1
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Huang C, Kaur A, Ji L, Tian H, Webster KA, Li W. Suppression of matrigel-induced choroidal neovascularization by AAV delivery of a novel anti-Scg3 antibody. Gene Ther 2024:10.1038/s41434-024-00491-9. [PMID: 39333408 DOI: 10.1038/s41434-024-00491-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 09/18/2024] [Accepted: 09/20/2024] [Indexed: 09/29/2024]
Abstract
Efforts to develop gene therapy for long-term treatment of neovascular disease are hampered by ongoing concerns that biologics against vascular endothelial growth factor (VEGF) inhibit both physiological and pathological angiogenesis and are therefore at elevated risk of adverse side effects. A potential solution is to develop disease-targeted gene therapy. Secretogranin III (Scg3), a unique disease-restricted angiogenic factor described by our group, contributes significantly to ocular neovascular disease. We have shown that Scg3 blockade with a monoclonal antibody Fab fragment (Fab) stringently inhibits pathological angiogenesis without affecting healthy vessels. Here we tested the therapeutic efficacy of adeno-associated virus (AAV)-anti-Scg3Fab to block choroidal neovascularization (CNV) induced by subretinal injection of Matrigel in a mouse model. Intravitreal AAV-anti-Scg3Fab significantly reduced CNV and suppressed CNV-associated leukocyte infiltration and macrophage activation. The efficacy and anti-inflammatory effects were equivalent to those achieved by positive control AAV-aflibercept against VEGF. Efficacies of AAV-anti-Scg3Fab and AAV-aflibercept were sustained over 4 months post AAV delivery. The findings support development of AAV-anti-Scg3 as an alternative to AAV-anti-VEGF with equivalent efficacy and potentially safer mechanism of action.
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Affiliation(s)
- Chengchi Huang
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Avinash Kaur
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Liyang Ji
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Hong Tian
- Everglades Biopharma, LLC, Houston, TX, 77098, USA
| | - Keith A Webster
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX, 77030, USA
- Everglades Biopharma, LLC, Houston, TX, 77098, USA
- Department of Pharmacology, Vascular Biology Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Wei Li
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, TX, 77030, USA.
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2
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Eisenhut P, Marx N, Borsi G, Papež M, Ruggeri C, Baumann M, Borth N. Corrigendum to "Manipulating gene expression levels in mammalian cell factories: An outline of synthetic molecular toolboxes to achieve multiplexed control" [New Biotechnol 79 (2024) 1-19]. N Biotechnol 2024; 84:30-36. [PMID: 39332183 DOI: 10.1016/j.nbt.2024.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2024]
Affiliation(s)
- Peter Eisenhut
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria
| | - Nicolas Marx
- BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria.
| | - Giulia Borsi
- BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria
| | - Maja Papež
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria; BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria
| | - Caterina Ruggeri
- BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria
| | - Martina Baumann
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria
| | - Nicole Borth
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria; BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria.
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3
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Nomura Y, Kim N, Zhu B, Hamzah M, Zhang H, Yokobayashi Y. Optimization of Exon-Skipping Riboswitches and Their Applications to Control Mammalian Cell Fate. ACS Synth Biol 2024. [PMID: 39318128 DOI: 10.1021/acssynbio.4c00295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/26/2024]
Abstract
Mammalian riboswitches that can regulate transgene expression via RNA-small molecule interaction have promising applications in medicine and biotechnology, as they involve no protein factors that can induce immunogenic reactions and are not dependent on specially engineered promoters. However, the lack of cell-permeable and low-toxicity small molecules and cognate aptamers that can be exploited as riboswitches and the modest switching performance of mammalian riboswitches have limited their applications. In this study, we systematically optimized the design of a riboswitch that regulates exon skipping via an RNA aptamer that binds ASP2905. We examined two design strategies to modulate the stability of the aptamer base stem that blocks the 5' splice site to fine-tune the riboswitch characteristics. Furthermore, an optimized riboswitch was used to generate a mouse embryonic stem cell line that can be chemically induced to differentiate into myogenic cells by activating Myod1 expression and a human embryonic kidney cell line that can be induced to trigger apoptosis by activating BAX expression. The results demonstrate the tight chemical regulation of transgenes in mammalian cells to control their phenotype without exogenous protein factors.
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Affiliation(s)
- Yoko Nomura
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University Onna, Okinawa 9040495, Japan
| | - Narae Kim
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University Onna, Okinawa 9040495, Japan
| | - Bochen Zhu
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University Onna, Okinawa 9040495, Japan
| | - Muhammad Hamzah
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University Onna, Okinawa 9040495, Japan
| | - Haifeng Zhang
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University Onna, Okinawa 9040495, Japan
| | - Yohei Yokobayashi
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University Onna, Okinawa 9040495, Japan
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4
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Steuer J, Sinn M, Eble F, Rütschlin S, Böttcher T, Hartig JS, Peter C. Cooperative binding of bivalent ligands yields new insights into the guanidine-II riboswitch. NAR Genom Bioinform 2024; 6:lqae132. [PMID: 39323654 PMCID: PMC11423145 DOI: 10.1093/nargab/lqae132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 08/23/2024] [Accepted: 09/12/2024] [Indexed: 09/27/2024] Open
Abstract
Riboswitches are involved in regulating the gene expression in bacteria. They are located within the untranslated regions of bacterial messenger RNA and function as switches by adjusting their shape, depending on the presence or absence of specific ligands. To decipher the fundamental aspects of bacterial gene control, it is therefore important to understand the mechanisms that underlie these conformational switches. To this end, a combination of an experimental binding study, molecular simulations and machine learning has been employed to obtain insights into the conformational changes and structural dynamics of the guanidine-II riboswitch. By exploiting the design of a bivalent ligand, we were able to study ligand binding in the aptamer dimer at the molecular level. Spontaneous ligand-binding events, which are usually difficult to simulate, were observed and the contributing factors are described. These findings were further confirmed by in vivo experiments, where the cooperative binding effects of the bivalent ligands resulted in increased binding affinity compared to the native guanidinium ligand. Beyond ligand binding itself, the simulations revealed a novel, ligand-dependent base-stacking interaction outside of the binding pocket that stabilizes the riboswitch.
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Affiliation(s)
- Jakob Steuer
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, 78457 Konstanz, Germany
| | - Malte Sinn
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Franziska Eble
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
| | - Sina Rütschlin
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, 78457 Konstanz, Germany
| | - Thomas Böttcher
- Faculty of Chemistry, Institute for Biological Chemistry & Centre for Microbiology and Environmental Systems Science, Department of Microbiology and Ecosystems Science, University of Vienna, Josef-Holaubek-Platz 2 (UZA II), 1090 Vienna, Austria
| | - Jörg S Hartig
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, 78457 Konstanz, Germany
| | - Christine Peter
- Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, 78457 Konstanz, Germany
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5
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Khaparde A, Mathias GP, Poornachandra B, Thirumalesh MB, Shetty R, Ghosh A. Gene therapy for retinal diseases: From genetics to treatment. Indian J Ophthalmol 2024; 72:1091-1101. [PMID: 39078952 PMCID: PMC11451791 DOI: 10.4103/ijo.ijo_2902_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/31/2024] [Accepted: 04/19/2024] [Indexed: 10/06/2024] Open
Abstract
The gene therapy approach for retinal disorders has been considered largely over the last decade owing to the favorable outcomes of the US Food and Drug Administration-approved commercial gene therapy, Luxturna. Technological advances in recent years, such as next-generation sequencing, research in molecular pathogenesis of retinal disorders, and precise correlations with their clinical phenotypes, have contributed to the progress of gene therapies for various diseases worldwide, and more recently in India as well. Thus, considerable research is being conducted for the right choice of vectors, transgene engineering, and accessible and cost-effective large-scale vector production. Many retinal disease-specific clinical trials are presently being conducted, thereby necessitating the collation of such information as a ready reference for the scientific and clinical community. In this article, we present an overview of existing gene therapy research, which is derived from an extensive search across PubMed, Google Scholar, and clinicaltrials.gov sources. This contributes to prime the understanding of basic aspects of this cutting-edge technology and information regarding current clinical trials across many different conditions. This information will provide a comprehensive evaluation of therapies in existing use/research for personalized treatment approaches in retinal disorders.
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Affiliation(s)
- Ashish Khaparde
- GROW Research Laboratory, Narayana Nethralaya Foundation, Manipal, Karnataka, India
| | - Grace P Mathias
- GROW Research Laboratory, Narayana Nethralaya Foundation, Manipal, Karnataka, India
- Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - B Poornachandra
- Department of Vitreo Retina Services, Narayana Nethralaya, Manipal, Karnataka, India
| | - M B Thirumalesh
- Department of Vitreo Retina Services, Narayana Nethralaya, Manipal, Karnataka, India
| | - Rohit Shetty
- Department of Cornea and Refractive Surgery, Narayana Nethralaya, Bengaluru, Karnataka, India
| | - Arkasubhra Ghosh
- GROW Research Laboratory, Narayana Nethralaya Foundation, Manipal, Karnataka, India
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6
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Lendzioszek M, Bryl A, Poppe E, Zorena K, Mrugacz M. Retinal Vein Occlusion-Background Knowledge and Foreground Knowledge Prospects-A Review. J Clin Med 2024; 13:3950. [PMID: 38999513 PMCID: PMC11242360 DOI: 10.3390/jcm13133950] [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: 05/28/2024] [Revised: 06/28/2024] [Accepted: 07/03/2024] [Indexed: 07/14/2024] Open
Abstract
Thrombosis of retinal veins is one of the most common retinal vascular diseases that may lead to vascular blindness. The latest epidemiological data leave no illusions that the burden on the healthcare system, as impacted by patients with this diagnosis, will increase worldwide. This obliges scientists to search for new therapeutic and diagnostic options. In the 21st century, there has been tremendous progress in retinal imaging techniques, which has facilitated a better understanding of the mechanisms related to the development of retinal vein occlusion (RVO) and its complications, and consequently has enabled the introduction of new treatment methods. Moreover, artificial intelligence (AI) is likely to assist in selecting the best treatment option for patients in the near future. The aim of this comprehensive review is to re-evaluate the old but still relevant data on the RVO and confront them with new studies. The paper will provide a detailed overview of diagnosis, current treatment, prevention, and future therapeutic possibilities regarding RVO, as well as clarifying the mechanism of macular edema in this disease entity.
