1
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Chowdhury R, Mimoso T, Chouaib AA, Mougios N, Krah D, Opazo F, Köster S, Rizzoli SO, Shaib AH. Microtubules as a versatile reference standard for expansion microscopy. Commun Biol 2025; 8:499. [PMID: 40140540 PMCID: PMC11947214 DOI: 10.1038/s42003-025-07967-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2024] [Accepted: 03/19/2025] [Indexed: 03/28/2025] Open
Abstract
Expansion microscopy (ExM) is continually improving, and new ExM variants need to be validated on well-defined biological structures. There is no consensus on validation structures for ExM, especially as nuclear pore complexes or DNA nanorulers are not popular for ExM studies. Here we propose that microtubules should be used for ExM validation. The diameter of microtubules immunostained using primary and secondary antibodies is sufficiently large for the validation of techniques with resolutions better than 50 nm. For techniques with higher precision (up to ~10 nm), microtubules can be assembled and imaged in vitro, using a protocol that we introduce here. Alternatively, a cellular extraction procedure can be employed, followed by labeling the peptide chains of the tubulin molecules with NHS-ester fluorophores. Finally, for nanometer-scale techniques, single tubulin molecules can be analyzed. We conclude that microtubules are valuable structures for the validation of ExM and related technologies.
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Affiliation(s)
- Rajdeep Chowdhury
- Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany
- Department of Chemistry, GITAM School of Science, GITAM, Hyderabad, Telangana, India
| | - Tiago Mimoso
- Institute for X-Ray Physics, University of Göttingen, Göttingen, Germany
| | - Abed Alrahman Chouaib
- Department of Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany
| | - Nikolaos Mougios
- Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
| | - Donatus Krah
- Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany
| | - Felipe Opazo
- Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
- NanoTag Biotechnologies GmbH, Göttingen, Germany
| | - Sarah Köster
- Institute for X-Ray Physics, University of Göttingen, Göttingen, Germany.
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany.
| | - Silvio O Rizzoli
- Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany.
- Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany.
- Cluster of Excellence "Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany.
| | - Ali H Shaib
- Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany.
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2
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Langner E, Puapatanakul P, Pudlowski R, Alsabbagh DY, Miner JH, Horani A, Dutcher SK, Brody SL, Wang JT, Suleiman HY, Mahjoub MR. Ultrastructure expansion microscopy (U-ExM) of mouse and human kidneys for analysis of subcellular structures. Cytoskeleton (Hoboken) 2024; 81:618-638. [PMID: 38715433 PMCID: PMC11540979 DOI: 10.1002/cm.21870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/11/2024] [Accepted: 04/22/2024] [Indexed: 05/21/2024]
Abstract
Ultrastructure expansion microscopy (U-ExM) involves the physical magnification of specimens embedded in hydrogels, which allows for super-resolution imaging of subcellular structures using a conventional diffraction-limited microscope. Methods for expansion microscopy exist for several organisms, organs, and cell types, and used to analyze cellular organelles and substructures in nanoscale resolution. Here, we describe a simple step-by-step U-ExM protocol for the expansion, immunostaining, imaging, and analysis of cytoskeletal and organellar structures in kidney tissue. We detail the critical modified steps to optimize isotropic kidney tissue expansion, and preservation of the renal cell structures of interest. We demonstrate the utility of the approach using several markers of renal cell types, centrioles, cilia, the extracellular matrix, and other cytoskeletal elements. Finally, we show that the approach works well on mouse and human kidney samples that were preserved using different fixation and embedding conditions. Overall, this protocol provides a simple and cost-effective approach to analyze both preclinical and clinical renal samples in high detail, using conventional lab supplies and standard widefield or confocal microscopy.
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Affiliation(s)
- Ewa Langner
- Department of Medicine, Washington University, St. Louis, Missouri, USA
| | - Pongpratch Puapatanakul
- Department of Medicine, Washington University, St. Louis, Missouri, USA
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Rachel Pudlowski
- Department of Biology, Washington University, St. Louis, Missouri, USA
| | | | - Jeffrey H Miner
- Department of Medicine, Washington University, St. Louis, Missouri, USA
| | - Amjad Horani
- Department of Pediatrics, Washington University, St. Louis, Missouri, USA
| | - Susan K Dutcher
- Department of Genetics, Washington University, St. Louis, Missouri, USA
| | - Steven L Brody
- Department of Medicine, Washington University, St. Louis, Missouri, USA
| | - Jennifer T Wang
- Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Hani Y Suleiman
- Department of Medicine, Washington University, St. Louis, Missouri, USA
| | - Moe R Mahjoub
- Department of Medicine, Washington University, St. Louis, Missouri, USA
- Department of Cell Biology and Physiology, Washington University, St. Louis, Missouri, USA
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3
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Pesce L, Ricci P, Sportelli G, Belcari N, Sancataldo G. Expansion and Light-Sheet Microscopy for Nanoscale 3D Imaging. SMALL METHODS 2024; 8:e2301715. [PMID: 38461540 DOI: 10.1002/smtd.202301715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 02/10/2024] [Indexed: 03/12/2024]
Abstract
Expansion Microscopy (ExM) and Light-Sheet Fluorescence Microscopy (LSFM) are forefront imaging techniques that enable high-resolution visualization of biological specimens. ExM enhances nanoscale investigation using conventional fluorescence microscopes, while LSFM offers rapid, minimally invasive imaging over large volumes. This review explores the joint advancements of ExM and LSFM, focusing on the excellent performance of the integrated modality obtained from the combination of the two, which is refer to as ExLSFM. In doing so, the chemical processes required for ExM, the tailored optical setup of LSFM for examining expanded samples, and the adjustments in sample preparation for accurate data collection are emphasized. It is delve into various specimen types studied using this integrated method and assess its potential for future applications. The goal of this literature review is to enrich the comprehension of ExM and LSFM, encouraging their wider use and ongoing development, looking forward to the upcoming challenges, and anticipating innovations in these imaging techniques.
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Affiliation(s)
- Luca Pesce
- Department of Physics - Enrico Fermi, University of Pisa, Largo Pontecorvo, 3, Pisa, 56127, Italy
| | - Pietro Ricci
- Department of Applied Physics, University of Barcelona, C/Martí i Franquès, 1, Barcelona, 08028, Spain
| | - Giancarlo Sportelli
- Department of Physics - Enrico Fermi, University of Pisa, Largo Pontecorvo, 3, Pisa, 56127, Italy
| | - Nicola Belcari
- Department of Physics - Enrico Fermi, University of Pisa, Largo Pontecorvo, 3, Pisa, 56127, Italy
| | - Giuseppe Sancataldo
- Department of Physics - Emilio Segrè, University of Palermo, Viale delle Scienze, 18, Palermo, 90128, Italy
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4
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Hümpfer N, Thielhorn R, Ewers H. Expanding boundaries - a cell biologist's guide to expansion microscopy. J Cell Sci 2024; 137:jcs260765. [PMID: 38629499 PMCID: PMC11058692 DOI: 10.1242/jcs.260765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024] Open
Abstract
Expansion microscopy (ExM) is a revolutionary novel approach to increase resolution in light microscopy. In contrast to super-resolution microscopy methods that rely on sophisticated technological advances, including novel instrumentation, ExM instead is entirely based on sample preparation. In ExM, labeled target molecules in fixed cells are anchored in a hydrogel, which is then physically enlarged by osmotic swelling. The isotropic swelling of the hydrogel pulls the labels apart from one another, and their relative organization can thus be resolved using conventional microscopes even if it was below the diffraction limit of light beforehand. As ExM can additionally benefit from the technical resolution enhancements achieved by super-resolution microscopy, it can reach into the nanometer range of resolution with an astoundingly low degree of error induced by distortion during the physical expansion process. Because the underlying chemistry is well understood and the technique is based on a relatively simple procedure, ExM is easily reproducible in non-expert laboratories and has quickly been adopted to address an ever-expanding spectrum of problems across the life sciences. In this Review, we provide an overview of this rapidly expanding new field, summarize the most important insights gained so far and attempt to offer an outlook on future developments.
