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Casey A, Fiorino EK, Wambach J. Innovations in Childhood Interstitial and Diffuse Lung Disease. Clin Chest Med 2024; 45:695-715. [PMID: 39069332 DOI: 10.1016/j.ccm.2024.04.002] [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: 07/30/2024]
Abstract
Children's interstitial and diffuse lung diseases (chILDs) are a heterogenous and diverse group of lung disorders presenting during childhood. Infants and children with chILD disorders present with respiratory signs and symptoms as well as diffuse lung imaging abnormalities. ChILD disorders are associated with significant health care resource utilization and high morbidity and mortality. The care of patients with chILD has been improved through multidisciplinary care, multicenter collaboration, and the establishment of patient research networks in the United Stated and abroad. This review details past and current innovations in the diagnosis and clinical care of children with chILD.
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Affiliation(s)
- Alicia Casey
- Department of Pediatrics, Division of Pulmonary Medicine, Harvard Medical School, Boston Children's Hospital, Boston, MA 02115, USA.
| | - Elizabeth K Fiorino
- Department of Science Education and Pediatrics, Donald and Barabara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Jennifer Wambach
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, MO 63110, USA
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2
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Yang X, Forstner ME, Rothenaigner I, Bullo M, Şismanlar TE, Aslan AT, Latzin P, Hadian K, Griese M. Cyclosporine A in children with ABCA3 deficiency. Pediatr Pulmonol 2024. [PMID: 39041931 DOI: 10.1002/ppul.27178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 06/23/2024] [Accepted: 07/03/2024] [Indexed: 07/24/2024]
Abstract
BACKGROUND Biallelic ATP-binding cassette subfamily A member 3 (ABCA3) variants can cause interstitial lung disease in children and adults, for which no proven treatments exist. Recent in vitro evidence suggested that cyclosporine A (CsA) could correct some ABCA3 variants, however for other variants this is unknown and no data in patients exist. METHODS We retrieved the clinical data of two children aged 2 and 4 years carrying homozygous ABCA3 variants (G210C and Q1045R, respectively) and empiric CsA treatment from the Kids Lung Register database. In vitro experiments functionally characterized the two variants and explored the effects of CsA alone or combined with hydroxychloroquine (HCQ) in a human alveolar epithelial cell line (A549) derived from adenocarcinoma cells. RESULTS Six weeks following the introduction of CsA, both children required a reduced O2 flow supply, which then remained stable on CsA. Later, when CsA was discontinued, the clinical status of the children remained unchanged. Of note, the children simultaneously received prednisolone, azithromycin, and HCQ. In vitro, both ABCA3 variants demonstrated defective lysosomal colocalization and impaired ABCA3+ vesicle size, with proteolytic cleavage impairment only in Q1045R. CsA alone corrected the trafficking impairment and ABCA3+ vesicle size of both variants with a variant-specific effect on phosphatidylcholine recycling in G210C. CsA combined with HCQ were additive for improving trafficking of ABCA3 in G210C, but not in Q1045R. CONCLUSIONS CsA treatment might be helpful for certain patients with ABCA3 deficiency, however, currently strong clinical supporting evidence is lacking. Appropriate trials are necessary to overcome this unmet need.
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Affiliation(s)
- Xiaohua Yang
- Dr. von Haunersches Kinderspital, University of Munich, German Center for Lung Research (DZL), Munich, Germany
| | - Maria E Forstner
- Dr. von Haunersches Kinderspital, University of Munich, German Center for Lung Research (DZL), Munich, Germany
| | - Ina Rothenaigner
- Research Unit Signaling and Translation, Helmholtz Zentrum München, Neuherberg, Germany
| | - Marina Bullo
- Pediatric Pneumology and Allergology, University Children´s Inselspital Bern, University of Bern, Bern, Switzerland
| | - Tugba E Şismanlar
- Department of Pediatric Pulmonology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Ayse T Aslan
- Department of Pediatric Pulmonology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Philipp Latzin
- Pediatric Pneumology and Allergology, University Children´s Inselspital Bern, University of Bern, Bern, Switzerland
| | - Kamyar Hadian
- Research Unit Signaling and Translation, Helmholtz Zentrum München, Neuherberg, Germany
| | - Matthias Griese
- Dr. von Haunersches Kinderspital, University of Munich, German Center for Lung Research (DZL), Munich, Germany
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3
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Giunta-Stibb H, Hackett B. Interstitial lung disease in the newborn. J Perinatol 2024:10.1038/s41372-024-02036-9. [PMID: 38956315 DOI: 10.1038/s41372-024-02036-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 05/30/2024] [Accepted: 06/18/2024] [Indexed: 07/04/2024]
Abstract
Although relatively rare, interstitial lung diseases may present with respiratory distress in the newborn period. Most commonly these include developmental and growth disorders, disorders of surfactant synthesis and homeostasis, pulmonary interstitial glycogenosis, and neuroendocrine cell hyperplasia of infancy. Although the diagnosis of these disorders is sometimes made based on clinical presentation and imaging, due to the significant overlap between disorders and phenotypic variability, lung biopsy or, increasingly genetic testing is needed for diagnosis. These diseases may result in significant morbidity and mortality. Effective medical treatment options are in some cases limited and/or invasive. The genetic basis for some of these disorders has been identified, and with increased utilization of exome and whole genome sequencing even before lung biopsy, further insights into their genetic etiologies should become available.
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Affiliation(s)
- Hannah Giunta-Stibb
- Divisions of Neonatology and Pulmonology, Department of Pediatrics, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA.
| | - Brian Hackett
- Mildred Stahlman Division of Neonatology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
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4
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Bush A. Learning from cystic fibrosis: How can we start to personalise treatment of Children's Interstitial Lung Disease (chILD)? Paediatr Respir Rev 2024; 50:46-53. [PMID: 37996258 DOI: 10.1016/j.prrv.2023.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 11/17/2023] [Indexed: 11/25/2023]
Abstract
Cystic fibrosis (CF) is a monogenic disorder cause by mutations in the CF Transmembrane Regulator (CFTR) gene. The prognosis of cystic fibrosis has been transformed by the discovery of highly effective modulator therapies (HEMT). Treatment has changed from reactive therapy dealing with complications of the disease to pro-active correction of the underlying molecular functional abnormality. This has come about by discovering the detailed biology of the different CF molecular sub-endotypes; the development of biomarkers to assess response even in mild disease or young children; the performance of definitive large randomised controlled trials in patients with a common mutation and the development of in vitro testing systems to test efficacy in those patients with rare CFTR mutations. As a result, CF is now an umbrella term, rather than a specific diagnostic label; we have moved from clinical phenotypes to molecular subendotypes. Children's Interstitial Lung Diseases (chILDs) comprise more than 200 entities, and are a diverse group of diseases, for an increasing number of which an underlying gene mutation has been discovered. Many of these entities are umbrella terms, such as pulmonary alveolar proteinosis or hypersensitivity pneumonitis, for each of which there are multiple and very different endotypes. Even those chILDs for which a specific gene mutation has been discovered comprise, as with CF, different molecular subendotypes likely mandating different therapies. For most chILDs, current treatment is non-specific (corticosteroids, azithromycin, hydroxychloroquine). The variability of the different entities means that there is little evidence for the efficacy of any treatment. This review considers how some of the lessons of the success story of CF are being applied to chILD, thus opening the opportunities for truly personalised medicine in these conditions. Advances in knowledge in the molecular biology of surfactant protein C and Adenosine triphosphate binding cassette subfamily A member 3 (ABCA3), and the possibilities of discovering novel therapies by in vitro studies will especially be highlighted.
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Affiliation(s)
- Andrew Bush
- National Heart and Lung Institute, Imperial College, and Imperial Centre for Paediatrics and Child Health, Consultant Paediatric Chest Physician, Royal Brompton Hospital, UK.
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5
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Veit G, Matsuo M, Okiyoneda T. Editorial: Advancing therapeutic strategies: exploring ABC transporters and chemicals affecting their expression and function for disease treatment. Front Pharmacol 2024; 15:1423979. [PMID: 38803436 PMCID: PMC11128889 DOI: 10.3389/fphar.2024.1423979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Accepted: 05/07/2024] [Indexed: 05/29/2024] Open
Affiliation(s)
- Guido Veit
- Department of Physiology, McGill University, Montréal, QC, Canada
| | - Michinori Matsuo
- Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women’s University, Kyoto, Japan
| | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
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6
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Piccolo D, Zarouchlioti C, Bellingham J, Guarascio R, Ziaka K, Molday RS, Cheetham ME. A Proximity Complementation Assay to Identify Small Molecules That Enhance the Traffic of ABCA4 Misfolding Variants. Int J Mol Sci 2024; 25:4521. [PMID: 38674104 PMCID: PMC11050442 DOI: 10.3390/ijms25084521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/16/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024] Open
Abstract
ABCA4-related retinopathy is the most common inherited Mendelian eye disorder worldwide, caused by biallelic variants in the ATP-binding cassette transporter ABCA4. To date, over 2200 ABCA4 variants have been identified, including missense, nonsense, indels, splice site and deep intronic defects. Notably, more than 60% are missense variants that can lead to protein misfolding, mistrafficking and degradation. Currently no approved therapies target ABCA4. In this study, we demonstrate that ABCA4 misfolding variants are temperature-sensitive and reduced temperature growth (30 °C) improves their traffic to the plasma membrane, suggesting the folding of these variants could be rescuable. Consequently, an in vitro platform was developed for the rapid and robust detection of ABCA4 traffic to the plasma membrane in transiently transfected cells. The system was used to assess selected candidate small molecules that were reported to improve the folding or traffic of other ABC transporters. Two candidates, 4-PBA and AICAR, were identified and validated for their ability to enhance both wild-type ABCA4 and variant trafficking to the cell surface in cell culture. We envision that this platform could serve as a primary screen for more sophisticated in vitro testing, enabling the discovery of breakthrough agents to rescue ABCA4 protein defects and mitigate ABCA4-related retinopathy.
