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Chatterjee P, Saha S, Mukhopadhyay D. Cell-Based Assay to Detect the Autoantibody Serostatus in Patients with Neuromyelitis Optica Spectrum Disorder (NMOSD). Methods Mol Biol 2024; 2761:121-133. [PMID: 38427234 DOI: 10.1007/978-1-0716-3662-6_10] [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] [Indexed: 03/02/2024]
Abstract
Cell-based assay (CBA) is an immunofluorescence assay that is extensively used for the confirmatory diagnosis of inflammatory demyelinating diseases of the central nervous system, like neuromyelitis optica spectrum disorder (NMOSD). Detecting the type of autoantibody present in the sera of the patients is the primary goal. CBA is the most sensitive and recommended detection method among all similar tools. Briefly, serum autoantibody is screened by transfecting specific cells seeded on cover glasses with full-length specific antigen fused with green fluorescent protein (GFP), followed by treating them with the patient serum used here as the source of primary antibody. The autoantibody-treated cells are further labeled with a rhodamine-conjugated secondary antibody. The co-localization of GFP and rhodamine is visualized by confocal microscopy, and the intensity of fluorescence is evaluated to determine the presence of autoantibody. A detailed protocol to screen antibodies against AQP4 and MOG in human sera using this method is described.
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Affiliation(s)
- Pallavi Chatterjee
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, A CI of Homi Bhabha National Institute, Kolkata, India
| | - Suparna Saha
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, A CI of Homi Bhabha National Institute, Kolkata, India
- NINDS, NIH, Bethesda, MD, USA
| | - Debashis Mukhopadhyay
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, A CI of Homi Bhabha National Institute, Kolkata, India.
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Barile B, Mola MG, Formaggio F, Saracino E, Cibelli A, Gargano CD, Mogni G, Frigeri A, Caprini M, Benfenati V, Nicchia GP. AQP4-independent TRPV4 modulation of plasma membrane water permeability. Front Cell Neurosci 2023; 17:1247761. [PMID: 37720545 PMCID: PMC10500071 DOI: 10.3389/fncel.2023.1247761] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 08/14/2023] [Indexed: 09/19/2023] Open
Abstract
Despite of the major role of aquaporin (AQP) water channels in controlling transmembrane water fluxes, alternative ways for modulating water permeation have been proposed. In the Central Nervous System (CNS), Aquaporin-4 (AQP4) is reported to be functionally coupled with the calcium-channel Transient-Receptor Potential Vanilloid member-4 (TRPV4), which is controversially involved in cell volume regulation mechanisms and water transport dynamics. The present work aims to investigate the selective role of TRPV4 in regulating plasma membrane water permeability in an AQP4-independent way. Fluorescence-quenching water transport experiments in Aqp4-/- astrocytes revealed that cell swelling rate is significantly increased upon TRPV4 activation and in the absence of AQP4. The biophysical properties of TRPV4-dependent water transport were therefore assessed using the HEK-293 cell model. Calcein quenching experiments showed that chemical and thermal activation of TRPV4 overexpressed in HEK-293 cells leads to faster swelling kinetics. Stopped-flow light scattering water transport assay was used to measure the osmotic permeability coefficient (Pf, cm/s) and activation energy (Ea, kcal/mol) conferred by TRPV4. Results provided evidence that although the Pf measured upon TRPV4 activation is lower than the one obtained in AQP4-overexpressing cells (Pf of AQP4 = 0.01667 ± 0.0007; Pf of TRPV4 = 0.002261 ± 0.0004; Pf of TRPV4 + 4αPDD = 0.007985 ± 0.0006; Pf of WT = 0.002249 ± 0.0002), along with activation energy values (Ea of AQP4 = 0.86 ± 0.0006; Ea of TRPV4 + 4αPDD = 2.73 ± 1.9; Ea of WT = 8.532 ± 0.4), these parameters were compatible with a facilitated pathway for water movement rather than simple diffusion. The possibility to tune plasma membrane water permeability more finely through TRPV4 might represent a protective mechanism in cells constantly facing severe osmotic challenges to avoid the potential deleterious effects of the rapid cell swelling occurring via AQP channels.
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Affiliation(s)
- Barbara Barile
- Department of Bioscience, Biotechnology and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Maria Grazia Mola
- Department of Bioscience, Biotechnology and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Formaggio
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Emanuela Saracino
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Bologna, Italy
| | - Antonio Cibelli
- Department of Bioscience, Biotechnology and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Concetta Domenica Gargano
- Department of Translational Biomedicine and Neuroscience (DiBraiN), School of Medicine, University of Bari Aldo Moro, Bari, Italy
| | - Guido Mogni
- Department of Bioscience, Biotechnology and Environment, University of Bari Aldo Moro, Bari, Italy
| | - Antonio Frigeri
- Department of Translational Biomedicine and Neuroscience (DiBraiN), School of Medicine, University of Bari Aldo Moro, Bari, Italy
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 840 Kennedy Center, Bronx, NY, United States
| | - Marco Caprini
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Valentina Benfenati
- Institute for Organic Synthesis and Photoreactivity (ISOF), National Research Council of Italy (CNR), Bologna, Italy
| | - Grazia Paola Nicchia
- Department of Bioscience, Biotechnology and Environment, University of Bari Aldo Moro, Bari, Italy
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 840 Kennedy Center, Bronx, NY, United States
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Seok JM, Cho W, Chung YH, Ju H, Kim ST, Seong JK, Min JH. Differentiation between multiple sclerosis and neuromyelitis optica spectrum disorder using a deep learning model. Sci Rep 2023; 13:11625. [PMID: 37468553 DOI: 10.1038/s41598-023-38271-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 07/06/2023] [Indexed: 07/21/2023] Open
Abstract
Multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) are autoimmune inflammatory disorders of the central nervous system (CNS) with similar characteristics. The differential diagnosis between MS and NMOSD is critical for initiating early effective therapy. In this study, we developed a deep learning model to differentiate between multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) using brain magnetic resonance imaging (MRI) data. The model was based on a modified ResNet18 convolution neural network trained with 5-channel images created by selecting five 2D slices of 3D FLAIR images. The accuracy of the model was 76.1%, with a sensitivity of 77.3% and a specificity of 74.8%. Positive and negative predictive values were 76.9% and 78.6%, respectively, with an area under the curve of 0.85. Application of Grad-CAM to the model revealed that white matter lesions were the major classifier. This compact model may aid in the differential diagnosis of MS and NMOSD in clinical practice.
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Affiliation(s)
- Jin Myoung Seok
- Department of Neurology, Soonchunhyang University Hospital Cheonan, Soonchunhyang University College of Medicine, Cheonan, South Korea
| | - Wanzee Cho
- Department of Artificial Intelligence, Korea University, Seoul, South Korea
| | - Yeon Hak Chung
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
- Department of Neurology, Neuroscience Center, Samsung Medical Center, Seoul, South Korea
| | - Hyunjin Ju
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
- Department of Neurology, Neuroscience Center, Samsung Medical Center, Seoul, South Korea
| | - Sung Tae Kim
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Joon-Kyung Seong
- Department of Artificial Intelligence, Korea University, Seoul, South Korea.
- School of Biomedical Engineering, Korea University, Seoul, South Korea.
- Interdisciplinary Program in Precision Public Health, Korea University, Seoul, South Korea.
| | - Ju-Hong Min
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
- Department of Neurology, Neuroscience Center, Samsung Medical Center, Seoul, South Korea.
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Sungkyunkwan University, 50 Irwon-dong, Gangnam-gu, Seoul, 135-710, South Korea.
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4
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Cortese R, Prados Carrasco F, Tur C, Bianchi A, Brownlee W, De Angelis F, De La Paz I, Grussu F, Haider L, Jacob A, Kanber B, Magnollay L, Nicholas RS, Trip A, Yiannakas M, Toosy AT, Hacohen Y, Barkhof F, Ciccarelli O. Differentiating Multiple Sclerosis From AQP4-Neuromyelitis Optica Spectrum Disorder and MOG-Antibody Disease With Imaging. Neurology 2023; 100:e308-e323. [PMID: 36192175 PMCID: PMC9869760 DOI: 10.1212/wnl.0000000000201465] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 09/09/2022] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND AND OBJECTIVES Relapsing-remitting multiple sclerosis (RRMS), aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) may have overlapping clinical features. There is an unmet need for imaging markers that differentiate between them when serologic testing is unavailable or ambiguous. We assessed whether imaging characteristics typical of MS discriminate RRMS from AQP4-NMOSD and MOGAD, alone and in combination. METHODS Adult, nonacute patients with RRMS, APQ4-NMOSD, and MOGAD and healthy controls were prospectively recruited at the National Hospital for Neurology and Neurosurgery (London, United Kingdom) and the Walton Centre (Liverpool, United Kingdom) between 2014 and 2019. They underwent conventional and advanced brain, cord, and optic nerve MRI and optical coherence tomography (OCT). RESULTS A total of 91 consecutive patients (31 RRMS, 30 APQ4-NMOSD, and 30 MOGAD) and 34 healthy controls were recruited. The most accurate measures differentiating RRMS from AQP4-NMOSD were the proportion of lesions with the central vein sign (CVS) (84% vs 33%, accuracy/specificity/sensitivity: 91/88/93%, p < 0.001), followed by cortical lesions (median: 2 [range: 1-14] vs 1 [0-1], accuracy/specificity/sensitivity: 84/90/77%, p = 0.002) and white matter lesions (mean: 39.07 [±25.8] vs 9.5 [±14], accuracy/specificity/sensitivity: 78/84/73%, p = 0.001). The combination of higher proportion of CVS, cortical lesions, and optic nerve magnetization transfer ratio reached the highest accuracy in distinguishing RRMS from AQP4-NMOSD (accuracy/specificity/sensitivity: 95/92/97%, p < 0.001). The most accurate measures favoring RRMS over MOGAD were white matter lesions (39.07 [±25.8] vs 1 [±2.3], accuracy/specificity/sensitivity: 94/94/93%, p = 0.006), followed by cortical lesions (2 [1-14] vs 1 [0-1], accuracy/specificity/sensitivity: 84/97/71%, p = 0.004), and retinal nerve fiber layer thickness (RNFL) (mean: 87.54 [±13.83] vs 75.54 [±20.33], accuracy/specificity/sensitivity: 80/79/81%, p = 0.009). Higher cortical lesion number combined with higher RNFL thickness best differentiated RRMS from MOGAD (accuracy/specificity/sensitivity: 84/92/77%, p < 0.001). DISCUSSION Cortical lesions, CVS, and optic nerve markers achieve a high accuracy in distinguishing RRMS from APQ4-NMOSD and MOGAD. This information may be useful in clinical practice, especially outside the acute phase and when serologic testing is ambiguous or not promptly available. CLASSIFICATION OF EVIDENCE This study provides Class II evidence that selected conventional and advanced brain, cord, and optic nerve MRI and OCT markers distinguish adult patients with RRMS from AQP4-NMOSD and MOGAD.
