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Munck S, Cawthorne C, Escamilla‐Ayala A, Kerstens A, Gabarre S, Wesencraft K, Battistella E, Craig R, Reynaud EG, Swoger J, McConnell G. Challenges and advances in optical 3D mesoscale imaging. J Microsc 2022; 286:201-219. [PMID: 35460574 PMCID: PMC9325079 DOI: 10.1111/jmi.13109] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 03/02/2022] [Accepted: 04/14/2022] [Indexed: 12/14/2022]
Abstract
Optical mesoscale imaging is a rapidly developing field that allows the visualisation of larger samples than is possible with standard light microscopy, and fills a gap between cell and organism resolution. It spans from advanced fluorescence imaging of micrometric cell clusters to centimetre-size complete organisms. However, with larger volume specimens, new problems arise. Imaging deeper into tissues at high resolution poses challenges ranging from optical distortions to shadowing from opaque structures. This manuscript discusses the latest developments in mesoscale imaging and highlights limitations, namely labelling, clearing, absorption, scattering, and also sample handling. We then focus on approaches that seek to turn mesoscale imaging into a more quantitative technique, analogous to quantitative tomography in medical imaging, highlighting a future role for digital and physical phantoms as well as artificial intelligence.
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Affiliation(s)
- Sebastian Munck
- VIB‐KU Leuven Center for Brain & Disease ResearchLight Microscopy Expertise Unit & VIB BioImaging CoreLeuvenBelgium
- KU Leuven Department of NeurosciencesLeuven Brain InstituteLeuvenBelgium
| | | | - Abril Escamilla‐Ayala
- VIB‐KU Leuven Center for Brain & Disease ResearchLight Microscopy Expertise Unit & VIB BioImaging CoreLeuvenBelgium
- KU Leuven Department of NeurosciencesLeuven Brain InstituteLeuvenBelgium
| | - Axelle Kerstens
- VIB‐KU Leuven Center for Brain & Disease ResearchLight Microscopy Expertise Unit & VIB BioImaging CoreLeuvenBelgium
- KU Leuven Department of NeurosciencesLeuven Brain InstituteLeuvenBelgium
| | - Sergio Gabarre
- VIB‐KU Leuven Center for Brain & Disease ResearchLight Microscopy Expertise Unit & VIB BioImaging CoreLeuvenBelgium
- KU Leuven Department of NeurosciencesLeuven Brain InstituteLeuvenBelgium
| | | | | | - Rebecca Craig
- Department of Physics, SUPAUniversity of StrathclydeGlasgowUK
| | - Emmanuel G. Reynaud
- School of Biomolecular and Biomedical ScienceUniversity College DublinDublinBelfieldIreland
| | - Jim Swoger
- European Molecular Biology Laboratory (EMBL) BarcelonaBarcelonaSpain
| | - Gail McConnell
- Department of Physics, SUPAUniversity of StrathclydeGlasgowUK
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2
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Yshii L, Pasciuto E, Bielefeld P, Mascali L, Lemaitre P, Marino M, Dooley J, Kouser L, Verschoren S, Lagou V, Kemps H, Gervois P, de Boer A, Burton OT, Wahis J, Verhaert J, Tareen SHK, Roca CP, Singh K, Whyte CE, Kerstens A, Callaerts-Vegh Z, Poovathingal S, Prezzemolo T, Wierda K, Dashwood A, Xie J, Van Wonterghem E, Creemers E, Aloulou M, Gsell W, Abiega O, Munck S, Vandenbroucke RE, Bronckaers A, Lemmens R, De Strooper B, Van Den Bosch L, Himmelreich U, Fitzsimons CP, Holt MG, Liston A. Astrocyte-targeted gene delivery of interleukin 2 specifically increases brain-resident regulatory T cell numbers and protects against pathological neuroinflammation. Nat Immunol 2022; 23:878-891. [PMID: 35618831 PMCID: PMC9174055 DOI: 10.1038/s41590-022-01208-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/11/2022] [Indexed: 12/21/2022]
Abstract
The ability of immune-modulating biologics to prevent and reverse pathology has transformed recent clinical practice. Full utility in the neuroinflammation space, however, requires identification of both effective targets for local immune modulation and a delivery system capable of crossing the blood-brain barrier. The recent identification and characterization of a small population of regulatory T (Treg) cells resident in the brain presents one such potential therapeutic target. Here, we identified brain interleukin 2 (IL-2) levels as a limiting factor for brain-resident Treg cells. We developed a gene-delivery approach for astrocytes, with a small-molecule on-switch to allow temporal control, and enhanced production in reactive astrocytes to spatially direct delivery to inflammatory sites. Mice with brain-specific IL-2 delivery were protected in traumatic brain injury, stroke and multiple sclerosis models, without impacting the peripheral immune system. These results validate brain-specific IL-2 gene delivery as effective protection against neuroinflammation, and provide a versatile platform for delivery of diverse biologics to neuroinflammatory patients.
