51
|
Pujals S, Feiner-Gracia N, Delcanale P, Voets I, Albertazzi L. Super-resolution microscopy as a powerful tool to study complex synthetic materials. Nat Rev Chem 2019. [DOI: 10.1038/s41570-018-0070-2] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
52
|
Richter H, Satz AL, Bedoucha M, Buettelmann B, Petersen AC, Harmeier A, Hermosilla R, Hochstrasser R, Burger D, Gsell B, Gasser R, Huber S, Hug MN, Kocer B, Kuhn B, Ritter M, Rudolph MG, Weibel F, Molina-David J, Kim JJ, Santos JV, Stihle M, Georges GJ, Bonfil RD, Fridman R, Uhles S, Moll S, Faul C, Fornoni A, Prunotto M. DNA-Encoded Library-Derived DDR1 Inhibitor Prevents Fibrosis and Renal Function Loss in a Genetic Mouse Model of Alport Syndrome. ACS Chem Biol 2019; 14:37-49. [PMID: 30452219 PMCID: PMC6343110 DOI: 10.1021/acschembio.8b00866] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
The
importance of Discoidin Domain Receptor 1 (DDR1) in renal fibrosis
has been shown via gene knockout and use of antisense oligonucleotides;
however, these techniques act via a reduction of DDR1 protein, while
we prove the therapeutic potential of inhibiting DDR1 phosphorylation
with a small molecule. To date, efforts to generate a selective small-molecule
to specifically modulate the activity of DDR1 in an in vivo model have been unsuccessful. We performed parallel DNA encoded
library screens against DDR1 and DDR2, and discovered a chemical series
that is highly selective for DDR1 over DDR2. Structure-guided optimization
efforts yielded the potent DDR1 inhibitor 2.45, which
possesses excellent kinome selectivity (including 64-fold selectivity
over DDR2 in a biochemical assay), a clean in vitro safety profile, and favorable pharmacokinetic and physicochemical
properties. As desired, compound 2.45 modulates DDR1
phosphorylation in vitro as well as prevents collagen-induced
activation of renal epithelial cells expressing DDR1. Compound 2.45 preserves renal function and reduces tissue damage in Col4a3–/– mice (the preclinical
mouse model of Alport syndrome) when employing a therapeutic dosing
regime, indicating the real therapeutic value of selectively inhibiting
DDR1 phosphorylation in vivo. Our results may have
wider significance as Col4a3–/– mice also represent a model for chronic kidney disease, a disease
which affects 10% of the global population.
Collapse
Affiliation(s)
- Hans Richter
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Alexander L. Satz
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Marc Bedoucha
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Bernd Buettelmann
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Ann C. Petersen
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Anja Harmeier
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Ricardo Hermosilla
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Remo Hochstrasser
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Dominique Burger
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Bernard Gsell
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Rodolfo Gasser
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Sylwia Huber
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Melanie N. Hug
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Buelent Kocer
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Bernd Kuhn
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Martin Ritter
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Markus G. Rudolph
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Franziska Weibel
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
- Ridgeline Therapeutics GmbH, Basel 4070, Switzerland
| | - Judith Molina-David
- Katz Family Division of Nephrology and Hypertension, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
- Peggy and Harold Katz Family Drug Discovery Center, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
| | - Jin-Ju Kim
- Katz Family Division of Nephrology and Hypertension, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
- Peggy and Harold Katz Family Drug Discovery Center, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
| | - Javier Varona Santos
- Katz Family Division of Nephrology and Hypertension, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
- Peggy and Harold Katz Family Drug Discovery Center, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
| | - Martine Stihle
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Guy J. Georges
- Roche Pharma Research and Early Development, Roche Innovation Center, Munich 82377, Germany
| | - R. Daniel Bonfil
- Department of Pathology, College of Medical Sciences, Nova Southeastern University, Fort Lauderdale, Florida 33328, United States
| | - Rafael Fridman
- Department of Pathology, Wayne State University, Detroit, Michigan 48202, United States
| | - Sabine Uhles
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
| | - Solange Moll
- University Hospital of Geneva, 1205 Geneva, Switzerland
| | - Christian Faul
- University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Alessia Fornoni
- Katz Family Division of Nephrology and Hypertension, University of Miami Miller School of Medicine, Miami, Florida 33136, United States
| | - Marco Prunotto
- Roche Pharma Research and Early Development, Roche Innovation Center, Basel 4070, Switzerland
- Office of Innovation, Immunology, Infectious Diseases & Ophthalmology (I2O), Roche and Genentech Late Stage Development, Basel 4070, Switzerland
| |
Collapse
|
53
|
Keeley DP, Sherwood DR. Tissue linkage through adjoining basement membranes: The long and the short term of it. Matrix Biol 2019; 75-76:58-71. [PMID: 29803937 PMCID: PMC6252152 DOI: 10.1016/j.matbio.2018.05.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 05/18/2018] [Accepted: 05/21/2018] [Indexed: 01/01/2023]
Abstract
Basement membranes (BMs) are thin dense sheets of extracellular matrix that surround most tissues. When the BMs of neighboring tissues come into contact, they usually slide along one another and act to separate tissues and organs into distinct compartments. However, in certain specialized regions, the BMs of neighboring tissues link, helping to bring tissues together. These BM connections can be transient, such as during tissue fusion events in development, or long-term, as with adult tissues involved with filtration, including the blood brain barrier and kidney glomerulus. The transitory nature of these connections in development and the complexity of tissue filtration systems in adults have hindered the understanding of how juxtaposed BMs fasten together. The recent identification of a BM-BM adhesion system in C. elegans, termed B-LINK (BM linkage), however, is revealing cellular and extracellular matrix components of a nascent tissue adhesion system. We discuss insights gained from studying the B-LINK tissue adhesion system in C. elegans, compare this adhesion with other BM-BM connections in Drosophila and vertebrates, and outline important future directions towards elucidating this fascinating and poorly understood mode of adhesion that joins neighboring tissues.
Collapse
Affiliation(s)
- Daniel P Keeley
- Department of Biology, Regeneration Next, Duke University, Box 90338, Durham, NC 27708, USA
| | - David R Sherwood
- Department of Biology, Regeneration Next, Duke University, Box 90338, Durham, NC 27708, USA.
| |
Collapse
|
54
|
Funk SD, Lin MH, Miner JH. Alport syndrome and Pierson syndrome: Diseases of the glomerular basement membrane. Matrix Biol 2018; 71-72:250-261. [PMID: 29673759 PMCID: PMC6146048 DOI: 10.1016/j.matbio.2018.04.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/13/2018] [Accepted: 04/13/2018] [Indexed: 12/17/2022]
Abstract
The glomerular basement membrane (GBM) is an important component of the kidney's glomerular filtration barrier. Like all basement membranes, the GBM contains type IV collagen, laminin, nidogen, and heparan sulfate proteoglycan. It is flanked by the podocytes and glomerular endothelial cells that both synthesize it and adhere to it. Mutations that affect the GBM's collagen α3α4α5(IV) components cause Alport syndrome (kidney disease with variable ear and eye defects) and its variants, including thin basement membrane nephropathy. Mutations in LAMB2 that impact the synthesis or function of laminin α5β2γ1 (LM-521) cause Pierson syndrome (congenital nephrotic syndrome with eye and neurological defects) and its less severe variants, including isolated congenital nephrotic syndrome. The very different types of kidney diseases that result from mutations in collagen IV vs. laminin are likely due to very different pathogenic mechanisms. A better understanding of these mechanisms should lead to targeted therapeutic approaches that can help people with these rare but important diseases.
Collapse
Affiliation(s)
- Steven D Funk
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
| |
Collapse
|
55
|
Fabris G, Lucantonio A, Hampe N, Noetzel E, Hoffmann B, DeSimone A, Merkel R. Nanoscale Topography and Poroelastic Properties of Model Tissue Breast Gland Basement Membranes. Biophys J 2018; 115:1770-1782. [PMID: 30322796 DOI: 10.1016/j.bpj.2018.09.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 09/07/2018] [Accepted: 09/10/2018] [Indexed: 01/19/2023] Open
Abstract
Basement membranes (BMs) are thin layers of condensed extracellular matrix proteins serving as permeability filters, cellular anchoring sites, and barriers against cancer cell invasion. It is believed that their biomechanical properties play a crucial role in determining cellular behavior and response, especially in mechanically active tissues like breast glands. Despite this, so far, relatively little attention has been dedicated to their analysis because of the difficulty of isolating and handling such thin layers of material. Here, we isolated BMs derived from MCF10A spheroids-three-dimensional breast gland model systems mimicking in vitro the most relevant phenotypic characteristics of human breast lobules-and characterized them by atomic force microscopy, enhanced resolution confocal microscopy, and scanning electron microscopy. By performing atomic force microscopy height-clamp experiments, we obtained force-relaxation curves that offered the first biomechanical data on isolated breast gland BMs to our knowledge. Based on enhanced resolution confocal microscopy and scanning electron microscopy imaging data, we modeled the system as a polymer network immersed in liquid and described it as a poroelastic material. Finite-element simulations matching the experimental force-relaxation curves allowed for the first quantification, to our knowledge, of the bulk and shear moduli of the membrane as well as its water permeability. These results represent a first step toward a deeper understanding of the mechanism of tensional homeostasis regulating mammary gland activity as well as its disruption during processes of membrane breaching and metastatic invasion.