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Affiliation(s)
- Nadja Hümpfer
- Department of Biology, Chemistry and Pharmacy, Institut für Chemie und Biochemie, Freie Universität Berlin, 14195 Berlin, Germany
| | - Ria Thielhorn
- Department of Biology, Chemistry and Pharmacy, Institut für Chemie und Biochemie, Freie Universität Berlin, 14195 Berlin, Germany
| | - Helge Ewers
- Department of Biology, Chemistry and Pharmacy, Institut für Chemie und Biochemie, Freie Universität Berlin, 14195 Berlin, Germany
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5
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Langner E, Puapatanakul P, Pudlowski R, Alsabbagh DY, Miner JH, Horani A, Dutcher SK, Brody SL, Wang JT, Suleiman HY, Mahjoub MR. Ultrastructure expansion microscopy (U-ExM) of mouse and human kidneys for analysis of subcellular structures. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.16.580708. [PMID: 38405695 PMCID: PMC10889020 DOI: 10.1101/2024.02.16.580708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Ultrastructure expansion microscopy (U-ExM) involves the physical magnification of specimens embedded in hydrogels, which allows for super-resolution imaging of subcellular structures using a conventional diffraction-limited microscope. Methods for expansion microscopy exist for several organisms, organs, and cell types, and used to analyze cellular organelles and substructures in nanoscale resolution. Here, we describe a simple step-by-step U-ExM protocol for the expansion, immunostaining, imaging, and analysis of cytoskeletal and organellar structures in kidney tissue. We detail the critical modified steps to optimize isotropic kidney tissue expansion, and preservation of the renal cell structures of interest. We demonstrate the utility of the approach using several markers of renal cell types, centrioles, cilia, the extracellular matrix, and other cytoskeletal elements. Finally, we show that the approach works well on mouse and human kidney samples that were preserved using different fixation and storage conditions. Overall, this protocol provides a simple and cost-effective approach to analyze both pre-clinical and clinical renal samples in high detail, using conventional lab supplies and standard widefield or confocal microscopy.
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6
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Theiss M, Hériché JK, Russell C, Helekal D, Soppitt A, Ries J, Ellenberg J, Brazma A, Uhlmann V. Simulating structurally variable nuclear pore complexes for microscopy. Bioinformatics 2023; 39:btad587. [PMID: 37756700 PMCID: PMC10570993 DOI: 10.1093/bioinformatics/btad587] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 09/08/2023] [Accepted: 09/22/2023] [Indexed: 09/29/2023] Open
Abstract
MOTIVATION The nuclear pore complex (NPC) is the only passageway for macromolecules between nucleus and cytoplasm, and an important reference standard in microscopy: it is massive and stereotypically arranged. The average architecture of NPC proteins has been resolved with pseudoatomic precision, however observed NPC heterogeneities evidence a high degree of divergence from this average. Single-molecule localization microscopy (SMLM) images NPCs at protein-level resolution, whereupon image analysis software studies NPC variability. However, the true picture of this variability is unknown. In quantitative image analysis experiments, it is thus difficult to distinguish intrinsically high SMLM noise from variability of the underlying structure. RESULTS We introduce CIR4MICS ('ceramics', Configurable, Irregular Rings FOR MICroscopy Simulations), a pipeline that synthesizes ground truth datasets of structurally variable NPCs based on architectural models of the true NPC. Users can select one or more N- or C-terminally tagged NPC proteins, and simulate a wide range of geometric variations. We also represent the NPC as a spring-model such that arbitrary deforming forces, of user-defined magnitudes, simulate irregularly shaped variations. Further, we provide annotated reference datasets of simulated human NPCs, which facilitate a side-by-side comparison with real data. To demonstrate, we synthetically replicate a geometric analysis of real NPC radii and reveal that a range of simulated variability parameters can lead to observed results. Our simulator is therefore valuable to test the capabilities of image analysis methods, as well as to inform experimentalists about the requirements of hypothesis-driven imaging studies. AVAILABILITY AND IMPLEMENTATION Code: https://github.com/uhlmanngroup/cir4mics. Simulated data: BioStudies S-BSST1058.
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Affiliation(s)
- Maria Theiss
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, CB10 1SD, United Kingdom
| | - Jean-Karim Hériché
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg 69117, Germany
| | - Craig Russell
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, CB10 1SD, United Kingdom
| | - David Helekal
- Centre for Doctoral Training in Mathematics for Real-World Systems, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Alisdair Soppitt
- EPSRC Centre for Doctoral Training in Modelling of Heterogeneous Systems, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Jonas Ries
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg 69117, Germany
- Max Perutz Labs, University of Vienna, Department of Structural and Computational Biology, Dr.-Bohr-Gasse 9, Vienna 1030, Austria
| | - Jan Ellenberg
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg 69117, Germany
| | - Alvis Brazma
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, CB10 1SD, United Kingdom
| | - Virginie Uhlmann
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, CB10 1SD, United Kingdom
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7
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Wen G, Leen V, Rohand T, Sauer M, Hofkens J. Current Progress in Expansion Microscopy: Chemical Strategies and Applications. Chem Rev 2023; 123:3299-3323. [PMID: 36881995 DOI: 10.1021/acs.chemrev.2c00711] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
Expansion microscopy (ExM) is a newly developed super-resolution technique, allowing visualization of biological targets at nanoscale resolution on conventional fluorescence microscopes. Since its introduction in 2015, many efforts have been dedicated to broaden its application range or increase the resolution that can be achieved. As a consequence, recent years have witnessed remarkable advances in ExM. This review summarizes recent progress in ExM, with the focus on the chemical aspects of the method, from chemistries for biomolecule grafting to polymer synthesis and the impact on biological analysis. The combination of ExM with other microscopy techniques, in search of additional resolution improvement, is also discussed. In addition, we compare pre- and postexpansion labeling strategies and discuss the impact of fixation methods on ultrastructure preservation. We conclude this review with a perspective on existing challenges and future directions. We believe that this review will provide a comprehensive understanding of ExM and facilitate its usage and further development.
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Affiliation(s)
- Gang Wen
- Department of Chemistry, KU Leuven, Leuven 3001, Belgium
| | - Volker Leen
- Chrometra Scientific, Kortenaken 3470, Belgium
| | - Taoufik Rohand
- Laboratory of Analytical and Molecular Chemistry, Faculty Polydisciplinaire of Safi, University Cadi Ayyad Marrakech, BP 4162, 46000 Safi, Morocco
| | - Markus Sauer
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Johan Hofkens
- Department of Chemistry, KU Leuven, Leuven 3001, Belgium
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany
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8
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Hawkins TJ, Robson JL, Cole B, Bush SJ. Expansion Microscopy of Plant Cells (PlantExM). Methods Mol Biol 2023; 2604:127-142. [PMID: 36773230 DOI: 10.1007/978-1-0716-2867-6_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Expansion microscopy (ExM) achieves super-resolution imaging without the need for sophisticated super-resolution microscopy hardware through a combination of physical and optical magnification. Samples are fixed, stained, and embedded in a swellable gel. Following cross-linking of fluorophores to the gel matrix, the components of the sample are digested away and the gel expanded in water. Labeled objects which are too close to be resolved by diffraction-limited microscopy are moved far enough apart that these can now be resolved as individual objects on a standard confocal. Originally developed for animal cells and tissues, ExM for plants requires the additional consideration of cell wall digestion. Super-resolution can be limited in plants due to the size of cells, light scattering of tissues, and variations in refractive index. By removing the components which cause these limitations, ExM opens up the possibility of super-resolution at depth within plant tissues for the first time. Here we describe our method for PlantExM which is optimized for cytoskeleton resolution, which, when also coupled with compatible optical super-resolution technologies, can produce images of the plant cytoskeleton in unprecedented detail.
