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Baron Y, Sens J, Lange L, Nassauer L, Klatt D, Hoffmann D, Kleppa MJ, Barbosa PV, Keisker M, Steinberg V, Suerth JD, Vondran FW, Meyer J, Morgan M, Schambach A, Galla M. Improved alpharetrovirus-based Gag.MS2 particles for efficient and transient delivery of CRISPR-Cas9 into target cells. MOLECULAR THERAPY. NUCLEIC ACIDS 2022; 27:810-823. [PMID: 35141043 PMCID: PMC8801357 DOI: 10.1016/j.omtn.2021.12.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 12/29/2021] [Indexed: 12/12/2022]
Abstract
DNA-modifying technologies, such as the CRISPR-Cas9 system, are promising tools in the field of gene and cell therapies. However, high and prolonged expression of DNA-modifying enzymes may cause cytotoxic and genotoxic side effects and is therefore unwanted in therapeutic approaches. Consequently, development of new and potent short-term delivery methods is of utmost importance. Recently, we developed non-integrating gammaretrovirus- and MS2 bacteriophage-based Gag.MS2 (g.Gag.MS2) particles for transient transfer of non-retroviral CRISPR-Cas9 RNA into target cells. In the present study, we further improved the technique by transferring the system to the alpharetroviral vector platform (a.Gag.MS2), which significantly increased CRISPR-Cas9 delivery into target cells and allowed efficient targeted knockout of endogenous TP53/Trp53 genes in primary murine fibroblasts as well as primary human fibroblasts, hepatocytes, and cord-blood-derived CD34+ stem and progenitor cells. Strikingly, co-packaging of Cas9 mRNA and multiple single guide RNAs (sgRNAs) into a.Gag.MS2 chimera displayed efficient targeted knockout of up to three genes. Co-transfection of single-stranded DNA donor oligonucleotides during CRISPR-Cas9 particle production generated all-in-one particles, which mediated up to 12.5% of homology-directed repair in primary cell cultures. In summary, optimized a.Gag.MS2 particles represent a versatile tool for short-term delivery of DNA-modifying enzymes into a variety of target cells, including primary murine and human cells.
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Affiliation(s)
- Yvonne Baron
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Johanna Sens
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Lucas Lange
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Larissa Nassauer
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Denise Klatt
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Dirk Hoffmann
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Marc-Jens Kleppa
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Philippe Vollmer Barbosa
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
- Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover 30625, Germany
| | - Maximilian Keisker
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Viviane Steinberg
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Julia D. Suerth
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Florian W.R. Vondran
- ReMediES, Department of General, Visceral and Transplant Surgery, Hannover Medical School, Hannover 30625, Germany
- German Centre for Infection Research (DZIF), partner site Hannover-Braunschweig, Hannover Medical School, Hannover 30625, Germany
| | - Johann Meyer
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Michael Morgan
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
| | - Axel Schambach
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Melanie Galla
- Institute of Experimental Hematology, Hannover Medical School, Hannover 30625, Germany
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Pinnapireddy SR, Giselbrecht J, Strehlow B, Janich C, Husteden C, Meister A, Loppnow H, Sedding D, Erdmann F, Hause G, Brezesinski G, Groth T, Langner A, Bakowsky U, Wölk C. A triple chain polycationic peptide-mimicking amphiphile - efficient DNA-transfer without co-lipids. Biomater Sci 2019; 8:232-249. [PMID: 31681923 DOI: 10.1039/c9bm01093a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Non-viral gene delivery in its current form is largely dependent upon the ability of a delivery vehicle to protect its cargo in the extracellular environment and release it efficiently inside the target cell. Also a simple delivery system is required to simplify a GMP conform production if a marketing authorization is striven for. This work addresses these problems. We have developed a synthetic polycationic peptide-mimicking amphiphile, namely DiTT4, which shows efficient transfection rates and good biocompatibility without the use of a co-lipid in the formulation. The lipid-nucleic acid complex (lipoplex) was characterized at the structural (electron microscopy), physical (laser Doppler velocimetry and atomic force microscopy) and molecular levels (X-ray scattering). Stability studies of the lipoplexes in the presence of serum and heparin indicated a stable formation capable of protecting the cargo against the extracellular milieu. Hemocompatibility studies (hemolysis, complement activation and erythrocyte aggregation) demonstrated the biocompatibility of the formulation for systemic administration. The transfection efficiency was assessed in vitro using the GFP assay and confocal laser scanning microscopy studies. With the chorioallantoic membrane model, an animal replacement model according to the 3R strategy (replacement, refinement, and reduction), initial in vivo experiments were performed which demonstrate fast and efficient transfection in complex tissues and excellent biocompatibility.
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Affiliation(s)
- Shashank Reddy Pinnapireddy
- Department of Pharmaceutics and Biopharmaceutics, University of Marburg, Robert-Koch-Str. 4, 35037, Marburg, Germany.
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3
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Molina-Pinilla I, Hakkou K, Romero-Azogil L, Benito E, García-Martín MG, Bueno-Martínez M. Synthesis of degradable linear cationic poly(amide triazole)s with DNA-condensation capability. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.01.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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4
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Quantitative monitoring of the cytoplasmic release of NCp7 proteins from individual HIV-1 viral cores during the early steps of infection. Sci Rep 2019; 9:945. [PMID: 30700731 PMCID: PMC6353972 DOI: 10.1038/s41598-018-37150-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 11/29/2018] [Indexed: 12/15/2022] Open
Abstract
Fluorescence microscopy imaging of individual HIV-1 viruses necessitates a specific labeling of viral structures that minimally perturbs the infection process. Herein, we used HIV-1 pseudoviruses containing NCp7 fused to a tetracystein (TC) tag, labeled by a biarsenical fluorescein derivative (FlAsH) to quantitatively monitor the NCp7 protein concentration in the viral cores during the early stages of infection. Single particle imaging of individual pseudoviruses with defined ratios of TC-tagged to non tagged NCp7 proteins, together with theoretical modeling of energy transfer between FlAsH dyes, showed that the high packaging of TC-tagged proteins in the viral cores causes a strong fluorescence quenching of FlAsH and that the fluorescence intensity of individual viral complexes is an appropriate parameter to monitor changes in the amount of NCp7 molecules within the viral particles during infection. Interestingly, we observed a dramatic fluorescence increase of individual FlAsH-labeled pseudoviruses containing 100% TC-tagged NCp7 proteins in infected cells at 8 and 16 h post-infection. This effect was significantly lower for pseudoviruses expressing TC-tagged integrase. Therefore, this fluorescence increase is likely related to the cytoplasmic viral transformation and the release of NCp7 molecules from the viral complexes. This loss of quenching effect is largely reduced when reverse transcriptase is inhibited, showing that NCp7 release is connected to viral DNA synthesis. A spatial analysis further revealed that NCp7-TC release is more pronounced in the perinuclear space, where capsid disassembly is thought to be completed. Quantification of NCp7-TC content based on fluorescence quenching presented in this study evidences for the first time the cytoplasmic release of NCp7 during the remodeling of HIV-1 viral particles on their journey toward the nucleus. The developed approach can be applied to quantify dye concentrations in a wide range of nano-objects by fluorescence microscopy techniques.