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Affiliation(s)
- Lidia Yshii
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - Emanuela Pasciuto
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - Pascal Bielefeld
- Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Amsterdam, Netherlands
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Loriana Mascali
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Leuven, Belgium
| | - Pierre Lemaitre
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Leuven, Belgium
| | - Marika Marino
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - James Dooley
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Lubna Kouser
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Stijn Verschoren
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - Vasiliki Lagou
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Leuven, Belgium
| | - Hannelore Kemps
- Cardio & Organ Systems (COST), Biomedical Research Institute (BIOMED), Hasselt University, Diepenbeek, Belgium
| | - Pascal Gervois
- Cardio & Organ Systems (COST), Biomedical Research Institute (BIOMED), Hasselt University, Diepenbeek, Belgium
| | - Antina de Boer
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - Oliver T Burton
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Jérôme Wahis
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - Jens Verhaert
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - Samar H K Tareen
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Carlos P Roca
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Kailash Singh
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Carly E Whyte
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Axelle Kerstens
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
- VIB Bio-Imaging Core, Leuven, Belgium
| | | | | | - Teresa Prezzemolo
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Leuven, Belgium
| | - Keimpe Wierda
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Electrophysiology Expertise Unit, Leuven, Belgium
| | - Amy Dashwood
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Junhua Xie
- VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Faculty of Sciences, Ghent University, Ghent, Belgium
| | - Elien Van Wonterghem
- VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Faculty of Sciences, Ghent University, Ghent, Belgium
| | - Eline Creemers
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Electrophysiology Expertise Unit, Leuven, Belgium
| | - Meryem Aloulou
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
- Toulouse Institute for Infectious and Inflammatory diseases (INFINITY), INSERM UMR1291, CNRS UMR 5051, Toulouse, France
| | - Willy Gsell
- KU Leuven, Department of Imaging and Pathology, Biomedical MRI, Leuven, Belgium
| | - Oihane Abiega
- Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Amsterdam, Netherlands
| | - Sebastian Munck
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
- VIB Bio-Imaging Core, Leuven, Belgium
| | - Roosmarijn E Vandenbroucke
- VIB Center for Inflammation Research, Ghent, Belgium
- Department of Biomedical Molecular Biology, Faculty of Sciences, Ghent University, Ghent, Belgium
| | - Annelies Bronckaers
- Cardio & Organ Systems (COST), Biomedical Research Institute (BIOMED), Hasselt University, Diepenbeek, Belgium
| | - Robin Lemmens
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
- University Hospitals Leuven, Department of Neurology, Leuven, Belgium
| | - Bart De Strooper
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
- Dementia Research Institute, University College London, London, United Kingdom
| | - Ludo Van Den Bosch
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- KU Leuven - Department of Neurosciences, Leuven, Belgium
| | - Uwe Himmelreich
- KU Leuven, Department of Imaging and Pathology, Biomedical MRI, Leuven, Belgium
| | - Carlos P Fitzsimons
- Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Amsterdam, Netherlands
| | - Matthew G Holt
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven - Department of Neurosciences, Leuven, Belgium.
- Instituto de Investigaçāo e Inovaçāo em Saúde (i3S), University of Porto, Porto, Portugal.
| | - Adrian Liston
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.
- KU Leuven, Department of Microbiology, Immunology and Transplantation, Leuven, Belgium.
- Immunology Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom.
