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Barrett RLC, Cash D, Simmons C, Kim E, Wood TC, Stones R, Vernon AC, Catani M, Dell'Acqua F. Tissue optimization strategies for high-quality ex vivo diffusion imaging. NMR IN BIOMEDICINE 2023; 36:e4866. [PMID: 36321360 PMCID: PMC10078604 DOI: 10.1002/nbm.4866] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 09/09/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
Ex vivo diffusion imaging can be used to study healthy and pathological tissue microstructure in the rodent brain with high resolution, providing a link between in vivo MRI and ex vivo microscopy techniques. Major challenges for the successful acquisition of ex vivo diffusion imaging data however are changes in the relaxivity and diffusivity of brain tissue following perfusion fixation. In this study we address this question by examining the combined effects of tissue preparation factors that influence signal-to-noise ratio (SNR) and consequently image quality, including fixative concentration, contrast agent concentration and tissue rehydration time. We present an optimization strategy combining these factors to manipulate theT 1 andT 2 of fixed tissue and maximize SNR efficiency. We apply this strategy in the rat brain, for a diffusion-weighted spin echo protocol with TE = 27 ms on a 9.4 T scanner with a 39 mm volume coil and 660 mT/m 114 mm gradient insert. We used a reduced fixative concentration of 2% paraformaldehyde (PFA), rehydration time more than 20 days, 15 mM Gd-DTPA in perfusate and TR 250 ms. This resulted in a doubling of SNR and an increase in SNR per unit time of 135% in cortical grey matter and 88% in white matter compared with 4% PFA and no contrast agent. This improved SNR efficiency enabled the acquisition of excellent-quality high-resolution (78 μ m isotropic voxel size) diffusion data with b = 4000 s/mm2 , 30 diffusion directions and a field of view of 40 × 13 × 18 mm3 in less than 4 days. It was also possible to achieve comparable data quality for a standard resolution (150 μ m) diffusion dataset in 2 1 4 h. In conclusion, the tissue optimization strategy presented here may be used to improve SNR, increase spatial resolution and/or allow faster acquisitions in preclinical ex vivo diffusion MRI experiments.
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Affiliation(s)
- Rachel L. C. Barrett
- NatBrainLab, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
- Sackler Institute for Translational Neurodevelopment, Department of Forensic and Neurodevelopmental Science, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
| | - Camilla Simmons
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
| | - Eugene Kim
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
| | - Tobias C. Wood
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
| | - Richard Stones
- NatBrainLab, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
- Sackler Institute for Translational Neurodevelopment, Department of Forensic and Neurodevelopmental Science, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
| | - Anthony C. Vernon
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology, and Neuroscience, King's College LondonUK
| | - Marco Catani
- NatBrainLab, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
- Sackler Institute for Translational Neurodevelopment, Department of Forensic and Neurodevelopmental Science, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
| | - Flavio Dell'Acqua
- NatBrainLab, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
- Sackler Institute for Translational Neurodevelopment, Department of Forensic and Neurodevelopmental Science, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonUK
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Dadarwal R, Ortiz-Rios M, Boretius S. Fusion of quantitative susceptibility maps and T1-weighted images improve brain tissue contrast in primates. Neuroimage 2022; 264:119730. [PMID: 36332851 DOI: 10.1016/j.neuroimage.2022.119730] [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: 09/28/2021] [Revised: 10/12/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
Recent progress in quantitative susceptibility mapping (QSM) has enabled the accurate delineation of submillimeter-scale subcortical brain structures in humans. However, the simultaneous visualization of cortical, subcortical, and white matter structure remains challenging, utilizing QSM data solely. Here we present TQ-SILiCON, a fusion method that enhances the contrast of cortex and subcortical structures and provides an excellent white matter delineation by combining QSM and conventional T1-weighted (T1w) images. In this study, we first applied QSM in the macaque monkey to map iron-rich subcortical structures. Implementing the same QSM acquisition and analysis methods allowed a similar accurate delineation of subcortical structures in humans. However, the QSM contrast of white and cortical gray matter was not sufficient for appropriate segmentation. Applying automatic brain tissue segmentation to TQ-SILiCON images of the macaque improved the classification of subcortical brain structures as compared to the single T1 contrast by maintaining an excellent white to cortical gray matter contrast. Furthermore, we validated our dual-contrast fusion approach in humans and similarly demonstrated improvements in automated segmentation of the cortex and subcortical structures. We believe the proposed contrast will facilitate translational studies in nonhuman primates to investigate the pathophysiology of neurodegenerative diseases that affect subcortical structures such as the basal ganglia in humans.
