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Busch M, Brouwer H, Aalderink G, Bredeck G, Kämpfer AAM, Schins RPF, Bouwmeester H. Investigating nanoplastics toxicity using advanced stem cell-based intestinal and lung in vitro models. FRONTIERS IN TOXICOLOGY 2023; 5:1112212. [PMID: 36777263 PMCID: PMC9911716 DOI: 10.3389/ftox.2023.1112212] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 01/17/2023] [Indexed: 01/28/2023] Open
Abstract
Plastic particles in the nanometer range-called nanoplastics-are environmental contaminants with growing public health concern. As plastic particles are present in water, soil, air and food, human exposure via intestine and lung is unavoidable, but possible health effects are still to be elucidated. To better understand the Mode of Action of plastic particles, it is key to use experimental models that best reflect human physiology. Novel assessment methods like advanced cell models and several alternative approaches are currently used and developed in the scientific community. So far, the use of cancer cell line-based models is the standard approach regarding in vitro nanotoxicology. However, among the many advantages of the use of cancer cell lines, there are also disadvantages that might favor other approaches. In this review, we compare cell line-based models with stem cell-based in vitro models of the human intestine and lung. In the context of nanoplastics research, we highlight the advantages that come with the use of stem cells. Further, the specific challenges of testing nanoplastics in vitro are discussed. Although the use of stem cell-based models can be demanding, we conclude that, depending on the research question, stem cells in combination with advanced exposure strategies might be a more suitable approach than cancer cell lines when it comes to toxicological investigation of nanoplastics.
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Affiliation(s)
- Mathias Busch
- Division of Toxicology, Wageningen University and Research, Wageningen, Netherlands
| | - Hugo Brouwer
- Division of Toxicology, Wageningen University and Research, Wageningen, Netherlands
| | - Germaine Aalderink
- Division of Toxicology, Wageningen University and Research, Wageningen, Netherlands
| | - Gerrit Bredeck
- IUF—Leibniz-Research Institute for Environmental Medicine, Duesseldorf, Germany
| | | | - Roel P. F. Schins
- IUF—Leibniz-Research Institute for Environmental Medicine, Duesseldorf, Germany
| | - Hans Bouwmeester
- Division of Toxicology, Wageningen University and Research, Wageningen, Netherlands,*Correspondence: Hans Bouwmeester,
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2
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Lim HJ, Wubben JM, Garcia CP, Cruz-Gomez S, Deng J, Mak JY, Hachani A, Anderson RJ, Painter GF, Goyette J, Amarasinghe SL, Ritchie ME, Roquilly A, Fairlie DP, Gaus K, Rossjohn J, Villadangos JA, McWilliam HE. A specialized tyrosine-based endocytosis signal in MR1 controls antigen presentation to MAIT cells. J Cell Biol 2022; 221:213489. [PMID: 36129434 PMCID: PMC9499830 DOI: 10.1083/jcb.202110125] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 06/23/2022] [Accepted: 09/01/2022] [Indexed: 12/13/2022] Open
Abstract
MR1 is a highly conserved microbial immune-detection system in mammals. It captures vitamin B-related metabolite antigens from diverse microbes and presents them at the cell surface to stimulate MR1-restricted lymphocytes including mucosal-associated invariant T (MAIT) cells. MR1 presentation and MAIT cell recognition mediate homeostasis through host defense and tissue repair. The cellular mechanisms regulating MR1 cell surface expression are critical to its function and MAIT cell recognition, yet they are poorly defined. Here, we report that human MR1 is equipped with a tyrosine-based motif in its cytoplasmic domain that mediates low affinity binding with the endocytic adaptor protein 2 (AP2) complex. This interaction controls the kinetics of MR1 internalization from the cell surface and minimizes recycling. We propose MR1 uses AP2 endocytosis to define the duration of antigen presentation to MAIT cells and the detection of a microbial metabolic signature by the immune system.
