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Egu DT, Schmitt T, Ernst N, Ludwig RJ, Fuchs M, Hiermaier M, Moztarzadeh S, Morỏn CS, Schmidt E, Beyersdorfer V, Spindler V, Steinert LS, Vielmuth F, Sigmund AM, Waschke J. EGFR Inhibition by Erlotinib Rescues Desmosome Ultrastructure and Keratin Anchorage and Protects Against Pemphigus Vulgaris IgG-Induced Acantholysis in Human Epidermis. J Invest Dermatol 2024:S0022-202X(24)00301-4. [PMID: 38642796 DOI: 10.1016/j.jid.2024.03.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 03/23/2024] [Accepted: 03/25/2024] [Indexed: 04/22/2024]
Abstract
Pemphigus is a severe blistering disease caused by autoantibodies primarily against the desmosomal cadherins desmoglein (DSG)1 and DSG3 which impair desmosome integrity. Especially for the acute phase, additional treatment options allowing to reduce corticosteroids would fulfill an unmet medical need. Here, we provide evidence that epidermal growth factor receptor (EGFR) inhibition by erlotinib ameliorates pemphigus vulgaris immunoglobulin G (PV-IgG) -induced acantholysis in intact human epidermis. PV-IgG caused phosphorylation of EGFR (Y845) and SRC in human epidermis. In line with that, a phosphotyrosine kinome analysis revealed a robust response associated with EGFR and SRC family kinase signaling in response to PV-IgG but not pemphigus foliaceus autoantibodies. Erlotinib inhibited PV-IgG-induced epidermal blistering and EGFR phosphorylation, loss of desmosomes as well as ultrastructural alterations of desmosome size, plaque symmetry, keratin filament insertion and restored the desmosome midline considered as hallmark of mature desmosomes. Erlotinib enhanced both single molecule DSG3 binding frequency and strength and delayed DSG3 fluorescence recovery supporting that EGFR inhibition increases DSG3 availability and cytoskeletal anchorage. Our data indicate that EGFR is a promising target for pemphigus therapy due to its link to several signaling pathways known to be involved in pemphigus pathogenesis.
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Affiliation(s)
- Desalegn Tadesse Egu
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Thomas Schmitt
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Nancy Ernst
- Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany; Department of Dermatology, University of Lübeck, Lübeck, Germany
| | - Ralf Joachim Ludwig
- Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany; Department of Dermatology, University of Lübeck, Lübeck, Germany
| | - Michael Fuchs
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Matthias Hiermaier
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Sina Moztarzadeh
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Carla Sebastià Morỏn
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany; Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain
| | - Enno Schmidt
- Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany; Department of Dermatology, University of Lübeck, Lübeck, Germany
| | - Vivien Beyersdorfer
- Department of Biomedicine, University of Basel, Basel, Switzerland, Institute of Anatomy and Experimental Morphology, University Medical Center Hamburg Eppendorf, Germany
| | - Volker Spindler
- Department of Biomedicine, University of Basel, Basel, Switzerland, Institute of Anatomy and Experimental Morphology, University Medical Center Hamburg Eppendorf, Germany
| | - Letyfee Sarah Steinert
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Franziska Vielmuth
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Anna Magdalena Sigmund
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany.
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2
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Pas HH, van der Molen M, van Nijen-Vos L, Nijenhuis M, Bremer J. The Autoimmune IgG Subclass Response Defines the IgG Deposition Pattern in Pemphigus Patient Skin. J Invest Dermatol 2024:S0022-202X(24)00028-9. [PMID: 38272208 DOI: 10.1016/j.jid.2023.12.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/21/2023] [Accepted: 12/21/2023] [Indexed: 01/27/2024]
Affiliation(s)
- Hendri H Pas
- Center of Expertise for Blistering Diseases, Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
| | - Marije van der Molen
- Center of Expertise for Blistering Diseases, Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Laura van Nijen-Vos
- Center of Expertise for Blistering Diseases, Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Miranda Nijenhuis
- Center of Expertise for Blistering Diseases, Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jeroen Bremer
- Center of Expertise for Blistering Diseases, Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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Aswath A, Alsahaf A, Giepmans BNG, Azzopardi G. Segmentation in large-scale cellular electron microscopy with deep learning: A literature survey. Med Image Anal 2023; 89:102920. [PMID: 37572414 DOI: 10.1016/j.media.2023.102920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 07/05/2023] [Accepted: 07/31/2023] [Indexed: 08/14/2023]
Abstract
Electron microscopy (EM) enables high-resolution imaging of tissues and cells based on 2D and 3D imaging techniques. Due to the laborious and time-consuming nature of manual segmentation of large-scale EM datasets, automated segmentation approaches are crucial. This review focuses on the progress of deep learning-based segmentation techniques in large-scale cellular EM throughout the last six years, during which significant progress has been made in both semantic and instance segmentation. A detailed account is given for the key datasets that contributed to the proliferation of deep learning in 2D and 3D EM segmentation. The review covers supervised, unsupervised, and self-supervised learning methods and examines how these algorithms were adapted to the task of segmenting cellular and sub-cellular structures in EM images. The special challenges posed by such images, like heterogeneity and spatial complexity, and the network architectures that overcame some of them are described. Moreover, an overview of the evaluation measures used to benchmark EM datasets in various segmentation tasks is provided. Finally, an outlook of current trends and future prospects of EM segmentation is given, especially with large-scale models and unlabeled images to learn generic features across EM datasets.
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Affiliation(s)
- Anusha Aswath
- Bernoulli Institute of Mathematics, Computer Science and Artificial Intelligence, University Groningen, Groningen, The Netherlands; Department of Biomedical Sciences of Cells and Systems, University Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | - Ahmad Alsahaf
- Department of Biomedical Sciences of Cells and Systems, University Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, University Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - George Azzopardi
- Bernoulli Institute of Mathematics, Computer Science and Artificial Intelligence, University Groningen, Groningen, The Netherlands
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4
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Gedon NKY, Bizikova P, Olivry T, Mendoza-Kuznetsova E, Oberkirchner U, Robertson JB, Linder KE. Histopathological characterisation of trunk-dominant canine pemphigus foliaceus, and comparison with classic facial and insecticide-triggered forms. Vet Dermatol 2023; 34:425-440. [PMID: 37316895 DOI: 10.1111/vde.13174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 03/14/2023] [Accepted: 03/24/2023] [Indexed: 06/16/2023]
Abstract
BACKGROUND While the clinical features were described recently, the histopathological characterisation of trunk-dominant canine pemphigus foliaceus (PF) is lacking, and whether it differs from classic facial or insecticide-triggered PF is unknown. HYPOTHESIS/OBJECTIVES This study describes the histopathological findings of trunk-dominant PF, and compares the results to classic facial and insecticide-triggered PF. ANIMALS Skin biopsies from 103 dogs with clinically characterised trunk-dominant (n = 33), classic facial (n = 26) and insecticide-triggered PF (n = 44) were included. MATERIALS AND METHODS Histological sections, randomised and blinded, were scored for over 50 morphological parameters of pustules, epidermis, dermis, adnexa and crusts. Intact pustule area and width were measured by digital microscopy. RESULTS In trunk-dominant PF, 77 intact pustules were predominantly subcorneal (0.0019-1.940 mm2 area, 0.0470-4.2532 mm wide), and contained from one to over 100 acantholytic keratinocytes. Pustules had boat acantholytic cells, corneocytes, perinuclear eosinophilic rings, neutrophil rosettes, acantholytic cell necrosis, rafts, cling-ons and/or eosinophils. Peripustular epidermal spongiosis, necrosis and lymphocyte exocytosis occurred, as did follicular pustules. Mixed dermal inflammation often contained eosinophils. Trunk-dominant PF did not differ from the other PF groups except for few parameters, such as having fewer rafts (p = 0.003). Additional autoimmune inflammatory patterns occurred in all PF groups. CONCLUSIONS AND CLINICAL RELEVANCE Trunk-dominant PF and other canine PF variants are histologically similar, which indicates shared pathomechanisms. The identification of common boat acantholytic cells and corneocyte separation has implications for the mechanisms of acantholysis. The diversity of histopathological and polyautoimmunity features support complicated immune mechanisms. Finally, results indicate that diagnostic biopsies cannot differentiate between these PF variants in dogs.
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Affiliation(s)
| | - Petra Bizikova
- College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Thierry Olivry
- College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | | | | | | | - Keith Emerson Linder
- College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
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Vielmuth F, Radeva MY, Yeruva S, Sigmund AM, Waschke J. cAMP: A master regulator of cadherin-mediated binding in endothelium, epithelium and myocardium. Acta Physiol (Oxf) 2023; 238:e14006. [PMID: 37243909 DOI: 10.1111/apha.14006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/05/2023] [Accepted: 05/22/2023] [Indexed: 05/29/2023]
Abstract
Regulation of cadherin-mediated cell adhesion is crucial not only for maintaining tissue integrity and barrier function in the endothelium and epithelium but also for electromechanical coupling within the myocardium. Therefore, loss of cadherin-mediated adhesion causes various disorders, including vascular inflammation and desmosome-related diseases such as the autoimmune blistering skin dermatosis pemphigus and arrhythmogenic cardiomyopathy. Mechanisms regulating cadherin-mediated binding contribute to the pathogenesis of diseases and may also be used as therapeutic targets. Over the last 30 years, cyclic adenosine 3',5'-monophosphate (cAMP) has emerged as one of the master regulators of cell adhesion in endothelium and, more recently, also in epithelial cells as well as in cardiomyocytes. A broad spectrum of experimental models from vascular physiology and cell biology applied by different generations of researchers provided evidence that not only cadherins of endothelial adherens junctions (AJ) but also desmosomal contacts in keratinocytes and the cardiomyocyte intercalated discs are central targets in this scenario. The molecular mechanisms involve protein kinase A- and exchange protein directly activated by cAMP-mediated regulation of Rho family GTPases and S665 phosphorylation of the AJ and desmosome adaptor protein plakoglobin. In line with this, phosphodiesterase 4 inhibitors such as apremilast have been proposed as a therapeutic strategy to stabilize cadherin-mediated adhesion in pemphigus and may also be effective to treat other disorders where cadherin-mediated binding is compromised.
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Affiliation(s)
- Franziska Vielmuth
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Mariya Y Radeva
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Sunil Yeruva
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Anna M Sigmund
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
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Cook I, Leyh TS. Sulfotransferase 2B1b, Sterol Sulfonation, and Disease. Pharmacol Rev 2023; 75:521-531. [PMID: 36549865 PMCID: PMC10158503 DOI: 10.1124/pharmrev.122.000679] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/18/2022] [Accepted: 12/07/2022] [Indexed: 12/24/2022] Open
Abstract
The primary function of human sulfotransferase 2B1b (SULT2B1b) is to sulfonate cholesterol and closely related sterols. SULT2B1b sterols perform a number of essential cellular functions. Many are signaling molecules whose activities are redefined by sulfonation-allosteric properties are switched "on" or "off," agonists are transformed into antagonists, and vice versa. Sterol sulfonation is tightly coupled to cholesterol homeostasis, and sulfonation imbalances are causally linked to cholesterol-related diseases including certain cancers, Alzheimer disease, and recessive X-linked ichthyosis-an orphan skin disease. Numerous studies link SULT2B1b activity to disease-relevant molecular processes. Here, these multifaceted processes are integrated into metabolic maps that highlight their interdependence and how their actions are regulated and coordinated by SULT2B1b oxysterol sulfonation. The maps help explain why SULT2B1b inhibition arrests the growth of certain cancers and make the novel prediction that SULT2B1b inhibition will suppress production of amyloid β (Aβ) plaques and tau fibrils while simultaneously stimulating Aβ plaque phagocytosis. SULT2B1b harbors a sterol-selective allosteric site whose structure is discussed as a template for creating inhibitors to regulate SULT2B1b and its associated biology. SIGNIFICANCE STATEMENT: Human sulfotransferase 2B1b (SULT2B1b) produces sterol-sulfate signaling molecules that maintain the homeostasis of otherwise pro-disease processes in cancer, Alzheimer disease, and X-linked ichthyosis-an orphan skin disease. The functions of sterol sulfates in each disease are considered and codified into metabolic maps that explain the interdependencies of the sterol-regulated networks and their coordinate regulation by SULT2B1b. The structure of the SULT2B1b sterol-sensing allosteric site is discussed as a means of controlling sterol sulfate biology.