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Affiliation(s)
- Rakshit Dadarwal
- Functional Imaging Laboratory, German Primate Center - Leibniz Institute for Primate Research, Göttingen, Germany; Georg-August University of Göttingen, Göttingen, Germany.
| | - Michael Ortiz-Rios
- Functional Imaging Laboratory, German Primate Center - Leibniz Institute for Primate Research, Göttingen, Germany; Leibniz Science Campus Primate Cognition, Göttingen, Germany
| | - Susann Boretius
- Functional Imaging Laboratory, German Primate Center - Leibniz Institute for Primate Research, Göttingen, Germany; Georg-August University of Göttingen, Göttingen, Germany; Leibniz Science Campus Primate Cognition, Göttingen, Germany
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Bolon B, Everitt JI. Selected Resources for Pathology Evaluation of Nonhuman Primates in Nonclinical Safety Assessment. Toxicol Pathol 2022; 50:725-732. [PMID: 35481786 DOI: 10.1177/01926233221091763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Humans and nonhuman primates (NHPs) share numerous anatomical and physiological characteristics, thereby explaining the importance of NHPs as essential animal models for translational medicine and nonclinical toxicity testing. Researchers, toxicologic pathologists, toxicologists, and regulatory reviewers must be familiar with normal and abnormal NHP biological traits when designing, performing, and interpreting data sets from NHP studies. The current compilation presents a list of essential books, journal articles, and websites that provide context to safety assessment and research scientists working with NHP models. The resources used most frequently by the authors have been briefly annotated to permit readers to rapidly ascertain their applicability to particular research endeavors. The references are aimed primarily for toxicologic pathologists working with cynomolgus and rhesus macaques and common marmosets in efficacy and safety assessment studies.
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Affiliation(s)
| | - Jeffrey I Everitt
- Duke University, Department of Pathology, Durham, North Carolina, USA
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Abstract
Hypomyelinating leukodystrophies constitute a subset of genetic white matter disorders characterized by a primary lack of myelin deposition. Most patients with severe hypomyelination present in infancy or early childhood and develop severe neurological deficits, but the clinical presentation can also be mild with onset of symptoms in adolescence or adulthood. MRI can be used to visualize the process of myelination in detail, and MRI pattern recognition can provide a clinical diagnosis in many patients. Next-generation sequencing provides a definitive diagnosis in 80-90% of patients. Genes associated with hypomyelination include those that encode structural myelin proteins but also many that encode proteins involved in RNA translation and some lysosomal proteins. The precise pathomechanisms remain to be elucidated. Improved understanding of the process of myelination, the metabolic axonal support functions of myelin and the proposed contribution of myelin to CNS plasticity provide possible explanations as to why almost all patients with hypomyelination experience slow clinical decline after a long phase of stability. In this Review, we provide an overview of the hypomyelinating leukodystrophies, the advances in our understanding of myelin biology and of the genes involved in these disorders, and the insights these advances have provided into their clinical presentations and evolution.
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Bagnato F, Franco G, Ye F, Fan R, Commiskey P, Smith SA, Xu J, Dortch R. Selective inversion recovery quantitative magnetization transfer imaging: Toward a 3 T clinical application in multiple sclerosis. Mult Scler 2020; 26:457-467. [PMID: 30907234 PMCID: PMC7528886 DOI: 10.1177/1352458519833018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Assessing the degree of myelin injury in patients with multiple sclerosis (MS) is challenging due to the lack of magnetic resonance imaging (MRI) methods specific to myelin quantity. By measuring distinct tissue parameters from a two-pool model of the magnetization transfer (MT) effect, quantitative magnetization transfer (qMT) may yield these indices. However, due to long scan times, qMT has not been translated clinically. OBJECTIVES We aim to assess the clinical feasibility of a recently optimized selective inversion recovery (SIR) qMT and to test the hypothesis that SIR-qMT-derived metrics are informative of radiological and clinical disease-related changes in MS. METHODS A total of 18 MS patients and 9 age- and sex-matched healthy controls (HCs) underwent a 3.0 Tesla (3 T) brain MRI, including clinical scans and an optimized SIR-qMT protocol. Four subjects were re-scanned at a 2-week interval to determine inter-scan variability. RESULTS SIR-qMT measures differed between lesional and non-lesional tissue (p < 0.0001) and between normal-appearing white matter (NAWM) of patients with more advanced disability and normal white matter (WM) of HCs (p < 0.05). SIR-qMT measures were associated with lesion volumes, disease duration, and disability scores (p ⩽ 0.002). CONCLUSION SIR-qMT at 3 T is clinically feasible and predicts both radiological and clinical disease severity in MS.
