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Greitens C, Leroux JC, Burger M. The intracellular visualization of exogenous DNA in fluorescence microscopy. Drug Deliv Transl Res 2024; 14:2242-2261. [PMID: 38526634 PMCID: PMC11208204 DOI: 10.1007/s13346-024-01563-4] [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] [Accepted: 02/28/2024] [Indexed: 03/27/2024]
Abstract
In the development of non-viral gene delivery vectors, it is essential to reliably localize and quantify transfected DNA inside the cell. To track DNA, fluorescence microscopy methods are commonly applied. These mostly rely on fluorescently labeled DNA, DNA binding proteins fused to a fluorescent protein, or fluorescence in situ hybridization (FISH). In addition, co-stainings are often used to determine the colocalization of the DNA in specific cellular compartments, such as the endolysosomes or the nucleus. We provide an overview of these DNA tracking methods, advice on how they should be combined, and indicate which co-stainings or additional methods are required to draw precise conclusions from a DNA tracking experiment. Some emphasis is given to the localization of exogenous DNA inside the nucleus, which is the last step of DNA delivery. We argue that suitable tools which allow for the nuclear detection of faint signals are still missing, hampering the rational development of more efficient non-viral transfection systems.
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Affiliation(s)
- Christina Greitens
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093, Zurich, Switzerland
| | - Jean-Christophe Leroux
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093, Zurich, Switzerland.
| | - Michael Burger
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093, Zurich, Switzerland.
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2
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Zhang H, Vandesompele J, Braeckmans K, De Smedt SC, Remaut K. Nucleic acid degradation as barrier to gene delivery: a guide to understand and overcome nuclease activity. Chem Soc Rev 2024; 53:317-360. [PMID: 38073448 DOI: 10.1039/d3cs00194f] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Gene therapy is on its way to revolutionize the treatment of both inherited and acquired diseases, by transferring nucleic acids to correct a disease-causing gene in the target cells of patients. In the fight against infectious diseases, mRNA-based therapeutics have proven to be a viable strategy in the recent Covid-19 pandemic. Although a growing number of gene therapies have been approved, the success rate is limited when compared to the large number of preclinical and clinical trials that have been/are being performed. In this review, we highlight some of the hurdles which gene therapies encounter after administration into the human body, with a focus on nucleic acid degradation by nucleases that are extremely abundant in mammalian organs, biological fluids as well as in subcellular compartments. We overview the available strategies to reduce the biodegradation of gene therapeutics after administration, including chemical modifications of the nucleic acids, encapsulation into vectors and co-administration with nuclease inhibitors and discuss which strategies are applied for clinically approved nucleic acid therapeutics. In the final part, we discuss the currently available methods and techniques to qualify and quantify the integrity of nucleic acids, with their own strengths and limitations.
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Affiliation(s)
- Heyang Zhang
- Laboratory for General Biochemistry and Physical Pharmacy, Department of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
- Leiden Academic Centre for Drug Research, Leiden University, 2333 CC Leiden, The Netherlands
| | - Jo Vandesompele
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
| | - Kevin Braeckmans
- Laboratory for General Biochemistry and Physical Pharmacy, Department of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
- Centre for Nano- and Biophotonics, Ghent University, 9000 Ghent, Belgium
| | - Stefaan C De Smedt
- Laboratory for General Biochemistry and Physical Pharmacy, Department of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
- Centre for Nano- and Biophotonics, Ghent University, 9000 Ghent, Belgium
| | - Katrien Remaut
- Laboratory for General Biochemistry and Physical Pharmacy, Department of Pharmaceutical Sciences, Ghent University, 9000 Ghent, Belgium.