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Affiliation(s)
- Rosa Cortese
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Ferran Prados Carrasco
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Carmen Tur
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Alessia Bianchi
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Wallace Brownlee
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Floriana De Angelis
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Isabel De La Paz
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Francesco Grussu
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Lukas Haider
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Anu Jacob
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Baris Kanber
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Lise Magnollay
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Richard S Nicholas
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Anand Trip
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Marios Yiannakas
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Ahmed T Toosy
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Yael Hacohen
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Frederik Barkhof
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands
| | - Olga Ciccarelli
- From the Department of Neuroinflammation (R.C., F.P.C., C.T., A.B., W.B., F.D.A., I.D.L.P., F.G., L.H., L.M., A.T., M.Y., A.T.T., Y.H.R.C.P.C.H., F.B., O.C.), Queen Square MS Centre, UCL Queen Square Institute of Neurology, Faculty of Brain Science, University College of London; Department of Medicine (R.C.), Surgery and Neuroscience, University of Siena, Italy; Department of Medical Physics and Biomedical Engineering (F.P.C., B.K., F.B.), Centre for Medical Imaging Computing, University College of London; Universitat Oberta de Catalunya (F.P.C.), Barcelona, Spain; MS Centre of Catalonia (Cemcat) (C.T.), Vall d'Hebron Institute of Research, Spain; Radiomics Group (F.G.), Vall d'Hebron Institute of Oncology, Vall d'Hebron Barcelona Barcelona, Spain; Department of Biomedical Imaging and Image Guided Therapy (L.H.), Medical University of Vienna, Austria; NMO Clinical Service at the Walton Centre (A.J.), Liverpool, United Kingdom; Division of Multiple Sclerosis and Autoimmune Neurology (A.J.), Neurological Institute, Cleveland Clinic Abu Dhabi, United Arab Emirates; Division of Brain Sciences (R.S.N.), Department of Medicine, Imperial College London; National Institute for Health Research (NIHR) (A.T., F.B., O.C.), University College London Hospitals (UCLH), Biomedical Research Centre; and Department of Radiology and Nuclear Medicine (F.B.), Amsterdam University Medical Centre, the Netherlands.
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5
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Pati R, Palazzo C, Valente O, Abbrescia P, Messina R, Surdo NC, Lefkimmiatis K, Signorelli F, Nicchia GP, Frigeri A. The Readthrough Isoform AQP4ex Is Constitutively Phosphorylated in the Perivascular Astrocyte Endfeet of Human Brain. Biomolecules 2022; 12:633. [PMID: 35625560 PMCID: PMC9138620 DOI: 10.3390/biom12050633] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/17/2022] [Accepted: 04/22/2022] [Indexed: 02/03/2023] Open
Abstract
AQP4ex is a recently discovered isoform of AQP4 generated by a translational readthrough mechanism. It is strongly expressed at the astrocyte perivascular endfeet as a component of the supramolecular membrane complex, commonly called orthogonal array of particles (OAP), together with the canonical isoforms M1 and M23 of AQP4. Previous site-directed mutagenesis experiments suggested the potential role of serine331 and serine335, located in the extended peptide of AQP4ex, in water channel activity by phosphorylation. In the present study we evaluated the effective phosphorylation of human AQP4ex. A small scale bioinformatic analysis indicated that only Ser335 is conserved in human, mouse and rat AQP4ex. The phosphorylation site of Ser335 was assessed through generation of phospho-specific antibodies in rabbits. Antibody specificity was first evaluated in binding phosphorylated peptide versus its unphosphorylated analog by ELISA, which was further confirmed by site-directed mutagenesis experiments. Western blot and immunofluorescence experiments revealed strong expression of phosphorylated AQP4ex (p-AQP4ex) in human brain and localization at the perivascular astrocyte endfeet in supramolecular assemblies identified by BN/PAGE experiments. All together, these data reveal, for the first time, the existence of a phosphorylated form of AQP4, at Ser335 in the extended sequence exclusive of AQP4ex. Therefore, we anticipate an important physiological role of p-AQP4ex in human brain water homeostasis.
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Affiliation(s)
- Roberta Pati
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, School of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy; (R.P.); (C.P.); (O.V.); (P.A.); (R.M.); (F.S.)
| | - Claudia Palazzo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, School of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy; (R.P.); (C.P.); (O.V.); (P.A.); (R.M.); (F.S.)
| | - Onofrio Valente
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, School of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy; (R.P.); (C.P.); (O.V.); (P.A.); (R.M.); (F.S.)
| | - Pasqua Abbrescia
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, School of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy; (R.P.); (C.P.); (O.V.); (P.A.); (R.M.); (F.S.)
| | - Raffaella Messina
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, School of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy; (R.P.); (C.P.); (O.V.); (P.A.); (R.M.); (F.S.)
| | - Nicoletta Concetta Surdo
- Foundation for Advanced Biomedical Research, Veneto Institute of Molecular Medicine, 35129 Padova, Italy; (N.C.S.); (K.L.)
- Neuroscience Institute, National Research Council of Italy (CNR), 35129 Padova, Italy
| | - Konstantinos Lefkimmiatis
- Foundation for Advanced Biomedical Research, Veneto Institute of Molecular Medicine, 35129 Padova, Italy; (N.C.S.); (K.L.)
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
| | - Francesco Signorelli
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, School of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy; (R.P.); (C.P.); (O.V.); (P.A.); (R.M.); (F.S.)
| | - Grazia Paola Nicchia
- Department of Bioscience, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, 70124 Bari, Italy;
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 840 Kennedy Center, Bronx, NY 10461, USA
| | - Antonio Frigeri
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, School of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy; (R.P.); (C.P.); (O.V.); (P.A.); (R.M.); (F.S.)
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 840 Kennedy Center, Bronx, NY 10461, USA
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Simone M, Palazzo C, Mastrapasqua M, Bollo L, Pompamea F, Gabellone A, Marzulli L, Giordano P, De Giacomo A, Frigeri A, Ruggieri M, Margari L. Serum Neurofilament Light Chain Levels and Myelin Oligodendrocyte Glycoprotein Antibodies in Pediatric Acquired Demyelinating Syndromes. Front Neurol 2021; 12:754518. [PMID: 34867740 PMCID: PMC8635987 DOI: 10.3389/fneur.2021.754518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 10/07/2021] [Indexed: 11/16/2022] Open
Abstract
Introduction: The relationship between serum neurofilament light chain (sNfL) and myelin oligodendrocyte glycoprotein antibody (MOG-Ab) status has not been yet investigated in children with the acquired demyelinating syndrome (ADS). Objective and Methods: The sNfL levels and MOG-Abs were measured by ultrasensitive single-molecule array and cell-based assay in a cohort of 37 children with ADS and negativity for serum anti-aquaporin 4 (AQP4) antibodies. The sNfL levels were compared in MOG-Ab+/MOG-Ab– and in two subgroups MOG-Ab+ with/without encephalopathy. Results: About 40% ADS resulted in MOG-Ab+. MOG-Ab+ were younger at sampling (median = 9.8; range = 2.17–17.5 vs. 14.7/9–17; p = 0.002) with lower frequency of cerebrospinal fluid oligoclonal bands positivity (27% vs. 70%; p = 0.013) compared to MOG-Ab–. About 53% of MOG-Ab+ presented encephalopathy at onset, 1/22 of MOG-Ab– (p = 0.0006). Higher sNfL levels (p = 0.0001) were found in MOG-Ab+ (median/range = 11.11/6.8–1,129) and MOG-Ab– (median/range = 11.6/4.3–788) compared to age-matched controls (median/range = 2.98/1–4.53), without significant difference. MOG-Ab+ with encephalopathy resulted significantly younger at sampling (median/range: 4.5/2.17–11.17 vs. 14.16/9.8–17.5; p = 0.004), had higher sNfL levels (median/range:75.24/9.1–1,129 vs. 10.22/6.83–50.53; p = 0.04), and showed a trend for higher MOG-Ab titer (0.28/0.04–0.69 vs. 0.05/0.04–0.28; p = 0.1) in comparison to those without encephalopathy. Discussion: We confirmed high sNfL levels in pediatric ADS independently from the MOG-Ab status. Encephalopathy at onset is associated more frequently with MOG Ab+ children with higher sNfL levels and MOG titer. These findings suggest a role of acute demyelination in association with axonal damage in the pathogenesis of encephalopathy in pediatric ADS.
