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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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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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Zhang Y, Almazi JG, Ong HX, Johansen MD, Ledger S, Traini D, Hansbro PM, Kelleher AD, Ahlenstiel CL. Nanoparticle Delivery Platforms for RNAi Therapeutics Targeting COVID-19 Disease in the Respiratory Tract. Int J Mol Sci 2022; 23:2408. [PMID: 35269550 PMCID: PMC8909959 DOI: 10.3390/ijms23052408] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 02/14/2022] [Accepted: 02/18/2022] [Indexed: 02/06/2023] Open
Abstract
Since December 2019, a pandemic of COVID-19 disease, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread across the globe. At present, the Food and Drug Administration (FDA) has issued emergency approval for the use of some antiviral drugs. However, these drugs still have limitations in the specific treatment of COVID-19, and as such, new treatment strategies urgently need to be developed. RNA-interference-based gene therapy provides a tractable target for antiviral treatment. Ensuring cell-specific targeted delivery is important to the success of gene therapy. The use of nanoparticles (NPs) as carriers for the delivery of small interfering RNA (siRNAs) to specific tissues or organs of the human body could play a crucial role in the specific therapy of severe respiratory infections, such as COVID-19. In this review, we describe a variety of novel nanocarriers, such as lipid NPs, star polymer NPs, and glycogen NPs, and summarize the pre-clinical/clinical progress of these nanoparticle platforms in siRNA delivery. We also discuss the application of various NP-capsulated siRNA as therapeutics for SARS-CoV-2 infection, the challenges with targeting these therapeutics to local delivery in the lung, and various inhalation devices used for therapeutic administration. We also discuss currently available animal models that are used for preclinical assessment of RNA-interference-based gene therapy. Advances in this field have the potential for antiviral treatments of COVID-19 disease and could be adapted to treat a range of respiratory diseases.
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Affiliation(s)
- Yuan Zhang
- Kirby Institute, UNSW, Sydney, NSW 2052, Australia; (Y.Z.); (S.L.); (A.D.K.)
| | - Juhura G. Almazi
- Respiratory Technology, Woolcock Institute of Medical Research, Sydney, NSW 2037, Australia; (J.G.A.); (H.X.O.); (D.T.)
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Ryde, NSW 2109, Australia
| | - Hui Xin Ong
- Respiratory Technology, Woolcock Institute of Medical Research, Sydney, NSW 2037, Australia; (J.G.A.); (H.X.O.); (D.T.)
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Ryde, NSW 2109, Australia
| | - Matt D. Johansen
- Centre for Inflammation, Faculty of Science, Centenary Institute and University of Technology Sydney, Sydney, NSW 2050, Australia; (M.D.J.); (P.M.H.)
| | - Scott Ledger
- Kirby Institute, UNSW, Sydney, NSW 2052, Australia; (Y.Z.); (S.L.); (A.D.K.)
| | - Daniela Traini
- Respiratory Technology, Woolcock Institute of Medical Research, Sydney, NSW 2037, Australia; (J.G.A.); (H.X.O.); (D.T.)
- Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Ryde, NSW 2109, Australia
| | - Philip M. Hansbro
- Centre for Inflammation, Faculty of Science, Centenary Institute and University of Technology Sydney, Sydney, NSW 2050, Australia; (M.D.J.); (P.M.H.)
| | - Anthony D. Kelleher
- Kirby Institute, UNSW, Sydney, NSW 2052, Australia; (Y.Z.); (S.L.); (A.D.K.)
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4
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Could gene therapy cure HIV? Life Sci 2021; 277:119451. [PMID: 33811896 DOI: 10.1016/j.lfs.2021.119451] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 03/12/2021] [Accepted: 03/27/2021] [Indexed: 02/05/2023]
Abstract
The Human Immunodeficiency Virus (HIV)/Acquired Immune Deficiency Syndrome (AIDS) continues to be a major global public health issue, having claimed almost 33 million lives so far. According to the recent report of the World Health Organization (WHO) in 2019, about 38 million people are living with AIDS. Hence, finding a solution to overcome this life-threatening virus can save millions of lives. Scientists and medical doctors have prescribed HIV patients with specific drugs for many years. Methods such antiretroviral therapy (ART) or latency-reversing agents (LRAs) have been used for a while to treat HIV patients, however they have some side effects and drawbacks causing their application to be not quite successful. Instead, the application of gene therapy which refers to the utilization of the therapeutic delivery of nucleic acids into a patient's cells as a drug to treat disease has shown promising results to control HIV infection. Therefore, in this review, we will summarize recent advances in gene therapy approach against HIV.
