx with pre-RT anti-HIV-1 genes, demonstrated the greatest protection against HIV-1 infection.
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Affiliation(s)
| | | | - Kazuo Suzuki
- St Vincent's Center for Applied Medical Research , Darlinghurst, Australia
| | - Geoff P Symonds
- St Vincent's Center for Applied Medical Research, Darlinghurst, Australia; Calimmune Pty Ltd., Darlinghurst, Australia
| | - Anthony D Kelleher
- The Kirby Institute, University of New South Wales, Sydney, Australia; St Vincent's Center for Applied Medical Research, Darlinghurst, Australia
| | - Stuart G Turville
- The Kirby Institute, University of New South Wales , Sydney, Australia
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21
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Weinberg MS, Morris KV. Transcriptional gene silencing in humans. Nucleic Acids Res 2016; 44:6505-17. [PMID: 27060137 PMCID: PMC5001580 DOI: 10.1093/nar/gkw139] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 02/22/2016] [Accepted: 02/23/2016] [Indexed: 01/21/2023] Open
Abstract
It has been over a decade since the first observation that small non-coding RNAs can functionally modulate epigenetic states in human cells to achieve functional transcriptional gene silencing (TGS). TGS is mechanistically distinct from the RNA interference (RNAi) gene-silencing pathway. TGS can result in long-term stable epigenetic modifications to gene expression that can be passed on to daughter cells during cell division, whereas RNAi does not. Early studies of TGS have been largely overlooked, overshadowed by subsequent discoveries of small RNA-directed post-TGS and RNAi. A reappraisal of early work has been brought about by recent findings in human cells where endogenous long non-coding RNAs function to regulate the epigenome. There are distinct and common overlaps between the proteins involved in small and long non-coding RNA transcriptional regulatory mechanisms, suggesting that the early studies using small non-coding RNAs to modulate transcription were making use of a previously unrecognized endogenous mechanism of RNA-directed gene regulation. Here we review how non-coding RNA plays a role in regulation of transcription and epigenetic gene silencing in human cells by revisiting these earlier studies and the mechanistic insights gained to date. We also provide a list of mammalian genes that have been shown to be transcriptionally regulated by non-coding RNAs. Lastly, we explore how TGS may serve as the basis for development of future therapeutic agents.
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Affiliation(s)
- Marc S Weinberg
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, University of the Witwatersrand, WITS 2050, South Africa HIV Pathogenesis Research Unit, Department of Molecular Medicine and Haematology, School of Pathology, University of the Witwatersrand, WITS 2050, South Africa
| | - Kevin V Morris
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA Center for Gene Therapy, City of Hope - BeckmanResearch Institute; Duarte, CA 91010, USA School of Biotechnology and Biomedical Sciences, University of New South Wales, Kensington, NSW, 2033 Australia
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22
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Glass JJ, Yuen D, Rae J, Johnston APR, Parton RG, Kent SJ, De Rose R. Human immune cell targeting of protein nanoparticles--caveospheres. NANOSCALE 2016; 8:8255-8265. [PMID: 27031090 DOI: 10.1039/c6nr00506c] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Nanotechnology has the power to transform vaccine and drug delivery through protection of payloads from both metabolism and off-target effects, while facilitating specific delivery of cargo to immune cells. However, evaluation of immune cell nanoparticle targeting is conventionally restricted to monocultured cell line models. We generated human caveolin-1 nanoparticles, termed caveospheres, which were efficiently functionalized with monoclonal antibodies. Using this platform, we investigated CD4+ T cell and CD20+ B cell targeting within physiological mixtures of primary human blood immune cells using flow cytometry, imaging flow cytometry and confocal microscopy. Antibody-functionalization enhanced caveosphere binding to targeted immune cells (6.6 to 43.9-fold) within mixed populations and in the presence of protein-containing fluids. Moreover, targeting caveospheres to CCR5 enabled caveosphere internalization by non-phagocytic CD4+ T cells--an important therapeutic target for HIV treatment. This efficient and flexible system of immune cell-targeted caveosphere nanoparticles holds promise for the development of advanced immunotherapeutics and vaccines.