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3
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Vanneste M, Mulier M, Nogueira Freitas AC, Van Ranst N, Kerstens A, Voets T, Everaerts W. TRPM3 Is Expressed in Afferent Bladder Neurons and Is Upregulated during Bladder Inflammation. Int J Mol Sci 2021; 23:ijms23010107. [PMID: 35008533 PMCID: PMC8745475 DOI: 10.3390/ijms23010107] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/17/2021] [Accepted: 12/20/2021] [Indexed: 02/06/2023] Open
Abstract
The cation channel TRPM3 is activated by heat and the neurosteroid pregnenolone sulfate. TRPM3 is expressed on sensory neurons innervating the skin, where together with TRPV1 and TRPA1, it functions as one of three redundant sensors of acute heat. Moreover, functional upregulation of TRPM3 during inflammation contributes to heat hyperalgesia. The role of TRPM3 in sensory neurons innervating internal organs such as the bladder is currently unclear. Here, using retrograde labeling and single-molecule fluorescent RNA in situ hybridization, we demonstrate expression of mRNA encoding TRPM3 in a large subset of dorsal root ganglion (DRG) neurons innervating the mouse bladder, and confirm TRPM3 channel functionality in these neurons using Fura-2-based calcium imaging. After induction of cystitis by injection of cyclophosphamide, we observed a robust increase of the functional responses to agonists of TRPM3, TRPV1, and TRPA1 in bladder-innervating DRG neurons. Cystometry and voided spot analysis in control and cyclophosphamide-treated animals did not reveal differences between wild type and TRPM3-deficient mice, indicating that TRPM3 is not critical for normal voiding. We conclude that TRPM3 is functionally expressed in a large proportion of sensory bladder afferent, but its role in bladder sensation remains to be established.
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Affiliation(s)
- Matthias Vanneste
- Laboratory of Ion Channel Research (LICR), VIB-KU Leuven Center for Brain & Disease Research, Belgium & Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium; (M.V.); (M.M.); (A.C.N.F.); (N.V.R.)
| | - Marie Mulier
- Laboratory of Ion Channel Research (LICR), VIB-KU Leuven Center for Brain & Disease Research, Belgium & Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium; (M.V.); (M.M.); (A.C.N.F.); (N.V.R.)
| | - Ana Cristina Nogueira Freitas
- Laboratory of Ion Channel Research (LICR), VIB-KU Leuven Center for Brain & Disease Research, Belgium & Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium; (M.V.); (M.M.); (A.C.N.F.); (N.V.R.)
| | - Nele Van Ranst
- Laboratory of Ion Channel Research (LICR), VIB-KU Leuven Center for Brain & Disease Research, Belgium & Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium; (M.V.); (M.M.); (A.C.N.F.); (N.V.R.)
| | - Axelle Kerstens
- VIB Bio Imaging Core, VIB-KU Leuven Center for Brain & Disease Research, Belgium & Research Group Molecular Neurobiology, Department of Neuroscience, KU Leuven, 3000 Leuven, Belgium;
| | - Thomas Voets
- Laboratory of Ion Channel Research (LICR), VIB-KU Leuven Center for Brain & Disease Research, Belgium & Department of Cellular and Molecular Medicine, KU Leuven, 3000 Leuven, Belgium; (M.V.); (M.M.); (A.C.N.F.); (N.V.R.)
- Correspondence: ; Tel.: +32-16-33-02-17
| | - Wouter Everaerts
- Laboratory of Organ Systems, Department of Development and Regeneration, KU Leuven, Belgium & Department of Urology, University Hospitals Leuven, 3000 Leuven, Belgium;
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4
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Stoklund Dittlau K, Krasnow EN, Fumagalli L, Vandoorne T, Baatsen P, Kerstens A, Giacomazzi G, Pavie B, Rossaert E, Beckers J, Sampaolesi M, Van Damme P, Van Den Bosch L. Generation of Human Motor Units with Functional Neuromuscular Junctions in Microfluidic Devices. J Vis Exp 2021. [PMID: 34570099 DOI: 10.3791/62959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Neuromuscular junctions (NMJs) are specialized synapses between the axon of the lower motor neuron and the muscle facilitating the engagement of muscle contraction. In motor neuron disorders, such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), NMJs degenerate, resulting in muscle atrophy and progressive paralysis. The underlying mechanism of NMJ degeneration is unknown, largely due to the lack of translatable research models. This study aimed to create a versatile and reproducible in vitro model of a human motor unit with functional NMJs. Therefore, human induced pluripotent stem cell (hiPSC)-derived motor neurons and human primary mesoangioblast (MAB)-derived myotubes were co-cultured in commercially available microfluidic devices. The use of fluidically isolated micro-compartments allows for the maintenance of cell-specific microenvironments while permitting cell-to-cell contact through microgrooves. By applying a chemotactic and volumetric gradient, the growth of motor neuron-neurites through the microgrooves promoting myotube interaction and the formation of NMJs were stimulated. These NMJs were identified immunocytochemically through co-localization of motor neuron presynaptic marker synaptophysin (SYP) and postsynaptic acetylcholine receptor (AChR) marker α-bungarotoxin (Btx) on myotubes and characterized morphologically using scanning electron microscopy (SEM). The functionality of the NMJs was confirmed by measuring calcium responses in myotubes upon depolarization of the motor neurons. The motor unit generated using standard microfluidic devices and stem cell technology can aid future research focusing on NMJs in health and disease.