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium
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3
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Senevirathne A, Park JY, Hewawaduge C, Perumalraja K, Lee JH. Eukaryotic expression system complemented with expressivity of Semliki Forest Virus's RdRp and invasiveness of engineered Salmonella demonstrate promising potential for bacteria mediated gene therapy. Biomaterials 2021; 279:121226. [PMID: 34736150 DOI: 10.1016/j.biomaterials.2021.121226] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 09/29/2021] [Accepted: 10/22/2021] [Indexed: 10/20/2022]
Abstract
This study describes an efficient eukaryotic expression system (pJHL204) built into the Salmonella delivery system to enhance the essential efficacy and effectiveness of conventional DNA therapy. The expression system utilizes RNA-dependent RNA polymerase activity (RdRp) of Semiliki Forest Virus attributing to dramatic antigen expression by cytoplasmic mRNA amplification. Functional characterization of the pJHL204 by in vitro and in vivo transfection studies revealed the improved expression of mRNA at least 150 folds than the RdRp mutant plasmid under in vitro conditions. Using green fluorescence protein (GFP) and mCherry as bait proteins this system was extensively characterized for plasmid delivery capacity, antigen expression, and safety using in vivo and in vitro models by employing flow cytometry, fluorescence microscopy, and immunohistochemical staining. Employment of Salmonella as a carrier significantly extends plasmid in vivo survivability and prolongs the effective duration until the elimination of the Salmonella carrier strain in the host. The strategy can be easily adapted for P2A connected multiple antigen delivery in a single vector system due to the significantly high cargo capacity of Salmonella. A mouse challenge study was carried out utilizing P2A connected H1N1 hemagglutinin (HA) and neuraminidase (NA) via the Salmonella carrier strain JOL2500 significantly reduced viral activity and protected mice against the H1N1 challenge and demonstrates potential to redefine in vivo DNA therapy as a reliable and safe system to treat human diseases using useful microbes like Salmonella.
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Affiliation(s)
- Amal Senevirathne
- College of Veterinary Medicine, Jeonbuk National University, Iksan Campus, 54596, Iksan, Republic of Korea
| | - Ji-Young Park
- College of Veterinary Medicine, Jeonbuk National University, Iksan Campus, 54596, Iksan, Republic of Korea
| | - Chamith Hewawaduge
- College of Veterinary Medicine, Jeonbuk National University, Iksan Campus, 54596, Iksan, Republic of Korea
| | - Kirthika Perumalraja
- College of Veterinary Medicine, Jeonbuk National University, Iksan Campus, 54596, Iksan, Republic of Korea
| | - John Hwa Lee
- College of Veterinary Medicine, Jeonbuk National University, Iksan Campus, 54596, Iksan, Republic of Korea.
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Karagyaur M, Rostovtseva A, Dzhauari S, Kozlov E, Lebedeva L, Klimovich P, Balabanyan V, Semina E, Sysoeva V, Shidlovskii Y, Popov V, Stambolsky D. Biodistribution and Safety Studies of a Bicistronic Plasmid for Nerve Repair. Tissue Eng Part C Methods 2021; 27:391-400. [PMID: 34015967 DOI: 10.1089/ten.tec.2021.0033] [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: 11/13/2022] Open
Abstract
Gene therapy is one of the promising approaches for regenerative medicine. Local and long-term expression of essential growth factors allows to achieve the desired therapeutic effect. However, some aspects of prolonged usage of genetic constructs encoding growth factors, such as toxicity, mutagenicity, genotoxicity, and ability to disseminate from the injection site and mediate ectopic expression of therapeutic proteins, are poorly investigated. These aspects of gene therapy drugs' usage became the subject of this study. To study plasmid biodistribution, toxicity, mutagenicity, and genotoxicity, we used previously described bicistronic genetic construct encoding human brain-derived neurotrophic factor (hBDNF) and human urokinase plasminogen activator (huPA) for nerve repair. Biodistribution studies were conducted in mice: a course of intramuscular plasmid injections was followed by the study of the content of the plasmid (real-time polymerase chain reaction) and recombinant proteins (enzyme-linked immunosorbent assay) in murine organs and tissues. The study of the plasmid chronic toxicity was carried out on rats with registration of their weight dynamics, neurological status, emotional state, and blood test parameters. The mutagenicity of the plasmid was studied in an in vivo DNA comet test in mice. Plasmid genotoxicity was investigated in the model of somatic recombination in Drosophila females. We have shown that plasmids can disseminate from the injection site, but do not mediate ectopic expression of growth factors upon repeated intramuscular injections. The studied plasmid also does not reveal toxic, mutagenic, or genotoxic effects. During the toxicological study on rats, we have shown that daily injections of this genetic construct, despite its ability to disseminate from the injection site, do not affect the physical, cognitive, and emotional state of experimental animals. We have demonstrated the safety of the bicistronic plasmid, encoding hBDNF and huPA, upon its repeated administration. The properties of genetic constructs strongly depend on their sequence and delivery approach, which requires conducting of their safety studies in each specific case. Impact statement Gene therapy is one of the promising approaches for regenerative medicine. Local and long-term expression of essential growth factors allows to achieve the desired therapeutic effect. However, some aspects of prolonged usage of genetic constructs encoding growth factors, such as toxicity, mutagenicity, genotoxicity, and ability to disseminate from the injection site and mediate ectopic expression of therapeutic proteins, are poorly investigated. These aspects of gene therapy became the subject of this study. To our knowledge, this is a unique study that provides a thorough safety investigation of a bicistronic plasmid after its readministration.