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Affiliation(s)
| | | | - Bethany Cole
- Department of Biosciences, Durham University, Durham, UK
| | - Simon J Bush
- Department of Biosciences, Durham University, Durham, UK
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9
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Affiliation(s)
- Sven Truckenbrodt
- Convergent Research, E11 Bio. 1600 Harbor Bay Parkway, Alameda, California94502, United States
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10
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Capitini C, Pesce L, Fani G, Mazzamuto G, Genovese M, Franceschini A, Paoli P, Pieraccini G, Zasloff M, Chiti F, Pavone FS, Calamai M. Studying the trafficking of labeled trodusquemine and its application as nerve marker for light-sheet and expansion microscopy. FASEB J 2022; 36:e22655. [PMID: 36421008 PMCID: PMC9827910 DOI: 10.1096/fj.202201276r] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 10/27/2022] [Accepted: 11/01/2022] [Indexed: 11/25/2022]
Abstract
Trodusquemine is an aminosterol with a variety of biological and pharmacological functions, such as acting as an antimicrobial, stimulating body weight loss and interfering with the toxicity of proteins involved in the development of Alzheimer's and Parkinson's diseases. The mechanisms of interaction of aminosterols with cells are, however, still largely uncharacterized. Here, by using fluorescently labeled trodusquemine (TRO-A594 and TRO-ATTO565), we show that trodusquemine binds initially to the plasma membrane of living cells, that the binding affinity is dependent on cholesterol, and that trodusquemine is then internalized and mainly targeted to lysosomes after internalization. We also found that TRO-A594 is able to strongly and selectively bind to myelinated fibers in fixed mouse brain slices, and that it is a marker compatible with tissue clearing and light-sheet fluorescence microscopy or expansion microscopy. In conclusion, this work contributes to further characterize the biology of aminosterols and provides a new tool for nerve labeling suitable for the most advanced microscopy techniques.
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Affiliation(s)
- Claudia Capitini
- European Laboratory for Non‐Linear Spectroscopy (LENS)University of FlorenceSesto FiorentinoItaly,Department of PhysicsUniversity of FlorenceSesto FiorentinoItaly
| | - Luca Pesce
- European Laboratory for Non‐Linear Spectroscopy (LENS)University of FlorenceSesto FiorentinoItaly,Department of PhysicsUniversity of FlorenceSesto FiorentinoItaly
| | - Giulia Fani
- Department of Experimental and Clinical Biomedical Sciences, Section of BiochemistryUniversity of FlorenceFlorenceItaly
| | - Giacomo Mazzamuto
- European Laboratory for Non‐Linear Spectroscopy (LENS)University of FlorenceSesto FiorentinoItaly,Department of PhysicsUniversity of FlorenceSesto FiorentinoItaly,National Institute of Optics – National Research Council (CNR‐INO)Sesto FiorentinoItaly
| | - Massimo Genovese
- Department of Experimental and Clinical Biomedical Sciences, Section of BiochemistryUniversity of FlorenceFlorenceItaly
| | - Alessandra Franceschini
- European Laboratory for Non‐Linear Spectroscopy (LENS)University of FlorenceSesto FiorentinoItaly,Department of PhysicsUniversity of FlorenceSesto FiorentinoItaly
| | - Paolo Paoli
- Department of Experimental and Clinical Biomedical Sciences, Section of BiochemistryUniversity of FlorenceFlorenceItaly
| | | | - Michael Zasloff
- Enterin Inc.PhiladelphiaPennsylvaniaUSA,MedStar‐Georgetown Transplant InstituteGeorgetown University School of MedicineWashingtonDCUSA
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences, Section of BiochemistryUniversity of FlorenceFlorenceItaly
| | - Francesco S. Pavone
- European Laboratory for Non‐Linear Spectroscopy (LENS)University of FlorenceSesto FiorentinoItaly,Department of PhysicsUniversity of FlorenceSesto FiorentinoItaly,National Institute of Optics – National Research Council (CNR‐INO)Sesto FiorentinoItaly
| | - Martino Calamai
- European Laboratory for Non‐Linear Spectroscopy (LENS)University of FlorenceSesto FiorentinoItaly,National Institute of Optics – National Research Council (CNR‐INO)Sesto FiorentinoItaly
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11
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Faulkner EL, Pike JA, Densham RM, Garlick E, Thomas SG, Neely RK, Morris JR. Imaging nanoscale nuclear structures with expansion microscopy. J Cell Sci 2022; 135:276027. [PMID: 35748225 PMCID: PMC9450888 DOI: 10.1242/jcs.259009] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 06/21/2022] [Indexed: 11/20/2022] Open
Abstract
Commonly applied super-resolution light microscopies have provided insight into subcellular processes at the nanoscale. However, imaging depth, speed, throughput and cost remain significant challenges, limiting the numbers of three-dimensional (3D) nanoscale processes that can be investigated and the number of laboratories able to undertake such analysis. Expansion microscopy (ExM) solves many of these limitations, but its application to imaging nuclear processes has been constrained by concerns of unequal nuclear expansion. Here, we demonstrate the conditions for isotropic expansion of the nucleus at a resolution equal to or better than 120–130 nm (pre-expansion). Using the DNA damage response proteins BRCA1, 53BP1 (also known as TP53BP1) and RAD51 as exemplars, we quantitatively describe the 3D nanoscale organisation of over 50,000 DNA damage response structures. We demonstrate the ability to assess chromatin-regulated events and show the simultaneous assessment of four elements. This study thus demonstrates how ExM can contribute to the investigation of nanoscale nuclear processes. Summary: Expansion microscopy provides quantitative insight into the impact of chromatin modifiers on spatiotemporal organisation of the DNA repair proteins BRCA1, 53BP1 and RAD51 at a resolution of 65–70 nm.
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Affiliation(s)
- Emma L Faulkner
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.,Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Jeremy A Pike
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.,COMPARE, University of Birmingham and University of Nottingham, Midlands, UK
| | - Ruth M Densham
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, B15 2TT, UK
| | - Evelyn Garlick
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.,COMPARE, University of Birmingham and University of Nottingham, Midlands, UK
| | - Steven G Thomas
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.,COMPARE, University of Birmingham and University of Nottingham, Midlands, UK
| | - Robert K Neely
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Joanna R Morris
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, B15 2TT, UK
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12
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Pesce L, Scardigli M, Gavryusev V, Laurino A, Mazzamuto G, Brady N, Sancataldo G, Silvestri L, Destrieux C, Hof PR, Costantini I, Pavone FS. 3D molecular phenotyping of cleared human brain tissues with light-sheet fluorescence microscopy. Commun Biol 2022; 5:447. [PMID: 35551498 PMCID: PMC9098858 DOI: 10.1038/s42003-022-03390-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 04/21/2022] [Indexed: 12/17/2022] Open
Abstract
The combination of optical tissue transparency with immunofluorescence allows the molecular characterization of biological tissues in 3D. However, adult human organs are particularly challenging to become transparent because of the autofluorescence contributions of aged tissues. To meet this challenge, we optimized SHORT (SWITCH-H2O2-antigen Retrieval-TDE), a procedure based on standard histological treatments in combination with a refined clearing procedure to clear and label portions of the human brain. 3D histological characterization with multiple molecules is performed on cleared samples with a combination of multi-colors and multi-rounds labeling. By performing fast 3D imaging of the samples with a custom-made inverted light-sheet fluorescence microscope (LSFM), we reveal fine details of intact human brain slabs at subcellular resolution. Overall, we proposed a scalable and versatile technology that in combination with LSFM allows mapping the cellular and molecular architecture of the human brain, paving the way to reconstruct the entire organ.
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Affiliation(s)
- Luca Pesce
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, Sesto Fiorentino, Italy
| | - Marina Scardigli
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, Sesto Fiorentino, Italy
| | - Vladislav Gavryusev
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, Sesto Fiorentino, Italy
| | - Annunziatina Laurino
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - Giacomo Mazzamuto
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- National Institute of Optics (INO), National Research Council (CNR), Sesto Fiorentino, Italy
| | - Niamh Brady
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
| | - Giuseppe Sancataldo
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
| | - Ludovico Silvestri
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, Sesto Fiorentino, Italy
- National Institute of Optics (INO), National Research Council (CNR), Sesto Fiorentino, Italy
| | | | - Patrick R Hof
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Irene Costantini
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy.
- National Institute of Optics (INO), National Research Council (CNR), Sesto Fiorentino, Italy.