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Affiliation(s)
- Katarina Stoklund Dittlau
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology
| | - Emily N Krasnow
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology
| | - Laura Fumagalli
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology
| | - Tijs Vandoorne
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology
| | - Pieter Baatsen
- VIB Center for Brain & Disease Research, Research Group Molecular Neurobiology, ; VIB Bio Imaging Core, KU Leuven - University of Leuven
| | - Axelle Kerstens
- VIB Center for Brain & Disease Research, Research Group Molecular Neurobiology, ; VIB Bio Imaging Core, KU Leuven - University of Leuven
| | - Giorgia Giacomazzi
- Department of Development and Regeneration, Stem Cell and Developmental Biology, KU Leuven - University of Leuven
| | - Benjamin Pavie
- VIB Center for Brain & Disease Research, Research Group Molecular Neurobiology, ; VIB Bio Imaging Core, KU Leuven - University of Leuven
| | - Elisabeth Rossaert
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology
| | - Jimmy Beckers
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology
| | - Maurilio Sampaolesi
- Department of Development and Regeneration, Stem Cell and Developmental Biology, KU Leuven - University of Leuven
| | - Philip Van Damme
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology, ; Department of Neurology, University Hospitals Leuven
| | - Ludo Van Den Bosch
- Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, KU Leuven - University of Leuven; VIB Center for Brain & Disease Research, Laboratory of Neurobiology, ;
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5
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Stoklund Dittlau K, Krasnow EN, Fumagalli L, Vandoorne T, Baatsen P, Kerstens A, Giacomazzi G, Pavie B, Rossaert E, Beckers J, Sampaolesi M, Van Damme P, Van Den Bosch L. Human motor units in microfluidic devices are impaired by FUS mutations and improved by HDAC6 inhibition. Stem Cell Reports 2021; 16:2213-2227. [PMID: 33891869 PMCID: PMC8452598 DOI: 10.1016/j.stemcr.2021.03.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 03/23/2021] [Accepted: 03/25/2021] [Indexed: 12/13/2022] Open
Abstract
Neuromuscular junctions (NMJs) ensure communication between motor neurons (MNs) and muscle; however, in MN disorders, such as amyotrophic lateral sclerosis (ALS), NMJs degenerate resulting in muscle atrophy. The aim of this study was to establish a versatile and reproducible in vitro model of a human motor unit to investigate the effects of ALS-causing mutations. Therefore, we generated a co-culture of human induced pluripotent stem cell (iPSC)-derived MNs and human primary mesoangioblast-derived myotubes in microfluidic devices. A chemotactic and volumetric gradient facilitated the growth of MN neurites through microgrooves resulting in the interaction with myotubes and the formation of NMJs. We observed that ALS-causing FUS mutations resulted in reduced neurite outgrowth as well as an impaired neurite regrowth upon axotomy. NMJ numbers were likewise reduced in the FUS-ALS model. Interestingly, the selective HDAC6 inhibitor, Tubastatin A, improved the neurite outgrowth, regrowth, and NMJ morphology, prompting HDAC6 inhibition as a potential therapeutic strategy for ALS. Human motor units with functional NMJs can be generated using microfluidic devices FUS-ALS motor units display impaired neurite regrowth, outgrowth and NMJ numbers HDAC6 inhibition alleviate FUS-ALS motor unit pathology in vitro
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Affiliation(s)
- Katarina Stoklund Dittlau
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Emily N Krasnow
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Laura Fumagalli
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Tijs Vandoorne
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Pieter Baatsen
- VIB, Center for Brain & Disease Research, Research Group Molecular Neurobiology, Leuven, Belgium; KU Leuven - University of Leuven, VIB Bio Imaging Core, Leuven, Belgium
| | - Axelle Kerstens
- VIB, Center for Brain & Disease Research, Research Group Molecular Neurobiology, Leuven, Belgium; KU Leuven - University of Leuven, VIB Bio Imaging Core, Leuven, Belgium
| | - Giorgia Giacomazzi
- KU Leuven - University of Leuven, Department of Development and Regeneration, Stem Cell and Developmental Biology, Leuven, Belgium
| | - Benjamin Pavie
- VIB, Center for Brain & Disease Research, Research Group Molecular Neurobiology, Leuven, Belgium; KU Leuven - University of Leuven, VIB Bio Imaging Core, Leuven, Belgium
| | - Elisabeth Rossaert
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Jimmy Beckers
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium
| | - Maurilio Sampaolesi
- KU Leuven - University of Leuven, Department of Development and Regeneration, Stem Cell and Developmental Biology, Leuven, Belgium
| | - Philip Van Damme
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium; University Hospitals Leuven, Department of Neurology, Leuven, Belgium
| | - Ludo Van Den Bosch
- KU Leuven - University of Leuven, Department of Neurosciences, Experimental Neurology, and Leuven Brain Institute, Leuven, Belgium; VIB, Center for Brain & Disease Research, Laboratory of Neurobiology, Leuven, Belgium.