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Affiliation(s)
- Maja Lendzioszek
- Department of Ophthalmology, Voivodship Hospital, 18-400 Lomza, Poland
| | - Anna Bryl
- Department of Ophthalmology and Eye Rehabilitation, Medical University of Bialystok, 15-089 Bialystok, Poland
| | - Ewa Poppe
- Department of Ophthalmology, Voivodship Hospital, 18-400 Lomza, Poland
| | - Katarzyna Zorena
- Department of Immunobiology and Environment Microbiology, Medical University of Gdansk, Dębinki 7, 80-211 Gdansk, Poland
| | - Malgorzata Mrugacz
- Department of Ophthalmology and Eye Rehabilitation, Medical University of Bialystok, 15-089 Bialystok, Poland
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7
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Luo S, Jiang H, Li Q, Qin Y, Yang S, Li J, Xu L, Gou Y, Zhang Y, Liu F, Ke X, Zheng Q, Sun X. An adeno-associated virus variant enabling efficient ocular-directed gene delivery across species. Nat Commun 2024; 15:3780. [PMID: 38710714 DOI: 10.1038/s41467-024-48221-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 04/24/2024] [Indexed: 05/08/2024] Open
Abstract
Recombinant adeno-associated viruses (rAAVs) have emerged as promising gene therapy vectors due to their proven efficacy and safety in clinical applications. In non-human primates (NHPs), rAAVs are administered via suprachoroidal injection at a higher dose. However, high doses of rAAVs tend to increase additional safety risks. Here, we present a novel AAV capsid (AAVv128), which exhibits significantly enhanced transduction efficiency for photoreceptors and retinal pigment epithelial (RPE) cells, along with a broader distribution across the layers of retinal tissues in different animal models (mice, rabbits, and NHPs) following intraocular injection. Notably, the suprachoroidal delivery of AAVv128-anti-VEGF vector completely suppresses the Grade IV lesions in a laser-induced choroidal neovascularization (CNV) NHP model for neovascular age-related macular degeneration (nAMD). Furthermore, cryo-EM analysis at 2.1 Å resolution reveals that the critical residues of AAVv128 exhibit a more robust advantage in AAV binding, the nuclear uptake and endosome escaping. Collectively, our findings highlight the potential of AAVv128 as a next generation ocular gene therapy vector, particularly using the suprachoroidal delivery route.
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Affiliation(s)
- Shuang Luo
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China
- Sichuan Provincial Key Laboratory of Innovative Biomedicine, Chengdu, 610036, China
| | - Hao Jiang
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
- Sichuan Provincial Key Laboratory of Innovative Biomedicine, Chengdu, 610036, China
| | - Qingwei Li
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
- Sichuan Provincial Key Laboratory of Innovative Biomedicine, Chengdu, 610036, China
| | - Yingfei Qin
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
| | - Shiping Yang
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
| | - Jing Li
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
| | - Lingli Xu
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
| | - Yan Gou
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
| | - Yafei Zhang
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China
| | - Fengjiang Liu
- Innovative Center for Pathogen Research, Guangzhou Laboratory, Guangzhou, 510005, China
| | - Xiao Ke
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China.
- Chengdu Kanghong Pharmaceuticals Group Co Ltd, Chengdu, 610036, China.
| | - Qiang Zheng
- Chengdu Origen Biotechnology Co. Ltd, Chengdu, 610036, China.
- Sichuan Provincial Key Laboratory of Innovative Biomedicine, Chengdu, 610036, China.
| | - Xun Sun
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China.
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8
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Eisenhut P, Marx N, Borsi G, Papež M, Ruggeri C, Baumann M, Borth N. Manipulating gene expression levels in mammalian cell factories: An outline of synthetic molecular toolboxes to achieve multiplexed control. N Biotechnol 2024; 79:1-19. [PMID: 38040288 DOI: 10.1016/j.nbt.2023.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/06/2023] [Accepted: 11/26/2023] [Indexed: 12/03/2023]
Abstract
Mammalian cells have developed dedicated molecular mechanisms to tightly control expression levels of their genes where the specific transcriptomic signature across all genes eventually determines the cell's phenotype. Modulating cellular phenotypes is of major interest to study their role in disease or to reprogram cells for the manufacturing of recombinant products, such as biopharmaceuticals. Cells of mammalian origin, for example Chinese hamster ovary (CHO) and Human embryonic kidney 293 (HEK293) cells, are most commonly employed to produce therapeutic proteins. Early genetic engineering approaches to alter their phenotype have often been attempted by "uncontrolled" overexpression or knock-down/-out of specific genetic factors. Many studies in the past years, however, highlight that rationally regulating and fine-tuning the strength of overexpression or knock-down to an optimum level, can adjust phenotypic traits with much more precision than such "uncontrolled" approaches. To this end, synthetic biology tools have been generated that enable (fine-)tunable and/or inducible control of gene expression. In this review, we discuss various molecular tools used in mammalian cell lines and group them by their mode of action: transcriptional, post-transcriptional, translational and post-translational regulation. We discuss the advantages and disadvantages of using these tools for each cell regulatory layer and with respect to cell line engineering approaches. This review highlights the plethora of synthetic toolboxes that could be employed, alone or in combination, to optimize cellular systems and eventually gain enhanced control over the cellular phenotype to equip mammalian cell factories with the tools required for efficient production of emerging, more difficult-to-express biologics formats.
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Affiliation(s)
- Peter Eisenhut
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria
| | - Nicolas Marx
- BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria.
| | - Giulia Borsi
- BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria
| | - Maja Papež
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria; BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria
| | - Caterina Ruggeri
- BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria
| | - Martina Baumann
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria
| | - Nicole Borth
- Austrian Centre of Industrial Biotechnology (acib GmbH), Muthgasse 11, 1190 Vienna, Austria; BOKU University of Natural Resources and Life Sciences, Institute of Animal Cell Technology and Systems Biology, Muthgasse 18, 1190 Vienna, Austria.
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9
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Düchs MJ, Kratzer RF, Vieyra-Garcia P, Strobel B, Schönberger T, Groß P, Aljayyoussi G, Gupta A, Lang I, Klein H, Morilla SM, Hopf S, Park J, Kreuz S, Klugmann M, Igney FH. Riboswitch-controlled IL-12 gene therapy reduces hepatocellular cancer in mice. Front Immunol 2024; 15:1360063. [PMID: 38558809 PMCID: PMC10979303 DOI: 10.3389/fimmu.2024.1360063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Accepted: 02/14/2024] [Indexed: 04/04/2024] Open
Abstract
Hepatocellular carcinoma (HCC) and solid cancers with liver metastases are indications with high unmet medical need. Interleukin-12 (IL-12) is a proinflammatory cytokine with substantial anti-tumor properties, but its therapeutic potential has not been realized due to severe toxicity. Here, we show that orthotopic liver tumors in mice can be treated by targeting hepatocytes via systemic delivery of adeno-associated virus (AAV) vectors carrying the murine IL-12 gene. Controlled cytokine production was achieved in vivo by using the tetracycline-inducible K19 riboswitch. AAV-mediated expression of IL-12 led to STAT4 phosphorylation, interferon-γ (IFNγ) production, infiltration of T cells and, ultimately, tumor regression. By detailed analyses of efficacy and tolerability in healthy and tumor-bearing animals, we could define a safe and efficacious vector dose. As a potential clinical candidate, we characterized vectors carrying the human IL-12 (huIL-12) gene. In mice, bioactive human IL-12 was expressed in a vector dose-dependent manner and could be induced by tetracycline, suggesting tissue-specific AAV vectors with riboswitch-controlled expression of highly potent proinflammatory cytokines as an attractive approach for vector-based cancer immunotherapy.
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Affiliation(s)
- Matthias J. Düchs
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Ramona F. Kratzer
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Pablo Vieyra-Garcia
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co. KG, Vienna, Austria
| | - Benjamin Strobel
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Tanja Schönberger
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Peter Groß
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Ghaith Aljayyoussi
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Aradhana Gupta
- Nonclinical Drug Safety, Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, United States
| | - Isabel Lang
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Holger Klein
- Global Computational Biology and Digital Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Sandra Martinez Morilla
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co. KG, Ridgefield, CT, United States
| | - Stefan Hopf
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim RCV GmbH & Co. KG, Vienna, Austria
| | - John Park
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Sebastian Kreuz
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Matthias Klugmann
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Frederik H. Igney
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
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10
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Takahashi K, Galloway KE. RNA-based controllers for engineering gene and cell therapies. Curr Opin Biotechnol 2024; 85:103026. [PMID: 38052131 PMCID: PMC11214845 DOI: 10.1016/j.copbio.2023.103026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/12/2023] [Accepted: 11/14/2023] [Indexed: 12/07/2023]
Abstract
Engineered RNA-based genetic controllers provide compact, tunable, post-transcriptional gene regulation. As RNA devices are generally small, these devices are portable to DNA and RNA viral vectors. RNA tools have recently expanded to allow reading and editing of endogenous RNAs for profiling and programming of transcriptional states. With their expanded capabilities and highly compact, modular, and programmable nature, RNA-based controllers will support greater safety, efficacy, and performance in gene and cell-based therapies. In this review, we highlight RNA-based controllers and their potential as user-guided and autonomous systems for control of gene and cell-based therapies.
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Affiliation(s)
- Kei Takahashi
- Department of Chemical Engineering, MIT, 25 Ames St., Cambridge, MA 02139, USA
| | - Kate E Galloway
- Department of Chemical Engineering, MIT, 25 Ames St., Cambridge, MA 02139, USA.
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11
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Kläge D, Müller E, Hartig JS. A comparative survey of the influence of small self-cleaving ribozymes on gene expression in human cell culture. RNA Biol 2024; 21:1-11. [PMID: 38146121 PMCID: PMC10761166 DOI: 10.1080/15476286.2023.2296203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2023] [Indexed: 12/27/2023] Open
Abstract
Self-cleaving ribozymes are versatile tools for synthetic biologists when it comes to controlling gene expression. Up to date, 12 different classes are known, and over the past decades more and more details about their structure, cleavage mechanisms and natural environments have been uncovered. However, when these motifs are applied to mammalian gene expression constructs, the outcome can often be unexpected. A variety of factors, such as surrounding sequences and positioning of the ribozyme influences the activity and hence performance of catalytic RNAs. While some information about the efficiency of individual ribozymes (each tested in specific contexts) is known, general trends obtained from standardized, comparable experiments are lacking, complicating decisions such as which ribozyme to choose and where to insert it into the target mRNA. In many cases, application-specific optimization is required, which can be very laborious. Here, we systematically compared different classes of ribozymes within the 3'-UTR of a given reporter gene. We then examined position-dependent effects of the best-performing ribozymes. Moreover, we tested additional variants of already widely used hammerhead ribozymes originating from various organisms. We were able to identify functional structures suited for aptazyme design and generated highly efficient hammerhead ribozyme variants originating from the human genome. The present dataset will aide decisions about how to apply ribozymes for affecting gene expression as well as for developing ribozyme-based switches for controlling gene expression in human cells.