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Affiliation(s)
- Francesca Bagnato
- Department of Neurology, Neuro-Immunology Division/Neuro-Imaging Unit, Vanderbilt University Medical Center (VUMC), Nashville, TN
| | - Giulia Franco
- Department of Neurology, Neuro-Immunology Division/Neuro-Imaging Unit, Vanderbilt University Medical Center (VUMC), Nashville, TN
- IRCCS Foundation Ca’ Granda Ospedale Maggiore Policlinico, Dino Ferrari Center, Neuroscience Section, Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Fei Ye
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN; USA
| | - Run Fan
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN; USA
| | | | - Seth A. Smith
- Vanderbilt University Institute of Imaging Science; Nashville, TN
| | - Junzhong Xu
- Vanderbilt University Institute of Imaging Science; Nashville, TN
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN
| | - Richard Dortch
- Vanderbilt University Institute of Imaging Science; Nashville, TN
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN
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't Hart BA. Experimental autoimmune encephalomyelitis in the common marmoset: a translationally relevant model for the cause and course of multiple sclerosis. Primate Biol 2019; 6:17-58. [PMID: 32110715 PMCID: PMC7041540 DOI: 10.5194/pb-6-17-2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 03/26/2019] [Indexed: 02/07/2023] Open
Abstract
Aging Western societies are facing an increasing prevalence of chronic
autoimmune-mediated inflammatory disorders (AIMIDs) for which treatments that are safe and effective are scarce. One of the
main reasons for this situation is the lack of animal models, which accurately replicate
clinical and pathological aspects of the human diseases. One important AIMID is the
neuroinflammatory disease multiple sclerosis (MS), for which the mouse experimental
autoimmune encephalomyelitis (EAE) model has been frequently used in preclinical
research. Despite some successes, there is a long list of experimental treatments that
have failed to reproduce promising effects observed in murine EAE models when they were
tested in the clinic. This frustrating situation indicates a wide validity gap between
mouse EAE and MS. This monography describes the development of an EAE model in nonhuman
primates, which may help to bridge the gap.
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Affiliation(s)
- Bert A 't Hart
- Department of Immunobiology, Biomedical Primate Research Centre, Rijswijk, the Netherlands.,Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, the Netherlands
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7
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Bagnato F, Hametner S, Franco G, Pawate S, Sriram S, Lassmann H, Gore J, Smith SE, Dortch R. Selective Inversion Recovery Quantitative Magnetization Transfer Brain MRI at 7T: Clinical and Postmortem Validation in Multiple Sclerosis. J Neuroimaging 2018; 28:380-388. [PMID: 29676026 DOI: 10.1111/jon.12511] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 02/28/2018] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND AND PURPOSE An imaging biomarker of myelin integrity is an unmet need in multiple sclerosis (MS). Selective inversion recovery (SIR) quantitative magnetization transfer imaging (qMT) provides assays of myelin content in the human brain. We previously translated the SIR method to 7T and incorporated a rapid turbo field echo (TFE) readout for whole-brain imaging within clinically acceptable scan times. We herein provide histological validation and test in vivo feasibility and applicability of the SIR-TFE protocol in MS. METHODS Clinical (T1 - and T2 -weighted) and SIR-TFE MRI scans were performed at 7T in a postmortem MS brain and MRI data were acquired in 10 MS patients and 14 heathy volunteers in vivo. The following parameters were estimated from SIR data: the macromolecular-to-free water pool-size-ratio (PSR), the spin-lattice relaxation rate of water (R1f ), and the MT exchange rate (kmf ). Differences in SIR parameters across tissue types, eg, white matter lesions (WM-Ls) and normal appearing WM (NAWM) in patients, and normal white matter (NWM) in heathy volunteers were evaluated. Associations between SIR parameters and disability scores were assessed. RESULTS For postmortem scans, correspondence was observed between WM-Ls and NAWM from histology and PSR/R1f values. In vivo differences were detected for PSR, R1f , and kmf between WM-Ls and NWM (P ≤ .041). Associations were seen between WM-Ls/ NAWM PSR and disability scores (r ≤ -.671, P ≤ .048). CONCLUSIONS SIR-qMT at 7T provides sensitive, quantitative measures of myelin integrity for clinical and research applications.