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Affiliation(s)
- Marta Simone
- Department of Biomedical Sciences and Human Oncology, School of Medicine, University of Bari Aldo Moro, Bari, Italy
| | - Claudia Palazzo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Mariangela Mastrapasqua
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Luca Bollo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Pompamea
- Department of Biomedical Sciences and Human Oncology, School of Medicine, University of Bari Aldo Moro, Bari, Italy
| | - Alessandra Gabellone
- Department of Biomedical Sciences and Human Oncology, School of Medicine, University of Bari Aldo Moro, Bari, Italy
| | - Lucia Marzulli
- Department of Biomedical Sciences and Human Oncology, School of Medicine, University of Bari Aldo Moro, Bari, Italy
| | - Paola Giordano
- Department of Biomedical Sciences and Human Oncology, School of Medicine, University of Bari Aldo Moro, Bari, Italy
| | - Andrea De Giacomo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Antonio Frigeri
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Maddalena Ruggieri
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Lucia Margari
- Department of Biomedical Sciences and Human Oncology, School of Medicine, University of Bari Aldo Moro, Bari, Italy
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Pandit L, Malli C, D'Cunha A, Sudhir A. Overcoming the challenges in diagnosis of AQP4-IgG positive neuromyelitis optica spectrum disorders in resource poor settings using an indigenized and cost effective cell based assay. J Neuroimmunol 2021; 360:577706. [PMID: 34507014 DOI: 10.1016/j.jneuroim.2021.577706] [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: 04/15/2021] [Revised: 08/26/2021] [Accepted: 08/30/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Diagnosis of neuromyelitis optica spectrum disorders (NMOSD) in India is hindered by limited access to cost effective and sensitive assays for detection of aquaporin-4 antibody (AQP4-IgG) in India. OBJECTIVE To develop a cost effective, sensitive, cell based assay (CBA) for detection of AQP4-IgG and to evaluate the serological status in patients with NMOSD diagnosed by 2015 diagnostic criteria. METHOD Stably transfected Chinese hamster ovary (CHO) cell line expressing aquaporin M23 isomer was established. A fixed CBA was developed and validated in 381 samples including clinically definite NMOSD (n = 87), high risk NMOSD (n = 51), other demyelinating disorders (n = 92), other neurological disorders (n = 51) and healthy volunteers (n = 100). We tested the same samples again using a commercially available CBA and compared the results. All assays were performed by 2 independent investigators blinded to clinical and serological status. RESULTS Our "in house"(Mangalore) assay showed sensitivity of 81.6% (95% CI 71.86-89.11%) for clinically definite NMOSD and 29.41% (95% CI 17.50-43.8%) for high risk NMOSD. Specificity was 100% for both groups. Both assays showed similar results for 67/ 87 (77.01%) patients with definite NMOSD while 4 samples tested positive by our assay alone (Cohen's kappa coefficient [K] - 0.86). Among the high risk group 14/51 (27.5%) samples showed similar results, one patient additionally was positive by the Mangalore assay (K - 0.95).
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Affiliation(s)
- Lekha Pandit
- Center for Advanced Neurological Research, KS Hegde Medical Academy, Nitte University, Mangalore, India.
| | - Chaithra Malli
- Center for Advanced Neurological Research, KS Hegde Medical Academy, Nitte University, Mangalore, India
| | - Anitha D'Cunha
- Center for Advanced Neurological Research, KS Hegde Medical Academy, Nitte University, Mangalore, India
| | - Akshatha Sudhir
- Center for Advanced Neurological Research, KS Hegde Medical Academy, Nitte University, Mangalore, India
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Bollo L, Iaffaldano P, Ruggieri M, Palazzo C, Mastrapasqua M, Manni A, Paolicelli D, Frigeri A, Trojano M. Longitudinal Evaluation of Serum MOG-IgG and AQP4-IgG Antibodies in NMOSD by a Semiquantitative Ratiometric Method. Front Neurol 2021; 12:633115. [PMID: 33763015 PMCID: PMC7982799 DOI: 10.3389/fneur.2021.633115] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 02/01/2021] [Indexed: 11/22/2022] Open
Abstract
Background and purpose: Immunoadsorption (IA) is an antibody-depleting therapy used to treat neuromyelitis optica spectrum disorder (NMOSD) associated to antiaquaporin 4 (anti-AQP4-IgG) and antimyelin oligodendrocyte glycoprotein (anti-MOG-IgG) serum autoantibodies. Our aim was to evaluate longitudinal changes of serum MOG-IgG and AQP4-IgG antibody titer and to correlate it with the clinical status. Methods: Autoantibody titer and clinical features of two MOG-IgG+/AQP4-IgG– and two AQP4-IgG+/MOG-IgG– patients with NMOSD were collected at baseline (T0), after 6 IA courses (T1), and then 2 weeks (T2) and 6 months after treatment (T3). A fluorescent ratiometric assay was used for a quantitative detection of MOG and AQP4 antibodies, based on HEK-293 cells transfected with the full-length hMOG fused to GFP or h-AQP4-M23 isoform fused to m-cherry, respectively. We defined the antibody titer as MOG quantitative ratio (MOGqr) and AQP4 quantitative ratio (AQP4qr). Results: In Case 1, the MOGqr dropped from 0.98 at T0 to 0.14 at T3, and in Case 2, it decreased from 0.96 at T0 to undetectable at T3. In Case3, the AQP4qr remained high: 0.90 at T0 and 0.92 at T3. In Case 4, the AQP4qr decreased from 0.50 at T0 to undetectable at T3. Complete recovery was found in Cases 1, 2, and 4. Conclusions: Semiquantitative ratiometric method accurately detects even slight variation of MOG-IgG and AQP4-IgG titer, suggesting it may be useful to monitor the antibody titer during the disease course and maintenance immunotherapy.
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Affiliation(s)
- Luca Bollo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Pietro Iaffaldano
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Maddalena Ruggieri
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Claudia Palazzo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Mariangela Mastrapasqua
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Alessia Manni
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Damiano Paolicelli
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Antonio Frigeri
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Maria Trojano
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
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Thoman ME, McKarns SC. Metabolomic Profiling in Neuromyelitis Optica Spectrum Disorder Biomarker Discovery. Metabolites 2020; 10:metabo10090374. [PMID: 32961928 PMCID: PMC7570337 DOI: 10.3390/metabo10090374] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/04/2020] [Accepted: 09/12/2020] [Indexed: 12/21/2022] Open
Abstract
There is no specific test for diagnosing neuromyelitis optica spectrum disorder (NMOSD), a disabling autoimmune disease of the central nervous system. Instead, diagnosis relies on ruling out other related disorders with overlapping clinical symptoms. An urgency for NMOSD biomarker discovery is underscored by adverse responses to treatment following misdiagnosis and poor prognosis following the delayed onset of treatment. Pathogenic autoantibiotics that target the water channel aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) contribute to NMOSD pathology. The importance of early diagnosis between AQP4-Ab+ NMOSD, MOG-Ab+ NMOSD, AQP4-Ab− MOG-Ab− NMOSD, and related disorders cannot be overemphasized. Here, we provide a comprehensive data collection and analysis of the currently known metabolomic perturbations and related proteomic outcomes of NMOSD. We highlight short chain fatty acids, lipoproteins, amino acids, and lactate as candidate diagnostic biomarkers. Although the application of metabolomic profiling to individual NMOSD patient care shows promise, more research is needed.
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Affiliation(s)
- Maxton E. Thoman
- Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA;
- Laboratory of TGF-β Biology, Epigenetics, and Cytokine Regulation, Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA
| | - Susan C. McKarns
- Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA;
- Laboratory of TGF-β Biology, Epigenetics, and Cytokine Regulation, Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA
- Department of Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212, USA
- Correspondence:
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10
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Jitprapaikulsan J, Fryer JP, Majed M, Smith CY, Jenkins SM, Cabre P, Hinson SR, Weinshenker BG, Mandrekar J, Chen JJ, Lucchinetti CF, Jiao Y, Segan J, Schmeling JE, Mills J, Flanagan EP, McKeon A, Pittock SJ. Clinical utility of AQP4-IgG titers and measures of complement-mediated cell killing in NMOSD. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2020; 7:7/4/e727. [PMID: 35413004 PMCID: PMC7286655 DOI: 10.1212/nxi.0000000000000727] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/15/2020] [Indexed: 11/15/2022]
Abstract
ObjectiveTo investigate whether aquaporin-4–immunoglobulin G (AQP4-IgG) titers and measures of complement-mediated cell killing are clinically useful to predict the occurrence of relapse, relapse severity, and/or disability in neuromyelitis optica spectrum disorder (NMOSD).MethodsWe studied 336 serial serum specimens from 82 AQP4-lgG–seropositive patients. NMOSD activity at blood draw was defined as preattack (24 [7.1%], drawn within 30 days preceding an attack), attack (108 [32.1%], drawn on attack onset or within 30 days after), or remission (199 [59.2%], drawn >90 days after attack onset and >30 days preceding a relapse). For each specimen, we documented the attack type and severity and immunotherapy status. Complement-mediated cell killing was quantitated by flow cytometry using an M23-AQP4 cell-based assay.ResultsThe estimated logarithmic means of AQP4-IgG titers in preattack, attack, and remission samples were 3.302, 3.657, and 3.458, respectively, p = 0.21. Analyses of 81 attack/remission pairs in 42 patients showed no significant titer differences (3.736 vs 3.472, p = 0.15). Analyses of 13 preattack/attack pairs in 9 patients showed no significant titer differences (3.994 vs 3.889, p = 0.67). Of 5 patients who converted to seronegative status, 2 continued to have attacks. Titers for major and minor attacks (n = 70) were not significantly different (3.905 vs 3.676, p = 0.47). Similarly, measures (titers) of complement-mediated cell killing were not significantly associated with disease course, attack severity, or disability at 5 years.Conclusions and relevanceAQP4-IgG titer and complement-mediated cell killing lack significant prognostic or predictive utility in NMOSD. Although titers may drop in the setting of immunotherapy, seroconversion to negative status does not preclude ongoing clinical attacks.Classification of evidenceThis study provides Class II evidence that in patients with NMOSD, AQP4-IgG titers and measures of complement-mediated cell killing activity do not predict relapses, relapse severity, or disability.
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Affiliation(s)
- Jiraporn Jitprapaikulsan
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - James P Fryer
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Masoud Majed
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Carin Y Smith
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Sarah M Jenkins
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Philippe Cabre
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Shannon R Hinson
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Brian G Weinshenker
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Jay Mandrekar
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - John J Chen
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Claudia F Lucchinetti
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Yujuan Jiao
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Jessica Segan
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - John E Schmeling
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - John Mills
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Eoin P Flanagan
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Andrew McKeon
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN
| | - Sean J Pittock
- From the Departments of Neurology (J.J., M.M., B.G.W., C.F.L., Y.J., E.P.F., A.M., S.J.P.), Laboratory Medicine and Pathology (J.J., J.P.F., S.R.H., J.E.S., J. Mills, A.M., S.J.P.), Health Sciences Research (C.Y.S., S.M.J., J. Mandrekar), Mayo Clinic, Rochester, MN; Department of Neurology (P.C.), Fort-de-France University Hospital Center, Pierre Zobda Quitman Hospital, Martinique; Center for MS and Autoimmune Neurology (B.G.W., J.J.C., C.F.L., J. S., J. Mills, E.P.F., A.M., S.J.P.), and Department of Ophthalmology (J.J.C.), Mayo Clinic, Rochester, MN.