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Affiliation(s)
- Joshua J Glass
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC 3010, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Melbourne, Melbourne, Australia
| | - Daniel Yuen
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Australia
| | - James Rae
- Institute for Molecular Bioscience and Centre for Microscopy and Microanalysis, The University of Queensland, St Lucia, QLD 4072, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St Lucia, Australia
| | - Angus P R Johnston
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Australia
| | - Robert G Parton
- Institute for Molecular Bioscience and Centre for Microscopy and Microanalysis, The University of Queensland, St Lucia, QLD 4072, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St Lucia, Australia
| | - Stephen J Kent
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC 3010, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Melbourne, Melbourne, Australia and Melbourne Sexual Health Centre and Department of Infectious Diseases, Alfred Health, Central Clinical School, Monash University, Melbourne, Australia.
| | - Robert De Rose
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, VIC 3010, Australia and ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Melbourne, Melbourne, Australia
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Novel RNA Duplex Locks HIV-1 in a Latent State via Chromatin-mediated Transcriptional Silencing. MOLECULAR THERAPY. NUCLEIC ACIDS 2015; 4:e261. [PMID: 26506039 PMCID: PMC4881759 DOI: 10.1038/mtna.2015.31] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 08/17/2015] [Indexed: 11/18/2022]
Abstract
Transcriptional gene silencing (TGS) of mammalian genes can be induced by short interfering RNA (siRNA) targeting promoter regions. We previously reported potent TGS of HIV-1 by siRNA (PromA), which targets tandem NF-κB motifs within the viral 5′LTR. In this study, we screened a siRNA panel with the aim of identifying novel 5′LTR targets, to provide multiplexing potential with enhanced viral silencing and application toward developing alternate therapeutic strategies. Systematic examination identified a novel siRNA target, si143, confirmed to induce TGS as the silencing mechanism. TGS was prolonged with virus suppression >12 days, despite a limited ability to induce post- TGS. Epigenetic changes associated with silencing were suggested by partial reversal by histone deacetylase inhibitors and confirmed by chromatin immunoprecipitation analyses, which showed induction of H3K27me3 and H3K9me3, reduction in H3K9Ac, and recruitment of argonaute-1, all characteristic marks of heterochromatin and TGS. Together, these epigenetic changes mimic those associated with HIV-1 latency. Further, robust resistance to reactivation was observed in the J-Lat 9.2 cell latency model, when transduced with shPromA and/or sh143. These data support si/shRNA-mediated TGS approaches to HIV-1 and provide alternate targets to pursue a functional cure, whereby the viral reservoir is locked in latency following antiretroviral therapy cessation.
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Ahlenstiel CL, Suzuki K, Marks K, Symonds GP, Kelleher AD. Controlling HIV-1: Non-Coding RNA Gene Therapy Approaches to a Functional Cure. Front Immunol 2015; 6:474. [PMID: 26441979 PMCID: PMC4584958 DOI: 10.3389/fimmu.2015.00474] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 08/31/2015] [Indexed: 12/27/2022] Open
Abstract
The current treatment strategy for HIV-1 involves prolonged and intensive combined antiretroviral therapy (cART), which successfully suppresses plasma viremia. It has transformed HIV-1 infection into a chronic disease. However, despite the success of cART, a latent form of HIV-1 infection persists as integrated provirus in resting memory CD4(+) T cells. Virus can reactivate from this reservoir upon cessation of treatment, and hence HIV requires lifelong therapy. The reservoir represents a major barrier to eradication. Understanding molecular mechanisms regulating HIV-1 transcription and latency are crucial to develop alternate treatment strategies, which impact upon the reservoir and provide a path toward a "functional cure" in which there is no detectable viremia in the absence of cART. Numerous reports have suggested ncRNAs are involved in regulating viral transcription and latency. This review will discuss the latest developments in ncRNAs, specifically short interfering (si)RNA and short hairpin (sh)RNA, targeting molecular mechanisms of HIV-1 transcription, which may represent potential future therapeutics. It will also briefly address animal models for testing potential therapeutics and current gene therapy clinical trials.
