1
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Cheng HLM. A primer on in vivo cell tracking using MRI. Front Med (Lausanne) 2023; 10:1193459. [PMID: 37324153 PMCID: PMC10264782 DOI: 10.3389/fmed.2023.1193459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/12/2023] [Indexed: 06/17/2023] Open
Abstract
Cell tracking by in vivo magnetic resonance imaging (MRI) offers a collection of multiple advantages over other imaging modalities, including high spatial resolution, unlimited depth penetration, 3D visualization, lack of ionizing radiation, and the potential for long-term cell monitoring. Three decades of innovation in both contrast agent chemistry and imaging physics have built an expansive array of probes and methods to track cells non-invasively across a diverse range of applications. In this review, we describe both established and emerging MRI cell tracking approaches and the variety of mechanisms available for contrast generation. Emphasis is given to the advantages, practical limitations, and persistent challenges of each approach, incorporating quantitative comparisons where possible. Toward the end of this review, we take a deeper dive into three key application areas - tracking cancer metastasis, immunotherapy for cancer, and stem cell regeneration - and discuss the cell tracking techniques most suitable to each.
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Affiliation(s)
- Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
- Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, ON, Canada
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2
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Tsintou M, Dalamagkas K, Moore TL, Rathi Y, Kubicki M, Rosene DL, Makris N. The use of hydrogel-delivered extracellular vesicles in recovery of motor function in stroke: a testable experimental hypothesis for clinical translation including behavioral and neuroimaging assessment approaches. Neural Regen Res 2021; 16:605-613. [PMID: 33063708 PMCID: PMC8067932 DOI: 10.4103/1673-5374.295269] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neural tissue engineering, nanotechnology and neuroregeneration are diverse biomedical disciplines that have been working together in recent decades to solve the complex problems linked to central nervous system (CNS) repair. It is known that the CNS demonstrates a very limited regenerative capacity because of a microenvironment that impedes effective regenerative processes, making development of CNS therapeutics challenging. Given the high prevalence of CNS conditions such as stroke that damage the brain and place a severe burden on afflicted individuals and on society, it is of utmost significance to explore the optimum methodologies for finding treatments that could be applied to humans for restoration of function to pre-injury levels. Extracellular vesicles (EVs), also known as exosomes, when derived from mesenchymal stem cells, are one of the most promising approaches that have been attempted thus far, as EVs deliver factors that stimulate recovery by acting at the nanoscale level on intercellular communication while avoiding the risks linked to stem cell transplantation. At the same time, advances in tissue engineering and regenerative medicine have offered the potential of using hydrogels as bio-scaffolds in order to provide the stroma required for neural repair to occur, as well as the release of biomolecules facilitating or inducing the reparative processes. This review introduces a novel experimental hypothesis regarding the benefits that could be offered if EVs were to be combined with biocompatible injectable hydrogels. The rationale behind this hypothesis is presented, analyzing how a hydrogel might prolong the retention of EVs and maximize the localized benefit to the brain. This sustained delivery of EVs would be coupled with essential guidance cues and structural support from the hydrogel until neural tissue remodeling and regeneration occur. Finally, the importance of including non-human primate models in the clinical translation pipeline, as well as the added benefit of multi-modal neuroimaging analysis to establish non-invasive, in vivo, quantifiable imaging-based biomarkers for CNS repair are discussed, aiming for more effective and safe clinical translation of such regenerative therapies to humans.
