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Erb T, Mihai S, Strauß R, Herbst L, Castellanos I, Diesch K, Cipa F, Bihlmaier K, Lang AK, Ganslmayer M, Willam C, Bremer F, Fürst J, Beyer C, Bogdan C, Rath A, Held J. β-(1→3)-D-glucan- and mannan-guided early termination of antifungal therapy in ICU patients: a randomized controlled study. Antimicrob Agents Chemother 2023; 67:e0072523. [PMID: 37823695 PMCID: PMC10648872 DOI: 10.1128/aac.00725-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 08/20/2023] [Indexed: 10/13/2023] Open
Abstract
Candida spp. are frequently encountered in specimens from ICUs. However, most of these detections represent colonization. Nevertheless, clinical practice shows that a considerable proportion of these patients will receive antifungal therapy (AT). β-(1→3)-D-glucan (BDG) and mannan are fungal biomarkers with high negative predictive values. We aimed to examine whether biomarker-guided discontinuation of AT can reduce the antifungal consumption. Therefore, we conducted a prospective, randomized intervention study between 1 April 2019 and 31 March 2020. All adult ICU patients with a newly started systemic AT but without fungal infection were eligible for inclusion. Enrolled patients were randomized into an intervention and a control group. In both groups, serum BDG and mannan were determined on days 1 and 2 of AT. If all measurements were negative, AT was discontinued in the intervention group. The primary endpoint was antifungal use. The study was terminated after 12 months. Until this time-point, 41 patients had been included. In the intervention group (n = 19), AT was stopped in only two patients because all others showed either positive BDG and/or mannan levels. One of these two patients developed candidemia and AT had to be restarted. There was no significant difference in the primary and secondary endpoints. In summary, the strategy of using two negative BDG and mannan levels to stop AT failed to reduce antifungal consumption in our cohort. Indeed, there will inevitably be patients with invasive candidiasis in whom necessary AT is discontinued. The optimal patient population, biomarker set, and termination criteria are critical to the success of biomarker-based termination strategies.
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Affiliation(s)
- Timothy Erb
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene; Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Sidonia Mihai
- Zentrallabor, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Richard Strauß
- Medizinische Klinik 1, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Larissa Herbst
- Medizinische Klinik 4, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Ixchel Castellanos
- Anästhesiologische Klinik, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Katharina Diesch
- Medizinisches Zentrum für Informations- und Kommunikationstechnik, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Franziska Cipa
- Zentrallabor, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Karl Bihlmaier
- Medizinische Klinik 4, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Anne-Katharina Lang
- Anästhesiologische Klinik, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Marion Ganslmayer
- Medizinische Klinik 1, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Carsten Willam
- Medizinische Klinik 4, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Frank Bremer
- Anästhesiologische Klinik, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Julia Fürst
- Medizinische Klinik 1, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Christian Beyer
- Medizinische Klinik 1, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Christian Bogdan
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene; Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Anca Rath
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene; Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Jürgen Held
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene; Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany
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2
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Valor-Méndez L, Fürst J, Strauß R, Wacker J, Schett G, Manger B, Kleyer A. Voriconazole-induced synovitis, enthesitis and periostitis. Arthritis Rheumatol 2022; 74:1183. [PMID: 35137565 DOI: 10.1002/art.42085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/12/2022] [Accepted: 01/22/2022] [Indexed: 11/07/2022]
Affiliation(s)
- Larissa Valor-Méndez
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich Alexander University Erlangen- Nuremberg and Universitätsklinikum Erlangen. Erlangen, Germany.,Deutsches Zentrum für Immuntherapie (DZI) FAU Erlangen- Nürnberg and Universitätsklinikum Erlangen. Erlangen, Germany
| | - Julia Fürst
- Department of Internal Medicine 1, Friedrich Alexander University Erlangen- Nuremberg and Universitätsklinikum Erlangen. Erlangen, Germany
| | - Richard Strauß
- Department of Internal Medicine 1, Friedrich Alexander University Erlangen- Nuremberg and Universitätsklinikum Erlangen. Erlangen, Germany
| | - Jochen Wacker
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich Alexander University Erlangen- Nuremberg and Universitätsklinikum Erlangen. Erlangen, Germany.,Deutsches Zentrum für Immuntherapie (DZI) FAU Erlangen- Nürnberg and Universitätsklinikum Erlangen. Erlangen, Germany
| | - Georg Schett
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich Alexander University Erlangen- Nuremberg and Universitätsklinikum Erlangen. Erlangen, Germany.,Deutsches Zentrum für Immuntherapie (DZI) FAU Erlangen- Nürnberg and Universitätsklinikum Erlangen. Erlangen, Germany
| | - Bernhard Manger
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich Alexander University Erlangen- Nuremberg and Universitätsklinikum Erlangen. Erlangen, Germany.,Deutsches Zentrum für Immuntherapie (DZI) FAU Erlangen- Nürnberg and Universitätsklinikum Erlangen. Erlangen, Germany
| | - Arnd Kleyer