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11
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Wu YF, Sytwu HK, Lung FW. Polymorphisms in the Human Aquaporin 4 Gene Are Associated With Schizophrenia in the Southern Chinese Han Population: A Case-Control Study. Front Psychiatry 2020; 11:596. [PMID: 32676041 PMCID: PMC7333661 DOI: 10.3389/fpsyt.2020.00596] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 06/09/2020] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND In psychiatric illness, pathogenic role of neuroinflammation has been supported by multiple lines of evidence. Astrocytes contribute to the blood-brain barrier (BBB) with formation of the "glymphatic" drainage system of the central nervous system (CNS) through perivascular processes. Found primarily at the end-feet of astrocytes, the aquaporin 4 (AQP4) gene has been suspected to play putative roles in the development of psychiatric disorders as well as the clearance of the glymphatic system. However, there remain many uncertainties because of the limited research on AQP4. The present study is focused on the association between AQP4 gene polymorphisms and schizophrenia (SCZ) in the Southern Chinese Han population. METHODS Two hundred ninety-two patients and 100 healthy controls were enrolled in this study. To study the relationship of AQP4 gene polymorphisms and SCZ, genetic information was drawn from a cohort of 100 healthy controls and 100 matched patients with SCZ of Southern Han Chinese descent. Comparisons of the allele and genotype distributions between control and case groups were made using the χ2 test. Two-group comparisons were made to assess the linkage equilibrium and haplotype. RESULTS Three SNPs were found. In comparison to healthy controls, patients had higher T-allele frequencies at rs1058424 and G-allele frequencies at rs3763043 (p = 0.043 and p = 0.045, respectively). Furthermore, there is an association between the decreased risk of SCZ and the AA genotype at both rs1058424 (p = 0.021, OR = 2.04) and rs3763043 (p = 0.018, OR = 2.25) The TCG haplotype (p = 0.036) was associated with a potential risk of SCZ, while the ACA haplotype (p = 0.0007) was associated with a decreased risk of SCZ and retained statistical significance after Bonferroni correction (p = 0.006). CONCLUSIONS An etiological reference for SCZ is provided by the association between AQP4 gene polymorphisms and SCZ in Southern Han Chinese population.
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Affiliation(s)
- Yung-Fu Wu
- Department of Psychiatry, Beitou Branch, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.,Graduate Institute of Medical Science, National Defense Medical Center, Taipei, Taiwan
| | - Huey-Kang Sytwu
- Department of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - For-Wey Lung
- Graduate Institute of Medical Science, National Defense Medical Center, Taipei, Taiwan.,Department of Psychiatry, Calo Psychiatric Center, Pingtung County, Taiwan
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12
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Prain K, Woodhall M, Vincent A, Ramanathan S, Barnett MH, Bundell CS, Parratt JDE, Silvestrini RA, Bukhari W, Brilot F, Waters P, Broadley SA. AQP4 Antibody Assay Sensitivity Comparison in the Era of the 2015 Diagnostic Criteria for NMOSD. Front Neurol 2019; 10:1028. [PMID: 31636597 PMCID: PMC6787171 DOI: 10.3389/fneur.2019.01028] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 09/10/2019] [Indexed: 11/24/2022] Open
Abstract
We have compared five different assays for antibodies to aquaporin-4 in 181 cases of suspected Neuromyelitis optica spectrum disorders (NMOSD) and 253 controls to assess their relative utility. As part of a clinically-based survey of NMOSD in Australia and New Zealand, cases of suspected NMOSD were referred from 23 centers. Clinical details and magnetic imaging were reviewed and used to apply the 2015 IPND diagnostic criteria. In addition, 101 age- and sex-matched patients with multiple sclerosis were referred. Other inflammatory disease (n = 49) and healthy controls (n = 103) were also recruited. Samples from all participants were tested using tissue-based indirect immunofluorescence assays and a subset were tested using four additional ELISA and cell-based assays. Antibodies to myelin oligodendrocyte glycoprotein (MOG) were also assayed. All aquaporin-4 antibody assays proved to be highly specific. Sensitivities ranged from 60 to 94%, with cell-based assays having the highest sensitivity. Antibodies to MOG were detected in 8/79 (10%) of the residual suspected cases of NMOSD. Under the 2015 IPND diagnostic criteria for NMOSD, cell-based assays for aquaporin-4 are sensitive and highly specific, performing better than tissue-based and ELISA assays. A fixed cell-based assay showed near-identical results to a live-cell based assay. Antibodies to MOG account for only a small number of suspected cases.
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Affiliation(s)
- Kerri Prain
- Pathology Queensland Central Laboratory, Division of Immunology, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
| | - Mark Woodhall
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Angela Vincent
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Sudarshini Ramanathan
- Brain Autoimmunity Group, Kids Neuroscience Centre, Kids Research at the Children's Hospital, Westmead, NSW, Australia.,Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| | - Michael H Barnett
- Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| | - Christine S Bundell
- School of Biomedical Science, Medicine, University of Western Australia, Nedlands, WA, Australia.,PathWest Laboratory Medicine, Department of Immunology, QEII Medical Centre, Nedlands, WA, Australia
| | - John D E Parratt
- Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia.,Department of Neurology, Royal North Shore Hospital, Sydney, NSW, Australia
| | - Roger A Silvestrini
- Brain Autoimmunity Group, Kids Neuroscience Centre, Kids Research at the Children's Hospital, Westmead, NSW, Australia
| | - Wajih Bukhari
- School of Medicine, Gold Coast Campus, Griffith University, Southport, QLD, Australia.,Department of Neurology, Gold Coast University Hospital, Southport, QLD, Australia
| | | | - Fabienne Brilot
- Brain Autoimmunity Group, Kids Neuroscience Centre, Kids Research at the Children's Hospital, Westmead, NSW, Australia.,Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| | - Patrick Waters
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Simon A Broadley
- School of Medicine, Gold Coast Campus, Griffith University, Southport, QLD, Australia.,Department of Neurology, Gold Coast University Hospital, Southport, QLD, Australia
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13
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Palazzo C, Buccoliero C, Mola MG, Abbrescia P, Nicchia GP, Trojano M, Frigeri A. AQP4ex is crucial for the anchoring of AQP4 at the astrocyte end-feet and for neuromyelitis optica antibody binding. Acta Neuropathol Commun 2019; 7:51. [PMID: 30935410 PMCID: PMC6444679 DOI: 10.1186/s40478-019-0707-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 03/21/2019] [Indexed: 12/18/2022] Open
Abstract
Brain water homeostasis is essential for the appropriate control of neuronal activity. Furthermore, the encasement of the central nervous system (CNS) by a hard structure, greatly limits its tolerance for the volume changes occurring with acute brain edema, which quickly leads to severe damage or death. The recent discovery of the extended isoform of AQP4 (AQP4ex), generated by translational readthrough, revealed a potential new mechanism of water transport regulation and polarization at the blood-brain-barrier level. In the present study we used CRISPR/Cas9 technology to generate an AQP4ex−/− mouse model and evaluate the effect on the overall AQP4 expression, polarization, supramolecular organization in orthogonal arrays of particles (OAPs) and neuromyelitis optica (NMO-IgG) autoantibodies binding. AQP4ex removal did not cause a decrease in total AQP4 protein expression but completely suppressed the specific location of AQP4 at the astrocyte endfeet. Without AQP4ex, AQP4 was mislocalized and α-syntrophin expression, the selective partner for AQP4 localization, was partially altered. The supramolecular organization of AQP4 in OAPs was subtly altered. Indeed, the absence of AQP4ex reduced the size of AQP4-OAPs but the number of AQP4-OAP pools remained largely the same. More importantly, AQP4ex resulted critical for the binding of pathogenic human NMO-IgG autoantibodies to the brain. Indeed, the absence of AQP4ex completely abolished the binding of NMO-IgG at the perivascular astrocyte endfeet. This study provides the first direct evidence in vivo on the specific role of AQP4ex in AQP4 perivascular OAPs assembly and confinement and reveals AQP4ex as new and important player in neuromyelitis optica.
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14
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Pisani F, Simone L, Mola MG, De Bellis M, Mastrapasqua M, Ruggieri M, Trojano M, Nicchia GP, Svelto M, Frigeri A. Host-Cell Type Dependent Features of Recombinant Human Aquaporin-4 Orthogonal Arrays of Particles-New Insights for Structural and Functional Studies. Cells 2019; 8:cells8020119. [PMID: 30717425 PMCID: PMC6406603 DOI: 10.3390/cells8020119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 01/26/2019] [Accepted: 02/01/2019] [Indexed: 11/16/2022] Open
Abstract
The CNS plasma-membrane water channel aquaporin-4 (AQP4) is expressed as two major isoforms able to aggregate into supramolecular assemblies known as ‘orthogonal arrays of particles’ (OAPs). OAP subnanometric features are largely unknown mainly because a method for the expression, isolation, and crystallization of integral human OAPs has not been developed. Here, the human OAP-forming isoform M23-AQP4 was expressed in insect and mammalian cell lines and AQP4 and OAP features evaluated. Native size exclusion chromatography was employed to isolate and analyze authentically folded OAPs, and neuromyelitis optica (NMO)-specific sandwich ELISA was developed to test OAP-integrity. The results demonstrate that in insect cells most AQP4 remains intracellular and unfolded and that OAPs are largely disassembled after the detergent extraction step. In mammalian cells, AQP4 showed regular plasma membrane targeting and OAPs exhibited strong post-extraction stability. Starting from the mammalian cell expression system, we isolated authentically folded OAPs. Together these data suggest a new strategy for expressing and isolating integral recombinant human OAPs and providing new insights into the cell-type dependent OAP-assembly and post-extraction stability, potentially useful to design new approaches for structural and functional studies of OAP and for other plasma membrane proteins organized into supramolecular structures.
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Affiliation(s)
- Francesco Pisani
- Department of Bioscience, Biotechnologies and Biopharmaceutic, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
| | - Laura Simone
- Fondazione IRCCS Casa Sollievo della Sofferenza, Cancer Stem Cells Unit, 71013 San Giovanni Rotondo (FG), Italy.
| | - Maria Grazia Mola
- Department of Bioscience, Biotechnologies and Biopharmaceutic, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
| | - Manuela De Bellis
- Department of Bioscience, Biotechnologies and Biopharmaceutic, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
| | - Maria Mastrapasqua
- School of Medicine, Basic Medical Sciences, Neuroscience and Sense Organs, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
| | - Maddalena Ruggieri
- School of Medicine, Basic Medical Sciences, Neuroscience and Sense Organs, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
| | - Maria Trojano
- School of Medicine, Basic Medical Sciences, Neuroscience and Sense Organs, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
| | - Grazia Paola Nicchia
- Department of Bioscience, Biotechnologies and Biopharmaceutic, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
| | - Maria Svelto
- Department of Bioscience, Biotechnologies and Biopharmaceutic, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies, National Research Council, 70126 Bari, Italy.
| | - Antonio Frigeri
- School of Medicine, Basic Medical Sciences, Neuroscience and Sense Organs, Univ. of Bari "Aldo Moro", 70124 Bari, Italy.