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Affiliation(s)
- Dennis Kläge
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Konstanz, Germany
| | - Elisabeth Müller
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Konstanz, Germany
| | - Jörg S. Hartig
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Konstanz, Germany
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Rovira E, Moreno B, Razquin N, Blázquez L, Hernández-Alcoceba R, Fortes P, Pastor F. Engineering U1-Based Tetracycline-Inducible Riboswitches to Control Gene Expression in Mammals. ACS NANO 2023; 17:23331-23346. [PMID: 37971502 DOI: 10.1021/acsnano.3c01994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2023]
Abstract
Synthetic riboswitches are promising regulatory devices due to their small size, lack of immunogenicity, and ability to fine-tune gene expression in the absence of exogenous trans-acting factors. Based on a gene inhibitory system developed at our lab, termed U1snRNP interference (U1i), we developed tetracycline (TC)-inducible riboswitches that modulate mRNA polyadenylation through selective U1 snRNP recruitment. First, we engineered different TC-U1i riboswitches, which repress gene expression unless TC is added, leading to inductions of gene expression of 3-to-4-fold. Second, we developed a technique called Systematic Evolution of Riboswitches by Exponential Enrichment (SEREX), to isolate riboswitches with enhanced U1 snRNP binding capacity and activity, achieving inducibilities of up to 8-fold. Interestingly, by multiplexing riboswitches we increased inductions up to 37-fold. Finally, we demonstrated that U1i-based riboswitches are dose-dependent and reversible and can regulate the expression of reporter and endogenous genes in culture cells and mouse models, resulting in attractive systems for gene therapy applications. Our work probes SEREX as a much-needed technology for the in vitro identification of riboswitches capable of regulating gene expression in vivo.
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Affiliation(s)
- Eric Rovira
- Department of Gene Therapy and Regulation of Gene Expression, Center for Applied Medical Research (CIMA), University of Navarra (UNAV), Pamplona 31008, Spain
| | - Beatriz Moreno
- Department of Molecular Therapy, Aptamer Unit, Center for Applied Medical Research (CIMA), University of Navarra (UNAV), Pamplona 31008, Spain
| | - Nerea Razquin
- Department of Gene Therapy and Regulation of Gene Expression, Center for Applied Medical Research (CIMA), University of Navarra (UNAV), Pamplona 31008, Spain
| | - Lorea Blázquez
- Department of Neurosciences, Biodonostia Health Research Institute, 20014 San Sebastián, Spain
- CIBERNED, ISCIII (CIBER, Carlos III Institute, Spanish Ministry of Sciences and Innovation), 28031 Madrid, Spain
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Ruben Hernández-Alcoceba
- Department of Gene Therapy and Regulation of Gene Expression, Center for Applied Medical Research (CIMA), University of Navarra (UNAV), Pamplona 31008, Spain
- Navarra Institute for Health Research (IdiSNA), Pamplona 31008, Spain
- Spanish Network for Advanced Therapies (TERAV ISCIII), Madrid 28029, Spain
| | - Puri Fortes
- Department of Gene Therapy and Regulation of Gene Expression, Center for Applied Medical Research (CIMA), University of Navarra (UNAV), Pamplona 31008, Spain
- Navarra Institute for Health Research (IdiSNA), Pamplona 31008, Spain
- Spanish Network for Advanced Therapies (TERAV ISCIII), Madrid 28029, Spain
- Liver and Digestive Diseases Networking Biomedical Research Centre (CIBERehd), Madrid 28029, Spain
| | - Fernando Pastor
- Department of Molecular Therapy, Aptamer Unit, Center for Applied Medical Research (CIMA), University of Navarra (UNAV), Pamplona 31008, Spain
- Navarra Institute for Health Research (IdiSNA), Pamplona 31008, Spain
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Madrid 28029, Spain
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13
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Huang C, Ji L, Kaur A, Tian H, Waduge P, Webster KA, Li W. Anti-Scg3 Gene Therapy to Treat Choroidal Neovascularization in Mice. Biomedicines 2023; 11:1910. [PMID: 37509549 PMCID: PMC10377229 DOI: 10.3390/biomedicines11071910] [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: 04/22/2023] [Revised: 06/02/2023] [Accepted: 07/04/2023] [Indexed: 07/30/2023] Open
Abstract
Neovascular age-related macular degeneration (nAMD) with choroidal neovascularization (CNV) is a leading cause of blindness in the elderly in developed countries. The disease is currently treated with anti-angiogenic biologics, including aflibercept, against vascular endothelial growth factor (VEGF) but with limited efficacy, treatment resistance and requirement for frequent intravitreal injections. Although anti-VEGF gene therapy may provide sustained therapy that obviates multiple injections, the efficacy and side effects related to VEGF pathway targeting remain, and alternative strategies to block angiogenesis independently of VEGF are needed. We recently reported that secretogranin III (Scg3) induces only pathological angiogenesis through VEGF-independent pathways, and Scg3-neutralizing antibodies selectively inhibit pathological but not physiological angiogenesis in mouse proliferative retinopathy models. Anti-Scg3 antibodies synergize dose-dependently with VEGF inhibitors in a CNV model. Here, we report that an adeno-associated virus-8 (AAV8) vector expressing anti-Scg3 Fab ameliorated CNV with an efficacy similar to that of AAV-aflibercept in a mouse model. This study is the first to test an anti-angiogenic gene therapy protocol that selectively targets pathological angiogenesis via a VEGF-independent mechanism. The findings support further safety/efficacy studies of anti-Scg3 gene therapy as monotherapy or combined with anti-VEGF to treat nAMD.
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Affiliation(s)
- Chengchi Huang
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Liyang Ji
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Avinash Kaur
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hong Tian
- Everglades Biopharma, LLC, Houston, TX 77098, USA
| | - Prabuddha Waduge
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Keith A. Webster
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA
- Everglades Biopharma, LLC, Houston, TX 77098, USA
- Department of Pharmacology, Vascular Biology Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Wei Li
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA
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14
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Parsons NB, Annamalai B, Rohrer B. Regulatable Complement Inhibition of the Alternative Pathway Mitigates Wet Age-Related Macular Degeneration Pathology in a Mouse Model. Transl Vis Sci Technol 2023; 12:17. [PMID: 37462980 PMCID: PMC10362922 DOI: 10.1167/tvst.12.7.17] [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: 03/21/2023] [Accepted: 06/19/2023] [Indexed: 07/21/2023] Open
Abstract
Purpose Risk for developing age-related macular degeneration (AMD) is linked to an overactive complement system. In the mouse model of laser-induced choroidal neovascularization (CNV), elevated levels of complement effector molecules, including complement C3, have been identified, and the alternative pathway (AP) is required for pathology. The main soluble AP regular is complement factor H (fH). We have previously shown that AP inhibition via subretinal AAV-mediated delivery of CR2-fH using a constitutive promoter is efficacious in reducing CNV. Here we ask whether the C3 promoter (pC3) effectively drives CR2-fH bioavailability for gene therapy. Methods Truncated pC3 was used to generate plasmids pC3-mCherry/CR2-fH followed by production of corresponding AAV5 vectors. pC3 activation was determined in transiently transfected ARPE-19 cells stimulated with H2O2 or normal human serum (+/- antioxidant or humanized CR2-fH, respectively). CNV was analyzed in C57BL/6J mice treated subretinally with AAV5-pC3-mCherry/CR2-fH using imaging (optical coherence tomography [OCT] and fundus imaging), functional (electroretinography [ERG]), and molecular (protein expression) readouts. Results Modulation of pC3 in vitro is complement and oxidative stress dependent, as shown by mCherry fluorescence. AAV5-pC3-CR2-fH were identified as safe and effective using OCT and ERG. CR2-fH expression significantly reduced CNV compared to mCherry and was correlated with reduced levels of C3dg/C3d in the retinal pigment epithelium/choroid fraction. Conclusions We conclude that complement-dependent regulation of AP inhibition ameliorates AMD pathology as effectively as using a constitutive promoter. Translational Relevance The goal of anticomplement therapy is to restore homeostatic levels of complement activation, which might be more easily achievable using a self-regulating system.
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Affiliation(s)
- Nathaniel B. Parsons
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | | | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
- Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, USA
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15
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Yuan Y, Kong W, Liu XM, Shi GH. Gene Therapy Activates Retinal Pigment Epithelium Cell Proliferation for Age-related Macular Degeneration in a Mouse Model. Curr Med Sci 2023; 43:384-392. [PMID: 36944806 DOI: 10.1007/s11596-022-2684-3] [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: 02/10/2022] [Accepted: 06/21/2022] [Indexed: 03/23/2023]
Abstract
OBJECTIVE Age-related macular degeneration (AMD) is a degenerative retinal disease. The degeneration or death of retinal pigment epithelium (RPE) cells is implicated in the pathogenesis of AMD. This study aimed to activate the proliferation of RPE cells in vivo by using an adeno-associated virus (AAV) vector encoding β-catenin to treat AMD in a mouse model. METHODS Mice were intravitreally injected with AAV2/8-Y733F-VMD2-β-catenin for 2 or 4 weeks, and β-catenin expression was measured using immunofluorescence staining, real-time quantitative reverse transcription polymerase chain reaction (PCR), and Western blotting. The function of β-catenin was determined using retinal flat mounts and laser-induced damage models. Finally, the safety of AAV2/8-Y733F-VMD2-β-catenin was evaluated by multiple intravitreal injections. RESULTS AAV2/8-Y733F-VMD2-β-catenin induced the expression of β-catenin in RPE cells. It activated the proliferation of RPE cells and increased cyclin D1 expression. It was beneficial to the recovery of laser-induced damage by activating the proliferation of RPE cells. Furthermore, it could induce apoptosis of RPE cells by increasing the expression of Trp53, Bax and caspase3 while decreasing the expression of Bcl-2. CONCLUSION AAV2/8-Y733F-VMD2-β-catenin increased β-catenin expression in RPE cells, activated RPE cell proliferation, and helped mice heal from laser-induced eye injury. Furthermore, it could induce the apoptosis of RPE cells. Therefore, it may be a safe approach for AMD treatment.
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Affiliation(s)
- Yun Yuan
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou, 215000, China.