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Affiliation(s)
- Magdalini Tsintou
- Department of Psychiatry and Neurology Services, Center for Neural Systems Investigations, Center for Morphometric Analysis, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital; Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; University College of London Division of Surgery & Interventional Science, Center for Nanotechnology & Regenerative Medicine, University College London, London, UK
| | - Kyriakos Dalamagkas
- University College of London Division of Surgery & Interventional Science, Center for Nanotechnology & Regenerative Medicine, University College London, London, UK; Department of Physical Medicine and Rehabilitation, The University of Texas Health Science Center at Houston; The Institute for Rehabilitation and Research Memorial Hermann Research Center, The Institute for Rehabilitation and Research Memorial Hermann Hospital, Houston, TX, USA
| | - Tara L Moore
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - Yogesh Rathi
- Department of Psychiatry and Neurology Services, Center for Neural Systems Investigations, Center for Morphometric Analysis, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital; Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Marek Kubicki
- Department of Psychiatry and Neurology Services, Center for Neural Systems Investigations, Center for Morphometric Analysis, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital; Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Douglas L Rosene
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - Nikos Makris
- Department of Psychiatry and Neurology Services, Center for Neural Systems Investigations, Center for Morphometric Analysis, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital; Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School; Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, USA
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3
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Pekarsky A, Spadiut O. Intrinsically Magnetic Cells: A Review on Their Natural Occurrence and Synthetic Generation. Front Bioeng Biotechnol 2020; 8:573183. [PMID: 33195134 PMCID: PMC7604359 DOI: 10.3389/fbioe.2020.573183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 09/29/2020] [Indexed: 12/31/2022] Open
Abstract
The magnetization of non-magnetic cells has great potential to aid various processes in medicine, but also in bioprocess engineering. Current approaches to magnetize cells with magnetic nanoparticles (MNPs) require cellular uptake or adsorption through in vitro manipulation of cells. A relatively new field of research is "magnetogenetics" which focuses on in vivo production and accumulation of magnetic material. Natural intrinsically magnetic cells (IMCs) produce intracellular, MNPs, and are called magnetotactic bacteria (MTB). In recent years, researchers have unraveled function and structure of numerous proteins from MTB. Furthermore, protein engineering studies on such MTB proteins and other potentially magnetic proteins, like ferritins, highlight that in vivo magnetization of non-magnetic hosts is a thriving field of research. This review summarizes current knowledge on recombinant IMC generation and highlights future steps that can be taken to succeed in transforming non-magnetic cells to IMCs.
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Affiliation(s)
| | - Oliver Spadiut
- Institute of Chemical, Environmental and Bioscience Engineering, Research Area Biochemical Engineering, Technische Universität Wien, Vienna, Austria
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4
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Rahman A, Lin J, Jaramillo FE, Bazylinski DA, Jeffryes C, Dahoumane SA. In Vivo Biosynthesis of Inorganic Nanomaterials Using Eukaryotes-A Review. Molecules 2020; 25:E3246. [PMID: 32708767 PMCID: PMC7397067 DOI: 10.3390/molecules25143246] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/10/2020] [Accepted: 07/14/2020] [Indexed: 01/09/2023] Open
Abstract
Bionanotechnology, the use of biological resources to produce novel, valuable nanomaterials, has witnessed tremendous developments over the past two decades. This eco-friendly and sustainable approach enables the synthesis of numerous, diverse types of useful nanomaterials for many medical, commercial, and scientific applications. Countless reviews describing the biosynthesis of nanomaterials have been published. However, to the best of our knowledge, no review has been exclusively focused on the in vivo biosynthesis of inorganic nanomaterials. Therefore, the present review is dedicated to filling this gap by describing the many different facets of the in vivo biosynthesis of nanoparticles (NPs) using living eukaryotic cells and organisms-more specifically, live plants and living biomass of several species of microalgae, yeast, fungus, mammalian cells, and animals. It also highlights the strengths and weaknesses of the synthesis methodologies and the NP characteristics, bio-applications, and proposed synthesis mechanisms. This comprehensive review also brings attention to enabling a better understanding between the living organisms themselves and the synthesis conditions that allow their exploitation as nanobiotechnological production platforms as these might serve as a robust resource to boost and expand the bio-production and use of desirable, functional inorganic nanomaterials.
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Affiliation(s)
- Ashiqur Rahman
- Center for Midstream Management and Science, Lamar University, Beaumont, TX 77710, USA;
- Center for Advances in Water and Air Quality & The Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX 77710, USA; (J.L.); (C.J.)
| | - Julia Lin
- Center for Advances in Water and Air Quality & The Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX 77710, USA; (J.L.); (C.J.)
| | - Francisco E. Jaramillo
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100119, Ecuador;
| | - Dennis A. Bazylinski
- School of Life Sciences, University of Nevada at Las Vegas, Las Vegas, NV 89154-4004, USA;
| | - Clayton Jeffryes
- Center for Advances in Water and Air Quality & The Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX 77710, USA; (J.L.); (C.J.)