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Affiliation(s)
| | - Kazuo Suzuki
- The Kirby Institute, UNSW Australia, Sydney, NSW, Australia
- Immunovirology Laboratory, St. Vincent’s Centre for Applied Medical Research, Darlinghurst, NSW, Australia
| | - Katherine Marks
- Immunovirology Laboratory, St. Vincent’s Centre for Applied Medical Research, Darlinghurst, NSW, Australia
| | | | - Anthony D. Kelleher
- The Kirby Institute, UNSW Australia, Sydney, NSW, Australia
- Immunovirology Laboratory, St. Vincent’s Centre for Applied Medical Research, Darlinghurst, NSW, Australia
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Méndez C, Ahlenstiel CL, Kelleher AD. Post-transcriptional gene silencing, transcriptional gene silencing and human immunodeficiency virus. World J Virol 2015; 4:219-244. [PMID: 26279984 PMCID: PMC4534814 DOI: 10.5501/wjv.v4.i3.219] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 01/24/2015] [Accepted: 04/29/2015] [Indexed: 02/05/2023] Open
Abstract
While human immunodeficiency virus 1 (HIV-1) infection is controlled through continuous, life-long use of a combination of drugs targeting different steps of the virus cycle, HIV-1 is never completely eradicated from the body. Despite decades of research there is still no effective vaccine to prevent HIV-1 infection. Therefore, the possibility of an RNA interference (RNAi)-based cure has become an increasingly explored approach. Endogenous gene expression is controlled at both, transcriptional and post-transcriptional levels by non-coding RNAs, which act through diverse molecular mechanisms including RNAi. RNAi has the potential to control the turning on/off of specific genes through transcriptional gene silencing (TGS), as well as fine-tuning their expression through post-transcriptional gene silencing (PTGS). In this review we will describe in detail the canonical RNAi pathways for PTGS and TGS, the relationship of TGS with other silencing mechanisms and will discuss a variety of approaches developed to suppress HIV-1 via manipulation of RNAi. We will briefly compare RNAi strategies against other approaches developed to target the virus, highlighting their potential to overcome the major obstacle to finding a cure, which is the specific targeting of the HIV-1 reservoir within latently infected cells.
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26
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Lister NC, Clemson M, Morris KV. RNA-directed epigenetic silencing of Periostin inhibits cell motility. ROYAL SOCIETY OPEN SCIENCE 2015; 2:140545. [PMID: 26543579 PMCID: PMC4632543 DOI: 10.1098/rsos.140545] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 05/14/2015] [Indexed: 06/05/2023]
Abstract
The over-expression of Periostin, a member of the fasciclin family of proteins, has been reported in a number of cancers and, in particular, in metastatic tumours. These include breast, ovarian, lung, colon, head and neck, pancreatic, prostate, neuroblastoma and thyroid cancers. It is thought that Periostin plays a major role in the development of metastases owing to its apparent involvement in restructuring of the extracellular matrix to create a microenvironment favouring invasion and metastases, angiogenesis, independent proliferation, avoidance of apoptosis and the ability for cells to re-enter the cell cycle. As such we reasoned that targeted suppression of Periostin at the promoter and epigenetic level could result in the stable inhibition of cell motility. We find here that promoter-directed small antisense non-coding RNAs can induce transcriptional gene silencing of Periostin that results ultimately in a loss of cellular motility. The observations presented here suggest that cell motility and possibly metastasis can be controlled by transcriptional and epigenetic regulation of Periostin, offering a potentially new and novel manner to control the spread of cancerous cells.