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science, Suzhou, 215000, China.
| | - Wen Kong
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou, 215000, China
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science, Suzhou, 215000, China
| | - Xiao-Mei Liu
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou, 215000, China
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science, Suzhou, 215000, China
| | - Guo-Hua Shi
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou, 215000, China
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Science, Suzhou, 215000, China
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16
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Romano F, Lamanna F, Gabrielle PH, Teo KYC, Battaglia Parodi M, Iacono P, Fraser-Bell S, Cornish EE, Nassisi M, Viola F, Agarwal A, Samanta A, Chhablani J, Staurenghi G, Invernizzi A. Update on Retinal Vein Occlusion. Asia Pac J Ophthalmol (Phila) 2023; 12:196-210. [PMID: 36912792 DOI: 10.1097/apo.0000000000000598] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 12/11/2022] [Indexed: 03/14/2023] Open
Abstract
Retinal vein occlusion represents the second leading cause of retinal vascular disorders, with a uniform sex distribution worldwide. A thorough evaluation of cardiovascular risk factors is required to correct possible comorbidities. The diagnosis and management of retinal vein occlusion have changed tremendously in the last 30 years, but the assessment of retinal ischemia at baseline and during follow-up examinations remains crucial. New imaging techniques have shed light on the pathophysiology of the disease and laser treatment, once the only therapeutic option, is now only one of the possible approaches with antivascular endothelial growth factors and steroid injections being preferred in most cases. Nowadays long-term outcomes are better than those achievable 20 years ago and yet, many new therapeutic options are under development, including new intravitreal drugs and gene therapy. Despite this, some cases still develop sight-threatening complications deserving a more aggressive (sometimes surgical) approach. The purpose of this comprehensive review is to reappraise some old but still valid concepts and to integrate them with new research and clinical data. The work will provide an overview of the disease's pathophysiology, natural history, and clinical features along with a detailed discussion on the advantages of multimodal imaging and of the different treatment strategies with the aim of providing retina specialists with the most updated knowledge in the field.
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Affiliation(s)
- Francesco Romano
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, Milan, Italy
| | - Francesca Lamanna
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, Milan, Italy
| | | | - Kelvin Y C Teo
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
- Department of Ophthalmology, Save Sight Institute, University of Sydney, Sydney, NSW, Australia
| | - Maurizio Battaglia Parodi
- Vita-Salute San Raffaele University, Milan, Italy
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Pierluigi Iacono
- Vita-Salute San Raffaele University, Milan, Italy
- Department of Ophthalmology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Samantha Fraser-Bell
- Department of Ophthalmology, Save Sight Institute, University of Sydney, Sydney, NSW, Australia
| | - Elisa E Cornish
- Department of Ophthalmology, Save Sight Institute, University of Sydney, Sydney, NSW, Australia
| | - Marco Nassisi
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- Ophthalmological Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Francesco Viola
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
- Ophthalmological Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Aniruddha Agarwal
- Eye Institute, Cleveland Clinic, Abu Dhabi, United Arab Emirates
- Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, US
- Department of Ophthalmology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Anindya Samanta
- Department of Ophthalmology and Visual Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, US
| | - Jay Chhablani
- University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Giovanni Staurenghi
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, Milan, Italy
| | - Alessandro Invernizzi
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, Milan, Italy
- Department of Ophthalmology, Save Sight Institute, University of Sydney, Sydney, NSW, Australia
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17
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Shitik EM, Shalik IK, Yudkin DV. AAV- based vector improvements unrelated to capsid protein modification. Front Med (Lausanne) 2023; 10:1106085. [PMID: 36817775 PMCID: PMC9935841 DOI: 10.3389/fmed.2023.1106085] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Recombinant adeno-associated virus (rAAV) is the leading platform for delivering genetic constructs in vivo. To date, three AAV-based gene therapeutic agents have been approved by the FDA and are used in clinical practice. Despite the distinct advantages of gene therapy development, it is clear that AAV vectors need to be improved. Enhancements in viral vectors are mainly associated with capsid protein modifications. However, there are other structures that significantly affect the AAV life cycle and transduction. The Rep proteins, in combination with inverted terminal repeats (ITRs), determine viral genome replication, encapsidation, etc. Moreover, transgene cassette expression in recombinant variants is directly related to AAV production and transduction efficiency. This review discusses the ways to improve AAV vectors by modifying ITRs, a transgene cassette, and the Rep proteins.
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18
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Chern KJ, Nettesheim ER, Reid CA, Li NW, Marcoe GJ, Lipinski DM. Prostaglandin-based rAAV-mediated glaucoma gene therapy in Brown Norway rats. Commun Biol 2022; 5:1169. [PMID: 36329259 PMCID: PMC9633612 DOI: 10.1038/s42003-022-04134-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022] Open
Abstract
Prostaglandin analogs are first-line treatments for open angle glaucoma and while effective at lowering intraocular pressure, they are undermined by patient non-compliance, causing atrophy of the optic nerve and severe visual impairment. Herein, we evaluate the safety and efficacy of a recombinant adeno-associated viral vector-mediated gene therapy aimed at permanently lowering intraocular pressure through de novo biosynthesis of prostaglandin F2α within the anterior chamber. This study demonstrated a dose dependent reduction in intraocular pressure in normotensive Brown Norway rats maintained over 12-months. Crucially, therapy could be temporarily halted through off-type riboswitch activation, reverting intraocular pressure to normal. Longitudinal multimodal imaging, electrophysiology, and post-mortem histology revealed the therapy was well tolerated at low and medium doses, with no major adverse effects to anterior chamber health, offering a promising alternative to current treatment strategies leading to clinically relevant reductions in intraocular pressure without the need for adherence to a daily treatment regimen.
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Affiliation(s)
- Kristina J Chern
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Emily R Nettesheim
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Christopher A Reid
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Nathan W Li
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Gavin J Marcoe
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Daniel M Lipinski
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA.
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA.
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19
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Stradiotto E, Allegrini D, Fossati G, Raimondi R, Sorrentino T, Tripepi D, Barone G, Inforzato A, Romano MR. Genetic Aspects of Age-Related Macular Degeneration and Their Therapeutic Potential. Int J Mol Sci 2022; 23:13280. [PMID: 36362067 PMCID: PMC9653831 DOI: 10.3390/ijms232113280] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/05/2022] [Accepted: 10/28/2022] [Indexed: 08/27/2023] Open
Abstract
Age-related macular degeneration (AMD) is a complex and multifactorial disease, resulting from the interaction of environmental and genetic factors. The continuous discovery of associations between genetic polymorphisms and AMD gives reason for the pivotal role attributed to the genetic component to its development. In that light, genetic tests and polygenic scores have been created to predict the risk of development and response to therapy. Still, none of them have yet been validated. Furthermore, there is no evidence from a clinical trial that the determination of the individual genetic structure can improve treatment outcomes. In this comprehensive review, we summarize the polymorphisms of the main pathogenetic ways involved in AMD development to identify which of them constitutes a potential therapeutic target. As complement overactivation plays a major role, the modulation of targeted complement proteins seems to be a promising therapeutic approach. Herein, we summarize the complement-modulating molecules now undergoing clinical trials, enlightening those in an advanced phase of trial. Gene therapy is a potential innovative one-time treatment, and its relevance is quickly evolving in the field of retinal diseases. We describe the state of the art of gene therapies now undergoing clinical trials both in the field of complement-suppressors and that of anti-VEGF.
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Affiliation(s)
- Elisa Stradiotto
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
| | - Davide Allegrini
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
| | - Giovanni Fossati
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
| | - Raffaele Raimondi
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
| | - Tania Sorrentino
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
| | - Domenico Tripepi
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
| | - Gianmaria Barone
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
| | - Antonio Inforzato
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- IRCCS Humanitas Research Hospital, Via Manzoni 56, 20089 Rozzano-Milan, Italy
| | - Mario R. Romano
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy
- Department of Ophthalmology, Eye Unit Humanitas Gavazzeni-Castelli, Via Mazzini 11, 24128 Bergamo, Italy
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20
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Dykstra PB, Rando TA, Smolke CD. Modulating myoblast differentiation with RNA-based controllers. PLoS One 2022; 17:e0275298. [PMID: 36166456 PMCID: PMC9514614 DOI: 10.1371/journal.pone.0275298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 09/13/2022] [Indexed: 02/03/2023] Open
Abstract
Tunable genetic controllers play a critical role in the engineering of biological systems that respond to environmental and cellular signals. RNA devices, a class of engineered RNA-based controllers, enable tunable gene expression control of target genes in response to molecular effectors. RNA devices have been demonstrated in a number of systems showing proof-of-concept of applying ligand-responsive control over therapeutic activities, including regulation of cell fate decisions such as T cell proliferation and apoptosis. Here, we describe the application of a theophylline-responsive RNA device in a muscle progenitor cell system to control myogenic differentiation. Ribozyme-based RNA switches responsive to theophylline control fluorescent reporter expression in C2C12 myoblasts in a ligand dependent manner. HRAS and JAK1, both anti-differentiation proteins, were incorporated into RNA devices. Finally, we demonstrate that the regulation of HRAS expression via theophylline-responsive RNA devices results in the modulation of myoblast differentiation in a theophylline-dependent manner. Our work highlights the potential for RNA devices to exert drug-responsive, tunable control over cell fate decisions with applications in stem cell therapy and basic stem cell biology research.
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Affiliation(s)
- Peter B. Dykstra
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Thomas A. Rando
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, United States of America
- Paul F. Glenn Center for the Biology of Aging, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Christina D. Smolke
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
- Chan Zuckerberg Biohub, San Francisco, CA, United States of America
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21
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Toutounchian S, Ahmadbeigi N, Mansouri V. Retinal and Choroidal Neovascularization Antivascular Endothelial Growth Factor Treatments: The Role of Gene Therapy. J Ocul Pharmacol Ther 2022; 38:529-548. [PMID: 36125411 DOI: 10.1089/jop.2022.0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Neovascularization in ocular vessels causes a major disease burden. The most common causes of choroidal neovascularization (CNV) are age-related macular degeneration and diabetic retinopathy, which are the leading causes of irreversible vision loss in the adult population. Vascular endothelial growth factor (VEGF) is critical for the formation of new vessels and is the main regulator in ocular angiogenesis and vascular permeability through its receptors. Laser therapy and antiangiogenic factors have been used for CNV treatment. Bevacizumab, ranibizumab, and aflibercept are commonly used anti-VEGF agents; however, high costs and the need for frequent intraocular injections are major drawbacks of anti-VEGF drugs. Gene therapy, given the potency of one-time treatment and no need for frequent injections offers the real possibility of such a lasting treatment, with fewer adverse effects and higher patient quality of life. Herein, we reviewed the role of gene therapy in the CNV treatment. In addition, we discuss the advantages and challenges of current treatments compared with gene therapy.
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Affiliation(s)
- Samaneh Toutounchian
- Gene Therapy Research Center, Digestive Diseases Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Naser Ahmadbeigi
- Gene Therapy Research Center, Digestive Diseases Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Vahid Mansouri
- Gene Therapy Research Center, Digestive Diseases Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
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22
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Osterman MD, Song YE, Nittala M, Sadda SR, Scott WK, Stambolian D, Pericak-Vance MA, Haines JL. Genomewide Association Study of Retinal Traits in the Amish Reveals Loci Influencing Drusen Development and Link to Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2022; 63:17. [PMID: 35857289 PMCID: PMC9315071 DOI: 10.1167/iovs.63.8.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Purpose The purpose of this study was to identify genetic risk loci for retinal traits, including drusen, in an Amish study population and compare these risk loci to known risk loci of age-related macular degeneration (AMD). Methods Participants were recruited from Amish communities in Ohio, Indiana, and Pennsylvania. Each participant underwent a basic health history, ophthalmologic examination, and genotyping. A genomewide association analysis (GWAS) was conducted for the presence and quantity of each of three retinal traits: geographic atrophy, drusen area, and drusen volume. The findings were compared to results from a prior large GWAS of predominantly European-ancestry individuals. Further, a genetic risk score for AMD was used to predict the presence and quantity of the retinal traits. Results After quality control, 1074 participants were included in analyses. Six single nucleotide polymorphisms (SNPs) met criteria for genomewide significance and 48 were suggestively associated across three retinal traits. The significant SNPs were not highly correlated with known risk SNPs for AMD. A genetic risk score for AMD provided significant predictive value of the retinal traits. Conclusions We identified potential novel genetic risk loci for AMD in a midwestern Amish study population. Additionally, we determined that there is a clear link between the genetic risk of AMD and drusen. Further study, including longitudinal data collection, may improve our ability to define this connection and improve understanding of the biological risk factors underlying drusen development.