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Affiliation(s)
- Ian Cook
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York
| | - Thomas S Leyh
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York
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Makuloluwa AK, Hamill KJ, Rauz S, Bosworth L, Haneef A, Romano V, Williams RL, Dartt DA, Kaye SB. The conjunctival extracellular matrix, related disorders and development of substrates for conjunctival restoration. Ocul Surf 2023; 28:322-335. [PMID: 34102309 DOI: 10.1016/j.jtos.2021.05.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 05/05/2021] [Accepted: 05/26/2021] [Indexed: 12/15/2022]
Abstract
The conjunctiva can be damaged by numerous diseases with scarring, loss of tissue and dysfunction. Depending on extent of damage, restoration of function may require a conjunctival graft. A wide variety of biological and synthetic substrates have been tested in the search for optimal conditions for ex vivo culture of conjunctival epithelial cells as a route toward tissue grafts. Each substrate has specific advantages but also disadvantages related to their unique physical and biological characteristics, and identification and development of an improved substrate remains a priority. To achieve the goal of mimicking and restoring a biological material, requires information from the material. Specifically, extracellular matrix (ECM) derived from conjunctival tissue. Knowledge of the composition and structure of native ECM and identifying contributions of individual components to its function would enable using or mimicking those components to develop improved biological substrates. ECM is comprised of two components: basement membrane secreted predominantly by epithelial cells containing laminins and type IV collagens, which directly support epithelial and goblet cell adhesion differentiation and growth and, interstitial matrix secreted by fibroblasts in lamina propria, which provides mechanical and structural support. This review presents current knowledge on anatomy, composition of conjunctival ECM and related conjunctival disorders. Requirements of potential substrates for conjunctival tissue engineering and transplantation are discussed. Biological and synthetic substrates and their components are described in an accompanying review.
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Affiliation(s)
- Aruni K Makuloluwa
- Department of Eye and Vision Science, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Kevin J Hamill
- Department of Eye and Vision Science, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Saaeha Rauz
- Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham and Birmingham and Midland Eye Centre, Dudley Road Birmingham, B18 7QU, UK
| | - Lucy Bosworth
- Department of Eye and Vision Science, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Atikah Haneef
- Department of Eye and Vision Science, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Vito Romano
- Department of Eye and Vision Science, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Rachel L Williams
- Department of Eye and Vision Science, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK
| | - Darlene A Dartt
- Schepens Eye Research Institute, Mass Eye and Ear Infirmary, Harvard Medical School, 20 Staniford St. Boston, MA, 02114, USA
| | - Stephen B Kaye
- Department of Eye and Vision Science, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool, L7 8TX, UK.
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Apremilast prevents blistering in human epidermis and stabilizes keratinocyte adhesion in pemphigus. Nat Commun 2023; 14:116. [PMID: 36624106 PMCID: PMC9829900 DOI: 10.1038/s41467-022-35741-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 12/21/2022] [Indexed: 01/10/2023] Open
Abstract
Pemphigus vulgaris is a life-threatening blistering skin disease caused by autoantibodies destabilizing desmosomal adhesion. Current therapies focus on suppression of autoantibody formation and thus treatments directly stabilizing keratinocyte adhesion would fulfill an unmet medical need. We here demonstrate that apremilast, a phosphodiesterase 4 inhibitor used in psoriasis, prevents skin blistering in pemphigus vulgaris. Apremilast abrogates pemphigus autoantibody-induced loss of keratinocyte cohesion in ex-vivo human epidermis, cultured keratinocytes in vitro and in vivo in mice. In parallel, apremilast inhibits keratin retraction as well as desmosome splitting, induces phosphorylation of plakoglobin at serine 665 and desmoplakin assembly into desmosomal plaques. We established a plakoglobin phospho-deficient mouse model that reveals fragile epidermis with altered organization of keratin filaments and desmosomal cadherins. In keratinocytes derived from these mice, intercellular adhesion is impaired and not rescued by apremilast. These data identify an unreported mechanism of desmosome regulation and propose that apremilast stabilizes keratinocyte adhesion and is protective in pemphigus.
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9
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Schmitt T, Hudemann C, Moztarzadeh S, Hertl M, Tikkanen R, Waschke J. Dsg3 epitope-specific signalling in pemphigus. Front Immunol 2023; 14:1163066. [PMID: 37143675 PMCID: PMC10151755 DOI: 10.3389/fimmu.2023.1163066] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 03/31/2023] [Indexed: 05/06/2023] Open
Abstract
Introduction Pemphigus is an autoantibody driven disease that impairs the barrier function of the skin and mucosa by disrupting desmosomes and thereby impeding cellular cohesion. It is known that the different clinical phenotypes of pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are dependent on the autoantibody profile and target antigens that, amongst others, are primarily desmoglein (Dsg)1 and/or Dsg3 for PV and Dsg1 for PF. However, it was reported that autoantibodiesagainst different epitopes of Dsg1 and Dsg3 can be pathogenic or not. The underlying mechanisms are very complex and involve both direct inhibition of Dsg interactions and downstream signalling. The aim of this study was to find out whether there is target-epitope-specific Dsg3 signalling by comparing the effects of the two pathogenic murine IgGs, 2G4 and AK23. Methods Dispase-based dissociation assay, Western Blot analysis, Stimulated emission depletion microscopy, Fura-based Ca2+ flux measurements, Rho/Rac G-Protein-linked immunosorbent assay, Enzyme-linked immunosorbent assay. Results The IgGs are directed against the EC5 and EC1 domain of Dsg3, respectively. The data show that 2G4 was less effective in causing loss of cell adhesion, compared to AK23. STED imaging revealed that both autoantibodies had similar effects on keratin retraction and reduction of desmosome number whereas only AK23 induced Dsg3 depletion. Moreover, both antibodies induced phosphorylation of p38MAPK and Akt whereas Src was phosphorylated upon treatment with AK23 only. Interestingly, Src and Akt activation were p38MAPK-dependent. All pathogenic effects were rescued by p38MAPK inhibition and AK23-mediated effects were also ameliorated by Src inhibition. Discussion The results give first insights into pemphigus autoantibody-induced Dsg3 epitope-specific signalling which is involved in pathogenic events such as Dsg3 depletion.
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Affiliation(s)
- Thomas Schmitt
- Instiute of Anatomy, Faculty of Medicine, Chair of Vegetative Anatomy, Ludwig-Maximilian -Universität (LMU) Munich, München, Germany
| | - Christoph Hudemann
- Department of Dermatology and Allergology, Philipps-University Marburg, Marburg, Germany
| | - Sina Moztarzadeh
- Instiute of Anatomy, Faculty of Medicine, Chair of Vegetative Anatomy, Ludwig-Maximilian -Universität (LMU) Munich, München, Germany
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps-University Marburg, Marburg, Germany
| | - Ritva Tikkanen
- Institute of Biochemistry, Medical Faculty, Justus-Liebig-University Giessen, Giessen, Germany
| | - Jens Waschke
- Instiute of Anatomy, Faculty of Medicine, Chair of Vegetative Anatomy, Ludwig-Maximilian -Universität (LMU) Munich, München, Germany
- *Correspondence: Jens Waschke,
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Hortsch M, Koney NKK, Oommen AM, Yohannan DG, Li Y, de Melo Leite ACR, Girão-Carmona VCC. Virtual Microscopy Goes Global: The Images Are Virtual and the Problems Are Real. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1421:79-124. [PMID: 37524985 DOI: 10.1007/978-3-031-30379-1_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
For the last two centuries, the scholarly education of histology and pathology has been based on technology, initially on the availability of low-cost, high-quality light microscopes, and more recently on the introduction of computers and e-learning approaches to biomedical education. Consequently, virtual microscopy (VM) is replacing glass slides and the traditional light microscope as the main instruments of instruction in histology and pathology laboratories. However, as with most educational changes, there are advantages and disadvantages associated with a new technology. The use of VM for the teaching of histology and pathology requires an extensive infrastructure and the availability of computing devices to all learners, both posing a considerable financial strain on schools and students. Furthermore, there may be valid reasons for practicing healthcare professionals to maintain competency in using light microscopes. In addition, some educators may be reluctant to embrace new technologies. These are some of the reasons why the introduction of VM as an integral part of histology and pathology instruction has been globally uneven. This paper compares the teaching of histology and pathology using traditional or VM in five different countries and their adjacent regions, representing developed, as well as developing areas of the globe. We identify general and local roadblocks to the introduction of this still-emerging didactic technology and outline solutions for overcoming these barriers.
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Affiliation(s)
- Michael Hortsch
- Departments of Cell and Developmental Biology and of Learning Health Sciences, University of Michigan, Ann Arbor, MI, USA.
| | - Nii Koney-Kwaku Koney
- Department of Anatomy, University of Ghana Medical School, University of Ghana, Korle Bu, Accra, Ghana
| | - Aswathy Maria Oommen
- Government Medical College Thiruvananthapuram, Thiruvananthapuram, Kerala, India
- Kerala University of Health Sciences, Thrissur, Kerala, India
| | - Doris George Yohannan
- Government Medical College Thiruvananthapuram, Thiruvananthapuram, Kerala, India
- Kerala University of Health Sciences, Thrissur, Kerala, India
| | - Yan Li
- Department of Anatomy, Histology and Embryology, Fudan University, Shanghai, China
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Radine UK, Bumiller-Bini Hoch V, Boldt ABW, Zillikens D, Ludwig RJ, Hammers CM, Klinger M, Hundt JE. Electron microscopy of desmosomal structures in the pemphigus human skin organ culture model. Front Med (Lausanne) 2022; 9:997387. [DOI: 10.3389/fmed.2022.997387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/18/2022] [Indexed: 11/15/2022] Open
Abstract
Pemphigus is a chronic autoimmune skin blistering disease, characterized by acantholysis and by the production of autoantibodies directed against the structural desmosomal proteins desmoglein 1 (DSG1) and/or DSG3. Model systems allow the identification and testing of new therapeutic targets. Here, we evaluated ultrastructural desmosomal morphology in the human skin organ culture (HSOC) model injected with either anti-desmoglein (DSG) 1/3 single-chain variable fragment (scFv, termed Px4-3), Staphylococcus aureus exfoliative toxin (ETA) as a reference and positive control, and normal human IgG as a negative control. Each experimental condition was evaluated in abdominal skin biopsies from five different donors. After 24 h of incubation, we processed the samples for histological and ultrastructural electron microscopy analyses. We found that Px4-3 or ETA induced a loss of desmosomes and increased interdesmosomal widening, similar to patient skin biopsies and other pemphigus models. Thus, we propose the HSOC pemphigus model as an attractive tool to unravel novel therapeutic targets.
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12
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Schmitt T, Pircher J, Steinert L, Meier K, Ghoreschi K, Vielmuth F, Kugelmann D, Waschke J. Dsg1 and Dsg3 Composition of Desmosomes Across Human Epidermis and Alterations in Pemphigus Vulgaris Patient Skin. Front Immunol 2022; 13:884241. [PMID: 35711465 PMCID: PMC9196036 DOI: 10.3389/fimmu.2022.884241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 04/12/2022] [Indexed: 11/13/2022] Open
Abstract
Desmosomes are important epidermal adhesion units and signalling hubs, which play an important role in pemphigus pathogenesis. Different expression patterns of the pemphigus autoantigens desmoglein (Dsg)1 and Dsg3 across different epidermal layers have been demonstrated. However, little is known about changes in desmosome composition in different epidermal layers or in patient skin. The aim of this study was thus to characterize desmosome composition in healthy and pemphigus skin using super-resolution microscopy. An increasing Dsg1/Dsg3 ratio from lower basal (BL) to uppermost granular layer (GL) was observed. Within BL desmosomes, Dsg1 and Dsg3 were more homogeneously distributed whereas superficial desmosomes mostly comprised one of the two molecules or domains containing either one but not both. Extradesmosomal, desmoplakin (Dp)-independent, co-localization of Dsg3 with plakoglobin (Pg) was found mostly in BL and extradesmosomal Dsg1 co-localization with Pg in all layers. In contrast, in the spinous layer (SL) most Dsg1 and Dsg3 staining was confined to desmosomes, as revealed by the co-localization with Dp. In pemphigus patient skin, Dsg1 and Dsg3 immunostaining was altered especially along blister edges. The number of desmosomes in patient skin was reduced significantly in basal and spinous layer keratinocytes with only few split desmosomes found. In addition, Dsg1-Pg co-localization at the apical BL and Dsg3-Pg co-localization in SL were significantly reduced in patients, suggesting that that extradesmosomal Dsg molecules were affected. These results support the hypothesis that pemphigus is a desmosome assembly disease and may help to explain histopathologic differences between pemphigus phenotypes.