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Affiliation(s)
- Nicholas C. Lister
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - Matthew Clemson
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
| | - Kevin V. Morris
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia
- Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
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27
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Bobbin ML, Burnett JC, Rossi JJ. RNA interference approaches for treatment of HIV-1 infection. Genome Med 2015; 7:50. [PMID: 26019725 PMCID: PMC4445287 DOI: 10.1186/s13073-015-0174-y] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 05/13/2015] [Indexed: 01/05/2023] Open
Abstract
HIV/AIDS is a chronic and debilitating disease that cannot be cured with current antiretroviral drugs. While combinatorial antiretroviral therapy (cART) can potently suppress HIV-1 replication and delay the onset of AIDS, viral mutagenesis often leads to viral escape from multiple drugs. In addition to the pharmacological agents that comprise cART drug cocktails, new biological therapeutics are reaching the clinic. These include gene-based therapies that utilize RNA interference (RNAi) to silence the expression of viral or host mRNA targets that are required for HIV-1 infection and/or replication. RNAi allows sequence-specific design to compensate for viral mutants and natural variants, thereby drastically expanding the number of therapeutic targets beyond the capabilities of cART. Recent advances in clinical and preclinical studies have demonstrated the promise of RNAi therapeutics, reinforcing the concept that RNAi-based agents might offer a safe, effective, and more durable approach for the treatment of HIV/AIDS. Nevertheless, there are challenges that must be overcome in order for RNAi therapeutics to reach their clinical potential. These include the refinement of strategies for delivery and to reduce the risk of mutational escape. In this review, we provide an overview of RNAi-based therapies for HIV-1, examine a variety of combinatorial RNAi strategies, and discuss approaches for ex vivo delivery and in vivo delivery.
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Affiliation(s)
- Maggie L Bobbin
- Irell & Manella School of Biological Sciences, Beckman Research Institute of City of Hope, East Duarte Road, Duarte, CA 91010 USA
| | - John C Burnett
- Irell & Manella School of Biological Sciences, Beckman Research Institute of City of Hope, East Duarte Road, Duarte, CA 91010 USA ; Department of Molecular and Cell Biology, Beckman Research Institute of City of Hope, East Duarte Road, Duarte, CA 9101 USA
| | - John J Rossi
- Irell & Manella School of Biological Sciences, Beckman Research Institute of City of Hope, East Duarte Road, Duarte, CA 91010 USA ; Department of Molecular and Cell Biology, Beckman Research Institute of City of Hope, East Duarte Road, Duarte, CA 9101 USA
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Promoter Targeting RNAs: Unexpected Contributors to the Control of HIV-1 Transcription. MOLECULAR THERAPY-NUCLEIC ACIDS 2015; 4:e222. [PMID: 25625613 PMCID: PMC4345301 DOI: 10.1038/mtna.2014.67] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Accepted: 11/01/2014] [Indexed: 11/22/2022]
Abstract
In spite of prolonged and intensive treatment with combined antiretroviral therapy (cART), which efficiently suppresses plasma viremia, the integrated provirus of HIV-1 persists in resting memory CD4+ T cells as latent infection. Treatment with cART does not substantially reduce the burden of latent infection. Once cART is ceased, HIV-1 replication recrudesces from these reservoirs in the overwhelming majority of patients. There is increasing evidence supporting a role for noncoding RNAs (ncRNA), including microRNAs (miRNAs), antisense (as)RNAs, and short interfering (si)RNA in the regulation of HIV-1 transcription. This appears to be mediated by interaction with the HIV-1 promoter region. Viral miRNAs have the potential to act as positive or negative regulators of HIV transcription. Moreover, inhibition of virally encoded long-asRNA can induce positive transcriptional regulation, while antisense strands of siRNA targeting the NF-κB region suppress viral transcription. An in-depth understanding of the interaction between ncRNAs and the HIV-1 U3 promoter region may lead to new approaches for the control of HIV reservoirs. This review focuses on promoter associated ncRNAs, with particular emphasis on their role in determining whether HIV-1 establishes active or latent infection.