Collapse
Affiliation(s)
- Gloria Fabris
- Institute of Complex Systems, ICS-7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany; Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, New Jersey
| | | | - Nico Hampe
- Institute of Complex Systems, ICS-7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | - Erik Noetzel
- Institute of Complex Systems, ICS-7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | - Bernd Hoffmann
- Institute of Complex Systems, ICS-7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany
| | | | - Rudolf Merkel
- Institute of Complex Systems, ICS-7: Biomechanics, Forschungszentrum Jülich, Jülich, Germany.
| |
Collapse
|
56
|
Affiliation(s)
- William H Fissell
- Division of Nephrology and Hypertension, Vanderbilt University Medical Center, Nashville, Tennessee; and
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
57
|
Siegerist F, Endlich K, Endlich N. Novel Microscopic Techniques for Podocyte Research. Front Endocrinol (Lausanne) 2018; 9:379. [PMID: 30050501 PMCID: PMC6050355 DOI: 10.3389/fendo.2018.00379] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/22/2018] [Indexed: 01/16/2023] Open
Abstract
Together with endothelial cells and the glomerular basement membrane, podocytes form the size-specific filtration barrier of the glomerulus with their interdigitating foot processes. Since glomerulopathies are associated with so-called foot process effacement-a severe change of well-formed foot processes into flat and broadened processes-visualization of the three-dimensional podocyte morphology is a crucial part for diagnosis of nephrotic diseases. However, interdigitating podocyte foot processes are too narrow to be resolved by classic light microscopy due to Ernst Abbe's law making electron microscopy necessary. Although three dimensional electron microscopy approaches like serial block face and focused ion beam scanning electron microscopy and electron tomography allow volumetric reconstruction of podocytes, these techniques are very time-consuming and too specialized for routine use or screening purposes. During the last few years, different super-resolution microscopic techniques were developed to overcome the optical resolution limit enabling new insights into podocyte morphology. Super-resolution microscopy approaches like three dimensional structured illumination microscopy (3D-SIM), stimulated emission depletion microscopy (STED) and localization microscopy [stochastic optical reconstruction microscopy (STORM), photoactivated localization microscopy (PALM)] reach resolutions down to 80-20 nm and can be used to image and further quantify podocyte foot process morphology. Furthermore, in vivo imaging of podocytes is essential to study the behavior of these cells in situ. Therefore, multiphoton laser microscopy was a breakthrough for in vivo studies of podocytes in transgenic animal models like rodents and zebrafish larvae because it allows imaging structures up to several hundred micrometer in depth within the tissue. Additionally, along with multiphoton microscopy, lightsheet microscopy is currently used to visualize larger tissue volumes and therefore image complete glomeruli in their native tissue context. Alongside plain visualization of cellular structures, atomic force microscopy has been used to study the change of mechanical properties of podocytes in diseased states which has been shown to be a culprit in podocyte maintenance. This review discusses recent advances in the field of microscopic imaging and demonstrates their currently used and other possible applications for podocyte research.
Collapse
Affiliation(s)
| | | | - Nicole Endlich
- Institute for Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| |
Collapse
|
58
|
Chozinski TJ, Mao C, Halpern AR, Pippin JW, Shankland SJ, Alpers CE, Najafian B, Vaughan JC. Volumetric, Nanoscale Optical Imaging of Mouse and Human Kidney via Expansion Microscopy. Sci Rep 2018; 8:10396. [PMID: 29991751 PMCID: PMC6039510 DOI: 10.1038/s41598-018-28694-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 06/21/2018] [Indexed: 01/19/2023] Open
Abstract
Although light microscopy is a powerful tool for the assessment of kidney physiology and pathology, it has traditionally been unable to resolve structures separated by less than the ~250 nm diffraction limit of visible light. Here, we report on the optimization, validation, and application of a recently developed super-resolution fluorescence microscopy method, called expansion microscopy (ExM), for volumetric interrogation of mouse and human kidney tissue with 70-75 nm lateral and ~250 nm axial spatial resolution. Using ExM with a standard confocal microscope, we resolve fine details of structures that have traditionally required visualization by electron microscopy, including podocyte foot processes, the glomerular basement membrane, and the cytoskeleton. This inexpensive and accessible approach to volumetric, nanoscale imaging enables visualization of fine structural details of kidney tissues that were previously difficult or impossible to measure by conventional methodologies.
Collapse
Affiliation(s)
- Tyler J Chozinski
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA
| | - Chenyi Mao
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA
| | - Aaron R Halpern
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA
| | - Jeffrey W Pippin
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, Washington, 98195, USA
| | - Stuart J Shankland
- Department of Medicine, Division of Nephrology, University of Washington, Seattle, Washington, 98195, USA
| | - Charles E Alpers
- Department of Pathology, University of Washington, Seattle, Washington, 98195, USA
| | - Behzad Najafian
- Department of Pathology, University of Washington, Seattle, Washington, 98195, USA
| | - Joshua C Vaughan
- Department of Chemistry, University of Washington, Seattle, Washington, 98195, USA.
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington, 98195, USA.
| |
Collapse
|
59
|
van Elsland DM, Pujals S, Bakkum T, Bos E, Oikonomeas‐Koppasis N, Berlin I, Neefjes J, Meijer AH, Koster AJ, Albertazzi L, van Kasteren SI. Ultrastructural Imaging of Salmonella-Host Interactions Using Super-resolution Correlative Light-Electron Microscopy of Bioorthogonal Pathogens. Chembiochem 2018; 19:1766-1770. [PMID: 29869826 PMCID: PMC6120560 DOI: 10.1002/cbic.201800230] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Indexed: 01/06/2023]
Abstract
The imaging of intracellular pathogens inside host cells is complicated by the low resolution and sensitivity of fluorescence microscopy and by the lack of ultrastructural information to visualize the pathogens. Herein, we present a new method to visualize these pathogens during infection that circumvents these problems: by using a metabolic hijacking approach to bioorthogonally label the intracellular pathogen Salmonella Typhimurium and by using these bioorthogonal groups to introduce fluorophores compatible with stochastic optical reconstruction microscopy (STORM) and placing this in a correlative light electron microscopy (CLEM) workflow, the pathogen can be imaged within its host cell context Typhimurium with a resolution of 20 nm. This STORM-CLEM approach thus presents a new approach to understand these pathogens during infection.
Collapse
Affiliation(s)
- Daphne M. van Elsland
- Leiden Institute of Chemistry andThe Institute for Chemical ImmunologyLeiden UniversityEinsteinweg 55, 2333CCLeidenThe Netherlands
- Department of Cell and Chemical BiologyInstitute for Chemical ImmunologyLeiden University Medical Center LUMCEinthovenweg 222333 ZCLeidenThe Netherlands
| | - Sílvia Pujals
- Department of Nanoscopy for NanomedicineInstitute of Bioengineering of Catalonia (IBEC)Barcelona Institute of Science and Technology08028BarcelonaSpain
| | - Thomas Bakkum
- Leiden Institute of Chemistry andThe Institute for Chemical ImmunologyLeiden UniversityEinsteinweg 55, 2333CCLeidenThe Netherlands
| | - Erik Bos
- Department of Electron MicroscopyLeiden University Medical Center LUMCEinthovenweg 222333 ZCLeidenThe Netherlands
| | - Nikolaos Oikonomeas‐Koppasis
- Leiden Institute of Chemistry andThe Institute for Chemical ImmunologyLeiden UniversityEinsteinweg 55, 2333CCLeidenThe Netherlands
| | - Ilana Berlin
- Department of Cell and Chemical BiologyInstitute for Chemical ImmunologyLeiden University Medical Center LUMCEinthovenweg 222333 ZCLeidenThe Netherlands
| | - Jacques Neefjes
- Department of Cell and Chemical BiologyInstitute for Chemical ImmunologyLeiden University Medical Center LUMCEinthovenweg 222333 ZCLeidenThe Netherlands
| | - Annemarie H. Meijer
- Institute of Biology LeidenLeiden UniversitySylviusweg 722333 BELeidenThe Netherlands
| | - Abraham J. Koster
- Department of Electron MicroscopyLeiden University Medical Center LUMCEinthovenweg 222333 ZCLeidenThe Netherlands
| | - Lorenzo Albertazzi
- Department of Nanoscopy for NanomedicineInstitute of Bioengineering of Catalonia (IBEC)Barcelona Institute of Science and Technology08028BarcelonaSpain
- Department of Biomedical Engineering and Institute of Complex Molecular SystemsEindhoven University of Technology5600 MBEindhovenThe Netherlands
| | - Sander I. van Kasteren
- Leiden Institute of Chemistry andThe Institute for Chemical ImmunologyLeiden UniversityEinsteinweg 55, 2333CCLeidenThe Netherlands
| |
Collapse
|
60
|
Affiliation(s)
- Alda Tufro
- Departments of Pediatrics and Cell and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut
| |
Collapse
|
61
|
Lin MH, Miller JB, Kikkawa Y, Suleiman HY, Tryggvason K, Hodges BL, Miner JH. Laminin-521 Protein Therapy for Glomerular Basement Membrane and Podocyte Abnormalities in a Model of Pierson Syndrome. J Am Soc Nephrol 2018; 29:1426-1436. [PMID: 29472414 PMCID: PMC5967757 DOI: 10.1681/asn.2017060690] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 01/14/2018] [Indexed: 12/22/2022] Open
Abstract
Background Laminin α5β2γ1 (LM-521) is a major component of the GBM. Mutations in LAMB2 that prevent LM-521 synthesis and/or secretion cause Pierson syndrome, a rare congenital nephrotic syndrome with diffuse mesangial sclerosis and ocular and neurologic defects. Because the GBM is uniquely accessible to plasma, which permeates endothelial cell fenestrae, we hypothesized that intravenous delivery of LM-521 could replace the missing LM-521 in the GBM of Lamb2 mutant mice and restore glomerular permselectivity.Methods We injected human LM-521 (hLM-521), a macromolecule of approximately 800 kD, into the retro-orbital sinus of Lamb2-/- pups daily. Deposition of hLM-521 into the GBM was investigated by fluorescence microscopy. We assayed the effects of hLM-521 on glomerular permselectivity by urinalysis and the effects on podocytes by desmin immunostaining and ultrastructural analysis of podocyte architecture.Results Injected hLM-521 rapidly and stably accumulated in the GBM of all glomeruli. Super-resolution imaging showed that hLM-521 accumulated in the correct orientation in the GBM, primarily on the endothelial aspect. Treatment with hLM-521 greatly reduced the expression of the podocyte injury marker desmin and attenuated the foot process effacement observed in untreated pups. Moreover, treatment with hLM-521 delayed the onset of proteinuria but did not prevent nephrotic syndrome, perhaps due to its absence from the podocyte aspect of the GBM.Conclusions These studies show that GBM composition and function can be altered in vivovia vascular delivery of even very large proteins, which may advance therapeutic options for patients with abnormal GBM composition, whether genetic or acquired.