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Affiliation(s)
- Maxim Karagyaur
- Institute for Regenerative Medicine, Lomonosov Moscow State University, Moscow, Russia.,Faculty of Medicine, Lomonosov Moscow State University, Moscow, Russia
| | | | - Stalik Dzhauari
- Faculty of Medicine, Lomonosov Moscow State University, Moscow, Russia
| | - Eugene Kozlov
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Lyubov Lebedeva
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Polina Klimovich
- Faculty of Medicine, Lomonosov Moscow State University, Moscow, Russia
| | - Vadim Balabanyan
- Faculty of Medicine, Lomonosov Moscow State University, Moscow, Russia
| | - Ekaterina Semina
- Faculty of Medicine, Lomonosov Moscow State University, Moscow, Russia.,Molecular Endocrinology Lab, Institute of Experimental Cardiology, National Cardiology Research Center Ministry of Health of the Russian Federation, Moscow, Russia
| | - Veronika Sysoeva
- Faculty of Medicine, Lomonosov Moscow State University, Moscow, Russia
| | - Yulii Shidlovskii
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia.,Department of Biology and General Genetics, I.M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Vladimir Popov
- Faculty of Medicine, Lomonosov Moscow State University, Moscow, Russia
| | - Dmitry Stambolsky
- Medical Research and Education Center, Lomonosov Moscow State University, Moscow, Russia
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5
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Chen Y, Aslanoglou S, Gervinskas G, Abdelmaksoud H, Voelcker NH, Elnathan R. Cellular Deformations Induced by Conical Silicon Nanowire Arrays Facilitate Gene Delivery. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1904819. [PMID: 31599099 DOI: 10.1002/smll.201904819] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 09/29/2019] [Indexed: 06/10/2023]
Abstract
Engineered cell-nanostructured interfaces generated by vertically aligned silicon nanowire (SiNW) arrays have become a promising platform for orchestrating cell behavior, function, and fate. However, the underlying mechanism in SiNW-mediated intracellular access and delivery is still poorly understood. This study demonstrates the development of a gene delivery platform based on conical SiNW arrays for mechanical cell transfection, assisted by centrifugal force, for both adherent and nonadherent cells in vitro. Cells form focal adhesions on SiNWs within 6 h, and maintain high viability and motility. Such a functional and dynamic cell-SiNW interface features conformational changes in the plasma membrane and in some cases the nucleus, promoting both direct penetration and endocytosis; this synergistically facilitates SiNW-mediated delivery of nucleic acids into immortalized cell lines, and into difficult-to-transfect primary immune T cells without pre-activation. Moreover, transfected cells retrieved from SiNWs retain the capacity to proliferate-crucial to future biomedical applications. The results indicate that SiNW-mediated intracellular delivery holds great promise for developing increasingly sophisticated investigative and therapeutic tools.
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Affiliation(s)
- Yaping Chen
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC, 3052, Australia
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility, 151 Wellington Road, Clayton, VIC, 3168, Australia
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Clayton, VIC, 3168, Australia
| | - Stella Aslanoglou
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC, 3052, Australia
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility, 151 Wellington Road, Clayton, VIC, 3168, Australia
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Clayton, VIC, 3168, Australia
| | - Gediminas Gervinskas
- Ramaciotti Centre for Cryo-Electron Microscopy, Monash University, 15 Innovation Walk, Clayton, VIC, 3800, Australia
| | - Hazem Abdelmaksoud
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility, 151 Wellington Road, Clayton, VIC, 3168, Australia
- Future Industries Institute, University of South Australia, Mawson Lakes, SA, 5095, Australia
| | - Nicolas H Voelcker
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC, 3052, Australia
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility, 151 Wellington Road, Clayton, VIC, 3168, Australia
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Clayton, VIC, 3168, Australia
- INM-Leibniz Institute for New Materials, Campus D2 2, Saarbrücken, 66123, Germany
| | - Roey Elnathan
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC, 3052, Australia
- Melbourne Centre for Nanofabrication, Victorian Node of the Australian National Fabrication Facility, 151 Wellington Road, Clayton, VIC, 3168, Australia
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Abstract
The integration of drugs into nanocarriers favorably altered their pharmacodynamics and pharmacokinetics compared to free drugs, and increased their therapeutic index. However, selective cellular internalization in diseased tissues rather than normal tissues still presents a formidable challenge. In this chapter I will cover solutions involving environment-responsive cell-penetrating peptides (CPPs). I will discuss properties of CPPs as universal cellular uptake enhancers, and the modifications imparted to CPP-modified nanocarriers to confine CPP activation to diseased tissues.