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HIV Latency and the noncoding RNA therapeutic landscape. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 848:169-89. [PMID: 25757621 DOI: 10.1007/978-1-4939-2432-5_9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The Human Immunodeficiency Virus (HIV) belongs to the subfamily of lentiviruses that are characterized by long incubation periods and chronic, persistent infection. The virus integrates into the genome of infected CD4+ cells and, in a subpopulation of cells, adopts a transcriptionally silent state, a process referred to a viral latency. This property makes it exceedingly difficult to therapeutically target the virus and eradicate infection. If left untreated, the inexorable demise of the infected individual's immune system ensues, a causal result of Acquired Immunodeficiency Syndrome (AIDS). Latently infected cells provide a reservoir that maintains viral infection indefinitely. In this chapter we explore the role of noncoding RNAs in HIV infection and in the establishment and maintenance of viral latency. Both short and long noncoding RNAs are endogenous modulators of epigenetic regulation in human cells and play an active role in gene expression. Lastly, we explore therapeutic modalities based on expressed RNAs that are capable of countering infection, transcriptionally regulating the virus, and suppressing or activating the latent state.
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Fan M, Zhang Y, Huang Z, Liu J, Guo X, Zhang H, Luo H. Optimizations of siRNA design for the activation of gene transcription by targeting the TATA-box motif. PLoS One 2014; 9:e108253. [PMID: 25250958 PMCID: PMC4176967 DOI: 10.1371/journal.pone.0108253] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 08/20/2014] [Indexed: 12/24/2022] Open
Abstract
Small interfering RNAs (siRNAs) are widely used to repress gene expression by targeting mRNAs. Some reports reveal that siRNAs can also activate or inhibit gene expression through targeting the gene promoters. Our group has found that microRNAs (miRNAs) could activate gene transcription via interaction with the TATA-box motif in gene promoters. To investigate whether siRNA targeting the same region could upregulate the promoter activity, we test the activating efficiency of siRNAs targeting the TATA-box motif of 16 genes and perform a systematic analysis to identify the common features of the functional siRNAs for effective activation of gene promoters. Further, we try various modifications to improve the activating efficiency of siRNAs and find that it is quite useful to design the promoter-targeting activating siRNA by following several rules such as (a) complementary to the TATA-box-centered region; (b) UA usage at the first two bases of the antisense strand; (c) twenty-three nucleotides (nts) in length; (d) 2'-O-Methyl (2'-OMe) modification at the 3' terminus of the antisense strand; (e) avoiding mismatches at the 3' end of the antisense strand. The optimized activating siRNAs potently enhance the expression of interleukin-2 (IL-2) gene in human and mouse primary CD4+ T cells with a long-time effect. Taken together, our study provides a guideline for rational design the promoter-targeting siRNA to sequence-specifically enhance gene expression.
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Affiliation(s)
- Miaomiao Fan
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yijun Zhang
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Zhuoqiong Huang
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Jun Liu
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xuemin Guo
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Hui Zhang
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- * E-mail: (HZ); (HL)
| | - Haihua Luo
- Institute of Human Virology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
- * E-mail: (HZ); (HL)
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Site-specific host gene modification by zinc finger nucleases: pointing the way to drug free control of HIV-1? Clin Transl Immunology 2014; 3:e19. [PMID: 25505967 PMCID: PMC4232064 DOI: 10.1038/cti.2014.12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 05/12/2014] [Accepted: 05/12/2014] [Indexed: 01/30/2023] Open
Abstract
Anti-retroviral therapy (ART) for human immunodeficiency virus-1 (HIV-1) infection has transformed its clinical course with spectacular reductions in morbidity and mortality, turning this once fatal diagnosis into a manageable chronic infection. However, ART has its limitations. Current ART does not eliminate the virus. Interruption of therapy results in rapid rebound of the virus, and such rebounds are associated with excess morbidity and mortality. This means that therapy once started is for life. This raises the issues of drug resistance due to suboptimal compliance, cumulative toxicities and mounting costs. Efforts to control the virus through novel interventions, particularly through cell or gene therapy have had a resurgence of interest as a single patient was apparently cured by an allogeneic stem cell transplantation from a donor who carried homozygous mutations that disable expression of the HIV-1 co-receptor CCR5. This paper reviews the state of play of gene therapy for HIV infection in the context of a recent paper showing the safety and feasibility of an approach that involves the ex vivo disruption of the ccr5 gene in autologous CD4 T cells using a virally delivered zinc finger nuclease, before their expansion and reinfusion. Although there are still considerable challenges, this approach may point towards a future drug free therapy for HIV-1 infection.