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15
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Abstract
This document presents the guidelines for anti-aquaporin-4 (AQP4) antibody testing that has been developed following a consensus process built on questionnaire-based surveys, internet contacts, and discussions at workshops of the sponsoring Italian Association of Neuroimmunology (AINI) congresses. Essential clinical information on neuromyelitis optica spectrum disorders, indications and limits of anti-AQP4 antibody testing, instructions for result interpretation, and an agreed laboratory protocol (Appendix) are reported for the communicative community of neurologists and clinical pathologists.
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16
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Rosito S, Nicchia GP, Palazzo C, Lia A, Buccoliero C, Pisani F, Svelto M, Trojano M, Frigeri A. Supramolecular aggregation of aquaporin-4 is different in muscle and brain: correlation with tissue susceptibility in neuromyelitis optica. J Cell Mol Med 2017; 22:1236-1246. [PMID: 29055082 PMCID: PMC5783885 DOI: 10.1111/jcmm.13401] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 08/26/2017] [Indexed: 11/27/2022] Open
Abstract
Neuromyelitis optica (NMO) is an autoimmune demyelinating disease of the central nervous system (CNS) caused by autoantibodies (NMO‐IgG) against the water channel aquaporin‐4 (AQP4). Though AQP4 is also expressed outside the CNS, for example in skeletal muscle, patients with NMO generally do not show clinical/diagnostic evidence of skeletal muscle damage. Here, we have evaluated whether AQP4 supramolecular organization is at the basis of the different tissue susceptibility. Using immunofluorescence we found that while the sera of our cohort of patients with NMO gave typical perivascular staining in the CNS, they were largely negative in the skeletal muscle. This conclusion was obtained using human, rat and mouse skeletal muscle including the AQP4‐KO mouse. A biochemical analysis using a new size exclusion chromatography approach for AQP4 suprastructure fractionation revealed substantial differences in supramolecular AQP4 assemblies and isoform abundance between brain and skeletal muscle matching a lower binding affinity of NMO‐IgG to muscle compared to the brain. Super‐resolution microscopy analysis with g‐STED revealed different AQP4 organization in native tissues, while in the brain perivascular astrocyte endfoot membrane AQP4 was mainly organized in large interconnected and raft‐like clusters, in the sarcolemma of fast‐twitch fibres AQP4 aggregates often appeared as small, relatively isolated linear entities. In conclusion, our results provide evidence that AQP4 supramolecular structure is different in brain and skeletal muscle, which is likely to result in different tissues susceptibility to the NMO disease.
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Affiliation(s)
- Stefania Rosito
- Department of Bioscience, Biotechnologies and Biopharmaceutic, University of Bari "Aldo Moro", Bari, Italy
| | - Grazia Paola Nicchia
- Department of Bioscience, Biotechnologies and Biopharmaceutic, University of Bari "Aldo Moro", Bari, Italy.,Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Claudia Palazzo
- Department of Bioscience, Biotechnologies and Biopharmaceutic, University of Bari "Aldo Moro", Bari, Italy.,Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Anna Lia
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Cinzia Buccoliero
- Department of Bioscience, Biotechnologies and Biopharmaceutic, University of Bari "Aldo Moro", Bari, Italy.,Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Pisani
- Department of Bioscience, Biotechnologies and Biopharmaceutic, University of Bari "Aldo Moro", Bari, Italy
| | - Maria Svelto
- Department of Bioscience, Biotechnologies and Biopharmaceutic, University of Bari "Aldo Moro", Bari, Italy
| | - Maria Trojano
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Antonio Frigeri
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA.,Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, Bari, Italy
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17
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Long Y, Wu L, Zhong R, Ouyang X, Liang J, Gao C, Chen X, Qiu W, Chang Y, Wang Z, Ye J. Lesions of the posterior limb of the internal capsule in neuromyelitis optica spectrum disorder. Neurol Res 2017; 39:448-452. [PMID: 28262035 DOI: 10.1080/01616412.2017.1298230] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Youming Long
- Department of Neurology, The Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
| | - Linzhan Wu
- Department of Neurology, The Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
| | - Rong Zhong
- Department of Neurology, The Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
| | - Xiaoming Ouyang
- Department of Pathology, The Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
| | - Junyan Liang
- Department of Neurology, The Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
| | - Cong Gao
- Department of Neurology, The Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
| | - Xiaohui Chen
- Department of Emergency, The Second Affiliated Hospital of GuangZhou Medical University, GuangZhou, China
| | - Wei Qiu
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Yanyu Chang
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, People’s Republic of China
| | - Zhanhang Wang
- Department of Neurology, Guangdong 999 Brain Hospital, Guangzhou, People’s Republic of China
| | - Jinlong Ye
- Department of Neurology, Guangdong 999 Brain Hospital, Guangzhou, People’s Republic of China
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18
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Kim Y, Kim G, Kong BS, Lee JE, Oh YM, Hyun JW, Kim SH, Joung A, Kim BJ, Choi K, Kim HJ. Large-Scale in-House Cell-Based Assay for Evaluating the Serostatus in Patients with Neuromyelitis Optica Spectrum Disorder Based on New Diagnostic Criteria. J Clin Neurol 2017; 13:175-180. [PMID: 28271642 PMCID: PMC5392460 DOI: 10.3988/jcn.2017.13.2.175] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/22/2016] [Accepted: 12/23/2016] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND AND PURPOSE The detection of aquaporin 4-IgG (AQP4-IgG) is now a critical diagnostic criterion for neuromyelitis optica spectrum disorder (NMOSD). To evaluate the serostatus of NMOSD patients based on the 2015 new diagnostic criteria using a new in-house cell-based assay (CBA). METHODS We generated a stable cell line using internal ribosome entry site-containing bicistronic vectors, which allow the simultaneous expression of two proteins (AQP4 and green fluorescent protein) separately from the same RNA transcript. We performed in-house CBA using serum from 386 patients: 178 NMOSD patients diagnosed according to the new diagnostic criteria without AQP4-IgG, 63 high risk NMOSD patients presenting 1 of the 6 core clinical characteristics of NMOSD but not fulfilling dissemination in space, and 145 patients with other neurological diseases, including 66 with multiple sclerosis. The serostatus of 111 definite and high risk NMOSD patients were also tested using a commercial CBA kit with identical serum to evaluate the correlation between the 2 methods. All assays were performed by two independent and blinded investigators. RESULTS Our in-house assay yielded a specificity of 100% and sensitivities of 80% (142 of 178) and 76% (48 of 63) when detecting definite- and high risk NMOSD patients, respectively. The comparison with the commercial CBA kit revealed a correlation for 102 of the 111 patients: no correlation was present in 7 patients who were seronegative using the commercial method but seropositive using the in-house method, and in 2 patients who were seropositive using the commercial method but seronegative using the in-house method. CONCLUSIONS These results demonstrate that our in-house CBA is a highly specific and sensitive method for detecting AQP4-IgG in NMOSD patients.
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Affiliation(s)
- Yeseul Kim
- Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea.,Division of Translational and Clinical Research II, Research institute, National Cancer Center, Goyang, Korea
| | - Gayoung Kim
- Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea.,Division of Translational and Clinical Research II, Research institute, National Cancer Center, Goyang, Korea
| | - Byung Soo Kong
- Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea.,Division of Translational and Clinical Research II, Research institute, National Cancer Center, Goyang, Korea
| | - Ji Eun Lee
- Division of Translational and Clinical Research II, Research institute, National Cancer Center, Goyang, Korea.,Department of Biochemistry and Molecular Biology, and Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Yu Mi Oh
- Division of Translational and Clinical Research II, Research institute, National Cancer Center, Goyang, Korea.,Department of Biochemistry and Molecular Biology, and Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Jae Won Hyun
- Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea
| | - Su Hyun Kim
- Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea
| | - AeRan Joung
- Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea
| | - Byoung Joon Kim
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyungho Choi
- Department of Biochemistry and Molecular Biology, and Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Ho Jin Kim
- Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea.,Division of Translational and Clinical Research II, Research institute, National Cancer Center, Goyang, Korea.
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19
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Wang J, Tian Y, Shao Y, Feng H, Qin L, Xu W, Liu H, Xu Q, Wei S, Ma L. Comparison of spontaneous brain activity revealed by regional homogeneity in AQP4-IgG neuromyelitis optica-optic neuritis versus MOG-IgG optic neuritis patients: a resting-state functional MRI study. Neuropsychiatr Dis Treat 2017; 13:2669-2679. [PMID: 29123400 PMCID: PMC5661477 DOI: 10.2147/ndt.s145183] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
OBJECTIVE Many previous studies have demonstrated that neuromyelitis optica (NMO) patients have abnormalities of brain anatomy and function. However, differences in spontaneous brain activity between myelin oligodendrocyte glycoprotein (MOG)-IgG ON and aquaporin 4(AQP4)-neuromyelitis optica-optic neuritis (ON) remain unknown. In the current study, we investigated the brain neural homogeneity in MOG-IgG ON versus AQP4-IgG NMO-ON subjects by regional homogeneity (ReHo) method using magnetic resonance imaging (MRI). PATIENTS AND METHODS A total of 32 NMO-ON and ON subjects (21 with AQP4-IgG+NMO-ON and 11 with MOG-IgG+ON) and 34 healthy controls (HCs) closely matched for age were recruited, and scans were performed for all subjects. A one-way analysis of variance (ANOVA) was performed to determine the regions in which the ReHo was different across the three groups. NMO-ON and ON subjects were distinguished from HCs by a receiver operating characteristic (ROC) curve. The relationship between the mean ReHo in many brain regions and clinical features in NMO subjects was calculated by Pearson correlation analysis. RESULTS Compared with HCs, MOG-IgG+ON subjects had significantly decreased ReHo values in the posterior lobe of the left cerebellum and increased ReHo values in the left inferior frontal gyrus, right prefrontal gyrus, and left precentral/postcentral gyrus. AQP4-IgG+NMO-ON subjects showed higher ReHo values in the left inferior frontal gyrus and right middle temporal/occipital gyrus. Compared with MOG-IgG+ON subjects, AQP4-IgG+NMO-ON subjects had lower ReHo values in the posterior lobe of the right cerebellum. AQP4-Ig+NMO-ON subjects showed higher ReHo values in the left precentral/postcentral gyrus and right superior temporal gyrus. CONCLUSION AQP4-IgG+NMO-ON and MOG-IgG+ON subjects showed abnormal synchronized neuronal activity in many brain regions, which is consistent with deficits in visual, motor, and cognitive function. Furthermore, different patterns of synchronized neuronal activity occurred in the AQP4-IgG+NMO-ON and MOG-IgG+ON.
