1
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Calì C. Regulated exocytosis from astrocytes: a matter of vesicles? Front Neurosci 2024; 18:1393165. [PMID: 38800570 PMCID: PMC11116621 DOI: 10.3389/fnins.2024.1393165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 04/30/2024] [Indexed: 05/29/2024] Open
Affiliation(s)
- Corrado Calì
- Department of Neuroscience “Rita Levi Montalcini”, University of Turin, Turin, Italy
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy
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2
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Faber T, McConville JT, Lamprecht A. Focused ion beam-scanning electron microscopy provides novel insights of drug delivery phenomena. J Control Release 2024; 366:312-327. [PMID: 38161031 DOI: 10.1016/j.jconrel.2023.12.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/23/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
Scanning electron microscopy (SEM) has long been a standard tool for morphological analyses, providing sub micrometer resolution of pharmaceutical formulations. However, analysis of internal morphologies of such formulations can often be biased due to the introduction of artifacts that originate from sample preparation. A recent advancement in SEM, is the focused ion beam scanning electron microscopy (FIB-SEM). This technique uses a focused ion beam (FIB) to remove material with nanometer precision, to provide virtually sample-independent access to sub-surface structures. The FIB can be combined with SEM imaging capabilities within the same instrumentation. As a powerful analytical tool, electron microscopy and FIB-milling are performed sequentially to produce high-resolution 3D models of structural peculiarities of diverse drug delivery systems or their behavior in a biological environment, i.e. intracellular or -tissue distribution. This review paper briefly describes the technical background of the method, outlines a wide array of potential uses within the drug delivery field, and focuses on intracellular transport where high-resolution images are an essential tool for mechanistical insights.
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Affiliation(s)
- Thilo Faber
- Department of Pharmaceutics, Institute of Pharmacy, University of Bonn, Bonn, Germany
| | - Jason T McConville
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, USA
| | - Alf Lamprecht
- Department of Pharmaceutics, Institute of Pharmacy, University of Bonn, Bonn, Germany; Université de Franche-Comté, INSERM UMR1098 Right, Besançon, France.
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3
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McLaughlin MR, Weaver SA, Syed F, Evans-Molina C. Advanced Imaging Techniques for the Characterization of Subcellular Organelle Structure in Pancreatic Islet β Cells. Compr Physiol 2023; 14:5243-5267. [PMID: 38158370 DOI: 10.1002/cphy.c230002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Type 2 diabetes (T2D) affects more than 32.3 million individuals in the United States, creating an economic burden of nearly $966 billion in 2021. T2D results from a combination of insulin resistance and inadequate insulin secretion from the pancreatic β cell. However, genetic and physiologic data indicate that defects in β cell function are the chief determinant of whether an individual with insulin resistance will progress to a diagnosis of T2D. The subcellular organelles of the insulin secretory pathway, including the endoplasmic reticulum, Golgi apparatus, and secretory granules, play a critical role in maintaining the heavy biosynthetic burden of insulin production, processing, and secretion. In addition, the mitochondria enable the process of insulin release by integrating the metabolism of nutrients into energy output. Advanced imaging techniques are needed to determine how changes in the structure and composition of these organelles contribute to the loss of insulin secretory capacity in the β cell during T2D. Several microscopy techniques, including electron microscopy, fluorescence microscopy, and soft X-ray tomography, have been utilized to investigate the structure-function relationship within the β cell. In this overview article, we will detail the methodology, strengths, and weaknesses of each approach. © 2024 American Physiological Society. Compr Physiol 14:5243-5267, 2024.
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Affiliation(s)
- Madeline R McLaughlin
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Staci A Weaver
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA
- The Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Farooq Syed
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
- The Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Carmella Evans-Molina
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, USA
- The Center for Diabetes and Metabolic Diseases, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
- Roudebush VA Medical Center, Indianapolis, Indiana, USA
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4
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White IJ, Burden JJ. A practical guide to starting SEM array tomography-An accessible volume EM technique. Methods Cell Biol 2023; 177:171-196. [PMID: 37451766 DOI: 10.1016/bs.mcb.2022.12.023] [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: 02/18/2023]
Abstract
The techniques collectively known as volume electron microscopy (vEM) each come with their own advantages and challenges, making them more or less suitable for any specific project. SEM array tomography (SEM-AT) is certainly no different in this respect. Requiring microtomy skills, and involving more data alignment post imaging, SEM-AT presents challenges to its users, nevertheless, as perhaps the most flexible, cost effective and potentially accessible vEM approach to regular EM facilities, it benefits those same users with multiple advantages due to its inherently non-destructive nature. The general principles and advantages/disadvantages of SEM-AT are described here, together with a step-by-step guide to the workflow, from block trimming, sectioning and collection on coverslips, to alignment of the high-resolution 3D dataset. With a suitable SEM/backscatter electron detector setup, and equipment readily found in an electron microscopy lab, it should be possible to begin to acquire 3D ultrastructural data. With the addition of appropriate SEM-AT imaging software, this process can be significantly enhanced to automatically image hundreds, potentially thousands, of sections. Hardware and software advances and future improvements will only make this easier, to the extent that SEM-AT could become a routine vEM technique throughout the world, rather than the privilege of a small number of experts in limited specialist facilities.
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Affiliation(s)
- Ian J White
- LMCB, University College London, London, United Kingdom
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5
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Mitchell RL, Dunlop T, Volkenandt T, Russell J, Davies P, Spooner S, Pleydell-Pearce C, Johnston R. Methods to expose subsurface objects of interest identified from 3D imaging: The intermediate sample preparation stage in the correlative microscopy workflow. J Microsc 2023; 289:107-127. [PMID: 36399637 DOI: 10.1111/jmi.13159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 09/13/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022]
Abstract
The correlative imaging workflow is a method of combining information and data across modes (e.g. SEM, X-ray CT, FIB-SEM), scales (cm to nm) and dimensions (2D-3D-4D), providing a more holistic interpretation of the research question. Often, subsurface objects of interest (e.g. inclusions, pores, cracks, defects in multilayered samples) are identified from initial exploratory nondestructive 3D tomographic imaging (e.g. X-ray CT, XRM), and those objects need to be studied using additional techniques to obtain, for example, 2D chemical or crystallographic data. Consequently, an intermediate sample preparation step needs to be completed, where a targeted amount of sample surface material is removed, exposing and revealing the object of interest. At present, there is not one singular technique for removing varied thicknesses at high resolution and on a range of scales from cm to nm. Here, we review the manual and automated options currently available for targeted sample material removal, with a focus on those methods which are readily accessible in most laboratories. We summarise the approaches for manual grinding and polishing, automated grinding and polishing, microtome/ultramicrotome, and broad-beam ion milling (BBIM), with further review of other more specialist techniques including serial block face electron microscopy (SBF-SEM), and ion milling and laser approaches such as FIB-SEM, Xe plasma FIB-SEM, and femtosecond laser/LaserFIB. We also address factors which may influence the decision on a particular technique, including the composition, shape and size of the samples, sample mounting limitations, the amount of surface material to be removed, the accuracy and/or resolution of peripheral parts, the accuracy and/or resolution of the technique/instrumentation, and other more general factors such as accessibility to instrumentation, costs, and the time taken for experimentation. It is hoped that this study will provide researchers with a range of options for removal of specific amounts of sample surface material to reach subsurface objects of interest in both correlative and non-correlative workflows.
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Affiliation(s)
- R L Mitchell
- Advanced Imaging of Materials (AIM) Core Facility, Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea, UK
- Sheffield Tomography Centre (STC), Kroto Research Institute, The University of Sheffield, North Campus, Sheffield, UK
| | - T Dunlop
- Advanced Imaging of Materials (AIM) Core Facility, Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea, UK
| | | | - J Russell
- Advanced Imaging of Materials (AIM) Core Facility, Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea, UK
| | - P Davies
- Advanced Imaging of Materials (AIM) Core Facility, Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea, UK
| | - S Spooner
- Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea, UK
| | - C Pleydell-Pearce
- Advanced Imaging of Materials (AIM) Core Facility, Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea, UK
| | - R Johnston
- Advanced Imaging of Materials (AIM) Core Facility, Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea, UK
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6
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Wouterlood FG. Techniques to Render Dendritic Spines Visible in the Microscope. ADVANCES IN NEUROBIOLOGY 2023; 34:69-102. [PMID: 37962794 DOI: 10.1007/978-3-031-36159-3_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
A tiny detail visible on certain neurons at the limit of resolution in light microscopy went in 130 years of neuroscience research through a dazzling career from suspicious staining artifact to what we recognize today as a complex postsynaptic molecular machine: the dendritic spine.This chapter deals with techniques to make spines visible. The original technique, Golgi silver staining, is still being used today. Electron microscopy and automated field ion beam scanning electron microscopy are ultrahigh resolution techniques, albeit specialized. Other methods are intracellular injection, uptake of dyes, and recently the exploitation of genetically modified animals in which certain neurons express fluorescent protein in all their processes, including the nooks and crannies of their dendritic spines.