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7
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Pinyon JL, Klugmann M, Lovell NH, Housley GD. Dual-Plasmid Bionic Array-Directed Gene Electrotransfer in HEK293 Cells and Cochlear Mesenchymal Cells Probes Transgene Expression and Cell Fate. Hum Gene Ther 2019; 30:211-224. [DOI: 10.1089/hum.2018.062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Jeremy L. Pinyon
- Translational Neuroscience Facility and Department of Physiology, School of Medical Sciences, and UNSW Sydney, Sydney, Australia
| | - Matthias Klugmann
- Translational Neuroscience Facility and Department of Physiology, School of Medical Sciences, and UNSW Sydney, Sydney, Australia
| | - Nigel H. Lovell
- Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, Australia
| | - Gary D. Housley
- Translational Neuroscience Facility and Department of Physiology, School of Medical Sciences, and UNSW Sydney, Sydney, Australia
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8
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Abstract
Electrotransfection (ET) is a nonviral method for delivery of various types of molecules into cells both in vitro and in vivo. Close to 90 clinical trials that involve the use of ET have been performed, and approximately half of them are related to cancer treatment. Particularly, ET is an attractive technique for cancer immunogene therapy because treatment of cells with electric pulses alone can induce immune responses to solid tumors, and the responses can be further enhanced by ET of plasmid DNA (pDNA) encoding therapeutic genes. Compared to other gene delivery methods, ET has several unique advantages. It is relatively inexpensive, flexible, and safe in clinical applications, and introduces only naked pDNA into cells without the use of additional chemicals or viruses. However, the efficiency of ET is still low, partly because biological mechanisms of ET in cells remain elusive. In previous studies, it was believed that pDNA entered the cells through transient pores created by electric pulses. As a result, the technique is commonly referred to as electroporation. However, recent discoveries have suggested that endocytosis plays an important role in cellular uptake and intracellular transport of electrotransfected pDNA. This review will discuss current progresses in the study of biological mechanisms underlying ET and future directions of research in this area. Understanding the mechanisms of pDNA transport in cells is critical for the development of new strategies for improving the efficiency of gene delivery in tumors.