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Affiliation(s)
- Michael D Osterman
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland Ohio, United States.,Cleveland Institute for Computational Biology, Case Western Reserve University, Cleveland, Ohio, United States
| | - Yeunjoo E Song
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland Ohio, United States
| | - Muneeswar Nittala
- Doheny Imaging Reading Center, Doheny Eye Institute, Los Angeles, California, United States
| | - SriniVas R Sadda
- Doheny Imaging Reading Center, Doheny Eye Institute, Los Angeles, California, United States
| | - William K Scott
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, United States.,The Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, Florida, United States
| | - Dwight Stambolian
- Ophthalmology and Genetics, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Margaret A Pericak-Vance
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, United States.,The Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, Florida, United States
| | - Jonathan L Haines
- Department of Population and Quantitative Health Sciences, Case Western Reserve University, Cleveland Ohio, United States.,Cleveland Institute for Computational Biology, Case Western Reserve University, Cleveland, Ohio, United States
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Dykstra PB, Kaplan M, Smolke CD. Engineering synthetic RNA devices for cell control. Nat Rev Genet 2022; 23:215-228. [PMID: 34983970 PMCID: PMC9554294 DOI: 10.1038/s41576-021-00436-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/15/2021] [Indexed: 12/16/2022]
Abstract
The versatility of RNA in sensing and interacting with small molecules, proteins and other nucleic acids while encoding genetic instructions for protein translation makes it a powerful substrate for engineering biological systems. RNA devices integrate cellular information sensing, processing and actuation of specific signals into defined functions and have yielded programmable biological systems and novel therapeutics of increasing sophistication. However, challenges centred on expanding the range of analytes that can be sensed and adding new mechanisms of action have hindered the full realization of the field's promise. Here, we describe recent advances that address these limitations and point to a significant maturation of synthetic RNA-based devices.
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Affiliation(s)
- Peter B. Dykstra
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Matias Kaplan
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Christina D. Smolke
- Department of Bioengineering, Stanford University, Stanford, CA, USA.,Chan Zuckerberg Biohub, San Francisco, CA, USA.,
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24
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She K, Su J, Wang Q, Liu Y, Zhong X, Jin X, Zhao Q, Xiao J, Li R, Deng H, Lu F, Yang Y, Wei Y. Delivery of nVEGFi using AAV8 for the treatment of neovascular age-related macular degeneration. Mol Ther Methods Clin Dev 2022; 24:210-221. [PMID: 35141350 PMCID: PMC8800040 DOI: 10.1016/j.omtm.2022.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 01/05/2022] [Indexed: 11/01/2022]
Abstract
Inhibition of vascular endothelial growth factor (VEGF) is the standard therapy for neovascular age-related macular degeneration (nAMD). However, anti-VEGF agents used in the clinic require repeated injections, causing adverse effects. Gene therapy could provide sustained anti-VEGF levels after a single injection, thereby drastically decreasing the treatment burden and improving visual outcomes. In this study, we developed a novel VEGF Trap, nVEGFi, containing domains 1 and 2 of VEGFR1 and domain 3 of VEGFR2 fused to the Fc portion of human IgG. The nVEGFi had a higher expression level than aflibercept under the same expression cassettes of adeno-associated virus (AAV)8 in vitro and in vivo. nVEGFi was found to be noninferior to aflibercept in binding and blocking VEGF in vitro. AAV8-mediated expression of nVEGFi was maintained for at least 12 weeks by subretinal delivery in C57BL/6J mice. In a mouse laser-induced choroidal neovascularization (CNV) model, 4 × 108 genome copies of AAV8-nVEGFi exhibited a significantly increased reduction in the CNV area compared with AAV8-aflibercept (78.1% vs. 63.9%, p < 0.05), while causing no structural or functional changes to the retina. In conclusion, this preclinical study showed that subretinal injection of AAV8-nVEGFi was long lasting, well tolerated, and effective for nAMD treatment, supporting future translation to the clinic.
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Affiliation(s)
- Kaiqin She
- Department of Ophthalmology, West China Hospital, Sichuan University, No.37, Guoxue Xiang, Chengdu, Sichuan 610041, China.,State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Jing Su
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Qingnan Wang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Yi Liu
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Xiaomei Zhong
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Xiu Jin
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Qinyu Zhao
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Jianlu Xiao
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Ruiting Li
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Hongxin Deng
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Fang Lu
- Department of Ophthalmology, West China Hospital, Sichuan University, No.37, Guoxue Xiang, Chengdu, Sichuan 610041, China
| | - Yang Yang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
| | - Yuquan Wei
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center, No. 1, Ke-yuan Road 4, Gao-peng Street, Chengdu, Sichuan 610041, China
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25
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Takahashi K, Iida T, Ishida S, Crawford B, Sakai Y, Mochizuki A, Tsujiuchi R, Tanaka S, Imai K. Effectiveness of Current Treatments for Wet Age-Related Macular Degeneration in Japan: A Systematic Review and Pooled Data Analysis. Clin Ophthalmol 2022; 16:531-540. [PMID: 35250261 PMCID: PMC8888332 DOI: 10.2147/opth.s345403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 02/04/2022] [Indexed: 12/12/2022] Open
Abstract
Purpose We conducted a systematic review to investigate the effectiveness of clinical treatments for wet age-related macular degeneration (wAMD) in Japanese patients in the decade since anti-vascular endothelial growth factor (VEGF) therapies were introduced. Methods PubMed was searched for articles published in English between 1 January 2008 and 30 September 2018 using a multistring search strategy. Reviews were scanned for additional relevant studies and select gray literature was evaluated. Mean and/or median for the logarithm of the minimum angle of resolution (logMAR) visual acuity (VA), central retinal thickness (CRT), and the number of injections after 12 months of treatment were calculated using extracted data. Data were stratified by disease type and treatment modality. Results Of 335 studies identified, 94 were selected for data extraction (147 treatment arms; typical AMD, n = 25; polypoidal choroidal vasculopathy [PCV], n = 85). Mean (median) logMAR VA was 0.44 (0.32) for typical AMD and 0.34 (0.31) for PCV; the respective mean number of anti-VEGF injections was 5.6 and 4.6. The mean CRT was approximately 220 μm for both groups. For typical AMD, anti-VEGF monotherapy resulted in better VA outcomes than photodynamic therapy (PDT) alone. For PCV, anti-VEGF monotherapy or anti-VEGF plus PDT combination therapy resulted in better VA and CRT outcomes than PDT monotherapy. Combination therapy required fewer injections than anti-VEGF monotherapy (PCV, 3.2 versus 5.3). Conclusion wAMD treatment has advanced dramatically in the years since anti-VEGF drugs were introduced in Japan. Discrete patient populations may benefit from differing management regimens, including the fewer injections required with combination therapy.
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Affiliation(s)
- Kanji Takahashi
- Department of Ophthalmology, Kansai Medical University, Hirakata, Osaka, Japan
| | - Tomohiro Iida
- Department of Ophthalmology, Tokyo Women’s Medical University, Shinjuku, Tokyo, Japan
| | - Susumu Ishida
- Department of Ophthalmology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | | | - Yoko Sakai
- Syneos Health Clinical K.K., Chuo-ku, Tokyo, Japan
| | - Akikazu Mochizuki
- Novartis Pharma K.K., Minato-ku, Tokyo, Japan
- Correspondence: Akikazu Mochizuki, Novartis Pharma K.K., 23-1, Toranomon 1-chome, Minato-ku, Tokyo, Japan, Tel +81 3 6899 8000, Fax +81 3 6257 3634, Email
| | | | | | - Kota Imai
- Novartis Pharma K.K., Minato-ku, Tokyo, Japan
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26
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Eriksson RAE, Nieminen T, Galibert L, Peltola SK, Tikkanen P, Käyhty P, Lesch HP, Ylä-Herttuala S, Airenne KJ. Optimized riboswitch-regulated AAV vector for VEGF-B gene therapy. Front Med (Lausanne) 2022; 9:1052318. [PMID: 36582287 PMCID: PMC9792491 DOI: 10.3389/fmed.2022.1052318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 11/24/2022] [Indexed: 12/15/2022] Open
Abstract
Gene therapy would greatly benefit from a method to regulate therapeutic gene expression temporally. Riboswitches are small RNA elements that have been studied for their potential use in turning transgene expression on or off by ligand binding. We compared several tetracycline and toyocamycin-inducible ON-riboswitches for a drug responsive transgene expression. The tetracycline-dependent K19 riboswitch showed the best control and we successfully applied it to different transgenes. The induction of gene expression was 6- to 10-fold, dose-dependent, reversible, and occurred within hours after the addition of a clinically relevant tetracycline dose, using either plasmid or adeno-associated virus (AAV) vectors. To enhance the switching capacity, we further optimized the gene cassette to control the expression of a potential therapeutic gene for cardiovascular diseases, VEGF-B. Using two or three riboswitches simultaneously reduced leakiness and improved the dynamic range, and a linker sequence between the riboswitches improved their functionality. The riboswitch function was promoter-independent, but a post-transcriptional WPRE element in the expression cassette reduced its functionality. The optimized construct was a dual riboswitch at the 3' end of the transgene with a 100 bp linker sequence. Our study reveals significant differences in the function of riboswitches and provides important aspects on optimizing expression cassette designs. The findings will benefit further research and development of riboswitches.