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Affiliation(s)
- Francesca Bagnato
- Department of Neurology, Neuro-Immunology Division/Neuro-Imaging Unit, Vanderbilt University Medical Center, Nashville, TN
| | - Simon Hametner
- Institute of Brain Pathology, Medical University, Vienna
| | - Giulia Franco
- Department of Neurology, Neuro-Immunology Division/Neuro-Imaging Unit, Vanderbilt University Medical Center, Nashville, TN.,Department of Neurology, University Hospital Policlinico of Milan, Italy
| | - Siddharama Pawate
- Department of Neurology, Neuro-Immunology Division, Vanderbilt University Medical Center, Nashville, TN
| | - Subramaniam Sriram
- Department of Neurology, Neuro-Immunology Division, Vanderbilt University Medical Center, Nashville, TN
| | - Hans Lassmann
- Institute of Brain Pathology, Medical University, Vienna
| | - John Gore
- Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN
| | - Seth E Smith
- Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN
| | - Richard Dortch
- Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN.,Department of Biomedical Engineering, Vanderbilt University, Nashville, TN
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Heath F, Hurley SA, Johansen-Berg H, Sampaio-Baptista C. Advances in noninvasive myelin imaging. Dev Neurobiol 2017; 78:136-151. [PMID: 29082667 PMCID: PMC5813152 DOI: 10.1002/dneu.22552] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 09/18/2017] [Accepted: 10/24/2017] [Indexed: 12/11/2022]
Abstract
Myelin is important for the normal development and healthy function of the nervous system. Recent developments in MRI acquisition and tissue modeling aim to provide a better characterization and more specific markers for myelin. This allows for specific monitoring of myelination longitudinally and noninvasively in the healthy brain as well as assessment of treatment and intervention efficacy. Here, we offer a nontechnical review of MRI techniques developed to specifically monitor myelin such as magnetization transfer (MT) and myelin water imaging (MWI). We further summarize recent studies that employ these methods to measure myelin in relation to development and aging, learning and experience, and neuropathology and psychiatric disorders. © 2017 The Authors. Developmental Neurobiology Published by Wiley Periodicals, Inc. Develop Neurobiol 78: 136–151, 2018
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Affiliation(s)
- Florence Heath
- Oxford Centre for Functional MRI of the Brain, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, United Kingdom
| | - Samuel A Hurley
- Oxford Centre for Functional MRI of the Brain, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, United Kingdom.,Departments of Neuroscience and Radiology, 1111 Highland Ave, University of Wisconsin - Madison, Madison, Wisconsin, 53705
| | - Heidi Johansen-Berg
- Oxford Centre for Functional MRI of the Brain, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, United Kingdom
| | - Cassandra Sampaio-Baptista
- Oxford Centre for Functional MRI of the Brain, Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DU, United Kingdom
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Bonnier G, Maréchal B, Fartaria MJ, Falkowskiy P, Marques JP, Simioni S, Schluep M, Du Pasquier R, Thiran JP, Krueger G, Granziera C. The Combined Quantification and Interpretation of Multiple Quantitative Magnetic Resonance Imaging Metrics Enlightens Longitudinal Changes Compatible with Brain Repair in Relapsing-Remitting Multiple Sclerosis Patients. Front Neurol 2017; 8:506. [PMID: 29021778 PMCID: PMC5623825 DOI: 10.3389/fneur.2017.00506] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 09/08/2017] [Indexed: 12/25/2022] Open
Abstract
Objective Quantitative and semi-quantitative MRI (qMRI) metrics provide complementary specificity and differential sensitivity to pathological brain changes compatible with brain inflammation, degeneration, and repair. Moreover, advanced magnetic resonance imaging (MRI) metrics with overlapping elements amplify the true tissue-related information and limit measurement noise. In this work, we combined multiple advanced MRI parameters to assess focal and diffuse brain changes over 2 years in a group of early-stage relapsing-remitting MS patients. Methods Thirty relapsing-remitting MS patients with less than 5 years disease duration and nine healthy subjects underwent 3T MRI at baseline and after 2 years including T1, T2, T2* relaxometry, and magnetization transfer imaging. To assess longitudinal changes