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5
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Biomaterial-guided delivery of gene vectors for targeted articular cartilage repair. Nat Rev Rheumatol 2018; 15:18-29. [DOI: 10.1038/s41584-018-0125-2] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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6
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Lysova I, Spiegelhalter C, Réal E, Zgheib S, Anton H, Mély Y. ReAsH/tetracystein-based correlative light-electron microscopy for HIV-1 imaging during the early stages of infection. Methods Appl Fluoresc 2018; 6:045001. [PMID: 29938685 DOI: 10.1088/2050-6120/aacec1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Visualization of viruses in the host cell during the course of infection by correlative light-electron microscopy (CLEM) requires a specific labelling of the viral structures in order to recognize the nanometric viral cores in the intracellular environment. For Human immunodeficiency virus type 1 (HIV-1), the labelling approaches developed for fluorescence microscopy are generally not suited for transmission electron microscopy (TEM), so that imaging of HIV-1 particles in infected cells by CLEM is not straightforward. Herein, we adapt the labeling approach with a tetracystein tag (TC) and a biarsenical resorufin-based label (ReAsH) for monitoring the HIV-1 particles during the early stages of HIV-1 infection by CLEM. In this approach, the ReAsH fluorophore triggers the photo-conversion of 3,3-diaminobenzidine tetrahydrochloride (DAB), generating a precipitate sensitive to osmium tetroxide staining that can be visualized by transmission electron microscopy. The TC tag is fused to the nucleocapsid protein NCp7, a nucleic acid chaperone that binds to the viral genome. HeLa cells, infected by ReAsH-labeled pseudoviruses containg NCp7-TC proteins exhibit strong fluorescent cytoplasmic spots that overlap with dark precipitates in the TEM sections. The DAB precipitates corresponding to single viral cores are observed all over the cytoplasm, and notably near microtubules and nuclear pores. This work describes for the first time a specific contrast given by HIV-1 viral proteins in TEM images and opens new perspectives for the use of CLEM to monitor the intracellular traffic of viral complexes.
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Affiliation(s)
- Iryna Lysova
- Laboratoire de Bioimagerie et Pathologies, CNRS UMR 7021, Strasbourg University, Faculty of Pharmacy, 74 route du Rhin, Illkirch, France
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Böker KO, Lemus-Diaz N, Rinaldi Ferreira R, Schiller L, Schneider S, Gruber J. The Impact of the CD9 Tetraspanin on Lentivirus Infectivity and Exosome Secretion. Mol Ther 2017; 26:634-647. [PMID: 29221804 DOI: 10.1016/j.ymthe.2017.11.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/24/2017] [Accepted: 11/11/2017] [Indexed: 12/18/2022] Open
Abstract
Efficient transduction tools are a hallmark for both research and therapy development. Here, we introduce new insights into the generation of lentiviral vectors with improved performance by utilizing producer cells with increased production rates of extracellular vesicles through CD9 overexpression. Most human cells secrete small vesicles from their surface (microvesicles) or intraluminal endosome-derived membranes (exosomes). In particular, enhanced levels of the tetraspanin CD9 result in significantly increased numbers of extracellular vesicles with exosome-like features that were secreted from four different human cell lines. Intriguingly, exosomes and their biogenesis route display similarities to lentivirus and we examined the impact of CD9 expression on release and infectivity of recombinant lentiviral vectors. Although the titers of released viral particles were not increased upon production in high CD9 cells, we observed improved performance in terms of both speed and efficiency of lentiviral gene delivery into numerous human cell lines, including HEK293, HeLa, SH-SY5Y, as well as B and T lymphocytes. Here, we demonstrate that enhanced CD9 enables lentiviral transduction in the absence of any pseudotyping viral glycoprotein or fusogenic molecule. Our findings indicate an important role of CD9 for lentiviral vector and exosome biogenesis and point out a remarkable function of this tetraspanin in membrane fusion, viral infectivity, and exosome-mediated horizontal information transfer.
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Affiliation(s)
- Kai O Böker
- Junior Research Group Medical RNA Biology, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, 37077 Göttingen, Germany; Department for Trauma Surgery, Orthopaedics and Plastic Surgery, University Medical Center, Robert-Koch-Straße 40, 37075 Göttingen, Germany
| | - Nicolas Lemus-Diaz
- Junior Research Group Medical RNA Biology, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, 37077 Göttingen, Germany
| | - Rafael Rinaldi Ferreira
- Junior Research Group Medical RNA Biology, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, 37077 Göttingen, Germany
| | - Lara Schiller
- Junior Research Group Medical RNA Biology, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, 37077 Göttingen, Germany
| | - Stefan Schneider
- Junior Research Group Medical RNA Biology, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, 37077 Göttingen, Germany
| | - Jens Gruber
- Junior Research Group Medical RNA Biology, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, 37077 Göttingen, Germany.
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8
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Palesch D, Boldt F, Müller JA, Eisele K, Stürzel CM, Wu Y, Münch J, Weil T. PEGylated Cationic Serum Albumin for Boosting Retroviral Gene Transfer. Chembiochem 2016; 17:1504-8. [PMID: 27239020 DOI: 10.1002/cbic.201600193] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Indexed: 01/28/2023]
Abstract
Retroviral vectors are common tools for introducing genes into the genome of a cell. However, low transduction rates are a major limitation in retroviral gene transfer, especially in clinical applications. We generated cationic human serum albumin (cHSA) protected by a shell of poly(ethylene glycol) (PEG); this significantly enhanced retroviral gene transduction with potentially attractive pharmacokinetics and low immunogenicity. By screening a panel of chemically optimized HSA compounds, we identified a very potent enhancer that boosted the transduction rates of viral vectors. Confocal microscopy revealed a drastically increased number of viral particles attached to the surfaces of target cells. In accordance with the positive net charge of cationic and PEGylated HSA, this suggests a mechanism of action in which the repulsion of the negatively charged cellular and viral vector membranes is neutralized, thereby promoting attachment and ultimately transduction. Importantly, the transduction-enhancing PEGylated HSA derivative evaded recognition by HSA-specific antibodies and macrophage activation. Our findings hold great promise for facilitating improved retroviral gene transfer.
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Affiliation(s)
- David Palesch
- Institute of Molecular Virology, Ulm University Medical Center, Meyerhofstrasse 1, 89081, Ulm, Germany
| | - Felix Boldt
- Institute of Organic Chemistry III/Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Janis A Müller
- Institute of Molecular Virology, Ulm University Medical Center, Meyerhofstrasse 1, 89081, Ulm, Germany
| | - Klaus Eisele
- Institute of Organic Chemistry III/Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Christina M Stürzel
- Institute of Molecular Virology, Ulm University Medical Center, Meyerhofstrasse 1, 89081, Ulm, Germany
| | - Yuzhou Wu
- Institute of Organic Chemistry III/Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Jan Münch
- Institute of Molecular Virology, Ulm University Medical Center, Meyerhofstrasse 1, 89081, Ulm, Germany.