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Affiliation(s)
| | - Yuan Tian
- Department of Radiology, Chinese PLA General Hospital, Beijing
| | - Yi Shao
- Department of Ophthalmology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China
| | | | | | | | | | | | | | - Lin Ma
- Department of Radiology, Chinese PLA General Hospital, Beijing
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20
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Pisani F, Simone L, Gargano CD, De Bellis M, Cibelli A, Mola MG, Catacchio G, Frigeri A, Svelto M, Nicchia GP. Role of the H-bond between L53 and T56 for Aquaporin-4 epitope in Neuromyelitis Optica. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1859:368-376. [PMID: 28027883 DOI: 10.1016/j.bbamem.2016.12.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 12/13/2016] [Accepted: 12/23/2016] [Indexed: 11/29/2022]
Abstract
Aquaporin-4 (AQP4) is the CNS water channel organized into well-ordered protein aggregates called Orthogonal Arrays of Particles (OAPs). Neuromyelitis Optica (NMO) is an autoimmune disease caused by anti-OAP autoantibodies (AQP4-IgG). Molecular Dynamics (MD) simulations have identified an H-bond between L53 and T56 as the key for AQP4 epitope and therefore of potential interest for drug design in NMO field. In the present study, we have experimentally tested this MD-prediction using the classic mutagenesis approach. We substituted T56 with V56 and tested this mutant for AQP4 aggregates and AQP4-IgG binding. gSTED super-resolution microscopy showed that the mutation does not affect AQP4 aggregate dimension; immunofluorescence and cytofluorimetric analysis demonstrated its unaltered AQP4-IgG binding, therefore invalidating the MD-prediction. We later investigated whether AQP4, expressed in Sf9 insect and HEK-293F cells, is able to correctly aggregate before and after the purification steps usually applied to obtain AQP4 crystal. The results demonstrated that AQP4-IgG recognizes AQP4 expressed in Sf9 and HEK-293F cells by immunofluorescence even though BN-PAGE analysis showed that AQP4 forms smaller aggregates when expressed in insect cells compared to mammalian cell lines. Notably, after AQP4 purification, from both insect and HEK-293F cells, no aggregates are detectable by BN-PAGE and AQP4-IgG binding is impaired in sandwich ELISA assays. All together these results indicate that 1) the MD prediction under analysis is not supported by experimental data and 2) the procedure to obtain AQP4 crystals might affect its native architecture and, as a consequence, MD simulations. In conclusion, given the complex nature of the AQP4 epitope, MD might not be the suitable for molecular medicine advances in NMO.
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Affiliation(s)
- Francesco Pisani
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy
| | - Laura Simone
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy; IRCCS "Casa Sollievo della Sofferenza", Research Hospital, San Giovanni Rotondo, Foggia, Italy
| | - Concetta Domenica Gargano
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy
| | - Manuela De Bellis
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy
| | - Antonio Cibelli
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy
| | - Maria Grazia Mola
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy
| | - Giacomo Catacchio
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy
| | - Antonio Frigeri
- School of Medicine, Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari "Aldo Moro", Bari, Italy; Department of Neuroscience, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY, USA
| | - Maria Svelto
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy; Institute of Biomembranes and Bioenergetics, National Research Council, Bari, Italy; National Institute of Biostructures and Biosystems (INBB), Rome, Italy
| | - Grazia Paola Nicchia
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Centre of Excellence in Comparative Genomics, University of Bari "Aldo Moro", Bari, Italy; Department of Neuroscience, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY, USA.
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21
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Long Y, Liang J, Zhong R, Wu L, Qiu W, Lin S, Gao C, Chen X, Zheng X, Yang N, Gao M, Wang Z. Aquaporin-4 antibody in neuromyelitis optica: re-testing study in a large population from China. Int J Neurosci 2016; 127:790-799. [PMID: 27838939 DOI: 10.1080/00207454.2016.1259226] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Aquaporin-4 (AQP4) antibody sero-positivity is critically important in neuromyelitis optica (NMO). However, the sensitivity of different assays is highly variable. Repeating detection with a highly sensitive assay in a large population is necessary in the case of so-called negative NMO. METHODS Retrospective analysis where AQP4 antibodies were detected by commercial cell-based assay (CBA), in-house M23-CBA and in-house M1-CBA. RESULTS Of the 1011 serum samples, 206 (20.4%) were sero-positive by primary commercial CBA. In the retest, all 206 participants positive by primary commercial CBA also yielded positive results by in-house M23-CBA and the second commercial CBA again, but only 124 positive in in-house M1-CBA. Among the 805 participants negative by primary commercial CBA, 71 participants were positive for in-house M23-CBA, of which 20 participants were positive for the second commercial CBA, and none were positive by in-house M1-CBA. Of the 171 cerebral spinal fluid samples, 75 (43.9%) were positive by primary commercial CBA. All 75 participants positive by primary commercial CBA also yielded positive results by in-house M23-CBA and the second commercial CBA. Forty-nine (65.3%) of these 75 participants were positive by in-house M1-CBA. Among the 96 participants negative by primary commercial CBA, 15 participants were positive for in-house M23-CBA and none were positive by in-house M1-CBA and the second commercial CBA. CONCLUSIONS Different AQP4 isoforms in CBA result in different detection effects, and in-house M23-CBA is the most sensitive method. Some AQP4 antibody-negative NMO may be subject to diagnostic uncertainty due to limitations of the assays.
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Affiliation(s)
- Youming Long
- a Department of Neurology , The Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China.,b Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China , Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Junyan Liang
- a Department of Neurology , The Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China.,b Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China , Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Rong Zhong
- a Department of Neurology , The Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China.,b Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China , Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Linzhan Wu
- a Department of Neurology , The Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China.,b Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China , Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Wei Qiu
- c Department of Neurology , The Third Affiliated Hospital of Sun Yat-Sen University , Guangzhou , China
| | - Shaopeng Lin
- a Department of Neurology , The Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China.,b Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China , Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Cong Gao
- a Department of Neurology , The Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China.,b Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China , Institute of Neuroscience and the Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Xiaohui Chen
- d Department of Emergency , The Second Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Xueping Zheng
- e Department of Neurology , The Affiliated Hospital of Qingdao University , Qingdao , China
| | - Ning Yang
- f Department of Neurology , The Fifth Affiliated Hospital of GuangZhou Medical University , GuangZhou , China
| | - Min Gao
- g Department of Neurology , The Second Chinese Medicine Hospital of Guangdong Province , Guangzhou , China
| | - Zhanhang Wang
- h Department of Neurology , Guangdong 999 Brain Hospital , Guangzhou , China
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22
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Tuller F, Holzer H, Schanda K, Aboulenein-Djamshidian F, Höftberger R, Khalil M, Seifert-Held T, Leutmezer F, Berger T, Reindl M. Characterization of the binding pattern of human aquaporin-4 autoantibodies in patients with neuromyelitis optica spectrum disorders. J Neuroinflammation 2016; 13:176. [PMID: 27371173 PMCID: PMC4930584 DOI: 10.1186/s12974-016-0642-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 06/24/2016] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND The discovery of a highly specific antibody against the aquaporin-4 (AQP4) water channel (AQP4-IgG) unified the spectrum of neuromyelitis optica spectrum disorders (NMOSD), which are considered to be antibody-mediated autoimmune diseases. The AQP4 water channel is located on astrocytic end-feet processes and consists of six transmembrane helical domains forming three extracellular loops A, C, and E in which defined amino acids were already proven to be critical for AQP4-IgG binding. However, the clinical relevance of these findings is unclear. Therefore, we have characterized the epitope specificity of AQP4-IgG-positive NMOSD patients. METHODS We established a cell-based flow cytometry assay for the quantitative detection of AQP4-IgG-positive serum samples. Human embryonic kidney (HEK) cells were transiently transfected with an EmGFP-tagged AQP4-M23, AQP4-M1, or six AQP4-M23 extracellular loop mutants including two mutations in loop A (serial AA substitution, insertion of a myc-tag), two in loop C (N153Q, insertion of a myc-tag), and two in loop E (H230G, insertion of a myc-tag). Fourty-seven baseline and 49 follow-up serum samples and six paired cerebrospinal fluid (CSF) baseline samples of 47 AQP4-IgG-positive Austrian NMOSD patients were then tested for their binding capability to AQP4-M1 and AQP4-M23 isoforms and these six extracellular loop mutants. RESULTS Overall, we could identify two broad patterns of antibody recognition based on differential sensitivity to mutations in extracellular loop A. Pattern A was characterized by reduced binding to the two mutations in loop A, whereas pattern B had only partial or no reduced binding to these mutations. These two patterns were not associated with significant differences in demographic and clinical parameters or serum titers in this retrospective study. Interestingly, we found a change of AQP4-IgG epitope recognition pattern in seven of 20 NMOSD patients with available follow-up samples. Moreover, we found different binding patterns in five of six paired CSF versus serum samples, with a predominance of pattern A in CSF. CONCLUSIONS Our study demonstrates that AQP4-IgG in sera of NMOSD patients show distinct patterns of antibody recognition. The clinical and diagnostic relevance of these findings have to be addressed in prospective studies.
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Affiliation(s)
- Friederike Tuller
- Clinical Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Hannah Holzer
- Clinical Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Kathrin Schanda
- Clinical Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Fahmy Aboulenein-Djamshidian
- Department of Neurology, Karl Landsteiner Institute for Neuroimmunological and Neurodegenerative Disorders, Sozialmedizinisches Zentrum Ost Donauspital, Vienna, Austria
| | - Romana Höftberger
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Michael Khalil
- Department of Neurology, Medical University of Graz, Graz, Austria
| | | | - Fritz Leutmezer
- Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Thomas Berger
- Clinical Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
| | - Markus Reindl
- Clinical Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria.