- Department of Internal Medicine 3, Rheumatology and Immunology, Friedrich Alexander University Erlangen- Nuremberg and Universitätsklinikum Erlangen. Erlangen, Germany.,Deutsches Zentrum für Immuntherapie (DZI) FAU Erlangen- Nürnberg and Universitätsklinikum Erlangen. Erlangen, Germany
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3
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Kubánková M, Hohberger B, Hoffmanns J, Fürst J, Herrmann M, Guck J, Kräter M. Physical phenotype of blood cells is altered in COVID-19. Biophys J 2021; 120:2838-2847. [PMID: 34087216 PMCID: PMC8169220 DOI: 10.1016/j.bpj.2021.05.025] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 05/07/2021] [Accepted: 05/27/2021] [Indexed: 12/15/2022] Open
Abstract
Clinical syndrome coronavirus disease 2019 (COVID-19) induced by severe acute respiratory syndrome coronavirus 2 is characterized by rapid spreading and high mortality worldwide. Although the pathology is not yet fully understood, hyperinflammatory response and coagulation disorders leading to congestions of microvessels are considered to be key drivers of the still-increasing death toll. Until now, physical changes of blood cells have not been considered to play a role in COVID-19 related vascular occlusion and organ damage. Here, we report an evaluation of multiple physical parameters including the mechanical features of five frequent blood cell types, namely erythrocytes, lymphocytes, monocytes, neutrophils, and eosinophils. More than four million blood cells of 17 COVID-19 patients at different levels of severity, 24 volunteers free from infectious or inflammatory diseases, and 14 recovered COVID-19 patients were analyzed. We found significant changes in lymphocyte stiffness, monocyte size, neutrophil size and deformability, and heterogeneity of erythrocyte deformation and size. Although some of these changes recovered to normal values after hospitalization, others persisted for months after hospital discharge, evidencing the long-term imprint of COVID-19 on the body.
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Affiliation(s)
- Markéta Kubánková
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Bettina Hohberger
- Department of Ophthalmology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Jakob Hoffmanns
- Department of Ophthalmology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Julia Fürst
- Department of Internal Medicine 1, University Medical Center Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Martin Herrmann
- Department of Internal Medicine 3, University Medical Center Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany; Deutsches Zentrum Immuntherapie, Erlangen, Germany
| | - Jochen Guck
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany; Department of Physics, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.
| | - Martin Kräter
- Max Planck Institute for the Science of Light & Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
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Hohberger B, Ganslmayer M, Lucio M, Kruse F, Hoffmanns J, Moritz M, Rogge L, Heltmann F, Szewczykowski C, Fürst J, Raftis M, Bergua A, Zenkel M, Gießl A, Schlötzer-Schrehardt U, Lehmann P, Strauß R, Mardin C, Herrmann M. Retinal Microcirculation as a Correlate of a Systemic Capillary Impairment After Severe Acute Respiratory Syndrome Coronavirus 2 Infection. Front Med (Lausanne) 2021; 8:676554. [PMID: 34307408 PMCID: PMC8299003 DOI: 10.3389/fmed.2021.676554] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 06/08/2021] [Indexed: 12/14/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), affects the pulmonary systems via angiotensin-converting enzyme-2 (ACE-2) receptor, being an entry to systemic infection. As COVID-19 disease features ACE-2 deficiency, a link to microcirculation is proposed. Optical coherence tomography angiography (OCT-A) enables non-invasive analysis of retinal microvasculature. Thus, an impaired systemic microcirculation might be mapped on retinal capillary system. As recent OCT-A studies, analyzing microcirculation in two subdivided layers, yielded contrary results, an increased subdivision of retinal microvasculature might offer an even more fine analysis. The aim of the study was to investigate retinal microcirculation by OCT-A after COVID-19 infection in three subdivided layers (I). In addition, short-term retinal affections were monitored during COVID-19 disease (II). Considering (I), a prospective study (33 patientspost-COVID and 28 controls) was done. Macula and peripapillary vessel density (VD) were scanned with the Spectralis II. Macula VD was measured in three layers: superficial vascular plexus (SVP), intermediate capillary plexus (ICP), and deep capillary plexus (DCP). Analysis was done by the EA-Tool, including an Anatomical Positioning System and an analysis of peripapillary VD by implementing Bruch's membrane opening (BMO) landmarks. Overall, circular (c1, c2, and c3) and sectorial VD (s1-s12) was analyzed. Considering (II), in a retrospective study, 29 patients with severe complications of COVID-19 infection, hospitalized at the intensive care unit, were monitored for retinal findings at bedside during hospitalization. (I) Overall (p = 0.0133) and circular (c1, p = 0.00257; c2, p = 0.0067; and c3, p = 0.0345). VD of the ICP was significantly reduced between patientspost-COVID and controls, respectively. Overall (p = 0.0179) and circular (c1, p = 0.0189) peripapillary VD was significantly reduced between both groups. Subgroup analysis of hospitalized vs. non-hospitalized patientspost-COVID yielded a significantly reduced VD of adjacent layers (DCP and SVP) with increased severity of COVID-19 disease. Clinical severity parameters showed a negative correlation with VD (ICP) and peripapillary VD. (II) Funduscopy yielded retinal hemorrhages and cotton wool spots in 17% of patients during SARS-CoV-2 infection. As VD of the ICP and peripapillary regions was significantly reduced after COVID-19 disease and showed a link to clinical severity markers, we assume that the severity of capillary impairment after COVID-19 infection is mapped on retinal microcirculation, visualized by non-invasive OCT-A.