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Affiliation(s)
- Davide Piccolo
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Christina Zarouchlioti
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - James Bellingham
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Rosellina Guarascio
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Kalliopi Ziaka
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
| | - Robert S. Molday
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada;
| | - Michael E. Cheetham
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (D.P.); (C.Z.); (R.G.); (K.Z.)
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7
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Sun YL, Hennessey EE, Heins H, Yang P, Villacorta-Martin C, Kwan J, Gopalan K, James M, Emili A, Cole FS, Wambach JA, Kotton DN. Human pluripotent stem cell modeling of alveolar type 2 cell dysfunction caused by ABCA3 mutations. J Clin Invest 2024; 134:e164274. [PMID: 38226623 PMCID: PMC10786693 DOI: 10.1172/jci164274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 11/14/2023] [Indexed: 01/17/2024] Open
Abstract
Mutations in ATP-binding cassette A3 (ABCA3), a phospholipid transporter critical for surfactant homeostasis in pulmonary alveolar type II epithelial cells (AEC2s), are the most common genetic causes of childhood interstitial lung disease (chILD). Treatments for patients with pathological variants of ABCA3 mutations are limited, in part due to a lack of understanding of disease pathogenesis resulting from an inability to access primary AEC2s from affected children. Here, we report the generation of AEC2s from affected patient induced pluripotent stem cells (iPSCs) carrying homozygous versions of multiple ABCA3 mutations. We generated syngeneic CRISPR/Cas9 gene-corrected and uncorrected iPSCs and ABCA3-mutant knockin ABCA3:GFP fusion reporter lines for in vitro disease modeling. We observed an expected decreased capacity for surfactant secretion in ABCA3-mutant iPSC-derived AEC2s (iAEC2s), but we also found an unexpected epithelial-intrinsic aberrant phenotype in mutant iAEC2s, presenting as diminished progenitor potential, increased NFκB signaling, and the production of pro-inflammatory cytokines. The ABCA3:GFP fusion reporter permitted mutant-specific, quantifiable characterization of lamellar body size and ABCA3 protein trafficking, functional features that are perturbed depending on ABCA3 mutation type. Our disease model provides a platform for understanding ABCA3 mutation-mediated mechanisms of alveolar epithelial cell dysfunction that may trigger chILD pathogenesis.
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Affiliation(s)
- Yuliang L. Sun
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, Massachusetts, USA
- The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Erin E. Hennessey
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, Massachusetts, USA
- The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Hillary Heins
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine and St. Louis Children’s Hospital, St. Louis, Missouri, USA
| | - Ping Yang
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine and St. Louis Children’s Hospital, St. Louis, Missouri, USA
| | - Carlos Villacorta-Martin
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, Massachusetts, USA
| | - Julian Kwan
- Departments of Biology and Biochemistry, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Krithi Gopalan
- University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Marianne James
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, Massachusetts, USA
| | - Andrew Emili
- Departments of Biology and Biochemistry, Boston University School of Medicine, Boston, Massachusetts, USA
| | - F. Sessions Cole
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine and St. Louis Children’s Hospital, St. Louis, Missouri, USA
| | - Jennifer A. Wambach
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine and St. Louis Children’s Hospital, St. Louis, Missouri, USA
| | - Darrell N. Kotton
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, Massachusetts, USA
- The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
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8
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Bernardinello N, Griese M, Borie R, Spagnolo P. Emerging Treatments for Childhood Interstitial Lung Disease. Paediatr Drugs 2024; 26:19-30. [PMID: 37948041 PMCID: PMC10770003 DOI: 10.1007/s40272-023-00603-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/17/2023] [Indexed: 11/12/2023]
Abstract
Childhood interstitial lung disease (chILD) is a large and heterogeneous group of disorders characterized by diffuse lung parenchymal markings on chest imaging and clinical signs such as dyspnea and hypoxemia from functional impairment. While some children already present in the neonatal period with interstitial lung disease (ILD), others develop ILD during their childhood and adolescence. A timely and accurate diagnosis is essential to gauge treatment and improve prognosis. Supportive care can reduce symptoms and positively influence patients' quality of life; however, there is no cure for many of the chILDs. Current therapeutic options include anti-inflammatory or immunosuppressive drugs. Due to the rarity of the conditions and paucity of research in this field, most treatments are empirical and based on case series, and less than a handful of small, randomized trials have been conducted thus far. A trial on hydroxychloroquine yielded good safety but a much smaller effect size than anticipated. A trial in fibrotic disease with the multitargeted tyrosine kinase inhibitor nintedanib showed similar pharmacokinetics and safety as in adults. The unmet need for the treatment of chILDs remains high. This article summarizes current treatments and explores potential therapeutic options for patients suffering from chILD.
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Affiliation(s)
- Nicol Bernardinello
- Respiratory Disease Unit, Department of Cardiac Thoracic, Vascular Sciences and Public Health, University of Padova, Via N. Giustiniani n°2, 35128, Padua, Italy
| | - Matthias Griese
- Department of Pediatric Pneumology, Dr. von Hauner Children's Hospital, German Center for Lung Research (DZL), Ludwig-Maximilians University, Munich, Germany
| | - Raphaël Borie
- Université de Paris, INSERM UMR 1152, Service de Pneumologie A, Centre de compétences maladies pulmonaires rares, Hôpital Bichat-Claude Bernard, AP-HP, 75018, Paris, France
| | - Paolo Spagnolo
- Respiratory Disease Unit, Department of Cardiac Thoracic, Vascular Sciences and Public Health, University of Padova, Via N. Giustiniani n°2, 35128, Padua, Italy.
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9
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Peers de Nieuwburgh M, Wambach JA, Griese M, Danhaive O. Towards personalized therapies for genetic disorders of surfactant dysfunction. Semin Fetal Neonatal Med 2023; 28:101500. [PMID: 38036307 PMCID: PMC10753445 DOI: 10.1016/j.siny.2023.101500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
Genetic disorders of surfactant dysfunction are a rare cause of chronic, progressive or refractory respiratory failure in term and preterm infants. This review explores genetic mechanisms underpinning surfactant dysfunction, highlighting specific surfactant-associated genes including SFTPB, SFTPC, ABCA3, and NKX2.1. Pathogenic variants in these genes contribute to a range of clinical presentations and courses, from neonatal hypoxemic respiratory failure to childhood interstitial lung disease and even adult-onset pulmonary fibrosis. This review emphasizes the importance of early recognition, thorough phenotype assessment, and assessment of variant functionality as essential prerequisites for treatments including lung transplantation. We explore emerging treatment options, including personalized pharmacological approaches and gene therapy strategies. In conclusion, this comprehensive review offers valuable insights into the pathogenic mechanisms of genetic disorders of surfactant dysfunction, genetic fundamentals, available and emerging therapeutic options, and underscores the need for further research to develop personalized therapies for affected infants and children.
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Affiliation(s)
- Maureen Peers de Nieuwburgh
- Division of Neonatology, Department of Pediatrics, St-Luc University Hospital, Catholic University of Louvain, Brussels, Belgium.
| | - Jennifer A Wambach
- Washington University School of Medicine/St. Louis Children's Hospital, One Children's Place, St. Louis, Missouri, USA.
| | - Matthias Griese
- Pediatric Pulmonology, Dr von Hauner Children's Hospital, University-Hospital, German Center for Lung Research (DZL), Munich, Germany.
| | - Olivier Danhaive
- Division of Neonatology, Department of Pediatrics, St-Luc University Hospital, Catholic University of Louvain, Brussels, Belgium; Division of Neonatology, Benioff Children's Hospital, University of California San Francisco, San Francisco, CA, USA.
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10
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Ribaudo G, Carotti M, Ongaro A, Oselladore E, Scano M, Zagotto G, Sandonà D, Gianoncelli A. Synthesis and Evaluation of Bithiazole Derivatives As Potential α-Sarcoglycan Correctors. ACS Med Chem Lett 2023; 14:1049-1053. [PMID: 37583821 PMCID: PMC10424318 DOI: 10.1021/acsmedchemlett.3c00046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 07/26/2023] [Indexed: 08/17/2023] Open
Abstract
4'-Methyl-4,5'-bithiazoles were previously identified as cystic fibrosis transmembrane regulator (CFTR) correctors, thus being able to correct folding defective mutants of the channel regulating chloride transport through the membrane. Additionally, bithiazole derivative C17 was reported to recover α-sarcoglycan in vitro and in vivo. We report here the synthesis of two new derivatives of C17, in which the two sides of the bithiazole scaffold were modified. The synthesized compounds and the corresponding precursors were tested in myogenic cells to evaluate the expression of α-sarcoglycan. The results highlighted that both substitutions of the bithiazole scaffold are important to achieve the maximum recovery of the α-sarcoglycan mutant. Nonetheless, partial preservation of the activity was observed. Accordingly, this paves the way to further derivatizations/optimization and target fishing studies, which were preliminarily performed in this study as a proof of concept, allowing the investigation of the molecular mechanisms leading to the α-sarcoglycan correction.