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Affiliation(s)
- Floris G Wouterlood
- Department of Anatomy & Neurosciences, Amsterdam UMC, Amsterdam, The Netherlands
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7
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Three-dimensional SEM, TEM, and STEM for analysis of large-scale biological systems. Histochem Cell Biol 2022; 158:203-211. [PMID: 35829815 PMCID: PMC9399040 DOI: 10.1007/s00418-022-02117-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/07/2022] [Indexed: 12/12/2022]
Abstract
A major aim in structural cell biology is to analyze intact cells in three dimensions, visualize subcellular structures, and even localize proteins at the best possible resolution in three dimensions. Though recently developed electron microscopy tools such as electron tomography, or three-dimensional (3D) scanning electron microscopy, offer great resolution in three dimensions, the challenge is that, the better the resolution, usually the smaller the volume under investigation. Several different approaches to overcome this challenge were presented at the Microscopy Conference in Vienna in 2021. These tools include array tomography, batch tomography, or scanning transmission electron tomography, all of which can nowadays be extended toward correlative light and electron tomography, with greatly increased 3D information. Here, we review these tools, describe the underlying procedures, and discuss their advantages and limits.
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8
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Zhou F, Chen B, Chen X, Han H. Neuronal Morphological Model-Driven Image Registration for Serial Electron Microscopy Sections. Front Hum Neurosci 2022; 16:846599. [PMID: 35601904 PMCID: PMC9119086 DOI: 10.3389/fnhum.2022.846599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 04/04/2022] [Indexed: 11/15/2022] Open
Abstract
Registration of a series of the two-dimensional electron microscope (EM) images of the brain tissue into volumetric form is an important technique that can be used for neuronal circuit reconstruction. However, complex appearance changes of neuronal morphology in adjacent sections bring difficulty in finding correct correspondences, making serial section neural image registration challenging. To solve this problem, we consider whether there are such stable "markers" in the neural images to alleviate registration difficulty. In this paper, we employ the spherical deformation model to simulate the local neuron structure and analyze the relationship between registration accuracy and neuronal structure shapes in two adjacent sections. The relevant analysis proves that regular circular structures in the section images are instrumental in seeking robust corresponding relationships. Then, we design a new serial section image registration framework driven by this neuronal morphological model, fully utilizing the characteristics of the anatomical structure of nerve tissue and obtaining more reasonable corresponding relationships. Specifically, we leverage a deep membrane segmentation network and neural morphological physical selection model to select the stable rounded regions in neural images. Then, we combine feature extraction and global optimization of correspondence position to obtain the deformation field of multiple images. Experiments on real and synthetic serial EM section neural image datasets have demonstrated that our proposed method could achieve more reasonable and reliable registration results, outperforming the state-of-the-art approaches in qualitative and quantitative analysis.
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Affiliation(s)
- Fangxu Zhou
- School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
- Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Bohao Chen
- Institute of Automation, Chinese Academy of Sciences, Beijing, China
- School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, China
| | - Xi Chen
- Institute of Automation, Chinese Academy of Sciences, Beijing, China
- *Correspondence: Xi Chen
| | - Hua Han
- School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
- Institute of Automation, Chinese Academy of Sciences, Beijing, China
- Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
- National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China
- Hua Han
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9
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Mora-Bermúdez F, Huttner WB. What Are the Human-Specific Aspects of Neocortex Development? Front Neurosci 2022; 16:878950. [PMID: 35495057 PMCID: PMC9047014 DOI: 10.3389/fnins.2022.878950] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 03/18/2022] [Indexed: 11/13/2022] Open
Abstract
When considering what makes us human, the development of the neocortex, the seat of our higher cognitive abilities, is of central importance. Throughout this complex developmental process, neocortical stem and progenitor cells (NSPCs) exert a priming role in determining neocortical tissue fate, through a series of cellular and molecular events. In this Perspective article, we address five questions of relevance for potentially human-specific aspects of NSPCs, (i) Are there human-specific NSPC subtypes? (ii) What is the functional significance of the known temporal differences in NSPC dynamics between human and other great apes? (iii) Are there functional interactions between the human-specific genes preferentially expressed in NSPCs? (iv) Do humans amplify certain metabolic pathways for NSPC proliferation? and finally (v) Have differences evolved during human evolution, notably between modern humans and Neandertals, that affect the performance of key genes operating in NSPCs? We discuss potential implications inherent to these questions, and suggest experimental approaches on how to answer them, hoping to provide incentives to further understand key issues of human cortical development.
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10
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Vogl C, Neef J, Wichmann C. Methods for multiscale structural and functional analysis of the mammalian cochlea. Mol Cell Neurosci 2022; 120:103720. [DOI: 10.1016/j.mcn.2022.103720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 02/13/2022] [Accepted: 03/08/2022] [Indexed: 01/11/2023] Open
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Duncan KE, Czymmek KJ, Jiang N, Thies AC, Topp CN. X-ray microscopy enables multiscale high-resolution 3D imaging of plant cells, tissues, and organs. PLANT PHYSIOLOGY 2022; 188:831-845. [PMID: 34618094 PMCID: PMC8825331 DOI: 10.1093/plphys/kiab405] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 07/29/2021] [Indexed: 05/12/2023]
Abstract
Capturing complete internal anatomies of plant organs and tissues within their relevant morphological context remains a key challenge in plant science. While plant growth and development are inherently multiscale, conventional light, fluorescence, and electron microscopy platforms are typically limited to imaging of plant microstructure from small flat samples that lack a direct spatial context to, and represent only a small portion of, the relevant plant macrostructures. We demonstrate technical advances with a lab-based X-ray microscope (XRM) that bridge the imaging gap by providing multiscale high-resolution three-dimensional (3D) volumes of intact plant samples from the cell to the whole plant level. Serial imaging of a single sample is shown to provide sub-micron 3D volumes co-registered with lower magnification scans for explicit contextual reference. High-quality 3D volume data from our enhanced methods facilitate sophisticated and effective computational segmentation. Advances in sample preparation make multimodal correlative imaging workflows possible, where a single resin-embedded plant sample is scanned via XRM to generate a 3D cell-level map, and then used to identify and zoom in on sub-cellular regions of interest for high-resolution scanning electron microscopy. In total, we present the methodologies for use of XRM in the multiscale and multimodal analysis of 3D plant features using numerous economically and scientifically important plant systems.
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Affiliation(s)
- Keith E Duncan
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
| | - Kirk J Czymmek
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
| | - Ni Jiang
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
| | | | - Christopher N Topp
- Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA
- Author for communication:
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12
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Lane R, Wolters AHG, Giepmans BNG, Hoogenboom JP. Integrated Array Tomography for 3D Correlative Light and Electron Microscopy. Front Mol Biosci 2022; 8:822232. [PMID: 35127826 PMCID: PMC8809480 DOI: 10.3389/fmolb.2021.822232] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 12/15/2021] [Indexed: 12/22/2022] Open
Abstract
Volume electron microscopy (EM) of biological systems has grown exponentially in recent years due to innovative large-scale imaging approaches. As a standalone imaging method, however, large-scale EM typically has two major limitations: slow rates of acquisition and the difficulty to provide targeted biological information. We developed a 3D image acquisition and reconstruction pipeline that overcomes both of these limitations by using a widefield fluorescence microscope integrated inside of a scanning electron microscope. The workflow consists of acquiring large field of view fluorescence microscopy (FM) images, which guide to regions of interest for successive EM (integrated correlative light and electron microscopy). High precision EM-FM overlay is achieved using cathodoluminescent markers. We conduct a proof-of-concept of our integrated workflow on immunolabelled serial sections of tissues. Acquisitions are limited to regions containing biological targets, expediting total acquisition times and reducing the burden of excess data by tens or hundreds of GBs.
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Affiliation(s)
- Ryan Lane
- Imaging Physics, Delft University of Technology, Delft, Netherlands
- *Correspondence: Ryan Lane,
| | - Anouk H. G. Wolters
- Department of Biomedical Sciences of Cells and Systems, University Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Ben N. G. Giepmans
- Department of Biomedical Sciences of Cells and Systems, University Groningen, University Medical Center Groningen, Groningen, Netherlands
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Wichmann C, Kuner T. Heterogeneity of glutamatergic synapses: cellular mechanisms and network consequences. Physiol Rev 2022; 102:269-318. [PMID: 34727002 DOI: 10.1152/physrev.00039.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Chemical synapses are commonly known as a structurally and functionally highly diverse class of cell-cell contacts specialized to mediate communication between neurons. They represent the smallest "computational" unit of the brain and are typically divided into excitatory and inhibitory as well as modulatory categories. These categories are subdivided into diverse types, each representing a different structure-function repertoire that in turn are thought to endow neuronal networks with distinct computational properties. The diversity of structure and function found among a given category of synapses is referred to as heterogeneity. The main building blocks for this heterogeneity are synaptic vesicles, the active zone, the synaptic cleft, the postsynaptic density, and glial processes associated with the synapse. Each of these five structural modules entails a distinct repertoire of functions, and their combination specifies the range of functional heterogeneity at mammalian excitatory synapses, which are the focus of this review. We describe synapse heterogeneity that is manifested on different levels of complexity ranging from the cellular morphology of the pre- and postsynaptic cells toward the expression of different protein isoforms at individual release sites. We attempt to define the range of structural building blocks that are used to vary the basic functional repertoire of excitatory synaptic contacts and discuss sources and general mechanisms of synapse heterogeneity. Finally, we explore the possible impact of synapse heterogeneity on neuronal network function.