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Affiliation(s)
- Thomas Schmitt
- Chair of Vegetative Anatomy, Instiute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-Universität München (LMU) Munich, München, Germany
| | - Julia Pircher
- Chair of Vegetative Anatomy, Instiute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-Universität München (LMU) Munich, München, Germany
| | - Letyfee Steinert
- Chair of Vegetative Anatomy, Instiute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-Universität München (LMU) Munich, München, Germany
| | - Katharina Meier
- Department of Dermatology, Venereology and Allergology, Charité-Universitätsmedizin Berli, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Kamran Ghoreschi
- Department of Dermatology, Venereology and Allergology, Charité-Universitätsmedizin Berli, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Franziska Vielmuth
- Chair of Vegetative Anatomy, Instiute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-Universität München (LMU) Munich, München, Germany
| | - Daniela Kugelmann
- Chair of Vegetative Anatomy, Instiute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-Universität München (LMU) Munich, München, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Instiute of Anatomy, Faculty of Medicine, Ludwig-Maximilian-Universität München (LMU) Munich, München, Germany
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Egu DT, Schmitt T, Waschke J. Mechanisms Causing Acantholysis in Pemphigus-Lessons from Human Skin. Front Immunol 2022; 13:884067. [PMID: 35720332 PMCID: PMC9205406 DOI: 10.3389/fimmu.2022.884067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 04/12/2022] [Indexed: 11/13/2022] Open
Abstract
Pemphigus vulgaris (PV) is an autoimmune bullous skin disease caused primarily by autoantibodies (PV-IgG) against the desmosomal adhesion proteins desmoglein (Dsg)1 and Dsg3. PV patient lesions are characterized by flaccid blisters and ultrastructurally by defined hallmarks including a reduction in desmosome number and size, formation of split desmosomes, as well as uncoupling of keratin filaments from desmosomes. The pathophysiology underlying the disease is known to involve several intracellular signaling pathways downstream of PV-IgG binding. Here, we summarize our studies in which we used transmission electron microscopy to characterize the roles of signaling pathways in the pathogenic effects of PV-IgG on desmosome ultrastructure in a human ex vivo skin model. Blister scores revealed inhibition of p38MAPK, ERK and PLC/Ca2+ to be protective in human epidermis. In contrast, inhibition of Src and PKC, which were shown to be protective in cell cultures and murine models, was not effective for human skin explants. The ultrastructural analysis revealed that for preventing skin blistering at least desmosome number (as modulated by ERK) or keratin filament insertion (as modulated by PLC/Ca2+) need to be ameliorated. Other pathways such as p38MAPK regulate desmosome number, size, and keratin insertion indicating that they control desmosome assembly and disassembly on different levels. Taken together, studies in human skin delineate target mechanisms for the treatment of pemphigus patients. In addition, ultrastructural analysis supports defining the specific role of a given signaling molecule in desmosome turnover at ultrastructural level.
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Bumiller-Bini Hoch V, Schneider L, Pumpe AE, Lüders E, Hundt JE, Boldt ABW. Marked to Die-Cell Death Mechanisms for Keratinocyte Acantholysis in Pemphigus Diseases. Life (Basel) 2022; 12:life12030329. [PMID: 35330080 PMCID: PMC8948972 DOI: 10.3390/life12030329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 11/17/2022] Open
Abstract
Pemphigus is a group of blistering autoimmune diseases causing painful skin lesions, characterized by acantholysis and by the production of autoantibodies against, mainly, adhesion proteins. We reviewed the literature for molecules and/ or features involved in the 12 cell death pathways described by Nomenclature Committee on Cell Death, taking place in pemphigus patients, cell lines, or human skin organ cultures treated with sera or IgG from pemphigus patients or in pemphigus mouse models, and found 61 studies mentioning 97 molecules involved in cell death pathways. Among the molecules, most investigated were pleiotropic molecules such as TNF and CASP3, followed by FASL and CASP8, and then by FAS, BAX, BCL2, and TP53, all involved in more than one pathway but interpreted to function only within apoptosis. Most of these previous investigations focused only on apoptosis, but four recent studies, using TUNEL assays and/or electron microscopy, disqualified this pathway as a previous event of acantholysis. For PV, apoptolysis was suggested as a cell death mechanism based on pathogenic autoantibodies diversity, mitochondrial dysfunction, and p38 MAPK signaling. To answer those many questions that remain on cell death and pemphigus, we propose well-controlled, statistically relevant investigations on pemphigus and cell death pathways besides apoptosis, to overcome the challenges of understanding the etiopathology of pemphigus diseases.
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Affiliation(s)
- Valéria Bumiller-Bini Hoch
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba 81531-980, Brazil; (V.B.-B.H.); (L.S.)
- Postgraduate Program in Genetics, Department of Genetics, Federal University of Paraná (UFPR), Curitiba 81531-980, Brazil
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany; (A.E.P.); (E.L.); (J.E.H.)
| | - Larissa Schneider
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba 81531-980, Brazil; (V.B.-B.H.); (L.S.)
| | - Anna Elisabeth Pumpe
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany; (A.E.P.); (E.L.); (J.E.H.)
| | - Emelie Lüders
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany; (A.E.P.); (E.L.); (J.E.H.)
| | - Jennifer Elisabeth Hundt
- Lübeck Institute of Experimental Dermatology, University of Lübeck, 23562 Lübeck, Germany; (A.E.P.); (E.L.); (J.E.H.)
| | - Angelica Beate Winter Boldt
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba 81531-980, Brazil; (V.B.-B.H.); (L.S.)
- Correspondence:
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Egu DT, Schmitt T, Sigmund AM, Waschke J. Electron microscopy reveals that phospholipase C and Ca2+ signaling regulate keratin filament uncoupling from desmosomes in Pemphigus. Ann Anat 2022; 241:151904. [DOI: 10.1016/j.aanat.2022.151904] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 12/27/2022]
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Schmitt T, Waschke J. Autoantibody-Specific Signalling in Pemphigus. Front Med (Lausanne) 2021; 8:701809. [PMID: 34434944 PMCID: PMC8381052 DOI: 10.3389/fmed.2021.701809] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/08/2021] [Indexed: 12/11/2022] Open
Abstract
Pemphigus is a severe autoimmune disease impairing barrier functions of epidermis and mucosa. Autoantibodies primarily target the desmosomal adhesion molecules desmoglein (Dsg) 1 and Dsg 3 and induce loss of desmosomal adhesion. Strikingly, autoantibody profiles in pemphigus correlate with clinical phenotypes. Mucosal-dominant pemphigus vulgaris (PV) is characterised by autoantibodies (PV-IgG) against Dsg3 whereas epidermal blistering in PV and pemphigus foliaceus (PF) is associated with autoantibodies against Dsg1. Therapy in pemphigus is evolving towards specific suppression of autoantibody formation and autoantibody depletion. Nevertheless, during the acute phase and relapses of the disease additional treatment options to stabilise desmosomes and thereby rescue keratinocyte adhesion would be beneficial. Therefore, the mechanisms by which autoantibodies interfere with adhesion of desmosomes need to be characterised in detail. Besides direct inhibition of Dsg adhesion, autoantibodies engage signalling pathways interfering with different steps of desmosome turn-over. With this respect, recent data indicate that autoantibodies induce separate signalling responses in keratinocytes via specific signalling complexes organised by Dsg1 and Dsg3 which transfer the signal of autoantibody binding into the cell. This hypothesis may also explain the different clinical pemphigus phenotypes.
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Affiliation(s)
- Thomas Schmitt
- Ludwig-Maximilian-Universität München, Anatomische Anstalt, Lehrstuhl Anatomie I - Vegetative Anatomie, Munich, Germany
| | - Jens Waschke
- Ludwig-Maximilian-Universität München, Anatomische Anstalt, Lehrstuhl Anatomie I - Vegetative Anatomie, Munich, Germany
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Zeng FAP, Murrell DF. State-of-the-art review of human autoimmune blistering diseases (AIBD). Vet Dermatol 2021; 32:524-e145. [PMID: 34351020 DOI: 10.1111/vde.13008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 11/28/2022]
Abstract
Autoimmune blistering diseases (AIBDs) are a heterogenous group of skin conditions, broadly classified into two categories depending on the location of blister formation: intraepidermal blistering in the pemphigus group and subepidermal blistering in the pemphigoid group. Although AIBDs occur in both humans and animals, the arsenal of data for human AIBDs far exceeds those of their animal counterpart. Therefore, the main purpose of this review is to highlight existing knowledge, and recent advances in the diagnosis and management of AIBDs in humans - to serve as a road map for veterinary dermatologists. AREAS COVERED: Recent findings include complement-independent pathways in the pathogenesis of bullous pemphigoid, as well as the role of desmoglein and desmocollin autoantibodies in inducing acantholysis. Systemic glucocorticoids are the mainstay of treatment for AIBDs in humans, yet their long-term use is associated with severe adverse effects and complications, thereby limiting their use. Therefore, researchers have been exploring new and safer alternative therapeutic options for human AIBDs such as anti-CD20 monoclonal antibodies (Rituximab), Bruton's tyrosine kinase inhibitors (BTKi) and neonatal Fc receptor (FcRn) blockers. EXPERT OPINION: Randomised controlled trial (RCT) level evidence show that Rituximab and short-course GC regimes are more effective and safer than traditional GC treatment for human AIBDs. FcRn blockers such as SYNT001 have shown positive results in preliminary phase 2 clinical trials for treatment of human pemphigus; further trials are required. Rilzabrutinib (PRN1008), an orally administered BTKi, has recently completed phase 2 trials in pemphigus and is in a phase 3 RCT in humans.
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Affiliation(s)
| | - Dedee F Murrell
- University of New South Wales, Sydney, Australia.,Department of Dermatology, St George Hospital, Sydney, Australia.,The George Institute for Global Health, Sydney, Australia
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18
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Bugter O, Li Y, Wolters AH, Agrawal V, Dravid A, Chang A, Hardillo J, Giepmans BN, Baatenburg de Jong RJ, Amelink A, Backman V, Robinson DJ. Early Upper Aerodigestive Tract Cancer Detection Using Electron Microscopy to Reveal Chromatin Packing Alterations in Buccal Mucosa Cells. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2021; 27:878-888. [PMID: 34108070 PMCID: PMC8939050 DOI: 10.1017/s1431927621000507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A profound characteristic of field cancerization is alterations in chromatin packing. This study aimed to quantify these alterations using electron microscopy image analysis of buccal mucosa cells of laryngeal, esophageal, and lung cancer patients. Analysis was done on normal-appearing mucosa, believed to be within the cancerization field, and not tumor itself. Large-scale electron microscopy (nanotomy) images were acquired of cancer patients and controls. Within the nuclei, the chromatin packing of euchromatin and heterochromatin was characterized. Furthermore, the chromatin organization was quantified through chromatin packing density scaling. A significant difference was found between the cancer and control groups in the chromatin packing density scaling parameter for length scales below the optical diffraction limit (200 nm) in both the euchromatin (p = 0.002) and the heterochromatin (p = 0.006). The chromatin packing scaling analysis also indicated that the chromatin organization of cancer patients deviated significantly from the control group. They might allow for novel strategies for cancer risk stratification and diagnosis with high sensitivity. This could aid clinicians in personalizing screening strategies for high-risk patients and follow-up strategies for treated cancer patients.
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Affiliation(s)
- Oisín Bugter
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
- Center for Optical Diagnostics and Therapy, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
| | - Yue Li
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Anouk H.G. Wolters
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, the Netherlands
| | - Vasundhara Agrawal
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Amil Dravid
- Department of Electrical Engineering and Computer Science, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Andrew Chang
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Jose Hardillo
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
| | - Ben N.G. Giepmans
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, the Netherlands
| | - Robert J. Baatenburg de Jong
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
| | - Arjen Amelink
- Department of Optics, the Netherlands Organization for Applied Scientific Research (TNO), Stieltjesweg 1, 2628 CK Delft, the Netherlands
- Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands
| | - Vadim Backman
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Dominic J. Robinson
- Department of Otorhinolaryngology and Head and Neck Surgery, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
- Center for Optical Diagnostics and Therapy, Erasmus MC Cancer Institute, Dr. Molewaterplein 40, Postbus 2040, 3000 CA Rotterdam, the Netherlands
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Dittmayer C, Goebel HH, Heppner FL, Stenzel W, Bachmann S. Preparation of Samples for Large-Scale Automated Electron Microscopy of Tissue and Cell Ultrastructure. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2021; 27:815-827. [PMID: 34266508 DOI: 10.1017/s1431927621011958] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Manual selection of targets in experimental or diagnostic samples by transmission electron microscopy (TEM), based on single overview and detail micrographs, has been time-consuming and susceptible to bias. Substantial information and throughput gain may now be achieved by the automated acquisition of virtually all structures in a given EM section. Resulting datasets allow the convenient pan-and-zoom examination of tissue ultrastructure with preserved microanatomical orientation. The technique is, however, critically sensitive to artifacts in sample preparation. We, therefore, established a methodology to prepare large-scale digitization samples (LDS) designed to acquire entire sections free of obscuring flaws. For evaluation, we highlight the supreme performance of scanning EM in transmission mode compared with other EM technology. The use of LDS will substantially facilitate access to EM data for a broad range of applications.