| | - Tanja Weil
- Institute of Organic Chemistry III/Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
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9
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Bai R, Zhang XJ, Li YL, Liu JP, Zhang HB, Xiao WL, Pu JX, Sun HD, Zheng YT, Liu LX. SJP-L-5, a novel small-molecule compound, inhibits HIV-1 infection by blocking viral DNA nuclear entry. BMC Microbiol 2015; 15:274. [PMID: 26630969 PMCID: PMC4667461 DOI: 10.1186/s12866-015-0605-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 11/24/2015] [Indexed: 11/15/2022] Open
Abstract
Background Small-molecule compounds that inhibit human immunodeficiency virus type 1 (HIV-1) infection can be used not only as drug candidates, but also as reagents to dissect the life cycle of the virus. Thus, it is desirable to have an arsenal of such compounds that inhibit HIV-1 infection by various mechanisms. Until now, only a few small-molecule compounds that inhibit nuclear entry of viral DNA have been documented. Results We identified a novel, small-molecule compound, SJP-L-5, that inhibits HIV-1 infection. SJP-L-5 is a nitrogen-containing, biphenyl compound whose synthesis was based on the dibenzocyclooctadiene lignan gomisin M2, an anti-HIV bioactive compound isolated from Schisandra micrantha A. C. Smith. SJP-L-5 displayed relatively low cytotoxicity (50 % cytoxicity concentrations were greater than 200 μg/ml) and high antiviral activity against a variety of HIV strains (50 % effective concentrations (EC50)) of HIV-1 laboratory-adapted strains ranged from 0.16–0.97 μg/ml; EC50s of primary isolates ranged from 1.96–5.33 μg/ml). Analyses of the viral DNA synthesis indicated that SJP-L-5 specifically blocks the entry of the HIV-1 pre-integration complex (PIC) into the nucleus. Further results implicated that SJP-L-5 inhibits the disassembly of HIV-1 particulate capsid in the cytoplasm of the infected cells. Conclusions SJP-L-5 is a novel small-molecule compound that inhibits HIV-1 nuclear entry by blocking the disassembly of the viral core. Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0605-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ru Bai
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
| | - Xing-Jie Zhang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and the Kunming Institute of Zoology of the Chinese Academy of Sciences, Kunming, 650223, P. R. China.
| | - Yan-Li Li
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
| | - Jing-Ping Liu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Hong-Bin Zhang
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China.
| | - Wei-Lie Xiao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Jian-Xin Pu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Han-Dong Sun
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Yong-Tang Zheng
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and the Kunming Institute of Zoology of the Chinese Academy of Sciences, Kunming, 650223, P. R. China.
| | - Li-Xin Liu
- Sun Yat-Sen University, Guangzhou, 510275, P. R. China.
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Keswani RK, Lazebnik M, Pack DW. Intracellular trafficking of hybrid gene delivery vectors. J Control Release 2015; 207:120-30. [PMID: 25883029 DOI: 10.1016/j.jconrel.2015.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 04/10/2015] [Accepted: 04/11/2015] [Indexed: 10/23/2022]
Abstract
Viral and non-viral gene delivery vectors are in development for human gene therapy, but both exhibit disadvantages such as inadequate efficiency, lack of cell-specific targeting or safety concerns. We have recently reported the design of hybrid delivery vectors combining retrovirus-like particles with synthetic polymers or lipids that are efficient, provide sustained gene expression and are more stable compared to native retroviruses. To guide further development of this promising class of gene delivery vectors, we have investigated their mechanisms of intracellular trafficking. Moloney murine leukemia virus-like particles (M-VLPs) were complexed with chitosan (Chi) or liposomes (Lip) comprising DOTAP, DOPE and cholesterol to form the hybrid vectors (Chi/M-VLPs and Lip/M-VLPs, respectively). Transfection efficiency and cellular internalization of the vectors were quantified in the presence of a panel of inhibitors of various endocytic pathways. Intracellular transport and trafficking kinetics of the hybrid vectors were dependent on the synthetic component and used a combination of clathrin- and caveolar-dependent endocytosis and macropinocytosis. Chi/M-VLPs were slower to transfect compared to Lip/M-VLPs due to the delayed detachment of the synthetic component. The synthetic component of hybrid gene delivery vectors plays a significant role in their cellular interactions and processing and is a key parameter for the design of more efficient gene delivery vehicles.
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Affiliation(s)
- Rahul K Keswani
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801, USA
| | - Mihael Lazebnik
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801, USA
| | - Daniel W Pack
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY 40506, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40506, USA.
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11
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Improved intracellular delivery of peptide- and lipid-nanoplexes by natural glycosides. J Control Release 2015; 206:75-90. [PMID: 25758332 DOI: 10.1016/j.jconrel.2015.03.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 03/05/2015] [Accepted: 03/06/2015] [Indexed: 12/29/2022]
Abstract
Targeted nanocarriers undergo endocytosis upon binding to their membrane receptors and are transported into cellular compartments such as late endosomes and lysosomes. In gene delivery the genetic material has to escape from the cellular compartments into the cytosol. The process of endosomal escape is one of the most critical steps for successful gene delivery. For this reason synthetic lipids with fusogenic properties such as 2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) are integrated into the nanocarriers. In this study we show that a natural, plant derived glycoside (SO1861) from Saponaria officinalis L. greatly improves the efficacy of lipid based as well as non-lipid based targeted nanoplexes consisting of a targeted K16 peptide with a nucleic acid binding domain and plasmid-DNA, minicircle-DNA or small interfering RNA (siRNA). By confocal live cell imaging and single cell analyses, we demonstrate that SO1861 augments the escape of the genetic cargo out of the intracellular compartments into the cytosol. Co-localisation experiments with fluorescence labelled dextran and transferrin indicate that SO1861 induces the release of the genetic cargo out of endosomes and lysosomes. However, the transduction efficacy of a lentivirus based gene delivery system was not augmented. In order to design receptor-targeted nanoplexes (LPD) with improved functional properties, SO1861 was integrated into the lipid matrix of the LPD. The SO1861 sensitized LPD (LPDS) were characterized by dynamic light scattering and transmission electron microscopy. Compared to their LPD counterparts the LPDS-nanoplexes showed a greatly improved gene delivery. As shown by differential scanning calorimetry SO1861 can be easily integrated into the lipid bilayer of glycerophospholipid model membranes. This underlines the great potential of SO1861 as a new transfection multiplier for non-viral gene delivery systems.
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12
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Keswani R, Su K, Pack DW. Efficient in vitro gene delivery by hybrid biopolymer/virus nanobiovectors. J Control Release 2014; 192:40-6. [PMID: 25009978 DOI: 10.1016/j.jconrel.2014.06.060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 04/03/2014] [Accepted: 06/30/2014] [Indexed: 10/25/2022]
Abstract
Recombinant retroviruses provide highly efficient gene delivery and the potential for sustained gene expression, but suffer from significant disadvantages including low titer, expensive production, poor stability and limited flexibility for modification of tropism. In contrast, polymer-based vectors are more robust and allow cell- and tissue-specific deliveries via conjugation of ligands, but are comparatively inefficient. The design of hybrid gene delivery agents comprising both virally derived and synthetic materials (nanobiovectors) represents a promising approach to development of safe and efficient gene therapy vectors. Non-infectious murine leukemia virus-like particles (M-VLPs) were electrostatically complexed with chitosan (χ) to replace the function of the viral envelope protein. At optimal fabrication conditions and compositions, ranging from 6 to 9μg chitosan/10(9) M-VLPs at 10×10(9)M-VLPs/ml to 40μg chitosan/10(9) M-VLPs at 2.5×10(9)M-VLPs/ml, χ/M-VLPs were ~300-350nm in diameter and exhibited efficient transfection similar to amphotropic MLV vectors. In addition, these nanobiovectors were non-cytotoxic and provided sustained transgene expression for at least three weeks in vitro. This combination of biocompatible synthetic agents with inactive viral particles to form a highly efficient hybrid vector is a significant extension in the development of novel gene delivery platforms.