Collapse
Affiliation(s)
- Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Joseph B Miller
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Yamato Kikkawa
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Karl Tryggvason
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden; and
| | | | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri;
| |
Collapse
|
62
|
Omachi K, Kamura M, Teramoto K, Kojima H, Yokota T, Kaseda S, Kuwazuru J, Fukuda R, Koyama K, Matsuyama S, Motomura K, Shuto T, Suico MA, Kai H. A Split-Luciferase-Based Trimer Formation Assay as a High-throughput Screening Platform for Therapeutics in Alport Syndrome. Cell Chem Biol 2018. [PMID: 29526710 DOI: 10.1016/j.chembiol.2018.02.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Alport syndrome is a hereditary glomerular disease caused by mutation in type IV collagen α3-α5 chains (α3-α5(IV)), which disrupts trimerization, leading to glomerular basement membrane degeneration. Correcting the trimerization of α3/α4/α5 chain is a feasible therapeutic approach, but is hindered by lack of information on the regulation of intracellular α(IV) chain and the absence of high-throughput screening (HTS) platforms to assess α345(IV) trimer formation. Here, we developed sets of split NanoLuc-fusion α345(IV) proteins to monitor α345(IV) trimerization of wild-type and clinically associated mutant α5(IV). The α345(IV) trimer assay, which satisfied the acceptance criteria for HTS, enabled the characterization of intracellular- and secretion-dependent defects of mutant α5(IV). Small interfering RNA-based and chemical screening targeting the ER identified several chemical chaperones that have potential to promote α345(IV) trimer formation. This split luciferase-based trimer formation assay is a functional HTS platform that realizes the feasibility of targeting α345(IV) trimers to treat Alport syndrome.
Collapse
Affiliation(s)
- Kohei Omachi
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Misato Kamura
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Keisuke Teramoto
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Haruka Kojima
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Tsubasa Yokota
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Shota Kaseda
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Jun Kuwazuru
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Ryosuke Fukuda
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Kosuke Koyama
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Shingo Matsuyama
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Keishi Motomura
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Tsuyoshi Shuto
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Mary Ann Suico
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan.
| | - Hirofumi Kai
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan.
| |
Collapse
|
63
|
Saitoh S, Ohno N, Saitoh Y, Terada N, Shimo S, Aida K, Fujii H, Kobayashi T, Ohno S. Improved Serial Sectioning Techniques for Correlative Light-Electron Microscopy Mapping of Human Langerhans Islets. Acta Histochem Cytochem 2018; 51:9-20. [PMID: 29622846 PMCID: PMC5880804 DOI: 10.1267/ahc.17020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 11/29/2017] [Indexed: 01/19/2023] Open
Abstract
Combined analysis of immunostaining for various biological molecules coupled with investigations of ultrastructural features of individual cells is a powerful approach for studies of cellular functions in normal and pathological conditions. However, weak antigenicity of tissues fixed by conventional methods poses a problem for immunoassays. This study introduces a method of correlative light and electron microscopy imaging of the same endocrine cells of compact and diffuse islets from human pancreatic tissue specimens. The method utilizes serial sections obtained from Epon-embedded specimens fixed with glutaraldehyde and osmium tetroxide. Double-immunofluorescence staining of thick Epon sections for endocrine hormones (insulin and glucagon) and regenerating islet-derived gene 1 α (REG1α) was performed following the removal of Epoxy resin with sodium ethoxide, antigen retrieval by autoclaving, and de-osmification treatment with hydrogen peroxide. The immunofluorescence images of endocrine cells were superimposed with the electron microscopy images of the same cells obtained from serial ultrathin sections. Immunofluorescence images showed well-preserved secretory granules in endocrine cells, whereas electron microscopy observations demonstrated corresponding secretory granules and intracellular organelles in the same cells. In conclusion, the correlative imaging approach developed by us may be useful for examining ultrastructural features in combination with immunolocalisation of endocrine hormones in the same human pancreatic islets.
Collapse
Affiliation(s)
- Sei Saitoh
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
- Present address: Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences
| | - Nobuhiko Ohno
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Yurika Saitoh
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Nobuo Terada
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
- Department of Occupational Therapy, School of Health Sciences, Shinshu University School of Medicine
| | - Satoshi Shimo
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Kaoru Aida
- Third Department of Internal Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Hideki Fujii
- First Department of Surgery, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Tetsuro Kobayashi
- Third Department of Internal Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Shinichi Ohno
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| |
Collapse
|
64
|
Chakraborty S, Hong W. Linking Extracellular Matrix Agrin to the Hippo Pathway in Liver Cancer and Beyond. Cancers (Basel) 2018; 10:cancers10020045. [PMID: 29415512 PMCID: PMC5836077 DOI: 10.3390/cancers10020045] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 02/05/2018] [Accepted: 02/05/2018] [Indexed: 12/14/2022] Open
Abstract
In addition to the structural and scaffolding role, the extracellular matrix (ECM) is emerging as a hub for biomechanical signal transduction that is frequently relayed to intracellular sensors to regulate diverse cellular processes. At a macroscopic scale, matrix rigidity confers long-ranging effects contributing towards tissue fibrosis and cancer. The transcriptional co-activators YAP/TAZ, better known as the converging effectors of the Hippo pathway, are widely recognized for their new role as nuclear mechanosensors during organ homeostasis and cancer. Still, how YAP/TAZ senses these “stiffness cues” from the ECM remains enigmatic. Here, we highlight the recent perspectives on the role of agrin in mechanosignaling from the ECM via antagonizing the Hippo pathway to activate YAP/TAZ in the contexts of cancer, neuromuscular junctions, and cardiac regeneration.
Collapse
Affiliation(s)
- Sayan Chakraborty
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A-STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore.
| | - Wanjin Hong
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A-STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore.
| |
Collapse
|
65
|
Maselli RA, Arredondo J, Vázquez J, Chong JX, Bamshad MJ, Nickerson DA, Lara M, Ng F, Lo VL, Pytel P, McDonald CM. A presynaptic congenital myasthenic syndrome attributed to a homozygous sequence variant in LAMA5. Ann N Y Acad Sci 2018; 1413:119-125. [PMID: 29377152 DOI: 10.1111/nyas.13585] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 11/18/2017] [Accepted: 11/27/2017] [Indexed: 12/23/2022]
Abstract
We report a severe defect of neuromuscular transmission in a consanguineous patient with a homozygous variant in the laminin α5 subunit gene (LAMA5). The variant c.8046C > T (p.Arg2659Trp) is rare and has a predicted deleterious effect. The affected individual, who also carries a rare homozygous sequence variant in LAMA1, had normal cognitive function, but magnetic resonance brain imaging showed mild volume loss and periventricular T2 prolongation. Repetitive nerve stimulation at 2 Hz showed 50% decrement of compound muscle action potential amplitudes but 250% facilitation immediately after exercise, similar to that seen in Lambert-Eaton myasthenic syndrome. Endplate studies demonstrated a profound reduction of the endplate potential quantal content but normal amplitudes of miniature endplate potentials. Electron microscopy showed endplates with increased postsynaptic folding that were denuded or only partially occupied by small nerve terminals. Expression studies revealed that p.Arg2659Trp caused decreased binding of laminin α5 to SV2A and impaired laminin-521 cell adhesion and cell projection support in primary neuronal cultures. In summary, this report describing severe neuromuscular transmission failure in a patient with a LAMA5 mutation expands the list of phenotypes associated with defects in genes encoding α-laminins.
Collapse
Affiliation(s)
- Ricardo A Maselli
- Department of Neurology, University of California Davis, Sacramento, California
| | - Juan Arredondo
- Department of Neurology, University of California Davis, Sacramento, California
| | - Jessica Vázquez
- Department of Neurology, University of California Davis, Sacramento, California
| | - Jessica X Chong
- Department of Pediatrics, University of Washington, Seattle, Washington
| | - Michael J Bamshad
- Department of Pediatrics, University of Washington, Seattle, Washington.,Department of Genome Sciences, University of Washington, Seattle, Washington.,Division of Genetic Medicine, Seattle Children's Hospital, Seattle, Washington
| | - Deborah A Nickerson
- Department of Genome Sciences, University of Washington, Seattle, Washington
| | - Marian Lara
- Department of Neurology, University of California Davis, Sacramento, California
| | - Fiona Ng
- Department of Neurology, University of California Davis, Sacramento, California
| | - Victoria Lee Lo
- Department of Neurology, University of California Davis, Sacramento, California
| | - Peter Pytel
- Department of Pathology, University of Chicago, Chicago, Illinois
| | - Craig M McDonald
- Department of Medicine and Rehabilitation, University of California Davis, Sacramento, California
| |
Collapse
|
66
|
Abstract
The glomerular basement membrane (GBM) is a specialized structure with a significant role in maintaining the glomerular filtration barrier. This GBM is formed from the fusion of two basement membranes during development and its function in the filtration barrier is achieved by key extracellular matrix components including type IV collagen, laminins, nidogens, and heparan sulfate proteoglycans. The characteristics of specific matrix isoforms such as laminin-521 (α5β2γ1) and the α3α4α5 chain of type IV collagen are essential for the formation of a mature GBM and the restricted tissue distribution of these isoforms makes the GBM a unique structure. Detailed investigation of the GBM has been driven by the identification of inherited abnormalities in matrix proteins and the need to understand pathogenic mechanisms causing severe glomerular disease. A well-described hereditary GBM disease is Alport syndrome, associated with a progressive glomerular disease, hearing loss, and lens defects due to mutations in the genes COL4A3, COL4A4, or COL4A5. Other proteins associated with inherited diseases of the GBM include laminin β2 in Pierson syndrome and LMX1B in nail patella syndrome. The knowledge of these genetic mutations associated with GBM defects has enhanced our understanding of cell-matrix signaling pathways affected in glomerular disease. This review will address current knowledge of GBM-associated abnormalities and related signaling pathways, as well as discussing the advances toward disease-targeted therapies for patients with glomerular disease.
Collapse
Affiliation(s)
- Christine Chew
- Faculty of Biology Medicine and Health, Wellcome Trust Centre for Cell-Matrix Research, Division of Cell Matrix Biology, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Rachel Lennon
- Faculty of Biology Medicine and Health, Wellcome Trust Centre for Cell-Matrix Research, Division of Cell Matrix Biology, School of Biological Sciences, University of Manchester, Manchester, United Kingdom.,Department of Paediatric Nephrology, Royal Manchester Children's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| |
Collapse
|
67
|
Hoess P, Mund M, Reitberger M, Ries J. Dual-Color and 3D Super-Resolution Microscopy of Multi-protein Assemblies. Methods Mol Biol 2018; 1764:237-251. [PMID: 29605918 DOI: 10.1007/978-1-4939-7759-8_14] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
Breaking the resolution limit of conventional microscopy by super-resolution microscopy (SRM) led to many new biological insights into protein assemblies at the nanoscale. Here we provide detailed protocols for single-molecule localization microscopy (SMLM) to image the structure of a protein complex. As examples, we show how to acquire single- and dual-color super-resolution images of the nuclear pore complex (NPC) and dual-color 3D data on actin and paxillin in focal adhesions.