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Affiliation(s)
- Carolin Wichmann
- Molecular Architecture of Synapses Group, Institute for Auditory Neuroscience, InnerEarLab and Institute for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
| | - Thomas Kuner
- Department of Functional Neuroanatomy, Institute for Anatomy and Cell Biology, Heidelberg, Germany
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14
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Unnersjö-Jess D, Ramdedovic A, Höhne M, Butt L, Koehler FC, Müller RU, Hoyer PF, Blom H, Schermer B, Benzing T. Three-Dimensional Super-Resolved Imaging of Paraffin-Embedded Kidney Samples. KIDNEY360 2021; 3:446-454. [PMID: 35582181 PMCID: PMC9034812 DOI: 10.34067/kid.0005882021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/30/2021] [Indexed: 01/10/2023]
Abstract
Background Diseases of the glomeruli, the renal filtration units, are a leading cause of progressive kidney disease. Assessment of the ultrastructure of podocytes at the glomerular filtration barrier is essential for diagnosing diverse disease entities, providing insight into the disease pathogenesis, and monitoring treatment responses. Methods Here we apply previously published sample preparation methods together with stimulated emission depletion and confocal microscopy for resolving nanoscale podocyte substructure. The protocols are modified and optimized in order to be applied to formalin-fixed paraffin-embedded (FFPE) samples. Results We successfully modified our protocols to allow for deep three-dimensional stimulated emission depletion and confocal imaging of FFPE kidney tissue with similar staining and image quality compared with our previous approaches. We further show that quantitative analysis can be applied to extract morphometrics from healthy and diseased samples from both mice and humans. Conclusions The results from this study could increase the feasibility of implementing optical kidney imaging protocols in clinical routines because FFPE is the gold-standard method for storage of patient samples.
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Affiliation(s)
- David Unnersjö-Jess
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Amer Ramdedovic
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Martin Höhne
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Linus Butt
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Felix C. Koehler
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Roman-Ulrich Müller
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Peter F. Hoyer
- Pediatric Nephrology, Pediatrics II, University of Duisburg-Essen, Essen, Germany
| | - Hans Blom
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Bernhard Schermer
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - Thomas Benzing
- Department II of Internal Medicine and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
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15
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Lewczuk B, Szyryńska N. Field-Emission Scanning Electron Microscope as a Tool for Large-Area and Large-Volume Ultrastructural Studies. Animals (Basel) 2021; 11:ani11123390. [PMID: 34944167 PMCID: PMC8698110 DOI: 10.3390/ani11123390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/24/2021] [Accepted: 11/25/2021] [Indexed: 11/29/2022] Open
Abstract
Simple Summary Ultrastructural studies of cells and tissues are usually performed using transmission electron microscopy (TEM), which enables imaging at the highest possible resolution. The weak point of TEM is the limited ability to analyze the ultrastructure of large areas and volumes of biological samples. This limitation can be overcome by using modern field-emission scanning electron microscopy (FE-SEM) with high-sensitivity detection, which enables the creation of TEM-like images from the flat surfaces of resin-embedded biological specimens. Several FE-SEM-based techniques for two- and three-dimensional ultrastructural studies of cells, tissues, organs, and organisms have been developed in the 21st century. These techniques have created a new era in structural biology and have changed the role of the scanning electron microscope (SEM) in biological and medical laboratories. Since the premiere of the first commercially available SEM in 1965, these instruments were used almost exclusively to obtain topographical information over a large range of magnifications. Currently, FE-SEM offers many attractive possibilities in the studies of cell and tissue ultrastructure, and they are presented in this review. Abstract The development of field-emission scanning electron microscopes for high-resolution imaging at very low acceleration voltages and equipped with highly sensitive detectors of backscattered electrons (BSE) has enabled transmission electron microscopy (TEM)-like imaging of the cut surfaces of tissue blocks, which are impermeable to the electron beam, or tissue sections mounted on the solid substrates. This has resulted in the development of methods that simplify and accelerate ultrastructural studies of large areas and volumes of biological samples. This article provides an overview of these methods, including their advantages and disadvantages. The imaging of large sample areas can be performed using two methods based on the detection of transmitted electrons or BSE. Effective imaging using BSE requires special fixation and en bloc contrasting of samples. BSE imaging has resulted in the development of volume imaging techniques, including array tomography (AT) and serial block-face imaging (SBF-SEM). In AT, serial ultrathin sections are collected manually on a solid substrate such as a glass and silicon wafer or automatically on a tape using a special ultramicrotome. The imaging of serial sections is used to obtain three-dimensional (3D) information. SBF-SEM is based on removing the top layer of a resin-embedded sample using an ultramicrotome inside the SEM specimen chamber and then imaging the exposed surface with a BSE detector. The steps of cutting and imaging the resin block are repeated hundreds or thousands of times to obtain a z-stack for 3D analyses.
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Wu X, Zhang Q, Gong L, He M. Sequencing-Based High-Throughput Neuroanatomy: From Mapseq to Bricseq and Beyond. Neurosci Bull 2021; 37:746-750. [PMID: 33683648 DOI: 10.1007/s12264-021-00646-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 11/06/2020] [Indexed: 12/15/2022] Open
Affiliation(s)
- Xiaoyang Wu
- Department of Neurology, State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Qi Zhang
- Department of Neurology, State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Ling Gong
- Department of Neurology, State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Miao He
- Department of Neurology, State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, 200032, China.
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Abdollahzadeh A, Belevich I, Jokitalo E, Sierra A, Tohka J. DeepACSON automated segmentation of white matter in 3D electron microscopy. Commun Biol 2021; 4:179. [PMID: 33568775 PMCID: PMC7876004 DOI: 10.1038/s42003-021-01699-w] [Citation(s) in RCA: 22] [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: 01/16/2020] [Accepted: 01/12/2021] [Indexed: 01/30/2023] Open
Abstract
Tracing the entirety of ultrastructures in large three-dimensional electron microscopy (3D-EM) images of the brain tissue requires automated segmentation techniques. Current segmentation techniques use deep convolutional neural networks (DCNNs) and rely on high-contrast cellular membranes and high-resolution EM volumes. On the other hand, segmenting low-resolution, large EM volumes requires methods to account for severe membrane discontinuities inescapable. Therefore, we developed DeepACSON, which performs DCNN-based semantic segmentation and shape-decomposition-based instance segmentation. DeepACSON instance segmentation uses the tubularity of myelinated axons and decomposes under-segmented myelinated axons into their constituent axons. We applied DeepACSON to ten EM volumes of rats after sham-operation or traumatic brain injury, segmenting hundreds of thousands of long-span myelinated axons, thousands of cell nuclei, and millions of mitochondria with excellent evaluation scores. DeepACSON quantified the morphology and spatial aspects of white matter ultrastructures, capturing nanoscopic morphological alterations five months after the injury.
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Affiliation(s)
- Ali Abdollahzadeh
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Ilya Belevich
- Electron Microscopy Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Eija Jokitalo
- Electron Microscopy Unit, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Alejandra Sierra
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.
| | - Jussi Tohka
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
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Guo J, Wang G, Tang W, Song D, Wang X, Hong J, Zhang Z. An optimized approach using cryofixation for high-resolution 3D analysis by FIB-SEM. J Struct Biol 2020; 212:107600. [PMID: 32798655 DOI: 10.1016/j.jsb.2020.107600] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 08/07/2020] [Accepted: 08/09/2020] [Indexed: 01/10/2023]
Abstract
Compared with conventional two-dimensional transmission electron microscopy (TEM), focused ion beam scanning electron microscopy (FIB-SEM) can provide more comprehensive 3D information on cell substructures at the nanometer scale. Biological samples prepared by cryofixation using high-pressure freezing demonstrate optimal preservation of the morphology of cellular structures, as these are arrested instantly in their near-native states. However, samples from cryofixation often show a weak back-scatter electron signal and bad image contrast in FIB-SEM imaging. In addition, it is impossible to do large amounts of heavy metal staining. This is commonly achieved via established osmium impregnation (OTO) en bloc staining protocols. Here, we compared the FIB-SEM image quality of brain tissues prepared using several common freeze-substitution media, and we developed an approach that overcomes these limitations through a combination of osmium tetroxide, uranyl acetate, tannic acid, and potassium permanganate at proper concentrations, respectively. Using this optimized sample preparation protocol for high-pressure freezing and freeze-substitution, perfect smooth membrane morphology, even of the lipid bilayers of the cell membrane, was readily obtained using FIB-SEM. In addition, our protocol is broadly applicable and we demonstrated successful application to brain tissues, plant tissues, Caenorhabditis elegans, Candida albicans, and chlorella. This approach combines the potential of cryofixation for 3D large volume analysis of subcellular structures with the high-resolution capabilities of FIB-SEM.