| | - Si Amar Dahoumane
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San José s/n, San Miguel de Urcuquí 100119, Ecuador;
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5
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Alizadeh K, Sun Q, McGuire T, Thompson T, Prato FS, Koropatnick J, Gelman N, Goldhawk DE. Hepcidin-mediated Iron Regulation in P19 Cells is Detectable by Magnetic Resonance Imaging. Sci Rep 2020; 10:3163. [PMID: 32081948 PMCID: PMC7035373 DOI: 10.1038/s41598-020-59991-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 02/04/2020] [Indexed: 01/25/2023] Open
Abstract
Magnetic resonance imaging can be used to track cellular activities in the body using iron-based contrast agents. However, multiple intrinsic cellular iron handling mechanisms may also influence the detection of magnetic resonance (MR) contrast: a need to differentiate among those mechanisms exists. In hepcidin-mediated inflammation, for example, downregulation of iron export in monocytes and macrophages involves post-translational degradation of ferroportin. We examined the influence of hepcidin endocrine activity on iron regulation and MR transverse relaxation rates in multi-potent P19 cells, which display high iron import and export activities, similar to alternatively-activated macrophages. Iron import and export were examined in cultured P19 cells in the presence and absence of iron-supplemented medium, respectively. Western blots indicated the levels of transferrin receptor, ferroportin and ubiquitin in the presence and absence of extracellular hepcidin. Total cellular iron was measured by inductively-coupled plasma mass spectrometry and correlated to transverse relaxation rates at 3 Tesla using a gelatin phantom. Under varying conditions of iron supplementation, the level of ferroportin in P19 cells responds to hepcidin regulation, consistent with degradation through a ubiquitin-mediated pathway. This response of P19 cells to hepcidin is similar to that of classically-activated macrophages. The correlation between total cellular iron content and MR transverse relaxation rates was different in hepcidin-treated and untreated P19 cells: slope, Pearson correlation coefficient and relaxation rate were all affected. These findings may provide a tool to non-invasively distinguish changes in endogenous iron contrast arising from hepcidin-ferroportin interactions, with potential utility in monitoring of different macrophage phenotypes involved in pro- and anti-inflammatory signaling. In addition, this work demonstrates that transverse relaxivity is not only influenced by the amount of cellular iron but also by its metabolism.
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Affiliation(s)
- Kobra Alizadeh
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
| | - Qin Sun
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
| | - Tabitha McGuire
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
| | - Terry Thompson
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Medical Imaging, Western University, London, Ontario, Canada
- Physics and Astronomy, Western University, London, Ontario, Canada
| | - Frank S Prato
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
- Medical Imaging, Western University, London, Ontario, Canada
- Physics and Astronomy, Western University, London, Ontario, Canada
| | - Jim Koropatnick
- London Regional Cancer Program, London, Ontario, Canada
- Oncology, Western University, London, Ontario, Canada
| | - Neil Gelman
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Medical Imaging, Western University, London, Ontario, Canada
| | - Donna E Goldhawk
- Imaging, Lawson Health Research Institute, London, Ontario, Canada.
- Medical Biophysics, Western University, London, Ontario, Canada.
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada.
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6
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Liu L, Alizadeh K, Donnelly SC, Dassanayake P, Hou TT, McGirr R, Thompson RT, Prato FS, Gelman N, Hoffman L, Goldhawk DE. MagA expression attenuates iron export activity in undifferentiated multipotent P19 cells. PLoS One 2019; 14:e0217842. [PMID: 31170273 PMCID: PMC6553743 DOI: 10.1371/journal.pone.0217842] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 05/20/2019] [Indexed: 12/21/2022] Open
Abstract
Magnetic resonance imaging (MRI) is a non-invasive imaging modality used in longitudinal cell tracking. Previous studies suggest that MagA, a putative iron transport protein from magnetotactic bacteria, is a useful gene-based magnetic resonance contrast agent. Hemagglutinin-tagged MagA was stably expressed in undifferentiated embryonic mouse teratocarcinoma, multipotent P19 cells to provide a suitable model for tracking these cells during differentiation. Western blot and immunocytochemistry confirmed the expression and membrane localization of MagA in P19 cells. Surprisingly, elemental iron analysis using inductively-coupled plasma mass spectrometry revealed significant iron uptake in both parental and MagA-expressing P19 cells, cultured in the presence of iron-supplemented medium. Withdrawal of this extracellular iron supplement revealed unexpected iron export activity in P19 cells, which MagA expression attenuated. The influence of iron supplementation on parental and MagA-expressing cells was not reflected by longitudinal relaxation rates. Measurement of transverse relaxation rates (R2* and R2) reflected changes in total cellular iron content but did not clearly distinguish MagA-expressing cells from the parental cell type, despite significant differences in the uptake and retention of total cellular iron. Unlike other cell types, the reversible component R2′ (R2* ‒ R2) provided only a moderately strong correlation to amount of cellular iron, normalized to amount of protein. This is the first report to characterize MagA expression in a previously unrecognized iron exporting cell type. The interplay between contrast gene expression and systemic iron metabolism substantiates the potential for diverting cellular iron toward the formation of a novel iron compartment, however rudimentary when using a single magnetotactic bacterial gene expression system like magA. Since relatively few mammalian cells export iron, the P19 cell line provides a tractable model of ferroportin activity, suitable for magnetic resonance analysis of key iron-handling activities and their influence on gene-based MRI contrast.