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Affiliation(s)
- Bettina Hohberger
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Marion Ganslmayer
- Department of Internal Medicine 1, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Marianna Lucio
- Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, Germany
| | - Friedrich Kruse
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Jakob Hoffmanns
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Moritz
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Lennart Rogge
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Felix Heltmann
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Charlotte Szewczykowski
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Julia Fürst
- Department of Internal Medicine 1, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Maximilian Raftis
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Antonio Bergua
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Matthias Zenkel
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Andreas Gießl
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Ursula Schlötzer-Schrehardt
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Paul Lehmann
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Richard Strauß
- Department of Internal Medicine 1, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Christian Mardin
- Department of Ophthalmology, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | - Martin Herrmann
- Department of Internal Medicine 3, University of Erlangen-Nürnberg, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
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Wallukat G, Hohberger B, Wenzel K, Fürst J, Schulze-Rothe S, Wallukat A, Hönicke AS, Müller J. Functional autoantibodies against G-protein coupled receptors in patients with persistent Long-COVID-19 symptoms. J Transl Autoimmun 2021; 4:100100. [PMID: 33880442 PMCID: PMC8049853 DOI: 10.1016/j.jtauto.2021.100100] [Citation(s) in RCA: 149] [Impact Index Per Article: 49.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 04/02/2021] [Accepted: 04/10/2021] [Indexed: 02/06/2023] Open
Abstract
Impairment of health after overcoming the acute phase of COVID-19 is being observed more and more frequently. Here different symptoms of neurological and/or cardiological origin have been reported. With symptoms, which are very similar to the ones reported but are not caused by SARS-CoV-2, the occurrence of functionally active autoantibodies (fAABs) targeting G-protein coupled receptors (GPCR-fAABs) has been discussed to be involved. We, therefore investigated, whether GPCR-fAABs are detectable in 31 patients suffering from different Long-COVID-19 symptoms after recovery from the acute phase of the disease. The spectrum of symptoms was mostly of neurological origin (29/31 patients), including post-COVID-19 fatigue, alopecia, attention deficit, tremor and others. Combined neurological and cardiovascular disorders were reported in 17 of the 31 patients. Two recovered COVID-19 patients were free of follow-up symptoms. All 31 former COVID-19 patients had between 2 and 7 different GPCR-fAABs that acted as receptor agonists. Some of those GPCR-fAABs activate their target receptors which cause a positive chronotropic effect in neonatal rat cardiomyocytes, the read-out in the test system for their detection (bioassay for GPCR-fAAB detection). Other GPCR-fAABs, in opposite, cause a negative chronotropic effect on those cells. The positive chronotropic GPCR-fAABs identified in the blood of Long-COVID patients targeted the β2-adrenoceptor (β2-fAAB), the α1-adrenoceptor (α1-fAAB), the angiotensin II AT1-receptor (AT1-fAAB), and the nociceptin-like opioid receptor (NOC-fAAB). The negative chronotropic GPCR-fAABs identified targeted the muscarinic M2-receptor (M2-fAAB), the MAS-receptor (MAS-fAAB), and the ETA-receptor (ETA-fAAB). It was analysed which of the extracellular receptor loops was targeted by the autoantibodies.