Collapse
Affiliation(s)
- Philipp Hoess
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Markus Mund
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Manuel Reitberger
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Jonas Ries
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
| |
Collapse
|
68
|
Perry G, Xiao W, Welsh GI, Perriman AW, Lennon R. Engineered basement membranes: from in vivo considerations to cell-based assays. Integr Biol (Camb) 2018; 10:680-695. [DOI: 10.1039/c8ib00138c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Engineered basement membranes are required to mimic in vivo properties within cell-based assays.
Collapse
Affiliation(s)
- Guillaume Perry
- Sorbonne Université, Laboratoire d’Electronique et d’Electromagnétisme
- F-75005 Paris
- France
| | - Wenjin Xiao
- School of Cellular and Molecular Medicine, University of Bristol
- BS8 1TD Bristol
- UK
| | - Gavin I. Welsh
- Bristol Renal, Bristol Medical School, University of Bristol
- BS1 3NY Bristol
- UK
| | - Adam W. Perriman
- School of Cellular and Molecular Medicine, University of Bristol
- BS8 1TD Bristol
- UK
| | - Rachel Lennon
- Wellcome Trust Centre for Cell Matrix Research, Faculty of Biology, Medicine and Health, University of Manchester
- M13 9PT Manchester
- UK
| |
Collapse
|
69
|
Funk SD, Bayer RH, Malone AF, McKee KK, Yurchenco PD, Miner JH. Pathogenicity of a Human Laminin β2 Mutation Revealed in Models of Alport Syndrome. J Am Soc Nephrol 2017; 29:949-960. [PMID: 29263159 DOI: 10.1681/asn.2017090997] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Accepted: 11/19/2017] [Indexed: 01/15/2023] Open
Abstract
Pierson syndrome is a congenital nephrotic syndrome with eye and neurologic defects caused by mutations in laminin β2 (LAMB2), a major component of the glomerular basement membrane (GBM). Pathogenic missense mutations in human LAMB2 cluster in or near the laminin amino-terminal (LN) domain, a domain required for extracellular polymerization of laminin trimers and basement membrane scaffolding. Here, we investigated an LN domain missense mutation, LAMB2-S80R, which was discovered in a patient with Pierson syndrome and unusually late onset of proteinuria. Biochemical data indicated that this mutation impairs laminin polymerization, which we hypothesized to be the cause of the patient's nephrotic syndrome. Testing this hypothesis in genetically altered mice showed that the corresponding amino acid change (LAMB2-S83R) alone is not pathogenic. However, expression of LAMB2-S83R significantly increased the rate of progression to kidney failure in a Col4a3-/- mouse model of autosomal recessive Alport syndrome and increased proteinuria in Col4a5+/- females that exhibit a mild form of X-linked Alport syndrome due to mosaic deposition of collagen α3α4α5(IV) in the GBM. Collectively, these data show the pathogenicity of LAMB2-S80R and provide the first evidence of genetic modification of Alport phenotypes by variation in another GBM component. This finding could help explain the wide range of Alport syndrome onset and severity observed in patients with Alport syndrome, even for family members who share the same COL4 mutation. Our results also show the complexities of using model organisms to investigate genetic variants suspected of being pathogenic in humans.
Collapse
Affiliation(s)
- Steven D Funk
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Raymond H Bayer
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Andrew F Malone
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| |
Collapse
|
70
|
Unnersjö-Jess D, Scott L, Sevilla SZ, Patrakka J, Blom H, Brismar H. Confocal super-resolution imaging of the glomerular filtration barrier enabled by tissue expansion. Kidney Int 2017; 93:1008-1013. [PMID: 29241621 DOI: 10.1016/j.kint.2017.09.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 08/17/2017] [Accepted: 09/07/2017] [Indexed: 11/24/2022]
Abstract
The glomerular filtration barrier, has historically only been spatially resolved using electron microscopy due to the nanometer-scale dimensions of these structures. Recently, it was shown that the nanoscale distribution of proteins in the slit diaphragm can be resolved by fluorescence based stimulated emission depletion microscopy, in combination with optical clearing. Fluorescence microscopy has advantages over electron microscopy in terms of multiplex imaging of different epitopes, and also the amount of volumetric data that can be extracted from thicker samples. However, stimulated emission depletion microscopy is still a costly technique commonly not available to most life science researchers. An imaging technique with which the glomerular filtration barrier can be visualized using more standard fluorescence imaging techniques is thus desirable. Recent studies have shown that biological tissue samples can be isotropically expanded, revealing nanoscale localizations of multiple epitopes using confocal microscopy. Here we show that kidney samples can be expanded sufficiently to study the finest elements of the filtration barrier using confocal microscopy. Thus, our result opens up the possibility to study protein distributions and foot process morphology on the effective nanometer-scale.
Collapse
Affiliation(s)
- David Unnersjö-Jess
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Lena Scott
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Sonia Zambrano Sevilla
- KI/AZ Integrated CardioMetabolic Center, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Jaakko Patrakka
- KI/AZ Integrated CardioMetabolic Center, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Hans Blom
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden; Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden.
| |
Collapse
|
71
|
Mateos JM, Barmettler G, Doehner J, Ojeda Naharros I, Guhl B, Neuhauss SCF, Kaech A, Bachmann-Gagescu R, Ziegler U. Correlative Super-resolution and Electron Microscopy to Resolve Protein Localization in Zebrafish Retina. J Vis Exp 2017. [PMID: 29155784 PMCID: PMC5755354 DOI: 10.3791/56113] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We present a method to investigate the subcellular protein localization in the larval zebrafish retina by combining super-resolution light microscopy and scanning electron microscopy. The sub-diffraction limit resolution capabilities of super-resolution light microscopes allow improving the accuracy of the correlated data. Briefly, 110 nanometer thick cryo-sections are transferred to a silicon wafer and, after immunofluorescence staining, are imaged by super-resolution light microscopy. Subsequently, the sections are preserved in methylcellulose and platinum shadowed prior to imaging in a scanning electron microscope (SEM). The images from these two microscopy modalities are easily merged using tissue landmarks with open source software. Here we describe the adapted method for the larval zebrafish retina. However, this method is also applicable to other types of tissues and organisms. We demonstrate that the complementary information obtained by this correlation is able to resolve the expression of mitochondrial proteins in relation with the membranes and cristae of mitochondria as well as to other compartments of the cell.
Collapse
Affiliation(s)
- José M Mateos
- Center for Microscopy and Image Analysis, University of Zurich;
| | - Gery Barmettler
- Center for Microscopy and Image Analysis, University of Zurich
| | - Jana Doehner
- Center for Microscopy and Image Analysis, University of Zurich
| | | | - Bruno Guhl
- Center for Microscopy and Image Analysis, University of Zurich
| | | | - Andres Kaech
- Center for Microscopy and Image Analysis, University of Zurich
| | - Ruxandra Bachmann-Gagescu
- Institute for Molecular Life Sciences, University of Zurich; Institute for Medical Genetics, University of Zurich
| | - Urs Ziegler
- Center for Microscopy and Image Analysis, University of Zurich
| |
Collapse
|
72
|
Abstract
Using a mouse model of Alport disease, Dufek et al. report that endothelial cell-derived endothelin-1 activates mesangial cells, which deposit abnormal laminin isoforms in the Alport glomerular basement membrane. This study extends findings obtained previously by this laboratory implicating mesangial cells in the early pathogenesis of Alport disease. Together with abnormalities in matrix receptor expression, cytoskeletal architecture, and proteinase secretion in podocytes, a clearer picture is emerging on the inception of proteinuria in Alport disease.
Collapse
|
73
|
Zhang D, Lee J, Kilian KA. Synthetic Biomaterials to Rival Nature's Complexity-a Path Forward with Combinatorics, High-Throughput Discovery, and High-Content Analysis. Adv Healthc Mater 2017; 6. [PMID: 28841770 DOI: 10.1002/adhm.201700535] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/08/2017] [Indexed: 12/18/2022]
Abstract
Cells in tissue receive a host of soluble and insoluble signals in a context-dependent fashion, where integration of these cues through a complex network of signal transduction cascades will define a particular outcome. Biomaterials scientists and engineers are tasked with designing materials that can at least partially recreate this complex signaling milieu towards new materials for biomedical applications. In this progress report, recent advances in high throughput techniques and high content imaging approaches that are facilitating the discovery of efficacious biomaterials are described. From microarrays of synthetic polymers, peptides and full-length proteins, to designer cell culture systems that present multiple biophysical and biochemical cues in tandem, it is discussed how the integration of combinatorics with high content imaging and analysis is essential to extracting biologically meaningful information from large scale cellular screens to inform the design of next generation biomaterials.
Collapse
Affiliation(s)
- Douglas Zhang
- Department of Materials Science and Engineering; University of Illinois at Urbana-Champaign; Urbana Illinois 61801
| | - Junmin Lee
- Department of Materials Science and Engineering; University of Illinois at Urbana-Champaign; Urbana Illinois 61801
| | - Kristopher A. Kilian
- Department of Materials Science and Engineering; University of Illinois at Urbana-Champaign; Urbana Illinois 61801
- Department of Bioengineering; University of Illinois at Urbana-Champaign; Urbana Illinois 61801
| |
Collapse
|
74
|
Tsuji K, Suleiman H, Miner JH, Daley JM, Capen DE, Păunescu TG, Lu HAJ. Ultrastructural Characterization of the Glomerulopathy in Alport Mice by Helium Ion Scanning Microscopy (HIM). Sci Rep 2017; 7:11696. [PMID: 28916834 PMCID: PMC5601433 DOI: 10.1038/s41598-017-12064-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 09/01/2017] [Indexed: 01/19/2023] Open
Abstract
The glomerulus exercises its filtration barrier function by establishing a complex filtration apparatus consisting of podocyte foot processes, glomerular basement membrane and endothelial cells. Disruption of any component of the glomerular filtration barrier leads to glomerular dysfunction, frequently manifested as proteinuria. Ultrastructural studies of the glomerulus by transmission electron microscopy (TEM) and conventional scanning electron microscopy (SEM) have been routinely used to identify and classify various glomerular diseases. Here we report the application of newly developed helium ion scanning microscopy (HIM) to examine the glomerulopathy in a Col4a3 mutant/Alport syndrome mouse model. Our study revealed unprecedented details of glomerular abnormalities in Col4a3 mutants including distorted podocyte cell bodies and disorganized primary processes. Strikingly, we observed abundant filamentous microprojections arising from podocyte cell bodies and processes, and presence of unique bridging processes that connect the primary processes and foot processes in Alport mice. Furthermore, we detected an altered glomerular endothelium with disrupted sub-endothelial integrity. More importantly, we were able to clearly visualize the complex, three-dimensional podocyte and endothelial interface by HIM. Our study demonstrates that HIM provides nanometer resolution to uncover and rediscover critical ultrastructural characteristics of the glomerulopathy in Col4a3 mutant mice.