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Affiliation(s)
- Jiansheng Guo
- Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 310058 Hangzhou, Zhejiang, China; Center of Cryo-Electron Microscopy, Zhejiang University School of Medicine, 310058 Hangzhou, Zhejiang, China
| | - Guan Wang
- Department of Neurobiology, Zhejiang University School of Medicine, 310058 Hangzhou, Zhejiang, China
| | - Wen Tang
- Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 310058 Hangzhou, Zhejiang, China
| | - Dandan Song
- Center of Cryo-Electron Microscopy, Zhejiang University School of Medicine, 310058 Hangzhou, Zhejiang, China
| | - Xinqiu Wang
- Institute of Insect Science, Zhejiang University, Hangzhou 310058, China
| | - Jian Hong
- Center of Analysis and Measurement, Zhejiang University, Hangzhou 310029, China
| | - Zhongkai Zhang
- Biotechnology and Genetic Germplasm Resources Research Institute, Yunnan Academy of Agricultural Sciences, Key Lab of Southwestern Crop Gene Resources and Germplasm Innovation Ministry of Agriculture and Rural Affairs, Key Lab of Agricultural Biotechnology of Yunnan Province, Kunming 650205, Yunnan, China.
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Sodium-glucose co-transporter (SGLT) inhibitor restores lost axonal varicosities of the myenteric plexus in a mouse model of high-fat diet-induced obesity. Sci Rep 2020; 10:12372. [PMID: 32704004 PMCID: PMC7378553 DOI: 10.1038/s41598-020-69256-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 07/08/2020] [Indexed: 01/19/2023] Open
Abstract
Diabetes impairs enteric nervous system functions; however, ultrastructural changes underlying the pathophysiology of the myenteric plexus and the effects of sodium-glucose co-transporter (SGLT) inhibitors are poorly understood. This study aimed to investigate three-dimensional ultrastructural changes in axonal varicosities in the myenteric plexus and the effect thereon of the SGLT inhibitor phlorizin in mice fed a high-fat diet (HFD). Three-dimensional ultrastructural analysis using serial block-face imaging revealed that non-treated HFD-fed mice had fewer axonal varicosities and synaptic vesicles in the myenteric plexus than did normal diet-fed control mice. Furthermore, mitochondrial volume was increased and lysosome number decreased in the axons of non-treated HFD-fed mice when compared to those of control mice. Phlorizin treatment restored the axonal varicosities and organelles in HFD-fed mice. Although HFD did not affect the immunolocalisation of PGP9.5, it reduced synaptophysin immunostaining in the myenteric plexus, which was restored by phlorizin treatment. These results suggest that impairment of the axonal varicosities and their synaptic vesicles underlies the damage to the enteric neurons caused by HFD feeding. SGLT inhibitor treatment could restore axonal varicosities and organelles, which may lead to improved gastrointestinal functions in HFD-induced obesity as well as diabetes.
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Kim E, Lee J, Noh S, Kwon O, Mun JY. Double staining method for array tomography using scanning electron microscopy. Appl Microsc 2020; 50:14. [PMID: 33580409 PMCID: PMC7818292 DOI: 10.1186/s42649-020-00033-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 06/05/2020] [Indexed: 11/16/2022] Open
Abstract
Scanning electron microscopy (SEM) plays a central role in analyzing structures by imaging a large area of brain tissue at nanometer scales. A vast amount of data in the large area are required to study structural changes of cellular organelles in a specific cell, such as neurons, astrocytes, oligodendrocytes, and microglia among brain tissue, at sufficient resolution. Array tomography is a useful method for large-area imaging, and the osmium-thiocarbohydrazide-osmium (OTO) and ferrocyanide-reduced osmium methods are commonly used to enhance membrane contrast. Because many samples prepared using the conventional technique without en bloc staining are considered inadequate for array tomography, we suggested an alternative technique using post-staining conventional samples and compared the advantages.
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Affiliation(s)
- Eunjin Kim
- National Instrumentation Center for Environmental Management, Seoul National University, Seoul, South Korea
| | - Jiyoung Lee
- National Instrumentation Center for Environmental Management, Seoul National University, Seoul, South Korea
| | - Seulgi Noh
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu, South Korea.,Neural circuit research group, Korea Brain Research Institute, Daegu, South Korea
| | - Ohkyung Kwon
- National Instrumentation Center for Environmental Management, Seoul National University, Seoul, South Korea.
| | - Ji Young Mun
- Neural circuit research group, Korea Brain Research Institute, Daegu, South Korea.
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Holler M, Ihli J, Tsai EHR, Nudelman F, Verezhak M, van de Berg WDJ, Shahmoradian SH. A lathe system for micrometre-sized cylindrical sample preparation at room and cryogenic temperatures. JOURNAL OF SYNCHROTRON RADIATION 2020; 27:472-476. [PMID: 32153287 PMCID: PMC7064112 DOI: 10.1107/s1600577519017028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 12/19/2019] [Indexed: 05/24/2023]
Abstract
A simple two-spindle based lathe system for the preparation of cylindrical samples intended for X-ray tomography is presented. The setup can operate at room temperature as well as under cryogenic conditions, allowing the preparation of samples down to 20 and 50 µm in diameter, respectively, within minutes. Case studies are presented involving the preparation of a brittle biomineral brachiopod shell and cryogenically fixed soft brain tissue, and their examination by means of ptychographic X-ray computed tomography reveals the preparation method to be mainly free from causing artefacts. Since this lathe system easily yields near-cylindrical samples ideal for tomography, a usage for a wide variety of otherwise challenging specimens is anticipated, in addition to potential use as a time- and cost-saving tool prior to focused ion-beam milling. Fast sample preparation becomes especially important in relation to shorter measurement times expected in next-generation synchrotron sources.
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Affiliation(s)
- Mirko Holler
- Photon Science Division, Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
| | - Johannes Ihli
- Photon Science Division, Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
| | - Esther H. R. Tsai
- Center for Functional Nanomaterials, Brookhaven National Laboratory, New York, NY 11973, USA
| | - Fabio Nudelman
- School of Chemistry, University of Edinburgh, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Mariana Verezhak
- Photon Science Division, Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
| | - Wilma D. J. van de Berg
- Section Clinical Neuroanatomy and Biobanking (CNAB), Department of Anatomy and Neurosciences, Amsterdam UMC, VU University Medical Center, De Boelelaan 1108, Amsterdam 1007, The Netherlands
| | - Sarah H. Shahmoradian
- Photon Science Division, Paul Scherrer Institut, Forschungsstrasse 111, 5232 Villigen PSI, Switzerland
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Goggin P, Ho EML, Gnaegi H, Searle S, Oreffo ROC, Schneider P. Development of protocols for the first serial block-face scanning electron microscopy (SBF SEM) studies of bone tissue. Bone 2020; 131:115107. [PMID: 31669251 PMCID: PMC6961117 DOI: 10.1016/j.bone.2019.115107] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/27/2019] [Accepted: 10/09/2019] [Indexed: 11/28/2022]
Abstract
There is an unmet need for a high-resolution three-dimensional (3D) technique to simultaneously image osteocytes and the matrix in which these cells reside. In serial block-face scanning electron microscopy (SBF SEM), an ultramicrotome mounted within the vacuum chamber of a microscope repeatedly sections a resin-embedded block of tissue. Backscattered electron scans of the block face provide a stack of high-resolution two-dimensional images, which can be used to visualise and quantify cells and organelles in 3D. High-resolution 3D images of biological tissues from SBF SEM have been exploited considerably to date in the neuroscience field. However, non-brain samples, in particular hard biological tissues, have appeared more challenging to image by SBF SEM due to the difficulties of sectioning and rendering the samples conductive. We have developed and propose protocols for bone tissue preparation using SBF SEM, for imaging simultaneously soft and hard bone tissue components in 3D. We review the state of the art in high-resolution imaging of osteocytes, provide a historical perspective of SBF SEM, and we present first SBF SEM proof-of-concept studies for murine and human tissue. The application of SBF SEM to hard tissues will facilitate qualitative and quantitative 3D studies of tissue microstructure and ultrastructure in bone development, ageing and pathologies such as osteoporosis and osteoarthritis.
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Affiliation(s)
- Patricia Goggin
- Bioengineering Science Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Elaine M L Ho
- Bioengineering Science Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | | | | | - Richard O C Oreffo
- Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Philipp Schneider
- Bioengineering Science Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK.