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Affiliation(s)
- Giovanni Ribaudo
- Department
of Molecular and Translational Medicine, University of Brescia, viale Europa 11, 25121 Brescia, Italy
| | - Marcello Carotti
- Department
of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Alberto Ongaro
- Department
of Pharmaceutical and Pharmacological Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy
| | - Erika Oselladore
- Department
of Molecular and Translational Medicine, University of Brescia, viale Europa 11, 25121 Brescia, Italy
| | - Martina Scano
- Department
of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Giuseppe Zagotto
- Department
of Pharmaceutical and Pharmacological Sciences, University of Padova, via Marzolo 5, 35131 Padova, Italy
| | - Dorianna Sandonà
- Department
of Biomedical Sciences, University of Padova, via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Alessandra Gianoncelli
- Department
of Molecular and Translational Medicine, University of Brescia, viale Europa 11, 25121 Brescia, Italy
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11
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Yang X, Forstner M, Rapp CK, Rothenaigner I, Li Y, Hadian K, Griese M. ABCA3 Deficiency-Variant-Specific Response to Hydroxychloroquine. Int J Mol Sci 2023; 24:ijms24098179. [PMID: 37175887 PMCID: PMC10179277 DOI: 10.3390/ijms24098179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/01/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023] Open
Abstract
Biallelic variants in ABCA3, the gene encoding the lipid transporter ATP-binding cassette subfamily A member 3 (ABCA3) that is predominantly expressed in alveolar type II cells, may cause interstitial lung diseases in children (chILD) and adults. Currently, there is no proven therapy, but, frequently, hydroxychloroquine (HCQ) is used empirically. We hypothesized that the in vitro responsiveness to HCQ might correlate to patients' clinical outcomes from receiving HCQ therapy. The clinical data of the subjects with chILD due to ABCA3 deficiency and treated with HCQ were retrieved from the literature and the Kids Lung Register data base. The in vitro experiments were conducted on wild type (WT) and 16 mutant ABCA3-HA-transfected A549 cells. The responses of the functional read out were assessed as the extent of deviation from the untreated WT. With HCQ treatment, 19 patients had improved or unchanged respiratory conditions, and 20 had respiratory deteriorations, 5 of whom transiently improved then deteriorated. The in vitro ABCA3 functional assays identified two variants with complete response, five with partial response, and nine with no response to HCQ. The variant-specific HCQ effects in vivo closely correlated to the in vitro data. An ABCA3+ vesicle volume above 60% of the WT volume was linked to responsiveness to HCQ; the HCQ treatment response was concentration dependent and differed for variants in vitro. We generated evidence for an ABCA3 variant-dependent impact of the HCQ in vitro. This may also apply for HCQ treatment in vivo, as supported by the retrospective and uncontrolled data from the treatment of chILD due to ABCA3 deficiency.
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Affiliation(s)
- Xiaohua Yang
- Dr. von Haunersches Kinderspital, German Center for Lung Research, University of Munich, Lindwurmstr. 4a, 80337 Munich, Germany
| | - Maria Forstner
- Dr. von Haunersches Kinderspital, German Center for Lung Research, University of Munich, Lindwurmstr. 4a, 80337 Munich, Germany
| | - Christina K Rapp
- Dr. von Haunersches Kinderspital, German Center for Lung Research, University of Munich, Lindwurmstr. 4a, 80337 Munich, Germany
| | - Ina Rothenaigner
- Research Unit Signaling and Translation, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Yang Li
- Dr. von Haunersches Kinderspital, German Center for Lung Research, University of Munich, Lindwurmstr. 4a, 80337 Munich, Germany
- Medical College, Chongqing University, Chongqing 400044, China
| | - Kamyar Hadian
- Research Unit Signaling and Translation, Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Matthias Griese
- Dr. von Haunersches Kinderspital, German Center for Lung Research, University of Munich, Lindwurmstr. 4a, 80337 Munich, Germany
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12
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Yang X, Rapp CK, Li Y, Forstner M, Griese M. Quantifying Functional Impairment of ABCA3 Variants Associated with Interstitial Lung Disease. Int J Mol Sci 2023; 24:ijms24087554. [PMID: 37108718 PMCID: PMC10141231 DOI: 10.3390/ijms24087554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
ATP-binding cassette subfamily A member 3 (ABCA3) is a lipid transporter within alveolar type II cells. Patients with bi-allelic variants in ABCA3 may suffer from a variable severity of interstitial lung disease. We characterized and quantified ABCA3 variants' overall lipid transport function by assessing the in vitro impairment of its intracellular trafficking and pumping activity. We expressed the results relative to the wild type, integrated the quantitative readouts from eight different assays and used newly generated data combined with previous results to correlate the variants' function and clinical phenotype. We differentiated normal (within 1 normalized standard deviation (nSD) of the wild-type mean), impaired (within 1 to 3 nSD) and defective (beyond 3 nSD) variants. The transport of phosphatidylcholine from the recycling pathway into ABCA3+ vesicles proved sensitive to the variants' dysfunction. The sum of the quantitated trafficking and pumping predicted a clinical outcome. More than an approximately 50% loss of function was associated with considerable morbidity and mortality. The in vitro quantification of ABCA3 function enables detailed variant characterization, substantially improves the phenotype prediction of genetic variants and possibly supports future treatment decisions.
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Affiliation(s)
- Xiaohua Yang
- Dr. von Haunersches Kinderspital, German Center for Lung Research (DZL), University of Munich, Lindwurmstr. 4a, D-80337 Munich, Germany
| | - Christina K Rapp
- Dr. von Haunersches Kinderspital, German Center for Lung Research (DZL), University of Munich, Lindwurmstr. 4a, D-80337 Munich, Germany
| | - Yang Li
- Dr. von Haunersches Kinderspital, German Center for Lung Research (DZL), University of Munich, Lindwurmstr. 4a, D-80337 Munich, Germany
- Medical College, Chongqing University, Chongqing 400030, China
| | - Maria Forstner
- Dr. von Haunersches Kinderspital, German Center for Lung Research (DZL), University of Munich, Lindwurmstr. 4a, D-80337 Munich, Germany
| | - Matthias Griese
- Dr. von Haunersches Kinderspital, German Center for Lung Research (DZL), University of Munich, Lindwurmstr. 4a, D-80337 Munich, Germany
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13
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Papiris SA, Kannengiesser C, Borie R, Kolilekas L, Kallieri M, Apollonatou V, Ba I, Nathan N, Bush A, Griese M, Dieude P, Crestani B, Manali ED. Genetics in Idiopathic Pulmonary Fibrosis: A Clinical Perspective. Diagnostics (Basel) 2022; 12:2928. [PMID: 36552935 PMCID: PMC9777433 DOI: 10.3390/diagnostics12122928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Unraveling the genetic background in a significant proportion of patients with both sporadic and familial IPF provided new insights into the pathogenic pathways of pulmonary fibrosis. AIM The aim of the present study is to overview the clinical significance of genetics in IPF. PERSPECTIVE It is fascinating to realize the so-far underestimated but dynamically increasing impact that genetics has on aspects related to the pathophysiology, accurate and early diagnosis, and treatment and prevention of this devastating disease. Genetics in IPF have contributed as no other in unchaining the disease from the dogma of a "a sporadic entity of the elderly, limited to the lungs" and allowed all scientists, but mostly clinicians, all over the world to consider its many aspects and "faces" in all age groups, including its co-existence with several extra pulmonary conditions from cutaneous albinism to bone-marrow and liver failure. CONCLUSION By providing additional evidence for unsuspected characteristics such as immunodeficiency, impaired mucus, and surfactant and telomere maintenance that very often co-exist through the interaction of common and rare genetic variants in the same patient, genetics have created a generous and pluralistic yet unifying platform that could lead to the understanding of the injurious and pro-fibrotic effects of many seemingly unrelated extrinsic and intrinsic offending factors. The same platform constantly instructs us about our limitations as well as about the heritability, the knowledge and the wisdom that is still missing.
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Affiliation(s)
- Spyros A. Papiris
- 2nd Pulmonary Medicine Department, General University Hospital “Attikon”, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
| | - Caroline Kannengiesser
- Département de Génétique, APHP Hôpital Bichat, Université de Paris, 75018 Paris, France
- INSERM UMR 1152, Université de Paris, 75018 Paris, France
| | - Raphael Borie
- Service de Pneumologie A, INSERM UMR_1152, Centre de Référence des Maladies Pulmonaires Rares, FHU APOLLO, APHP Hôpital Bichat, Sorbonne Université, 75018 Paris, France
| | - Lykourgos Kolilekas
- 7th Pulmonary Department, Athens Chest Hospital “Sotiria”, 11527 Athens, Greece
| | - Maria Kallieri
- 2nd Pulmonary Medicine Department, General University Hospital “Attikon”, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
| | - Vasiliki Apollonatou
- 2nd Pulmonary Medicine Department, General University Hospital “Attikon”, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
| | - Ibrahima Ba
- Département de Génétique, APHP Hôpital Bichat, Université de Paris, 75018 Paris, France
| | - Nadia Nathan
- Peditric Pulmonology Department and Reference Centre for Rare Lung Diseases RespiRare, INSERM UMR_S933 Laboratory of Childhood Genetic Diseases, Armand Trousseau Hospital, Sorbonne University and APHP, 75012 Paris, France
| | - Andrew Bush
- Paediatrics and Paediatric Respirology, Imperial College, Imperial Centre for Paediatrics and Child Health, Royal Brompton Harefield NHS Foundation Trust, London SW3 6NP, UK
| | - Matthias Griese
- Department of Pediatric Pneumology, Dr von Hauner Children’s Hospital, Ludwig-Maximilians-University, German Center for Lung Research, 80337 Munich, Germany
| | - Philippe Dieude
- Department of Rheumatology, INSERM U1152, APHP Hôpital Bichat-Claude Bernard, Université de Paris, 75018 Paris, France
| | - Bruno Crestani
- Service de Pneumologie A, INSERM UMR_1152, Centre de Référence des Maladies Pulmonaires Rares, FHU APOLLO, APHP Hôpital Bichat, Sorbonne Université, 75018 Paris, France
| | - Effrosyni D. Manali
- 2nd Pulmonary Medicine Department, General University Hospital “Attikon”, Medical School, National and Kapodistrian University of Athens, 12462 Athens, Greece
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14
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TMAO to the rescue of pathogenic protein variants. Biochim Biophys Acta Gen Subj 2022; 1866:130214. [PMID: 35902028 DOI: 10.1016/j.bbagen.2022.130214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 07/11/2022] [Accepted: 07/21/2022] [Indexed: 11/22/2022]
Abstract
Trimethylamine N-oxide (TMAO) is a chemical chaperone found in various organisms including humans. Various studies unveiled that it is an excellent protein-stabilizing agent, and induces folding of unstructured proteins. It is also well established that it can counteract the deleterious effects of urea, salt, and hydrostatic pressure on macromolecular integrity. There is also existence of large body of data regarding its ability to restore functional deficiency of various mutant proteins or pathogenic variants by correcting misfolding defects and inhibiting the formation of high-order toxic protein oligomers. Since an important class of human disease called "protein conformational disorders" is due to protein misfolding and/or formation of high-order oligomers, TMAO stands as a promising molecule for the therapeutic intervention of such diseases. The present review has been designed to gather a comprehensive knowledge of the TMAO's effect on the functional restoration of various mutants, identify its shortcomings and explore its potentiality as a lead molecule. Future prospects have also been suitably incorporated.