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Affiliation(s)
- Carsten Dittmayer
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neuropathology, Charitéplatz 1, 10117Berlin, Germany
| | - Hans-Hilmar Goebel
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neuropathology, Charitéplatz 1, 10117Berlin, Germany
- Johannes-Guttenberg University, Department of Neuropathology, Langenbeckstraße 1, 55122Mainz, Germany
| | - Frank L Heppner
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neuropathology, Charitéplatz 1, 10117Berlin, Germany
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Neurocure Cluster of Excellence, Charitéplatz 1, 10117Berlin, Germany
- German Center for Neurodegenerative Diseases (DZNE) Berlin, Berlin, Germany
| | - Werner Stenzel
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neuropathology, Charitéplatz 1, 10117Berlin, Germany
| | - Sebastian Bachmann
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Functional Anatomy, Charitéplatz 1, 10117Berlin, Germany
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20
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Nijholt KT, Meems LMG, Ruifrok WPT, Maass AH, Yurista SR, Pavez-Giani MG, Mahmoud B, Wolters AHG, van Veldhuisen DJ, van Gilst WH, Silljé HHW, de Boer RA, Westenbrink BD. The erythropoietin receptor expressed in skeletal muscle is essential for mitochondrial biogenesis and physiological exercise. Pflugers Arch 2021; 473:1301-1313. [PMID: 34142210 PMCID: PMC8302562 DOI: 10.1007/s00424-021-02577-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/16/2021] [Accepted: 05/05/2021] [Indexed: 12/13/2022]
Abstract
Erythropoietin (EPO) is a haematopoietic hormone that regulates erythropoiesis, but the EPO-receptor (EpoR) is also expressed in non-haematopoietic tissues. Stimulation of the EpoR in cardiac and skeletal muscle provides protection from various forms of pathological stress, but its relevance for normal muscle physiology remains unclear. We aimed to determine the contribution of the tissue-specific EpoR to exercise-induced remodelling of cardiac and skeletal muscle. Baseline phenotyping was performed on left ventricle and m. gastrocnemius of mice that only express the EpoR in haematopoietic tissues (EpoR-tKO). Subsequently, mice were caged in the presence or absence of a running wheel for 4 weeks and exercise performance, cardiac function and histological and molecular markers for physiological adaptation were assessed. While gross morphology of both muscles was normal in EpoR-tKO mice, mitochondrial content in skeletal muscle was decreased by 50%, associated with similar reductions in mitochondrial biogenesis, while mitophagy was unaltered. When subjected to exercise, EpoR-tKO mice ran slower and covered less distance than wild-type (WT) mice (5.5 ± 0.6 vs. 8.0 ± 0.4 km/day, p < 0.01). The impaired exercise performance was paralleled by reductions in myocyte growth and angiogenesis in both muscle types. Our findings indicate that the endogenous EPO-EpoR system controls mitochondrial biogenesis in skeletal muscle. The reductions in mitochondrial content were associated with reduced exercise capacity in response to voluntary exercise, supporting a critical role for the extra-haematopoietic EpoR in exercise performance.
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Affiliation(s)
- Kirsten T Nijholt
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Laura M G Meems
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Willem P T Ruifrok
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Alexander H Maass
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Salva R Yurista
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Mario G Pavez-Giani
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Belend Mahmoud
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Anouk H G Wolters
- Department of Cell Biology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands
| | - Dirk J van Veldhuisen
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Wiek H van Gilst
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Herman H W Silljé
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - Rudolf A de Boer
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands
| | - B Daan Westenbrink
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, HPC AB31, 9700 RB, P.O. Box 30.001, Groningen, The Netherlands.
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21
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Vermeer MC, Bolling MC, Bliley JM, Gomez KFA, Pavez-Giani MG, Kramer D, Romero-Herrera PH, Westenbrink BD, Diercks GF, van den Berg MP, Feinberg AW, Silljé HH, van der Meer P. Gain-of-function mutation in ubiquitin-ligase KLHL24 causes desmin degradation and dilatation in hiPSC-derived engineered heart tissues. J Clin Invest 2021; 131:140615. [PMID: 34292882 PMCID: PMC8409593 DOI: 10.1172/jci140615] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 07/08/2021] [Indexed: 12/30/2022] Open
Abstract
The start codon c.1A>G mutation in KLHL24, encoding ubiquitin-ligase KLHL24, results in the loss of 28 N-terminal amino acids (KLHL24-ΔN28) by skipping the initial start codon. In skin, KLHL24-ΔN28 leads to gain of function, excessively targeting intermediate filament keratin-14 for proteasomal degradation, ultimately causing epidermolysis bullosa simplex (EBS). The majority of these EBS-patients are also diagnosed with dilated cardiomyopathy (DCM), but the pathological mechanism in the heart is unknown. As desmin is the cardiac homologue of keratin-14, we hypothesized that KLHL24-ΔN28 leads to excessive degradation of desmin, resulting in DCM. Dynamically loaded engineered heart tissues (dyn-EHTs) were generated from human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes from two patients and three (non)familial controls. Ten-fold lower desmin protein levels were observed in patient-derived dyn-EHTs, in line with diminished desmin levels detected in patients' explanted heart. This was accompanied by tissue dilatation, impaired mitochondrial function, decreased force values and increased cardiomyocyte stress. HEK293 transfection studies confirmed KLHL24-mediated desmin degradation. KLHL24 RNA interference or direct desmin overexpression recovered desmin protein levels, restoring morphology and function in patient-derived dyn-EHTs. To conclude, presence of KLHL24-ΔN28 in cardiomyocytes leads to excessive degradation of desmin, affecting tissue morphology and function, that can be prevented by restoring desmin protein levels.
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Affiliation(s)
| | - Maria C. Bolling
- Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Jacqueline M. Bliley
- Department of Biomedical Engineering, Department of Materials Science & Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | | | | | - Duco Kramer
- Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | | | | | - Gilles F.H. Diercks
- Department of Pathology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | | | - Adam W. Feinberg
- Department of Biomedical Engineering, Department of Materials Science & Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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22
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Siegert E, Uruha A, Goebel HH, Preuße C, Casteleyn V, Kleefeld F, Alten R, Burmester GR, Schneider U, Höppner J, Hahn K, Dittmayer C, Stenzel W. Systemic sclerosis-associated myositis features minimal inflammation and characteristic capillary pathology. Acta Neuropathol 2021; 141:917-927. [PMID: 33864496 PMCID: PMC8113184 DOI: 10.1007/s00401-021-02305-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/27/2021] [Accepted: 03/28/2021] [Indexed: 12/11/2022]
Abstract
Systemic sclerosis represents a chronic connective tissue disease featuring fibrosis, vasculopathy and autoimmunity, affecting skin, multiple internal organs, and skeletal muscles. The vasculopathy is considered obliterative, but its pathogenesis is still poorly understood. This may partially be due to limitations of conventional transmission electron microscopy previously being conducted only in single patients. The aim of our study was therefore to precisely characterize immune inflammatory features and capillary morphology of systemic sclerosis patients suffering from muscle weakness. In this study, we identified 18 individuals who underwent muscle biopsy because of muscle weakness and myalgia in a cohort of 367 systemic sclerosis patients. We performed detailed conventional and immunohistochemical analysis and large-scale electron microscopy by digitizing entire sections for in-depth ultrastructural analysis. Muscle biopsies of 12 of these 18 patients (67%) presented minimal features of myositis but clear capillary alteration, which we termed minimal myositis with capillary pathology (MMCP). Our study provides novel findings in systemic sclerosis-associated myositis. First, we identified a characteristic and specific morphological pattern termed MMCP in 67% of the cases, while the other 33% feature alterations characteristic of other overlap syndromes. This is also reflected by a relatively homogeneous clinical picture among MMCP patients. They have milder disease with little muscle weakness and a low prevalence of interstitial lung disease (20%) and diffuse skin involvement (10%) and no cases of either pulmonary arterial hypertension or renal crisis. Second, large-scale electron microscopy, introducing a new level of precision in ultrastructural analysis, revealed a characteristic capillary morphology with basement membrane thickening and reduplications, endothelial activation and pericyte proliferation. We provide open-access pan-and-zoom analysis to our datasets, enabling critical discussion and data mining. We clearly highlight characteristic capillary pathology in skeletal muscles of systemic sclerosis patients.
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Affiliation(s)
- Elise Siegert
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
- Berlin Institute of Health, Anna-Louisa-Karsch-Str. 2, 10178, Berlin, Germany
| | - Akinori Uruha
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Charitéplatz 1, 10117, Berlin, Germany
| | - Hans-Hilmar Goebel
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Charitéplatz 1, 10117, Berlin, Germany
| | - Corinna Preuße
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Charitéplatz 1, 10117, Berlin, Germany
| | - Vincent Casteleyn
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Felix Kleefeld
- Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Rieke Alten
- Schlosspark-Klinik, Heubnerweg 2, 14059, Berlin, Germany
| | - Gerd R Burmester
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Udo Schneider
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Jakob Höppner
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Kathrin Hahn
- Department of Neurology and Experimental Neurology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Carsten Dittmayer
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Charitéplatz 1, 10117, Berlin, Germany
| | - Werner Stenzel
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Charitéplatz 1, 10117, Berlin, Germany.
- Leibniz ScienceCampus Chronic Inflammation, 10117, Berlin, Germany.
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23
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Abstract
ABSTRACT Pemphigus vulgaris (PV) is a severe, potentially life-threatening autoimmune blistering disease, which is common in India. Although there is abundant literature on clinical and immunologic features, comprehensive studies on its histopathology are lacking. The aim of this study was to describe the histopathologic and immunofluorescence features as well as discuss various diagnostic pitfalls of PV. Histopathologic and immunofluorescence (DIF/IIF) findings were reviewed for 169 biopsies from 2007 to 2017 (11 years). The 169 samples included 152 skin, 16 oral mucosal, and 1 corneal biopsy. Maximum prevalence was noted in the fifth decade (57%) with a slight male preponderance. Vesicles were seen in 149 cases (88%), the level of which was suprabasal in 91(61%) and both suprabasal and intraepidermal in 50 cases (33.5%). Acantholytic cells were present in 142 cases (95%). Acantholytic keratinocytes showed rounded and polygonal acantholysis. 86 (51%) cases showed evidence of regeneration. Adnexal involvement was seen in 92 cases, commonest in the hair follicles. Unusual histologic findings included: intraepidermal bulla, absence of dermal inflammation, free floating hair shafts, multinucleated epithelial cells, eosinophil predominance; all of which are discussed. DIF was performed in 166 cases, of which 163 were positive (98%), and IgG was the commonest immunoreactant (96%). IIF was performed in 11 cases, of which 9 cases were positive for Dsg3. Although the diagnosis of PV rests on combined clinical, histologic, and IF features, histopathology as the sole means is also a powerful tool. It is important to be aware of the diagnostic pitfalls to optimize its utility.
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Affiliation(s)
- Anisha Manocha
- Department of Pathology, St. John's Medical College, Bangalore, India
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24
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de Vrij EL, Bouma HR, Goris M, Weerman U, de Groot AP, Kuipers J, Giepmans BNG, Henning RH. Reversible thrombocytopenia during hibernation originates from storage and release of platelets in liver sinusoids. J Comp Physiol B 2021; 191:603-615. [PMID: 33661336 PMCID: PMC8043940 DOI: 10.1007/s00360-021-01351-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 01/15/2021] [Accepted: 01/23/2021] [Indexed: 01/21/2023]
Abstract
Immobility is a risk factor for thrombosis due to low blood flow, which may result in activation of the coagulation system, recruitment of platelets and clot formation. Nevertheless, hibernating animals-who endure lengthy periods of immobility-do not show signs of thrombosis throughout or after hibernation. One of the adaptations of hemostasis in hibernators consists of a rapidly reversible reduction of the number of circulating platelets during torpor, i.e., the hibernation phase with reduction of metabolic rate, low blood flow and immobility. It is unknown whether these platelet dynamics in hibernating hamsters originate from storage and release, as suggested for ground squirrel, or from breakdown and de novo synthesis. A reduction in detaching forces due to low blood flow can induce reversible adhesion of platelets to the vessel wall, which is called margination. Here, we hypothesized that storage-and-release by margination to the vessel wall induces reversible thrombocytopenia in torpor. Therefore, we transfused labeled platelets in hibernating Syrian hamster (Mesocricetus auratus) and platelets were analyzed using flow cytometry and electron microscopy. The half-life of labeled platelets was extended from 20 to 30 h in hibernating animals compared to non-hibernating control hamsters. More than 90% of labeled platelets were cleared from the circulation during torpor, followed by emergence during arousal which supports storage-and-release to govern thrombocytopenia in torpor. Furthermore, the low number of immature platelets, plasma level of interleukin-1α and normal numbers of megakaryocytes in bone marrow make platelet synthesis or megakaryocyte rupture via interleukin-1α unlikely to account for the recovery of platelet counts upon arousal. Finally, using large-scale electron microscopy we revealed platelets to accumulate in liver sinusoids, but not in spleen or lung, during torpor. These results thus demonstrate that platelet dynamics in hibernation are caused by storage and release of platelets, most likely by margination to the vessel wall in liver sinusoids. Translating the molecular mechanisms that govern platelet retention in the liver, may be of major relevance for hemostatic management in (accidental) hypothermia and for the development of novel anti-thrombotic strategies.
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Affiliation(s)
- Edwin L de Vrij
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700 RB, Groningen, The Netherlands.