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Harwig A, Das AT, Berkhout B. Retroviral microRNAs. Curr Opin Virol 2014; 7:47-54. [PMID: 24769093 DOI: 10.1016/j.coviro.2014.03.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 03/22/2014] [Accepted: 03/26/2014] [Indexed: 12/18/2022]
Abstract
Eukaryotic cells and several DNA viruses encode miRNAs to regulate the expression of specific target genes. It has been controversial whether RNA viruses can encode such miRNAs as miRNA excision may lead to cleavage of the viral RNA genome. We will focus on the retrovirus family, HIV-1 in particular, and discuss the production of virus-encoded miRNAs and their putative function in the viral replication cycle. An intricate scenario of multi-layer virus-host interactions becomes apparent with small RNAs as the regulatory molecules.
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Affiliation(s)
- Alex Harwig
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Atze T Das
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
| | - Ben Berkhout
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands.
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Kelleher AD. Promoter targeted small RNAs: stabilising viral reservoirs. MICROBIOLOGY AUSTRALIA 2014. [DOI: 10.1071/ma14033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Suzuki K, Hattori S, Marks K, Ahlenstiel C, Maeda Y, Ishida T, Millington M, Boyd M, Symonds G, Cooper DA, Okada S, Kelleher AD. Promoter Targeting shRNA Suppresses HIV-1 Infection In vivo Through Transcriptional Gene Silencing. MOLECULAR THERAPY. NUCLEIC ACIDS 2013; 2:e137. [PMID: 24301868 PMCID: PMC3894581 DOI: 10.1038/mtna.2013.64] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 09/23/2013] [Indexed: 12/25/2022]
Abstract
Despite prolonged and intensive application, combined antiretroviral therapy cannot eradicate human immunodeficiency virus (HIV)-1 because it is harbored as a latent infection, surviving for long periods of time. Alternative approaches are required to overcome the limitations of current therapy. We have been developing a short interfering RNA (siRNA) gene silencing approach. Certain siRNAs targeting promoter regions of genes induce transcriptional gene silencing. We previously reported substantial transcriptional gene silencing of HIV-1 replication by an siRNA targeting the HIV-1 promoter in vitro. In this study, we show that this siRNA, expressed as a short hairpin RNA (shRNA) (shPromA-JRFL) delivered by lentiviral transduction of human peripheral blood mononuclear cells (PBMCs), which are then used to reconstitute NOJ mice, is able to inhibit HIV-1 replication in vivo, whereas a three-base mismatched variant (shPromA-M2) does not. In shPromA-JRFL–treated mice, HIV-1 RNA in serum is significantly reduced, and the ratio of CD4+/CD8+ T cells is significantly elevated. Expression levels of the antisense RNA strand inversely correlates with HIV-1 RNA in serum. The silenced HIV-1 can be reactivated by T-cell activation in ex vivo cultures. HIV-1 suppression is not due to offtarget effects of shPromA-JRFL. These data provide “proof-of principle” that an shRNA targeting the HIV-1 promoter is able to suppress HIV-1 replication in vivo.