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6
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Van Nieuwenhove E, Barber JS, Neumann J, Smeets E, Willemsen M, Pasciuto E, Prezzemolo T, Lagou V, Seldeslachts L, Malengier-Devlies B, Metzemaekers M, Haßdenteufel S, Kerstens A, van der Kant R, Rousseau F, Schymkowitz J, Di Marino D, Lang S, Zimmermann R, Schlenner S, Munck S, Proost P, Matthys P, Devalck C, Boeckx N, Claessens F, Wouters C, Humblet-Baron S, Meyts I, Liston A. Defective Sec61α1 underlies a novel cause of autosomal dominant severe congenital neutropenia. J Allergy Clin Immunol 2020; 146:1180-1193. [PMID: 32325141 PMCID: PMC7649975 DOI: 10.1016/j.jaci.2020.03.034] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 03/24/2020] [Accepted: 03/27/2020] [Indexed: 12/17/2022]
Abstract
Background The molecular cause of severe congenital neutropenia (SCN) is unknown in 30% to 50% of patients. SEC61A1 encodes the α-subunit of the Sec61 complex, which governs endoplasmic reticulum protein transport and passive calcium leakage. Recently, mutations in SEC61A1 were reported to be pathogenic in common variable immunodeficiency and glomerulocystic kidney disease. Objective Our aim was to expand the spectrum of SEC61A1-mediated disease to include autosomal dominant SCN. Methods Whole exome sequencing findings were validated, and reported mutations were compared by Western blotting, Ca2+ flux assays, differentiation of transduced HL-60 cells, in vitro differentiation of primary CD34 cells, quantitative PCR for unfolded protein response (UPR) genes, and single-cell RNA sequencing on whole bone marrow. Results We identified a novel de novo missense mutation in SEC61A1 (c.A275G;p.Q92R) in a patient with SCN who was born to nonconsanguineous Belgian parents. The mutation results in diminished protein expression, disturbed protein translocation, and an increase in calcium leakage from the endoplasmic reticulum. In vitro differentiation of CD34+ cells recapitulated the patient’s clinical arrest in granulopoiesis. The impact of Q92R-Sec61α1 on neutrophil maturation was validated by using HL-60 cells, in which transduction reduced differentiation into CD11b+CD16+ cells. A potential mechanism for this defect is the uncontrolled initiation of the unfolded protein stress response, with single-cell analysis of primary bone marrow revealing perturbed UPR in myeloid precursors and in vitro differentiation of primary CD34+ cells revealing upregulation of CCAAT/enhancer-binding protein homologous protein and immunoglobulin heavy chain binding protein UPR-response genes. Conclusion Specific mutations in SEC61A1 cause SCN through dysregulation of the UPR.