- Department of Plastic Surgery, University Medical Center Groningen, Groningen, the Netherlands.
| | - Hjalmar R Bouma
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700 RB, Groningen, The Netherlands
- Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Maaike Goris
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700 RB, Groningen, The Netherlands
| | - Ulrike Weerman
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700 RB, Groningen, The Netherlands
| | - Anne P de Groot
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700 RB, Groningen, The Netherlands
| | - Jeroen Kuipers
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Robert H Henning
- Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700 RB, Groningen, The Netherlands
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25
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Pirozzi NM, Kuipers J, Giepmans BNG. Sample preparation for energy dispersive X-ray imaging of biological tissues. Methods Cell Biol 2020; 162:89-114. [PMID: 33707024 DOI: 10.1016/bs.mcb.2020.10.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Traditional electron microscopy (EM) can be complemented with analytical EM to increase objective sample information enabling feature identification. Energy dispersive X-ray (EDX) imaging provides semi-quantitative elemental composition of the sample with high spatial resolution (~10nm) in ultrathin sections. However, EDX imaging of biological samples is still challenging as a routine method because many elements are at the detection limit for this technique. Moreover, samples undergo extensive preparation before analysis, which can introduce disruptive X-ray cross-talk or artifacts. EDX data can, for instance, be skewed by (i) osmium interference with endogenous phosphorus, (ii) chlorine present in EPON-embedded tissues, (iii) lead interference with endogenous sulfur, and (iv) potential spectral overlaps with grid material, contrast agents, and the in-microscope sample holder. Here, we highlight how to circumvent these potential pitfalls and outline how we approach sample preparation and analysis for detection of different elements of interest. Utilization of well-considered a priori sample preparation techniques will best ensure conclusive EDX experiments.
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Affiliation(s)
- Nicole M Pirozzi
- Department of Biomedical Sciences of Cells and Systems, Groningen, The Netherlands
| | - Jeroen Kuipers
- Department of Biomedical Sciences of Cells and Systems, Groningen, The Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, Groningen, The Netherlands.
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26
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Faber AIE, van der Zwaag M, Schepers H, Eggens-Meijer E, Kanon B, IJsebaart C, Kuipers J, Giepmans BNG, Freire R, Grzeschik NA, Rabouille C, Sibon OCM. Vps13 is required for timely removal of nurse cell corpses. Development 2020; 147:dev.191759. [PMID: 32994170 DOI: 10.1242/dev.191759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/15/2020] [Indexed: 12/25/2022]
Abstract
Programmed cell death and consecutive removal of cellular remnants is essential for development. During late stages of Drosophila melanogaster oogenesis, the small somatic follicle cells that surround the large nurse cells promote non-apoptotic nurse cell death, subsequently engulf them, and contribute to the timely removal of nurse cell corpses. Here, we identify a role for Vps13 in the timely removal of nurse cell corpses downstream of developmental programmed cell death. Vps13 is an evolutionarily conserved peripheral membrane protein associated with membrane contact sites and lipid transfer. It is expressed in late nurse cells, and persistent nurse cell remnants are observed when Vps13 is depleted from nurse cells but not from follicle cells. Microscopic analysis revealed enrichment of Vps13 in close proximity to the plasma membrane and the endoplasmic reticulum in nurse cells undergoing degradation. Ultrastructural analysis uncovered the presence of an underlying Vps13-dependent membranous structure in close association with the plasma membrane. The newly identified structure and function suggests the presence of a Vps13-dependent process required for complete degradation of bulky remnants of dying cells.
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Affiliation(s)
- Anita I E Faber
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Marianne van der Zwaag
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Hein Schepers
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Ellie Eggens-Meijer
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Bart Kanon
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Carmen IJsebaart
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Jeroen Kuipers
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Raimundo Freire
- Unidad de Investigación/FIISC, Hospital Universitario de Canarias, Ofra s/n, La Cuesta, 38320 San Cristóbal de La Laguna, Tenerife, Spain.,Instituto de Tecnologías Biomédicas, Universidad de La Laguna, 38200 San Cristóbal de La Laguna, Tenerife, Spain.,Facultad de Ciencias de la Salud, Universidad Fernando Pessoa Canarias, 35450 Las Palmas de Gran Canaria, Spain
| | - Nicola A Grzeschik
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
| | - Catherine Rabouille
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands.,Hubrecht Institute, University of Utrecht, 3584 CT, Utrecht, The Netherlands
| | - Ody C M Sibon
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, The University of Groningen, 9713 AV, Groningen, The Netherlands
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27
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Giannetti L, Murri Dello Diago A. Therapy of autoimmune mouth bullous disease: 2020 review. Dermatol Ther 2020; 34:e14376. [PMID: 33029891 DOI: 10.1111/dth.14376] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 09/28/2020] [Indexed: 11/30/2022]
Abstract
Most diseases of oral mucosa are either autoimmune in nature or are the results of immunologically mediated events. The diseases with autoimmune pathogenesis are namely pemphigus and pemphigoid; the oral involvement is frequent or regularly observed in these diseases. The treatments with traditional drugs or biologic agents or combinations of these molecules are employed in clinical practice. New therapeutic targets aim to provide new treatment strategies that may go beyond nonspecific immunosuppression.
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Affiliation(s)
- Luca Giannetti
- Dipartimento Chirurgico, Medico, Odontoiatrico E Di Scienze Morfologiche Con Interesse Trapiantologico, Oncologico E Di Medicina Rigenerativa, Universita' degli Studi di Modena e Reggio Emilia, Modena, Italy
| | - Alberto Murri Dello Diago
- Dipartimento Chirurgico, Medico, Odontoiatrico E Di Scienze Morfologiche Con Interesse Trapiantologico, Oncologico E Di Medicina Rigenerativa, Universita' degli Studi di Modena e Reggio Emilia, Modena, Italy
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28
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Petzl-Erler ML. Beyond the HLA polymorphism: A complex pattern of genetic susceptibility to pemphigus. Genet Mol Biol 2020; 43:e20190369. [PMID: 32639508 PMCID: PMC7341728 DOI: 10.1590/1678-4685-gmb-2019-0369] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 04/06/2020] [Indexed: 12/16/2022] Open
Abstract
Pemphigus is a group of autoimmune bullous skin diseases that result in
significant morbidity. As for other multifactorial autoimmune disorders,
environmental factors may trigger the disease in genetically susceptible
individuals. The goals of this review are to summarize the state of knowledge
about the genetic variation that may affect the susceptibility and pathogenesis
of pemphigus vulgaris and pemphigus foliaceus – both the endemic and the
sporadic forms –, to compare and discuss the possible meaning of the
associations reported, and to propose recommendations for new research
initiatives. Understanding how genetic variants translate into pathogenic
mechanisms and phenotypes remains a mystery for most of the polymorphisms that
contribute to disease susceptibility. However, genetic studies provide a strong
foundation for further developments in this field by generating testable
hypotheses. Currently, results still have limited influence on disease
prevention and prognosis, drug development, and clinical practice, although the
perspectives for future applications for the benefit of patients are
encouraging. Recommendations for the continued advancement of our understanding
as to the impact of genetic variation on pemphigus include these partially
overlapping goals: (1) Querying the functional effect of genetic variants on the
regulation of gene expression through their impact on the nucleotide sequence of
cis regulatory DNA elements such as promoters and enhancers, the splicing of
RNA, the structure of regulatory RNAs and proteins, binding of these regulatory
molecules to regulatory DNA elements, and alteration of epigenetic marks; (2)
identifying key cell types and cell states that are implicated in pemphigus
pathogenesis and explore their functional genomes; (3) integrating structural
and functional genomics data; (4) performing disease-progression longitudinal
studies to disclose the causal relationships between genetic and epigenetic
variation and intermediate disease phenotypes; (5) understanding the influence
of genetic and epigenetic variation in the response to treatment and the
severity of the disease; (6) exploring gene-gene and genotype-environment
interactions; (7) developing improved pemphigus-prone and non-prone animal
models that are appropriate for research about the mechanisms that link
genotypes to pemphigus. Achieving these goals will demand larger samples of
patients and controls and multisite collaborations.
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Affiliation(s)
- Maria Luiza Petzl-Erler
- Laboratório de Genética Molecular Humana, Departamento de Genética, Universidade Federal do Paraná, Curitiba, PR, Brazil
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29
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de Boer P, Pirozzi NM, Wolters AHG, Kuipers J, Kusmartseva I, Atkinson MA, Campbell-Thompson M, Giepmans BNG. Large-scale electron microscopy database for human type 1 diabetes. Nat Commun 2020; 11:2475. [PMID: 32424134 PMCID: PMC7235089 DOI: 10.1038/s41467-020-16287-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 04/23/2020] [Indexed: 01/13/2023] Open
Abstract
Autoimmune β-cell destruction leads to type 1 diabetes, but the pathophysiological mechanisms remain unclear. To help address this void, we created an open-access online repository, unprecedented in its size, composed of large-scale electron microscopy images ('nanotomy') of human pancreas tissue obtained from the Network for Pancreatic Organ donors with Diabetes (nPOD; www.nanotomy.org). Nanotomy allows analyses of complete donor islets with up to macromolecular resolution. Anomalies we found in type 1 diabetes included (i) an increase of 'intermediate cells' containing granules resembling those of exocrine zymogen and endocrine hormone secreting cells; and (ii) elevated presence of innate immune cells. These are our first results of mining the database and support recent findings that suggest that type 1 diabetes includes abnormalities in the exocrine pancreas that may induce endocrine cellular stress as a trigger for autoimmunity.
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Affiliation(s)
- Pascal de Boer
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Nicole M Pirozzi
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Anouk H G Wolters
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jeroen Kuipers
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Irina Kusmartseva
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida Diabetes Institute, Gainesville, FL, USA
| | - Mark A Atkinson
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida Diabetes Institute, Gainesville, FL, USA
- Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Martha Campbell-Thompson
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida Diabetes Institute, Gainesville, FL, USA
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
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30
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Hammers CM, Stanley JR. Recent Advances in Understanding Pemphigus and Bullous Pemphigoid. J Invest Dermatol 2020; 140:733-741. [DOI: 10.1016/j.jid.2019.11.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 10/29/2019] [Accepted: 11/01/2019] [Indexed: 12/11/2022]
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31
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Rempel IL, Popken P, Ghavami A, Mishra A, Hapsari RA, Wolters AHG, Veldsink AC, Klaassens M, Meinema AC, Poolman B, Giepmans BNG, Onck PR, Steen A, Veenhoff LM. Flexible and Extended Linker Domains Support Efficient Targeting of Heh2 to the Inner Nuclear Membrane. Structure 2020; 28:185-195.e5. [PMID: 31806352 DOI: 10.1016/j.str.2019.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 08/09/2019] [Accepted: 11/08/2019] [Indexed: 10/25/2022]
Abstract
The nuclear pore complex (NPC) is embedded in the nuclear envelope and forms the main gateway to the nuclear interior including the inner nuclear membrane (INM). Two INM proteins in yeast are selectively imported. Their sorting signals consist of a nuclear localization signal, separated from the transmembrane domain by a long intrinsically disordered (ID) linker. We used computational models to predict the dynamic conformations of ID linkers and analyzed the INM targeting efficiency of proteins with linker regions with altered Stokes radii and decreased flexibilities. We find that flexibility, Stokes radius, and the frequency at which the linkers are at an extended end-to-end distance larger than 25 nm are good predictors for the targeting of the proteins. The data are consistent with a transport mechanism in which INM targeting of Heh2 is dependent on an ID linker that facilitates the crossing of the approximately 25-nm thick NPC scaffold.
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Affiliation(s)
- Irina L Rempel
- European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands
| | - Petra Popken
- European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands; Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands; Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Ali Ghavami
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Ankur Mishra
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Rizqiya A Hapsari
- European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands
| | - Anouk H G Wolters
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands
| | - Annemiek C Veldsink
- European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands
| | - Marindy Klaassens
- European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands
| | - Anne C Meinema
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Bert Poolman
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands; Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands
| | - Patrick R Onck
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, Groningen 9747 AG, The Netherlands.
| | - Anton Steen
- European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands.
| | - Liesbeth M Veenhoff
- European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, Groningen 9713 AV, Netherlands.
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32
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Kuipers J, Giepmans BNG. Neodymium as an alternative contrast for uranium in electron microscopy. Histochem Cell Biol 2020; 153:271-277. [PMID: 32008069 PMCID: PMC7160090 DOI: 10.1007/s00418-020-01846-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2020] [Indexed: 11/28/2022]
Abstract
Uranyl acetate is the standard contrasting agent in electron microscopy (EM), but it is toxic and radioactive. We reasoned neodymium acetate might substitute uranyl acetate as a contrasting agent, and we find that neodymium acetate indeed can replace uranyl acetate in several routine applications. Since neodymium acetate is not toxic, not radioactive and easy to use, we foresee neodymium will replace uranyl in many EM sample preparation applications worldwide.