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Affiliation(s)
- Kazuo Suzuki
- St. Vincent's Centre for Applied Medical Research, Darlinghurst, New South Wales, Australia
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Singh A, Palanichamy JK, Ramalingam P, Kassab MA, Bhagat M, Andrabi R, Luthra K, Sinha S, Chattopadhyay P. Long-term suppression of HIV-1C virus production in human peripheral blood mononuclear cells by LTR heterochromatization with a short double-stranded RNA. J Antimicrob Chemother 2013; 69:404-15. [PMID: 24022068 DOI: 10.1093/jac/dkt348] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES A region in the conserved 5' long terminal repeat (LTR) promoter of the integrated HIV-1C provirus was identified for effective targeting by a short double-stranded RNA (dsRNA) to cause heterochromatization leading to a long-lasting decrease in viral transcription, replication and subsequent productive infection in human host cells. METHODS Small interfering RNAs (siRNAs) were transfected into siHa cells containing integrated LTR-luciferase reporter constructs and screened for efficiency of inducing transcriptional gene silencing (TGS). TGS was assessed by a dual luciferase assay and real-time PCR. Chromatin modification at the targeted region was also studied. The efficacy of potent siRNA was then checked for effectiveness in TZM-bl cells and human peripheral blood mononuclear cells (PBMCs) infected with HIV-1C virus. Viral Gag-p24 antigen levels were determined by ELISA. RESULTS One HIV-1C LTR-specific siRNA significantly decreased luciferase activity and its mRNA expression with no such effect on HIV-1B LTR. This siRNA-mediated TGS was induced by histone methylation, which leads to heterochromatization of the targeted LTR region. The same siRNA also substantially suppressed viral replication in TZM-bl cells and human PBMCs infected with various HIV-1C clinical isolates for ≥3 weeks after a single transfection, even of a strain that had a mismatch in the target region. CONCLUSIONS We have identified a potent dsRNA that causes long-term suppression of HIV-1C virus production in vitro and ex vivo by heritable epigenetic modification at the targeted C-LTR region. This dsRNA has promising therapeutic potential in HIV-1C infection, the clade responsible for more than half of AIDS cases worldwide.
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Affiliation(s)
- Anand Singh
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, 110029, India
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Chu Y, Kalantari R, Dodd DW, Corey DR. Transcriptional silencing by hairpin RNAs complementary to a gene promoter. Nucleic Acid Ther 2012; 22:147-51. [PMID: 22703280 DOI: 10.1089/nat.2012.0360] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Double-stranded RNAs can target gene promoters and inhibit transcription. To date, most research has focused on synthetic RNA duplexes. Transcriptional silencing by hairpin RNAs would facilitate a better understanding of endogenous RNA-mediated regulation of transcription within cells. Here we examine transcriptional silencing of progesterone receptor (PR) expression by hairpin RNAs. We identify the guide strand as the strand complementary to an antisense transcript at the PR promoter and that hairpin RNAs are active transcriptional silencing agents. The sequence of the hairpin loop affects activity, with the highest activity achieved when the loop has the potential for full complementarity to the antisense transcript target. Introduction of centrally mismatched bases relative to the target transcript does not prevent transcriptional silencing unless the mismatches are present on both the guide and passenger strands. These data demonstrate that hairpin RNAs can cause transcriptional silencing and offer insights into the mechanism of gene modulation by RNAs that target gene promoters.
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Affiliation(s)
- Yongjun Chu
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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37
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Klase Z, Houzet L, Jeang KT. MicroRNAs and HIV-1: complex interactions. J Biol Chem 2012; 287:40884-90. [PMID: 23043098 DOI: 10.1074/jbc.r112.415448] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
RNAi plays important roles in many biological processes, including cellular defense against viral infection. Components of the RNAi machinery are widely conserved in plants and animals. In mammals, microRNAs (miRNAs) represent an abundant class of cell encoded small noncoding RNAs that participate in RNAi-mediated gene silencing. Here, findings that HIV-1 replication in cells can be regulated by miRNAs and that HIV-1 infection of cells can alter cellular miRNA expression are reviewed. Lessons learned from and questions outstanding about the complex interactions between HIV-1 and cellular miRNAs are discussed.