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Affiliation(s)
- Linshan Liu
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
| | - Kobra Alizadeh
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
| | - Sarah C. Donnelly
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
- Microbiology and Immunology, Western University, London, Ontario, Canada
| | - Praveen Dassanayake
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
| | - Tian Tian Hou
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
| | - Rebecca McGirr
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
| | - R. Terry Thompson
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Medical Imaging, Western University, London, Ontario, Canada
- Physics and Astronomy, Western University, London, Ontario, Canada
| | - Frank S. Prato
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
- Medical Imaging, Western University, London, Ontario, Canada
- Physics and Astronomy, Western University, London, Ontario, Canada
| | - Neil Gelman
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Medical Imaging, Western University, London, Ontario, Canada
| | - Lisa Hoffman
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
- Anatomy and Cell Biology, Western University, London, Ontario, Canada
| | - Donna E. Goldhawk
- Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Medical Biophysics, Western University, London, Ontario, Canada
- Collaborative Graduate Program in Molecular Imaging, Western University, London, Ontario, Canada
- * E-mail:
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7
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Dieudonné A, Pignol D, Prévéral S. Magnetosomes: biogenic iron nanoparticles produced by environmental bacteria. Appl Microbiol Biotechnol 2019; 103:3637-3649. [PMID: 30903215 DOI: 10.1007/s00253-019-09728-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 02/22/2019] [Accepted: 02/25/2019] [Indexed: 01/10/2023]
Abstract
The scientific community's interest in magnetotactic bacteria has increased substantially in recent decades. These prokaryotes have the particularity of synthesizing nanomagnets, called magnetosomes. The majority of research is based on several scientific questions. Where do magnetotactic bacteria live, what are their characteristics, and why are they magnetic? What are the molecular phenomena of magnetosome biomineralization and what are the physical characteristics of magnetosomes? In addition to scientific curiosity to better understand these stunning organisms, there are biotechnological opportunities to consider. Magnetotactic bacteria, as well as magnetosomes, are used in medical applications, for example cancer treatment, or in environmental ones, for example bioremediation. In this mini-review, we investigated all the aspects mentioned above and summarized the currently available knowledge.
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Affiliation(s)
- Anissa Dieudonné
- UMR 7265, Aix Marseille Univ, CEA, CNRS, BIAM, LBC, Saint Paul-Lez-Durance, France
| | - David Pignol
- UMR 7265, Aix Marseille Univ, CEA, CNRS, BIAM, LBC, Saint Paul-Lez-Durance, France
| | - Sandra Prévéral
- UMR 7265, Aix Marseille Univ, CEA, CNRS, BIAM, LBC, Saint Paul-Lez-Durance, France.
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8
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He X, Cai J, Li H, Liu B, Qin Y, Zhong Y, Wang L, Liao Y. In Vivo magnetic resonance imaging of xenografted tumors using FTH1 reporter gene expression controlled by a tet-on switch. Oncotarget 2018; 7:78591-78604. [PMID: 27732930 PMCID: PMC5346662 DOI: 10.18632/oncotarget.12519] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 10/03/2016] [Indexed: 12/28/2022] Open
Abstract
As a promising magnetic resonance imaging (MRI) reporter, ferritin has been used to track cells in vivo; however, its continuous overexpression can be cytotoxic, which restricts its application. In this study, we aimed to develop a switch to turn this genetic reporter “on” or “off” while monitoring cell grafts via MRI. To accomplish this, we genetically modified the ferritin heavy chain (FTH1) with a Tet-On switch and assessed the expression of FTH1 in transduced neuroblastoma cells (SK-N-SH) in vitro and in xenografted tumors in vivo. We found that FTH1 expression induced by doxycycline (Dox) in SK-N-SH-FTH1 cells depended on treatment dose and duration. We successfully detected T2-weighted MRI contrast in cell grafts after switching “on” the reporter gene using Dox, and this contrast disappeared when we switched it “off”. The genetic reporter FTH1 can thus be switched “on” or “off” throughout longitudinal monitoring of cell grafts, limiting expression to when MRI contrast is needed. The controllable imaging system we have developed minimizes risks from constitutive reporter gene overexpression and facilitates tumor cell monitoring in vitro and in vivo.