- Department of Biology, University of Florence, Florence, Italy.
| | - Francesco S Pavone
- European Laboratory for Non-linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, Sesto Fiorentino, Italy
- National Institute of Optics (INO), National Research Council (CNR), Sesto Fiorentino, Italy
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13
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Li H, Warden AR, He J, Shen G, Ding X. Expansion microscopy with ninefold swelling (NIFS) hydrogel permits cellular ultrastructure imaging on conventional microscope. SCIENCE ADVANCES 2022; 8:eabm4006. [PMID: 35507653 PMCID: PMC9067917 DOI: 10.1126/sciadv.abm4006] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Superresolution microscopy enables probing of cellular ultrastructures. However, its widespread applications are limited by the need for expensive machinery, specific hardware, and sophisticated data processing. Expansion microscopy (ExM) improves the resolution of conventional microscopy by physically expanding biological specimens before imaging and currently provides ~70-nm resolution, which still lags behind that of modern superresolution microscopy (~30 nm). Here, we demonstrate a ninefold swelling (NIFS) hydrogel, that can reduce ExM resolution to 31 nm when using regular traditional microscopy. We also design a detachable chip that integrates all the experimental operations to facilitate the maximal reproducibility of this high-resolution imaging technology. We demonstrate this technique on the superimaging of nuclear pore complex and clathrin-coated pits, whose structures can hardly be resolved by conventional microscopy. The method presented here offers a universal platform with superresolution imaging to unveil cellular ultrastructural details using standard conventional laboratory microscopes.
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14
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Sun Y, Zhang Z, Bing T, Liu J, Li W, Liu X, Zhang N, Shu Y, Wang J, Shangguan D. Aptamer-Based Cell Nucleus Imaging via Expansion Microscopy. Anal Chem 2022; 94:6044-6049. [PMID: 35380789 DOI: 10.1021/acs.analchem.2c00773] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Expansion microscopy (ExM) is a newly developed technology in recent years that enables nanoscale imaging under conventional microscopes. Herein, we report an aptamer-based ExM imaging strategy. A nucleus-targeting aptamer Ch4-1 was chemically labeled with a dye and an acrydite at each end to perform the functions of molecular recognition, fluorescence reporting, and gel anchoring. After binding cell nucleus, the dual labeled aptamer Ac-Ch4-1-FAM directly participated in gelation and anchored in polyacrylamide gel. After expanding the gel, high-resolution imaging was achieved by confocal microscopy. Multicolor ExM imaging was also realized by combining Ac-Ch4-1-FAM, antibodies and fluorescent dyes. This aptamer-based ExM could clearly image the chromatin morphology at different mitotic stages. The expansion process is simple and the aptamer labeling is easy. The aptamer-based ExM holds great promise in super-resolution imaging of cells and tissues.
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Affiliation(s)
- Yue Sun
- Department of Chemistry, College of Sciences, Northeastern University, Shenyang 110819, China.,Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Zhicheng Zhang
- Department of Chemistry, College of Sciences, Northeastern University, Shenyang 110819, China.,Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Tao Bing
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jing Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weiwei Li
- The Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital), Institute of Basic Medicine and Cancer (IBMC), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China.,School of Molecular Medicine, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310013, China
| | - Xiangjun Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Nan Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yang Shu
- Department of Chemistry, College of Sciences, Northeastern University, Shenyang 110819, China
| | - Jianhua Wang
- Department of Chemistry, College of Sciences, Northeastern University, Shenyang 110819, China
| | - Dihua Shangguan
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,School of Molecular Medicine, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310013, China.,University of Chinese Academy of Sciences, Beijing 100049, China
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15
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Amodio A, Cassani M, Mummolo L, Cortez-Jugo C, Bhangu SK, Symons J, Ahlenstiel CL, Forte G, Ricci F, Kelleher AD, Lewin SR, Cavalieri F, Caruso F. Nanoscale probing and imaging of HIV-1 RNA in cells with a chimeric LNA-DNA sensor. NANOSCALE 2022; 14:3049-3061. [PMID: 35142755 DOI: 10.1039/d1nr08418f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Real-time detection and nanoscale imaging of human immunodeficiency virus type 1 ribonucleic acid (HIV-1 RNA) in latently infected cells that persist in people living with HIV-1 on antiretroviral therapy in blood and tissue may reveal new insights needed to cure HIV-1 infection. Herein, we develop a strategy combining DNA nanotechnology and super-resolution expansion microscopy (ExM) to detect and image a 22 base sequence transcribed from the HIV-1 promoter in model live and fixed cells. We engineer a chimeric locked nucleic acid (LNA)-DNA sensor via hybridization chain reaction to probe HIV-1 RNA in the U3 region of the HIV-1 long terminal repeat (LTR) by signal amplification in live cells. We find that the viral RNA transcript of the U3 region of the HIV-1 LTR, namely PromA, is a valid and specific biomarker to detect infected live cells. The efficiency and selectivity of the LNA-DNA sensor are evaluated in combination with ExM. Unlike standard ExM methods, which rely on additional custom linkers to anchor and immobilize RNA molecules in the intracellular polymeric network, in the current strategy, we probe and image the HIV-1 RNA target at nanoscale resolution, without resorting to chemical linkers or additional preparation steps. This is achieved by physical entrapment of the HIV-1 viral transcripts in the cells post-expansion by finely tuning the mesh size of the intracellular polymeric network.
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Affiliation(s)
- Alessia Amodio
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
- Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Marco Cassani
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
- International Clinical Research Center (ICRC), St Anne's University Hospital, CZ-65691 Brno, Czech Republic
| | - Liviana Mummolo
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
| | - Christina Cortez-Jugo
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
| | | | - Jori Symons
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria 3000, Australia
| | | | - Giancarlo Forte
- International Clinical Research Center (ICRC), St Anne's University Hospital, CZ-65691 Brno, Czech Republic
| | - Francesco Ricci
- Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Anthony D Kelleher
- Kirby Institute, University of New South Wales, New South Wales 2052, Australia
| | - Sharon R Lewin
- Department of Infectious Diseases, The University of Melbourne at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria 3000, Australia
- Victorian Infectious Diseases Service, 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
| | - Francesca Cavalieri
- Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy
- School of Science, RMIT University, Victoria 3000, Australia.
| | - Frank Caruso
- Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia.
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16
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Damstra HGJ, Mohar B, Eddison M, Akhmanova A, Kapitein LC, Tillberg PW. Visualizing cellular and tissue ultrastructure using Ten-fold Robust Expansion Microscopy (TREx). eLife 2022; 11:73775. [PMID: 35179128 PMCID: PMC8887890 DOI: 10.7554/elife.73775] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 01/30/2022] [Indexed: 12/18/2022] Open
Abstract
Expansion microscopy (ExM) is a powerful technique to overcome the diffraction limit of light microscopy that can be applied in both tissues and cells. In ExM, samples are embedded in a swellable polymer gel to physically expand the sample and isotropically increase resolution in x, y, and z. The maximum resolution increase is limited by the expansion factor of the gel, which is four-fold for the original ExM protocol. Variations on the original ExM method have been reported that allow for greater expansion factors but at the cost of ease of adoption or versatility. Here, we systematically explore the ExM recipe space and present a novel method termed Ten-fold Robust Expansion Microscopy (TREx) that, like the original ExM method, requires no specialized equipment or procedures. We demonstrate that TREx gels expand 10-fold, can be handled easily, and can be applied to both thick mouse brain tissue sections and cultured human cells enabling high-resolution subcellular imaging with a single expansion step. Furthermore, we show that TREx can provide ultrastructural context to subcellular protein localization by combining antibody-stained samples with off-the-shelf small-molecule stains for both total protein and membranes.
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Affiliation(s)
- Hugo G J Damstra
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Boaz Mohar
- Janelia Research Campus, HHMI, Ashburn, United States
| | - Mark Eddison
- Janelia Research Campus, HHMI, Ashburn, United States
| | - Anna Akhmanova
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Lukas C Kapitein
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Utrecht, Netherlands
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17
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Ferri G, Pesce L, Tesi M, Marchetti P, Cardarelli F. β-Cell Pathophysiology: A Review of Advanced Optical Microscopy Applications. Int J Mol Sci 2021; 22:ijms222312820. [PMID: 34884624 PMCID: PMC8657725 DOI: 10.3390/ijms222312820] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 11/24/2021] [Accepted: 11/24/2021] [Indexed: 11/30/2022] Open
Abstract
β-cells convert glucose (input) resulting in the controlled release of insulin (output), which in turn has the role to maintain glucose homeostasis. β-cell function is regulated by a complex interplay between the metabolic processing of the input, its transformation into second-messenger signals, and final mobilization of insulin-containing granules towards secretion of the output. Failure at any level in this process marks β-cell dysfunction in diabetes, thus making β-cells obvious potential targets for therapeutic purposes. Addressing quantitatively β-cell (dys)function at the molecular level in living samples requires probing simultaneously the spatial and temporal dimensions at the proper resolution. To this aim, an increasing amount of research efforts are exploiting the potentiality of biophysical techniques. In particular, using excitation light in the visible/infrared range, a number of optical-microscopy-based approaches have been tailored to the study of β-cell-(dys)function at the molecular level, either in label-free mode (i.e., exploiting intrinsic autofluorescence of cells) or by the use of organic/genetically-encoded fluorescent probes. Here, relevant examples from the literature are reviewed and discussed. Based on this, new potential lines of development in the field are drawn.