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Huang P, Takai Y, Kusano-Arai O, Ramadhanti J, Iwanari H, Miyauchi T, Sakihama T, Han JY, Aoki M, Hamakubo T, Fujihara K, Yasui M, Abe Y. The binding property of a monoclonal antibody against the extracellular domains of aquaporin-4 directs aquaporin-4 toward endocytosis. Biochem Biophys Rep 2016; 7:77-83. [PMID: 28955892 PMCID: PMC5613303 DOI: 10.1016/j.bbrep.2016.05.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 05/13/2016] [Accepted: 05/24/2016] [Indexed: 12/03/2022] Open
Abstract
Neuromyelitis optica (NMO), an autoimmune disease of the central nervous system, is characterized by an autoantibody called NMO-IgG that recognizes the extracellular domains (ECDs) of aquaporin-4 (AQP4). In this study, monoclonal antibodies (mAbs) against the ECDs of mouse AQP4 were established by a baculovirus display method. Two types of mAb were obtained: one (E5415A) recognized both M1 and M23 isoforms, and the other (E5415B) almost exclusively recognized the square-array-formable M23 isoform. While E5415A enhanced endocytosis of both M1 and M23, followed by degradation in cells expressing AQP4, including astrocytes, E5415B did so to a much lesser degree, as determined by live imaging using fluorescence-labeled antibodies and by Western blotting of lysate of cells treated with these mAbs. E5415A promoted cluster formation of AQP4 on the cell surface prior to endocytosis as determined by immunofluorescent microscopic observation of bound mAbs to astrocytes as well as by Blue native PAGE analysis of AQP4 in the cells treated with the mAbs. These observations clearly indicate that an anti-AQP4-ECDs antibody possessing an ability to form a large cluster of AQP4 by cross-linking two or more tetramers outside the AQP4 arrays enhances endocytosis and the subsequent lysosomal degradation of AQP4. Two mAbs against the ECD of mAQP4 with different binding properties was established. One of them, E5415A, bound to mAQP4 independent of OAP-formation of AQP4. E5415A but not E5415B strongly enhanced endocytosis of endogenous AQP4 in astrocytes. E5415A formed large clusters of AQP4 cross-linking multiple AQP4 functional units. It is the cluster formation of AQP4 that triggers AQP4 endocytosis.
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Affiliation(s)
- Ping Huang
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan
| | - Yoshiki Takai
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
| | - Osamu Kusano-Arai
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Julia Ramadhanti
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan
| | - Hiroko Iwanari
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Takayuki Miyauchi
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan.,Keio Advanced Research Center for Water Biology and Medicine, Keio University, Tokyo, Japan
| | - Toshiko Sakihama
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Jing-Yan Han
- Department Integration of Chinese and Western Medicine, Peking University Health Science Center, Beijing, China.,Tasly Microcirculation Research Center, Peking University Health Science Center, Beijing, China.,Key Laboratory of Microcirculation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Beijing, China
| | - Masashi Aoki
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
| | - Takao Hamakubo
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Kazuo Fujihara
- Department of Multiple Sclerosis Therapeutics, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Masato Yasui
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan.,Keio Advanced Research Center for Water Biology and Medicine, Keio University, Tokyo, Japan
| | - Yoichiro Abe
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, Japan.,Keio Advanced Research Center for Water Biology and Medicine, Keio University, Tokyo, Japan
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Development of an Aquaporin-4 Orthogonal Array of Particle-Based ELISA for Neuromyelitis Optica Autoantibodies Detection. PLoS One 2015; 10:e0143679. [PMID: 26599905 PMCID: PMC4658006 DOI: 10.1371/journal.pone.0143679] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 11/09/2015] [Indexed: 12/28/2022] Open
Abstract
Serological markers of Nuromyelitis Optica (NMO), an autoimmune disorder of the central nervous system, are autoantibodies targeting the astrocytic water channel aquaporin-4 (AQP4). We have previously demonstrated that the main epitopes for these autoantibodies (AQP4-IgG) are generated by the supramolecular arrangement of AQP4 tetramers into an Orthogonal Array of Particles (OAPs). Many tests have been developed to detect AQP4-IgG in patient sera but several procedural issues affect OAP assembly and consequently test sensitivity. To date, the protein based ELISA test shows the lowest sensitivity while representing a valid alternative to the more sensitive cell based assay (CBA), which, however, shows economic, technical and interpretation problems. Here we have developed a high perfomance ELISA in which native OAPs are used as the molecular target. To this aim a native size exclusion chromatography method has been developed to isolate integral, highly pure and AQP4-IgG-recognized OAPs from rat brain. These OAPs were immobilized and oriented on a plastic plate by a sandwich approach and 139 human sera were tested, including 67 sera from NMO patients. The OAP-ELISA showed a 99% specificity and a higher sensitivity (91%) compared to the CBA test. A comparative analysis revealed an end-point titer three orders of magnitude higher than the commercial ELISA and six times higher than our in-house CBA test. We show that CNS-extracted OAPs are crucial elements in order to perform an efficient AQP4-IgG test and the OAP-ELISA developed represents a valid alternative to the CBA currently used.
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25
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Miyazaki-Komine K, Takai Y, Huang P, Kusano-Arai O, Iwanari H, Misu T, Koda K, Mitomo K, Sakihama T, Toyama Y, Fujihara K, Hamakubo T, Yasui M, Abe Y. High avidity chimeric monoclonal antibodies against the extracellular domains of human aquaporin-4 competing with the neuromyelitis optica autoantibody, NMO-IgG. Br J Pharmacol 2015; 173:103-14. [PMID: 26398585 DOI: 10.1111/bph.13340] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 09/15/2015] [Accepted: 09/18/2015] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Most of the cases of neuromyelitis optica (NMO) are characterized by the presence of an autoantibody, NMO-IgG, which recognizes the extracellular domains of the water channel, aquaporin-4. Binding of NMO-IgG to aquaporin-4 expressed in end-feet of astrocytes leads to complement-dependent disruption of astrocytes followed by demyelination. One therapeutic option for NMO is to prevent the binding of NMO-IgG to aquaporin-4, using high-avidity, non-pathogenic-chimeric, monoclonal antibodies to this water channel. We describe here the development of such antibodies. EXPERIMENTAL APPROACH cDNAs encoding variable regions of heavy and light chains of monoclonal antibodies against the extracellular domains of human aquaporin-4 were cloned from hybridoma total RNA and fused to those encoding constant regions of human IgG1 and Igκ respectively. Then mammalian expression vectors were constructed to establish stable cell lines secreting mature chimeric antibodies. KEY RESULTS Original monoclonal antibodies showed high avidity binding to human aquaporin-4, as determined by ELISA. Live imaging using Alexa-Fluor-555-labelled antibodies revealed that the antibody D15107 more rapidly bound to cells expressing human aquaporin-4 than others and strongly enhanced endocytosis of this water channel, while D12092 also bound rapidly to human aquaporin-4 but enhanced endocytosis to a lesser degree. Chimeric D15107 prevented complement-dependent cytotoxicity induced by NMO-IgG from patient sera in vitro. CONCLUSIONS AND IMPLICATIONS We have established non-pathogenic, high-avidity, chimeric antibodies against the extracellular domains of human aquaporin-4, which provide a novel therapeutic option for preventing the progress and recurrence of NMO/NMO spectrum disorders.
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Affiliation(s)
- Kaori Miyazaki-Komine
- Department of Pharmacology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.,Department of Orthopaedic Surgery, School of Medicine, Keio University, Tokyo, Japan
| | - Yoshiki Takai
- Department of Neurology, Tohoku University School of Medicine, 1-1 Seiryomachi, Aoba-ku, Sendai, 980-8574, Japan
| | - Ping Huang
- Department of Pharmacology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Osamu Kusano-Arai
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan.,Institute of Immunology Co., Ltd., 1-1-10 Koraku, Bunkyo-ku, Tokyo, 112-0004, Japan
| | - Hiroko Iwanari
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan
| | - Tatsuro Misu
- Department of Multiple Sclerosis Therapeutics, Tohoku University Graduate School of Medicine, 1-1 Seiryomachi, Aoba-ku, Sendai, 980-8574, Japan
| | - Katsushi Koda
- Research and Development Division, Perseus Proteomics Inc., 4-7-6 Komaba, Meguro-ku, Tokyo, 153-0041, Japan
| | - Katsuyuki Mitomo
- Research and Development Division, Perseus Proteomics Inc., 4-7-6 Komaba, Meguro-ku, Tokyo, 153-0041, Japan
| | - Toshiko Sakihama
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan
| | - Yoshiaki Toyama
- Department of Orthopaedic Surgery, School of Medicine, Keio University, Tokyo, Japan
| | - Kazuo Fujihara
- Department of Multiple Sclerosis Therapeutics, Tohoku University Graduate School of Medicine, 1-1 Seiryomachi, Aoba-ku, Sendai, 980-8574, Japan
| | - Takao Hamakubo
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan
| | - Masato Yasui
- Department of Pharmacology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.,Keio Advanced Research Center for Water Biology and Medicine, Keio University, Tokyo, Japan
| | - Yoichiro Abe
- Department of Pharmacology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.,Keio Advanced Research Center for Water Biology and Medicine, Keio University, Tokyo, Japan
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26
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Kashipazha D, Mohammadianinejad SE, Majdinasab N, Azizi M, Jafari M. A descriptive study of prevalence, clinical features and other findings of neuromyelitis optica and neuromyelitis optica spectrum disorder in Khuzestan Province, Iran. IRANIAN JOURNAL OF NEUROLOGY 2015; 14:204-10. [PMID: 26885339 PMCID: PMC4754599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Neuromyelitis optica (NMO) is an uncommon neuro-inflammatory syndrome that has shown to be distinct from multiple sclerosis (MS) and associated with the autoantibody marker NMO-immunoglobulin G (IgG). There are still only a few studies regarding the epidemiology of NMO in Iran. In the present study, we tried to describe the epidemiology of NMO in Khuzestan as one of the densely populated regions in Iran. METHODS A cross-sectional study was performed during the period 2013-2014. Multiple regional sources of data were used including hospital records, details from neurologists and MS society database. The diagnosis of NMO was based on clinical presentation, abnormal findings on neuroimaging and serological tests. RESULTS A 51 Caucasian patients (36 patients with NMO and 15 with NMO-spectrum disorder) were identified with a female/male ratio of 7.5:1.0. The crude prevalence of NMO was 1.1/100,000 population. The mean age at onset was 29.2 ± 6.1 years and the mean duration of symptoms was 5.0 ± 0.4 years. The majority of patients (60.8%) were classified as having mild disability (Expanded Disability Status Scale = 0-3.5). Among of 35 patients whose titer of NMO-IgG was measured, 19 (54.2%) were seropositive. CONCLUSION Our study suggests that NMO prevalence rate in South West Iran (Khuzestan Province) is much lower than that reported for MS prevalence rate (16.2/100,000) and our patients had a lower age at onset presentation and milder course of the disease than western countries.