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Affiliation(s)
- Xiaoya He
- Department of Radiology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Jinhua Cai
- Department of Radiology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Hao Li
- Department of Radiology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Bo Liu
- Department of Radiology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Yong Qin
- Department of Radiology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Yi Zhong
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Longlun Wang
- Department of Radiology, Children's Hospital of Chongqing Medical University, Chongqing, China.,Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Yifan Liao
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China.,Key Laboratory of Pediatrics in Chongqing, Chongqing, China.,Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
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9
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Elfick A, Rischitor G, Mouras R, Azfer A, Lungaro L, Uhlarz M, Herrmannsdörfer T, Lucocq J, Gamal W, Bagnaninchi P, Semple S, Salter DM. Biosynthesis of magnetic nanoparticles by human mesenchymal stem cells following transfection with the magnetotactic bacterial gene mms6. Sci Rep 2017; 7:39755. [PMID: 28051139 PMCID: PMC5209691 DOI: 10.1038/srep39755] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 11/28/2016] [Indexed: 12/23/2022] Open
Abstract
The use of stem cells to support tissue repair is facilitated by loading of the therapeutic cells with magnetic nanoparticles (MNPs) enabling magnetic tracking and targeting. Current methods for magnetizing cells use artificial MNPs and have disadvantages of variable uptake, cellular cytotoxicity and loss of nanoparticles on cell division. Here we demonstrate a transgenic approach to magnetize human mesenchymal stem cells (MSCs). MSCs are genetically modified by transfection with the mms6 gene derived from Magnetospirillum magneticum AMB-1, a magnetotactic bacterium that synthesises single-magnetic domain crystals which are incorporated into magnetosomes. Following transfection of MSCs with the mms6 gene there is bio-assimilated synthesis of intracytoplasmic magnetic nanoparticles which can be imaged by MR and which have no deleterious effects on cell proliferation, migration or differentiation. The assimilation of magnetic nanoparticle synthesis into mammalian cells creates a real and compelling, cytocompatible, alternative to exogenous administration of MNPs.
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Affiliation(s)
- Alistair Elfick
- University of Edinburgh, Institute for Bioengineering, School of Engineering, Edinburgh, EH9 3FB, UK
- University of Edinburgh, UK Centre for Mammalian Synthetic Biology, Edinburgh, EH9 3FB, UK
| | - Grigore Rischitor
- University of Edinburgh, Centre for Genomics and Experimental Medicine, MRC IGMM, Edinburgh, EH4 2XU, UK
| | - Rabah Mouras
- University of Edinburgh, Institute for Bioengineering, School of Engineering, Edinburgh, EH9 3FB, UK
| | - Asim Azfer
- University of Edinburgh, Centre for Genomics and Experimental Medicine, MRC IGMM, Edinburgh, EH4 2XU, UK
| | - Lisa Lungaro
- University of Edinburgh, Institute for Bioengineering, School of Engineering, Edinburgh, EH9 3FB, UK
- University of Edinburgh, Centre for Genomics and Experimental Medicine, MRC IGMM, Edinburgh, EH4 2XU, UK
| | - Marc Uhlarz
- Helmholtz-Zentrum Dresden-Rossendorf, Dresden High Magnetic Field Laboratory (HLD-EMFL), Dresden, 01328, Germany
| | - Thomas Herrmannsdörfer
- Helmholtz-Zentrum Dresden-Rossendorf, Dresden High Magnetic Field Laboratory (HLD-EMFL), Dresden, 01328, Germany
| | - John Lucocq
- University of St Andrews, School of Medicine, St Andrews, KY16 9TF, UK
| | - Wesam Gamal
- University of Edinburgh, Centre for Regenerative Medicine, Edinburgh, EH16 4UU, UK
| | - Pierre Bagnaninchi
- University of Edinburgh, Centre for Regenerative Medicine, Edinburgh, EH16 4UU, UK
| | - Scott Semple
- University of Edinburgh, Centre for Cardiovascular Science, Edinburgh, EH16 4TJ UK
| | - Donald M Salter
- University of Edinburgh, Centre for Genomics and Experimental Medicine, MRC IGMM, Edinburgh, EH4 2XU, UK
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10
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Cho IK, Wang S, Mao H, Chan AWS. Genetic engineered molecular imaging probes for applications in cell therapy: emphasis on MRI approach. AMERICAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING 2016; 6:234-261. [PMID: 27766183 PMCID: PMC5069277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 08/31/2016] [Indexed: 06/06/2023]
Abstract
Recent advances in stem cell-based regenerative medicine, cell replacement therapy, and genome editing technologies (i.e. CRISPR-Cas 9) have sparked great interest in in vivo cell monitoring. Molecular imaging promises a unique approach to noninvasively monitor cellular and molecular phenomena, including cell survival, migration, proliferation, and even differentiation at the whole organismal level. Several imaging modalities and strategies have been explored for monitoring cell grafts in vivo. We begin this review with an introduction describing the progress in stem cell technology, with a perspective toward cell replacement therapy. The importance of molecular imaging in reporting and assessing the status of cell grafts and their relation to the local microenvironment is highlighted since the current knowledge gap is one of the major obstacles in clinical translation of stem cell therapy. Based on currently available imaging techniques, we provide a brief discussion on the pros and cons of each imaging modality used for monitoring cell grafts with particular emphasis on magnetic resonance imaging (MRI) and the reporter gene approach. Finally, we conclude with a comprehensive discussion of future directions of applying molecular imaging in regenerative medicine to emphasize further the importance of correlating cell graft conditions and clinical outcomes to advance regenerative medicine.