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Affiliation(s)
- Gianmarco Ferri
- NEST Laboratory, Scuola Normale Superiore, Piazza San Silvestro 12, 56127 Pisa, Italy; (G.F.); (L.P.)
| | - Luca Pesce
- NEST Laboratory, Scuola Normale Superiore, Piazza San Silvestro 12, 56127 Pisa, Italy; (G.F.); (L.P.)
| | - Marta Tesi
- Islet Cell Laboratory, Department of Clinical and Experimental Medicine, University of Pisa, 56127 Pisa, Italy; (M.T.); (P.M.)
| | - Piero Marchetti
- Islet Cell Laboratory, Department of Clinical and Experimental Medicine, University of Pisa, 56127 Pisa, Italy; (M.T.); (P.M.)
| | - Francesco Cardarelli
- NEST Laboratory, Scuola Normale Superiore, Piazza San Silvestro 12, 56127 Pisa, Italy; (G.F.); (L.P.)
- Correspondence:
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18
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Scardigli M, Pesce L, Brady N, Mazzamuto G, Gavryusev V, Silvestri L, Hof PR, Destrieux C, Costantini I, Pavone FS. Comparison of Different Tissue Clearing Methods for Three-Dimensional Reconstruction of Human Brain Cellular Anatomy Using Advanced Imaging Techniques. Front Neuroanat 2021; 15:752234. [PMID: 34867215 PMCID: PMC8632656 DOI: 10.3389/fnana.2021.752234] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 10/13/2021] [Indexed: 01/29/2023] Open
Abstract
The combination of tissue clearing techniques with advanced optical microscopy facilitates the achievement of three-dimensional (3D) reconstruction of macroscopic specimens at high resolution. Whole mouse organs or even bodies have been analyzed, while the reconstruction of the human nervous system remains a challenge. Although several tissue protocols have been proposed, the high autofluorescence and variable post-mortem conditions of human specimens negatively affect the quality of the images in terms of achievable transparency and staining contrast. Moreover, homogeneous staining of high-density epitopes, such as neuronal nuclear antigen (NeuN), creates an additional challenge. Here, we evaluated different tissue transformation approaches to find the best solution to uniformly clear and label all neurons in the human cerebral cortex using anti-NeuN antibodies in combination with confocal and light-sheet fluorescence microscopy (LSFM). Finally, we performed mesoscopic high-resolution 3D reconstruction of the successfully clarified and stained samples with LSFM.
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Affiliation(s)
- Marina Scardigli
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
- Department of Physics and Astronomy, University of Florence, Florence, Italy
| | - Luca Pesce
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
- Department of Physics and Astronomy, University of Florence, Florence, Italy
| | - Niamh Brady
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
| | - Giacomo Mazzamuto
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
- National Institute of Optics, National Research Council, Rome, Italy
| | - Vladislav Gavryusev
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
- Department of Physics and Astronomy, University of Florence, Florence, Italy
| | - Ludovico Silvestri
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
- Department of Physics and Astronomy, University of Florence, Florence, Italy
- National Institute of Optics, National Research Council, Rome, Italy
| | - Patrick R. Hof
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | | | - Irene Costantini
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
- National Institute of Optics, National Research Council, Rome, Italy
- Department of Biology, University of Florence, Florence, Italy
| | - Francesco S. Pavone
- European Laboratory for Non-linear Spectroscopy, University of Florence, Florence, Italy
- Department of Physics and Astronomy, University of Florence, Florence, Italy
- National Institute of Optics, National Research Council, Rome, Italy
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19
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Gorilak P, Pružincová M, Vachova H, Olšinová M, Schmidt Cernohorska M, Varga V. Expansion microscopy facilitates quantitative super-resolution studies of cytoskeletal structures in kinetoplastid parasites. Open Biol 2021; 11:210131. [PMID: 34465213 PMCID: PMC8437234 DOI: 10.1098/rsob.210131] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Expansion microscopy (ExM) has become a powerful super-resolution method in cell biology. It is a simple, yet robust approach, which does not require any instrumentation or reagents beyond those present in a standard microscopy facility. In this study, we used kinetoplastid parasites Trypanosoma brucei and Leishmania major, which possess a complex, yet well-defined microtubule-based cytoskeleton, to demonstrate that this method recapitulates faithfully morphology of structures as previously revealed by a combination of sophisticated electron microscopy (EM) approaches. Importantly, we also show that due to the rapidness of image acquisition and three-dimensional reconstruction of cellular volumes ExM is capable of complementing EM approaches by providing more quantitative data. This is demonstrated on examples of less well-appreciated microtubule structures, such as the neck microtubule of T. brucei or the pocket, cytosolic and multivesicular tubule-associated microtubules of L. major. We further demonstrate that ExM enables identifying cell types rare in a population, such as cells in mitosis and cytokinesis. Three-dimensional reconstruction of an entire volume of these cells provided details on the morphology of the mitotic spindle and the cleavage furrow. Finally, we show that established antibody markers of major cytoskeletal structures function well in ExM, which together with the ability to visualize proteins tagged with small epitope tags will facilitate studies of the kinetoplastid cytoskeleton.
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Affiliation(s)
- Peter Gorilak
- Laboratory of Cell Motility, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic,Charles University, Faculty of Science, Albertov 6, Prague, 128 00, Czech Republic
| | - Martina Pružincová
- Laboratory of Cell Motility, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Hana Vachova
- Laboratory of Cell Motility, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Marie Olšinová
- IMCF at BIOCEV, Faculty of Science, Charles University, Průmyslová 595, 252 50 Vestec, Czech Republic
| | - Marketa Schmidt Cernohorska
- Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
| | - Vladimir Varga
- Laboratory of Cell Motility, Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague, 14220, Czech Republic
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20
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Campbell LA, Pannoni KE, Savory NA, Lal D, Farris S. Protein-retention expansion microscopy for visualizing subcellular organelles in fixed brain tissue. J Neurosci Methods 2021; 361:109285. [PMID: 34242703 PMCID: PMC8370715 DOI: 10.1016/j.jneumeth.2021.109285] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/29/2021] [Accepted: 07/05/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Protein expansion microscopy (proExM) is a powerful technique that crosslinks proteins to a swellable hydrogel to physically expand and optically clear biological samples. The resulting increased resolution (~70 nm) and physical separation of labeled proteins make it an attractive tool for studying the localization of subcellular organelles in densely packed tissues, such as the brain. However, the digestion and expansion process greatly reduce fluorescence signals making it necessary to optimize ExM conditions per sample for specific end goals. NEW METHOD Here we compare the staining and digestion conditions of existing proExM workflows to identify the optimal protocol for visualizing subcellular organelles (mitochondria and the Golgi apparatus) within reporter-labeled neurons in fixed mouse brain tissue. RESULTS We found that immunostaining before proExM and using a proteinase K based digestion for 8 h consistently resulted in robust fluorescence retention for immunolabeled subcellular organelles and genetically-encoded reporters. COMPARISON WITH EXISTING METHODS With these methods, we more accurately quantified mitochondria size and number and better visualized Golgi ultrastructure in individual CA2 neurons in the mouse hippocampus. CONCLUSIONS This organelle optimized proExM protocol will be broadly useful for investigators interested in visualizing the spatial distribution of immunolabeled subcellular organelles in various reporter mouse lines, reducing effort, time and resources on the optimization process.
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Affiliation(s)
- Logan A Campbell
- Fralin Biomedical Research Institute, Center for Neurobiology Research, Virginia Tech Carilion, Roanoke, VA, USA
| | - Katy E Pannoni
- Fralin Biomedical Research Institute, Center for Neurobiology Research, Virginia Tech Carilion, Roanoke, VA, USA
| | - Niesha A Savory
- Fralin Biomedical Research Institute, Center for Neurobiology Research, Virginia Tech Carilion, Roanoke, VA, USA; School of Neuroscience, Virginia Tech, Blacksburg, VA, USA
| | - Dinesh Lal
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
| | - Shannon Farris
- Fralin Biomedical Research Institute, Center for Neurobiology Research, Virginia Tech Carilion, Roanoke, VA, USA; Virginia Tech Carilion School of Medicine, Roanoke, VA, USA; Department of Biomedical Sciences & Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA.