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Key Words
- ACE2, Angiotensin-converting enzyme 2 receptors
- AT1-fAAB, Autoantibody targeting the angiotensin II AT1 receptor
- Autoantibody
- Autoimmunity
- COVID-19
- CRPS, Complex regional pain syndrome
- ETA-fAAB, Autoantibody targeting the endothelin receptor
- Fatigue
- GPCR, G-protein coupled receptors
- Long-COVID
- M2-fAAB, Autoantibody targeting the muscarinic receptor
- MAS-fAAB, Autoantibody targeting the MAS receptor
- NOC-fAAB, Functionally active autoantibody against the nociceptin receptor
- PoTS, Postural orthostatic tachycardia syndrome
- Post-covid-19 symptom
- RAS, Renin angiotensin system
- SARS, Severe acute respiratory syndrome
- fAAB, Functional autoantibody
- α1-fAAB, Autoantibody targeting the alpha1-adrenoceptor
- β2-fAAB, Autoantibody targeting the beta2-adrenoceptor
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Affiliation(s)
- Gerd Wallukat
- Experimental and Clinical Research Center, Charité Campus Buch, Max-Delbrück Center for Molecular Medicine, Berlin, Germany
- Berlin Cures GmbH, Berlin; Germany
| | - Bettina Hohberger
- Department of Ophthalmology, University of Erlangen, Friedrich-Alexander-University of Erlangen-Nürnberg, Erlangen, Germany
| | | | - Julia Fürst
- Department of Medicine 1, University Hospital Erlangen, Erlangen, Germany
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6
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Staats LAN, Pfeiffer H, Knopf J, Lindemann A, Fürst J, Kremer AE, Hackstein H, Neurath MF, Muñoz LE, Achenbach S, Leppkes M, Herrmann M, Schett G, Steffen U. IgA2 Antibodies against SARS-CoV-2 Correlate with NET Formation and Fatal Outcome in Severely Diseased COVID-19 Patients. Cells 2020; 9:E2676. [PMID: 33322797 PMCID: PMC7764693 DOI: 10.3390/cells9122676] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/01/2020] [Accepted: 12/09/2020] [Indexed: 02/06/2023] Open
Abstract
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) leads to an adaptive immune response in the host and the formation of anti-SARS-CoV-2 specific antibodies. While IgG responses against SARS-CoV-2 have been characterized quite well, less is known about IgA. IgA2 activates immune cells and induces inflammation and neutrophil extracellular trap (NET) formation which may contribute to organ injury and fatal outcome in SARS-CoV-2-infected patients. SARS-CoV-2 spike protein specific antibody levels were measured in plasma samples of 15 noninfected controls and 82 SARS-CoV-2-infected patients with no or mild symptoms, moderate symptoms (hospitalization) or severe disease (intensive care unit, ICU). Antibody levels were compared to levels of C-reactive protein (CRP) and circulating extracellular DNA (ecDNA) as markers for general inflammation and NET formation, respectively. While levels of SARS-CoV-2-specific IgG were similar in all patient groups, IgA2 antibodies were restricted to severe disease and showed the strongest discrimination between nonfatal and fatal outcome in patients with severe SARS-CoV-2 infection. While anti-SARS-CoV-2 IgG and IgA2 levels correlated with CRP levels in severely diseased patients, only anti-SARS-CoV-2 IgA2 correlated with ecDNA. These data suggest that the formation of anti-SARS-CoV-2 IgA2 during SARS-CoV-2 infection is a marker for more severe disease related to NET formation and poor outcome.
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Affiliation(s)
- Léonie A. N. Staats
- Department of Internal Medicine 1, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (L.A.N.S.); (A.L.); (J.F.); (A.E.K.); (M.F.N.); (M.L.)
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
| | - Hella Pfeiffer
- Department of Transfusion Medicine and Haemostaseology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (H.P.); (H.H.); (S.A.)
| | - Jasmin Knopf
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
- Department of Internal Medicine 3, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Aylin Lindemann
- Department of Internal Medicine 1, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (L.A.N.S.); (A.L.); (J.F.); (A.E.K.); (M.F.N.); (M.L.)
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
| | - Julia Fürst
- Department of Internal Medicine 1, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (L.A.N.S.); (A.L.); (J.F.); (A.E.K.); (M.F.N.); (M.L.)
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
| | - Andreas E. Kremer
- Department of Internal Medicine 1, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (L.A.N.S.); (A.L.); (J.F.); (A.E.K.); (M.F.N.); (M.L.)
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
| | - Holger Hackstein
- Department of Transfusion Medicine and Haemostaseology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (H.P.); (H.H.); (S.A.)
| | - Markus F. Neurath
- Department of Internal Medicine 1, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (L.A.N.S.); (A.L.); (J.F.); (A.E.K.); (M.F.N.); (M.L.)
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
| | - Luis E. Muñoz
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
- Department of Internal Medicine 3, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Susanne Achenbach
- Department of Transfusion Medicine and Haemostaseology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (H.P.); (H.H.); (S.A.)
| | - Moritz Leppkes
- Department of Internal Medicine 1, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; (L.A.N.S.); (A.L.); (J.F.); (A.E.K.); (M.F.N.); (M.L.)
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
| | - Martin Herrmann
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
- Department of Internal Medicine 3, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Georg Schett
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
- Department of Internal Medicine 3, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Ulrike Steffen
- Deutsches Zentrum Immuntherapie (DZI), 91054 Erlangen, Germany; (J.K.); (L.E.M.); (M.H.); (G.S.)
- Department of Internal Medicine 3, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
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7
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Brenke C, Fürst J, Katsigiannis S, Carolus AE. High accuracy of external ventricular drainage placement using anatomical landmarks. Neurochirurgie 2020; 66:435-441. [PMID: 33080249 DOI: 10.1016/j.neuchi.2020.09.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 05/16/2020] [Accepted: 09/13/2020] [Indexed: 11/16/2022]
Abstract
BACKGROUND The conventional approach for external ventricular drainage (EVD) application is the freehand method. Technical devices can improve the accuracy of placement, but they have not yet replaced anatomical landmarks owing to the cost and effort that they entail. There is disagreement as to whether freehand EVD application is safe enough to be accepted as a standard technique. Many authors have investigated the final catheter position in retrospect. They describe variable rates of malpositioning. However, few studies have assessed in how far cranial surface anatomy has really been respected during burr-hole drilling and catheter insertion. The aim of this study was to investigate parameters that might play a part in determining the final intracranial catheter position. METHODS In all, 100 pre- and postprocedural thin-layer computed-tomography (CT) scans of EVD patients were analysed with the help of JiveX® and OsiriX Lite® software. A series of anatomical and catheter-related parameters, including inter alia intraventricular blood, midline shift, burr-hole location and catheter entrance angle, were correlated with the final catheter position. RESULTS A majority of EVDs show an optimal or nearly optimal position. Only the deviation of catheter entrance angle has a significant influence on catheter malpositioning. The burr-hole location can vary within an area of several centimetres around the coronary suture. CONCLUSIONS The freehand application of EVD is safe as long as the intracranial anatomy is not disfigured to a large extent, the surface measurements are carried out precisely and the puncturing is done perpendicularly to the skull.