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Affiliation(s)
- Lisa D Cervia
- Department of Biomedical Engineering , Duke University , Durham , North Carolina 27708 , United States
| | - Fan Yuan
- Department of Biomedical Engineering , Duke University , Durham , North Carolina 27708 , United States
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9
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Ulkoski D, Scholz C. Impact of Cationic Charge Density and PEGylated Poly(Amino Acid) Tercopolymer Architecture on Their Use as Gene Delivery Vehicles. Part 2: DNA Protection, Stability, Cytotoxicity, and Transfection Efficiency. Macromol Biosci 2018; 18:e1800109. [DOI: 10.1002/mabi.201800109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 05/02/2018] [Indexed: 01/30/2023]
Affiliation(s)
- David Ulkoski
- Department of Chemistry; University of Alabama in Huntsville; Department of Chemistry; University of Alabama in Huntsville; 301 Sparkman Drive Huntsville AL 35899 USA
| | - Carmen Scholz
- Department of Chemistry; University of Alabama in Huntsville; Department of Chemistry; University of Alabama in Huntsville; 301 Sparkman Drive Huntsville AL 35899 USA
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10
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Suppressing mosaicism by Au nanowire injector-driven direct delivery of plasmids into mouse embryos. Biomaterials 2017; 138:169-178. [DOI: 10.1016/j.biomaterials.2017.05.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Revised: 05/16/2017] [Accepted: 05/26/2017] [Indexed: 12/12/2022]
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11
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Heller P, Zhou J, Weber B, Hobernik D, Bros M, Schmid F, Barz M. The Influence of Block Ionomer Microstructure on Polyplex Properties: Can Simulations Help to Understand Differences in Transfection Efficiency? SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2017; 13:1603694. [PMID: 28234427 DOI: 10.1002/smll.201603694] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 01/04/2017] [Indexed: 06/06/2023]
Abstract
Gene therapies enable therapeutic interventions at gene transcription and translation level, providing enormous potential to improve standards of care for multiple diseases. Nonviral transfection agents and in particular polyplexes based on block ionomers are-besides viral vectors and cationic lipid formulations-among the most promising systems for this purpose. Block ionomers combine a hydrophilic noncharged block, e.g., polyethylene glycol (PEG), with a hydrophilic cationic block. For efficient transfection, however, endosomolytic moieties, e.g., imidazoles, are additionally required to facilitate endosomal escape, which raises the general question how to distribute these functionalities within the block copolymer. Combining molecular dynamics simulation with physicochemical and biological characterization, this work aims to provide a first rational for the influence of block ionomer microstructure on polyplex properties, e.g., size, shape, and transfection efficiency. Our findings underline that a triblock microstructure is most efficient in compacting pDNA, which reduces polyplex size, enhances stability against degradation by DNase I, and thus provides better transfection performance.
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Affiliation(s)
- Philipp Heller
- Graduate School Materials Science in Mainz, Johannes Gutenberg University, Staudingerweg 9, 55128, Mainz, Germany
- Institute of Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55099, Mainz, Germany
| | - Jiajia Zhou
- School of Chemistry and Environment, Center of Soft Matter Physics and Its Applications, Beihang University, Xueyuan Road 37, Beijing, 100191, China
| | - Benjamin Weber
- Institute of Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55099, Mainz, Germany
| | - Dominika Hobernik
- Department of Dermatology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Matthias Bros
- Department of Dermatology, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, 55131, Mainz, Germany
| | - Friederike Schmid
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 9, 55099, Mainz, Germany
| | - Matthias Barz
- Institute of Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55099, Mainz, Germany
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12
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Vaidyanathan S, Chen J, Orr BG, Banaszak Holl MM. Cationic Polymer Intercalation into the Lipid Membrane Enables Intact Polyplex DNA Escape from Endosomes for Gene Delivery. Mol Pharm 2016; 13:1967-78. [PMID: 27111496 DOI: 10.1021/acs.molpharmaceut.6b00139] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Developing improved cationic polymer-DNA polyplexes for gene delivery requires improved understanding of DNA transport from endosomes into the nucleus. Using a FRET-capable oligonucleotide molecular beacon (OMB), we monitored the transport of intact DNA to cell organelles. We observed that for effective (jetPEI) and ineffective (G5 PAMAM) vectors, the fraction of cells displaying intact OMB in the cytosol (jetPEI ≫ G5 PAMAM) quantitatively predicted the fraction expressing transgene (jetPEI ≫ G5 PAMAM). Intact OMB delivered with PAMAM and confined to endosomes could be released to the cytosol by the subsequent addition of L-PEI, with a corresponding 10-fold increase in transgene expression. These results suggest that future vector development should optimize vectors for intercalation into, and destabilization of, the endosomal membrane. Finally, the study highlights a two-step strategy in which the pDNA is loaded in cells using one vector and endosomal release is mediated by a second agent.
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Affiliation(s)
- Sriram Vaidyanathan
- Departments of †Biomedical Engineering and ‡Chemistry and Programs in §Applied Physics and ⊥Macromolecular Science and Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Junjie Chen
- Departments of †Biomedical Engineering and ‡Chemistry and Programs in §Applied Physics and ⊥Macromolecular Science and Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Bradford G Orr
- Departments of †Biomedical Engineering and ‡Chemistry and Programs in §Applied Physics and ⊥Macromolecular Science and Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Mark M Banaszak Holl
- Departments of †Biomedical Engineering and ‡Chemistry and Programs in §Applied Physics and ⊥Macromolecular Science and Engineering, University of Michigan , Ann Arbor, Michigan 48109, United States
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