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Affiliation(s)
- Rahul Keswani
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801, USA
| | - Kai Su
- Department of Chemical and Materials, University of Kentucky, Lexington, KY 40506-0046, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536-0596, USA
| | - Daniel W Pack
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801, USA; Department of Chemical and Materials, University of Kentucky, Lexington, KY 40506-0046, USA; Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536-0596, USA.
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Abstract
To improve the nuclear-targeted delivery of non-viral vectors, extensive effort has been carried out on the development of smart vectors which could overcome multiple barriers. The nuclear envelope presents a major barrier to transgene delivery. Viruses are capable of crossing the nuclear envelope to efficiently deliver their genome into the nucleus through the specialized protein components. However, non-viral vectors are preferred over viral ones because of the safety concerns associated with the latter. Non-viral delivery systems have been designed to include various types of components to enable nuclear translocation at the periphery of the nucleus. This review summarizes the progress of research regarding nuclear transport mechanisms. "Smart" non-viral vectors that have been modified by peptides and other small molecules are able to facilitate the nuclear translocation and enhance the efficacy of gene expression. The resulting technology may also enhance delivery of other macromolecules to the nucleus.
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Affiliation(s)
- Jing Yao
- Division of Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill , Chapel Hill, NC , USA and
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Liu Y, Tai A, Joo KI, Wang P. Visualization of DC-SIGN-mediated entry pathway of engineered lentiviral vectors in target cells. PLoS One 2013; 8:e67400. [PMID: 23840690 PMCID: PMC3696072 DOI: 10.1371/journal.pone.0067400] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/17/2013] [Indexed: 01/08/2023] Open
Abstract
Dendritic cells (DCs) are potent antigen-presenting cells and therefore have enormous potential as vaccine targets. We have previously developed an engineered lentiviral vector (LV) that is pseudotyped with a mutated Sindbis virus glycoprotein (SVGmu), which is capable of targeting DCs through Dendritic Cell-specific ICAM3-grabbing Nonintegrin (DC-SIGN), a receptor that is predominantly expressed by DCs. In this study, we aimed to elucidate the internalization and trafficking mechanisms of this viral vector system through direct visualization of GFP-Vpr-tagged viral particles in target DCs, which was further corroborated by drug inhibition and dominant-negative mutants of cellular proteins that regulate the endocytic traffic. We demonstrated that our engineered LVs enter the cell via receptor-mediated clathrin- and dynamin-dependent endocytosis. Microtubule networks were also involved in a productive infection. Viral vector fusion was low-pH-dependent and occurred in the early endosomal stage of the intracellular transport. Autophagy was also examined for its effect on transduction efficiency, and we observed that enhanced autophage activity reduced vector infectivity, while suppressed autophagy boosted transduction efficiency. This study shed some light on the internalization and trafficking mechanisms of DC-directed LVs and offers some strategies to further improve the efficiency of LV-mediated gene therapy.
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Affiliation(s)
- Yarong Liu
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California, United States of America
| | - April Tai
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California, United States of America
| | - Kye-Il Joo
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California, United States of America
- * E-mail: or (KJ); or (PW)
| | - Pin Wang
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California, United States of America
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, United States of America
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, California, United States of America
- * E-mail: or (KJ); or (PW)
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15
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JENKINS STUARTI, PICKARD MARKR, CHARI DIVYAM. MAGNETIC NANOPARTICLE MEDIATED GENE DELIVERY IN OLIGODENDROGLIAL CELLS: A COMPARISON OF DIFFERENTIATED CELLS VERSUS PRECURSOR FORMS. ACTA ACUST UNITED AC 2013. [DOI: 10.1142/s1793984412430015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Magnetic nanoparticles (MNPs) have emerged as a major platform for the formulation of magnetic vectors for nonviral gene delivery. Notably the application of "magnetofection" strategies (use of magnetic fields to increase MNP–cell interactions) can significantly enhance MNP mediated gene transfer. Despite the potential of this approach, the use of MNPs and magnetofection for gene delivery to oligodendrocytes (the cells that make and maintain myelin, the insulating sheath around nerve fibers in the central nervous system) has never been tested. Here, we prove the feasibility of using MNPs in conjunction with applied static or oscillating gradient magnetic fields (the "magnetofection" method) to deliver genes to oligodendrocytes; all applied magnetic field conditions resulted in greater transfection than the no field condition but overall transfection levels obtained were typically low (ca. < 6%). Oligodendrocyte transfection levels under all magnetic field conditions were less than a third compared with their parent cell population, the oligodendrocyte precursor cells. Our results demonstrate for the first time that, within cells of a specific neural lineage, the amenability to transfection is dependent on the differentiation status of the cell.
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Affiliation(s)
- STUART I. JENKINS
- Cellular and Neural Engineering Group, Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
| | - MARK R. PICKARD
- Cellular and Neural Engineering Group, Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
| | - DIVYA M CHARI
- Cellular and Neural Engineering Group, Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
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16
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Rodriguez-Garcia M, Biswas N, Patel MV, Barr FD, Crist SG, Ochsenbauer C, Fahey JV, Wira CR. Estradiol reduces susceptibility of CD4+ T cells and macrophages to HIV-infection. PLoS One 2013; 8:e62069. [PMID: 23614015 PMCID: PMC3629151 DOI: 10.1371/journal.pone.0062069] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 03/18/2013] [Indexed: 12/21/2022] Open
Abstract
The magnitude of the HIV epidemic in women requires urgent efforts to find effective preventive methods. Even though sex hormones have been described to influence HIV infection in epidemiological studies and regulate different immune responses that may affect HIV infection, the direct role that female sex hormones play in altering the susceptibility of target cells to HIV-infection is largely unknown. Here we evaluated the direct effect of 17-β-estradiol (E2) and ethinyl estradiol (EE) in HIV-infection of CD4+ T-cells and macrophages. Purified CD4+ T-cells and monocyte-derived macrophages were generated in vitro from peripheral blood and infected with R5 and X4 viruses. Treatment of CD4+ T-cells and macrophages with E2 prior to viral challenge reduced their susceptibility to HIV infection in a dose-dependent manner. Addition of E2 2 h after viral challenge however did not result in reduced infection. In contrast, EE reduced infection in macrophages to a lesser extent than E2 and had no effect on CD4+ T-cell infection. Reduction of HIV-infection induced by E2 in CD4+ T-cells was not due to CCR5 down-regulation, but was an entry-mediated mechanism since infection with VSV-G pseudotyped HIV was not modified by E2. In macrophages, despite the lack of an effect of E2 on CCR5 expression, E2–treatment reduced viral entry 2 h after challenge and increased MIP-1β secretion. These results demonstrate the direct effect of E2 on susceptibility of HIV-target cells to infection and indicate that inhibition of target cell infection involves cell-entry related mechanisms.
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Affiliation(s)
- Marta Rodriguez-Garcia
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, United States of America.