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Affiliation(s)
- Reetta A E Eriksson
- Kuopio Center for Gene and Cell Therapy, Kuopio, Finland.,A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Tiina Nieminen
- Kuopio Center for Gene and Cell Therapy, Kuopio, Finland
| | | | | | - Petra Tikkanen
- Kuopio Center for Gene and Cell Therapy, Kuopio, Finland
| | - Piia Käyhty
- Kuopio Center for Gene and Cell Therapy, Kuopio, Finland.,A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Hanna P Lesch
- Kuopio Center for Gene and Cell Therapy, Kuopio, Finland
| | - Seppo Ylä-Herttuala
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.,Gene Therapy Unit and Research Center, Kuopio University Hospital, Kuopio, Finland
| | - Kari J Airenne
- Kuopio Center for Gene and Cell Therapy, Kuopio, Finland
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27
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Synthetic anti-angiogenic genomic therapeutics for treatment of neovascular age-related macular degeneration. Asian J Pharm Sci 2021; 16:623-632. [PMID: 34849167 PMCID: PMC8609386 DOI: 10.1016/j.ajps.2021.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 11/22/2022] Open
Abstract
In light of the intriguing potential of anti-angiogenic approach in suppressing choroidal neovascularization, we attempted to elaborate synthetic gene delivery systems encapsulating anti-angiogenic plasmid DNA as alternatives of clinical antibody-based therapeutics. Herein, block copolymer of cyclic Arg-Gly-Asp-poly(ethylene glycol)-poly(lysine-thiol) [RGD-PEG-PLys(thiol)] with multifunctional components was tailored in manufacture of core-shell DNA delivery nanoparticulates. Note that the polycationic PLys segments were electrostatically complexed with anionic plasmid DNA into nanoscaled core, and the tethered biocompatible PEG segments presented as the spatial shell (minimizing non-specific reactions in biological milieu). Furthermore, the aforementioned self-assembly was introduced with redox-responsive disulfide crosslinking due to the thiol coupling. Hence, reversible stabilities, namely stable in extracellular milieu but susceptible to disassemble for liberation of the DNA payloads in intracellular reducing microenvironment, were verified to facilitate transcellular gene transportation. In addition, RGD was installed onto the surface of the proposed self-assemblies with aim of targeted accumulation and internalization into angiogenic endothelial cells given that RGD receptors were specifically overexpressed on their cytomembrane surface. The proposed anti-angiogenic DNA therapeutics were validated to exert efficient expression of anti-angiogenic proteins in endothelial cells and elicit potent inhibition of ocular neovasculature post intravitreous administration. Hence, the present study approved the potential of gene therapy in treatment of choroidal neovascularization. In light of sustainable gene expression properties of DNA therapeutics, our proposed synthetic gene delivery system inspired prosperous potentials in long-term treatment of choroidal neovascularization, which should be emphasized to develop further towards clinical translations.
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28
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Finke M, Brecht D, Stifel J, Gense K, Gamerdinger M, Hartig JS. Efficient splicing-based RNA regulators for tetracycline-inducible gene expression in human cell culture and C. elegans. Nucleic Acids Res 2021; 49:e71. [PMID: 33893804 PMCID: PMC8266659 DOI: 10.1093/nar/gkab233] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/17/2021] [Accepted: 04/23/2021] [Indexed: 01/07/2023] Open
Abstract
Synthetic riboswitches gain increasing interest for controlling transgene expression in diverse applications ranging from synthetic biology, functional genomics, and pharmaceutical target validation to potential therapeutic approaches. However, existing systems often lack the pharmaceutically suited ligands and dynamic responses needed for advanced applications. Here we present a series of synthetic riboswitches for controlling gene expression through the regulation of alternative splicing. Placing the 5′-splice site into a stem structure of a tetracycline-sensing aptamer allows us to regulate the accessibility of the splice site. In the presence of tetracycline, an exon with a premature termination codon is skipped and gene expression can occur, whereas in its absence the exon is included into the coding sequence, repressing functional protein expression. We were able to identify RNA switches controlling protein expression in human cells with high dynamic ranges and different levels of protein expression. We present minimalistic versions of this system that circumvent the need to insert an additional exon. Further, we demonstrate the robustness of our approach by transferring the devices into the important research model organism Caenorhabditis elegans, where high levels of functional protein with very low background expression could be achieved.
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Affiliation(s)
- Monika Finke
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Dominik Brecht
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Julia Stifel
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Karina Gense
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.,Department of Biology, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Martin Gamerdinger
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.,Department of Biology, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Jörg S Hartig
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
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29
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Brinks J, van Dijk EHC, Klaassen I, Schlingemann RO, Kielbasa SM, Emri E, Quax PHA, Bergen AA, Meijer OC, Boon CJF. Exploring the choroidal vascular labyrinth and its molecular and structural roles in health and disease. Prog Retin Eye Res 2021; 87:100994. [PMID: 34280556 DOI: 10.1016/j.preteyeres.2021.100994] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 07/04/2021] [Accepted: 07/07/2021] [Indexed: 12/14/2022]
Abstract
The choroid is a key player in maintaining ocular homeostasis and plays a role in a variety of chorioretinal diseases, many of which are poorly understood. Recent advances in the field of single-cell RNA sequencing have yielded valuable insights into the properties of choroidal endothelial cells (CECs). Here, we review the role of the choroid in various physiological and pathophysiological mechanisms, focusing on the role of CECs. We also discuss new insights regarding the phenotypic properties of CECs, CEC subpopulations, and the value of measuring transcriptomics in primary CEC cultures derived from post-mortem eyes. In addition, we discuss key phenotypic, structural, and functional differences that distinguish CECs from other endothelial cells such as retinal vascular endothelial cells. Understanding the specific clinical and molecular properties of the choroid will shed new light on the pathogenesis of the broad clinical range of chorioretinal diseases such as age-related macular degeneration, central serous chorioretinopathy and other diseases within the pachychoroid spectrum, uveitis, and diabetic choroidopathy. Although our knowledge is still relatively limited with respect to the clinical features and molecular pathways that underlie these chorioretinal diseases, we summarise new approaches and discuss future directions for gaining new insights into these sight-threatening diseases and highlight new therapeutic strategies such as pluripotent stem cell‒based technologies and gene therapy.
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Affiliation(s)
- J Brinks
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - E H C van Dijk
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - I Klaassen
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - R O Schlingemann
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands; Department of Ophthalmology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands; Department of Ophthalmology, University of Lausanne, Jules Gonin Eye Hospital, Fondation Asile des Aveugles, Lausanne, Switzerland
| | - S M Kielbasa
- Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden, the Netherlands
| | - E Emri
- Department of Clinical Genetics, Section of Ophthalmogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - P H A Quax
- Department of Vascular Surgery, Leiden University Medical Center, Leiden, the Netherlands; Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - A A Bergen
- Department of Clinical Genetics, Section of Ophthalmogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - O C Meijer
- Department of Medicine, Division of Endocrinology and Metabolism, Leiden University Medical Center, Leiden, the Netherlands
| | - C J F Boon
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands; Department of Ophthalmology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands.
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31
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Ciulla T, Pennesi ME, Kiss S, Cunningham ET. DNA- and RNA-based Gene Therapies in Ophthalmology. Int Ophthalmol Clin 2021; 61:3-16. [PMID: 34196315 DOI: 10.1097/iio.0000000000000359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Tickner ZJ, Farzan M. Riboswitches for Controlled Expression of Therapeutic Transgenes Delivered by Adeno-Associated Viral Vectors. Pharmaceuticals (Basel) 2021; 14:ph14060554. [PMID: 34200913 PMCID: PMC8230432 DOI: 10.3390/ph14060554] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 05/28/2021] [Accepted: 06/04/2021] [Indexed: 11/16/2022] Open
Abstract
Vectors developed from adeno-associated virus (AAV) are powerful tools for in vivo transgene delivery in both humans and animal models, and several AAV-delivered gene therapies are currently approved for clinical use. However, AAV-mediated gene therapy still faces several challenges, including limited vector packaging capacity and the need for a safe, effective method for controlling transgene expression during and after delivery. Riboswitches, RNA elements which control gene expression in response to ligand binding, are attractive candidates for regulating expression of AAV-delivered transgene therapeutics because of their small genomic footprints and non-immunogenicity compared to protein-based expression control systems. In addition, the ligand-sensing aptamer domains of many riboswitches can be exchanged in a modular fashion to allow regulation by a variety of small molecules, proteins, and oligonucleotides. Riboswitches have been used to regulate AAV-delivered transgene therapeutics in animal models, and recently developed screening and selection methods allow rapid isolation of riboswitches with novel ligands and improved performance in mammalian cells. This review discusses the advantages of riboswitches in the context of AAV-delivered gene therapy, the subsets of riboswitch mechanisms which have been shown to function in human cells and animal models, recent progress in riboswitch isolation and optimization, and several examples of AAV-delivered therapeutic systems which might be improved by riboswitch regulation.
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Affiliation(s)
- Zachary J. Tickner
- Department of Immunology and Microbiology, the Scripps Research Institute, Jupiter, FL 33458, USA;
- Correspondence:
| | - Michael Farzan
- Department of Immunology and Microbiology, the Scripps Research Institute, Jupiter, FL 33458, USA;
- Emmune, Inc., Jupiter, FL 33458, USA
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Koponen S, Kokki E, Kinnunen K, Ylä-Herttuala S. Viral-Vector-Delivered Anti-Angiogenic Therapies to the Eye. Pharmaceutics 2021; 13:pharmaceutics13020219. [PMID: 33562561 PMCID: PMC7915489 DOI: 10.3390/pharmaceutics13020219] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/31/2021] [Accepted: 02/02/2021] [Indexed: 12/17/2022] Open
Abstract
Pathological vessel growth harms vision and may finally lead to vision loss. Anti-angiogenic gene therapy with viral vectors for ocular neovascularization has shown great promise in preclinical studies. Most of the studies have been conducted with different adeno-associated serotype vectors. In addition, adeno- and lentivirus vectors have been used. Therapy has been targeted towards blocking vascular endothelial growth factors or other pro-angiogenic factors. Clinical trials of intraocular gene therapy for neovascularization have shown the treatment to be safe without severe adverse events or systemic effects. Nevertheless, clinical studies have not proceeded further than Phase 2 trials.
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Affiliation(s)
- Sanna Koponen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland; (S.K.); (E.K.)
| | - Emmi Kokki
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland; (S.K.); (E.K.)
| | - Kati Kinnunen
- Department of Ophthalmology, Kuopio University Hospital, 70211 Kuopio, Finland;
| | - Seppo Ylä-Herttuala
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland; (S.K.); (E.K.)