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Affiliation(s)
- Zachary Klase
- Molecular Virology Section, Laboratory of Molecular Microbiology, NIAID, National Institutes of Health, Bethesda, Maryland 20892, USA
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Sampey GC, Guendel I, Das R, Jaworski E, Klase Z, Narayanan A, Kehn-Hall K, Kashanchi F. Transcriptional Gene Silencing (TGS) via the RNAi Machinery in HIV-1 Infections. BIOLOGY 2012; 1:339-69. [PMID: 24832229 PMCID: PMC4009781 DOI: 10.3390/biology1020339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 08/03/2012] [Accepted: 08/13/2012] [Indexed: 12/21/2022]
Abstract
Gene silencing via non-coding RNA, such as siRNA and miRNA, can occur at the transcriptional, post-transcriptional, and translational stages of expression. Transcriptional gene silencing (TGS) involving the RNAi machinery generally occurs through DNA methylation, as well as histone post-translational modifications, and corresponding remodeling of chromatin around the target gene into a heterochromatic state. The mechanism by which mammalian TGS occurs includes the recruitment of RNA-induced initiation of transcriptional gene silencing (RITS) complexes, DNA methyltransferases (DNMTs), and other chromatin remodelers. Additionally, virally infected cells encoding miRNAs have also been shown to manipulate the host cell RNAi machinery to induce TGS at the viral genome, thereby establishing latency. Furthermore, the introduction of exogenous siRNA and shRNA into infected cells that target integrated viral promoters can greatly suppress viral transcription via TGS. Here we examine the latest findings regarding mammalian TGS, specifically focusing on HIV-1 infected cells, and discuss future avenues of exploration in this field.
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Affiliation(s)
- Gavin C Sampey
- National Center for Biodefense and Infectious Disease, School of Systems Biology, George Mason University, 10900 University Blvd, Manassas, VA 20108, USA.
| | - Irene Guendel
- National Center for Biodefense and Infectious Disease, School of Systems Biology, George Mason University, 10900 University Blvd, Manassas, VA 20108, USA.
| | - Ravi Das
- National Center for Biodefense and Infectious Disease, School of Systems Biology, George Mason University, 10900 University Blvd, Manassas, VA 20108, USA.
| | - Elizabeth Jaworski
- National Center for Biodefense and Infectious Disease, School of Systems Biology, George Mason University, 10900 University Blvd, Manassas, VA 20108, USA.
| | - Zachary Klase
- Molecular Virology Section, Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, 9000 Rockville Pike, Bethesda, MD 20810, USA.
| | - Aarthi Narayanan
- National Center for Biodefense and Infectious Disease, School of Systems Biology, George Mason University, 10900 University Blvd, Manassas, VA 20108, USA.
| | - Kylene Kehn-Hall
- National Center for Biodefense and Infectious Disease, School of Systems Biology, George Mason University, 10900 University Blvd, Manassas, VA 20108, USA.
| | - Fatah Kashanchi
- National Center for Biodefense and Infectious Disease, School of Systems Biology, George Mason University, 10900 University Blvd, Manassas, VA 20108, USA.
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Ahlenstiel CL, Lim HGW, Cooper DA, Ishida T, Kelleher AD, Suzuki K. Direct evidence of nuclear Argonaute distribution during transcriptional silencing links the actin cytoskeleton to nuclear RNAi machinery in human cells. Nucleic Acids Res 2011; 40:1579-95. [PMID: 22064859 PMCID: PMC3287199 DOI: 10.1093/nar/gkr891] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Mammalian RNAi machinery facilitating transcriptional gene silencing (TGS) is the RNA-induced transcriptional gene silencing-like (RITS-like) complex, comprising of Argonaute (Ago) and small interfering RNA (siRNA) components. We have previously demonstrated promoter-targeted siRNA induce TGS in human immunodeficiency virus type-1 (HIV-1) and simian immunodeficiency virus (SIV), which profoundly suppresses retrovirus replication via heterochromatin formation and histone methylation. Here, we examine subcellular co-localization of Ago proteins with promoter-targeted siRNAs during TGS of SIV and HIV-1 infection. Analysis of retrovirus-infected cells revealed Ago1 co-localized with siRNA in the nucleus, while Ago2 co-localized with siRNA in the inner nuclear envelope. Mismatched and scrambled siRNAs were observed in the cytoplasm, indicating sequence specificity. This is the first report directly visualizing nuclear compartment distribution of Ago-associated siRNA and further reveals a novel nuclear trafficking mechanism for RITS-like components involving the actin cytoskeleton. These results establish a model for elucidating mammalian TGS and suggest a fundamental mechanism underlying nuclear delivery of RITS-like components.
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