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17
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Characteristics of the cellular receptor influence the intracellular fate and efficiency of virus infection. J Virol 2013; 87:5916-25. [PMID: 23514894 DOI: 10.1128/jvi.00398-13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The intracellular fate of internalized virus-receptor complexes is suspected of influencing the efficiency of virus infection. However, direct evidence of a link between infection and the fate of internalized virus has been difficult to obtain. To directly address this question, we generated human 293 cell lines stably expressing comparable cell surface levels of three different members of the somatostatin receptor family (SSTR) which have natural differences in intracellular trafficking. Utilizing a glycoprotein that recognizes SSTR, we found that distinctive receptor subtype-specific destinations correlated with observable differences in the level of infection. Infection via SSTR-2 and -3 is restricted at a point after receptor binding and endocytosis but prior to penetration into the host cytoplasm. In contrast, entry via SSTR-5 featured a slower internalization with greater dependence on cholesterol. Quantitative real-time PCR showed that virus bound to SSTR-5 was directed to an intracellular environment that allowed near-wild-type (WT) levels of penetration, possibly due to a more favorable complement of host cell proteases, whereas SSTR-2 and -3 directed virions to a degradative compartment in which cytosol penetration was less efficient. Taken together, the results support that the superior receptor capacity of SSTR-5 results from its internalization into a cellular compartment that is more favorable to the cytoplasmic penetration of viral cores and reverse transcription. They suggest that the intracellular destination of internalized complexes is an important characteristic of a virus receptor and may have exerted a selective pressure on the choice of an entry receptor during evolution of viral glycoproteins.
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18
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Unciti-Broceta A, Díaz-Mochón JJ, Sánchez-Martín RM, Bradley M. The use of solid supports to generate nucleic acid carriers. Acc Chem Res 2012; 45:1140-52. [PMID: 22390230 DOI: 10.1021/ar200263c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Nucleic acids are the foundation stone of all cellular processes. Consequently, the use of DNA or RNA to treat genetic and acquired disorders (so called gene therapy) offers enormous potential benefits. The restitution of defective genes or the suppression of malignant genes could target a range of diseases, including cancers, inherited diseases (cystic fibrosis, muscular dystrophy, etc.), and viral infections. However, this strategy has a major barrier: the size and charge of nucleic acids largely restricts their transit into eukaryotic cells. Potential strategies to solve this problem include the use of a variety of natural and synthetic nucleic acid carriers. Driven by the aim and ambition of translating this promising therapeutic approach into the clinic, researchers have been actively developing advanced delivery systems for nucleic acids for more than 20 years. A decade ago we began our investigations of solid-phase techniques to construct families of novel nucleic acid carriers for transfection. We envisaged that the solid-phase synthesis of polycationic dendrimers and derivatized polyamimes would offer distinct advantages over solution phase techniques. Notably in solid phase synthesis we could take advantage of mass action and streamlined purification procedures, while simplifying the handling of compounds with high polarities and plurality of functional groups. Parallel synthesis methods would also allow rapid access to libraries of compounds with improved purities and yields over comparable solution methodologies and facilitate the development of structure activity relationships. We also twisted the concept of the solid-phase support on its head: we devised miniaturized solid supports that provided an innovative cell delivery vehicle in their own right, carrying covalently conjugated cargos (biomolecules) into cells. In this Account, we summarize the main outcomes of this series of chemically related projects.
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Affiliation(s)
- Asier Unciti-Broceta
- Edinburgh Cancer Research Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road South, Edinburgh EH4 2XR, United Kingdom
- Deliverics Ltd, Joseph Black Building, West Mains Road, Edinburgh EH9 3JJ, United Kingdom
| | - Juan José Díaz-Mochón
- Facultad de Farmacia, Universidad de Granada, Campus de la Cartuja s/n, 18071 Granada, Spain
| | | | - Mark Bradley
- School of Chemistry, University of Edinburgh, West Mains Road, EH9 3JJ Edinburgh, United Kingdom
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19
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Symens N, Soenen SJ, Rejman J, Braeckmans K, De Smedt SC, Remaut K. Intracellular partitioning of cell organelles and extraneous nanoparticles during mitosis. Adv Drug Deliv Rev 2012; 64:78-94. [PMID: 22210278 DOI: 10.1016/j.addr.2011.11.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 11/21/2011] [Accepted: 11/23/2011] [Indexed: 02/06/2023]
Abstract
The nucleocytoplasmic partitioning of nanoparticles as a result of cell division is highly relevant to the field of nonviral gene delivery. We reviewed the literature on the intracellular distribution of cell organelles (the endosomal vesicles, Golgi apparatus, endoplasmic reticulum and nucleus), foreign macromolecules (dextrans and plasmid DNA) and inorganic nanoparticles (gold, quantum dot and iron oxide) during mitosis. For nonviral gene delivery particles (lipid- or polymer-based), indirect proof of nuclear entry during mitosis is provided. We also describe how retroviruses and latent DNA viruses take advantage of mitosis to transfer their viral genome and segregate their episomes into the host daughter nuclei. Based on this knowledge, we propose strategies to improve nonviral gene delivery in dividing cells with the ultimate goal of designing nonviral gene delivery systems that are as efficient as their viral counterparts but non-immunogenic, non-oncogenic and easy and inexpensive to prepare.
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Affiliation(s)
- Nathalie Symens
- Laboratory of General Biochemistry and Physical Pharmacy, Ghent Research Group on Nanomedicines, Ghent University, Ghent, Belgium.
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20
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Focal Adhesion Proteins Talin-1 and Vinculin Negatively Affect Paxillin Phosphorylation and Limit Retroviral Infection. J Mol Biol 2011; 410:761-77. [DOI: 10.1016/j.jmb.2011.03.076] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 03/30/2011] [Accepted: 03/31/2011] [Indexed: 11/19/2022]
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21
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Joo KI, Fang Y, Liu Y, Xiao L, Gu Z, Tai A, Lee CL, Tang Y, Wang P. Enhanced real-time monitoring of adeno-associated virus trafficking by virus-quantum dot conjugates. ACS NANO 2011; 5:3523-35. [PMID: 21473596 PMCID: PMC3132586 DOI: 10.1021/nn102651p] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The unique spectral properties of semiconductor quantum dots (QDs) enable long-term live-cell imaging and ultrasensitive detection of viral particles, which in turn can potentially provide a practical means for detailed analysis of the underlying molecular mechanisms of virus entry. In this study, we report a general method of labeling adeno-associated virus serotype 2 (AAV2) with QDs for enhanced visualization of the intracellular behavior of viruses in living target cells. It was found that the mild conditions required for this QD conjugation reaction allowed for the retention of viral infectivity of AAV2. Furthermore, quantitative analysis of viral motility in living cells suggested that QD-labeling had no significant effect on the intracellular transport properties of AAV2 particles compared to those of conventional organic dye-labeled AAV2. Our imaging study demonstrated that QD-AAV2 was internalized mainly through a clathrin-dependent pathway and then trafficked through various endosomes. It was also observed that QD-AAV2 particles exploit the cytoskeleton network to facilitate their transport within cells, and the labeling study provided evidence that the ubiquitin-proteasome system was likely involved in the intracellular trafficking of AAV2, at least at the level of nuclear transport. Taken together, our findings reveal the potential of this QD-labeling method for monitoring the intracellular dynamics of virus-host cell interactions and interrogating the molecular mechanisms of viral infection in greater detail.