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Affiliation(s)
- Hui Jing Lim
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute of Infection and Immunity, Melbourne, Victoria, Australia
| | - Jacinta M. Wubben
- Infection and Immunity Program and The Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, Clayton, Victoria, Australia
| | - Cristian Pinero Garcia
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, The University of New South Wales, Sydney, Australia
| | - Sebastian Cruz-Gomez
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute of Infection and Immunity, Melbourne, Victoria, Australia
| | - Jieru Deng
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute of Infection and Immunity, Melbourne, Victoria, Australia
| | - Jeffrey Y.W. Mak
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Abderrahman Hachani
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute of Infection and Immunity, Melbourne, Victoria, Australia
| | - Regan J. Anderson
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand
| | - Gavin F. Painter
- Ferrier Research Institute, Victoria University of Wellington, Wellington, New Zealand
| | - Jesse Goyette
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, The University of New South Wales, Sydney, Australia
| | - Shanika L. Amarasinghe
- Epigenetics and Development Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Matthew E. Ritchie
- Epigenetics and Development Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Antoine Roquilly
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute of Infection and Immunity, Melbourne, Victoria, Australia
- Nantes Université, CHU Nantes, INSERM, Center for Research in Transplantation and Translational Immunology, UMR 1064; F-44000, Nantes, France
| | - David P. Fairlie
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Katharina Gaus
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, The University of New South Wales, Sydney, Australia
| | - Jamie Rossjohn
- Infection and Immunity Program and The Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute Monash University, Clayton, Victoria, Australia
- Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, UK
| | - Jose A. Villadangos
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute of Infection and Immunity, Melbourne, Victoria, Australia
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
- Jose A. Villadangos:
| | - Hamish E.G. McWilliam
- Department of Microbiology and Immunology, The University of Melbourne, The Peter Doherty Institute of Infection and Immunity, Melbourne, Victoria, Australia
- Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
- Correspondence to Hamish E.G. McWilliam:
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Browning AP, Ansari N, Drovandi C, Johnston APR, Simpson MJ, Jenner AL. Identifying cell-to-cell variability in internalization using flow cytometry. J R Soc Interface 2022; 19:20220019. [PMID: 35611619 PMCID: PMC9131125 DOI: 10.1098/rsif.2022.0019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Biological heterogeneity is a primary contributor to the variation observed in experiments that probe dynamical processes, such as the internalization of material by cells. Given that internalization is a critical process by which many therapeutics and viruses reach their intracellular site of action, quantifying cell-to-cell variability in internalization is of high biological interest. Yet, it is common for studies of internalization to neglect cell-to-cell variability. We develop a simple mathematical model of internalization that captures the dynamical behaviour, cell-to-cell variation, and extrinsic noise introduced by flow cytometry. We calibrate our model through a novel distribution-matching approximate Bayesian computation algorithm to flow cytometry data of internalization of anti-transferrin receptor antibody in a human B-cell lymphoblastoid cell line. This approach provides information relating to the region of the parameter space, and consequentially the nature of cell-to-cell variability, that produces model realizations consistent with the experimental data. Given that our approach is agnostic to sample size and signal-to-noise ratio, our modelling framework is broadly applicable to identify biological variability in single-cell data from internalization assays and similar experiments that probe cellular dynamical processes.