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Affiliation(s)
- In K Cho
- Department of Human Genetics, Emory University School of MedicineAtlanta, GA, USA
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research CenterAtlanta, GA, USA
| | - Silun Wang
- Department of Radiology and Imaging Sciences, Emory University School of MedicineAtlanta, GA, USA
| | - Hui Mao
- Department of Radiology and Imaging Sciences, Emory University School of MedicineAtlanta, GA, USA
| | - Anthony WS Chan
- Department of Human Genetics, Emory University School of MedicineAtlanta, GA, USA
- Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research CenterAtlanta, GA, USA
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11
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Radoul M, Lewin L, Cohen B, Oren R, Popov S, Davidov G, Vandsburger MH, Harmelin A, Bitton R, Greneche JM, Neeman M, Zarivach R. Genetic manipulation of iron biomineralization enhances MR relaxivity in a ferritin-M6A chimeric complex. Sci Rep 2016; 6:26550. [PMID: 27211820 PMCID: PMC4876375 DOI: 10.1038/srep26550] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 05/04/2016] [Indexed: 01/07/2023] Open
Abstract
Ferritin has gained significant attention as a potential reporter gene for in vivo imaging by magnetic resonance imaging (MRI). However, due to the ferritin ferrihydrite core, the relaxivity and sensitivity for detection of native ferritin is relatively low. We report here on a novel chimeric magneto-ferritin reporter gene - ferritin-M6A - in which the magnetite binding peptide from the magnetotactic bacteria magnetosome-associated Mms6 protein was fused to the C-terminal of murine h-ferritin. Biophysical experiments showed that purified ferritin-M6A assembled into a stable protein cage with the M6A protruding into the cage core, enabling magnetite biomineralisation. Ferritin-M6A-expressing C6-glioma cells showed enhanced (per iron) r2 relaxivity. MRI in vivo studies of ferritin-M6A-expressing tumour xenografts showed enhanced R2 relaxation rate in the central hypoxic region of the tumours. Such enhanced relaxivity would increase the sensitivity of ferritin as a reporter gene for non-invasive in vivo MRI-monitoring of cell delivery and differentiation in cellular or gene-based therapies.
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Affiliation(s)
- Marina Radoul
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100 Israel
| | - Limor Lewin
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, POB 653, Beer-Sheva 84105, Israel
| | - Batya Cohen
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100 Israel
| | - Roni Oren
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100 Israel
| | - Stanislav Popov
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, POB 653, Beer-Sheva 84105, Israel
| | - Geula Davidov
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, POB 653, Beer-Sheva 84105, Israel
| | - Moriel H. Vandsburger
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100 Israel
| | - Alon Harmelin
- Department of Veterinary Resources, Weizmann Institute of Science, Rehovot 76100 Israel
| | - Ronit Bitton
- Department of Chemical Engineering and Ilse Katz Institute for Nanoscale Science and Technology Ben-Gurion University of the Negev, 84105 Beer-Sheva, Israel
| | - Jean-Marc Greneche
- Institut des Molécules et Matériaux du Mans (IMMM), UMR CNRS 6283 Université du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex France
| | - Michal Neeman
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100 Israel,
| | - Raz Zarivach
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, POB 653, Beer-Sheva 84105, Israel,
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12
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Pereira SM, Williams SR, Murray P, Taylor A. MS-1 magA: Revisiting Its Efficacy as a Reporter Gene for MRI. Mol Imaging 2016; 15:15/0/1536012116641533. [PMID: 27118760 PMCID: PMC5470133 DOI: 10.1177/1536012116641533] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/25/2016] [Indexed: 12/30/2022] Open
Abstract
Bacterial genes involved in the biomineralization of magnetic nanoparticles in magnetotactic bacteria have recently been proposed as reporters for magnetic resonance imaging (MRI). In such systems, the expression of the bacterial genes in mammalian cells purportedly leads to greater concentrations of intracellular iron or the biomineralization of iron oxides, thus leading to an enhancement in relaxation rate that is detectable via MRI. Here, we show that the constitutive expression of the magA gene from Magnetospirillum magnetotacticum is tolerated by human embryonic kidney (HEK) cells but induces a strong toxic effect in murine mesenchymal/stromal cells and kidney-derived stem cells, severely restricting its effective use as a reporter gene for stem cells. Although it has been suggested that magA is involved in iron transport, when expressed in HEK cells, it does not affect the transcription of endogenous genes related to iron homeostasis. Furthermore, the magA-induced enhancement in iron uptake in HEK cells is insignificant, suggesting this gene is a poor reporter even for cell types that can tolerate its expression. We suggest that the use of magA for stem cells should be approached with caution, and its efficacy as a reporter gene requires a careful assessment on a cell-by-cell basis.