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Affiliation(s)
- Davood Kashipazha
- 1 Department of Neurology, Golestan Hospital, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | | | - Nastaran Majdinasab
- 1 Department of Neurology, Golestan Hospital, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Mostafa Azizi
- 1 Department of Neurology, Golestan Hospital, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Majid Jafari
- 1 Department of Neurology, Golestan Hospital, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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Specificity and sensitivity of aquaporin 4 antibody detection tests in patients with neuromyelitis optica: A meta-analysis. Mult Scler Relat Disord 2015. [DOI: 10.1016/j.msard.2015.06.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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28
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Kitley J, Woodhall M, Leite MI, Palace J, Vincent A, Waters P. Aquaporin-4 antibody isoform binding specificities do not explain clinical variations in NMO. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2015; 2:e121. [PMID: 26140280 PMCID: PMC4476052 DOI: 10.1212/nxi.0000000000000121] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Accepted: 04/20/2015] [Indexed: 11/15/2022]
Abstract
Objective: To assess the clinical relevance of the differential binding of antibodies against the 2 main aquaporin-4 (AQP4) isoforms in neuromyelitis optica (NMO) patient sera using stably transfected human embryonic kidney cells. Methods: Flow cytometry of human embryonic kidney cells stably transfected with either M23 or M1 AQP4 was used to measure antibody endpoint titers in 52 remission samples and 26 relapse samples from 34 patients with clinically well-characterized AQP4 antibody–positive NMO/NMO spectrum disorder. Results: The AQP4 M23 (40–61,440) and AQP4 M1 (<20–20,480) titers varied widely between patients, as did the M23:M1 antibody ratio (1–192). In 76 of 78 samples, binding to M23 was higher than binding to M1, including during relapses and remissions (p < 0.0001), and the M23:M1 ratio was relatively constant within an individual patient. Titers usually fell after immunosuppression, but the titers at which relapses occurred varied markedly; no threshold level for relapses could be identified, and relapses could occur without a rise in titers. Relapse severity did not correlate with M23 or M1 antibody titers, although there was a correlation between the earliest M23 titers and annualized relapse rates. The M23:M1 ratio and absolute M23 and M1 titers did not relate to age at disease onset, ethnicity, disease severity, phenotype, or relapses at different anatomical sites. Conclusion: Relative AQP4 antibody binding to M23 and M1 isoforms differs between patients but there is no consistent association between these differences and clinical characteristics of disease. Nevertheless, the M23 isoform provided a slightly more sensitive substrate for AQP4-antibody assays, particularly for follow-up studies.
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Affiliation(s)
- Joanna Kitley
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Mark Woodhall
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - M Isabel Leite
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Jackie Palace
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Patrick Waters
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
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Pisani F, Mola MG, Simone L, Rosito S, Alberga D, Mangiatordi GF, Lattanzi G, Nicolotti O, Frigeri A, Svelto M, Nicchia GP. Identification of a point mutation impairing the binding between aquaporin-4 and neuromyelitis optica autoantibodies. J Biol Chem 2014; 289:30578-30589. [PMID: 25239624 DOI: 10.1074/jbc.m114.582221] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Neuromyelitis optica (NMO) is characterized by the presence of pathogenic autoantibodies (NMO-IgGs) against supra-molecular assemblies of aquaporin-4 (AQP4), known as orthogonal array of particles (OAPs). NMO-IgGs have a polyclonal origin and recognize different conformational epitopes involving extracellular AQP4 loops A, C, and E. Here we hypothesize a pivotal role for AQP4 transmembrane regions (TMs) in epitope assembly. On the basis of multialignment analysis, mutagenesis, NMO-IgG binding, and cytotoxicity assay, we have disclosed the key role of aspartate 69 (Asp(69)) of TM2 for NMO-IgG epitope assembly. Mutation of Asp(69) to histidine severely impairs NMO-IgG binding for 85.7% of the NMO patient sera analyzed here. Although Blue Native-PAGE, total internal reflection fluorescence microscopy, and water transport assays indicate that the OAP Asp(69) mutant is similar in structure and function to the wild type, molecular dynamic simulations have revealed that the D(69)H mutation has the effect of altering the structural rearrangements of extracellular loop A. In conclusion, Asp(69) is crucial for the spatial control of loop A, the particular molecular conformation of which enables the assembly of NMO-IgG epitopes. These findings provide additional clues for new strategies for NMO treatment and a wealth of information to better approach NMO pathogenesis.
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Affiliation(s)
- Francesco Pisani
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Center of Excellence in Comparative Genomics, University of Bari "Aldo Moro," 70126 Bari
| | - Maria Grazia Mola
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Center of Excellence in Comparative Genomics, University of Bari "Aldo Moro," 70126 Bari
| | - Laura Simone
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Center of Excellence in Comparative Genomics, University of Bari "Aldo Moro," 70126 Bari
| | - Stefania Rosito
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Center of Excellence in Comparative Genomics, University of Bari "Aldo Moro," 70126 Bari
| | - Domenico Alberga
- Dipartimento Interateneo di Fisica "M. Merlin", INFN and TIRES, Università di Bari "Aldo Moro", via Orabona, 4, 70126 Bari, Italy
| | - Giuseppe Felice Mangiatordi
- Dipartimento di Farmacia-Scienze del Farmaco, Via Orabona, 4, Università di Bari "Aldo Moro", Bari, 70126 Bari, and
| | - Gianluca Lattanzi
- Dipartimento Interateneo di Fisica "M. Merlin", INFN and TIRES, Università di Bari "Aldo Moro", via Orabona, 4, 70126 Bari, Italy
| | - Orazio Nicolotti
- Dipartimento di Farmacia-Scienze del Farmaco, Via Orabona, 4, Università di Bari "Aldo Moro", Bari, 70126 Bari, and
| | - Antonio Frigeri
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Center of Excellence in Comparative Genomics, University of Bari "Aldo Moro," 70126 Bari
| | - Maria Svelto
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Center of Excellence in Comparative Genomics, University of Bari "Aldo Moro," 70126 Bari
| | - Grazia Paola Nicchia
- Department of Bioscience, Biotechnologies and Biopharmaceutics and Center of Excellence in Comparative Genomics, University of Bari "Aldo Moro," 70126 Bari,.
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30
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Jarius S, Paul F, Fechner K, Ruprecht K, Kleiter I, Franciotta D, Ringelstein M, Pache F, Aktas O, Wildemann B. Aquaporin-4 antibody testing: direct comparison of M1-AQP4-DNA-transfected cells with leaky scanning versus M23-AQP4-DNA-transfected cells as antigenic substrate. J Neuroinflammation 2014; 11:129. [PMID: 25074611 PMCID: PMC4128531 DOI: 10.1186/1742-2094-11-129] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 07/08/2014] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Neuromyelitis optica (NMO, Devic syndrome) is associated with antibodies to aquaporin-4 (NMO-IgG/AQP4-Ab) in the majority of cases. NMO-IgG/AQP4-Ab seropositivity in patients with NMO and its spectrum disorders has important differential diagnostic, prognostic and therapeutic implications. So-called cell-based assays (CBA) are thought to provide the best AQP4-Ab detection rates. OBJECTIVE To compare directly the AQP4-IgG detection rates of the currently most widely used commercial CBA, which employs cells transfected with a full-length (M1)-human AQP4 DNA in a fashion that allows leaky scanning (LS) and thus expression of M23-AQP4 in addition to M1-AQP, to that of a newly developed CBA from the same manufacturer employing cells transfected with human M23-AQP4-DNA. METHODS Results from 368 serum samples that had been referred for routine AQP4-IgG determination and had been tested in parallel in the two assays were compared. RESULTS Seventy-seven out of 368 samples (20.9%) were positive for NMO-IgG/AQP4-Ab in at least one assay. Of these, 73 (94.8%) were positive in both assays. A single sample (1.3%) was exclusively positive in the novel assay; three samples (3.9%) were unequivocally positive only in the 'classic' assay due to high background intensity in the novel assay. Both median fluorescence intensity and background intensity were higher in the new assay. CONCLUSIONS This large study did not reveal significant differences in AQP4-IgG detection rates between the 'classic' CBA and a new M23-DNA-based CBA. Importantly, our results largely re-affirm the validity of previous studies that had used the 'classic' AQP4-CBA to establish NMO-IgG/AQP4-Ab seropositivity rates in NMO and in a variety of NMO spectrum disorders.
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Affiliation(s)
- Sven Jarius
- Molecular Neuroimmunology, Department of Neurology, University of Heidelberg, Heidelberg, Germany.
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31
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Abstract
Aquaporins (AQPs) are a family of membrane water channels that basically function as regulators of intracellular and intercellular water flow. To date, thirteen aquaporins have been characterized. They are distributed wildly in specific cell types in multiple organs and tissues. Each AQP channel consists of six membrane-spanning alpha-helices that have a central water-transporting pore. Four AQP monomers assemble to form tetramers, which are the functional units in the membrane. Some of AQPs also transport urea, glycerol, ammonia, hydrogen peroxide, and gas molecules. AQP-mediated osmotic water transport across epithelial plasma membranes facilitates transcellular fluid transport and thus water reabsorption. AQP-mediated urea and glycerol transport is involved in energy metabolism and epidermal hydration. AQP-mediated CO2 and NH3 transport across membrane maintains intracellular acid-base homeostasis. AQPs are also involved in the pathophysiology of a wide range of human diseases (including water disbalance in kidney and brain, neuroinflammatory disease, obesity, and cancer). Further work is required to determine whether aquaporins are viable therapeutic targets or reliable diagnostic and prognostic biomarkers.
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