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Affiliation(s)
- C Brenke
- Department of Neurosurgery, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-35, 44892 Bochum, Germany
| | - J Fürst
- Department of Neurosurgery, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-35, 44892 Bochum, Germany
| | - S Katsigiannis
- Department of Neurosurgery, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-35, 44892 Bochum, Germany
| | - A E Carolus
- Department of Neurosurgery, University Hospital Knappschaftskrankenhaus Bochum, In der Schornau 23-35, 44892 Bochum, Germany.
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8
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Kasakowskij T, Fürst J, Fischer J, Fietkiewicz KJ. Network enforcement as denunciation endorsement? A critical study on legal enforcement in social media. Telematics and Informatics 2020. [DOI: 10.1016/j.tele.2019.101317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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9
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Carolus A, Fürst J, Weihe S, Hesse M, Brenke C. Development of a pin-less reference head frame: An experimental setup and preliminary experiences. Interdisciplinary Neurosurgery 2018. [DOI: 10.1016/j.inat.2018.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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10
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Fürst J, Sturman B, Buse K, Breunig I. Whispering gallery resonators with broken axial symmetry: Theory and experiment. Opt Express 2016; 24:20143-20155. [PMID: 27607622 DOI: 10.1364/oe.24.020143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Axial symmetry is the cornerstone for theory and applications of high-Q optical whispering gallery resonators (WGRs). Nevertheless, research on birefringent crystalline material persistently pushes towards breaking this symmetry. We show theoretically and experimentally that the effect of broken axial symmetry, caused by optical anisotropy, is modest for the resonant frequencies and Q-factors of the WGR modes. Thus, the most important equatorial whispering gallery modes can be quantitatively described and experimentally identified. At the same time, the effect of broken axial symmetry on the light field distribution of the whispering gallery modes is typically very strong. This qualitatively modifies the phase-matching for the χ(2) nonlinear processes and enables broad-band second harmonic generation and optical parametric oscillation. The effect of weak geometric ellipticity in nominally symmetric WGRs is also considered. Altogether our findings pave the way for an extensive use of numerous birefringent (uniaxial and biaxial) crystals with broad transparency window and large χ(2) coefficients in nonlinear optics with WGRs.
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Běták V, Sváček P, Novotný J, Fürst J, Fořt J. On Application of EARSM Turbulence Model for Simulation of Flow Field behind Rack Station. EPJ Web of Conferences 2013. [DOI: 10.1051/epjconf/20134501013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Hummelshøj JS, Landis DD, Voss J, Jiang T, Tekin A, Bork N, Dułak M, Mortensen JJ, Adamska L, Andersin J, Baran JD, Barmparis GD, Bell F, Bezanilla AL, Bjork J, Björketun ME, Bleken F, Buchter F, Bürkle M, Burton PD, Buus BB, Calborean A, Calle-Vallejo F, Casolo S, Chandler BD, Chi DH, Czekaj I, Datta S, Datye A, DeLaRiva A, Despoja V, Dobrin S, Engelund M, Ferrighi L, Frondelius P, Fu Q, Fuentes A, Fürst J, García-Fuente A, Gavnholt J, Goeke R, Gudmundsdottir S, Hammond KD, Hansen HA, Hibbitts D, Hobi E, Howalt JG, Hruby SL, Huth A, Isaeva L, Jelic J, Jensen IJT, Kacprzak KA, Kelkkanen A, Kelsey D, Kesanakurthi DS, Kleis J, Klüpfel PJ, Konstantinov I, Korytar R, Koskinen P, Krishna C, Kunkes E, Larsen AH, Lastra JMG, Lin H, Lopez-Acevedo O, Mantega M, Martínez JI, Mesa IN, Mowbray DJ, Mýrdal JSG, Natanzon Y, Nistor A, Olsen T, Park H, Pedroza LS, Petzold V, Plaisance C, Rasmussen JA, Ren H, Rizzi M, Ronco AS, Rostgaard C, Saadi S, Salguero LA, Santos EJG, Schoenhalz AL, Shen J, Smedemand M, Stausholm-Møller OJ, Stibius M, Strange M, Su HB, Temel B, Toftelund A, Tripkovic V, Vanin M, Viswanathan V, Vojvodic A, Wang S, Wellendorff J, Thygesen KS, Rossmeisl J, Bligaard T, Jacobsen KW, Nørskov JK, Vegge T. Density functional theory based screening of ternary alkali-transition metal borohydrides: A computational material design project. J Chem Phys 2009; 131:014101. [DOI: 10.1063/1.3148892] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Fürst J, Bottà G, Saino S, Dopinto S, Gandini R, Dossena S, Vezzoli V, Rodighiero S, Bazzini C, Garavaglia ML, Meyer G, Jakab M, Ritter M, Wappl-Kornherr E, Paulmichl M. The ICln interactome. Acta Physiol (Oxf) 2006; 187:43-9. [PMID: 16734741 DOI: 10.1111/j.1748-1716.2006.01549.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The many different functional phenotypes described in mammalian cells can only be explained by an intense interaction of the underlying proteins, substantiated by the fact that the number of independently expressed proteins in living cells seems not to exceed 25 K, a number way too small to explain the >250 K different phenotypes on a one-protein-one-function base. Therefore, the study of the interactome of the different proteins is of utmost importance. Here, we describe the present knowledge of the ICln interactome. ICln is a protein, we cloned and whose function was reported to be as divers as (i) ion permeation, (ii) cytoskeletal organization, and (iii) RNA processing. The role of ICln in these different functional modules can be described best as being a 'connector hub' with 'date hub' function.