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24
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Saleeba C, Dempsey B, Le S, Goodchild A, McMullan S. A Student's Guide to Neural Circuit Tracing. Front Neurosci 2019; 13:897. [PMID: 31507369 PMCID: PMC6718611 DOI: 10.3389/fnins.2019.00897] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 08/12/2019] [Indexed: 12/17/2022] Open
Abstract
The mammalian nervous system is comprised of a seemingly infinitely complex network of specialized synaptic connections that coordinate the flow of information through it. The field of connectomics seeks to map the structure that underlies brain function at resolutions that range from the ultrastructural, which examines the organization of individual synapses that impinge upon a neuron, to the macroscopic, which examines gross connectivity between large brain regions. At the mesoscopic level, distant and local connections between neuronal populations are identified, providing insights into circuit-level architecture. Although neural tract tracing techniques have been available to experimental neuroscientists for many decades, considerable methodological advances have been made in the last 20 years due to synergies between the fields of molecular biology, virology, microscopy, computer science and genetics. As a consequence, investigators now enjoy an unprecedented toolbox of reagents that can be directed against selected subpopulations of neurons to identify their efferent and afferent connectomes. Unfortunately, the intersectional nature of this progress presents newcomers to the field with a daunting array of technologies that have emerged from disciplines they may not be familiar with. This review outlines the current state of mesoscale connectomic approaches, from data collection to analysis, written for the novice to this field. A brief history of neuroanatomy is followed by an assessment of the techniques used by contemporary neuroscientists to resolve mesoscale organization, such as conventional and viral tracers, and methods of selecting for sub-populations of neurons. We consider some weaknesses and bottlenecks of the most widely used approaches for the analysis and dissemination of tracing data and explore the trajectories that rapidly developing neuroanatomy technologies are likely to take.
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Affiliation(s)
- Christine Saleeba
- Neurobiology of Vital Systems Node, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
- The School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom
| | - Bowen Dempsey
- CNRS, Hindbrain Integrative Neurobiology Laboratory, Neuroscience Paris-Saclay Institute (Neuro-PSI), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Sheng Le
- Neurobiology of Vital Systems Node, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Ann Goodchild
- Neurobiology of Vital Systems Node, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Simon McMullan
- Neurobiology of Vital Systems Node, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
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Schwanke S, Jenssen J, Eipert P, Schmitt O. Towards Differential Connectomics with NeuroVIISAS. Neuroinformatics 2019; 17:163-179. [PMID: 30014279 DOI: 10.1007/s12021-018-9389-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The comparison of connectomes is an essential step to identify changes in structural and functional neuronal networks. However, the connectomes themselves as well as the comparisons of connectomes could be manifold. In most applications, comparisons of connectomes are applied to specific sets of data. In many studies collections of scripts are applied optimized for certain species (non-generic approaches) or diseases (control versus disease group connectomes). These collections of scripts have a limited functionality which do not support functional and topographic mappings of connectomes (hemispherical asymmetries, peripheral nervous system). The platform-independent and generic neuroVIISAS framework is built to circumvent limitations that come with variants of nomenclatures, connectivity lists and connectional hierarchies as well as restrictions to structural connectome analyses. A new analytical module is introduced into the framework to compare different types of connectomes and different representations of the same connectome within a unique software environment. As an example a differential analysis of the partial connectome of the laboratory rat that is based on virus tract tracing with the same regions of non-virus tract tracing has been performed. A relatively large connectional coherence between the two different techniques was found. However, some detected connections are described by virus tract-tracing only.
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Affiliation(s)
- Sebastian Schwanke
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany
| | - Jörg Jenssen
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany
| | - Peter Eipert
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany
| | - Oliver Schmitt
- Department of Anatomy, University of Rostock, Gertrudenstr. 9, 18057, Rostock, Germany.
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Le BD, Stein JL. Mapping causal pathways from genetics to neuropsychiatric disorders using genome-wide imaging genetics: Current status and future directions. Psychiatry Clin Neurosci 2019; 73:357-369. [PMID: 30864184 PMCID: PMC6625892 DOI: 10.1111/pcn.12839] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 02/22/2019] [Accepted: 03/05/2019] [Indexed: 12/17/2022]
Abstract
Imaging genetics aims to identify genetic variants associated with the structure and function of the human brain. Recently, collaborative consortia have been successful in this goal, identifying and replicating common genetic variants influencing gross human brain structure as measured through magnetic resonance imaging. In this review, we contextualize imaging genetic associations as one important link in understanding the causal chain from genetic variant to increased risk for neuropsychiatric disorders. We provide examples in other fields of how identifying genetic variant associations to disease and multiple phenotypes along the causal chain has revealed a mechanistic understanding of disease risk, with implications for how imaging genetics can be similarly applied. We discuss current findings in the imaging genetics research domain, including that common genetic variants can have a slightly larger effect on brain structure than on risk for disorders like schizophrenia, indicating a somewhat simpler genetic architecture. Also, gross brain structure measurements share a genetic basis with some, but not all, neuropsychiatric disorders, invalidating the previously held belief that they are broad endophenotypes, yet pinpointing brain regions likely involved in the pathology of specific disorders. Finally, we suggest that in order to build a more detailed mechanistic understanding of the effects of genetic variants on the brain, future directions in imaging genetics research will require observations of cellular and synaptic structure in specific brain regions beyond the resolution of magnetic resonance imaging. We expect that integrating genetic associations at biological levels from synapse to sulcus will reveal specific causal pathways impacting risk for neuropsychiatric disorders.
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Affiliation(s)
- Brandon D. Le
- Department of Genetics & UNC Neuroscience Center, University of North Carolina at Chapel Hill, USA
| | - Jason L. Stein
- Department of Genetics & UNC Neuroscience Center, University of North Carolina at Chapel Hill, USA
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Eberle AL, Zeidler D. Multi-Beam Scanning Electron Microscopy for High-Throughput Imaging in Connectomics Research. Front Neuroanat 2018; 12:112. [PMID: 30618653 PMCID: PMC6297274 DOI: 10.3389/fnana.2018.00112] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 11/23/2018] [Indexed: 02/06/2023] Open
Abstract
Major progress has been achieved in recent years in three-dimensional microscopy techniques. This applies to the life sciences in general, but specifically the neuroscientific field has been a main driver for developments regarding volume imaging. In particular, scanning electron microscopy offers new insights into the organization of cells and tissues by volume imaging methods, such as serial section array tomography, serial block-face imaging or focused ion beam tomography. However, most of these techniques are restricted to relatively small tissue volumes due to the limited acquisition throughput of most standard imaging techniques. Recently, a novel multi-beam scanning electron microscope technology optimized to the imaging of large sample areas has been developed. Complemented by the commercialization of automated sample preparation robots, the mapping of larger, cubic millimeter range tissue volumes at high-resolution is now within reach. This Mini Review will provide a brief overview of the various approaches to electron microscopic volume imaging, with an emphasis on serial section array tomography and multi-beam scanning electron microscopic imaging.
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Wanner AA, Vishwanathan A. Methods for Mapping Neuronal Activity to Synaptic Connectivity: Lessons From Larval Zebrafish. Front Neural Circuits 2018; 12:89. [PMID: 30410437 PMCID: PMC6209671 DOI: 10.3389/fncir.2018.00089] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 09/28/2018] [Indexed: 12/29/2022] Open
Abstract
For a mechanistic understanding of neuronal circuits in the brain, a detailed description of information flow is necessary. Thereby it is crucial to link neuron function to the underlying circuit structure. Multiphoton calcium imaging is the standard technique to record the activity of hundreds of neurons simultaneously. Similarly, recent advances in high-throughput electron microscopy techniques allow for the reconstruction of synaptic resolution wiring diagrams. These two methods can be combined to study both function and structure in the same specimen. Due to its small size and optical transparency, the larval zebrafish brain is one of the very few vertebrate systems where both, activity and connectivity of all neurons from entire, anatomically defined brain regions, can be analyzed. Here, we describe different methods and the tools required for combining multiphoton microscopy with dense circuit reconstruction from electron microscopy stacks of entire brain regions in the larval zebrafish.