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Affiliation(s)
- Alexander P Browning
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia.,ARC Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, Brisbane, Australia.,QUT Centre for Data Science, Queensland University of Technology, Brisbane, Australia
| | - Niloufar Ansari
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 399 Royal Parade, Parkville, Victoria 3052, Australia
| | - Christopher Drovandi
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia.,ARC Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, Brisbane, Australia.,QUT Centre for Data Science, Queensland University of Technology, Brisbane, Australia
| | - Angus P R Johnston
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 399 Royal Parade, Parkville, Victoria 3052, Australia
| | - Matthew J Simpson
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia.,QUT Centre for Data Science, Queensland University of Technology, Brisbane, Australia
| | - Adrianne L Jenner
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia.,QUT Centre for Data Science, Queensland University of Technology, Brisbane, Australia
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Nagamachi A, Kanai A, Nakamura M, Okuda H, Yokoyama A, Shinriki S, Matsui H, Inaba T. Multiorgan failure with abnormal receptor metabolism in mice mimicking Samd9/9L syndromes. J Clin Invest 2021; 131:140147. [PMID: 33373325 DOI: 10.1172/jci140147] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 12/10/2020] [Indexed: 12/17/2022] Open
Abstract
Autosomal dominant sterile α motif domain containing 9 (Samd9) and Samd9L (Samd9/9L) syndromes are a large subgroup of currently established inherited bone marrow failure syndromes that includes myelodysplasia, infection, growth restriction, adrenal hypoplasia, genital phenotypes, and enteropathy (MIRAGE), ataxia pancytopenia, and familial monosomy 7 syndromes. Samd9/9L genes are located in tandem on chromosome 7 and have been known to be the genes responsible for myeloid malignancies associated with monosomy 7. Additionally, as IFN-inducible genes, Samd9/9L are crucial for protection against viruses. Samd9/9L syndromes are caused by gain-of-function mutations and develop into infantile myelodysplastic syndromes associated with monosomy 7 (MDS/-7) at extraordinarily high frequencies. We generated mice expressing Samd9LD764N, which mimic MIRAGE syndrome, presenting with growth retardation, a short life, bone marrow failure, and multiorgan degeneration. In hematopoietic cells, Samd9LD764N downregulates the endocytosis of transferrin and c-Kit, resulting in a rare cause of anemia and a low bone marrow reconstitutive potential that ultimately causes MDS/-7. In contrast, in nonhematopoietic cells we tested, Samd9LD764N upregulated the endocytosis of EGFR by Ship2 phosphatase translocation to the cytomembrane and activated lysosomes, resulting in the reduced expression of surface receptors and signaling. Thus, Samd9/9L is a downstream regulator of IFN that controls receptor metabolism, with constitutive activation leading to multiorgan dysfunction.
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Affiliation(s)
- Akiko Nagamachi
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Akinori Kanai
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Megumi Nakamura
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Hiroshi Okuda
- Tsuruoka Metabolomics Laboratory, National Cancer Center, Tsuruoka, Yamagata, Japan
| | - Akihiko Yokoyama
- Tsuruoka Metabolomics Laboratory, National Cancer Center, Tsuruoka, Yamagata, Japan.,National Cancer Center Research Institute, Tokyo, Japan
| | - Satoru Shinriki
- Department of Molecular Laboratory Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Hirotaka Matsui
- Department of Molecular Laboratory Medicine, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Toshiya Inaba
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
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5
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FitzGerald LI, Johnston AP. It’s what’s on the inside that counts: Techniques for investigating the uptake and recycling of nanoparticles and proteins in cells. J Colloid Interface Sci 2021; 587:64-78. [DOI: 10.1016/j.jcis.2020.11.076] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 09/15/2020] [Accepted: 11/23/2020] [Indexed: 01/19/2023]
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6
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Cevaal PM, Ali A, Czuba-Wojnilowicz E, Symons J, Lewin SR, Cortez-Jugo C, Caruso F. In Vivo T Cell-Targeting Nanoparticle Drug Delivery Systems: Considerations for Rational Design. ACS NANO 2021; 15:3736-3753. [PMID: 33600163 DOI: 10.1021/acsnano.0c09514] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
T cells play an important role in immunity and repair and are implicated in diseases, including blood cancers, viral infections, and inflammation, making them attractive targets for the treatment and prevention of diseases. Over recent years, the advent of nanomedicine has shown an increase in studies that use nanoparticles as carriers to deliver therapeutic cargo to T cells for ex vivo and in vivo applications. Nanoparticle-based delivery has several advantages, including the ability to load and protect a variety of drugs, control drug release, improve drug pharmacokinetics and biodistribution, and site- or cell-specific targeting. However, the delivery of nanoparticles to T cells remains a major technological challenge, which is primarily due to the nonphagocytic nature of T cells. In this review, we discuss the physiological barriers to effective T cell targeting and describe the different approaches used to deliver cargo-loaded nanoparticles to T cells for the treatment of disease such as T cell lymphoma and human immunodeficiency virus (HIV). In particular, engineering strategies that aim to improve nanoparticle internalization by T cells, including ligand-based targeting, will be highlighted. These nanoparticle engineering approaches are expected to inspire the development of effective nanomaterials that can target or manipulate the function of T cells for the treatment of T cell-related diseases.