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Affiliation(s)
- Kye-Il Joo
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089
| | - Yun Fang
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089
| | - Yarong Liu
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089
| | - Liang Xiao
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089
| | - Zhen Gu
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095
| | - April Tai
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089
| | - Chi-Lin Lee
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089
| | - Yi Tang
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095
| | - Pin Wang
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089
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22
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Attenuated Salmonella typhimurium carrying shRNA-expressing vectors elicit RNA interference in murine bladder tumors. Acta Pharmacol Sin 2011; 32:368-74. [PMID: 21372828 DOI: 10.1038/aps.2010.224] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
AIM To examine whether attenuated Salmonella typhimurium (S typhimurium) could be used as an anti-cancer agent or a tumor-targeting vehicle for delivering shRNA-expressing pDNA into cancer cells in a mouse tumor model. METHODS Mouse bladder transitional cancer cell line (BTT-T739) expressing GFP was used, in which the GFP expression level served as an indicator of RNA interference (RNAi). BTT-T739-GFP tumor-bearing mice (4-6 weeks) were treated with S typhimurium carrying plasmids encoding shRNA against gfp or scrambled shRNA. The mRNA and protein expression levels of GFP were assessed 5 d after the bacteria administration, and the antitumor effects of S typhimurium were evaluated. RESULTS In BTT-T739-GFP tumor-bearing mice, S typhimurium (1×10(9) cfu, po) preferentially accumulated within tumors for as long as 40 d, and formed a tumor-to-normal tissue ratio that exceeded 1000/1. S typhimurium carrying plasmids encoding shRNA against gfp inhibited the expression of GFP in tumor cells by 73.4%. Orally delivered S typhimurium significantly delayed tumor growth and prolonged the survival of tumor-bearing mice. CONCLUSION This study demonstrates that attenuated S typhimurium can be used for both delivering shRNA-expressing vectors into tumor cells and eliciting RNAi, thus exerting anti-tumor activity, which may represent a new strategy for the treatment of solid tumors.
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23
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Thys W, De Houwer S, Demeulemeester J, Taltynov O, Vancraenenbroeck R, Gérard M, De Rijck J, Gijsbers R, Christ F, Debyser Z. Interplay between HIV entry and transportin-SR2 dependency. Retrovirology 2011; 8:7. [PMID: 21276267 PMCID: PMC3041740 DOI: 10.1186/1742-4690-8-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 01/30/2011] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Transportin-SR2 (TRN-SR2, TNPO3, transportin 3) was previously identified as an interaction partner of human immunodeficiency virus type 1 (HIV-1) integrase and functions as a nuclear import factor of HIV-1. A possible role of capsid in transportin-SR2-mediated nuclear import was recently suggested by the findings that a chimeric HIV virus, carrying the murine leukemia virus (MLV) capsid and matrix proteins, displayed a transportin-SR2 independent phenotype, and that the HIV-1 N74D capsid mutant proved insensitive to transportin-SR2 knockdown. RESULTS Our present analysis of viral specificity reveals that TRN-SR2 is not used to the same extent by all lentiviruses. The DNA flap does not determine the TRN-SR2 requirement of HIV-1. We corroborate the TRN-SR2 independent phenotype of the chimeric HIV virus carrying the MLV capsid and matrix proteins. We reanalyzed the HIV-1 N74D capsid mutant in cells transiently or stably depleted of transportin-SR2 and confirm that the N74D capsid mutant is independent of TRN-SR2 when pseudotyped with the vesicular stomatitis virus glycoprotein (VSV-G). Remarkably, although somewhat less dependent on TRN-SR2 than wild type virus, the N74D capsid mutant carrying the wild type HIV-1 envelope required TRN-SR2 for efficient replication. By pseudotyping with envelopes that mediate pH-independent viral uptake including HIV-1, measles virus and amphotropic MLV envelopes, we demonstrate that HIV-1 N74D capsid mutant viruses retain partial dependency on TRN-SR2. However, this dependency on TRN-SR2 is lost when the HIV N74D capsid mutant is pseudotyped with envelopes mediating pH-dependent endocytosis, such as the VSV-G and Ebola virus envelopes. CONCLUSION Here we discover a link between the viral entry of HIV and its interaction with TRN-SR2. Our data confirm the importance of TRN-SR2 in HIV-1 replication and argue for careful interpretation of experiments performed with VSV-G pseudotyped viruses in studies on early steps of HIV replication including the role of capsid therein.
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Affiliation(s)
- Wannes Thys
- Laboratory of Molecular Virology and Gene Therapy, Katholieke Universiteit Leuven, Kapucijnenvoer 33, VCTB+5, B-3000 Leuven, Flanders, Belgium
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24
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Jamali T, Jamali Y, Mehrbod M, Mofrad MRK. Nuclear pore complex: biochemistry and biophysics of nucleocytoplasmic transport in health and disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 287:233-86. [PMID: 21414590 DOI: 10.1016/b978-0-12-386043-9.00006-2] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Nuclear pore complexes (NPCs) are the gateways connecting the nucleoplasm and cytoplasm. This structures are composed of over 30 different proteins and 60-125 MDa of mass depending on type of species. NPCs are bilateral pathways that selectively control the passage of macromolecules into and out of the nucleus. Molecules smaller than 40 kDa diffuse through the NPC passively while larger molecules require facilitated transport provided by their attachment to karyopherins. Kinetic studies have shown that approximately 1000 translocations occur per second per NPC. Maintaining its high selectivity while allowing for rapid translocation makes the NPC an efficient chemical nanomachine. In this review, we approach the NPC function via a structural viewpoint. Putting together different pieces of this puzzle, this chapter confers an overall insight into what molecular processes are engaged in import/export of active cargos across the NPC and how different transporters regulate nucleocytoplasmic transport. In the end, the correlation of several diseases and disorders with the NPC structural defects and dysfunctions is discussed.
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Affiliation(s)
- T Jamali
- Department of Bioengineering, University of California, Berkeley, California, USA
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25
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Abstract
For many viruses, the ability to infect eukaryotic cells depends on their transport through the cytoplasm and across the nuclear membrane of the host cell. During this journey, viral contents are biochemically processed into complexes capable of both nuclear penetration and genomic integration. We develop a stochastic model of viral entry that incorporates all relevant aspects of transport, including convection along microtubules, biochemical conversion, degradation, and nuclear entry. Analysis of the nuclear infection probabilities in terms of the transport velocity, degradation, and biochemical conversion rates shows how certain values of key parameters can maximize the nuclear entry probability of the viral material. The existence of such "optimal" infection scenarios depends on the details of the biochemical conversion process and implies potentially counterintuitive effects in viral infection, suggesting new avenues for antiviral treatment. Such optimal parameter values provide a plausible transport-based explanation of the action of restriction factors and of experimentally observed optimal capsid stability. Finally, we propose a new interpretation of how genetic mutations unrelated to the mechanism of drug action may nonetheless confer novel types of overall drug resistance.
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Affiliation(s)
- Maria R. D'Orsogna
- Department of Mathematics, California State University Northridge, Los Angeles, California, United States of America
| | - Tom Chou
- Department of Biomathematics and Department of Mathematics, University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
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26
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Kasuya T, Kuroda S. Nanoparticles for human liver-specific drug and gene delivery systems: in vitro and in vivo advances. Expert Opin Drug Deliv 2009; 6:39-52. [PMID: 19236207 DOI: 10.1517/17425240802622096] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A wide variety of nanoparticles (NPs) that can deliver incorporated therapeutic materials such as compounds, proteins, genes and siRNAs to the human liver have been developed to treat liver-related diseases. This review describes NP-based drug and gene delivery systems such as liposomes (including lipoplex), polymer micelles, polymers (including polyplex) and viral vectors. It focuses upon the modification of these NPs to enhance liver specificity or delivery efficiency in vitro and in vivo. We discuss recent advances in drug and gene delivery systems specific to the human liver utilizing bio-nanocapsules comprising hepatitis B virus (HBV) envelope L protein, which has a pivotal role in HBV infection. These NP-based medicines may offer novel strategies for the treatment of liver-related diseases and contribute to the development of nanomedicines targeting other tissues.