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Affiliation(s)
- Sofia M Pereira
- Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, United Kingdom
| | - Steve R Williams
- Centre for Imaging Sciences, University of Manchester, Oxford Road, Manchester, United Kingdom
| | - Patricia Murray
- Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, United Kingdom
| | - Arthur Taylor
- Institute of Translational Medicine, University of Liverpool, Crown Street, Liverpool, United Kingdom
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13
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He X, Cai J, Liu B, Zhong Y, Qin Y. Cellular magnetic resonance imaging contrast generated by the ferritin heavy chain genetic reporter under the control of a Tet-On switch. Stem Cell Res Ther 2015; 6:207. [PMID: 26517988 PMCID: PMC4628232 DOI: 10.1186/s13287-015-0205-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 08/30/2015] [Accepted: 10/16/2015] [Indexed: 12/26/2022] Open
Abstract
INTRODUCTION Despite the strong appeal of ferritin as a magnetic resonance imaging (MRI) reporter for stem cell research, no attempts have been made to apply this genetic imaging reporter in stem cells in an inducible manner, which is important for minimizing the potential risk related to the constitutive expression of an imaging reporter. The aim of the present study was to develop an inducible genetic MRI reporter system that enables the production of intracellular MRI contrast as needed. METHODS Ferritin heavy chain (FTH1) was genetically modified by adding a Tet-On switch. A C3H10T1/2 cell line carrying Tet-FTH1 (C3H10T1/2-FTH1) was established via lentiviral transduction. The dose- and time-dependent expression of FTH1 in C3H10T1/2 cells was assessed by western blot and immunofluorescence staining. The induced "ON" and non-induced "OFF" expressions of FTH1 were detected using a 3.0 T MRI scanner. Iron accumulation in cells was analyzed by Prussian blue staining and transmission electron microscopy (TEM). RESULTS The expression of FTH1 was both dose- and time-dependently induced, and FTH1 expression peaked in response to induction with doxycycline (Dox) at 0.2 μg/ml for 72 h. The induced expression of FTH1 resulted in a significant increase in the transverse relaxation rate of C3H10T1/2-FTH1 cells following iron supplementation. Prussian blue staining and TEM revealed extensive iron accumulation in C3H10T1/2-FTH1 cells in the presence of Dox. CONCLUSIONS Cellular MRI contrast can be produced as needed via the expression of FTH1 under the control of a Tet-On switch. This finding could lay the groundwork for the use of FTH1 to track stem cells in vivo in an inducible manner.
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Affiliation(s)
- Xiaoya He
- Department of Radiology, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Ministry of Education Key Laboratory of Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Key Laboratory of Pediatrics in Chongqing, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Chongqing International Science and Technology Cooperation Center For Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China.
| | - Jinhua Cai
- Department of Radiology, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Ministry of Education Key Laboratory of Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Key Laboratory of Pediatrics in Chongqing, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Chongqing International Science and Technology Cooperation Center For Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China.
| | - Bo Liu
- Department of Radiology, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Ministry of Education Key Laboratory of Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Key Laboratory of Pediatrics in Chongqing, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Chongqing International Science and Technology Cooperation Center For Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China.
| | - Yi Zhong
- Department of Radiology, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Ministry of Education Key Laboratory of Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Key Laboratory of Pediatrics in Chongqing, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Chongqing International Science and Technology Cooperation Center For Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China.
| | - Yong Qin
- Department of Radiology, Children's Hospital of Chongqing Medical University, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Ministry of Education Key Laboratory of Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Key Laboratory of Pediatrics in Chongqing, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China. .,Chongqing International Science and Technology Cooperation Center For Child Development and Disorders, 136 Zhongshan 2 Road, Yuzhong District, Chongqing, 400014, China.