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Affiliation(s)
- Erika Van Nieuwenhove
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; Department of Pediatrics, University Hospitals Leuven, Leuven, Belgium
| | - John S Barber
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Julika Neumann
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Elien Smeets
- Department of Cellular and Molecular Medicine, Laboratory of Molecular Endocrinology, KU Leuven, Leuven, Belgium
| | - Mathijs Willemsen
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Emanuela Pasciuto
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Teresa Prezzemolo
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Vasiliki Lagou
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Laura Seldeslachts
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium
| | - Bert Malengier-Devlies
- Department of Microbiology and Immunology, Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Mieke Metzemaekers
- Department of Microbiology and Immunology, Laboratory of Molecular Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Sarah Haßdenteufel
- Department of Medical Biochemistry and Molecular Biology, Saarland University, Homburg, Germany
| | - Axelle Kerstens
- VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; VIB Bio Imaging Core & Department for Neuroscience, KU Leuven, Leuven, Belgium
| | - Rob van der Kant
- VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; Department of Cellular and Molecular Medicine, Switch Laboratory, KU Leuven, Leuven, Belgium
| | - Frederic Rousseau
- VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; Department of Cellular and Molecular Medicine, Switch Laboratory, KU Leuven, Leuven, Belgium
| | - Joost Schymkowitz
- VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; Department of Cellular and Molecular Medicine, Switch Laboratory, KU Leuven, Leuven, Belgium
| | - Daniele Di Marino
- Department of Life and Environmental Sciences, New York-Marche Structural Biology Center, Polytechnic University of Marche, Ancona, Italy
| | - Sven Lang
- Department of Medical Biochemistry and Molecular Biology, Saarland University, Homburg, Germany
| | - Richard Zimmermann
- Department of Medical Biochemistry and Molecular Biology, Saarland University, Homburg, Germany
| | - Susan Schlenner
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium
| | - Sebastian Munck
- VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; VIB Bio Imaging Core & Department for Neuroscience, KU Leuven, Leuven, Belgium
| | - Paul Proost
- Department of Microbiology and Immunology, Laboratory of Molecular Immunology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Patrick Matthys
- Department of Microbiology and Immunology, Laboratory of Immunobiology, Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Christine Devalck
- Department of Hemato-Oncology, Hôpital Universitaire Des Enfants Reine Fabiola, Université Libre de Bruxelles, Brussels, Belgium
| | - Nancy Boeckx
- Department of Oncology, KU Leuven, Leuven, Belgium; Department of Laboratory Medicine, University Hospitals Leuven, Leuven, Belgium
| | - Frank Claessens
- Department of Cellular and Molecular Medicine, Laboratory of Molecular Endocrinology, KU Leuven, Leuven, Belgium
| | - Carine Wouters
- Department of Microbiology and Immunology, Immunobiology, KU Leuven, Leuven, Belgium; Department of Pediatrics, Division of Pediatric Rheumatology, University Hospitals Leuven, Leuven, Belgium; ERN-RITA Executive Board, Leuven, Belgium
| | - Stephanie Humblet-Baron
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium
| | - Isabelle Meyts
- Department of Microbiology, Immunology and Transplantation, Laboratory for Inborn Errors of Immunity, KU Leuven, Leuven, Belgium; Department of Pediatrics, Division of Primary Immunodeficiencies, University Hospitals Leuven, Leuven, Belgium; ERN-RITA Core Center, Leuven, Belgium.
| | - Adrian Liston
- Department of Microbiology and Immunology, Laboratory of Adaptive Immunity, KU Leuven, Leuven, Belgium; VIB-KU Leuven Center for Brain and Disease Research, Leuven, Belgium; Laboratory of Lymphocyte Signalling and Development, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom.
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Fogli B, Corthout N, Kerstens A, Bosse F, Klimaschewski L, Munck S, Schweigreiter R. Imaging axon regeneration within synthetic nerve conduits. Sci Rep 2019; 9:10095. [PMID: 31300753 PMCID: PMC6626049 DOI: 10.1038/s41598-019-46579-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 06/28/2019] [Indexed: 11/23/2022] Open
Abstract
While axons within the central nervous system (CNS) do not regenerate following injury, those in the peripheral nervous system (PNS) do, although not in a clinically satisfactory manner as only a small proportion of axons exhibit long-distance regeneration. Moreover, functional recovery is hampered by excessive axonal sprouting and aberrant reinnervation of target tissue. In order to investigate the mechanisms governing the regrowth of axons following injury, previous studies have used lesion paradigms of peripheral nerves in rat or mouse models, and reagents or cells have been administered to the lesion site through nerve conduits, aiming to improve early-stage regeneration. Morphological analysis of such in vivo experiments has however been limited by the incompatibility of synthetic nerve conduits with existing tissue-clearing and imaging techniques. We present herein a novel experimental approach that allows high-resolution imaging of individual axons within nerve conduits, together with quantitative assessment of fiber growth. We used a GFP-expressing mouse strain in a lesion model of the sciatic nerve to describe a strategy that combines nerve clearing, chemical treatment of chitosan nerve conduits, and long working distance confocal microscopy with image processing and analysis. This novel experimental setup provides a means of documenting axon growth within the actual conduit during the critical initial stage of regeneration. This will greatly facilitate the development and evaluation of treatment regimens to improve axonal regeneration following nerve damage.