- Gene Therapy Unit, Kuopio University Hospital, 70211 Kuopio, Finland
- Correspondence: ; Tel./Fax: +358-403-552-075
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Díaz-Lezama N, Wolf A, Koch S, Pfaller AM, Biber J, Guillonneau X, Langmann T, Grosche A. PDGF Receptor Alpha Signaling Is Key for Müller Cell Homeostasis Functions. Int J Mol Sci 2021; 22:ijms22031174. [PMID: 33503976 PMCID: PMC7865899 DOI: 10.3390/ijms22031174] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/21/2021] [Accepted: 01/21/2021] [Indexed: 01/09/2023] Open
Abstract
Müller cells, the major retinal macroglia, are key to maintaining vascular integrity as well as retinal fluid and ion homeostasis. Although platelet derived growth factor (PDGF) receptor expression in Müller glia has been reported earlier, their actual role for Müller cell function and intimate interaction with cells of the retinal neurovascular unit remains unclear. To close this gap of knowledge, Müller cell-specific PDGF receptor alpha (PDGFRα) knockout (KO) mice were generated, characterized, and subjected to a model of choroidal neovascularization (CNV). PDGFRα-deficient Müller cells could not counterbalance hypoosmotic stress as efficiently as their wildtype counterparts. In wildtypes, the PDGFRα ligand PDGF-BB prevented Müller cell swelling induced by the administration of barium ions. This effect could be blocked by the PDGFR family inhibitor AC710. PDGF-BB could not restore the capability of an efficient volume regulation in PDGFRα KO Müller cells. Additionally, PDGFRα KO mice displayed reduced rod and cone-driven light responses. Altogether, these findings suggest that Müller glial PDGFRα is central for retinal functions under physiological conditions. In contrast, Müller cell-specific PDGFRα KO resulted in less vascular leakage and smaller lesion areas in the CNV model. Of note, the effect size was comparable to pharmacological blockade of PDGF signaling alone or in combination with anti-vascular endothelial growth factor (VEGF) therapy—a treatment regimen currently being tested in clinical trials. These data imply that targeting PDGF to treat retinal neovascular diseases may have short-term beneficial effects, but may elicit unwarranted side effects given the putative negative effects on Müller cell homeostatic functions potentially interfering with a long-term positive outcome.
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Affiliation(s)
- Nundehui Díaz-Lezama
- Department of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, D-82152 Planegg-Martinsried, Germany; (N.D.-L.); (S.K.); (A.M.P.); (J.B.)
| | - Anne Wolf
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, D-50931 Cologne, Germany; (A.W.); (T.L.)
| | - Susanne Koch
- Department of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, D-82152 Planegg-Martinsried, Germany; (N.D.-L.); (S.K.); (A.M.P.); (J.B.)
| | - Anna M. Pfaller
- Department of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, D-82152 Planegg-Martinsried, Germany; (N.D.-L.); (S.K.); (A.M.P.); (J.B.)
| | - Josef Biber
- Department of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, D-82152 Planegg-Martinsried, Germany; (N.D.-L.); (S.K.); (A.M.P.); (J.B.)
| | - Xavier Guillonneau
- Institut de la Vision, INSERM, CNRS, Sorbonne Université, F-75012 Paris, France;
| | - Thomas Langmann
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, D-50931 Cologne, Germany; (A.W.); (T.L.)
| | - Antje Grosche
- Department of Physiological Genomics, Biomedical Center, Ludwig-Maximilians-Universität München, D-82152 Planegg-Martinsried, Germany; (N.D.-L.); (S.K.); (A.M.P.); (J.B.)
- Correspondence:
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Spöring M, Boneberg R, Hartig JS. Aptamer-Mediated Control of Polyadenylation for Gene Expression Regulation in Mammalian Cells. ACS Synth Biol 2020; 9:3008-3018. [PMID: 33108164 DOI: 10.1021/acssynbio.0c00222] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Small aptamer-based regulatory devices can be designed to control a range of RNA-dependent cellular processes and emerged as promising tools for fine-tuning gene expression in synthetic biology. Here, we design a conceptually new riboswitch device that allows for the conditional regulation of polyadenylation. By making use of ligand-induced sequence occlusion, the system efficiently controls the accessibility of the eukaryotic polyadenylation signal. Undesirable 3'-extended read-through products are counteracted by the downstream insertion of a microRNA target site. We demonstrate the modularity of the system with regard to sensor aptamers and polyadenylation signals used and combine the newly designed riboswitch with well-known aptazymes to yield superior composite systems. In addition, we show that the switches can be used to control alternative polyadenylation. The presented genetic switches require very little coding space and can be easily optimized by rational adjustments of the thermodynamic stability. The polyadenylation riboswitch extends the repertoire of RNA-based regulators and opens new possibilities for the generation of complex synthetic circuits.
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Affiliation(s)
- Maike Spöring
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
- Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Ronja Boneberg
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Jörg S. Hartig
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
- Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
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Berkowitz ST, Patel S. Value of Anti-Vascular Endothelial Growth Factor Gene Therapy for Neovascular Age-Related Macular Degeneration. Ophthalmol Retina 2020; 5:357-364. [PMID: 32818623 DOI: 10.1016/j.oret.2020.08.005] [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: 05/10/2020] [Revised: 08/06/2020] [Accepted: 08/10/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE To use discounted cash flow (DCF) analysis to estimate the value creation associated with anti-vascular endothelial growth factor (VEGF) genetic therapy for neovascular age-related macular degeneration (nAMD). DESIGN Economic analysis. PARTICIPANTS Adults undergoing serial intravitreal anti-VEGF injections in 1 eye for nAMD. METHODS Discounted cash flow modeling with scenario analysis was used to derive a present value for a 1-time alternative treatment to lifelong anti-VEGF treatment for nAMD. Multiple sensitivity analyses were performed on the basis of patient age at time of first injection and frequency interval of intravitreal injection. MAIN OUTCOME MEASURES Present values of DCF and scenario analyses. RESULTS Discounted cash flow analysis of intravitreal anti-VEGF treatment for nAMD resulted in a base-case valuation of $208 420.61, $219 093.31, and $17 379.41 for a 1-time alternative treatment to aflibercept, ranibizumab, and bevacizumab, respectively. This figure covaried significantly with anti-VEGF agent according to the patient age at first injection ($78 323.19-$292 449.87) and frequency of injections ($148 422.91-$388 096.81). In addition, for bevacizumab, variability was driven by the hypothetical degree of clinical superiority of 1-time therapy to repeated intravitreal injections due to reduction in adverse events ($17 379.41-$18 250.79) or reduction in direct or indirect costs associated with age-related macular degeneration ($17 379.41-$657 406.55). CONCLUSIONS Anti-VEGF gene therapy approaches can create significantly different value propositions based on the agent modeled, patient age at first injection, frequency of injections, and clinical profile of the medication. Although the use of aflibercept or ranibizumab as a comparative cost metric is logical from a bioequivalence perspective, the disparity in medication costs should not be the primary value driver in applied models. Instead, bevacizumab should be the base case ($17 379.41), with additional value driven from an improvement in quality of life through clinical superiority. A reduction in direct and indirect costs can be used to approximate the value from maintained visual acuity, which is elaborated in the DCF analysis approach described in this article. This model can serve as a basis for assessing the price ceiling of myriad gene therapy approaches. Given the high present values for these therapeutics, innovative costing and reimbursement mechanisms should be further explored, with contingencies for sustained efficacy.
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Affiliation(s)
- Sean T Berkowitz
- Department of Ophthalmology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Shriji Patel
- Department of Ophthalmology, Vanderbilt University School of Medicine, Nashville, Tennessee.
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Strobel B, Düchs MJ, Blazevic D, Rechtsteiner P, Braun C, Baum-Kroker KS, Schmid B, Ciossek T, Gottschling D, Hartig JS, Kreuz S. A Small-Molecule-Responsive Riboswitch Enables Conditional Induction of Viral Vector-Mediated Gene Expression in Mice. ACS Synth Biol 2020; 9:1292-1305. [PMID: 32427483 DOI: 10.1021/acssynbio.9b00410] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Adeno-associated viral (AAV) vector-mediated gene therapy holds great potential for future medical applications. However, to facilitate safer and broader applicability and to enable patient-centric care, therapeutic protein expression should be controllable, ideally by an orally administered drug. The use of protein-based systems is considered rather undesirable, due to potential immunogenicity and the limited coding space of AAV. Ligand-dependent riboswitches, in contrast, are small and characterized by an attractive mode-of-action based on mRNA-self-cleavage, independent of coexpressed foreign protein. While a promising approach, switches available to date have only shown moderate potency in animals. In particular, ON-switches that induce transgene expression upon ligand administration so far have achieved rather disappointing results. Here we present the utilization of the previously described tetracycline-dependent ribozyme K19 for controlling AAV-mediated transgene expression in mice. Using this tool switch, we provide first proof for the feasibility of clinically desired key features, including multiorgan functionality, potent regulation (up to 15-fold induction), reversibility, and the possibility to fine-tune and repeatedly induce expression. The systematic assessment of ligand and reporter protein plasma levels further enabled the characterization of pharmacokinetic-pharmacodynamic relationships. Thus, our results strongly support future efforts to develop engineered riboswitches for applications in clinical gene therapy.
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Affiliation(s)
- Benjamin Strobel
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Matthias J. Düchs
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Dragica Blazevic
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Philipp Rechtsteiner
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Clemens Braun
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Katja S. Baum-Kroker
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Bernhard Schmid
- Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Thomas Ciossek
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Dirk Gottschling
- Medicinal Chemistry, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
| | - Jörg S. Hartig
- Department of Chemistry, University of Konstanz, Konstanz, 78464, Germany
| | - Sebastian Kreuz
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, 88397, Germany
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Buck TM, Wijnholds J. Recombinant Adeno-Associated Viral Vectors (rAAV)-Vector Elements in Ocular Gene Therapy Clinical Trials and Transgene Expression and Bioactivity Assays. Int J Mol Sci 2020; 21:E4197. [PMID: 32545533 PMCID: PMC7352801 DOI: 10.3390/ijms21124197] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 02/06/2023] Open
Abstract
Inherited retinal dystrophies and optic neuropathies cause chronic disabling loss of visual function. The development of recombinant adeno-associated viral vectors (rAAV) gene therapies in all disease fields have been promising, but the translation to the clinic has been slow. The safety and efficacy profiles of rAAV are linked to the dose of applied vectors. DNA changes in the rAAV gene cassette affect potency, the expression pattern (cell-specificity), and the production yield. Here, we present a library of rAAV vectors and elements that provide a workflow to design novel vectors. We first performed a meta-analysis on recombinant rAAV elements in clinical trials (2007-2020) for ocular gene therapies. We analyzed 33 unique rAAV gene cassettes used in 57 ocular clinical trials. The rAAV gene therapy vectors used six unique capsid variants, 16 different promoters, and six unique polyadenylation sequences. Further, we compiled a list of promoters, enhancers, and other sequences used in current rAAV gene cassettes in preclinical studies. Then, we give an update on pro-viral plasmid backbones used to produce the gene therapy vectors, inverted terminal repeats, production yield, and rAAV safety considerations. Finally, we assess rAAV transgene and bioactivity assays applied to cells or organoids in vitro, explants ex vivo, and clinical studies.