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Affiliation(s)
- J Fürst
- Department of Physiology and Medical Physics, Innsbruck Medical University, Innsbruck, Austria
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15
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Gschwentner M, Fürst J, Ritter M, Bazzini C, Wöll E, Dienstl A, Jakab M, König M, Scandella E, Rudzki J, Botta G, Meyer G, Lang F, Deetjen P, Paulmichl M. Icln, An Ion Channel-Forming Protein Associated with Cell Volume Regulation. Exp Physiol 2004. [DOI: 10.1111/j.1469-445x.1999.01941.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Ritter M, Bertocchi C, Jakab M, Fürst J, Paulmichl M. Further characterization of the nematode IClnN2 protein reconstituted in lipid bilayers. Adv Exp Med Biol 2004; 559:245-251. [PMID: 18727245 DOI: 10.1007/0-387-23752-6_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- M Ritter
- Institute of Physiology, University of Innsbruck, Fritz-Pregl Strasse 3, A-6020 Innsbruck, Austria.
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17
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Fürst J, Gschwentner M, Ritter M, Bottà G, Jakab M, Mayer M, Garavaglia L, Bazzini C, Rodighiero S, Meyer G, Eichmüller S, Wöll E, Paulmichl M. Molecular and functional aspects of anionic channels activated during regulatory volume decrease in mammalian cells. Pflugers Arch 2002; 444:1-25. [PMID: 11976912 DOI: 10.1007/s00424-002-0805-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2002] [Indexed: 10/27/2022]
Abstract
The ability of cells to readjust their volume after swelling, a phenomenon known as regulatory volume decrease (RVD), is a fundamental biological achievement guaranteeing survival and function of cells under osmotic stress. This article reviews the mechanisms of RVD in mammalian cells with special emphasis on the activation of ion channels during RVD.
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Affiliation(s)
- J Fürst
- Institut für Physiologie, Universität Innsbruck, Fritz Pregl-Strasse 3, Austria
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18
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Schmarda A, Fresser F, Gschwentner M, Fürst J, Ritter M, Lang F, Baier G, Paulmichl M. Determination of protein-protein interactions of ICIn by the yeast two-hybrid system. Cell Physiol Biochem 2001; 11:55-60. [PMID: 11275683 DOI: 10.1159/000047792] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
ICln is a ubiquitously expressed eukaryotic protein. Expression of the protein in Xenopus laevis oocytes, the knocking-down of the protein in fibroblasts, or the reconstitution of the protein in lipid bilayer led to the assumption that this protein is an ionic channel or a significant part thereof. However, other possible roles for ICln in potential regulatory mechanisms have been postulated, as diverse as regulator of cell morphology by interacting with the Skb1 protein and/or interaction with core spliceosomal proteins. Here we show that ICln is able to interact with SnRNP core proteins SmD1, SmD2, SmD3, SmX5 and SmB/B'.
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Affiliation(s)
- A Schmarda
- Department of Physiology, Institute for Medical Biology and Human Genetics, University of Innsbruck, Austria
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19
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Fürst J, Jakab M, König M, Ritter M, Gschwentner M, Rudzki J, Danzl J, Mayer M, Burtscher CM, Schirmer J, Maier B, Nairz M, Chwatal S, Paulmichl M. Structure and function of the ion channel ICln. Cell Physiol Biochem 2001; 10:329-34. [PMID: 11125213 DOI: 10.1159/000016374] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Normal function of organs and cells is tightly linked to the cytoarchitecture. Control of the cell volume is therefore vital for the organism. A widely established strategy of cells to counteract swelling is the activation of chloride and potassium channels, which leads to a net efflux of salt followed by water - a process termed regulatory volume decrease. Since there is evidence for swelling-dependent chloride channels (IClswell) being activated also during pathological processes, the identification of the molecular entity underlying IClswell is of utmost importance. Several proteins are discussed as the channel forming IClswell, i.e. phospholemman, p-glycoprotein, CLC-3 and ICln. In this review we would like to focus on the properties of ICln, a protein cloned from a Madin Darby canine kidney (MDCK) cell library whose expression in Xenopus laevis oocytes resulted in a nucleotide sensitive outwardly rectifying chloride current closely resembling the biophysical properties of IClswell.