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Affiliation(s)
- Takeshi Kasuya
- Osaka University, Institute of Scientific and Industrial Research, Department of Structural Molecular Biology, Ibaraki, Japan
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27
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Mudhakir D, Harashima H. Learning from the viral journey: how to enter cells and how to overcome intracellular barriers to reach the nucleus. AAPS JOURNAL 2009; 11:65-77. [PMID: 19194803 DOI: 10.1208/s12248-009-9080-9] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Accepted: 12/24/2008] [Indexed: 02/06/2023]
Abstract
Viruses deliver their genome into host cells where they subsequently replicate and multiply. A variety of relevant strategies have evolved by which viruses gain intracellular access and utilize cellular machinery for the synthesis of their genome. Therefore, the viral journey provides insight into the cell's trafficking machinery and how it can be best exploited to improve nonviral gene delivery systems. This review summarizes viral internalization pathways and intracellular trafficking of viruses, with an emphasis on the endosomal escape processes of nonenveloped viruses. Intracellular events from viral entry through nuclear delivery of the viral complementary DNA are also discussed.
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Affiliation(s)
- Diky Mudhakir
- Laboratory for Molecular Design of Pharmaceutics, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo, 060-0812, Japan
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28
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Joo KI, Wang P. Visualization of targeted transduction by engineered lentiviral vectors. Gene Ther 2008; 15:1384-96. [PMID: 18480844 PMCID: PMC2575058 DOI: 10.1038/gt.2008.87] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 04/01/2008] [Accepted: 04/01/2008] [Indexed: 12/23/2022]
Abstract
We have reported a method to target lentiviral vectors to specific cell types. This method requires the incorporation of two distinct molecules on the viral vector surface: one is an antibody that renders the targeting specificity for the engineered vector, and the other is a fusogenic protein that allows the engineered vector to enter the target cell. However, the molecular mechanism that controls the targeted infection needs to be defined. In this report, we tracked the individual lentiviral particles by labeling the virus with the GFP-Vpr fusion protein. We were able to visualize the surface-displayed proteins on a single virion as well as antibody-directed targeting to a desired cell type. We also demonstrated the dynamics of virus fusion with endosomes and monitored endosome-associated transport of viruses in target cells. Our results suggest that the fusion between the engineered lentivirus and endosomes takes place at the early endosome level, and that the release of the viral core into the cytosol at the completion of the virus-endosome fusion is correlated with the endosome maturation process. This imaging study sheds some light on the infection mechanism of the engineered lentivirus and can be beneficial to the design of more efficient gene delivery vectors.
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Affiliation(s)
- K-I Joo
- Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA
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29
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Naghavi MH, Goff SP. Retroviral proteins that interact with the host cell cytoskeleton. Curr Opin Immunol 2007; 19:402-7. [PMID: 17707624 PMCID: PMC2040053 DOI: 10.1016/j.coi.2007.07.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 06/22/2007] [Accepted: 07/04/2007] [Indexed: 11/26/2022]
Abstract
In the past decade, several lines of evidence have highlighted the importance of the host cell cytoskeleton in various stages of retroviral infection. To complete their lifecycle, retroviruses must penetrate the outer barrier of the cell membrane, and viral cores containing the viral genome must traverse the cytoplasm to the nucleus and then viral gene products must make the journey back to the cell surface in order to release new progeny. The presence of a dense cytoskeletal network and organelles in the cytoplasm creates an environment that greatly impedes diffusion of macromolecules such as viruses. As such, retroviruses have evolved means to hijack actin as well as microtubule cytoskeletal networks that regulate macromolecular movement within the host cell. Developing studies are discovering several host and viral factors that play important roles in retroviral trafficking.
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Affiliation(s)
- Mojgan H. Naghavi
- School of Medicine and Medical Science, Center for Research in Infectious Diseases, University College Dublin, Belfield, Dublin 4, Ireland
| | - Stephen P. Goff
- Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University, College of Physicians and Surgeons, New York, NY 10032
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30
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Abstract
Our aim is to characterize the poorly understood mechanisms that influence episomal transgene expression within the nucleus. We found that plasmid DNA micro-injected directly into a nucleus moves into a speckled pattern and occupies less nuclear volume than bovine serum albumin (BSA) or other inert molecules after 4 hours. In addition, plasmids that contain eukaryotic regulatory sequences and actively transcribe transgenes condense into a few select areas of the nucleoplasm and occupy less nuclear volume than bacterial vectors. This suggests that episomal DNA moves in a sequence and transcription-dependent manner. We have also found that plasmids traffic to specific subnuclear domains depending on their sequence. Our experiments show that plasmids with polymerase II regulatory elements will target to nuclear spliceosome regions, while plasmids with the polymerase I promoter often traffic into nucleoli. Further elucidation of intranuclear plasmid trafficking behavior may lead to a better understanding of gene expression, and thereby help to improve basic laboratory techniques and clinical gene therapies.
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Affiliation(s)
| | - David A. Dean
- Address all correspondence to. David A. Dean, Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, 240 E. Huron Ave, McGaw 2336, Chicago, IL 60611, Tel: 312-503-3121, Fax: 312-908-4650,
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Recillas-Targa F. Multiple strategies for gene transfer, expression, knockdown, and chromatin influence in mammalian cell lines and transgenic animals. Mol Biotechnol 2007; 34:337-54. [PMID: 17284781 DOI: 10.1385/mb:34:3:337] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 12/31/2022]
Abstract
Manipulation of the eukaryotic genome has contributed to the progress in our knowledge of multicellular organisms but has also ameliorated our experimental strategies. Biological questions can now be addressed with more efficiency and reproducibility. There are new and varied strategies for gene transfer and sequence manipulation with improved methodologies that facilitate the acquisition of results. Cellular systems and transgenic animals have demonstrated their invaluable benefits. In this review, I present an overview of the methods of gene transfer with particular attention to cultured cell lines and large-scale sequence vectors, like artificial chromosomes, with the possibility of their manipulation based on homologous recombination strategies. Alternative strategies of gene transfer, including retroviral vectors, are also described and the applications of such methods are discussed. Finally, several comments are made about the influence of chromatin structure on gene expression. Recent experimental data have shown that for convenient stable transgene expression, the influence of chromatin structure should be seriously taken into account. Novel chromatin regulatory and structural elements are proposed as an alternative for proper and sustained gene expression. These chromatin elements are facing a new era in transgenesis and we are probably beginning a new generation of gene and cancer therapy vectors.
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Affiliation(s)
- Félix Recillas-Targa
- Instituto de Fisiología Celular, Departamento de Genética Molecular, Universidad Nacional Autónoma de México Apartado Postal 70-242, México D.F. 04510.