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15
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Griese M, Kappler M, Stehling F, Schulze J, Baden W, Koerner-Rettberg C, Carlens J, Prenzel F, Nährlich L, Thalmeier A, Sebah D, Kronfeld K, Rock H, Ruckes C, Wetzke M, Seidl E, Schwerk N, Gebhardt J, Mehl A, Lau SG, Philipp U, Kopp M, Stichtenoth G, Sommerburg O, Stahl M, Kitz R, Rietschel C, Stock P, Ahrens F, Hebestreit H, Segerer F, Brinkmann F, Anne S, Eismann C, Neuner D, Witt S, Hengst M, Feilcke M, Babl J, Stauffer G, Nickolay T, Gorbulev S, Anthony G, Stöhr L, Vieweg L, Strenge-Hesse A, Wetzke M, Seidl E, Schwerk N. Randomized controlled phase 2 trial of hydroxychloroquine in childhood interstitial lung disease. Orphanet J Rare Dis 2022; 17:289. [PMID: 35871071 PMCID: PMC9308121 DOI: 10.1186/s13023-022-02399-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 06/11/2022] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND No results of controlled trials are available for any of the few treatments offered to children with interstitial lung diseases (chILD). We evaluated hydroxychloroquine (HCQ) in a phase 2, prospective, multicentre, 1:1-randomized, double-blind, placebo-controlled, parallel-group/crossover trial. HCQ (START arm) or placebo were given for 4 weeks. Then all subjects received HCQ for another 4 weeks. In the STOP arm subjects already taking HCQ were randomized to 12 weeks of HCQ or placebo (= withdrawal of HCQ). Then all subjects stopped treatment and were observed for another 12 weeks. RESULTS 26 subjects were included in the START arm, 9 in the STOP arm, of these four subjects participated in both arms. The primary endpoint, presence or absence of a response to treatment, assessed as oxygenation (calculated from a change in transcutaneous O2-saturation of ≥ 5%, respiratory rate ≥ 20% or level of respiratory support), did not differ between placebo and HCQ groups. Secondary endpoints including change of O2-saturation ≥ 3%, health related quality of life, pulmonary function and 6-min-walk-test distance, were not different between groups. Finally combining all placebo and all HCQ treatment periods did not identify significant treatment effects. Overall effect sizes were small. HCQ was well tolerated, adverse events were not different between placebo and HCQ. CONCLUSIONS Acknowledging important shortcomings of the study, including a small study population, the treatment duration, lack of outcomes like lung function testing below age of 6 years, the small effect size of HCQ treatment observed requires careful reassessments of prescriptions in everyday practice (EudraCT-Nr.: 2013-003714-40, www.clinicaltrialsregister.eu , registered 02.07.2013). Registration The study was registered on 2 July 2013 (Eudra-CT Number: 2013-003714-40), whereas the approval by BfArM was received 24.11.2014, followed by the approval by the lead EC of the University Hospital Munich on 20.01.2015. At clinicaltrials.gov the trial was additionally registered on November 8, 2015 (NCT02615938).
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Affiliation(s)
- Matthias Griese
- grid.5252.00000 0004 1936 973XDr. von Hauner Children´s Hospital, University of Munich, German Center for Lung Research (DZL), Lindwurmstraße 4, 80337 Munich, Germany
| | - Matthias Kappler
- grid.5252.00000 0004 1936 973XDr. von Hauner Children´s Hospital, University of Munich, German Center for Lung Research (DZL), Lindwurmstraße 4, 80337 Munich, Germany
| | - Florian Stehling
- grid.410718.b0000 0001 0262 7331Uniklinikum Essen Pädiatrische Pneumologie, Kinderheilkunde III, Hufelandstr. 55, 45122 Essen, Germany
| | - Johannes Schulze
- grid.411088.40000 0004 0578 8220Universitätsklinikum Frankfurt Klinik für Kinder- und Jugendmedizin, Pneumologie, Allergologie and Mukoviszidose, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - Winfried Baden
- grid.488549.cUniversitätsklinik für Kinder- und Jugendmedizin Tübingen, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany
| | - Cordula Koerner-Rettberg
- grid.416438.cUniversitätsklinik für Kinder- und Jugendmedizin im St. Josef-Hospital Bochum, Alexandrinenstraße 5, 44791 Bochum, Germany
| | - Julia Carlens
- grid.452624.3Department of Paediatric Pneumonology, Allergology and Neonatology, Hannover Medical School, German Center for Lung Research (DZL), Hannover, Germany
| | - Freerk Prenzel
- grid.9647.c0000 0004 7669 9786Klinik und Poliklinik für Kinder- und Jugendmedizin der Universität Leipzig, Liebigstraße 20a, Haus 6, 04103 Leipzig, Germany
| | - Lutz Nährlich
- grid.440517.3Department of Pediatrics, Justus-Liebig-University Giessen, German Center for Lung Research, Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
| | - Andreas Thalmeier
- grid.411095.80000 0004 0477 2585Pharmacy, University Hospital of Munich, Munich, Germany
| | - Daniela Sebah
- grid.5252.00000 0004 1936 973XDr. von Hauner Children´s Hospital, University of Munich, German Center for Lung Research (DZL), Lindwurmstraße 4, 80337 Munich, Germany
| | - Kai Kronfeld
- grid.410607.4IZKS, Interdisciplinary Center for Clinical Trials, University Medical Center Mainz, Mainz, Germany
| | - Hans Rock
- Central Information Office GmbH, Fronhausen, Bellnhausen, Germany
| | - Christian Ruckes
- grid.410607.4IZKS, Interdisciplinary Center for Clinical Trials, University Medical Center Mainz, Mainz, Germany
| | | | - Martin Wetzke
- grid.452624.3Department of Paediatric Pneumonology, Allergology and Neonatology, Hannover Medical School, German Center for Lung Research (DZL), Hannover, Germany
| | - Elias Seidl
- grid.5252.00000 0004 1936 973XDr. von Hauner Children´s Hospital, University of Munich, German Center for Lung Research (DZL), Lindwurmstraße 4, 80337 Munich, Germany
| | - Nicolaus Schwerk
- grid.452624.3Department of Paediatric Pneumonology, Allergology and Neonatology, Hannover Medical School, German Center for Lung Research (DZL), Hannover, Germany
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16
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Xu KK, Wegner DJ, Geurts LC, Heins HB, Yang P, Hamvas A, Eghtesady P, Sweet SC, Sessions Cole F, Wambach JA. Biologic characterization of ABCA3 variants in lung tissue from infants and children with ABCA3 deficiency. Pediatr Pulmonol 2022; 57:1325-1330. [PMID: 35170262 PMCID: PMC9148430 DOI: 10.1002/ppul.25862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 12/31/2021] [Accepted: 01/24/2022] [Indexed: 11/10/2022]
Abstract
ABCA3 is a phospholipid transporter protein required for surfactant assembly in lamellar bodies of alveolar type II cells. Biallelic pathogenic ABCA3 variants cause severe neonatal respiratory distress syndrome or childhood interstitial lung disease. However, ABCA3 genotype alone does not explain the diversity in disease presentation, severity, and progression. Additionally, monoallelic ABCA3 variants have been reported in infants and children with ABCA3-deficient phenotypes. The effects of most ABCA3 variants identified in patients have not been characterized at the RNA level. ABCA3 allele-specific expression occurs in some cell types due to epigenetic regulation. We obtained lung tissue at transplant or autopsy from 16 infants and children with ABCA3 deficiency due to compound heterozygous ABCA3 variants for biologic characterization of the predicted effects of ABCA3 variants at the RNA level and determination of ABCA3 allele expression. We extracted DNA and RNA from frozen lung tissue and reverse-transcribed cDNA from mRNA. We performed Sanger sequencing to assess allele-specific expression by comparing the heights of variant nucleotide peaks in amplicons from genomic DNA and cDNA. We found similar genomic and cDNA variant nucleotide peak heights and no evidence of allele-specific expression among explant or autopsy samples with biallelic missense ABCA3 variants (n = 6). We observed allele-specific expression of missense alleles in trans with frameshift (n = 4) or nonsense (n = 1) variants, attributable to nonsense-mediated decay. The missense variant c.53 A > G;p.Gln18Arg, located near an exon-intron junction, encoded abnormal splicing with skipping of exon 4. Biologic characterization of ABCA3 variants can inform discovery of variant-specific disease mechanisms.
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Affiliation(s)
- Kathryn K Xu
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Daniel J Wegner
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Lucille C Geurts
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Hillary B Heins
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Ping Yang
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Aaron Hamvas
- Department of Pediatrics, Ann & Robert H. Lurie Children's Hospital of Chicago and Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Pirooz Eghtesady
- Department of Surgery, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Stuart C Sweet
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - F Sessions Cole
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Jennifer A Wambach
- Edward Mallinckrodt Department of Pediatrics, Washington University in St. Louis School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri, USA
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17
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Shaw NC, Kicic A, Fletcher S, Wilton SD, Stick SM, Schultz A. Primary Nasal Epithelial Cells as a Surrogate Cell Culture Model for Type-II Alveolar Cells to Study ABCA-3 Deficiency. Front Med (Lausanne) 2022; 9:827416. [PMID: 35265641 PMCID: PMC8899037 DOI: 10.3389/fmed.2022.827416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/24/2022] [Indexed: 11/13/2022] Open
Abstract
ATP Binding Cassette Subfamily A Member 3 (ABCA-3) is a lipid transporter protein highly expressed in type-II alveolar (AT-II) cells. Mutations in ABCA3 can result in severe respiratory disease in infants and children. To study ABCA-3 deficiency in vitro, primary AT-II cells would be the cell culture of choice although sample accessibility is limited. Our aim was to investigate the suitability of primary nasal epithelial cells, as a surrogate culture model for AT-II cells, to study ABCA-3 deficiency. Expression of ABCA3, and surfactant protein genes, SFTPB and SFTPC, was detected in primary nasal epithelial cells but at a significantly lower level than in AT-II cells. ABCA-3, SP-B, and SP-C were detected by immunofluorescence microscopy in primary nasal epithelial cells. However, SP-B and SP-C were undetectable in primary nasal epithelial cells using western blotting. Structurally imperfect lamellar bodies were observed in primary nasal epithelial cells using transmission electron microscopy. Functional assessment of the ABCA-3 protein demonstrated that higher concentrations of doxorubicin reduced cell viability in ABCA-3 deficient nasal epithelial cells compared to controls in an assay-dependent manner. Our results indicate that there may be a role for primary nasal epithelial cell cultures to model ABCA-3 deficiency in vitro, although additional cell culture models that more effectively recapitulate the AT-II phenotype may be required.