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Affiliation(s)
- Adrian A Wanner
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States
| | - Ashwin Vishwanathan
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States
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Wacker IU, Veith L, Spomer W, Hofmann A, Thaler M, Hillmer S, Gengenbach U, Schröder RR. Multimodal Hierarchical Imaging of Serial Sections for Finding Specific Cellular Targets within Large Volumes. J Vis Exp 2018:57059. [PMID: 29630046 PMCID: PMC5933231 DOI: 10.3791/57059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Targeting specific cells at ultrastructural resolution within a mixed cell population or a tissue can be achieved by hierarchical imaging using a combination of light and electron microscopy. Samples embedded in resin are sectioned into arrays consisting of ribbons of hundreds of ultrathin sections and deposited on pieces of silicon wafer or conductively coated coverslips. Arrays are imaged at low resolution using a digital consumer like smartphone camera or light microscope (LM) for a rapid large area overview, or a wide field fluorescence microscope (fluorescence light microscopy (FLM)) after labeling with fluorophores. After post-staining with heavy metals, arrays are imaged in a scanning electron microscope (SEM). Selection of targets is possible from 3D reconstructions generated by FLM or from 3D reconstructions made from the SEM image stacks at intermediate resolution if no fluorescent markers are available. For ultrastructural analysis, selected targets are finally recorded in the SEM at high-resolution (a few nanometer image pixels). A ribbon-handling tool that can be retrofitted to any ultramicrotome is demonstrated. It helps with array production and substrate removal from the sectioning knife boat. A software platform that allows automated imaging of arrays in the SEM is discussed. Compared to other methods generating large volume EM data, such as serial block-face SEM (SBF-SEM) or focused ion beam SEM (FIB-SEM), this approach has two major advantages: (1) The resin-embedded sample is conserved, albeit in a sliced-up version. It can be stained in different ways and imaged with different resolutions. (2) As the sections can be post-stained, it is not necessary to use samples strongly block-stained with heavy metals to introduce contrast for SEM imaging or render the tissue blocks conductive. This makes the method applicable to a wide variety of materials and biological questions. Particularly prefixed materials e.g., from biopsy banks and pathology labs, can directly be embedded and reconstructed in 3D.
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Affiliation(s)
- Irene U Wacker
- Cryo Electron Microscopy, Centre for Advanced Materials, Universität Heidelberg; Heidelberg Karlsruhe Research Partnership (HEiKA);
| | - Lisa Veith
- Cryo Electron Microscopy, BioQuant, Universitätsklinikum Heidelberg
| | - Waldemar Spomer
- Heidelberg Karlsruhe Research Partnership (HEiKA); Institute for Automation and Applied Computer Science, Karlsruhe Institute of Technology (KIT)
| | - Andreas Hofmann
- Heidelberg Karlsruhe Research Partnership (HEiKA); Institute for Automation and Applied Computer Science, Karlsruhe Institute of Technology (KIT)
| | | | - Stefan Hillmer
- Electron Microscopy Core Facility, Universität Heidelberg
| | - Ulrich Gengenbach
- Heidelberg Karlsruhe Research Partnership (HEiKA); Institute for Automation and Applied Computer Science, Karlsruhe Institute of Technology (KIT)
| | - Rasmus R Schröder
- Cryo Electron Microscopy, Centre for Advanced Materials, Universität Heidelberg; Heidelberg Karlsruhe Research Partnership (HEiKA); Cryo Electron Microscopy, BioQuant, Universitätsklinikum Heidelberg
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Webb RI, Schieber NL. Volume Scanning Electron Microscopy: Serial Block-Face Scanning Electron Microscopy Focussed Ion Beam Scanning Electron Microscopy. BIOLOGICAL AND MEDICAL PHYSICS, BIOMEDICAL ENGINEERING 2018. [DOI: 10.1007/978-3-319-68997-5_5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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31
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Pennacchio FA, Garma LD, Matino L, Santoro F. Bioelectronics goes 3D: new trends in cell–chip interface engineering. J Mater Chem B 2018; 6:7096-7101. [DOI: 10.1039/c8tb01737a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Bioelectronic platforms can be used for electrophysiology, monitoring and stimulating specific cellular functions.
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Affiliation(s)
- F. A. Pennacchio
- Center for Advanced Biomaterials for Healthcare
- Istituto Italiano di Tecnologia
- Naples
- Italy
| | - L. D. Garma
- Center for Advanced Biomaterials for Healthcare
- Istituto Italiano di Tecnologia
- Naples
- Italy
| | - L. Matino
- Center for Advanced Biomaterials for Healthcare
- Istituto Italiano di Tecnologia
- Naples
- Italy
| | - F. Santoro
- Center for Advanced Biomaterials for Healthcare
- Istituto Italiano di Tecnologia
- Naples
- Italy
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32
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Xu CS, Hayworth KJ, Lu Z, Grob P, Hassan AM, García-Cerdán JG, Niyogi KK, Nogales E, Weinberg RJ, Hess HF. Enhanced FIB-SEM systems for large-volume 3D imaging. eLife 2017; 6. [PMID: 28500755 PMCID: PMC5476429 DOI: 10.7554/elife.25916] [Citation(s) in RCA: 204] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 05/09/2017] [Indexed: 12/18/2022] Open
Abstract
Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) can automatically generate 3D images with superior z-axis resolution, yielding data that needs minimal image registration and related post-processing. Obstacles blocking wider adoption of FIB-SEM include slow imaging speed and lack of long-term system stability, which caps the maximum possible acquisition volume. Here, we present techniques that accelerate image acquisition while greatly improving FIB-SEM reliability, allowing the system to operate for months and generating continuously imaged volumes > 106 µm3. These volumes are large enough for connectomics, where the excellent z resolution can help in tracing of small neuronal processes and accelerate the tedious and time-consuming human proofreading effort. Even higher resolution can be achieved on smaller volumes. We present example data sets from mammalian neural tissue, Drosophila brain, and Chlamydomonas reinhardtii to illustrate the power of this novel high-resolution technique to address questions in both connectomics and cell biology. DOI:http://dx.doi.org/10.7554/eLife.25916.001 Precise three-dimensional imaging can help make sense of microscopic details in biology. These images are usually built up from many two-dimensional images stacked on top of each other. One approach for examining particularly fine details, such as the connections between nerve cells in the brain, is called focused ion beam scanning electron microscopy (or FIB-SEM for short). This approach works by creating an image of the surface layer of a sample, which is then stripped away using a beam of charged particles to reveal the layer beneath. The new surface can then be imaged and so on, through the whole sample. Unfortunately, FIB-SEM devices are currently slow and can only run for a short time, leading to a lack of continuity in the stack of images. FIB-SEM would allow faster, more accurate and detailed studies of connections between brain cells, and other elaborate biological systems, if the technology could be made faster and more reliable over months of continuous operation. The current technical challenge is to create a system that can, for example, successfully image and analyse all the connections between the more than 100 thousand cells that make up the brain of a fruit fly – a common model organism in neurobiology. Xu et al. aimed to create a technique to image a complete fly brain, with gaps of just 8 nanometres between each image in a stack, within a reasonable timeframe. By improving how FIB-SEM signals are detected, making use of advances in ion beam controls, and by engineering ways to recover from system malfunctions, Xu et al. developed an enhanced FIB-SEM device. To demonstrate its value, the new technology was used to create images of a third of a fruit fly’s brain, parts of a mouse’s brain, and cells of a single-celled alga called Chlamydomonas reinhardtii. The results show that large and complex samples can be successfully imaged in their entirety to adequate detail, enabling high-quality reconstruction of the connections between nerve cells. The level of detail, which can be further increased for smaller samples, offers advantages in precision and image quality over other comparable techniques. As well as helping to study the brain, this approach could also be used to examine details inside cells. Future work to advance this technology will enable larger and more complete imaging of elaborate biological structures. DOI:http://dx.doi.org/10.7554/eLife.25916.002
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Affiliation(s)
- C Shan Xu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Kenneth J Hayworth
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Zhiyuan Lu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States.,Department of Psychology and Neuroscience, Dalhousie University, Halifax, Canada
| | - Patricia Grob
- Howard Hughes Medical Institute, Molecular and Cell Biology Department, University of California, Berkeley, United States
| | - Ahmed M Hassan
- Howard Hughes Medical Institute, Molecular and Cell Biology Department, University of California, Berkeley, United States
| | - José G García-Cerdán
- Howard Hughes Medical Institute, Plant and Microbial Biology Department, University of California, Berkeley, United States
| | - Krishna K Niyogi
- Howard Hughes Medical Institute, Plant and Microbial Biology Department, University of California, Berkeley, United States.,Lawrence Berkeley National Laboratory, Berkeley, United States
| | - Eva Nogales
- Howard Hughes Medical Institute, Molecular and Cell Biology Department, University of California, Berkeley, United States.,Lawrence Berkeley National Laboratory, Berkeley, United States
| | - Richard J Weinberg
- Department of Cell Biology and Physiology, University of North Carolina, North Carolina, United States
| | - Harald F Hess
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
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Dempsey B, Le S, Turner A, Bokiniec P, Ramadas R, Bjaalie JG, Menuet C, Neve R, Allen AM, Goodchild AK, McMullan S. Mapping and Analysis of the Connectome of Sympathetic Premotor Neurons in the Rostral Ventrolateral Medulla of the Rat Using a Volumetric Brain Atlas. Front Neural Circuits 2017; 11:9. [PMID: 28298886 PMCID: PMC5331070 DOI: 10.3389/fncir.2017.00009] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 02/06/2017] [Indexed: 01/27/2023] Open
Abstract
Spinally projecting neurons in the rostral ventrolateral medulla (RVLM) play a critical role in the generation of vasomotor sympathetic tone and are thought to receive convergent input from neurons at every level of the neuraxis; the factors that determine their ongoing activity remain unresolved. In this study we use a genetically restricted viral tracing strategy to definitively map their spatially diffuse connectome. We infected bulbospinal RVLM neurons with a recombinant rabies variant that drives reporter expression in monosynaptically connected input neurons and mapped their distribution using an MRI-based volumetric atlas and a novel image alignment and visualization tool that efficiently translates the positions of neurons captured in conventional photomicrographs to Cartesian coordinates. We identified prominent inputs from well-established neurohumoral and viscero-sympathetic sensory actuators, medullary autonomic and respiratory subnuclei, and supramedullary autonomic nuclei. The majority of inputs lay within the brainstem (88–94%), and included putative respiratory neurons in the pre-Bötzinger Complex and post-inspiratory complex that are therefore likely to underlie respiratory-sympathetic coupling. We also discovered a substantial and previously unrecognized input from the region immediately ventral to nucleus prepositus hypoglossi. In contrast, RVLM sympathetic premotor neurons were only sparsely innervated by suprapontine structures including the paraventricular nucleus, lateral hypothalamus, periaqueductal gray, and superior colliculus, and we found almost no evidence of direct inputs from the cortex or amygdala. Our approach can be used to quantify, standardize and share complete neuroanatomical datasets, and therefore provides researchers with a platform for presentation, analysis and independent reanalysis of connectomic data.