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32
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Abstract
Human immunodeficiency virus 1 (HIV-1) and other retroviruses synthesize a DNA copy of their genome after entry into the host cell. Integration of this DNA into the host cell's genome is an essential step in the viral replication cycle. The viral DNA is synthesized in the cytoplasm and is associated with viral and cellular proteins in a large nucleoprotein complex. Before integration into the host genome can occur, this complex must be transported to the nucleus and must cross the nuclear envelope. This Review summarizes our current knowledge of how this journey is accomplished.
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Affiliation(s)
- Youichi Suzuki
- Laboratory for Host Factors, Center for Emerging Virus Research, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawara-cho, Sakyo-ku, Kyoto 606-8507, Japan
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Abstract
Retroviruses make a long and complex journey from outside the cell to the nucleus in the early stages of infection, and then an equally long journey back out again in the late stages of infection. Ongoing efforts are identifying an enormous array of cellular proteins that are used by the viruses in the course of their travels. These host factors are potential new targets for therapeutic intervention.
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Affiliation(s)
- Stephen P Goff
- Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute HHSC 1310c, College of Physicians and Surgeons, Columbia University, 701 West 168th Street, New York, New York 10032, USA.
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Vaughan EE, DeGiulio JV, Dean DA. Intracellular trafficking of plasmids for gene therapy: mechanisms of cytoplasmic movement and nuclear import. Curr Gene Ther 2007; 6:671-681. [PMID: 17168698 PMCID: PMC4400175 DOI: 10.2174/156652306779010688] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Under physiologically relevant conditions, the levels of non-viral gene transfer are low at best. The reason for this is that many barriers exist for the efficient transfer of genes to cells, even before any gene expression can occur. While many transfection strategies focus on DNA condensation and overcoming the plasma membrane, events associated with the intracellular trafficking of the DNA complexes have not been as extensively studied. Once internalized, plasmids must travel potentially long distances through the cytoplasm to reach their next barrier, the nuclear envelope. This review summarizes the current progress on the cytoplasmic trafficking and nuclear transport of plasmids used for gene therapy applications. Both of these processes utilize specific and defined mechanisms to facilitate movement of DNA complexes through the cell. The continued elucidation and exploitation of these mechanisms will lead to improved strategies for transfection and successful gene therapy.
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Affiliation(s)
| | | | - David A. Dean
- Address correspondence to this author at the Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, 240 E. Huron Ave., McGaw M-300, Chicago IL 60611 USA; Tel: 312-503-3121; Fax: 312-908-4650;
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35
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Lechardeur D, Lukacs GL. Nucleocytoplasmic transport of plasmid DNA: a perilous journey from the cytoplasm to the nucleus. Hum Gene Ther 2006; 17:882-9. [PMID: 16972756 DOI: 10.1089/hum.2006.17.882] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Nonviral vectors represent a promising approach for the safe delivery of therapeutic DNA in genetic and acquired human diseases. Before synthetic vector systems can be used for clinical applications, their limited efficacy must be addressed. At the cellular level, successful gene transfer is dependent on several additional factors including DNA uptake, release from the DNA-vector complex, and nucleocytoplasmic transport. This paper reviews the major metabolic and physical impediments that plasmid DNA vectorized by synthetic vectors encounters between the cytosol and the nucleus. Plasmid DNA that escapes the endolysosomal compartment encounters the diffusional and metabolic barriers of the cytoplasm, reducing the number of intact plasmids that reach the nuclear envelope. Nuclear translocation of DNA requires either the disassembly of the nuclear envelope during cell division or active nuclear transport via the nuclear pore complex. In the nucleus, plasmid DNA is relatively stable, but its transcription and its fate during cell division are still debated. A better understanding of the cellular and molecular basis of nonviral gene transfer during nucleocytoplasmic trafficking may provide strategies to overcome those obstacles that limit the efficiency of nonviral gene delivery. We review some of the current methods of gene transfer mediated by synthetic vectors, highlighting systems that exploit our actual knowledge of the nucleocytoplasmic transport of plasmid DNA.
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Affiliation(s)
- Delphine Lechardeur
- Hospital for Sick Children, Program in Cell and Lung Biology, Department of Biochemistry and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, M5G 1X8 Canada.
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Yu JH, Schaffer DV. High-throughput, library-based selection of a murine leukemia virus variant to infect nondividing cells. J Virol 2006; 80:8981-8. [PMID: 16940510 PMCID: PMC1563944 DOI: 10.1128/jvi.00615-06] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gammaretroviruses, such as murine leukemia virus (MLV), are functionally distinguished from lentiviruses, such as human immunodeficiency virus, by their inability to infect nondividing cells. Attempts to engineer this property into MLV have been hindered by an incomplete understanding of early events in the viral life cycle. We utilized a transposon-based method to generate saturated peptide insertion libraries of MLV gag-pol variants with nuclear localization signals randomly incorporated throughout these overlapping genes. High-throughput selection of the libraries via iterative retroviral infection of nondividing cells led to the identification of a novel variant that successfully transduced growth-arrested cells. Vector packaging by cotransfection of the gag-pol.NLS variant with wild-type gag-pol produced high-titer virions capable of infecting neurons in vitro and in vivo. The capacity of mutant virions to transduce nondividing cells could help to elucidate incompletely understood mechanisms of the viral life cycle and greatly broaden the gene therapy applications of retroviral vectors. Furthermore, the ability to engineer key intracellular viral infection steps has potential implications for the understanding, design, and control of other post-entry events. Finally, this method of library generation and selection for a desired phenotype directly in a mammalian system can be readily expanded to address other challenges in protein engineering.
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Affiliation(s)
- Julie H Yu
- Department of Chemical Engineering, University of California-Berkeley, 201 Gilman Hall, Berkeley, CA 94720-1462, USA
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Lechardeur D, Lukacs GL. Nucleocytoplasmic Transport of Plasmid DNA: A Perilous Journey from the Cytoplasm to the Nucleus. Hum Gene Ther 2006. [DOI: 10.1089/hum.2006.17.ft-238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Baum C, Schambach A, Bohne J, Galla M. Retrovirus Vectors: Toward the Plentivirus? Mol Ther 2006; 13:1050-63. [PMID: 16632409 DOI: 10.1016/j.ymthe.2006.03.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 03/16/2006] [Accepted: 03/16/2006] [Indexed: 01/19/2023] Open
Abstract
Recombinant retroviral vectors based upon simple gammaretroviruses, complex lentiviruses, or potentially nonpathogenic spumaviruses represent relatively well characterized tools that are widely used for stable gene transfer. Different members of the Retroviridae family have developed distinct and potentially useful features related to their life cycle. These natural differences can be exploited for specialized applications in gene therapy and could conceivably be combined to create future retroviral hybrid vectors, ideally incorporating the following features: an efficient, noncytopathic packaging system with low likelihood of recombination; serum resistance; an ability to pseudotype with cell-specific envelopes; high-fidelity reverse transcription before cell entry; unrestricted cytoplasmic transport and nuclear import; an insulated expression cassette; specific chromosomal targeting; and physiologic or regulated levels of transgene expression. We envisage that, compared to contemporary vectors, a hybrid vector combining these properties would have increased therapeutic efficacy and an enhanced biosafety profile. Many of the above goals will require the inclusion of nonretroviral components into vector particles or transgenes.
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Affiliation(s)
- Christopher Baum
- Department of Experimental Hematology, Hannover Medical School, D-30625 Hannover, Germany.
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