Collapse
Affiliation(s)
- Kenji Tsuji
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Hani Suleiman
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.,Division of Nephrology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jeffrey H Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, MO, USA
| | - James M Daley
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Diane E Capen
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Teodor G Păunescu
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Hua A Jenny Lu
- Center for Systems Biology, Program in Membrane Biology and Division of Nephrology, Department of Medicine, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
75
|
Siegerist F, Ribback S, Dombrowski F, Amann K, Zimmermann U, Endlich K, Endlich N. Structured illumination microscopy and automatized image processing as a rapid diagnostic tool for podocyte effacement. Sci Rep 2017; 7:11473. [PMID: 28904359 PMCID: PMC5597580 DOI: 10.1038/s41598-017-11553-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 08/22/2017] [Indexed: 01/19/2023] Open
Abstract
The morphology of podocyte foot processes is obligatory for renal function. Here we describe a method for the superresolution-visualization of podocyte foot processes using structured illumination microscopy of the slit diaphragm, which before has only been achieved by electron microscopy. As a proof of principle, we measured a mean foot process width of 0.249 ± 0.068 µm in healthy kidneys and a significant higher mean foot process width of 0.675 ± 0.256 µm in minimal change disease patients indicating effacement of foot processes. We then hypothesized that the slit length per glomerular capillary surface area (slit diaphragm density) could be used as an equivalent for the diagnosis of effacement. Using custom-made software we measured a mean value of 3.10 ± 0.27 µm−1 in healthy subjects and 1.83 ± 0.49 µm−1 in the minimal change disease patients. As foot process width was highly correlated with slit diaphragm density (R2 = 0.91), we concluded that our approach is a valid method for the diagnosis of foot process effacement. In summary, we present a new technique to quantify podocyte damage, which combines superresolution microscopy with automatized image processing. Due to its diverse advantages, we propose this technique to be included into routine diagnostics of glomerular histopathology.
Collapse
Affiliation(s)
- Florian Siegerist
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Silvia Ribback
- Department of Pathology, University Medicine Greifswald, Greifswald, Germany
| | - Frank Dombrowski
- Department of Pathology, University Medicine Greifswald, Greifswald, Germany
| | - Kerstin Amann
- Department of Nephropathology, Institute of Pathology, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Uwe Zimmermann
- Department of Urology, University Medicine Greifswald, Greifswald, Germany
| | - Karlhans Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Nicole Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany.
| |
Collapse
|
76
|
Abstract
Podocytes exhibit a unique cytoskeletal architecture that is fundamentally linked to their function in maintaining the kidney filtration barrier. The cytoskeleton regulates podocyte shape, structure, stability, slit diaphragm insertion, adhesion, plasticity, and dynamic response to environmental stimuli. Genetic mutations demonstrate that even slight impairment of the podocyte cytoskeletal apparatus results in proteinuria and glomerular disease. Moreover, mechanisms underpinning all acquired glomerular pathologies converge on disruption of the cytoskeleton, suggesting that this subcellular structure could be targeted for therapeutic purposes. This review summarizes our current understanding of the function of the cytoskeleton in podocytes and the associated implications for pathophysiology.
Collapse
Affiliation(s)
- Christoph Schell
- Institute of Surgical Pathology and.,Department of Medicine IV, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Germany
| | - Tobias B Huber
- Department of Medicine IV, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; .,III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and.,BIOSS Centre for Biological Signalling Studies and Center for Biological Systems Analysis (ZBSA), Albert-Ludwigs-University, Freiburg, Germany
| |
Collapse
|
77
|
Suleiman HY, Roth R, Jain S, Heuser JE, Shaw AS, Miner JH. Injury-induced actin cytoskeleton reorganization in podocytes revealed by super-resolution microscopy. JCI Insight 2017; 2:94137. [PMID: 28814668 DOI: 10.1172/jci.insight.94137] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/07/2017] [Indexed: 02/06/2023] Open
Abstract
The architectural integrity of tissues requires complex interactions, both between cells and between cells and the extracellular matrix. Fundamental to cell and tissue homeostasis are the specific mechanical forces conveyed by the actomyosin cytoskeleton. Here we used super-resolution imaging methods to visualize the actin cytoskeleton in the kidney glomerulus, an organized collection of capillaries that filters the blood to make the primary urine. Our analysis of both mouse and human glomeruli reveals a network of myosin IIA-containing contractile actin cables within podocyte cell bodies and major processes at the outer aspects of the glomerular tuft. These likely exert force on an underlying network of myosin IIA-negative, noncontractile actin fibers present within podocyte foot processes that function to both anchor the cells to the glomerular basement membrane and stabilize the slit diaphragm against the pressure of fluid flow. After injuries that disrupt the kidney filtration barrier and cause foot process effacement, the podocyte's contractile actomyosin network relocates to the basolateral surface of the cell, manifesting as sarcomere-like structures juxtaposed to the basement membrane. Our findings suggest a new model of the podocyte actin cytoskeleton in health and disease and suggest the existence of novel mechanisms that regulate podocyte architecture.
Collapse
Affiliation(s)
- Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robyn Roth
- Washington University Center for Cellular Imaging, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Sanjay Jain
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - John E Heuser
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto, Japan
| | | | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| |
Collapse
|
78
|
Transcriptomic Analysis of Ribosome-Bound mRNA in Cortical Neurites In Vivo. J Neurosci 2017; 37:8688-8705. [PMID: 28821669 DOI: 10.1523/jneurosci.3044-16.2017] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 06/29/2017] [Accepted: 07/21/2017] [Indexed: 01/19/2023] Open
Abstract
Localized translation in neurites helps regulate synaptic strength and development. Dysregulation of local translation is associated with many neurological disorders. However, due to technical limitations, study of this phenomenon has largely been limited to brain regions with laminar organization of dendrites such as the hippocampus or cerebellum. It has not been examined in the cortex, a region of importance for most neurological disorders, where dendrites of each neuronal population are densely intermingled with cell bodies of others. Therefore, we have developed a novel method, SynapTRAP, which combines synaptoneurosomal fractionation with translating ribosome affinity purification to identify ribosome-bound mRNA in processes of genetically defined cell types. We demonstrate SynapTRAP's efficacy and report local translation in the cortex of mice, where we identify a subset of mRNAs that are translated in dendrites by neuronal ribosomes. These mRNAs have disproportionately longer lengths, enrichment for FMRP binding and G-quartets, and their genes are under greater evolutionary constraint in humans. In addition, we show that alternative splicing likely regulates this phenomenon. Overall, SynapTRAP allows for rapid isolation of cell-type-specific localized translation and is applicable to classes of previously inaccessible neuronal and non-neuronal cells in vivoSIGNIFICANCE STATEMENT Instructions for making proteins are found in the genome, housed within the nucleus of each cell. These are then copied as RNA and exported to manufacture new proteins. However, in the brain, memory is thought to be encoded by strengthening individual connections (synapses) between neurons far from the nucleus. Thus, to efficiently make new proteins specifically where they are needed, neurons can transport RNAs to sites near synapses to locally produce proteins. Importantly, several mutations that cause autism disrupt this process. It has been assumed this process occurs in all brain regions, but has never been measured in the cortex. We applied a newly developed method measure to study, for the first time, local translation in cortical neurons.
Collapse
|
79
|
Köhler S, Wojcik M, Xu K, Dernburg AF. Superresolution microscopy reveals the three-dimensional organization of meiotic chromosome axes in intact Caenorhabditis elegans tissue. Proc Natl Acad Sci U S A 2017; 114:E4734-E4743. [PMID: 28559338 PMCID: PMC5474826 DOI: 10.1073/pnas.1702312114] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
When cells enter meiosis, their chromosomes reorganize as linear arrays of chromatin loops anchored to a central axis. Meiotic chromosome axes form a platform for the assembly of the synaptonemal complex (SC) and play central roles in other meiotic processes, including homologous pairing, recombination, and chromosome segregation. However, little is known about the 3D organization of components within the axes, which include cohesin complexes and additional meiosis-specific proteins. Here, we investigate the molecular organization of meiotic chromosome axes in Caenorhabditis elegans through STORM (stochastic optical reconstruction microscopy) and PALM (photo-activated localization microscopy) superresolution imaging of intact germ-line tissue. By tagging one axis protein (HIM-3) with a photoconvertible fluorescent protein, we established a spatial reference for other components, which were localized using antibodies against epitope tags inserted by CRISPR/Cas9 genome editing. Using 3D averaging, we determined the position of all known components within synapsed chromosome axes to high spatial precision in three dimensions. We find that meiosis-specific HORMA domain proteins span a gap between cohesin complexes and the central region of the SC, consistent with their essential roles in SC assembly. Our data further suggest that the two different meiotic cohesin complexes are distinctly arranged within the axes: Although cohesin complexes containing the kleisin REC-8 protrude above and below the plane defined by the SC, complexes containing COH-3 or -4 kleisins form a central core, which may physically separate sister chromatids. This organization may help to explain the role of the chromosome axes in promoting interhomolog repair of meiotic double-strand breaks by inhibiting intersister repair.