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Affiliation(s)
- Bowen Dempsey
- Faculty of Medicine and Health Sciences, Neurobiology of Vital Systems, Macquarie University Sydney, NSW, Australia
| | - Sheng Le
- Faculty of Medicine and Health Sciences, Neurobiology of Vital Systems, Macquarie University Sydney, NSW, Australia
| | - Anita Turner
- Faculty of Medicine and Health Sciences, Neurobiology of Vital Systems, Macquarie University Sydney, NSW, Australia
| | - Phil Bokiniec
- Faculty of Medicine and Health Sciences, Neurobiology of Vital Systems, Macquarie University Sydney, NSW, Australia
| | - Radhika Ramadas
- Faculty of Medicine and Health Sciences, Neurobiology of Vital Systems, Macquarie University Sydney, NSW, Australia
| | - Jan G Bjaalie
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo Oslo, Norway
| | - Clement Menuet
- Department of Physiology, University of Melbourne Melbourne, VIC, Australia
| | - Rachael Neve
- Viral Core Facility, McGovern Institute for Brain Research, Massachusetts Institute of Technology Cambridge, MA, USA
| | - Andrew M Allen
- Department of Physiology, University of Melbourne Melbourne, VIC, Australia
| | - Ann K Goodchild
- Faculty of Medicine and Health Sciences, Neurobiology of Vital Systems, Macquarie University Sydney, NSW, Australia
| | - Simon McMullan
- Faculty of Medicine and Health Sciences, Neurobiology of Vital Systems, Macquarie University Sydney, NSW, Australia
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Schieber NL, Machado P, Markert SM, Stigloher C, Schwab Y, Steyer AM. Minimal resin embedding of multicellular specimens for targeted FIB-SEM imaging. Methods Cell Biol 2017; 140:69-83. [DOI: 10.1016/bs.mcb.2017.03.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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35
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Shami GJ, Cheng D, Huynh M, Vreuls C, Wisse E, Braet F. 3-D EM exploration of the hepatic microarchitecture - lessons learned from large-volume in situ serial sectioning. Sci Rep 2016; 6:36744. [PMID: 27834401 PMCID: PMC5105151 DOI: 10.1038/srep36744] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 10/20/2016] [Indexed: 12/12/2022] Open
Abstract
To-date serial block-face scanning electron microscopy (SBF-SEM) dominates as the premier technique for generating three-dimensional (3-D) data of resin-embedded biological samples at an unprecedented depth volume. Given the infancy of the technique, limited literature is currently available regarding the applicability of SBF-SEM for the ultrastructural investigation of tissues. Herein, we provide a comprehensive and rigorous appraisal of five different SBF-SEM sample preparation protocols for the large-volume exploration of the hepatic microarchitecture at an unparalleled X, Y and Z resolution. In so doing, we qualitatively and quantitatively validate the use of a comprehensive SBF-SEM sample preparation protocol, based on the application of heavy metal fixatives, stains and mordanting agents. Employing the best-tested SBF-SEM approach, enabled us to assess large-volume morphometric data on murine parenchymal cells, sinusoids and bile canaliculi. Finally, we integrated the validated SBF-SEM protocol with a correlative light and electron microscopy (CLEM) approach. The combination of confocal scanning laser microscopy and SBF-SEM provided a novel way to picture subcellular detail. We appreciate that this multidimensional approach will aid the subsequent research of liver tissue under relevant experimental and disease conditions.
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Affiliation(s)
- Gerald John Shami
- School of Medical Sciences (Discipline of Anatomy and Histology) – The Bosch Institute, The University of Sydney, NSW 2006, Australia
| | - Delfine Cheng
- School of Medical Sciences (Discipline of Anatomy and Histology) – The Bosch Institute, The University of Sydney, NSW 2006, Australia
| | - Minh Huynh
- Australian Centre for Microscopy and Microanalysis (ACMM), The University of Sydney, NSW 2006, Australia
| | - Celien Vreuls
- Department of Pathology, Amphia Hospital, Breda, The Netherlands
| | - Eddie Wisse
- Australian Centre for Microscopy and Microanalysis (ACMM), The University of Sydney, NSW 2006, Australia
- Maastricht Multimodal Molecular Imaging Institute, Division of Nanoscopy, University of Maastricht, 6200 MD Maastricht, The Netherlands
- Department of Internal Medicine, University of Maastricht, 6200, MD Maastricht, The Netherlands
| | - Filip Braet
- School of Medical Sciences (Discipline of Anatomy and Histology) – The Bosch Institute, The University of Sydney, NSW 2006, Australia
- Australian Centre for Microscopy and Microanalysis (ACMM), The University of Sydney, NSW 2006, Australia
- Cellular Imaging Facility, Charles Perkins Centre, The University of Sydney, NSW 2006, Australia
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36
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Büsse S, Hörnschemeyer T, Fischer C. Three-dimensional reconstruction on cell level: case study elucidates the ultrastructure of the spinning apparatus of Embia sp. (Insecta: Embioptera). ROYAL SOCIETY OPEN SCIENCE 2016; 3:160563. [PMID: 27853574 PMCID: PMC5098999 DOI: 10.1098/rsos.160563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 09/09/2016] [Indexed: 06/06/2023]
Abstract
Spinning is a phenomenon not only present in spiders, but also in many other arthropods. The functional morphology and complexity of spinning organs is often poorly understood. Their elements are minute and studying them poses substantial methodological difficulties. This study presents a three-dimensional reconstruction of a silk gland of Embia sp. on cellular level, based on serial sections acquired with serial block-face scanning electron microscopy (SBFSEM) to showcase the power of this method. Previous studies achieved either high resolution to elucidate the ultrastructure or satisfying three-dimensional representations. The high-resolution achieved by SBFSEM can be easily used to reconstruct the three-dimensional ultrastructural organization of cellular structures. The herein investigated spinning apparatus of Embioptera can be taken as an example demonstrating the potential of this method. It was possible to reconstruct a multinucleated silk gland containing 63 nuclei. We focused on the applicability of this method in the field of morphological research and provide a step-by-step guide to the methodology. This will help in applying the method to other arthropod taxa and will help significantly in adapting the method to other animals, animal parts and tissues.
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Affiliation(s)
- Sebastian Büsse
- Department of Functional Morphology and Biomechanics, Institute of Zoology, Christian-Albrechts-Universität zu Kiel, Am Botanischen Garten 1–9, 24118 Kiel, Germany
- Department of Morphology, Systematics and Evolutionary Biology, J.- F.- Blumenbach Institute for Zoology and Anthropology, Georg-August-Universität Göttingen, Berliner Strasse 28, 37073 Göttingen, Germany
| | - Thomas Hörnschemeyer
- Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325 Frankfurt, Germany
- Department of Morphology, Systematics and Evolutionary Biology, J.- F.- Blumenbach Institute for Zoology and Anthropology, Georg-August-Universität Göttingen, Berliner Strasse 28, 37073 Göttingen, Germany
| | - Christian Fischer
- Department of Morphology, Systematics and Evolutionary Biology, J.- F.- Blumenbach Institute for Zoology and Anthropology, Georg-August-Universität Göttingen, Berliner Strasse 28, 37073 Göttingen, Germany
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37
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Titze B, Genoud C. Volume scanning electron microscopy for imaging biological ultrastructure. Biol Cell 2016; 108:307-323. [DOI: 10.1111/boc.201600024] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 07/13/2016] [Accepted: 07/14/2016] [Indexed: 12/01/2022]
Affiliation(s)
- Benjamin Titze
- Friedrich Miescher Institute for Biomedical Research; Basel Switzerland
| | - Christel Genoud
- Friedrich Miescher Institute for Biomedical Research; Basel Switzerland
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38
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Mikula S. Progress Towards Mammalian Whole-Brain Cellular Connectomics. Front Neuroanat 2016; 10:62. [PMID: 27445704 PMCID: PMC4927572 DOI: 10.3389/fnana.2016.00062] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/26/2016] [Indexed: 11/13/2022] Open
Abstract
Neurons are the fundamental structural units of the nervous system-i.e., the Neuron Doctrine-as the pioneering work of Santiago Ramón y Cajal in the 1880's clearly demonstrated through careful observation of Golgi-stained neuronal morphologies. However, at that time sample preparation, imaging methods and computational tools were either nonexistent or insufficiently developed to permit the precise mapping of an entire brain with all of its neurons and their connections. Some measure of the "mesoscopic" connectional organization of the mammalian brain has been obtained over the past decade by alignment of sparse subsets of labeled neurons onto a reference atlas or via MRI-based diffusion tensor imaging. Neither method, however, provides data on the complete connectivity of all neurons comprising an individual brain. Fortunately, whole-brain cellular connectomics now appears within reach due to recent advances in whole-brain sample preparation and high-throughput electron microscopy (EM), though substantial obstacles remain with respect to large volume electron microscopic acquisitions and automated neurite reconstructions. This perspective examines the current status and problems associated with generating a mammalian whole-brain cellular connectome and argues that the time is right to launch a concerted connectomic attack on a small mammalian whole-brain.