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Affiliation(s)
- J Fürst
- Department of Physiology, University of Innsbruck, Fritz-Pregl-Str. 3, A-6020 Innsbruck, Austria
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20
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Scandella E, Nagl UO, Oehl B, Bergmann F, Gschwentner M, Fürst J, Schmarda A, Ritter M, Waldegger S, Lang F, Deetjen P, Paulmichl M. The promoter for constitutive expression of the human ICln gene CLNS1A. J Biol Chem 2000; 275:15613-20. [PMID: 10821842 DOI: 10.1074/jbc.275.21.15613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The ICln protein is expressed ubiquitously in mammals. Experiments designed to knock down the ICln protein in NIH 3T3 fibroblasts as well as in epithelial cells led to the conclusion that this protein is crucially involved in volume regulation after cytoplasmic swelling. Reconstitution of the ICln protein in lipid bilayers revealed the ion channel nature of ICln. Here we describe a new human promoter sequence, composed of 89 nucleotides, which is responsible for a highly constitutive expression of the ICln protein. The promoter sequence lacks a TATA box, and the transcription can be effected at multiple sites. In addition to the starting sites, upstream sequence elements are mandatory for an efficient transcription of the ICln gene (CLNS1A). These new nucleotide elements were defined by site-directed mutagenesis.
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Affiliation(s)
- E Scandella
- Department of Physiology, University of Innsbruck, Fritz-Pregl Strasse 3, A-6020 Innsbruck, Austria
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21
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Fürst J, Bazzini C, Jakab M, Meyer G, König M, Gschwentner M, Ritter M, Schmarda A, Bottà G, Benz R, Deetjen P, Paulmichl M. Functional reconstitution of ICln in lipid bilayers. Pflugers Arch 2000; 440:100-15. [PMID: 10864003 DOI: 10.1007/s004240000250] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Reconstitution of purified ICln in lipid bilayer leads to functional ion channels showing varying rectification. The reconstituted single channels have a conductance of approximately equal to 3 pS and their open probability is sensitive to nucleoside analogues. Mutation of a putative nucleotide binding site identified at the predicted extracellular mouth of the ICln channel protein leads to the reduction of the nucleoside-analogue sensitivity. Reconstituted ICln channels can be permeated both by cations and anions. The relative permeability of cations over anions depends on the presence of calcium. In the presence of calcium reconstituted ICln channels are more permeable to bromide than chloride, and more permeable to potassium than sodium. Similarly in NIH3T3 fibroblasts, the relative permeability of cations over anions of swelling-dependent chloride channels depends on extracellular calcium. Site-directed mutagenesis revealed the calcium-binding site responsible for the shift of the selectivity from cations towards anions of reconstituted ICln channels. Additional indirect structural information has been obtained by mutating a histidine in the predicted pore region of ICln. This histidine seems to have access to the ion-conducting tunnel of the pore. Our experiments show that ICln can act as an ionic channel, which does not exclude additional functions of the protein in regulatory mechanisms of the cell. Since knocking down the ICln protein in fibroblasts and epithelial cells leads to an impaired regulatory volume decrease (RVD) after cytoplasmic swelling and reconstituted ICln channels show several biophysical features of ion channels activated after swelling, ICln is a molecular candidate for these channels.
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Affiliation(s)
- J Fürst
- Department of Physiology, University of Innsbruck, Austria
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22
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Gschwentner M, Fürst J, Ritter M, Bazzini C, Wöll E, Dienstl A, Jakab M, König M, Scandella E, Rudzki J, Botta G, Meyer G, Lang F, Deetjen P, Paulmichl M. ICln, an ion channel-forming protein associated with cell volume regulation. Exp Physiol 1999; 84:1023-31. [PMID: 10564699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
It is not resolved whether the anionic channel involved in volume regulation after cell swelling comprises one or more subunits. Moreover, it remains to be determined which of the different proteins cloned so far, for which an involvement in cell volume regulation has been postulated, is the ideal candidate. In this review, we consider the role of the ICln protein, cloned from MDCK cells, in cell volume regulation.