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Affiliation(s)
- Nicole C Shaw
- Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia.,Wal-yan Respiratory Research Centre, Telethon Kids Institute, The University of Western Australia, Perth, WA, Australia
| | - Anthony Kicic
- Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia.,Wal-yan Respiratory Research Centre, Telethon Kids Institute, The University of Western Australia, Perth, WA, Australia.,Centre for Cell Therapy and Regenerative Medicine, School of Medicine and Pharmacology, The University of Western Australia, Perth, WA, Australia.,Department of Respiratory and Sleep Medicine, Perth Children's Hospital, Perth, WA, Australia.,Occupation and Environment, School of Public Health, Curtin University, Perth, WA, Australia
| | - Sue Fletcher
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Sciences, The University of Western Australia, Perth, WA, Australia.,Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
| | - Stephen D Wilton
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Sciences, The University of Western Australia, Perth, WA, Australia.,Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
| | - Stephen M Stick
- Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia.,Wal-yan Respiratory Research Centre, Telethon Kids Institute, The University of Western Australia, Perth, WA, Australia.,Centre for Cell Therapy and Regenerative Medicine, School of Medicine and Pharmacology, The University of Western Australia, Perth, WA, Australia.,Department of Respiratory and Sleep Medicine, Perth Children's Hospital, Perth, WA, Australia
| | - André Schultz
- Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia.,Wal-yan Respiratory Research Centre, Telethon Kids Institute, The University of Western Australia, Perth, WA, Australia.,Department of Respiratory and Sleep Medicine, Perth Children's Hospital, Perth, WA, Australia
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18
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Forstner M, Lin S, Yang X, Kinting S, Rothenaigner I, Schorpp K, Li Y, Hadian K, Griese M. High-content Screen Identifies Cyclosporin A as a Novel ABCA3-specific Molecular Corrector. Am J Respir Cell Mol Biol 2021; 66:382-390. [PMID: 34936540 DOI: 10.1165/rcmb.2021-0223oc] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
ATP-binding cassette (ABC) subfamily A member 3 (ABCA3) is a lipid transporter expressed in alveolar type II cells and localized in the limiting membrane of lamellar bodies. It is crucial for pulmonary surfactant storage and homeostasis. Mutations in the ABCA3 gene are the most common genetic cause of respiratory distress syndrome in mature newborns and interstitial lung disease in children. Apart from lung transplantation, there is no cure available. To address the lack of causal therapeutic options for ABCA3 deficiency, a rapid and reliable approach is needed to investigate variant-specific molecular mechanisms and to identify pharmacological modulators for mono- or combination therapies. To this end, we developed a phenotypic cell-based assay to autonomously identify ABCA3 wild-type-like or mutant-like cells by using machine-learning algorithms aimed at identifying morphological differences in WT and mutant cells. The assay was subsequently used to identify new drug candidates for ABCA3 specific molecular correction by high-content screening of 1,280 food and drug administration-approved small molecules. Cyclosporin A (CsA) was identified as a potent corrector, specific for some, but not all ABCA3 variants. Results were validated by our previously established functional small format assays. Hence, CsA may be selected for orphan drug evaluation in controlled repurposing trials in patients.
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Affiliation(s)
- Maria Forstner
- Ludwig Maximilians University Munich Faculty of Medicine, 54187, Department of Pediatric Pneumology, Dr. von Hauner Children's Hospital, Munchen, Germany.,German Center for Lung Research, 542891, Munich, Germany
| | - Sean Lin
- Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt, 9150, Assay Development and Screening Platform, Neuherberg, Germany
| | - Xiaohua Yang
- Ludwig Maximilians University Munich Faculty of Medicine, 54187, Department of Pediatric Pneumology, Dr. von Hauner Children's Hospital, Munchen, Germany
| | - Susanna Kinting
- Ludwig Maximilians University Munich Faculty of Medicine, 54187, Department of Pediatric Pneumology, Dr. von Hauner Children's Hospital, Munchen, Germany
| | - Ina Rothenaigner
- Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt, 9150, Assay Development and Screening Platform, Neuherberg, Germany
| | - Kenji Schorpp
- Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt, 9150, Assay Development and Screening Platform, Neuherberg, Germany
| | - Yang Li
- Ludwig Maximilians University Munich Faculty of Medicine, 54187, Department of Pediatric Pneumology, Dr. von Hauner Children's Hospital, Munchen, Germany
| | - Kamyar Hadian
- Helmholtz Zentrum Munchen Deutsches Forschungszentrum fur Umwelt und Gesundheit, 9150, Assay Development and Screening Platform, Neuherberg, Germany
| | - Matthias Griese
- Ludwig Maximilians University Munich Faculty of Medicine, 54187, Department of Pediatric Pneumology, Dr. von Hauner Children's Hospital, Munchen, Germany.,German Center for Lung Research, 542891, Munich, Germany;
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19
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Namasivayam V, Stefan K, Pahnke J, Stefan SM. Binding mode analysis of ABCA7 for the prediction of novel Alzheimer's disease therapeutics. Comput Struct Biotechnol J 2021; 19:6490-6504. [PMID: 34976306 PMCID: PMC8666613 DOI: 10.1016/j.csbj.2021.11.035] [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: 09/23/2021] [Revised: 11/20/2021] [Accepted: 11/22/2021] [Indexed: 12/17/2022] Open
Abstract
The adenosine-triphosphate-(ATP)-binding cassette (ABC) transporter ABCA7 is a genetic risk factor for Alzheimer's disease (AD). Defective ABCA7 promotes AD development and/or progression. Unfortunately, ABCA7 belongs to the group of 'under-studied' ABC transporters that cannot be addressed by small-molecules. However, such small-molecules would allow for the exploration of ABCA7 as pharmacological target for the development of new AD diagnostics and therapeutics. Pan-ABC transporter modulators inherit the potential to explore under-studied ABC transporters as novel pharmacological targets by potentially binding to the proposed 'multitarget binding site'. Using the recently reported cryogenic-electron microscopy (cryo-EM) structures of ABCA1 and ABCA4, a homology model of ABCA7 has been generated. A set of novel, diverse, and potent pan-ABC transporter inhibitors has been docked to this ABCA7 homology model for the discovery of the multitarget binding site. Subsequently, application of pharmacophore modelling identified the essential pharmacophore features of these compounds that may support the rational drug design of innovative diagnostics and therapeutics against AD.
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Key Words
- ABC transporter (ABCA1, ABCA4, ABCA7)
- ABC, ATP-binding cassette
- AD, Alzheimer’s disease
- APP, amyloid precursor protein
- ATP, Adenosine-triphosphate
- Alzheimer’s disease (AD)
- BBB, blood-brain barrier
- BODIPY-cholesterol, 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene-cholesterol
- ECD, extracellular domain
- EH, extracellular helix
- GSH, reduced glutathione
- HTS, high-throughput screening
- IC, intracellular helix
- MOE, Molecular Operating Environment
- MSD, membrane spanning domain
- Multitarget modulation (PANABC)
- NBD, nucleotide binding domain
- NBD-cholesterol, 7-nitro-2-1,3-benzoxadiazol-4-yl-cholesterol
- PDB, protein data bank
- PET tracer (PETABC)
- PET, positron emission tomography
- PLIF, protein ligand interaction
- PSO, particle swarm optimization
- Polypharmacology
- R-domain/region, regulatory domain/region
- RMSD, root mean square distance
- Rational drug design and development
- SNP, single-nucleotide polymorphism
- TM, transmembrane helix
- cryo-EM, cryogenic-electron microscopy
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Affiliation(s)
- Vigneshwaran Namasivayam
- Department of Pharmaceutical and Cellbiological Chemistry, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Katja Stefan
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab (www.pahnkelab.eu), University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway
| | - Jens Pahnke
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab (www.pahnkelab.eu), University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway
- LIED, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Jelgavas iela 1, 1004 Rīga, Latvia
| | - Sven Marcel Stefan
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab (www.pahnkelab.eu), University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway
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20
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Onnée M, Fanen P, Callebaut I, de Becdelièvre A. Structure-Based Understanding of ABCA3 Variants. Int J Mol Sci 2021; 22:ijms221910282. [PMID: 34638622 PMCID: PMC8508924 DOI: 10.3390/ijms221910282] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/17/2021] [Accepted: 09/18/2021] [Indexed: 11/16/2022] Open
Abstract
ABCA3 is a crucial protein of pulmonary surfactant biosynthesis, associated with recessive pulmonary disorders such as neonatal respiratory distress and interstitial lung disease. Mutations are mostly private, and accurate interpretation of variants is mandatory for genetic counseling and patient care. We used 3D structure information to complete the set of available bioinformatics tools dedicated to medical decision. Using the experimental structure of human ABCA4, we modeled at atomic resolution the human ABCA3 3D structure including transmembrane domains (TMDs), nucleotide-binding domains (NBDs), and regulatory domains (RDs) in an ATP-bound conformation. We focused and mapped known pathogenic missense variants on this model. We pinpointed amino-acids within the NBDs, the RDs and within the interfaces between the NBDs and TMDs intracellular helices (IHs), which are predicted to play key roles in the structure and/or the function of the ABCA3 transporter. This theoretical study also highlighted the possible impact of ABCA3 variants in the cytosolic part of the protein, such as the well-known p.Glu292Val and p.Arg288Lys variants.