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Affiliation(s)
- Jeroen Kuipers
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Ben N G Giepmans
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
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33
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Egu DT, Kugelmann D, Waschke J. Role of PKC and ERK Signaling in Epidermal Blistering and Desmosome Regulation in Pemphigus. Front Immunol 2019; 10:2883. [PMID: 31867019 PMCID: PMC6910072 DOI: 10.3389/fimmu.2019.02883] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/25/2019] [Indexed: 01/27/2023] Open
Abstract
Desmosomes reinforce cohesion of epithelial cells at the interface between adjacent cells. They include the cadherin-type adhesion molecules desmoglein 1 (Dsg1) and Dsg3. Pemphigus vulgaris (PV) is an autoimmune disease in which circulating autoantibodies (PV-IgG) targeting Dsg1 and 3 cause characteristic epidermal blister formation. It has been shown that PV-IgG binding induced activation of kinases such as ERK and PKC, and inhibition of these signaling pathways prevented loss of cell cohesion in cell cultures. However, the role of Erk and PKC in blister formation and regulation of desmosome ultrastructure in human skin are unknown. Accordingly, we assessed the role of PKC and ERK signaling pathways in blister formation and regulation of desmosome ultrastructure in human epidermis. Here we performed electron microscopy analyses using human skin explants injected with PV-IgG together with inhibitors for PKC or ERK signaling. Inhibition of PKC was not effective to prevent suprabasal blister formation or ultrastructural alterations of desmosomes. In contrast, inhibition of ERK signaling significantly ameliorated blister formation and decrease in the number of desmosomes whereas shortening and splitting of desmosomes and keratin filament insertion were not different from samples treated with PV-IgG alone. However, apical desmosomes between basal and suprabasal cells remained unaltered when ERK signaling was inhibited. Therefore, our results show that inhibition of ERK but not PKC signaling appears to be effective to ameliorate blistering and alterations of desmosome ultrastructure triggered by PV-IgG in human skin.
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Affiliation(s)
- Desalegn Tadesse Egu
- Chair of Vegetative Anatomy, Faculty of Medicine, Institute of Anatomy, LMU Munich, Munich, Germany
| | - Daniela Kugelmann
- Chair of Vegetative Anatomy, Faculty of Medicine, Institute of Anatomy, LMU Munich, Munich, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Faculty of Medicine, Institute of Anatomy, LMU Munich, Munich, Germany
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34
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Yang M, Wu H, Zhao M, Chang C, Lu Q. The pathogenesis of bullous skin diseases. J Transl Autoimmun 2019; 2:100014. [PMID: 32743502 PMCID: PMC7388362 DOI: 10.1016/j.jtauto.2019.100014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/14/2019] [Accepted: 08/21/2019] [Indexed: 01/13/2023] Open
Abstract
Bullous skin diseases are a group of dermatoses characterized by blisters and bullae in the skin and mucous membranes. The etiology and pathogenesis of bullous skin diseases are not completely clear. The most common are pemphigus and bullous pemphigoid (BP). Autoantibodies play critical roles in their pathogenesis. Abnormalities in the adhesion between keratinocytes in patients with pemphigus leads to acantholysis and formation of intra-epidermal blisters. Anti-desmoglein autoantibodies are present both in the circulation and skin lesions of patients with pemphigus. The deficient adhesion of keratinocytes to the basement membrane in BP patients gives rise to subepidermal blisters. Autoantibodies against the components of hemidesmosome can be detected in BP patients. Many novel therapeutics based on knowledge of the pathogenesis have emerged in recent years.
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Affiliation(s)
- Miao Yang
- Department of Dermatology, Hunan Key Laboratory of Medical Epigenomics, The second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, PR China
| | - Haijing Wu
- Department of Dermatology, Hunan Key Laboratory of Medical Epigenomics, The second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, PR China
| | - Ming Zhao
- Department of Dermatology, Hunan Key Laboratory of Medical Epigenomics, The second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, PR China
| | - Christopher Chang
- Division of Rheumatology, Allergy and Clinical Immunology, University of California, Davis, CA, 95616, USA
- Division of Pediatric Immunology and Allergy, Joe DiMaggio Children’s Hospital, Hollywood, FL, 33021, USA
| | - Qianjin Lu
- Department of Dermatology, Hunan Key Laboratory of Medical Epigenomics, The second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, PR China
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35
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Oktarina DAM, Sokol E, Kramer D, Jonkman MF, Pas HH. Endocytosis of IgG, Desmoglein 1, and Plakoglobin in Pemphigus Foliaceus Patient Skin. Front Immunol 2019; 10:2635. [PMID: 31781120 PMCID: PMC6861377 DOI: 10.3389/fimmu.2019.02635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 10/24/2019] [Indexed: 01/29/2023] Open
Abstract
Pemphigus foliaceus (PF) is one of the two main forms of pemphigus and is characterized by circulating IgG to the desmosomal cadherin desmoglein 1 (DSG1) and by subcorneal blistering of the skin. The pathomechanism of blister formation in PF is unknown. Previously we have shown that PF IgG induces aggregation of DSG1, plakoglobin (PG), and IgG outside of desmosomes, what in immunofluorescence of PF patient skin visualizes as a granular IgG deposition pattern with a limited number of coarse IgG aggregates between cells. Here we have investigated the fate of these aggregates in skin and found that these are cleared by endocytosis. We performed double immunofluorescence staining on snap-frozen skin biopsies of six PF patients for the following molecules: IgG, the desmosomal proteins DSG1 and DSG3, desmocollins 1 and 3, PG, desmoplakin and plakophilin 3, and for the endosomal marker early endosomal antigen 1 and the lysosomal markers cathepsin D and lysosomal-associated membrane protein 1. Endosomes were present in all cells but did not make contact with the aggregates in the basal and suprabasal layers. In the higher layers they moored to the aggregates, often symmetrically from two adjacent cells, and IgG, DSG1, and PG were taken up. Finally these endosomes became localized perinuclear. Endocytosis was only observed in perilesional or lesional skin but not in non-lesional skin. Older immunoelectron microscopic studies have suggested that in PF skin endocytosis of detached desmosomes takes place but we found no other desmosomal proteins to be present in these endosomes. Double staining with cathepsin D and LAMP-1 revealed no overlap with IgG, DSG1, or PG suggesting that lysosomes have no role in the clearing process. Collectively, our results show that endocytosis is part of the pathogenic process in PF but that no detached desmosomes are taken up but instead the deposited IgG is taken up together with DSG1 and PG.
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Affiliation(s)
- Dyah A M Oktarina
- Department of Dermatology, Centre for Blistering Diseases, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands.,Department of Dermatology and Venereology, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Ena Sokol
- Department of Dermatology, Centre for Blistering Diseases, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands
| | - Duco Kramer
- Department of Dermatology, Centre for Blistering Diseases, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands
| | - Marcel F Jonkman
- Department of Dermatology, Centre for Blistering Diseases, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands
| | - Hendri H Pas
- Department of Dermatology, Centre for Blistering Diseases, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands
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Bumiller-Bini V, Cipolla GA, Spadoni MB, Augusto DG, Petzl-Erler ML, Beltrame MH, Boldt ABW. Condemned or Not to Die? Gene Polymorphisms Associated With Cell Death in Pemphigus Foliaceus. Front Immunol 2019; 10:2416. [PMID: 31681304 PMCID: PMC6813369 DOI: 10.3389/fimmu.2019.02416] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 09/26/2019] [Indexed: 12/13/2022] Open
Abstract
Pemphigus foliaceus (PF) is an autoimmune blistering skin disease that occurs sporadically across the globe and is endemic in Brazil. Keratinocyte adhesion loss (acantholysis) is associated with high levels of anti-desmoglein 1 IgG autoantibodies, but the role of cell death is poorly understood in PF. Current evidence disqualifies apoptosis as the major cell death mechanism and no other process has yet been investigated. To approach the role of variation in genes responsible for cell death pathways in pemphigus susceptibility, we systematically investigated the frequencies of 1,167 polymorphisms from genes encoding products of all 12 well-established cell death cascades (intrinsic and extrinsic apoptosis, necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic, NETotic, lysosome-dependent, autophagy-dependent, and immunogenic). By multivariate logistic regression, we compared allelic and genotypic frequencies of 227 PF patients and 194 controls obtained by microarray hybridization. We found 10 variants associated with PF (p < 0.005), belonging to six cell death pathways: apoptosis (TNF, TRAF2, CD36, and PAK2), immunogenic cell death (EIF2AK3, CD47, and SIRPA), necroptosis (TNF and TRAF2), necrosis (RAPGEF3), parthanatos (HK1), and pyroptosis (PRKN). Five polymorphisms were associated with susceptibility: TNF rs1800630*A (OR = 1.9, p = 0.0003), CD36 rs4112274*T (OR = 2.14, p = 0.0015), CD47 rs12695175*G (OR = 1.77, p = 0.0043), SIRPA rs6075340*A/A (OR = 2.75, p = 0.0009), and HK1 rs7072268*T (OR = 1.48, p = 0.0045). Other five variants were associated with protection: TRAF2 rs10781522*G (OR = 0.64, p = 0.0014), PAK2 rs9325377*A/A (OR = 0.48, p = 0.0023), EIF2AK3 rs10167879*T (OR = 0.48, p = 0.0007), RAPGEF3 rs10747521*A/A (OR = 0.42, p = 0.0040), and PRKN rs9355950*C (OR = 0.57, p = 0.0004). Through functional annotation, we found that all associated alleles, with the exception of PRKN rs9355950*C, were previously associated with differential gene expression levels in healthy individuals (mostly in skin and peripheral blood). Further functional validation of these genetic associations may contribute to the understanding of PF etiology and to the development of new drugs and therapeutic regimens for the disease.
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Affiliation(s)
- Valéria Bumiller-Bini
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba, Brazil
| | - Gabriel Adelman Cipolla
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba, Brazil
| | - Mariana Basso Spadoni
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba, Brazil
| | - Danillo Gardenal Augusto
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
| | - Maria Luiza Petzl-Erler
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba, Brazil
| | - Marcia Holsbach Beltrame
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba, Brazil
| | - Angelica Beate Winter Boldt
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná, Curitiba, Brazil
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Abstract
Pemphigus consists of a group of rare and severe autoimmune blistering diseases mediated by pathogenic autoantibodies mainly directed against two desmosomal adhesion proteins, desmoglein (Dsg)1 and Dsg3 (also known as DG1 and DG3), which are present in the skin and surface-close mucosae. The binding of autoantibodies to Dsg proteins induces a separation of neighbouring keratinocytes, in a process known as acantholysis. The two main pemphigus variants are pemphigus vulgaris, which often originates with painful oral erosions, and pemphigus foliaceus, which is characterised by exclusive skin lesions. Pemphigus is diagnosed on the basis of either IgG or complement component 3 deposits (or both) at the keratinocyte cell membrane, detected by direct immunofluorescence microscopy of a perilesional biopsy, with serum anti-Dsg1 or anti-Dsg3 antibodies (or both) detected by ELISA. Corticosteroids are the therapeutic mainstay, which have recently been complemented by the anti-CD20 antibody rituximab in moderate and severe disease. Rituximab induces complete remission off therapy in 90% of patients, despite rapid tapering of corticosteroids, thus allowing for a major corticosteroid-sparing effect and a halved number of adverse events related to corticosteroids.
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Affiliation(s)
- Enno Schmidt
- Department of Dermatology, University of Lübeck, Lübeck, Germany; Lübeck Institute for Experimental Dermatology, University of Lübeck, Lübeck, Germany.
| | - Michael Kasperkiewicz
- Department of Dermatology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Pascal Joly
- Department of Dermatology, Rouen University Hospital, Rouen, France; INSERM Unit 2345, French Reference Center for Autoimmune Bullous Diseases, Normandy University, Rouen, France
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Egu D, Sigmund A, Schmidt E, Spindler V, Walter E, Waschke J. A new
ex vivo
human oral mucosa model reveals that p38
MAPK
inhibition is not effective in preventing autoantibody‐induced mucosal blistering in pemphigus. Br J Dermatol 2019; 182:987-994. [DOI: 10.1111/bjd.18237] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2019] [Indexed: 02/06/2023]
Affiliation(s)
- D.T. Egu
- Chair of Vegetative Anatomy Institute of Anatomy Faculty of Medicine LMU Munich Germany
| | - A.M. Sigmund
- Chair of Vegetative Anatomy Institute of Anatomy Faculty of Medicine LMU Munich Germany
| | - E. Schmidt
- Lübeck Institute of Experimental Dermatology University of Lübeck LübeckGermany
- Department of Dermatology, Allergology and Venereology University of Lübeck Lübeck Germany
| | - V. Spindler
- Chair of Vegetative Anatomy Institute of Anatomy Faculty of Medicine LMU Munich Germany
- Department of Biomedicine University of Basel Basel Switzerland
| | - E. Walter
- Chair of Vegetative Anatomy Institute of Anatomy Faculty of Medicine LMU Munich Germany
| | - J. Waschke
- Chair of Vegetative Anatomy Institute of Anatomy Faculty of Medicine LMU Munich Germany
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39
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Fuchs M, Foresti M, Radeva MY, Kugelmann D, Keil R, Hatzfeld M, Spindler V, Waschke J, Vielmuth F. Plakophilin 1 but not plakophilin 3 regulates desmoglein clustering. Cell Mol Life Sci 2019; 76:3465-3476. [PMID: 30949721 PMCID: PMC11105395 DOI: 10.1007/s00018-019-03083-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 02/15/2019] [Accepted: 03/25/2019] [Indexed: 12/25/2022]
Abstract
Plakophilins (Pkp) are desmosomal plaque proteins crucial for desmosomal adhesion and participate in the regulation of desmosomal turnover and signaling. However, direct evidence that Pkps regulate clustering and molecular binding properties of desmosomal cadherins is missing. Here, keratinocytes lacking either Pkp1 or 3 in comparison to wild type (wt) keratinocytes were characterized with regard to their desmoglein (Dsg) 1- and 3-binding properties and their capability to induce Dsg3 clustering. As revealed by atomic force microscopy (AFM), both Pkp-deficient keratinocyte cell lines showed reduced membrane availability and binding frequency of Dsg1 and 3 at cell borders. Extracellular crosslinking and AFM cluster mapping demonstrated that Pkp1 but not Pkp3 is required for Dsg3 clustering. Accordingly, Dsg3 overexpression reconstituted cluster formation in Pkp3- but not Pkp1-deficient keratinocytes as shown by AFM and STED experiments. Taken together, these data demonstrate that both Pkp1 and 3 regulate Dsg membrane availability, whereas Pkp1 but not Pkp3 is required for Dsg3 clustering.