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21
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Gallagher BR, Zhao Y. Expansion microscopy: A powerful nanoscale imaging tool for neuroscientists. Neurobiol Dis 2021; 154:105362. [PMID: 33813047 PMCID: PMC8600979 DOI: 10.1016/j.nbd.2021.105362] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 03/26/2021] [Accepted: 03/31/2021] [Indexed: 01/13/2023] Open
Abstract
One of the biggest unsolved questions in neuroscience is how molecules and neuronal circuitry create behaviors, and how their misregulation or dysfunction results in neurological disease. Light microscopy is a vital tool for the study of neural molecules and circuits. However, the fundamental optical diffraction limit precludes the use of conventional light microscopy for sufficient characterization of critical signaling compartments and nanoscopic organizations of synapse-associated molecules. We have witnessed rapid development of super-resolution microscopy methods that circumvent the resolution limit by controlling the number of emitting molecules in specific imaging volumes and allow highly resolved imaging in the 10-100 nm range. Most recently, Expansion Microscopy (ExM) emerged as an alternative solution to overcome the diffraction limit by physically magnifying biological specimens, including nervous systems. Here, we discuss how ExM works in general and currently available ExM methods. We then review ExM imaging in a wide range of nervous systems, including Caenorhabditis elegans, Drosophila, zebrafish, mouse, and human, and their applications to synaptic imaging, neuronal tracing, and the study of neurological disease. Finally, we provide our prospects for expansion microscopy as a powerful nanoscale imaging tool in the neurosciences.
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Affiliation(s)
- Brendan R Gallagher
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Yongxin Zhao
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, USA.
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22
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Zhu C, Wang A, Chen L, Guo L, Ye J, Chen Q, Wang Q, Yao G, Xia Q, Cai T, Guo J, Yang Z, Sun Z, Xu Y, Lu G, Zhang Z, Cao J, Liu Y, Xu H. Measurement of expansion factor and distortion for expansion microscopy using isolated renal glomeruli as landmarks. JOURNAL OF BIOPHOTONICS 2021; 14:e202100001. [PMID: 33856738 DOI: 10.1002/jbio.202100001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 03/14/2021] [Accepted: 04/08/2021] [Indexed: 06/12/2023]
Abstract
Expansion microscopy has enabled super resolution imaging of biological samples. The accurate measurement of expansion factor and distortion typically requires locating and imaging the same region of interest in the sample before and after expansion, which is often time-consuming to achieve. Here we introduce a convenient method for relocation by utilizing isolated porcine glomeruli as landmarks during expansion. Following heat denaturation and proteinase K digestion protocols, the glomeruli exhibit expansion factor of 3.5 to 4 (only 7%-16% less expanded than the hydrogel), and 1% to 2% of relative distortion. Due to its appropriate size of 100 to 300 μm, the location of the glomerulus in the sample are visible to eyes, while its detailed shape only requires bright field microscopy. For expansion factors ranging from 3 to 10, the region in the vicinity of the glomerulus can be easily re-identified, and sometimes allows quantification of expansion factor and distortion under bright field without fluorescent labels.
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Affiliation(s)
- Chen Zhu
- Institute for Advanced Study, Soochow University, Suzhou, China
- School of Optoelectronic Science and Engineering, Soochow University, Suzhou, China
| | - Aidong Wang
- The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Lili Chen
- The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Liangsheng Guo
- The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Jiajia Ye
- Institute for Advanced Study, Soochow University, Suzhou, China
- School of Physical Science and Technology, Soochow University, Suzhou, China
| | - Qilin Chen
- Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Qi Wang
- Institute for Advanced Study, Soochow University, Suzhou, China
- School of Optoelectronic Science and Engineering, Soochow University, Suzhou, China
| | - Guojia Yao
- Institute for Advanced Study, Soochow University, Suzhou, China
- School of Physical Science and Technology, Soochow University, Suzhou, China
| | - Qin Xia
- Institute for Advanced Study, Soochow University, Suzhou, China
- School of Physical Science and Technology, Soochow University, Suzhou, China
| | - Tianyu Cai
- Institute for Advanced Study, Soochow University, Suzhou, China
- School of Physical Science and Technology, Soochow University, Suzhou, China
| | - Jiayun Guo
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Zhenyu Yang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Zhenglong Sun
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China
| | - Yuwei Xu
- The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Guoyuan Lu
- The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zexin Zhang
- Institute for Advanced Study, Soochow University, Suzhou, China
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, China
| | - Jingyuan Cao
- Department of Nephrology, Taizhou People's Hospital, the Fifth Affiliated Hospital of Nantong University, Taizhou, China
| | - Ying Liu
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, China
| | - Huizhong Xu
- Institute for Advanced Study, Soochow University, Suzhou, China
- School of Physical Science and Technology, Soochow University, Suzhou, China
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23
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Büttner M, Lagerholm CB, Waithe D, Galiani S, Schliebs W, Erdmann R, Eggeling C, Reglinski K. Challenges of Using Expansion Microscopy for Super-resolved Imaging of Cellular Organelles. Chembiochem 2021; 22:686-693. [PMID: 33049107 PMCID: PMC7894168 DOI: 10.1002/cbic.202000571] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 10/07/2020] [Indexed: 12/26/2022]
Abstract
Expansion microscopy (ExM) has been successfully used to improve the spatial resolution when imaging tissues by optical microscopy. In ExM, proteins of a fixed sample are crosslinked to a swellable acrylamide gel, which expands when incubated in water. Therefore, ExM allows enlarged subcellular structures to be resolved that would otherwise be hidden to standard confocal microscopy. Herein, we aim to validate ExM for the study of peroxisomes, mitochondria, nuclei and the plasma membrane. Upon comparison of the expansion factors of these cellular compartments in HEK293 cells within the same gel, we found significant differences, of a factor of above 2, in expansion factors. For peroxisomes, the expansion factor differed even between peroxisomal membrane and matrix marker; this underlines the need for a thorough validation of expansion factors of this powerful technique. We further give an overview of possible quantification methods for the determination of expansion factors of intracellular organelles, and we highlight some potentials and challenges.
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Affiliation(s)
- Maximilian Büttner
- MRC Human Immunology Unit MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
- Institute for Anatomy and Cell BiologyMartin-Luther-University Halle-WittenbergGroße Steinstraße 5206108HalleGermany
| | - Christoffer B. Lagerholm
- Wolfson Imaging Centre MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
| | - Dominic Waithe
- MRC Human Immunology Unit MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
- Wolfson Imaging Centre MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
| | - Silvia Galiani
- MRC Human Immunology Unit MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
- Wolfson Imaging Centre MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
| | - Wolfgang Schliebs
- Institute of Biochemistry and Pathobiochemistry Systemic BiochemistryRuhr-University BochumUniversitätsstraße 15044801BochumGermany
| | - Ralf Erdmann
- Institute of Biochemistry and Pathobiochemistry Systemic BiochemistryRuhr-University BochumUniversitätsstraße 15044801BochumGermany
| | - Christian Eggeling
- MRC Human Immunology Unit MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
- Leibniz-Institute of Photonic Technologies & Institute of Applied Optic and BiophysicsFriedrich-Schiller University JenaMax-Wien-Platz 107743JenaGermany
| | - Katharina Reglinski
- MRC Human Immunology Unit MRC Weatherall Institute of Molecular MedicineUniversity of Oxford Headley WayOxfordOX3 9DSUK
- Leibniz-Institute of Photonic Technologies & Institute of Applied Optic and BiophysicsFriedrich-Schiller University JenaMax-Wien-Platz 107743JenaGermany
- University Hospital JenaBachstraße 1807743JenaGermany
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24
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Zhao J, Lai HM, Qi Y, He D, Sun H. Current Status of Tissue Clearing and the Path Forward in Neuroscience. ACS Chem Neurosci 2021; 12:5-29. [PMID: 33326739 DOI: 10.1021/acschemneuro.0c00563] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Due to the complexity and limited availability of human brain tissues, for decades, pathologists have sought to maximize information gained from individual samples, based on which (patho)physiological processes could be inferred. Recently, new understandings of chemical and physical properties of biological tissues and multiple chemical profiling have given rise to the development of scalable tissue clearing methods allowing superior optical clearing of across-the-scale samples. In the past decade, tissue clearing techniques, molecular labeling methods, advanced laser scanning microscopes, and data visualization and analysis have become commonplace. Combined, they have made 3D visualization of brain tissues with unprecedented resolution and depth widely accessible. To facilitate further advancements and applications, here we provide a critical appraisal of these techniques. We propose a classification system of current tissue clearing and expansion methods that allows users to judge the applicability of individual ones to their questions, followed by a review of the current progress in molecular labeling, optical imaging, and data processing to demonstrate the whole 3D imaging pipeline based on tissue clearing and downstream techniques for visualizing the brain. We also raise the path forward of tissue-clearing-based imaging technology, that is, integrating with state-of-the-art techniques, such as multiplexing protein imaging, in situ signal amplification, RNA detection and sequencing, super-resolution imaging techniques, multiomics studies, and deep learning, for drawing the complete atlas of the human brain and building a 3D pathology platform for central nervous system disorders.