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Affiliation(s)
- Marion Onnée
- Institut Mondor de Recherche Biomédicale, Université Paris Est Creteil, F-94010 Créteil, France; (M.O.); (P.F.)
| | - Pascale Fanen
- Institut Mondor de Recherche Biomédicale, Université Paris Est Creteil, F-94010 Créteil, France; (M.O.); (P.F.)
- AP-HP, Département de Biochimie-Biologie Moléculaire, Pharmacologie, Génétique Médicale, Hôpital Henri Mondor, F-94010 Créteil, France
| | - Isabelle Callebaut
- Institut de Minéralogie de Physique des Matériaux et de Cosmochimie (IMPMC), Muséum National d’Histoire Naturelle, UMR CNRS 7590, Sorbonne Université, F-75005 Paris, France
- Correspondence: (I.C.); (A.d.B.)
| | - Alix de Becdelièvre
- Institut Mondor de Recherche Biomédicale, Université Paris Est Creteil, F-94010 Créteil, France; (M.O.); (P.F.)
- AP-HP, Département de Biochimie-Biologie Moléculaire, Pharmacologie, Génétique Médicale, Hôpital Henri Mondor, F-94010 Créteil, France
- Correspondence: (I.C.); (A.d.B.)
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21
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Dazzo E, Nobile C. Epilepsy-causing Reelin mutations result in impaired secretion and intracellular degradation of mutant proteins. Hum Mol Genet 2021; 31:665-673. [PMID: 34508592 DOI: 10.1093/hmg/ddab271] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/06/2021] [Accepted: 09/06/2021] [Indexed: 01/18/2023] Open
Abstract
Autosomal dominant lateral temporal epilepsy (ADLTE) is a genetically heterogeneous neurologic disorder clinically characterized by focal seizures with auditory symptoms and/or aphasia. About 20% of ADLTE families segregate disease-causing heterozygous mutations in RELN, a brain-expressed gene encoding the secreted protein Reelin. Using a cell-based secretion assay, we show that pathogenic RELN mutations abolish or significantly reduce secretion of mutant proteins, and that this secretion defect results from impaired trafficking of mutant Reelin along the secretory pathway. Confocal immunofluorescence analysis of transiently transfected cells shows that Reelin mutant proteins are degraded by the autophagy system, as revealed by increased formation of autophagosomes immunoreacting with the autophagy markers p62 and LC3. In addition, LC3 immunoblotting shows a significant increase of autophagy flux due to mutant overexpression. Finally, we show that the secretion defect of mutant proteins can be partially rescued by small-molecule correctors. Altogether, these results suggest that Reelin mutant proteins are not properly secreted and that they are degraded through the autophagy pathway.
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Affiliation(s)
- Emanuela Dazzo
- Neuroscience Institute, National Research Council of Italy, Padova, Italy
| | - Carlo Nobile
- Neuroscience Institute, National Research Council of Italy, Padova, Italy
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22
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Ben Saad A, Vauthier V, Tóth Á, Janaszkiewicz A, Durand-Schneider AM, Bruneau A, Delaunay JL, Lapalus M, Mareux E, Garcin I, Gonzales E, Housset C, Aït-Slimane T, Jacquemin E, Di Meo F, Falguières T. Effect of CFTR correctors on the traffic and the function of intracellularly retained ABCB4 variants. Liver Int 2021; 41:1344-1357. [PMID: 33650203 DOI: 10.1111/liv.14839] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 01/25/2021] [Accepted: 02/23/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIM ABCB4 is expressed at the canalicular membrane of hepatocytes. This ATP-binding cassette (ABC) transporter is responsible for the secretion of phosphatidylcholine into bile canaliculi. Missense genetic variations of ABCB4 are correlated with several rare cholestatic liver diseases, the most severe being progressive familial intrahepatic cholestasis type 3 (PFIC3). In a repurposing strategy to correct intracellularly retained ABCB4 variants, we tested 16 compounds previously validated as cystic fibrosis transmembrane conductance regulator (CFTR) correctors. METHODS The maturation, intracellular localization and activity of intracellularly retained ABCB4 variants were analyzed in cell models after treatment with CFTR correctors. In addition, in silico molecular docking calculations were performed to test the potential interaction of CFTR correctors with ABCB4. RESULTS We observed that the correctors C10, C13, and C17, as well as the combinations of C3 + C18 and C4 + C18, allowed the rescue of maturation and canalicular localization of four distinct traffic-defective ABCB4 variants. However, such treatments did not permit a rescue of the phosphatidylcholine secretion activity of these defective variants and were also inhibitory of the activity of wild type ABCB4. In silico molecular docking analyses suggest that these CFTR correctors might directly interact with transmembrane domains and/or ATP-binding sites of the transporter. CONCLUSION Our results illustrate the uncoupling between the traffic and the activity of ABCB4 because the same molecules can rescue the traffic of defective variants while they inhibit the secretion activity of the transporter. We expect that this study will help to design new pharmacological tools with potential clinical interest.
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Affiliation(s)
- Amel Ben Saad
- Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France.,Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France
| | - Virginie Vauthier
- Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France.,Université de Paris, Institut Cochin, Inserm U1016, CNRS UMR 8104, Paris, France
| | - Ágota Tóth
- Inserm, Université de Limoges, UMR 1248 IPPRITT, Limoges, France
| | | | - Anne-Marie Durand-Schneider
- Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France
| | - Alix Bruneau
- Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France.,Department of Hepatology & Gastroenterology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Jean-Louis Delaunay
- Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France
| | - Martine Lapalus
- Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France
| | - Elodie Mareux
- Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France
| | - Isabelle Garcin
- Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France
| | - Emmanuel Gonzales
- Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France.,Assistance Publique - Hôpitaux de Paris, CHU Bicêtre, Paediatric Hepatology & Paediatric Liver Transplant Department, Reference Center for Rare Paediatric Liver Diseases, FILFOIE, ERN Rare-Liver, Faculté de Médecine Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Chantal Housset
- Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France.,Assistance Publique - Hôpitaux de Paris, Hôpital Saint-Antoine, Reference Center for Inflammatory Biliary Diseases and Autoimmune Hepatitis, FILFOIE, ERN Rare-Liver, Paris, France
| | - Tounsia Aït-Slimane
- Inserm, Sorbonne Université, Centre de Recherche Saint-Antoine (CRSA), UMR_S 938, Institute of Cardiometabolism and Nutrition (ICAN), Paris, France
| | - Emmanuel Jacquemin
- Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France.,Assistance Publique - Hôpitaux de Paris, CHU Bicêtre, Paediatric Hepatology & Paediatric Liver Transplant Department, Reference Center for Rare Paediatric Liver Diseases, FILFOIE, ERN Rare-Liver, Faculté de Médecine Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Florent Di Meo
- Inserm, Université de Limoges, UMR 1248 IPPRITT, Limoges, France
| | - Thomas Falguières
- Inserm, Université Paris-Saclay, Physiopathogénèse et traitement des maladies du foie, UMR_S 1193, Orsay, France
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23
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Si X, Steffes LC, Schymick JC, Hazard FK, Tracy MC, Cornfield DN. Three Infants with Pathogenic Variants in the ABCA3 Gene: Presentation, Treatment, and Clinical Course. J Pediatr 2021; 231:278-283.e2. [PMID: 33359301 PMCID: PMC8031471 DOI: 10.1016/j.jpeds.2020.12.055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/17/2020] [Indexed: 11/29/2022]
Abstract
ABCA3 deficiency is a rare cause of neonatal respiratory failure. Biallelic complete loss of function variants lead to neonatal demise without lung transplantation, but children with partial function variants have variable outcomes. The favorable clinical course of 3 such infants presenting with respiratory distress at birth is described.
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Affiliation(s)
- Xin Si
- Division of Pediatric Pulmonary, Center for Excellence in Pulmonary Biology, Asthma and Sleep Medicine, Department of Pediatrics, Stanford University School of Medicine, Lucile Packard Children's Hospital at Stanford University, Stanford, CA.
| | - Lea C Steffes
- Division of Pediatric Pulmonary, Center for Excellence in Pulmonary Biology, Asthma and Sleep Medicine, Department of Pediatrics, Stanford University School of Medicine, Lucile Packard Children's Hospital at Stanford University, Stanford, CA
| | - Jennifer C Schymick
- Division of Medical Genetics, Department of Pediatrics, Stanford University School of Medicine, Lucile Packard Children's Hospital at Stanford University, Stanford, CA
| | - Florette K Hazard
- Division of Pathology, Department of Pediatrics, Stanford University School of Medicine, Lucile Packard Children's Hospital at Stanford University, Stanford, CA
| | - Michael C Tracy
- Division of Pediatric Pulmonary, Center for Excellence in Pulmonary Biology, Asthma and Sleep Medicine, Department of Pediatrics, Stanford University School of Medicine, Lucile Packard Children's Hospital at Stanford University, Stanford, CA
| | - David N Cornfield
- Division of Pediatric Pulmonary, Center for Excellence in Pulmonary Biology, Asthma and Sleep Medicine, Department of Pediatrics, Stanford University School of Medicine, Lucile Packard Children's Hospital at Stanford University, Stanford, CA
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24
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ABCA3 mutations in adult pulmonary fibrosis patients: a case series and review of literature. Curr Opin Pulm Med 2021; 26:293-301. [PMID: 32238781 DOI: 10.1097/mcp.0000000000000680] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE OF REVIEW The current review aims to recognize the variability in clinical presentation of adult patients with bi-allelic ABCA3 mutations, create more depth in ABCA3 mutations reported and highlight the influence of environmental factors on disease course. RECENT FINDINGS Mutations in ABCA3 are predominantly linked to neonatal and pediatric interstitial lung disease (ILD) with a minority surviving beyond puberty. Here, we present three patients with ABCA3 mutations who present with disease at the age of 19, 61 and 77. Moreover, we identified c.4451G>C (p.R1484P), c.1675G>A (p.G559R) and c.4745C>G (p.T1582S) as three novel ABCA3 mutations. In addition, we identified six additional patients with ABCA3 mutations in literature who reached an age above 18. Furthermore, we discuss the influence of infections, drugs and smoking on disease course. SUMMARY Although extremely rare, patients with bi-allelic mutations in ABCA3 may present at adulthood. Late onset of disease may be influenced by type of mutation or environmental factors.