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Affiliation(s)
- Barbara Fogli
- Innsbruck Medical University, Department of Anatomy, Histology and Embryology, Division of Neuroanatomy, 6020, Innsbruck, Austria
| | - Nikky Corthout
- VIB-KU Leuven Center for Brain & Disease Research O&N 4, Campus Gasthuisberg, 3000, Leuven, Belgium.,KU Leuven, Department for Neuroscience, Campus Gasthuisberg, 3000, Leuven, Belgium.,VIB Bio Imaging Core, Campus Gasthuisberg, 3000, Leuven, Belgium
| | - Axelle Kerstens
- VIB-KU Leuven Center for Brain & Disease Research O&N 4, Campus Gasthuisberg, 3000, Leuven, Belgium.,KU Leuven, Department for Neuroscience, Campus Gasthuisberg, 3000, Leuven, Belgium.,VIB Bio Imaging Core, Campus Gasthuisberg, 3000, Leuven, Belgium
| | - Frank Bosse
- Heinrich-Heine-University Düsseldorf, Department of Neurology, Molecular Neurobiology Laboratory, 40225, Düsseldorf, Germany
| | - Lars Klimaschewski
- Innsbruck Medical University, Department of Anatomy, Histology and Embryology, Division of Neuroanatomy, 6020, Innsbruck, Austria
| | - Sebastian Munck
- VIB-KU Leuven Center for Brain & Disease Research O&N 4, Campus Gasthuisberg, 3000, Leuven, Belgium. .,KU Leuven, Department for Neuroscience, Campus Gasthuisberg, 3000, Leuven, Belgium. .,VIB Bio Imaging Core, Campus Gasthuisberg, 3000, Leuven, Belgium.
| | - Rüdiger Schweigreiter
- Innsbruck Medical University, Biocenter, Division of Neurobiochemistry, 6020, Innsbruck, Austria.
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Martín‐Segura A, Ahmed T, Casadomé‐Perales Á, Palomares‐Perez I, Palomer E, Kerstens A, Munck S, Balschun D, Dotti CG. Age-associated cholesterol reduction triggers brain insulin resistance by facilitating ligand-independent receptor activation and pathway desensitization. Aging Cell 2019; 18:e12932. [PMID: 30884121 PMCID: PMC6516156 DOI: 10.1111/acel.12932] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/30/2019] [Accepted: 02/01/2019] [Indexed: 01/08/2023] Open
Abstract
In the brain, insulin plays an important role in cognitive processes. During aging, these faculties decline, as does insulin signaling. The mechanism behind this last phenomenon is unclear. In recent studies, we reported that the mild and gradual loss of cholesterol in the synaptic fraction of hippocampal neurons during aging leads to a decrease in synaptic plasticity evoked by glutamate receptor activation and also by receptor tyrosine kinase (RTK) signaling. As insulin and insulin growth factor activity are dependent on tyrosine kinase receptors, we investigated whether the constitutive loss of brain cholesterol is also involved in the decay of insulin function with age. Using long‐term depression (LTD) induced by application of insulin to hippocampal slices as a read‐out, we found that the decline in insulin function during aging could be monitored as a progressive impairment of insulin‐LTD. The application of a cholesterol inclusion complex, which donates cholesterol to the membrane and increases membrane cholesterol levels, rescued the insulin signaling deficit and insulin‐LTD. In contrast, extraction of cholesterol from hippocampal neurons of adult mice produced the opposite effect. Furthermore, in vivo inhibition of Cyp46A1, an enzyme involved in brain cholesterol loss with age, improved insulin signaling. Fluorescence resonance energy transfer (FRET) experiments pointed to a change in receptor conformation by reduced membrane cholesterol, favoring ligand‐independent autophosphorylation. Together, these results indicate that changes in membrane fluidity of brain cells during aging play a key role in the decay of synaptic plasticity and cognition that occurs at this late stage of life.