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Affiliation(s)
- M Gschwentner
- Department of Physiology, University of Innsbruck, Fritz-Pregl-Strasse 3, A-6020 Innsbruck, Austria
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23
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Nagl UO, Erdel M, Bergmann F, Oehl B, Scandella E, Musante L, Galietta LJ, Gschwentner M, Fürst J, Schmarda A, Hofer S, Utermann G, Deetjen P, Paulmichl M. Characterization of the human gene coding for the swelling-dependent chloride channel ICln at position 11q13.5-14.1 (CLNS1A) and further characterization of the chromosome 6 (CLNS1B) localization. Gene 1998; 209:59-63. [PMID: 9524223 DOI: 10.1016/s0378-1119(98)00002-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Expression cloning revealed a chloride channel (ICln) that we found to be fundamental for the regulatory volume decrease in a variety of cells. The chromosomal localization of the human ICln-gene showed two loci, one at chromosome 11 in position q13.5-q14.1, termed CLNS1A, and a second one at chromosome 6 at position p12.1-q13, termed CLNS1B. In this study, we offer a detailed characterization of the CLNS1A gene and provide the exact position (6p12) and sequence data of CLNS1B, an intronless gene 91.3% homologous to the coding region of CLNS1A.
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Affiliation(s)
- U O Nagl
- Department of Physiology, University of Innsbruck, Fritz-Pregl-Strasse 3, A-6020, Innsbruck, Austria
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Laich A, Gschwentner M, Krick W, Nagl UO, Fürst J, Hofer S, Susanna A, Schmarda A, Deetjen P, Burckhardt G, Paulmichl M. ICln, a chloride channel cloned from kidney cells, is activated during regulatory volume decrease. Kidney Int 1997; 51:477-8. [PMID: 9027725 DOI: 10.1038/ki.1997.65] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- A Laich
- Department of Physiology, University of Innsbruck, Austria
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25
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Wöll E, Gschwentner M, Fürst J, Hofer S, Buemberger G, Jungwirth A, Frick J, Deetjen P, Paulmichl M. Fluorescence-optical measurements of chloride movements in cells using the membrane-permeable dye diH-MEQ. Pflugers Arch 1996; 432:486-93. [PMID: 8766008 DOI: 10.1007/s004240050160] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Fluorescence-optical measurements of the intracellular chloride concentration facilitate identification of chloride movements across the cell membrane of living cells. The two main dyes used for this purpose are 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ) and 6-methoxy-quinolyl acetoethyl ester (MQAE). The use of both substances is impaired by their poor membrane permeability and therefore limited loading of the cells to be studied. Here we report the use of 6-methoxy-N-ethylquinolinium iodide (MEQ), a chloride-sensitive dye for which a membrane-permeable form is easily prepared. This makes the loading procedure as easy as with the acetoxymethyl (AM) forms of other dyes for sensing intracellular ions. In addition, the original method, which described absolute concentration measurements of chloride in the cytosol, was modified in so far as only relative measurements were made. This avoids the known limitations of single wavelength excitation and emission dyes with respect to exact concentration measurements. Moreover, to enhance the signal-to-noise ratio the driving force for chloride was considerably increased by changing the original direction of the anion flux in the cells under investigation. We verified the method by using fibroblasts and activating ICln, a putative chloride channel cloned from epithelial cells and of paramount importance in the regulatory volume decrease in these cells. In the presence of SCN- the MEQ quench measured in NIH 3T3 fibroblasts is dramatically enhanced in hypotonically challenged cells compared with cells under isotonic conditions. Antisense oligodeoxynucleotides sensing ICln considerably impeded the swelling-induced chloride current (ICl) in NIH 3T3 fibroblasts. Accordingly, the chloride movement measured by the SCN- quench of the MEQ signal was significantly reduced. Similar results can be obtained in the presence of 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) or 4, 4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), two known blockers of chloride transport in the plasma membrane of a variety of cells. In conclusion, fluroscence-optical measurements using MEQ as the chloride-sensitive dye provide a reliable and easy-to-use method for measuring changes of the chloride flux across the cell membrane of living cells.
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Affiliation(s)
- E Wöll
- Department of Internal Medicine, University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria
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Fürst J, Fiebiger E, Mack D, Frick J, Rovan E. The effect of active immunization against gonadotropin-releasing hormone on the ultrastructure of the rat ventral prostate. Urol Res 1994; 22:107-13. [PMID: 7974913 DOI: 10.1007/bf00311001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
To evaluate the effects of active immunization against gonadotropin-releasing hormone (GnRH) on the ultrastructure of the rat ventral prostate, male Sprague-Dawley rats received three consecutive intramuscular injections of 10 micrograms/100 g body weight (D-Lys6)-GnRH-diphtheria toxoid conjugate (GnRH-DT vaccine). Following immunization, test animals developed sufficiently high antibody titres to block the pituitary gonadal axis. Consequently testosterone values dropped to the levels in castrates. This therapy leads to atrophy of the prostate. Following immunization a strong immunological response, indicating the presence of considerable amounts of a GnRH-like peptide, was observed in the ventral prostates as early as 14 days after the first injection of GnRH-DT. Immunoneutralisation of GnRH-like activity may contribute to the effects observed.
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Affiliation(s)
- J Fürst
- Institute of Zoology, University of Salzburg, Austria
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27
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28
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Stüttgen G, Fürst J, Hoffmann E. [The capillary microscopic picture of the nail wall and lip under intravenous infusion with nicotinic acid derivatives]. Med Welt 1969; 30:1654-8. [PMID: 5355656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Fürst J. [The gynecologic history]. Prensa Med Argent 1965; 52:1127-8. [PMID: 5844704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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