Collapse
Affiliation(s)
- Simone Köhler
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3220
- Howard Hughes Medical Institute, Chevy Chase, MD 20815
| | - Michal Wojcik
- Department of Chemistry, University of California, Berkeley, CA 94720-3220
- California Institute for Quantitative Biosciences, Berkeley, CA 94720
| | - Ke Xu
- Department of Chemistry, University of California, Berkeley, CA 94720-3220;
- California Institute for Quantitative Biosciences, Berkeley, CA 94720
- Division of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Abby F Dernburg
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3220;
- Howard Hughes Medical Institute, Chevy Chase, MD 20815
- California Institute for Quantitative Biosciences, Berkeley, CA 94720
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| |
Collapse
|
80
|
The FERM protein EPB41L5 regulates actomyosin contractility and focal adhesion formation to maintain the kidney filtration barrier. Proc Natl Acad Sci U S A 2017; 114:E4621-E4630. [PMID: 28536193 DOI: 10.1073/pnas.1617004114] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Podocytes form the outer part of the glomerular filter, where they have to withstand enormous transcapillary filtration forces driving glomerular filtration. Detachment of podocytes from the glomerular basement membrane precedes most glomerular diseases. However, little is known about the regulation of podocyte adhesion in vivo. Thus, we systematically screened for podocyte-specific focal adhesome (FA) components, using genetic reporter models in combination with iTRAQ-based mass spectrometry. This approach led to the identification of FERM domain protein EPB41L5 as a highly enriched podocyte-specific FA component in vivo. Genetic deletion of Epb41l5 resulted in severe proteinuria, detachment of podocytes, and development of focal segmental glomerulosclerosis. Remarkably, by binding and recruiting the RhoGEF ARGHEF18 to the leading edge, EPB41L5 directly controls actomyosin contractility and subsequent maturation of focal adhesions, cell spreading, and migration. Furthermore, EPB41L5 controls matrix-dependent outside-in signaling by regulating the focal adhesome composition. Thus, by linking extracellular matrix sensing and signaling, focal adhesion maturation, and actomyosin activation EPB41L5 ensures the mechanical stability required for podocytes at the kidney filtration barrier. Finally, a diminution of EPB41L5-dependent signaling programs appears to be a common theme of podocyte disease, and therefore offers unexpected interventional therapeutic strategies to prevent podocyte loss and kidney disease progression.
Collapse
|
81
|
Diverse protocols for correlative super-resolution fluorescence imaging and electron microscopy of chemically fixed samples. Nat Protoc 2017; 12:916-946. [PMID: 28384138 DOI: 10.1038/nprot.2017.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Our groups have recently developed related approaches for sample preparation for super-resolution imaging within endogenous cellular environments using correlative light and electron microscopy (CLEM). Four distinct techniques for preparing and acquiring super-resolution CLEM data sets for aldehyde-fixed specimens are provided, including Tokuyasu cryosectioning, whole-cell mount, cell unroofing and platinum replication, and resin embedding and sectioning. The choice of the best protocol for a given application depends on a number of criteria that are discussed in detail. Tokuyasu cryosectioning is relatively rapid but is limited to small, delicate specimens. Whole-cell mount has the simplest sample preparation but is restricted to surface structures. Cell unroofing and platinum replication creates high-contrast, 3D images of the cytoplasmic surface of the plasma membrane but is more challenging than whole-cell mount. Resin embedding permits serial sectioning of large samples but is limited to osmium-resistant probes, and is technically difficult. Expected results from these protocols include super-resolution localization (∼10-50 nm) of fluorescent targets within the context of electron microscopy ultrastructure, which can help address cell biological questions. These protocols can be completed in 2-7 d, are compatible with a number of super-resolution imaging protocols, and are broadly applicable across biology.
Collapse
|
82
|
Abstract
The last 5 years have witnessed tremendous advances in both light- and electron-microscopic techniques in the biomedical sciences. Application of these new cutting-edge methods to glomerular biology has advanced considerably and, in part, completed our endeavor to draw a detailed map of the glomerular tuft. The scope of this review is to illustrate these new insights within both the morphometry of podocyte cells and the architecture of the glomerular filtration barrier and to assess whether these findings have indeed had an impact on our biological understanding of glomerular function.
Collapse
Affiliation(s)
- Florian Grahammer
- Department of Medicine IV, Medical Center and Faculty of Medicine, University of Freiburg, Breisacherstrasse 66, 79106, Freiburg, Germany. .,III. Medical Clinic, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
| |
Collapse
|
83
|
Kriz W, Löwen J, Federico G, van den Born J, Gröne E, Gröne HJ. Accumulation of worn-out GBM material substantially contributes to mesangial matrix expansion in diabetic nephropathy. Am J Physiol Renal Physiol 2017; 312:F1101-F1111. [PMID: 28228399 DOI: 10.1152/ajprenal.00020.2017] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/07/2017] [Accepted: 02/17/2017] [Indexed: 12/12/2022] Open
Abstract
Thickening of the glomerular basement membrane (GBM) and expansion of the mesangial matrix are hallmarks of diabetic nephropathy (DN), generally considered to emerge from different sites of overproduction: GBM components from podocytes and mesangial matrix from mesangial cells. Reevaluation of 918 biopsies with DN revealed strong evidence that these mechanisms are connected to each other, wherein excess GBM components fail to undergo degradation and are deposited in the mesangium. These data do not exclude that mesangial cells also synthesize components that contribute to the accumulation of matrix in the mesangium. Light, electron microscopic, immunofluorescence, and in situ hybridization studies clearly show that the thickening of the GBM is due not only to overproduction of components of the mature GBM (α3 and α5 chains of collagen IV and agrin) by podocytes but also to resumed increased synthesis of the α1 chain of collagen IV and of perlecan by endothelial cells usually seen during embryonic development. We hypothesize that these abnormal production mechanisms are caused by different processes: overproduction of mature GBM-components by the diabetic milieu and regression of endothelial cells to an embryonic production mode by decreased availability of mediators from podocytes.
Collapse
Affiliation(s)
- Wilhelm Kriz
- Department of Neuroanatomy, Medical Faculty Mannheim, University Heidelberg, Germany;
| | - Jana Löwen
- Department of Neuroanatomy, Medical Faculty Mannheim, University Heidelberg, Germany.,Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany; and
| | - Giuseppina Federico
- Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany; and
| | - Jacob van den Born
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Elisabeth Gröne
- Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany; and
| | - Hermann Josef Gröne
- Department of Cellular and Molecular Pathology, German Cancer Research Center, Heidelberg, Germany; and
| |
Collapse
|
84
|
Omachi K, Miyakita R, Fukuda R, Kai Y, Suico MA, Yokota T, Kamura M, Shuto T, Kai H. Long-term treatment with EGFR inhibitor erlotinib attenuates renal inflammatory cytokines but not nephropathy in Alport syndrome mouse model. Clin Exp Nephrol 2017; 21:952-960. [DOI: 10.1007/s10157-017-1386-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 01/19/2017] [Indexed: 10/20/2022]
|
85
|
Müller A, Neukam M, Ivanova A, Sönmez A, Münster C, Kretschmar S, Kalaidzidis Y, Kurth T, Verbavatz JM, Solimena M. A Global Approach for Quantitative Super Resolution and Electron Microscopy on Cryo and Epoxy Sections Using Self-labeling Protein Tags. Sci Rep 2017; 7:23. [PMID: 28154417 PMCID: PMC5428382 DOI: 10.1038/s41598-017-00033-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 12/20/2016] [Indexed: 01/19/2023] Open
Abstract
Correlative light and electron microscopy (CLEM) is a powerful approach to investigate the molecular ultrastructure of labeled cell compartments. However, quantitative CLEM studies are rare, mainly due to small sample sizes and the sensitivity of fluorescent proteins to strong fixatives and contrasting reagents for EM. Here, we show that fusion of a self-labeling protein to insulin allows for the quantification of age-distinct insulin granule pools in pancreatic beta cells by a combination of super resolution and transmission electron microscopy on Tokuyasu cryosections. In contrast to fluorescent proteins like GFP organic dyes covalently bound to self-labeling proteins retain their fluorescence also in epoxy resin following high pressure freezing and freeze substitution, or remarkably even after strong chemical fixation. This enables for the assessment of age-defined granule morphology and degradation. Finally, we demonstrate that this CLEM protocol is highly versatile, being suitable for single and dual fluorescent labeling and detection of different proteins with optimal ultrastructure preservation and contrast.
Collapse
Affiliation(s)
- Andreas Müller
- Molecular Diabetology, University Hospital and Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany.,Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at the University Hospital Carl Gustav Carus and Faculty of Medicine of the TU Dresden, Dresden, Germany
| | - Martin Neukam
- Molecular Diabetology, University Hospital and Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany.,Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at the University Hospital Carl Gustav Carus and Faculty of Medicine of the TU Dresden, Dresden, Germany
| | - Anna Ivanova
- Molecular Diabetology, University Hospital and Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany.,Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at the University Hospital Carl Gustav Carus and Faculty of Medicine of the TU Dresden, Dresden, Germany
| | - Anke Sönmez
- Molecular Diabetology, University Hospital and Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany.,Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at the University Hospital Carl Gustav Carus and Faculty of Medicine of the TU Dresden, Dresden, Germany
| | - Carla Münster
- Molecular Diabetology, University Hospital and Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany.,Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at the University Hospital Carl Gustav Carus and Faculty of Medicine of the TU Dresden, Dresden, Germany
| | - Susanne Kretschmar
- Center for Regenerative Therapies Dresden (CRTD), TU Dresden, Dresden, Germany.,Biotechnology Center of the TU Dresden (BIOTEC), Dresden, Germany
| | - Yannis Kalaidzidis
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany.,Faculty of Bioengineering and Bioinformatics, Moscow State University, Moscow, Russia
| | - Thomas Kurth
- Center for Regenerative Therapies Dresden (CRTD), TU Dresden, Dresden, Germany.,Biotechnology Center of the TU Dresden (BIOTEC), Dresden, Germany
| | - Jean-Marc Verbavatz
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany.,Institut Jacques Monod, Université Paris Diderot, Paris, France
| | - Michele Solimena
- Molecular Diabetology, University Hospital and Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden, Germany. .,Paul Langerhans Institute Dresden (PLID) of the Helmholtz Center Munich at the University Hospital Carl Gustav Carus and Faculty of Medicine of the TU Dresden, Dresden, Germany. .,Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany.
| |
Collapse
|
86
|
Abstract
In this commentary, I review recent advances in Alport syndrome genetics, diagnostics, and therapeutics. I also offer some opinions regarding strategies to optimize the early identification of affected individuals to promote early therapeutic intervention.
Collapse
Affiliation(s)
- Clifford Kashtan
- Department of Pediatrics, Division of Pediatric Nephrology, University of Minnesota Medical School, Minneapolis, MN, USA
| |
Collapse
|
87
|
Hauser M, Wojcik M, Kim D, Mahmoudi M, Li W, Xu K. Correlative Super-Resolution Microscopy: New Dimensions and New Opportunities. Chem Rev 2017; 117:7428-7456. [PMID: 28045508 DOI: 10.1021/acs.chemrev.6b00604] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Correlative microscopy, the integration of two or more microscopy techniques performed on the same sample, produces results that emphasize the strengths of each technique while offsetting their individual weaknesses. Light microscopy has historically been a central method in correlative microscopy due to its widespread availability, compatibility with hydrated and live biological samples, and excellent molecular specificity through fluorescence labeling. However, conventional light microscopy can only achieve a resolution of ∼300 nm, undercutting its advantages in correlations with higher-resolution methods. The rise of super-resolution microscopy (SRM) over the past decade has drastically improved the resolution of light microscopy to ∼10 nm, thus creating exciting new opportunities and challenges for correlative microscopy. Here we review how these challenges are addressed to effectively correlate SRM with other microscopy techniques, including light microscopy, electron microscopy, cryomicroscopy, atomic force microscopy, and various forms of spectroscopy. Though we emphasize biological studies, we also discuss the application of correlative SRM to materials characterization and single-molecule reactions. Finally, we point out current limitations and discuss possible future improvements and advances. We thus demonstrate how a correlative approach adds new dimensions of information and provides new opportunities in the fast-growing field of SRM.