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Affiliation(s)
- Adrián Martín‐Segura
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
- Department of Developmental and Molecular Biology Albert Einstein College of Medicine Bronx New York
| | - Tariq Ahmed
- Faculty of Psychology & Educational Sciences University of Leuven Leuven Belgium
- Neurological Disorders Research Center QBRI‐HBKU Doha Qatar
| | - Álvaro Casadomé‐Perales
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
| | - Irene Palomares‐Perez
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
| | - Ernest Palomer
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
- Cell & Developmental Biology Department University College London London UK
| | - Axelle Kerstens
- Department of Neuroscience, VIB Center for Brain and Disease Research University of Leuven Leuven Belgium
| | - Sebastian Munck
- Department of Neuroscience, VIB Center for Brain and Disease Research University of Leuven Leuven Belgium
| | - Detlef Balschun
- Faculty of Psychology & Educational Sciences University of Leuven Leuven Belgium
| | - Carlos G. Dotti
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa CSIC/UAM Madrid Spain
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9
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Kerstens A, Corthout N, Pavie B, Huang Z, Vernaillen F, Vande Velde G, Munck S. A Label-free Multicolor Optical Surface Tomography (ALMOST) imaging method for nontransparent 3D samples. BMC Biol 2019; 17:1. [PMID: 30616566 PMCID: PMC6323867 DOI: 10.1186/s12915-018-0614-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 11/26/2018] [Indexed: 12/22/2022] Open
Abstract
Background Current mesoscale 3D imaging techniques are limited to transparent or cleared samples or require the use of X-rays. This is a severe limitation for many research areas, as the 3D color surface morphology of opaque samples—for example, intact adult Drosophila, Xenopus embryos, and other non-transparent samples—cannot be assessed. We have developed “ALMOST,” a novel optical method for 3D surface imaging of reflective opaque objects utilizing an optical projection tomography device in combination with oblique illumination and optical filters. Results As well as demonstrating image formation, we provide background information and explain the reconstruction—and consequent rendering—using a standard filtered back projection algorithm and 3D software. We expanded our approach to fluorescence and multi-channel spectral imaging, validating our results with micro-computed tomography. Different biological and inorganic test samples were used to highlight the versatility of our approach. To further demonstrate the applicability of ALMOST, we explored the muscle-induced form change of the Drosophila larva, imaged adult Drosophila, dynamically visualized the closure of neural folds during neurulation of live Xenopus embryos, and showed the complementarity of our approach by comparison with transmitted light and fluorescence OPT imaging of a Xenopus tadpole. Conclusion Thus, our new modality for spectral/color, macro/mesoscopic 3D imaging can be applied to a variety of model organisms and enables the longitudinal surface dynamics during development to be revealed. Electronic supplementary material The online version of this article (10.1186/s12915-018-0614-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Axelle Kerstens
- VIB Bio Imaging Core, Herestraat 49, Box 602, 3000, Leuven, Belgium.,Research Group Molecular Neurobiology, Department of Neuroscience, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium.,VIB Center for Brain and Disease Research, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium
| | - Nikky Corthout
- VIB Bio Imaging Core, Herestraat 49, Box 602, 3000, Leuven, Belgium.,Research Group Molecular Neurobiology, Department of Neuroscience, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium.,VIB Center for Brain and Disease Research, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium
| | - Benjamin Pavie
- VIB Bio Imaging Core, Herestraat 49, Box 602, 3000, Leuven, Belgium.,Research Group Molecular Neurobiology, Department of Neuroscience, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium.,VIB Center for Brain and Disease Research, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium
| | - Zengjin Huang
- VIB Center for Brain and Disease Research, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium.,Neuronal Wiring Lab, Department of Neuroscience, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium
| | - Frank Vernaillen
- VIB BioInformatics Core, Rijvisschestraat 126 3R, 9052, Ghent, Belgium
| | - Greetje Vande Velde
- Department of Imaging and Pathology, KU Leuven - University of Leuven, Herestraat 49, Box 505, 3000, Leuven, Belgium
| | - Sebastian Munck
- VIB Bio Imaging Core, Herestraat 49, Box 602, 3000, Leuven, Belgium. .,Research Group Molecular Neurobiology, Department of Neuroscience, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium. .,VIB Center for Brain and Disease Research, KU Leuven, Herestraat 49, Box 602, 3000, Leuven, Belgium.
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10
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Abstract
Sensor-data processing for the interpretation of a mobile robot's indoor environment, and the manipulation of this data for reliable localization, are still some of the most important issues in robotics. This article presents algorithms that determine the true position of a mobile robot, based on real 2-D and 3-D optical range and inten sity data. We start with the physics of the particular type of sensor used, so that the extraction of reliable and repeatable information (namely, edge coordinates) can be determined, taking into account the noise associated with each range sample and the possibility of optical multiple-path effects. Again, applying the physical model of the sensor, the estimated positions of the mobile robot and the uncertainty in these positions are determined. We demonstrate real experiments using 2-D and 3-D scan data taken in indoor environ ments. To update the robot's position reliably, we address the prob lem of matching the information recorded in a scan to, first, an a priori map, and second, to information recorded in previous scans, eliminating the need for an a priori map.
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Affiliation(s)
- M.D. Adams
- Institute of Robotics Swiss Federal Institute of Technology Zurich, Switzerland
| | - A. Kerstens
- Institute of Robotics Swiss Federal Institute of Technology Zurich, Switzerland
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