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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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Read SA, Obeid S, Ahlenstiel C, Ahlenstiel G. The Role of Zinc in Antiviral Immunity. Adv Nutr 2019; 10:696-710. [PMID: 31305906 PMCID: PMC6628855 DOI: 10.1093/advances/nmz013] [Citation(s) in RCA: 379] [Impact Index Per Article: 75.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 01/17/2019] [Accepted: 01/22/2019] [Indexed: 12/16/2022] Open
Abstract
Zinc is an essential trace element that is crucial for growth, development, and the maintenance of immune function. Its influence reaches all organs and cell types, representing an integral component of approximately 10% of the human proteome, and encompassing hundreds of key enzymes and transcription factors. Zinc deficiency is strikingly common, affecting up to a quarter of the population in developing countries, but also affecting distinct populations in the developed world as a result of lifestyle, age, and disease-mediated factors. Consequently, zinc status is a critical factor that can influence antiviral immunity, particularly as zinc-deficient populations are often most at risk of acquiring viral infections such as HIV or hepatitis C virus. This review summarizes current basic science and clinical evidence examining zinc as a direct antiviral, as well as a stimulant of antiviral immunity. An abundance of evidence has accumulated over the past 50 y to demonstrate the antiviral activity of zinc against a variety of viruses, and via numerous mechanisms. The therapeutic use of zinc for viral infections such as herpes simplex virus and the common cold has stemmed from these findings; however, there remains much to be learned regarding the antiviral mechanisms and clinical benefit of zinc supplementation as a preventative and therapeutic treatment for viral infections.
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Affiliation(s)
- Scott A Read
- Blacktown Medical School, Western Sydney University, Blacktown, New South Wales, Australia
- Storr Liver Centre, The Westmead Institute for Medical Research, The University of Sydney and Westmead Hospital, Westmead, New South Wales, Australia
| | - Stephanie Obeid
- The Kirby Institute, University of New South Wales, Sydney, New South Wales, Australia
| | - Chantelle Ahlenstiel
- The Kirby Institute, University of New South Wales, Sydney, New South Wales, Australia
| | - Golo Ahlenstiel
- Blacktown Medical School, Western Sydney University, Blacktown, New South Wales, Australia
- Storr Liver Centre, The Westmead Institute for Medical Research, The University of Sydney and Westmead Hospital, Westmead, New South Wales, Australia
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Tsukamoto T. Gene Therapy Approaches to Functional Cure and Protection of Hematopoietic Potential in HIV Infection. Pharmaceutics 2019; 11:pharmaceutics11030114. [PMID: 30862061 PMCID: PMC6470728 DOI: 10.3390/pharmaceutics11030114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/05/2019] [Accepted: 03/06/2019] [Indexed: 12/28/2022] Open
Abstract
Although current antiretroviral drug therapy can suppress the replication of human immunodeficiency virus (HIV), a lifelong prescription is necessary to avoid viral rebound. The problem of persistent and ineradicable viral reservoirs in HIV-infected people continues to be a global threat. In addition, some HIV-infected patients do not experience sufficient T-cell immune restoration despite being aviremic during treatment. This is likely due to altered hematopoietic potential. To achieve the global eradication of HIV disease, a cure is needed. To this end, tremendous efforts have been made in the field of anti-HIV gene therapy. This review will discuss the concepts of HIV cure and relative viral attenuation and provide an overview of various gene therapy approaches aimed at a complete or functional HIV cure and protection of hematopoietic functions.
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Affiliation(s)
- Tetsuo Tsukamoto
- Department of Immunology, Kindai University Faculty of Medicine, Osaka 5898511, Japan.
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Wei W, Wang SF, Yu B, Ni M. Inhibition of HBV replication by delivering the dual-gene expression vector pHsa-miR16-siRNA in HepG2.2.15 cells. Curr Med Sci 2017; 37:828-832. [PMID: 29270739 DOI: 10.1007/s11596-017-1810-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 09/13/2017] [Indexed: 10/18/2022]
Abstract
This study aimed to construct the dual-gene expression vector pHsa-miR16-siRNA which can express human miR-16 and HBV X siRNA, and examine its regulatory effect on HBV gene expression in the HepG2.2.15 cell line. The expression vectors siR-1583 and pHsa-miR16-siRNA were designed and constructed. HepG2.2.15 cells were transfected with the empty vector, siR-1583, pmiR-16 and pHsa-miR16-siRNA, respectively. ELISA was performed to measure the expression of HBsAg and HBeAg in the culture supernatant 48 and72 h post transfection. Fluorescence quantitative PCR was used to measure the HBV mRNA degradation efficiency and HBV DNA copy number. The results showed that the expression of HBV genes was significantly inhibited in HepG2.2.15 cells transfected with siR-1583, pmiR-16 and pHsa-miR16-siRNA, respectively, when compared with that in cells transfected with the empty vectors, with the inhibitory effect of pHsa-miR16-siRNA being the most significant. ELISA showed that the inhibitory rates of HBsAg and HBeAg in pHsa-miR16-siRNA transfected cells were correspondingly 87.3% and 85.0% at 48 h, and 88.6% and 86.5% at 72 h post transfection (P<0.01 vs. control group). RT-PCR showed that the level of HBV mRNA decreased by 80.2% (t=-99.22, P<0.01), the genomic HBV DNA by 92.8% (t=-73.06, P<0.01), and the supernatant of HBV DNA copy number by 89.8% (t=-47.13, P<0.01) in pHsa-miR16-siRNA transfected group. It was suggested that the dual-gene expression vector pHsa-miR16-siRNA can inhibit the replication of HBV more efficiently than a single-gene expression vector.