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25
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Wambach JA, Yang P, Wegner DJ, Heins HB, Luke C, Li F, White FV, Cole FS. Functional Genomics of ABCA3 Variants. Am J Respir Cell Mol Biol 2020; 63:436-443. [PMID: 32692933 DOI: 10.1165/rcmb.2020-0034ma] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Rare or private, biallelic variants in the ABCA3 (ATP-binding cassette transporter A3) gene are the most common monogenic cause of lethal neonatal respiratory failure and childhood interstitial lung disease. Functional characterization of fewer than 10% of over 200 disease-associated ABCA3 variants (majority missense) suggests either disruption of ABCA3 protein trafficking (type I) or of ATPase-mediated phospholipid transport (type II). Therapies remain limited and nonspecific. A scalable platform is required for functional characterization of ABCA3 variants and discovery of pharmacologic correctors. To address this need, we first silenced the endogenous ABCA3 locus in A549 cells with CRISPR/Cas9 genome editing. Next, to generate a parent cell line (A549/ABCA3-/-) with a single recombination target site for genomic integration and stable expression of individual ABCA3 missense variant cDNAs, we used lentiviral-mediated integration of a LoxFAS cassette, FACS, and dilutional cloning. To assess the fidelity of this cell-based model, we compared functional characterization (ABCA3 protein processing, ABCA3 immunofluorescence colocalization with intracellular markers, ultrastructural vesicle phenotype) of two individual ABCA3 mutants (type I mutant, p.L101P; type II mutant, p.E292V) in A549/ABCA3-/- cells and in both A549 cells and primary, human alveolar type II cells that transiently express each cDNA after adenoviral-mediated transduction. We also confirmed pharmacologic rescue of ABCA3 variant-encoded mistrafficking and vesicle diameter in A549/ABCA3-/- cells that express p.G1421R (type I mutant). A549/ABCA3-/- cells provide a scalable, genetically versatile, physiologically relevant functional genomics platform for discovery of variant-specific mechanisms that disrupt ABCA3 function and for screening of potential ABCA3 pharmacologic correctors.
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Affiliation(s)
| | - Ping Yang
- Edward Mallinckrodt Department of Pediatrics
| | | | | | - Cliff Luke
- Edward Mallinckrodt Department of Pediatrics
| | - Fuhai Li
- Edward Mallinckrodt Department of Pediatrics.,Institute for Informatics, and
| | - Frances V White
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri
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26
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Hu JY, Yang P, Wegner DJ, Heins HB, Luke CJ, Li F, White FV, Silverman GA, Cole FS, Wambach JA. Functional characterization of four ATP-binding cassette transporter A3 gene (ABCA3) variants. Hum Mutat 2020; 41:1298-1307. [PMID: 32196812 PMCID: PMC7292786 DOI: 10.1002/humu.24014] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 03/08/2020] [Accepted: 03/17/2020] [Indexed: 12/30/2022]
Abstract
ABCA3 transports phospholipids across lamellar body membranes in pulmonary alveolar type II cells and is required for surfactant assembly. Rare, biallelic, pathogenic ABCA3 variants result in lethal neonatal respiratory distress syndrome and childhood interstitial lung disease. Qualitative functional characterization of ABCA3 missense variants suggests two pathogenic classes: disrupted intracellular trafficking (type I mutant) or impaired ATPase-mediated phospholipid transport into the lamellar bodies (type II mutant). We qualitatively compared wild-type (WT-ABCA3) with four uncharacterized ABCA3 variants (c.418A>C;p.Asn140His, c.3609_3611delCTT;p.Phe1203del, c.3784A>G;p.Ser1262Gly, and c.4195G>A;p.Val1399Met) in A549 cells using protein processing, colocalization with intracellular organelles, lamellar body ultrastructure, and ATPase activity. We quantitatively measured lamellar body-like vesicle diameter and intracellular ABCA3 trafficking using fluorescence-based colocalization. Three ABCA3 variants (p.Asn140His, p.Ser1262Gly, and p.Val1399Met) were processed and trafficked normally and demonstrated well-organized lamellar body-like vesicles, but had reduced ATPase activity consistent with type II mutants. P.Phe1203del was processed normally, had reduced ATPase activity, and well-organized lamellar body-like vesicles, but quantitatively colocalized with both endoplasmic reticulum and lysosomal markers, an intermediate phenotype suggesting disruption of both intracellular trafficking and phospholipid transport. All ABCA3 mutants demonstrated mean vesicle diameters smaller than WT-ABCA3. Qualitative and quantitative functional characterization of ABCA3 variants informs mechanisms of pathogenicity.
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Affiliation(s)
- June Y. Hu
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Ping Yang
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Daniel J. Wegner
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Hillary B. Heins
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Cliff J. Luke
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Fuhai Li
- Institute for Informatics, Washington University School of Medicine, St. Louis, Missouri
| | - Frances V. White
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri
| | - Gary A. Silverman
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - F. Sessions Cole
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Jennifer A. Wambach
- Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
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27
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Vece TJ, Wambach JA, Hagood JS. Childhood rare lung disease in the 21st century: "-omics" technology advances accelerating discovery. Pediatr Pulmonol 2020; 55:1828-1837. [PMID: 32533908 PMCID: PMC8711209 DOI: 10.1002/ppul.24809] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/28/2020] [Indexed: 01/14/2023]
Abstract
Childhood rare lung diseases comprise a large number of heterogeneous respiratory disorders that are individually rare but are collectively associated with substantial morbidity, mortality, and healthcare resource utilization. Although the genetic mechanisms for several of these disorders have been elucidated, the pathogenesis mechanisms for others remain poorly understood and treatment options remain limited. Childhood rare lung diseases are enriched for genetic etiologies; identification of the disease mechanisms underlying these rare disorders can inform the biology of normal human lung development and has implications for the treatment of more common respiratory diseases in children and adults. Advances in "-omics" technology, such as genomic sequencing, clinical phenotyping, biomarker discovery, genome editing, in vitro and model organism disease modeling, single-cell analyses, cellular imaging, and high-throughput drug screening have enabled significant progress for diagnosis and treatment of rare childhood lung diseases. The most striking example of this progress has been realized for patients with cystic fibrosis for whom effective, personalized therapies based on CFTR genotype are now available. In this chapter, we focus on recent technology advances in childhood rare lung diseases, acknowledge persistent challenges, and identify promising new technologies that will impact not only biological discovery, but also improve diagnosis, therapies, and survival for children with these rare disorders.
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Affiliation(s)
- Timothy J. Vece
- Division of Pediatric Pulmonology, Program for Rare and Interstitial Lung Disease, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Jennifer A. Wambach
- Division of Newborn Medicine, Edward Mallinckrodt Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - James S. Hagood
- Division of Pediatric Pulmonology, Program for Rare and Interstitial Lung Disease, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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28
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Nathan N, Berdah L, Delestrain C, Sileo C, Clement A. Interstitial lung diseases in children. Presse Med 2020; 49:103909. [PMID: 32563946 DOI: 10.1016/j.lpm.2019.06.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 06/11/2019] [Indexed: 01/16/2023] Open
Abstract
Interstitial lung disease (ILD) in children (chILD) is a heterogeneous group of rare respiratory disorders that are mostly chronic and associated with high morbidity and mortality. The pathogenesis of the various chILD is complex and the diseases share common features of inflammatory and fibrotic changes of the lung parenchyma that impair gas exchanges. The etiologies of chILD are numerous. In this review, we chose to classify them as ILD related to exposure/environment insults, ILD related to systemic and immunological diseases, ILD related to primary lung parenchyma dysfunctions and ILD specific to infancy. A growing part of the etiologic spectrum of chILD is being attributed to molecular defects. Currently, the main genetic mutations associated with chILD are identified in the surfactant genes SFTPA1, SFTPA2, SFTPB, SFTPC, ABCA3 and NKX2-1. Other genetic contributors include mutations in MARS, CSF2RA and CSF2RB in pulmonary alveolar proteinosis, and mutations in TMEM173 and COPA in specific auto-inflammatory forms of chILD. However, only few genotype-phenotype correlations could be identified so far. Herein, information is provided about the clinical presentation and the diagnosis approach of chILD. Despite improvements in patient management, the therapeutic strategies are still relying mostly on corticosteroids although specific therapies are emerging. Larger longitudinal cohorts of patients are being gathered through ongoing international collaborations to improve disease knowledge and targeted therapies. Thus, it is expected that children with ILD will be able to reach the adulthood transition in a better condition.
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Affiliation(s)
- Nadia Nathan
- Pediatric pulmonology department, Trousseau hospital, reference center for rare lung diseases RespiRare, Assistance publique-Hôpitaux de Paris (AP-HP), , 75012 Paris, France; Sorbonne université and Inserm UMRS933, 75012 Paris, France
| | - Laura Berdah
- Pediatric pulmonology department, Trousseau hospital, reference center for rare lung diseases RespiRare, Assistance publique-Hôpitaux de Paris (AP-HP), , 75012 Paris, France; Sorbonne université and Inserm UMRS933, 75012 Paris, France
| | - Céline Delestrain
- Pediatric pulmonology department, Trousseau hospital, reference center for rare lung diseases RespiRare, Assistance publique-Hôpitaux de Paris (AP-HP), , 75012 Paris, France
| | - Chiara Sileo
- Radiology department, AP-HP, Trousseau hospital, 75012 Paris, France
| | - Annick Clement
- Pediatric pulmonology department, Trousseau hospital, reference center for rare lung diseases RespiRare, Assistance publique-Hôpitaux de Paris (AP-HP), , 75012 Paris, France; Sorbonne université and Inserm UMRS933, 75012 Paris, France.