Collapse
Affiliation(s)
- Meghan Hauser
- Department of Chemistry, University of California , Berkeley, California 94720, United States
| | - Michal Wojcik
- Department of Chemistry, University of California , Berkeley, California 94720, United States
| | - Doory Kim
- Department of Chemistry, University of California , Berkeley, California 94720, United States
| | - Morteza Mahmoudi
- Center for Nanomedicine and Department of Anesthesiology, Brigham and Women's Hospital, Harvard Medical School , Boston, Massachusetts 02115, United States
| | - Wan Li
- Department of Chemistry, University of California , Berkeley, California 94720, United States
| | - Ke Xu
- Department of Chemistry, University of California , Berkeley, California 94720, United States.,Division of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| |
Collapse
|
88
|
Johnson E, Kaufmann R. Preserving the photoswitching ability of standard fluorescent proteins for correlative in-resin super-resolution and electron microscopy. Methods Cell Biol 2017; 140:49-67. [DOI: 10.1016/bs.mcb.2017.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
89
|
Meehan DT, Delimont D, Dufek B, Zallocchi M, Phillips G, Gratton MA, Cosgrove D. Endothelin-1 mediated induction of extracellular matrix genes in strial marginal cells underlies strial pathology in Alport mice. Hear Res 2016; 341:100-108. [PMID: 27553900 PMCID: PMC5086449 DOI: 10.1016/j.heares.2016.08.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 07/21/2016] [Accepted: 08/15/2016] [Indexed: 12/20/2022]
Abstract
Alport syndrome, a type IV collagen disorder, manifests as glomerular disease associated with hearing loss with thickening of the glomerular and strial capillary basement membranes (SCBMs). We have identified a role for endothelin-1 (ET-1) activation of endothelin A receptors (ETARs) in glomerular pathogenesis. Here we explore whether ET-1 plays a role in strial pathology. Wild type (WT) and Alport mice were treated with the ETAR antagonist, sitaxentan. The stria vascularis was analyzed for SCBM thickness and for extracellular matrix (ECM) proteins. Additional WT and Alport mice were exposed to noise or hypoxia and the stria analyzed for hypoxia-related and ECM genes. A strial marginal cell line cultured under hypoxic conditions, or stimulated with ET-1 was analyzed for expression of hypoxia-related and ECM transcripts. Noise exposure resulted in significantly elevated ABR thresholds in Alport mice relative to wild type littermates. Alport stria showed elevated expression of collagen α1(IV), laminin α2, and laminin α5 proteins relative to WT. SCBM thickening and elevated ECM protein expression was ameliorated by ETAR blockade. Stria from normoxic Alport mice and hypoxic WT mice showed upregulation of hypoxia-related, ECM, and ET-1 transcripts. Both ET-1 stimulation and hypoxia up-regulated ECM transcripts in cultured marginal cells. We conclude that ET-1 mediated activation of ETARs on strial marginal cells results in elevated expression of ECM genes and thickening of the SCBMs in Alport mice. SCBM thickening results in hypoxic stress further elevating ECM and ET-1 gene expression, exacerbating strial pathology.
Collapse
Affiliation(s)
| | | | - Brianna Dufek
- Boys Town National Research Hospital, Omaha, NE, USA
| | | | | | | | - Dominic Cosgrove
- Boys Town National Research Hospital, Omaha, NE, USA; University of Nebraska Medical Center, Omaha, NE, USA.
| |
Collapse
|
90
|
Abstract
Treatment and management of kidney disease currently presents an enormous global burden, and the application of nanotechnology principles to renal disease therapy, although still at an early stage, has profound transformative potential. The increasing translation of nanomedicines to the clinic, alongside research efforts in tissue regeneration and organ-on-a-chip investigations, are likely to provide novel solutions to treat kidney diseases. Our understanding of renal anatomy and of how the biological and physico-chemical properties of nanomedicines (the combination of a nanocarrier and a drug) influence their interactions with renal tissues has improved dramatically. Tailoring of nanomedicines in terms of kidney retention and binding to key membranes and cell populations associated with renal diseases is now possible and greatly enhances their localization, tolerability, and efficacy. This Review outlines nanomedicine characteristics central to improved targeting of renal cells and highlights the prospects, challenges, and opportunities of nanotechnology-mediated therapies for renal diseases.
Collapse
|
91
|
Three-dimensional electron microscopy reveals the evolution of glomerular barrier injury. Sci Rep 2016; 6:35068. [PMID: 27725732 PMCID: PMC5057164 DOI: 10.1038/srep35068] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 09/20/2016] [Indexed: 12/26/2022] Open
Abstract
Glomeruli are highly sophisticated filters and glomerular disease is the leading cause of kidney failure. Morphological change in glomerular podocytes and the underlying basement membrane are frequently observed in disease, irrespective of the underlying molecular etiology. Standard electron microscopy techniques have enabled the identification and classification of glomerular diseases based on two-dimensional information, however complex three-dimensional ultrastructural relationships between cells and their extracellular matrix cannot be easily resolved with this approach. We employed serial block face-scanning electron microscopy to investigate Alport syndrome, the commonest monogenic glomerular disease, and compared findings to other genetic mouse models of glomerular disease (Myo1e−/−, Ptpro−/−). These analyses revealed the evolution of basement membrane and cellular defects through the progression of glomerular injury. Specifically we identified sub-podocyte expansions of the basement membrane with both cellular and matrix gene defects and found a corresponding reduction in podocyte foot process number. Furthermore, we discovered novel podocyte protrusions invading into the glomerular basement membrane in disease and these occurred frequently in expanded regions of basement membrane. These findings provide new insights into mechanisms of glomerular barrier dysfunction and suggest that common cell-matrix-adhesion pathways are involved in the progression of disease regardless of the primary insult.
Collapse
|
92
|
Zennaro C, Rastaldi MP, Bakeine GJ, Delfino R, Tonon F, Farra R, Grassi G, Artero M, Tormen M, Carraro M. A nanoporous surface is essential for glomerular podocyte differentiation in three-dimensional culture. Int J Nanomedicine 2016; 11:4957-4973. [PMID: 27757030 PMCID: PMC5053378 DOI: 10.2147/ijn.s110201] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although it is well recognized that cell–matrix interactions are based on both molecular and geometrical characteristics, the relationship between specific cell types and the three-dimensional morphology of the surface to which they are attached is poorly understood. This is particularly true for glomerular podocytes – the gatekeepers of glomerular filtration – which completely enwrap the glomerular basement membrane with their primary and secondary ramifications. Nanotechnologies produce biocompatible materials which offer the possibility to build substrates which differ only by topology in order to mimic the spatial organization of diverse basement membranes. With this in mind, we produced and utilized rough and porous surfaces obtained from silicon to analyze the behavior of two diverse ramified cells: glomerular podocytes and a neuronal cell line used as a control. Proper differentiation and development of ramifications of both cell types was largely influenced by topographical characteristics. Confirming previous data, the neuronal cell line acquired features of maturation on rough nanosurfaces. In contrast, podocytes developed and matured preferentially on nanoporous surfaces provided with grooves, as shown by the organization of the actin cytoskeleton stress fibers and the proper development of vinculin-positive focal adhesions. On the basis of these findings, we suggest that in vitro studies regarding podocyte attachment to the glomerular basement membrane should take into account the geometrical properties of the surface on which the tests are conducted because physiological cellular activity depends on the three-dimensional microenvironment.
Collapse
Affiliation(s)
- Cristina Zennaro
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste
| | | | - Gerald James Bakeine
- Department of Radiology, San Martino University Hospital, University of Genoa, Genoa
| | - Riccarda Delfino
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste
| | - Federica Tonon
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste
| | - Rossella Farra
- Department of Engineering and Architecture, University of Trieste
| | - Gabriele Grassi
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste; Department of Life Sciences, Cattinara University Hospital, University of Trieste
| | - Mary Artero
- Azienda Sanitaria Universitaria Integrata di Trieste, Trieste
| | | | - Michele Carraro
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste
| |
Collapse
|
93
|
Topographic contrast of ultrathin cryo-sections for correlative super-resolution light and electron microscopy. Sci Rep 2016; 6:34062. [PMID: 27666401 PMCID: PMC5036093 DOI: 10.1038/srep34062] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 09/07/2016] [Indexed: 01/19/2023] Open
Abstract
Fluorescence microscopy reveals molecular expression at nanometer resolution but lacks ultrastructural context information. This deficit often hinders a clear interpretation of results. Electron microscopy provides this contextual subcellular detail, but protein identification can often be problematic. Correlative light and electron microscopy produces complimentary information that expands our knowledge of protein expression in cells and tissue. Inherent methodological difficulties are however encountered when combining these two very different microscopy technologies. We present a quick, simple and reproducible method for protein localization by conventional and super-resolution light microscopy combined with platinum shadowing and scanning electron microscopy to obtain topographic contrast from the surface of ultrathin cryo-sections. We demonstrate protein distribution at nuclear pores and at mitochondrial and plasma membranes in the extended topographical landscape of tissue.
Collapse
|
94
|
Borza DB. Glomerular basement membrane heparan sulfate in health and disease: A regulator of local complement activation. Matrix Biol 2016; 57-58:299-310. [PMID: 27609404 DOI: 10.1016/j.matbio.2016.09.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 08/30/2016] [Accepted: 09/01/2016] [Indexed: 12/26/2022]
Abstract
The glomerular basement membrane (GBM) is an essential component of the glomerular filtration barrier. Heparan sulfate proteoglycans such as agrin are major components of the GBM, along with α345(IV) collagen, laminin-521 and nidogen. A loss of GBM heparan sulfate chains is associated with proteinuria in several glomerular diseases and may contribute to the underlying pathology. As the major determinants of the anionic charge of the GBM, heparan sulfate chains have been thought to impart charge selectivity to the glomerular filtration, a view challenged by the negligible albuminuria in mice that lack heparan sulfate in the GBM. Recent studies provide increasing evidence that heparan sulfate chains modulate local complement activation by recruiting complement regulatory protein factor H, the major inhibitor of the alternative pathway in plasma. Factor H selectively inactivates C3b bound to surfaces bearing host-specific polyanions such as heparan sulfate, thus limiting complement activation on self surfaces such as the GBM, which are not protected by cell-bound complement regulators. We discuss mechanisms whereby the acquired loss of GBM heparan sulfate can impair the local regulation of the alternative pathway, exacerbating complement activation and glomerular injury in immune-mediated kidney diseases such as membranous nephropathy and lupus nephritis.