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Affiliation(s)
- Wei Wei
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Su-Fei Wang
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Bing Yu
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Ming Ni
- Department of Infectious Disease, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Boone DR, Leek JM, Falduto MT, Torres KEO, Sell SL, Parsley MA, Cowart JC, Uchida T, Micci MA, DeWitt DS, Prough DS, Hellmich HL. Effects of AAV-mediated knockdown of nNOS and GPx-1 gene expression in rat hippocampus after traumatic brain injury. PLoS One 2017; 12:e0185943. [PMID: 29016640 PMCID: PMC5634593 DOI: 10.1371/journal.pone.0185943] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 09/21/2017] [Indexed: 02/06/2023] Open
Abstract
Virally mediated RNA interference (RNAi) to knock down injury-induced genes could improve functional outcome after traumatic brain injury (TBI); however, little is known about the consequences of gene knockdown on downstream cell signaling pathways and how RNAi influences neurodegeneration and behavior. Here, we assessed the effects of adeno-associated virus (AAV) siRNA vectors that target two genes with opposing roles in TBI pathogenesis: the allegedly detrimental neuronal nitric oxide synthase (nNOS) and the potentially protective glutathione peroxidase 1 (GPx-1). In rat hippocampal progenitor cells, three siRNAs that target different regions of each gene (nNOS, GPx-1) effectively knocked down gene expression. However, in vivo, in our rat model of fluid percussion brain injury, the consequences of AAV-siRNA were variable. One nNOS siRNA vector significantly reduced the number of degenerating hippocampal neurons and showed a tendency to improve working memory. GPx-1 siRNA treatment did not alter TBI-induced neurodegeneration or working memory deficits. Nevertheless, microarray analysis of laser captured, virus-infected neurons showed that knockdown of nNOS or GPx-1 was specific and had broad effects on downstream genes. Since nNOS knockdown only modestly ameliorated TBI-induced working memory deficits, despite widespread genomic changes, manipulating expression levels of single genes may not be sufficient to alter functional outcome after TBI.
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Affiliation(s)
- Deborah R. Boone
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jeanna M. Leek
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | | | | | - Stacy L. Sell
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Margaret A. Parsley
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jeremy C. Cowart
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Tatsuo Uchida
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Maria-Adelaide Micci
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Douglas S. DeWitt
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Donald S. Prough
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Helen L. Hellmich
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail:
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Six Highly Conserved Targets of RNAi Revealed in HIV-1-Infected Patients from Russia Are Also Present in Many HIV-1 Strains Worldwide. MOLECULAR THERAPY. NUCLEIC ACIDS 2017; 8:330-344. [PMID: 28918033 PMCID: PMC5537207 DOI: 10.1016/j.omtn.2017.07.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 07/10/2017] [Accepted: 07/10/2017] [Indexed: 12/26/2022]
Abstract
RNAi has been suggested for use in gene therapy of HIV/AIDS, but the main problem is that HIV-1 is highly variable and could escape attack from the small interfering RNAs (siRNAs) due to even single nucleotide substitutions in the potential targets. To exhaustively check the variability in selected RNA targets of HIV-1, we used ultra-deep sequencing of six regions of HIV-1 from the plasma of two independent cohorts of patients from Russia. Six RNAi targets were found that are invariable in 82%-97% of viruses in both cohorts and are located inside the domains specifying reverse transcriptase (RT), integrase, vpu, gp120, and p17. The analysis of mutation frequencies and their characteristics inside the targets suggests a likely role for APOBEC3G (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G, A3G) in G-to-A mutations and a predominant effect of RT biases in the detected variability of the virus. The lowest frequency of mutations was detected in the central part of all six targets. We also discovered that the identical RNAi targets are present in many HIV-1 strains from many countries and from all continents. The data are important for both the understanding of the patterns of HIV-1 mutability and properties of RT and for the development of gene therapy approaches using RNAi for the treatment of HIV/AIDS.
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