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Affiliation(s)
- Michael Fuchs
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Marco Foresti
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Mariya Y Radeva
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Daniela Kugelmann
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Rene Keil
- Division of Pathobiochemistry, Institute of Molecular Medicine, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Mechthild Hatzfeld
- Division of Pathobiochemistry, Institute of Molecular Medicine, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Volker Spindler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Jens Waschke
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany.
| | - Franziska Vielmuth
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany.
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40
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Didona D, Maglie R, Eming R, Hertl M. Pemphigus: Current and Future Therapeutic Strategies. Front Immunol 2019; 10:1418. [PMID: 31293582 PMCID: PMC6603181 DOI: 10.3389/fimmu.2019.01418] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Accepted: 06/05/2019] [Indexed: 12/16/2022] Open
Abstract
Pemphigus encompasses a heterogeneous group of autoimmune blistering diseases, which affect both mucous membranes and the skin. The disease usually runs a chronic-relapsing course, with a potentially devastating impact on the patients' quality of life. Pemphigus pathogenesis is related to IgG autoantibodies targeting various adhesion molecules in the epidermis, including desmoglein (Dsg) 1 and 3, major components of desmosomes. The pathogenic relevance of such autoantibodies has been largely demonstrated experimentally. IgG autoantibody binding to Dsg results in loss of epidermal keratinocyte adhesion, a phenomenon referred to as acantholysis. This in turn causes intra-epidermal blistering and the clinical appearance of flaccid blisters and erosions at involved sites. Since the advent of glucocorticoids, the overall prognosis of pemphigus has largely improved. However, mortality persists elevated, since long-term use of high dose corticosteroids and adjuvant steroid-sparing immunosuppressants portend a high risk of serious adverse events, especially infections. Recently, rituximab, a chimeric anti CD20 monoclonal antibody which induces B-cell depletion, has been shown to improve patients' survival, as early rituximab use results in higher disease remission rates, long term clinical response and faster prednisone tapering compared to conventional immunosuppressive therapies, leading to its approval as a first line therapy in pemphigus. Other anti B-cell therapies targeting B-cell receptor or downstream molecules are currently tried in clinical studies. More intriguingly, a preliminary study in a preclinical mouse model of pemphigus has shown promise regarding future therapeutic application of Chimeric Autoantibody Receptor T-cells engineered using Dsg domains to selectively target autoreactive B-cells. Conversely, previous studies from our group have demonstrated that B-cell depletion in pemphigus resulted in secondary impairment of T-cell function; this may account for the observed long-term remission following B-cell recovery in rituximab treated patients. Likewise, our data support the critical role of Dsg-specific T-cell clones in orchestrating the inflammatory response and B-cell activation in pemphigus. Monitoring autoreactive T-cells in patients may indeed provide further information on the role of these cells, and would be the starting point for designating therapies aimed at restoring the lost immune tolerance against Dsg. The present review focuses on current advances, unmet challenges and future perspectives of pemphigus management.
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Affiliation(s)
- Dario Didona
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany
| | - Roberto Maglie
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany.,Surgery and Translational Medicine, Section of Dermatology, University of Florence, Florence, Italy.,Section of Dermatology, Departement of Health Sciences, University of Florence, Florence, Italy
| | - Rüdiger Eming
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany
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41
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Dittmayer C, Völcker E, Wacker I, Schröder RR, Bachmann S. Modern field emission scanning electron microscopy provides new perspectives for imaging kidney ultrastructure. Kidney Int 2019; 94:625-631. [PMID: 30143069 DOI: 10.1016/j.kint.2018.05.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 04/09/2018] [Accepted: 05/17/2018] [Indexed: 11/30/2022]
Abstract
Recent progress in electron microscopy (EM) techniques has opened new pathways to study renal tissue in research and pathology. Modern field emission scanning EM may be utilized to scan thin sections of resin-embedded tissue mounted on a conductive support. Here we sought to achieve automated imaging without the typical limitations of transmission EM with equivalent or superior quality. Extended areas of tissue were either imaged in two (nanotomy) or in three dimensions (volume EM) by serial-section-based array tomography. Single-beam and fast-recording multi-beam field emission scanning EM instruments were compared using perfusion-fixed rodent kidneys. High-resolution scans produced excellent images of tissue, cells, and organelles down to macromolecular complexes. Digital stitching of image tiles in both modes allowed seamless Google Earth-like zooming from overview to regions of interest at the nanoscale. Large datasets were created that can be rapidly shared between scientists of different disciplines or pathologists using open source software. Three-dimensional array tomography of thin sections was followed by segmentation to visualize selected features in a large volume. Furthermore, correlative light-EM enabled the identification of functional information in a structural context. Thus, limitations in biomedical transmission EM can be overcome by introducing field emission scanning EM-based technology that permits high-quality, large field-of-view nanotomy, volume EM, and correlative light-EM modes. Advantages of virtual microscopy in clinical and experimental nephrology are illustrated.
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Affiliation(s)
- Carsten Dittmayer
- Department of Anatomy, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Irene Wacker
- Centre for Advanced Materials, University of Heidelberg, Heidelberg, Germany
| | - Rasmus R Schröder
- Centre for Advanced Materials, University of Heidelberg, Heidelberg, Germany; BioQuant, University Hospital Heidelberg, Heidelberg, Germany
| | - Sebastian Bachmann
- Department of Anatomy, Charité - Universitätsmedizin Berlin, Berlin, Germany.
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42
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Kugelmann D, Rötzer V, Walter E, Egu DT, Fuchs MT, Vielmuth F, Vargas-Robles H, Schnoor M, Hertl M, Eming R, Rottner K, Schmidt A, Spindler V, Waschke J. Role of Src and Cortactin in Pemphigus Skin Blistering. Front Immunol 2019; 10:626. [PMID: 31024527 PMCID: PMC6461052 DOI: 10.3389/fimmu.2019.00626] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 03/08/2019] [Indexed: 02/06/2023] Open
Abstract
Autoantibodies against desmoglein (Dsg) 1 and Dsg3 primarily cause blister formation in the autoimmune disease pemphigus vulgaris (PV). Src was proposed to contribute to loss of keratinocyte cohesion. However, the role and underlying mechanisms are unclear and were studied here. In keratinocytes, cell cohesion in response to autoantibodies was reduced in Src-dependent manner by two patient-derived PV-IgG fractions as well as by AK23 but not by a third PV-IgG fraction, although Src was activated by all autoantibodies. Loss of cell cohesion was progredient in a timeframe of 24 h and AK23, similar to PV-IgG, interfered with reconstitution of cell cohesion after Ca2+-switch, indicating that the autoantibodies also interfered with desmosome assembly. Dsg3 co-localized along cell contacts and interacted with the Src substrate cortactin. In keratinocytes isolated from cortactin-deficient mice, cell adhesion was impaired and Src-mediated inhibition of AK23-induced loss of cell cohesion for 24 h was significantly reduced compared to wild-type (wt) cells. Similarly, AK23 impaired reconstitution of cell adhesion was Src-dependent only in the presence of cortactin. Likewise, Src inhibition significantly reduced AK23-induced skin blistering in wt but not cortactin-deficient mice. These data suggest that the Src-mediated long-term effects of AK23 on loss of cell cohesion and skin blistering are dependent on cortactin-mediated desmosome assembly. However, in human epidermis PV-IgG-induced skin blistering and ultrastructural alterations of desmosomes were not affected by Src inhibition, indicating that Src may not be critical for skin blistering in intact human skin, at least when high levels of autoantibodies targeting Dsg1 are present.
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Affiliation(s)
- Daniela Kugelmann
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Vera Rötzer
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Elias Walter
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Desalegn Tadesse Egu
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Michael Tobias Fuchs
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Franziska Vielmuth
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany
| | | | - Michael Schnoor
- Department of Molecular Biomedicine, Cinvestav-IPN, Mexico City, Mexico
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Rüdiger Eming
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Klemens Rottner
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany.,Department of Cell Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Ansgar Schmidt
- Instiute of Pathology, Philipps-Universität Marburg, Marburg, Germany
| | - Volker Spindler
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Medical Faculty, Ludwig-Maximilians-Universität München, Munich, Germany
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43
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Waschke J. Desmogleins as signaling hubs regulating cell cohesion and tissue/organ function in skin and heart - EFEM lecture 2018. Ann Anat 2018; 226:96-100. [PMID: 30529571 DOI: 10.1016/j.aanat.2018.11.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 11/27/2018] [Indexed: 01/18/2023]
Abstract
Cell-cell contacts are crucial for intercellular cohesion and formation of endothelial and epithelial barriers. Desmosomes are the adhesive contacts providing mechanical strength to epithelial intercellular adhesion and therefore are most abundant in tissues subjected to high mechanical stress such as the epidermis and heart muscle. Desmogleins (Dsg) besides intercellular adhesion serve as signalling hubs regulating cell behaviour. In desmosomal diseases such as the autoimmune blistering skin disease pemphigus or arrhythmic cardiomyopathy (AC), which is caused by mutations of desmosomal components of cardiomyocyte intercalated discs, the adhesive and signalling functions of desmosomes are impaired. Therefore, our goal is to elucidate the mechanisms regulating adhesion of desmosomes in order to develop new strategies to treat desmosomal diseases. For pemphigus, we have provided evidence that intracellular signalling is required for loss of keratinocyte cohesion and have characterized a first disease-relevant adhesion receptor consisting of Dsg3 and p38MAPK. We propose that signalling patterns correlate with autoantibody profiles and thereby define the clinical phenotypes of pemphigus. Besides direct modulation of signalling pathways we have demonstrated that peptide-mediated crosslinking of Dsg molecules can abolish skin blistering in vivo. A similar approach may be effective to stabilize adhesion in cardiomyocytes of AC hearts. Since we observed that the adrenergic β1-receptor is localized at intercalated discs we evaluate signalling pathways regulating cardiomyocyte cohesion. With adrenergic signalling we have reported a first mechanism to stabilize desmosomal adhesion in intercalated discs and proposed a new function of the sympathicus in the heart we refer to as positive adhesiotropy.
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Affiliation(s)
- Jens Waschke
- Institute of Anatomy, Faculty of Medicine, LMU Munich, Pettenkoferstr. 11, 80336 Munich, Germany.
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Bumiller-Bini V, Cipolla GA, de Almeida RC, Petzl-Erler ML, Augusto DG, Boldt ABW. Sparking Fire Under the Skin? Answers From the Association of Complement Genes With Pemphigus Foliaceus. Front Immunol 2018; 9:695. [PMID: 29686679 PMCID: PMC5900433 DOI: 10.3389/fimmu.2018.00695] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 03/21/2018] [Indexed: 11/13/2022] Open
Abstract
Skin blisters of pemphigus foliaceus (PF) present concomitant deposition of autoantibodies and components of the complement system (CS), whose gene polymorphisms are associated with susceptibility to different autoimmune diseases. To investigate these in PF, we evaluated 992 single-nucleotide polymorphisms (SNPs) of 44 CS genes, genotyped through microarray hybridization in 229 PF patients and 194 controls. After excluding SNPs with minor allele frequency <1%, out of Hardy-Weinberg equilibrium in controls or in strong linkage disequilibrium (r2 ≥ 0.8), 201 SNPs remained for logistic regression. Polymorphisms of 11 genes were associated with PF. MASP1 encodes a crucial serine protease of the lectin pathway (rs13094773: OR = 0.5, p = 0.0316; rs850309: OR = 0.23, p = 0.03; rs3864098: OR = 1.53, p = 0.0383; rs698104: OR = 1.52, p = 0.0424; rs72549154: OR = 0.55, p = 0.0453). C9 (rs187875: OR = 1.46, p = 0.0189; rs700218: OR = 0.12, p = 0.0471) and C8A (rs11206934: OR = 4.02, p = 0.0323) encode proteins of the membrane attack complex (MAC) and C5AR1 (rs10404456: OR = 1.43, p = 0.0155), a potent anaphylatoxin-receptor. Two encode complement regulators: MAC-blocking CD59 (rs1047581: OR = 0.62, p = 0.0152) and alternative pathway-blocking CFH (rs34388368: OR = 2.57, p = 0.0195). One encodes opsonin: C3 (rs4807895: OR = 2.52, p = 0.0239), whereas four encode receptors for C3 fragments: CR1 (haplotype with rs6656401: OR = 1.37, p = 0.0382), CR2 (rs2182911: OR = 0.23, p = 0.0263), ITGAM (CR3, rs12928810: OR = 0.66, p = 0.0435), and ITGAX (CR4, rs11574637: OR = 0.63, p = 0.0056). Associations reinforced former findings, regarding differential gene expression, serum levels, C3, and MAC deposition on lesions. Deregulation of previously barely noticed processes, e.g., the lectin and alternative pathways and opsonization-mediated phagocytosis, also modulate PF susceptibility. The results open new crucial avenues for understanding disease etiology and may improve PF treatment through additional therapeutic targets.