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Affiliation(s)
| | | | - Ewa Czuba-Wojnilowicz
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | | | - Sharon R Lewin
- Victorian Infectious Diseases, Royal Melbourne Hospital at The Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria 3000, Australia
- Department of Infectious Diseases, Alfred Hospital and Monash University, Melbourne, Victoria 3004, Australia
| | - Christina Cortez-Jugo
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Frank Caruso
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
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7
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A molecular sensor to quantify the localization of proteins, DNA and nanoparticles in cells. Nat Commun 2020; 11:4482. [PMID: 32901011 PMCID: PMC7479595 DOI: 10.1038/s41467-020-18082-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 07/28/2020] [Indexed: 12/22/2022] Open
Abstract
Intracellular trafficking governs receptor signaling, pathogenesis, immune responses and fate of nanomedicines. These processes are typically tracked by observing colocalization of fluorescent markers using confocal microscopy. However, this method is low throughput, limited by the resolution of microscopy, and can miss fleeting interactions. To address this, we developed a localization sensor composed of a quenched SNAP-tag substrate (SNAPSwitch) that can be conjugated to biomolecules using click chemistry. SNAPSwitch enables quantitative detection of trafficking to locations of interest within live cells using flow cytometry. Using SNAPSwitch, we followed the trafficking of DNA complexes from endosomes into the cytosol and nucleus. We show that antibodies against the transferrin or hyaluronan receptor are initially sorted into different compartments following endocytosis. In addition, we can resolve which side of the cellular membrane material was located. These results demonstrate SNAPSwitch is a high-throughput and broadly applicable tool to quantitatively track localization of materials in cells. Determining the trafficking of intracellular material is commonly done by colocalisation analysis using microscopy. Here the authors monitor trafficking of select cargo by measuring the conversion of quenched SNAP-tag substrates by subcellularly-localised SNAP-tag and detection by flow cytometry.
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8
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Montealegre S, Abramova A, Manceau V, de Kanter AF, van Endert P. The role of MHC class I recycling and Arf6 in cross-presentation by murine dendritic cells. Life Sci Alliance 2019; 2:2/6/e201900464. [PMID: 31740564 PMCID: PMC6861705 DOI: 10.26508/lsa.201900464] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 11/01/2019] [Accepted: 11/04/2019] [Indexed: 11/24/2022] Open
Abstract
Cross-presentation by MHC class I molecules (MHC-I) is critical for priming of cytotoxic T cells. Peptides derived from cross-presented antigens can be loaded on MHC-I in the endoplasmic reticulum and in endocytic or phagocytic compartments of murine DCs. However, the origin of MHC-I in the latter compartments is poorly understood. Recently, Rab22-dependent MHC-I recycling through a Rab11+ compartment has been suggested to be implicated in cross-presentation. We have examined the existence of MHC-I recycling and the role of Arf6, described to regulate recycling in nonprofessional antigen presenting cells, in murine DCs. We confirm folded MHC-I accumulation in a juxtanuclear Rab11+ compartment and partially localize Arf6 to this compartment. MHC-I undergo fast recycling, however, both folded and unfolded internalized MHC-I fail to recycle to the Rab11+Arf6+ compartment. Therefore, the source of MHC-I molecules in DC endocytic compartments remains to be identified. Functionally, depletion of Arf6 compromises cross-presentation of immune complexes but not of soluble, phagocytosed or mannose receptor-targeted antigen, suggesting a role of Fc receptor-regulated Arf6 trafficking in cross-presentation of immune complexes.