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14
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Goldhawk DE, Gelman N, Sengupta A, Prato FS. The Interface Between Iron Metabolism and Gene-Based Iron Contrast for MRI. MAGNETIC RESONANCE INSIGHTS 2015; 8:9-14. [PMID: 26483608 PMCID: PMC4597585 DOI: 10.4137/mri.s23555] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/27/2015] [Accepted: 08/28/2015] [Indexed: 01/27/2023]
Abstract
Using a gene-based approach to track cellular and molecular activity with magnetic resonance imaging (MRI) has many advantages. The strong correlation between transverse relaxation rates and total cellular iron content provides a basis for developing sensitive and quantitative detection of MRI reporter gene expression. In addition to biophysical concepts, general features of mammalian iron regulation add valuable context for interpreting molecular MRI predicated on gene-based iron labeling. With particular reference to the potential of magnetotactic bacterial gene expression as a magnetic resonance (MR) contrast agent for mammalian cell tracking, studies in different cell culture models highlight the influence of intrinsic iron regulation on the MRI signal. The interplay between dynamic regulation of mammalian iron metabolism and expression systems designed to sequester iron biominerals for MRI is presented from the perspective of their potential influence on MR image interpretation.
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Affiliation(s)
- Donna E Goldhawk
- Imaging Program, Lawson Health Research Institute, London, Canada. ; Medical Biophysics, Western University, London, Canada. ; Collaborative Graduate Program in Molecular Imaging, Western University, London, Canada
| | - Neil Gelman
- Imaging Program, Lawson Health Research Institute, London, Canada. ; Medical Biophysics, Western University, London, Canada
| | - Anindita Sengupta
- Imaging Program, Lawson Health Research Institute, London, Canada. ; Medical Biophysics, Western University, London, Canada. ; Collaborative Graduate Program in Molecular Imaging, Western University, London, Canada
| | - Frank S Prato
- Imaging Program, Lawson Health Research Institute, London, Canada. ; Medical Biophysics, Western University, London, Canada
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15
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Cho IK, Moran SP, Paudyal R, Piotrowska-Nitsche K, Cheng PH, Zhang X, Mao H, Chan AW. Longitudinal monitoring of stem cell grafts in vivo using magnetic resonance imaging with inducible maga as a genetic reporter. Am J Cancer Res 2014; 4:972-89. [PMID: 25161700 PMCID: PMC4143941 DOI: 10.7150/thno.9436] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 06/29/2014] [Indexed: 01/06/2023] Open
Abstract
PURPOSE The ability to longitudinally monitor cell grafts and assess their condition is critical for the clinical translation of stem cell therapy in regenerative medicine. Developing an inducible genetic magnetic resonance imaging (MRI) reporter will enable non-invasive and longitudinal monitoring of stem cell grafts in vivo. METHODS MagA, a bacterial gene involved in the formation of iron oxide nanocrystals, was genetically modified for in vivo monitoring of cell grafts by MRI. Inducible expression of MagA was regulated by a Tet-On (Tet) switch. A mouse embryonic stem cell-line carrying Tet-MagA (mESC-MagA) was established by lentivirus transduction. The impact of expressing MagA in mESCs was evaluated via proliferation assay, cytotoxicity assay, teratoma formation, MRI, and inductively coupled plasma atomic emission spectroscopy (ICP-OES). Mice were grafted with mESCs with and without MagA (mESC-MagA and mESC-WT). The condition of cell grafts with induced "ON" and non-induced "OFF" expression of MagA was longitudinally monitored in vivo using a 7T MRI scanner. After imaging, whole brain samples were harvested for histological assessment. RESULTS Expression of MagA in mESCs resulted in significant changes in the transverse relaxation rate (R2 or 1/T2) and susceptibility weighted MRI contrast. The pluripotency of mESCs carrying MagA was not affected in vitro or in vivo. Intracranial mESC-MagA grafts generated sufficient T2 and susceptibility weighted contrast at 7T. The mESC-MagA grafts can be monitored by MRI longitudinally upon induced expression of MagA by administering doxycycline (Dox) via diet. CONCLUSION Our results demonstrate MagA could be used to monitor cell grafts noninvasively, longitudinally, and repetitively, enabling the assessment of cell graft conditions in vivo.
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