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29
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Liguori L, Monticelli M, Allocca M, Hay Mele B, Lukas J, Cubellis MV, Andreotti G. Pharmacological Chaperones: A Therapeutic Approach for Diseases Caused by Destabilizing Missense Mutations. Int J Mol Sci 2020; 21:ijms21020489. [PMID: 31940970 PMCID: PMC7014102 DOI: 10.3390/ijms21020489] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/08/2020] [Accepted: 01/09/2020] [Indexed: 02/07/2023] Open
Abstract
The term “pharmacological chaperone” was introduced 20 years ago. Since then the approach with this type of drug has been proposed for several diseases, lysosomal storage disorders representing the most popular targets. The hallmark of a pharmacological chaperone is its ability to bind a protein specifically and stabilize it. This property can be beneficial for curing diseases that are associated with protein mutants that are intrinsically active but unstable. The total activity of the affected proteins in the cell is lower than normal because they are cleared by the quality control system. Although most pharmacological chaperones are reversible competitive inhibitors or antagonists of their target proteins, the inhibitory activity is neither required nor desirable. This issue is well documented by specific examples among which those concerning Fabry disease. Direct specific binding is not the only mechanism by which small molecules can rescue mutant proteins in the cell. These drugs and the properly defined pharmacological chaperones can work together with different and possibly synergistic modes of action to revert a disease phenotype caused by an unstable protein.
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Affiliation(s)
- Ludovica Liguori
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania “Luigi Vanvitelli”, 81100 Caserta, Italy; (L.L.); (M.A.)
- Istituto di Chimica Biomolecolare–CNR, 80078 Pozzuoli, Italy;
| | - Maria Monticelli
- Dipartimento di Biologia, Università Federico II, 80126 Napoli, Italy;
| | - Mariateresa Allocca
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania “Luigi Vanvitelli”, 81100 Caserta, Italy; (L.L.); (M.A.)
- Istituto di Chimica Biomolecolare–CNR, 80078 Pozzuoli, Italy;
| | - Bruno Hay Mele
- Integrative Marine Ecology Department, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy;
| | - Jan Lukas
- Translational Neurodegeneration Section “Albrecht-Kossel”, Department of Neurology, University Medical Center Rostock, University of Rostock, 18147 Rostock, Germany;
- Center for Transdisciplinary Neurosciences Rostock (CTNR), University Medical Center Rostock, University of Rostock, 18147 Rostock, Germany
| | - Maria Vittoria Cubellis
- Istituto di Chimica Biomolecolare–CNR, 80078 Pozzuoli, Italy;
- Dipartimento di Biologia, Università Federico II, 80126 Napoli, Italy;
- Correspondence: ; Tel.: +39-081-679118; Fax: +39-081-679233
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30
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Disorders of FZ-CRD; insights towards FZ-CRD folding and therapeutic landscape. Mol Med 2019; 26:4. [PMID: 31892318 PMCID: PMC6938638 DOI: 10.1186/s10020-019-0129-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 12/13/2019] [Indexed: 02/08/2023] Open
Abstract
The ER is hub for protein folding. Proteins that harbor a Frizzled cysteine-rich domain (FZ-CRD) possess 10 conserved cysteine motifs held by a unique disulfide bridge pattern which attains a correct fold in the ER. Little is known about implications of disease-causing missense mutations within FZ-CRD families. Mutations in FZ-CRD of Frizzled class receptor 4 (FZD4) and Muscle, skeletal, receptor tyrosine kinase (MuSK) and Receptor tyrosine kinase-like orphan receptor 2 (ROR2) cause Familial Exudative Vitreoretinopathy (FEVR), Congenital Myasthenic Syndrome (CMS), and Robinow Syndrome (RS) respectively. We highlight reported pathogenic inherited missense mutations in FZ-CRD of FZD4, MuSK and ROR2 which misfold, and traffic abnormally in the ER, with ER-associated degradation (ERAD) as a common pathogenic mechanism for disease. Our review shows that all studied FZ-CRD mutants of RS, FEVR and CMS result in misfolded proteins and/or partially misfolded proteins with an ERAD fate, thus we coin them as “disorders of FZ-CRD”. Abnormal trafficking was demonstrated in 17 of 29 mutants studied; 16 mutants were within and/or surrounding the FZ-CRD with two mutants distant from FZ-CRD. These ER-retained mutants were improperly N-glycosylated confirming ER-localization. FZD4 and MuSK mutants were tagged with polyubiquitin chains confirming targeting for proteasomal degradation. Investigating the cellular and molecular mechanisms of these mutations is important since misfolded protein and ER-targeted therapies are in development. The P344R-MuSK kinase mutant showed around 50% of its in-vitro autophosphorylation activity and P344R-MuSK increased two-fold on proteasome inhibition. M105T-FZD4, C204Y-FZD4, and P344R-MuSK mutants are thermosensitive and therefore, might benefit from extending the investigation to a larger number of chemical chaperones and/or proteasome inhibitors. Nonetheless, FZ-CRD ER-lipidation it less characterized in the literature and recent structural data sheds light on the importance of lipidation in protein glycosylation, proper folding, and ER trafficking. Current treatment strategies in-place for the conformational disease landscape is highlighted. From this review, we envision that disorders of FZ-CRD might be receptive to therapies that target FZ-CRD misfolding, regulation of fatty acids, and/or ER therapies; thus paving the way for a newly explored paradigm to treat different diseases with common defects.
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Li Y, Kinting S, Höppner S, Forstner ME, Uhl O, Koletzko B, Griese M. Metabolic labelling of choline phospholipids probes ABCA3 transport in lamellar bodies. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:158516. [DOI: 10.1016/j.bbalip.2019.158516] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/21/2019] [Accepted: 08/26/2019] [Indexed: 01/09/2023]
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Kinting S, Li Y, Forstner M, Delhommel F, Sattler M, Griese M. Potentiation of ABCA3 lipid transport function by ivacaftor and genistein. J Cell Mol Med 2019; 23:5225-5234. [PMID: 31210424 PMCID: PMC6652914 DOI: 10.1111/jcmm.14397] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/15/2019] [Accepted: 05/03/2019] [Indexed: 12/27/2022] Open
Abstract
ABCA3 is a phospholipid transporter implicated in pulmonary surfactant homoeostasis and localized at the limiting membrane of lamellar bodies, the storage compartment for surfactant in alveolar type II cells. Mutations in ABCA3 display a common genetic cause for diseases caused by surfactant deficiency like respiratory distress in neonates and interstitial lung disease in children and adults, for which currently no causal therapy exists. In this study, we investigated the effects of ivacaftor and genistein, two potentiators of the cystic fibrosis transmembrane conductance regulator (CFTR), on ABCA3-specific lipid transport function. Wild-type (WT) and functional ABCA3 mutations N568D, F629L, G667R, T1114M and L1580P were stably expressed in A549 cells. Three-dimensional modelling predicted functional impairment for all five mutants that was confirmed by in vitro experiments (all <14% of WT functional activity). Treatment with potentiators rescued the mutants N568D (up to 114% of WT), F629L (up to 47% of WT), and G667R (up to 60% of WT), the latter variation needing higher concentrations of genistein, showing reduced affinity of the potentiator to the mutant protein. Our results present a first proof that functional ABCA3 mutations are rescued by CFTR potentiators, making them a potential therapeutical option for patients suffering from surfactant deficiency due to ABCA3 mutations.
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Affiliation(s)
- Susanna Kinting
- Department of Pediatrics, Dr. von Hauner Children's HospitalUniversity Hospital, LMU MunichMunichGermany
- Member of the German Center for Lung Research (DZL)MunichGermany
| | - Yang Li
- Department of Pediatrics, Dr. von Hauner Children's HospitalUniversity Hospital, LMU MunichMunichGermany
| | - Maria Forstner
- Department of Pediatrics, Dr. von Hauner Children's HospitalUniversity Hospital, LMU MunichMunichGermany
- Member of the German Center for Lung Research (DZL)MunichGermany
| | - Florent Delhommel
- Institute of Structural BiologyHelmholtz Zentrum MünchenNeuherbergGermany
- Center for Integrated Protein Science Munich at Department ChemieTechnical University of MunichGarchingGermany
| | - Michael Sattler
- Institute of Structural BiologyHelmholtz Zentrum MünchenNeuherbergGermany
- Center for Integrated Protein Science Munich at Department ChemieTechnical University of MunichGarchingGermany
| | - Matthias Griese
- Department of Pediatrics, Dr. von Hauner Children's HospitalUniversity Hospital, LMU MunichMunichGermany
- Member of the German Center for Lung Research (DZL)MunichGermany
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Cunningham S, Jaffe A, Young LR. Children's interstitial and diffuse lung disease. THE LANCET CHILD & ADOLESCENT HEALTH 2019; 3:568-577. [DOI: 10.1016/s2352-4642(19)30117-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/19/2019] [Accepted: 03/27/2019] [Indexed: 12/21/2022]
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Abstract
PURPOSE OF REVIEW Mutations in genes encoding proteins critical for the production and function of pulmonary surfactant cause diffuse lung disease. Timely recognition and diagnosis of affected individuals is important for proper counseling concerning prognosis and recurrence risk. RECENT FINDINGS Involved genes include those encoding for surfactant proteins A, B, and C, member A3 of the ATP-binding cassette family, and for thyroid transcription factor 1. Clinical presentations overlap and range from severe and rapidly fatal neonatal lung disease to development of pulmonary fibrosis well into adult life. The inheritance patterns, course, and prognosis differ depending upon the gene involved, and in some cases the specific mutation. Treatment options are currently limited, with lung transplantation an option for patients with end-stage pulmonary fibrosis. Additional genetic disorders with overlapping pulmonary phenotypes are being identified through newer methods, although these disorders often involve other organ systems. SUMMARY Genetic disorders of surfactant production are rare but associated with significant morbidity and mortality. Diagnosis can be made invasively through clinically available genetic testing. Improved treatment options are needed and better understanding of the molecular pathophysiology may provide insights into treatments for other lung disorders causing fibrosis.
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Affiliation(s)
- Lawrence M Nogee
- Eudowood Neonatal Pulmonary Division, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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