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Affiliation(s)
- Valéria Bumiller-Bini
- Laboratory of Human Molecular Genetics, Department of Genetics, Universidade Federal do Paraná, Curitiba, Brazil
| | - Gabriel Adelman Cipolla
- Laboratory of Human Molecular Genetics, Department of Genetics, Universidade Federal do Paraná, Curitiba, Brazil
| | - Rodrigo Coutinho de Almeida
- Laboratory of Human Molecular Genetics, Department of Genetics, Universidade Federal do Paraná, Curitiba, Brazil
| | - Maria Luiza Petzl-Erler
- Laboratory of Human Molecular Genetics, Department of Genetics, Universidade Federal do Paraná, Curitiba, Brazil
| | - Danillo Gardenal Augusto
- Laboratory of Human Molecular Genetics, Department of Genetics, Universidade Federal do Paraná, Curitiba, Brazil
- Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Ilhéus, Brazil
| | - Angelica Beate Winter Boldt
- Laboratory of Human Molecular Genetics, Department of Genetics, Universidade Federal do Paraná, Curitiba, Brazil
- Laboratory of Molecular Immunopathology, Department of Clinical Pathology, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, Brazil
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Vielmuth F, Walter E, Fuchs M, Radeva MY, Buechau F, Magin TM, Spindler V, Waschke J. Keratins Regulate p38MAPK-Dependent Desmoglein Binding Properties in Pemphigus. Front Immunol 2018; 9:528. [PMID: 29616033 PMCID: PMC5868517 DOI: 10.3389/fimmu.2018.00528] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 02/28/2018] [Indexed: 12/20/2022] Open
Abstract
Keratins are crucial for the anchorage of desmosomes. Severe alterations of keratin organization and detachment of filaments from the desmosomal plaque occur in the autoimmune dermatoses pemphigus vulgaris and pemphigus foliaceus (PF), which are mainly caused by autoantibodies against desmoglein (Dsg) 1 and 3. Keratin alterations are a structural hallmark in pemphigus pathogenesis and correlate with loss of intercellular adhesion. However, the significance for autoantibody-induced loss of intercellular adhesion is largely unknown. In wild-type (wt) murine keratinocytes, pemphigus autoantibodies induced keratin filament retraction. Under the same conditions, we used murine keratinocytes lacking all keratin filaments (KtyII k.o.) as a model system to dissect the role of keratins in pemphigus. KtyII k.o. cells show compromised intercellular adhesion without antibody (Ab) treatment, which was not impaired further by pathogenic pemphigus autoantibodies. Nevertheless, direct activation of p38MAPK via anisomycin further decreased intercellular adhesion indicating that cell cohesion was not completely abrogated in the absence of keratins. Direct inhibition of Dsg3, but not of Dsg1, interaction via pathogenic autoantibodies as revealed by atomic force microscopy was detectable in both cell lines demonstrating that keratins are not required for this phenomenon. However, PF-IgG shifted Dsg1-binding events from cell borders toward the free cell surface in wt cells. This led to a distribution pattern of Dsg1-binding events similar to KtyII k.o. cells under resting conditions. In keratin-deficient keratinocytes, PF-IgG impaired Dsg1-binding strength, which was not different from wt cells under resting conditions. In addition, pathogenic autoantibodies were capable of activating p38MAPK in both KtyII wt and k.o. cells, the latter of which already displayed robust p38MAPK activation under resting conditions. Since inhibition of p38MAPK blocked autoantibody-induced loss of intercellular adhesion in wt cells and restored baseline cell cohesion in keratin-deficient cells, we conclude that p38MAPK signaling is (i) critical for regulation of cell adhesion, (ii) regulated by keratins, and (iii) targets both keratin-dependent and -independent mechanisms.
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Affiliation(s)
- Franziska Vielmuth
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Elias Walter
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Michael Fuchs
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Mariya Y Radeva
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Fanny Buechau
- Division of Cell and Developmental Biology, Institute of Biology, Sächsische Inkubator für Klinische Translation (SIKT), University of Leipzig, Leipzig, Germany
| | - Thomas M Magin
- Division of Cell and Developmental Biology, Institute of Biology, Sächsische Inkubator für Klinische Translation (SIKT), University of Leipzig, Leipzig, Germany
| | - Volker Spindler
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Jens Waschke
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität München, Munich, Germany
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Grudniewska M, Mouton S, Grelling M, Wolters AHG, Kuipers J, Giepmans BNG, Berezikov E. A novel flatworm-specific gene implicated in reproduction in Macrostomum lignano. Sci Rep 2018; 8:3192. [PMID: 29453392 PMCID: PMC5816591 DOI: 10.1038/s41598-018-21107-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 01/30/2018] [Indexed: 12/20/2022] Open
Abstract
Free-living flatworms, such as the planarian Schmidtea mediterranea, are extensively used as model organisms to study stem cells and regeneration. The majority of flatworm studies so far focused on broadly conserved genes. However, investigating what makes these animals different is equally informative for understanding its biology and might have biomedical value. We re-analyzed the neoblast and germline transcriptional signatures of the flatworm M. lignano using an improved transcriptome assembly and show that germline-enriched genes have a high fraction of flatworm-specific genes. We further identified the Mlig-sperm1 gene as a member of a novel gene family conserved only in free-living flatworms and essential for producing healthy spermatozoa. In addition, we established a whole-animal electron microscopy atlas (nanotomy) to visualize the ultrastructure of the testes in wild type worms, but also as a reference platform for different ultrastructural studies in M. lignano. This work demonstrates that investigation of flatworm-specific genes is crucial for understanding flatworm biology and establishes a basis for such future research in M. lignano.
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Affiliation(s)
- Magda Grudniewska
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Stijn Mouton
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Margriet Grelling
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Anouk H G Wolters
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Jeroen Kuipers
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Ben N G Giepmans
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands
| | - Eugene Berezikov
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713AV, Groningen, The Netherlands.
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Spindler V, Waschke J. Pemphigus-A Disease of Desmosome Dysfunction Caused by Multiple Mechanisms. Front Immunol 2018; 9:136. [PMID: 29449846 PMCID: PMC5799217 DOI: 10.3389/fimmu.2018.00136] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 01/16/2018] [Indexed: 02/01/2023] Open
Abstract
Pemphigus is a severe autoimmune-blistering disease of the skin and mucous membranes caused by autoantibodies reducing desmosomal adhesion between epithelial cells. Autoantibodies against the desmosomal cadherins desmogleins (Dsgs) 1 and 3 as well as desmocollin 3 were shown to be pathogenic, whereas the role of other antibodies is unclear. Dsg3 interactions can be directly reduced by specific autoantibodies. Autoantibodies also alter the activity of signaling pathways, some of which regulate cell cohesion under baseline conditions and alter the turnover of desmosomal components. These pathways include Ca2+, p38MAPK, PKC, Src, EGFR/Erk, and several others. In this review, we delineate the mechanisms relevant for pemphigus pathogenesis based on the histology and the ultrastructure of patients’ lesions. We then dissect the mechanisms which can explain the ultrastructural hallmarks detectable in pemphigus patient skin. Finally, we reevaluate the concept that the spectrum of mechanisms, which induce desmosome dysfunction upon binding of pemphigus autoantibodies, finally defines the clinical phenotype.
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Affiliation(s)
- Volker Spindler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Jens Waschke
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
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Abstract
Probes are essential to visualize proteins in their cellular environment, both using light microscopy as well as electron microscopy (EM). Correlated light microscopy and electron microscopy (CLEM) requires probes that can be imaged simultaneously by both optical and electron-dense signals. Existing combinatorial probes often have impaired efficiency, need ectopic expression as a fusion protein, or do not target endogenous proteins. Here, we present FLIPPER-bodies to label endogenous proteins for CLEM. Fluorescent Indicator and Peroxidase for Precipitation with EM Resolution (FLIPPER), the combination of a fluorescent protein and a peroxidase, is fused to a nanobody against a target of interest. The modular nature of these probes allows an easy exchange of components to change its target or color. A general FLIPPER-body targeting GFP highlights histone2B-GFP both in fluorescence and in EM. Similarly, endogenous EGF receptors and HER2 are visualized at nm-scale resolution in ultrastructural context. The small and flexible FLIPPER-body outperforms IgG-based immuno-labeling, likely by better reaching the epitopes. Given the modular domains and possibilities of nanobody generation for other targets, FLIPPER-bodies have high potential to become a universal tool to identify proteins in immuno-CLEM with increased sensitivity compared to current approaches.
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Egu DT, Walter E, Spindler V, Waschke J. Inhibition of p38MAPK signalling prevents epidermal blistering and alterations of desmosome structure induced by pemphigus autoantibodies in human epidermis. Br J Dermatol 2017; 177:1612-1618. [PMID: 28600798 DOI: 10.1111/bjd.15721] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2017] [Indexed: 01/01/2023]
Abstract
BACKGROUND Pemphigus vulgaris (PV) is a skin blistering disease caused by autoantibodies targeting the desmosomal adhesion proteins desmoglein (Dsg) 3 and 1. The mechanisms underlying pemphigus skin blistering are not fully elucidated but p38 mitogen-activated protein kinase (p38MAPK) activation is one of the signalling events necessary for full loss of cell cohesion. However, it is unclear whether ultrastructural hallmarks of desmosome morphology as observed in patients' lesions are mediated by p38MAPK signalling. OBJECTIVES In this study, we tested the relevance of p38MAPK for blister formation and the ultrastructural changes induced by PV autoantibodies in human skin. METHODS Human skin samples were injected with IgG fractions of one patient suffering from mucocutaneous PV (mcPV-IgG), one from mucosal-dominant PV (mdPV-IgG) or AK23, a pathogenic monoclonal Dsg3 antibody derived from a pemphigus mouse model. Samples were processed for histological and electron microscopy analyses. RESULTS mcPV-IgG and AK23 but not mdPV-IgG reduced desmosome size, caused interdesmosomal widening and formation of split desmosomes, and altered keratin filament insertion. In contrast, full epidermal blister formation and lower desmosome number were evident in tissue samples exposed to mcPV-IgG only. Pharmacological inhibition of p38MAPK blunted the reduction of desmosome number and size, ameliorated interdesmosomal widening and loss of keratin insertion and prevented mcPV-IgG-induced blister formation. CONCLUSIONS Our data demonstrate that blistering can be prevented by inhibition of p38MAPK in the human epidermis. Moreover, typical morphological alterations induced by mcPV-IgG such as interdesmosomal widening and the reduction of desmosome size at least in part require p38MAPK signalling.
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Affiliation(s)
- D T Egu
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität (LMU), München, D-80336, Germany
| | - E Walter
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität (LMU), München, D-80336, Germany
| | - V Spindler
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität (LMU), München, D-80336, Germany
| | - J Waschke
- Department I, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität (LMU), München, D-80336, Germany
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Abstract
Pemphigus is a severe autoimmune blistering disease mediated by pathogenic anti-desmoglein antibodies leading to an inter keratinocyte disjunction. Rituximab is a monoclonal antibody that binds to the CD-20 antigen of B lymphocytes, which causes B-cell depletion and a subsequent reduction in pathogenic autoantibodies. Its therapeutic role in pemphigus has been progressively growing with increasing evidence of successful outcomes. Rituximab was initially off-labeled used as an alternative in patients with recalcitrant or relapsing pemphigus and in patients with contraindications to systemic corticosteroids. Recently, a large randomized clinical trial has shown that first-line use of rituximab combined with short-term prednisone regimen was both more effective and potentially safer than a standard regimen of high doses of corticosteroids in patients with moderate to severe pemphigus.
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Affiliation(s)
- Vivien Hebert
- Department of Dermatology, Rouen University Hospital, & INSERM U 1234, Centre de référence des maladies bulleuses autoimmunes, Normandie University, Rouen, France
| | - Pascal Joly
- Department of Dermatology, Rouen University Hospital, & INSERM U 1234, Centre de référence des maladies bulleuses autoimmunes, Normandie University, Rouen, France
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