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Affiliation(s)
- Shawn Mikula
- Max-Planck Institute for Neurobiology, Electrons - Photons - NeuronsMartinsried, Germany
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39
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Multiplexed Intact-Tissue Transcriptional Analysis at Cellular Resolution. Cell 2016; 164:792-804. [PMID: 26871636 PMCID: PMC4775740 DOI: 10.1016/j.cell.2016.01.038] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 12/28/2015] [Accepted: 01/25/2016] [Indexed: 12/11/2022]
Abstract
In recently developed approaches for high-resolution imaging within intact tissue, molecular characterization over large volumes has been largely restricted to labeling of proteins. But volumetric nucleic acid labeling may represent a far greater scientific and clinical opportunity, enabling detection of not only diverse coding RNA variants but also non-coding RNAs. Moreover, scaling immunohistochemical detection to large tissue volumes has limitations due to high cost, limited renewability/availability, and restricted multiplexing capability of antibody labels. With the goal of versatile, high-content, and scalable molecular phenotyping of intact tissues, we developed a method using carbodiimide-based chemistry to stably retain RNAs in clarified tissue, coupled with amplification tools for multiplexed detection. The resulting technology enables robust measurement of activity-dependent transcriptional signatures, cell-identity markers, and diverse non-coding RNAs in rodent and human tissue volumes. The growing set of validated probes is deposited in an online resource for nucleating related developments from across the scientific community.
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Tasel SF, Mumcuoglu EU, Hassanpour RZ, Perkins G. A validated active contour method driven by parabolic arc model for detection and segmentation of mitochondria. J Struct Biol 2016; 194:253-71. [PMID: 26956730 DOI: 10.1016/j.jsb.2016.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 02/16/2016] [Accepted: 03/04/2016] [Indexed: 11/19/2022]
Abstract
Recent studies reveal that mitochondria take substantial responsibility in cellular functions that are closely related to aging diseases caused by degeneration of neurons. These studies emphasize that the membrane and crista morphology of a mitochondrion should receive attention in order to investigate the link between mitochondrial function and its physical structure. Electron microscope tomography (EMT) allows analysis of the inner structures of mitochondria by providing highly detailed visual data from large volumes. Computerized segmentation of mitochondria with minimum manual effort is essential to accelerate the study of mitochondrial structure/function relationships. In this work, we improved and extended our previous attempts to detect and segment mitochondria from transmission electron microcopy (TEM) images. A parabolic arc model was utilized to extract membrane structures. Then, curve energy based active contours were employed to obtain roughly outlined candidate mitochondrial regions. Finally, a validation process was applied to obtain the final segmentation data. 3D extension of the algorithm is also presented in this paper. Our method achieved an average F-score performance of 0.84. Average Dice Similarity Coefficient and boundary error were measured as 0.87 and 14nm respectively.
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Affiliation(s)
- Serdar F Tasel
- Department of Health Informatics, Graduate School of Informatics, Middle East Technical University, 06531 Ankara, Turkey; Department of Computer Engineering, Cankaya University, 06810 Ankara, Turkey.
| | - Erkan U Mumcuoglu
- Department of Health Informatics, Graduate School of Informatics, Middle East Technical University, 06531 Ankara, Turkey
| | - Reza Z Hassanpour
- Department of Computer Engineering, Cankaya University, 06810 Ankara, Turkey
| | - Guy Perkins
- National Center for Microscopy and Imaging Research, University of California, San Diego, CA 92093-0608, USA
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42
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Optimizing the 3D-reconstruction technique for serial block-face scanning electron microscopy. J Neurosci Methods 2016; 264:16-24. [PMID: 26928258 DOI: 10.1016/j.jneumeth.2016.02.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 01/18/2016] [Accepted: 02/22/2016] [Indexed: 11/24/2022]
Abstract
BACKGROUND Elucidating the anatomy of neuronal circuits and localizing the synaptic connections between neurons, can give us important insights in how the neuronal circuits work. We are using serial block-face scanning electron microscopy (SBEM) to investigate the anatomy of a collision detection circuit including the Lobula Giant Movement Detector (LGMD) neuron in the locust, Locusta migratoria. For this, thousands of serial electron micrographs are produced that allow us to trace the neuronal branching pattern. NEW METHOD The reconstruction of neurons was previously done manually by drawing cell outlines of each cell in each image separately. This approach was very time consuming and troublesome. To make the process more efficient a new interactive software was developed. It uses the contrast between the neuron under investigation and its surrounding for semi-automatic segmentation. RESULTS For segmentation the user sets starting regions manually and the algorithm automatically selects a volume within the neuron until the edges corresponding to the neuronal outline are reached. Internally the algorithm optimizes a 3D active contour segmentation model formulated as a cost function taking the SEM image edges into account. This reduced the reconstruction time, while staying close to the manual reference segmentation result. COMPARISON WITH EXISTING METHODS Our algorithm is easy to use for a fast segmentation process, unlike previous methods it does not require image training nor an extended computing capacity. CONCLUSION Our semi-automatic segmentation algorithm led to a dramatic reduction in processing time for the 3D-reconstruction of identified neurons.
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Moreau V, Cordelières FP, Poujol C, Sagot I, Saltel F. Meeting report--Imaging the Cell. J Cell Sci 2015; 128:3843-7. [PMID: 26527200 DOI: 10.1242/jcs.180042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Every two years, the French Society for Cell Biology (SBCF) organises an international meeting called 'Imaging the Cell'. This year, the 8th edition was held on 24-26 June 2015 at University of Bordeaux Campus Victoire in the city of Bordeaux, France, a UNESCO World Heritage site. Over the course of three days, the meeting provided a forum for experts in different areas of cell imaging. Its unique approach was to combine conventional oral presentations during morning sessions with practical workshops at hosting institutes and the Bordeaux Imaging Center during the afternoons. The meeting, co-organised by Violaine Moreau and Frédéric Saltel (both INSERM U1053, Bordeaux, France), Christel Poujol and Fabrice Cordelières (both Bordeaux Imaging Center, Bordeaux, France) and Isabelle Sagot (Institut de Biochimie et Génétique Cellulaires, Bordeaux, France), brought together about 120 scientists including 16 outstanding speakers to discuss the latest advances in cell imaging. Thanks to recent progress in imaging technologies, cell biologists are now able to visualise, follow and manipulate cellular processes with unprecedented accuracy. The meeting sessions and workshops highlighted some of the most exciting developments in the field, with sessions dedicated to optogenetics, high-content screening, in vivo and live-cell imaging, correlative light and electron microscopy, as well as super-resolution imaging.
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Affiliation(s)
- Violaine Moreau
- INSERM, U1053, Bordeaux F-33076, France Université de Bordeaux, Bordeaux F-33076, France
| | - Fabrice P Cordelières
- Université de Bordeaux, Bordeaux F-33076, France Bordeaux Imaging Center, UMS 3420 CNRS-Université de Bordeaux-US4 INSERM, Pôle d'imagerie photonique, Bordeaux F-33000, France
| | - Christel Poujol
- Université de Bordeaux, Bordeaux F-33076, France Bordeaux Imaging Center, UMS 3420 CNRS-Université de Bordeaux-US4 INSERM, Pôle d'imagerie photonique, Bordeaux F-33000, France
| | - Isabelle Sagot
- Université de Bordeaux, Bordeaux F-33076, France Institut de Biochimie et Génétique Cellulaires, Bordeaux F-33000, France Centre National de la Recherche Scientifique, UMR5095 Bordeaux, Bordeaux F-33077, France
| | - Frédéric Saltel
- INSERM, U1053, Bordeaux F-33076, France Université de Bordeaux, Bordeaux F-33076, France
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