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Affiliation(s)
- Jiajia Zhao
- Department of Neurosurgery, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Zhujiang Hospital, Southern Medical University, Guangzhou 510515, China
- The Second Clinical Medical College, Southern Medical University, Guangzhou 510515, China
| | - Hei Ming Lai
- Department of Psychiatry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Yuwei Qi
- Department of Neurosurgery, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Zhujiang Hospital, Southern Medical University, Guangzhou 510515, China
- The Second Clinical Medical College, Southern Medical University, Guangzhou 510515, China
| | - Dian He
- Department of Neurosurgery, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Zhujiang Hospital, Southern Medical University, Guangzhou 510515, China
- The Second Clinical Medical College, Southern Medical University, Guangzhou 510515, China
| | - Haitao Sun
- Department of Neurosurgery, The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Zhujiang Hospital, Southern Medical University, Guangzhou 510515, China
- The Second Clinical Medical College, Southern Medical University, Guangzhou 510515, China
- Microbiome Medicine Center, Department of Laboratory Medicine, Clinical Biobank Center, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China
- Key Laboratory of Mental Health of the Ministry of Education, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Southern Medical University, Guangzhou 510515, China
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25
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Bianchini P, Pesce L, Diaspro A. Expansion microscopy at the nanoscale: The nuclear pore complex as a fiducial landmark. Methods Cell Biol 2020; 161:275-295. [PMID: 33478693 DOI: 10.1016/bs.mcb.2020.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Expansion microscopy (ExM) is a magnification method that allows achieving super-resolved images using a conventional light microscope. In ExM, biomolecules, fluorescent proteins, and dyes are functionalized with specific handles to link a dense polyelectrolyte hydrogel, which can achieve an isotropic expansion of 4.5-fold in water. The use of ExM coupled with STED nanoscopy allows examining macromolecular machinery in life science, like the nuclear pore complex (NPC). In particular, in this chapter, we show a general protocol for labeling one of its subunit, i.e. the Nup153. Such method shows the nanoscale isotropy of the expansion process and enables precise measurement of the expansion factor. Finally, we used ExM for the visualization of a peculiar nuclear invagination in normal and aged cells.
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Affiliation(s)
- Paolo Bianchini
- Nanoscopy and NIC@IIT, CHT, Istituto Italiano di Tecnologia, Genova, Italy.
| | - Luca Pesce
- Nanoscopy and NIC@IIT, CHT, Istituto Italiano di Tecnologia, Genova, Italy
| | - Alberto Diaspro
- Nanoscopy and NIC@IIT, CHT, Istituto Italiano di Tecnologia, Genova, Italy; DIFILAB, Dipartimento di Fisica, Universita` degli Studi di Genova, Genova, Italy
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26
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Edwards SJ, Carannante V, Kuhnigk K, Ring H, Tararuk T, Hallböök F, Blom H, Önfelt B, Brismar H. High-Resolution Imaging of Tumor Spheroids and Organoids Enabled by Expansion Microscopy. Front Mol Biosci 2020; 7:208. [PMID: 33195398 PMCID: PMC7543521 DOI: 10.3389/fmolb.2020.00208] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/29/2020] [Indexed: 12/12/2022] Open
Abstract
Three-dimensional cell cultures are able to better mimic the physiology and cellular environments found in tissues in vivo compared to cells grown in two dimensions. In order to study the structure and function of cells in 3-D cultures, light microscopy is frequently used. The preparation of 3-D cell cultures for light microscopy is often destructive, including physical sectioning of the samples, which can result in the loss of 3-D information. In order to probe the structure of 3-D cell cultures at high resolution, we have explored the use of expansion microscopy and compared it to a simple immersion clearing protocol. We provide a practical method for the study of spheroids, organoids and tumor-infiltrating immune cells at high resolution without the loss of spatial organization. Expanded samples are highly transparent, enabling high-resolution imaging over extended volumes by significantly reducing light scatter and absorption. In addition, the hydrogel-like nature of expanded samples enables homogenous antibody labeling of dense epitopes throughout the sample volume. The improved labeling and image quality achieved in expanded samples revealed details in the center of the organoid which were previously only observable following serial sectioning. In comparison to chemically cleared spheroids, the improved signal-to-background ratio of expanded samples greatly improved subsequent methods for image segmentation and analysis.
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Affiliation(s)
- Steven J Edwards
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Valentina Carannante
- Department of Microbiology, Tumor and Cell Biology, Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden
| | - Kyra Kuhnigk
- Center for Hematology and Regenerative Medicine, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Henrik Ring
- Department of Neuroscience, BMC, Uppsala University, Uppsala, Sweden
| | - Tatsiana Tararuk
- Department of Neuroscience, BMC, Uppsala University, Uppsala, Sweden
| | - Finn Hallböök
- Department of Neuroscience, BMC, Uppsala University, Uppsala, Sweden
| | - Hans Blom
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Björn Önfelt
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
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27
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Jacquemet G, Carisey AF, Hamidi H, Henriques R, Leterrier C. The cell biologist's guide to super-resolution microscopy. J Cell Sci 2020; 133:133/11/jcs240713. [PMID: 32527967 DOI: 10.1242/jcs.240713] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Fluorescence microscopy has become a ubiquitous method to observe the location of specific molecular components within cells. However, the resolution of light microscopy is limited by the laws of diffraction to a few hundred nanometers, blurring most cellular details. Over the last two decades, several techniques - grouped under the 'super-resolution microscopy' moniker - have been designed to bypass this limitation, revealing the cellular organization down to the nanoscale. The number and variety of these techniques have steadily increased, to the point that it has become difficult for cell biologists and seasoned microscopists alike to identify the specific technique best suited to their needs. Available techniques include image processing strategies that generate super-resolved images, optical imaging schemes that overcome the diffraction limit and sample manipulations that expand the size of the biological sample. In this Cell Science at a Glance article and the accompanying poster, we provide key pointers to help users navigate through the various super-resolution methods by briefly summarizing the principles behind each technique, highlighting both critical strengths and weaknesses, as well as providing example images.
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Affiliation(s)
- Guillaume Jacquemet
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland .,Faculty of Science and Engineering, Cell Biology, Åbo Akademi University, 20520 Turku, Finland
| | - Alexandre F Carisey
- William T. Shearer Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, 1102 Bates Street, Houston 77030 TX, USA
| | - Hellyeh Hamidi
- Turku Bioscience Centre, University of Turku and Åbo Akademi University, FI-20520 Turku, Finland
| | - Ricardo Henriques
- University College London, London WC1E 6BT, UK .,The Francis Crick Institute, London NW1 1AT, UK
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28
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Enhanced expansion microscopy to measure nanoscale structural and biochemical remodeling in single cells. Methods Cell Biol 2020; 161:147-180. [PMID: 33478687 DOI: 10.1016/bs.mcb.2020.04.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Resolution is a key feature in microscopy which allows the visualization of the fine structure of cells. Much of the life processes within these cells depend on the three-dimensional (3D) complexity of these structures. Optical super-resolution microscopies are currently the preferred choice of molecular and cell biologists who seek to visualize the organization of specific protein species at the nanometer scale. Traditional super-resolution microscopy techniques have often been limited by sample thickness, axial resolution, specialist optical instrumentation and computationally-demanding software for assembling the images. In this chapter we detail the protocol, "enhanced expansion microscopy" (EExM), which combines X10 expansion microscopy with Airyscan confocal microscopy. EExM enables 15nm lateral (and 35nm axial) resolution, and is a relatively cheap, accessible option allowing single protein resolution for the non-specialist optical microscopists. We illustrate how EExM has been utilized for mapping the 3D topology of intracellular protein arrays at sample depths which are not always compatible with some of the traditional super-resolution techniques. We demonstrate that antibody markers can recognize and map post-translational modifications of individual proteins in addition to their 3D positions. Finally, we discuss the current uncertainties and validations in EExM which include the isotropy in gel expansion and assessment of the expansion factor (of resolution improvement).