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Affiliation(s)
- Thilo M. Buck
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZC Leiden, The Netherlands;
| | - Jan Wijnholds
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZC Leiden, The Netherlands;
- Netherlands Institute of Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), 1105 BA Amsterdam, The Netherlands
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The retina revolution: signaling pathway therapies, genetic therapies, mitochondrial therapies, artificial intelligence. Curr Opin Ophthalmol 2020; 31:207-214. [PMID: 32205471 DOI: 10.1097/icu.0000000000000656] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE OF REVIEW The aim of this article is to review and discuss the history, current state, and future implications of promising biomedical offerings in the field of retina. RECENT FINDINGS The technologies discussed are some of the more recent promising biomedical developments within the field of retina. There is a US Food and Drug Administration-approved gene therapy product and artificial intelligence device for retina, with many other offerings in the pipeline. SUMMARY Signaling pathway therapies, genetic therapies, mitochondrial therapies, and artificial intelligence have shaped retina care as we know it and are poised to further impact the future of retina care. Retina specialists have the privilege and responsibility of shaping this future for the visual health of current and future generations.
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40
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Wrist A, Sun W, Summers RM. The Theophylline Aptamer: 25 Years as an Important Tool in Cellular Engineering Research. ACS Synth Biol 2020; 9:682-697. [PMID: 32142605 DOI: 10.1021/acssynbio.9b00475] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The theophylline aptamer was isolated from an oligonucleotide library in 1994. Since that time, the aptamer has found wide utility, particularly in synthetic biology, cellular engineering, and diagnostic applications. The primary application of the theophylline aptamer is in the construction and characterization of synthetic riboswitches for regulation of gene expression. These riboswitches have been used to control cellular motility, regulate carbon metabolism, construct logic gates, screen for mutant enzymes, and control apoptosis. Other applications of the theophylline aptamer in cellular engineering include regulation of RNA interference and genome editing through CRISPR systems. Here we describe the uses of the theophylline aptamer for cellular engineering over the past 25 years. In so doing, we also highlight important synthetic biology applications to control gene expression in a ligand-dependent manner.
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Affiliation(s)
- Alexandra Wrist
- Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Wanqi Sun
- Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama 35487, United States
| | - Ryan M. Summers
- Department of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama 35487, United States
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Strobel B, Spöring M, Klein H, Blazevic D, Rust W, Sayols S, Hartig JS, Kreuz S. High-throughput identification of synthetic riboswitches by barcode-free amplicon-sequencing in human cells. Nat Commun 2020; 11:714. [PMID: 32024835 PMCID: PMC7002664 DOI: 10.1038/s41467-020-14491-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 01/14/2020] [Indexed: 11/10/2022] Open
Abstract
Synthetic riboswitches mediating ligand-dependent RNA cleavage or splicing-modulation represent elegant tools to control gene expression in various applications, including next-generation gene therapy. However, due to the limited understanding of context-dependent structure-function relationships, the identification of functional riboswitches requires large-scale-screening of aptamer-effector-domain designs, which is hampered by the lack of suitable cellular high-throughput methods. Here we describe a fast and broadly applicable method to functionally screen complex riboswitch libraries (~1.8 × 104 constructs) by cDNA-amplicon-sequencing in transiently transfected and stimulated human cells. The self-barcoding nature of each construct enables quantification of differential mRNA levels without additional pre-selection or cDNA-manipulation steps. We apply this method to engineer tetracycline- and guanine-responsive ON- and OFF-switches based on hammerhead, hepatitis-delta-virus and Twister ribozymes as well as U1-snRNP polyadenylation-dependent RNA devices. In summary, our method enables fast and efficient high-throughput riboswitch identification, thereby overcoming a major hurdle in the development cascade for therapeutically applicable gene switches.
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Affiliation(s)
- Benjamin Strobel
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, 88397, Biberach an der Riss, Germany
| | - Maike Spöring
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464, Konstanz, Germany
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78464, Konstanz, Germany
| | - Holger Klein
- Computational Biology & Genomics, Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, 88397, Biberach an der Riss, Germany
| | - Dragica Blazevic
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, 88397, Biberach an der Riss, Germany
| | - Werner Rust
- Computational Biology & Genomics, Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, 88397, Biberach an der Riss, Germany
| | - Sergi Sayols
- Computational Biology & Genomics, Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, 88397, Biberach an der Riss, Germany
| | - Jörg S Hartig
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78464, Konstanz, Germany
- Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78464, Konstanz, Germany
| | - Sebastian Kreuz
- Research Beyond Borders, Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Str. 65, 88397, Biberach an der Riss, Germany.
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Mustafina K, Fukunaga K, Yokobayashi Y. Design of Mammalian ON-Riboswitches Based on Tandemly Fused Aptamer and Ribozyme. ACS Synth Biol 2020; 9:19-25. [PMID: 31820936 DOI: 10.1021/acssynbio.9b00371] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Self-cleaving ribozymes engineered to be activated or inhibited by a small molecule binding to an RNA aptamer inserted within a ribozyme (aptazymes) have proven to be useful for controlling gene expression in living cells. In mammalian cells, an aptazyme embedded in the 5' or 3' untranslated region of an mRNA functions as a synthetic riboswitch to chemically regulate gene expression. However, the variety of aptazyme architectures and the ribozyme scaffolds that have been used for mammalian riboswitches has been limited. In particular, fewer synthetic riboswitches that activate gene expression in response to a small molecule (ON-switches) in mammalian cells have been reported compared to OFF-switches. In this work, we developed mammalian riboswitches that function as guanine-activated ON-switches based on a novel aptazyme architecture in which an aptamer and a ribozyme are fused in tandem. The riboswitch performance was optimized by fine-tuning the stability of a critical stem that controls the ribozyme structure and function, yielding switches with ON/OFF ratios greater than 6.0. Our new aptazyme architecture expands the RNA device toolbox for controlling gene expression in mammalian cells.
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Affiliation(s)
- Kamila Mustafina
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904 0495, Japan
| | - Keisuke Fukunaga
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904 0495, Japan
| | - Yohei Yokobayashi
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904 0495, Japan
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Spöring M, Finke M, Hartig JS. Aptamers in RNA-based switches of gene expression. Curr Opin Biotechnol 2019; 63:34-40. [PMID: 31811992 DOI: 10.1016/j.copbio.2019.11.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 11/04/2019] [Accepted: 11/06/2019] [Indexed: 01/25/2023]
Abstract
The ability to control gene expression via small molecule effectors is important in basic research as well as in future gene therapy applications. Although transcription factor-based systems are widely used, they are not well suited for certain applications due to a lack of functionality, limited available coding space, and potential immunogenicity of the regulatory proteins. RNA-based switches fill this gap since they can be designed to respond to effector compounds utilizing ligand-sensing aptamers. These systems are very modular since the aptamer can be combined with a variety of different expression platforms. RNA-based switches have been constructed that allow for controlling gene expression in diverse contexts. Here we discuss latest developments and applications of aptamer-based gene expression switches in eukaryotes.
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Affiliation(s)
- Maike Spöring
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany; Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Monika Finke
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany; Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Jörg S Hartig
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany; Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.
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Takahashi K, Yokobayashi Y. Reversible Gene Regulation in Mammalian Cells Using Riboswitch-Engineered Vesicular Stomatitis Virus Vector. ACS Synth Biol 2019; 8:1976-1982. [PMID: 31415142 DOI: 10.1021/acssynbio.9b00177] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Synthetic riboswitches based on small molecule-responsive self-cleaving ribozymes (aptazymes) embedded in the untranslated regions (UTRs) allow chemical control of gene expression in mammalian cells. In this work, we used a guanine-responsive aptazyme to control transgene expression from a replication-incompetent vesicular stomatitis virus (VSV) vector. VSV is a nonsegmented, negative-sense, cytoplasmic RNA virus that replicates without DNA intermediates, and its applications for vaccines and oncolytic viral therapy are being explored. By inserting the guanine-activated ribozyme in the 3' UTRs of viral genes and transgenes, GFP expression from the VSV vector in mammalian cells was repressed by as much as 26.8-fold in the presence of guanine. Furthermore, we demonstrated reversible regulation of a transgene (secreted NanoLuc) by adding and withdrawing guanine from the medium over the course of 12 days. In summary, our riboswitch-controlled VSV vector allows robust, long-term, and reversible regulation of gene expression in mammalian cells without the risk of undesirable genomic integration.
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Affiliation(s)
- Kei Takahashi
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904 0495, Japan
| | - Yohei Yokobayashi
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904 0495, Japan
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Wood EH, Tang PH, De la Huerta I, Korot E, Muscat S, Palanker DA, Williams GA. STEM CELL THERAPIES, GENE-BASED THERAPIES, OPTOGENETICS, AND RETINAL PROSTHETICS: Current State and Implications for the Future. Retina 2019; 39:820-835. [PMID: 30664120 PMCID: PMC6492547 DOI: 10.1097/iae.0000000000002449] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE To review and discuss current innovations and future implications of promising biotechnology and biomedical offerings in the field of retina. We focus on therapies that have already emerged as clinical offerings or are poised to do so. METHODS Literature review and commentary focusing on stem cell therapies, gene-based therapies, optogenetic therapies, and retinal prosthetic devices. RESULTS The technologies discussed herein are some of the more recent promising biotechnology and biomedical developments within the field of retina. Retinal prosthetic devices and gene-based therapies both have an FDA-approved product for ophthalmology, and many other offerings (including optogenetics) are in the pipeline. Stem cell therapies offer personalized medicine through novel regenerative mechanisms but entail complex ethical and reimbursement challenges. CONCLUSION Stem cell therapies, gene-based therapies, optogenetics, and retinal prosthetic devices represent a new era of biotechnological and biomedical progress. These bring new ethical, regulatory, care delivery, and reimbursement challenges. By addressing these issues proactively, we may accelerate delivery of care to patients in a safe, efficient, and value-based manner.
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Affiliation(s)
| | - Peter H Tang
- Department of Ophthalmology, Hansen Experimental Physics Laboratory, Stanford University, Stanford, California
| | | | - Edward Korot
- Oakland University William Beaumont School of Medicine, Rochester, Michigan
| | | | - Daniel A Palanker
- Department of Ophthalmology, Hansen Experimental Physics Laboratory, Stanford University, Stanford, California
| | - George A Williams
- Associated Retinal Consultants, Royal Oak, Michigan
- Oakland University William Beaumont School of Medicine, Rochester, Michigan
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A Comparison of Inducible Gene Expression Platforms: Implications for Recombinant Adeno-Associated Virus (rAAV) Vector-Mediated Ocular Gene Therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1185:79-83. [PMID: 31884592 DOI: 10.1007/978-3-030-27378-1_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The ability to temporally control levels of a therapeutic protein in vivo is vital for the development of safe and efficacious gene therapy treatments for autosomal dominant or complex retinal diseases, where uncontrolled transgene overexpression may lead to deleterious off-target effects and accelerated disease progression. While numerous platforms exist that allow for modulation of gene expression levels - ranging from inducible promoters to destabilizing domains - many have drawbacks that make them less than ideal for use in recombinant adeno-associated virus (rAAV) vectors, which over the past two decades have become the mainstay technology for mediating gene delivery to the retina. Herein, we discuss the advantages and disadvantages of three major gene expression platforms with regard to their suitability for ocular gene therapy applications.
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