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Affiliation(s)
- Sebastian Montealegre
- Institut National de la Santé et de la Recherche Médicale, Unité 1151, Paris, France.,Université Paris Descartes, Faculté de Médecine, Paris, France.,Centre National de la Recherche Scientifique, UMR8253, Paris, France
| | - Anastasia Abramova
- Institut National de la Santé et de la Recherche Médicale, Unité 1151, Paris, France.,Université Paris Descartes, Faculté de Médecine, Paris, France.,Centre National de la Recherche Scientifique, UMR8253, Paris, France
| | - Valerie Manceau
- Institut National de la Santé et de la Recherche Médicale, Unité 1151, Paris, France.,Université Paris Descartes, Faculté de Médecine, Paris, France.,Centre National de la Recherche Scientifique, UMR8253, Paris, France
| | - Anne-Floor de Kanter
- Institut National de la Santé et de la Recherche Médicale, Unité 1151, Paris, France.,Université Paris Descartes, Faculté de Médecine, Paris, France.,Centre National de la Recherche Scientifique, UMR8253, Paris, France
| | - Peter van Endert
- Institut National de la Santé et de la Recherche Médicale, Unité 1151, Paris, France .,Université Paris Descartes, Faculté de Médecine, Paris, France.,Centre National de la Recherche Scientifique, UMR8253, Paris, France
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9
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Nagamachi A, Kikuchi J, Kanai A, Furukawa Y, Inaba T. Kinetics of cytokine receptor internalization under steady-state conditions affects growth of neighboring blood cells. Haematologica 2019; 105:e325-e327. [PMID: 31672901 DOI: 10.3324/haematol.2019.232959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Akiko Nagamachi
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology & Medicine, Hiroshima University, Minami-ku, Hiroshima
| | - Jiro Kikuchi
- Division of Stem Cell Regulation, Center for Molecular Medicine, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, Japan
| | - Akinori Kanai
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology & Medicine, Hiroshima University, Minami-ku, Hiroshima
| | - Yusuke Furukawa
- Division of Stem Cell Regulation, Center for Molecular Medicine, Jichi Medical University, Yakushiji, Shimotsuke, Tochigi, Japan
| | - Toshiya Inaba
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology & Medicine, Hiroshima University, Minami-ku, Hiroshima
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Selby LI, Aurelio L, Yuen D, Graham B, Johnston APR. Quantifying Cellular Internalization with a Fluorescent Click Sensor. ACS Sens 2018; 3:1182-1189. [PMID: 29676153 DOI: 10.1021/acssensors.8b00219] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability to determine the amount of material endocytosed by a cell is important for our understanding of cell biology and in the design of effective carriers for drug delivery. To quantify internalization by fluorescence, the signal from material remaining on the cell surface must be differentiated from endocytosed material. Sensors for internalization offer advantages over traditional methods for achieving this as they exhibit improved sensitivity, allow for multiple fluorescent markers to be used simultaneously, and are amenable to high-throughput analysis. We have developed a small fluorescent internalization sensor, similar in size to a standard fluorescent dye, that can be conjugated to proteins and uses the rapid and highly specific bio-orthogonal reaction between a tetrazine and a trans-cyclooctene group to switch off the surface signal. The sensor can be attached to a variety of materials using simple chemistry and is compatible with flow cytometry and fluorescence microscopy, making it a useful tool to study the uptake of material into cells.
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Affiliation(s)
- Laura I. Selby
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia
| | - Luigi Aurelio
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Daniel Yuen
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Bim Graham
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Angus P. R. Johnston
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash University, Parkville, Victoria 3052, Australia
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