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29
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Faulkner EL, Thomas SG, Neely RK. An introduction to the methodology of expansion microscopy. Int J Biochem Cell Biol 2020; 124:105764. [PMID: 32407880 DOI: 10.1016/j.biocel.2020.105764] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/30/2020] [Accepted: 05/03/2020] [Indexed: 01/21/2023]
Abstract
Expansion microscopy is a novel, fluorescence imaging technique, which allows three-dimensional nanoscale imaging of specimens on a conventional fluorescence microscope. This is achieved through an innovative sample treatment, which culminates in approximately 4.5-fold expansion of specimens in each dimension. This allows 70 nm lateral and 200 nm axial resolution. To further develop application of the technique, there has been considerable focus on improving the methodology by i) extending the efficacy of labelling, ii) enabling multi-colour labelling of different biomolecules simultaneously, iii) further improving resolving power through alterations to sample preparation and iv) by combination of expansion microscopy with other well-established super resolution techniques. This review will highlight some of these recent advances and suggest ways that the technique could be developed further in the future.
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Affiliation(s)
- Emma L Faulkner
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Steven G Thomas
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham, UK; Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK
| | - Robert K Neely
- Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham and University of Nottingham, Midlands, UK; School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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30
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Vanheusden M, Vitale R, Camacho R, Janssen KPF, Acke A, Rocha S, Hofkens J. Fluorescence Photobleaching as an Intrinsic Tool to Quantify the 3D Expansion Factor of Biological Samples in Expansion Microscopy. ACS OMEGA 2020; 5:6792-6799. [PMID: 32258914 PMCID: PMC7114699 DOI: 10.1021/acsomega.0c00118] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 03/05/2020] [Indexed: 05/06/2023]
Abstract
Four years after its first report, expansion microscopy (ExM) is now being routinely applied in laboratories worldwide to achieve super-resolution imaging on conventional fluorescence microscopes. By chemically anchoring all molecules of interest to the polymer meshwork of an expandable hydrogel, their physical distance is increased by a factor of ∼4-5× upon dialysis in water, resulting in an imprint of the original sample with a lateral resolution up to 50-70 nm. To ensure a correct representation of the original spatial distribution of the molecules, it is crucial to confirm that the expansion is isotropic, preferentially in all three dimensions. To address this, we present an approach to evaluate the local expansion factor within a biological sample and in all three dimensions. We use photobleaching to introduce well-defined three-dimensional (3D) features in the cell and, by comparing the size and shape pre- and postexpansion, these features can be used as an intrinsic ruler. In addition, our method is capable of pointing out sample distortions and can be used as a quality control tool for expansion microscopy experiments in biological samples.
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Affiliation(s)
| | | | - Rafael Camacho
- Department of Chemistry, KU Leuven, Leuven 3000, Belgium
| | | | - Aline Acke
- Department of Chemistry, KU Leuven, Leuven 3000, Belgium
| | - Susana Rocha
- Department of Chemistry, KU Leuven, Leuven 3000, Belgium
| | - Johan Hofkens
- Department of Chemistry, KU Leuven, Leuven 3000, Belgium
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31
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Lanzanò L. Counting the Components of Protein Complexes in the Nuclear Envelope. Biophys J 2020; 118:989-990. [PMID: 32017890 DOI: 10.1016/j.bpj.2020.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/07/2020] [Accepted: 01/09/2020] [Indexed: 11/28/2022] Open
Affiliation(s)
- Luca Lanzanò
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy.
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32
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Thevathasan JV, Kahnwald M, Cieśliński K, Hoess P, Peneti SK, Reitberger M, Heid D, Kasuba KC, Hoerner SJ, Li Y, Wu YL, Mund M, Matti U, Pereira PM, Henriques R, Nijmeijer B, Kueblbeck M, Sabinina VJ, Ellenberg J, Ries J. Nuclear pores as versatile reference standards for quantitative superresolution microscopy. Nat Methods 2019; 16:1045-1053. [PMID: 31562488 PMCID: PMC6768092 DOI: 10.1038/s41592-019-0574-9] [Citation(s) in RCA: 205] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 08/14/2019] [Indexed: 12/18/2022]
Abstract
Quantitative fluorescence and superresolution microscopy are often limited by insufficient data quality or artifacts. In this context, it is essential to have biologically relevant control samples to benchmark and optimize the quality of microscopes, labels and imaging conditions. Here, we exploit the stereotypic arrangement of proteins in the nuclear pore complex as in situ reference structures to characterize the performance of a variety of microscopy modalities. We created four genome edited cell lines in which we endogenously labeled the nucleoporin Nup96 with mEGFP, SNAP-tag, HaloTag or the photoconvertible fluorescent protein mMaple. We demonstrate their use (1) as three-dimensional resolution standards for calibration and quality control, (2) to quantify absolute labeling efficiencies and (3) as precise reference standards for molecular counting. These cell lines will enable the broader community to assess the quality of their microscopes and labels, and to perform quantitative, absolute measurements.
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Affiliation(s)
- Jervis Vermal Thevathasan
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | | | | | - Philipp Hoess
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Sudheer Kumar Peneti
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - Manuel Reitberger
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Division of Stem Cells and Cancer, German Cancer Research Center, Heidelberg, Germany
| | - Daniel Heid
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Department for Applied Tumor Biology, Heidelberg University Hospital, Heidelberg, Germany
| | - Krishna Chaitanya Kasuba
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Eidgenössische Technische Hochschule Zurich, Department of Biosystems Science and Engineering, Basel, Switzerland
| | - Sarah Janice Hoerner
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences and Interdisciplinary Center for Neuroscience, Heidelberg University, Heidelberg, Germany
| | - Yiming Li
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Yu-Le Wu
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Faculty of Biosciences, Heidelberg University, Heidelberg, Germany
| | - Markus Mund
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
- Department of Biochemistry, University of Geneva, Science 2, Genève, Switzerland
| | - Ulf Matti
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Pedro Matos Pereira
- MRC-Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Ricardo Henriques
- MRC-Laboratory for Molecular Cell Biology, University College London, London, UK
| | | | | | | | - Jan Ellenberg
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany
| | - Jonas Ries
- EMBL, Cell Biology and Biophysics, Heidelberg, Germany.
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33
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Molecular organization of mammalian meiotic chromosome axis revealed by expansion STORM microscopy. Proc Natl Acad Sci U S A 2019; 116:18423-18428. [PMID: 31444302 DOI: 10.1073/pnas.1902440116] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
During prophase I of meiosis, chromosomes become organized as loop arrays around the proteinaceous chromosome axis. As homologous chromosomes physically pair and recombine, the chromosome axis is integrated into the tripartite synaptonemal complex (SC) as this structure's lateral elements (LEs). While the components of the mammalian chromosome axis/LE-including meiosis-specific cohesin complexes, the axial element proteins SYCP3 and SYCP2, and the HORMA domain proteins HORMAD1 and HORMAD2-are known, the molecular organization of these components within the axis is poorly understood. Here, using expansion microscopy coupled with 2-color stochastic optical reconstruction microscopy (STORM) imaging (ExSTORM), we address these issues in mouse spermatocytes at a resolution of 10 to 20 nm. Our data show that SYCP3 and the SYCP2 C terminus, which are known to form filaments in vitro, form a compact core around which cohesin complexes, HORMADs, and the N terminus of SYCP2 are arrayed. Overall, our study provides a detailed structural view of the meiotic chromosome axis, a key organizational and regulatory component of meiotic chromosomes.
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