Collapse
Affiliation(s)
- Dorin-Bogdan Borza
- Department of Microbiology and Immunology, Meharry Medical College, 1005 Dr. D. B. Todd, Jr., Blvd., Nashville, TN 37208, USA.
| |
Collapse
|
95
|
Marshall CB. Rethinking glomerular basement membrane thickening in diabetic nephropathy: adaptive or pathogenic? Am J Physiol Renal Physiol 2016; 311:F831-F843. [PMID: 27582102 DOI: 10.1152/ajprenal.00313.2016] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 08/21/2016] [Indexed: 12/12/2022] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of chronic kidney disease in the United States and is a major cause of cardiovascular disease and death. DN develops insidiously over a span of years before clinical manifestations, including microalbuminuria and declining glomerular filtration rate (GFR), are evident. During the clinically silent period, structural lesions develop, including glomerular basement membrane (GBM) thickening, mesangial expansion, and glomerulosclerosis. Once microalbuminuria is clinically apparent, structural lesions are often considerably advanced, and GFR decline may then proceed rapidly toward end-stage kidney disease. Given the current lack of sensitive biomarkers for detecting early DN, a shift in focus toward examining the cellular and molecular basis for the earliest structural change in DN, i.e., GBM thickening, may be warranted. Observed within one to two years following the onset of diabetes, GBM thickening precedes clinically evident albuminuria. In the mature glomerulus, the podocyte is likely key in modifying the GBM, synthesizing and assembling matrix components, both in physiological and pathological states. Podocytes also secrete matrix metalloproteinases, crucial mediators in extracellular matrix turnover. Studies have shown that the critical podocyte-GBM interface is disrupted in the diabetic milieu. Just as healthy podocytes are essential for maintaining the normal GBM structure and function, injured podocytes likely have a fundamental role in upsetting the balance between the GBM's synthetic and degradative pathways. This article will explore the biological significance of GBM thickening in DN by reviewing what is known about the GBM's formation, its maintenance during health, and its disruption in DN.
Collapse
Affiliation(s)
- Caroline B Marshall
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and Department of Veterans Affairs Medical Center, Birmingham, Alabama
| |
Collapse
|
96
|
Abstract
Alport syndrome is the result of mutations in any of three type IV collagen genes, COL4A3, COL4A4, or COL4A5. Because the three collagen chains form heterotrimers, there is an absence of all three proteins in the basement membranes where they are expressed. In the glomerulus, the mature glomerular basement membrane type IV collagen network, normally comprised of two separate networks, α3(IV)/α4(IV)/α5(IV) and α1(IV)/α2(IV), is comprised entirely of collagen α1(IV)/α2. This review addresses the current state of our knowledge regarding the consequence of this change in basement membrane composition, including both the direct, via collagen receptor binding, and indirect, regarding influences on glomerular biomechanics. The state of our current understanding regarding mechanisms of glomerular disease initiation and progression will be examined, as will the current state of the art regarding emergent therapeutic approaches to slow or arrest glomerular disease in Alport patients.
Collapse
|
97
|
Cosgrove D, Liu S. Collagen IV diseases: A focus on the glomerular basement membrane in Alport syndrome. Matrix Biol 2016; 57-58:45-54. [PMID: 27576055 DOI: 10.1016/j.matbio.2016.08.005] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 08/05/2016] [Accepted: 08/17/2016] [Indexed: 12/21/2022]
Abstract
Alport syndrome is the result of mutations in any of three type IV collagen genes, COL4A3, COL4A4, or COL4A5. Because the three collagen chains form heterotrimers, there is an absence of all three proteins in the basement membranes where they are expressed. In the glomerulus, the mature glomerular basement membrane type IV collagen network, normally comprised of two separate networks, α3(IV)/α4(IV)/α5(IV) and α1(IV)/α2(IV), is comprised entirely of collagen α1(IV)/α2. This review addresses the current state of our knowledge regarding the consequence of this change in basement membrane composition, including both the direct, via collagen receptor binding, and indirect, regarding influences on glomerular biomechanics. The state of our current understanding regarding mechanisms of glomerular disease initiation and progression will be examined, as will the current state of the art regarding emergent therapeutic approaches to slow or arrest glomerular disease in Alport patients.
Collapse
|
98
|
Li P, Miao Y, Dani A, Vig M. α-SNAP regulates dynamic, on-site assembly and calcium selectivity of Orai1 channels. Mol Biol Cell 2016; 27:2542-53. [PMID: 27335124 PMCID: PMC4985256 DOI: 10.1091/mbc.e16-03-0163] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 06/17/2016] [Indexed: 01/01/2023] Open
Abstract
Ion channel subunits typically assemble in the endoplasmic reticulum. α-SNAP orchestrates a unique assembly and calcium selectivity of Orai1 subunits into functional multimers. Dynamic assembly of Orai1 and its dependence on α-SNAP could enable localization of calcium signals and regulation of rate and amount of calcium influx. Orai1 forms a highly calcium-selective pore of the calcium release activated channel, and α-SNAP is necessary for its function. Here we show that α-SNAP regulates on-site assembly of Orai1 dimers into calcium-selective multimers. We find that Orai1 is a dimer in resting primary mouse embryonic fibroblasts but displays variable stoichiometry in the plasma membrane of store-depleted cells. Remarkably, α-SNAP depletion induces formation of higher-order Orai1 oligomers, which permeate significant levels of sodium via Orai1 channels. Sodium permeation in α-SNAP–deficient cells cannot be corrected by tethering multiple Stim1 domains to Orai1 C-terminal tail, demonstrating that α-SNAP regulates functional assembly and calcium selectivity of Orai1 multimers independently of Stim1 levels. Fluorescence nanoscopy reveals sustained coassociation of α-SNAP with Stim1 and Orai1, and α-SNAP–depleted cells show faster and less constrained mobility of Orai1 within ER-PM junctions, suggesting Orai1 and Stim1 coentrapment without stable contacts. Furthermore, α-SNAP depletion significantly reduces fluorescence resonance energy transfer between Stim1 and Orai1 N-terminus but not C-terminus. Taken together, these data reveal a unique role of α-SNAP in the on-site functional assembly of Orai1 subunits and suggest that this process may, in part, involve enabling crucial low-affinity interactions between Orai1 N-terminus and Stim1.
Collapse
Affiliation(s)
- Peiyao Li
- Department of Pathology and Immunology, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110
| | - Yong Miao
- Department of Pathology and Immunology, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110
| | - Adish Dani
- Department of Pathology and Immunology, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110 Hope Center for Neurological Disorders, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110
| | - Monika Vig
- Department of Pathology and Immunology, School of Medicine, Washington University in St. Louis, St. Louis, MO 63110
| |
Collapse
|
99
|
Kim AH, Suleiman H, Shaw AS. New approaches in renal microscopy: volumetric imaging and superresolution microscopy. Curr Opin Nephrol Hypertens 2016; 25:159-67. [PMID: 27023834 PMCID: PMC4910820 DOI: 10.1097/mnh.0000000000000220] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
PURPOSE OF REVIEW Histologic and electron microscopic analysis of the kidney has provided tremendous insight into structures such as the glomerulus and nephron. Recent advances in imaging, such as deep volumetric approaches and superresolution microscopy, have the capacity to dramatically enhance our current understanding of the structure and function of the kidney. Volumetric imaging can generate images millimeters below the surface of the intact kidney. Superresolution microscopy breaks the diffraction barrier inherent in traditional light microscopy, enabling the visualization of fine structures. Here, we describe new approaches to deep volumetric and superresolution microscopy of the kidney. RECENT FINDINGS Rapid advances in lasers, microscopic objectives, and tissue preparation have transformed our ability to deep volumetric image the kidney. Innovations in sample preparation have allowed for superresolution imaging with electron microscopy correlation, providing unprecedented insight into the structures within the glomerulus. SUMMARY Technological advances in imaging have revolutionized our capacity to image both large volumes of tissue and the finest structural details of a cell. These new advances have the potential to provide additional profound observations into the normal and pathologic functions of the kidney.
Collapse
Affiliation(s)
- Alfred H.J. Kim
- Division of Rheumatology, Dept. of Internal Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Hani Suleiman
- Division of Immunobiology, Dept. of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA
| | - Andrey S. Shaw
- Division of Immunobiology, Dept. of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA
| |
Collapse
|
100
|
Endothelin A receptor activation on mesangial cells initiates Alport glomerular disease. Kidney Int 2016; 90:300-310. [PMID: 27165837 DOI: 10.1016/j.kint.2016.02.018] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 01/21/2016] [Accepted: 02/11/2016] [Indexed: 01/19/2023]
Abstract
Recent work demonstrates that Alport glomerular disease is mediated through a biomechanical strain-sensitive activation of mesangial actin dynamics. This occurs through a Rac1/CDC42 cross-talk mechanism that results in the invasion of the subcapillary spaces by mesangial filopodia. The filopodia deposit mesangial matrix proteins in the glomerular basement membrane, including laminin 211, which activates focal adhesion kinase in podocytes culminating in the up-regulation of proinflammatory cytokines and metalloproteinases. These events drive the progression of glomerulonephritis. Here we test whether endothelial cell-derived endothelin-1 is up-regulated in Alport glomeruli and further elevated by hypertension. Treatment of cultured mesangial cells with endothelin-1 activates the formation of drebrin-positive actin microspikes. These microspikes do not form when cells are treated with the endothelin A receptor antagonist sitaxentan or under conditions of small, interfering RNA knockdown of endothelin A receptor mRNA. Treatment of Alport mice with sitaxentan results in delayed onset of proteinuria, normalized glomerular basement membrane morphology, inhibition of mesangial filopodial invasion of the glomerular capillaries, normalization of glomerular expression of metalloproteinases and proinflammatory cytokines, increased life span, and prevention of glomerulosclerosis and interstitial fibrosis. Thus endothelin A receptor activation on mesangial cells is a key event in initiation of Alport glomerular disease in this model.
Collapse
|