in normal-appearing (NA) tissue and lesions, we used analyses of variance and Bonferroni correction for multiple comparisons. Multivariate linear regression was used to assess the correlation between clinical outcome and multiparametric MRI changes in lesions and NA tissue. Results In patients, we measured a significant longitudinal decrease of mean T2 relaxation times in NA white matter (p = 0.005) and a decrease of T1 relaxation times in the pallidum (p < 0.05), which are compatible with edema reabsorption and/or iron deposition. No longitudinal changes in qMRI metrics were observed in controls. In MS lesions, we measured a decrease in T1 relaxation time (p-value < 2.2e−16) and a significant increase in MTR (p-value < 1e−6), suggesting repair mechanisms, such as remyelination, increased axonal density, and/or a gliosis. Last, the evolution of advanced MRI metrics—and not changes in lesions or brain volume—were correlated to motor and cognitive tests scores evolution (Adj-R2 > 0.4, p < 0.05). In summary, the combination of multiple advanced MRI provided evidence of changes compatible with focal and diffuse brain repair at early MS stages as suggested by histopathological studies.
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Affiliation(s)
- Guillaume Bonnier
- A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Benedicte Maréchal
- Advanced Clinical Imaging Technology (HC CMEA SUI DI BM PI), Siemens Healthcare, Lausanne, Switzerland.,Signal Processing Laboratory 5 LTS5, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Mário João Fartaria
- Advanced Clinical Imaging Technology (HC CMEA SUI DI BM PI), Siemens Healthcare, Lausanne, Switzerland.,Signal Processing Laboratory 5 LTS5, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Pavel Falkowskiy
- Advanced Clinical Imaging Technology (HC CMEA SUI DI BM PI), Siemens Healthcare, Lausanne, Switzerland.,Signal Processing Laboratory 5 LTS5, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - José P Marques
- Donders Centre for Cognitive Neuroimaging, Radbound University, Nijmegen, Netherlands
| | - Samanta Simioni
- Neuropsychology, Institution de Lavigny, Denens, Switzerland
| | - Myriam Schluep
- Neurology Service and Neuroimmunology Laboratory, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland
| | - Renaud Du Pasquier
- Neurology Service and Neuroimmunology Laboratory, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland
| | - Jean-Philippe Thiran
- Signal Processing Laboratory 5 LTS5, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Gunnar Krueger
- Siemens Medical Solutions USA IM MR COL NEZ, Burlington, MA, United States
| | - Cristina Granziera
- A.A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States.,Neurology Service and Neuroimmunology Laboratory, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland
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10
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Matsuda KM, Lopes-Calcas A, Honke ML, O'Brien-Moran Z, Buist R, West M, Martin M. Ex vivo tissue imaging for radiology-pathology correlation: a pilot study with a small bore 7-T MRI in a rare pigmented ganglioglioma exhibiting complex MR signal characteristics associated with melanin and hemosiderin. J Med Imaging (Bellingham) 2017; 4:036001. [PMID: 28924575 PMCID: PMC5596201 DOI: 10.1117/1.jmi.4.3.036001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 08/09/2017] [Indexed: 12/02/2022] Open
Abstract
To advance magnetic resonance imaging (MRI) technologies further for in vivo tissue characterization with histopathologic validation, we investigated the feasibility of ex vivo tissue imaging of a surgically removed human brain tumor as a comprehensive approach for radiology–pathology correlation in histoanatomically identical fashion in a rare case of pigmented ganglioglioma with complex paramagnetic properties. Pieces of surgically removed ganglioglioma, containing melanin and hemosiderin pigments, were imaged with a small bore 7-T MRI scanner to obtain T1-, T2-, and T2*-weighted image and diffusion tensor imaging (DTI). Corresponding histopathological slides were prepared for routine hematoxylin and eosin stain and special stains for melanin and iron/hemosiderin to correlate with MRI signal characteristics. Furthermore, mean diffusivity (MD) maps were generated from DTI data and correlated with cellularity using image analysis. While the presence of melanin was difficult to interpret in in vivo MRI with certainty due to concomitant hemosiderin pigments and calcium depositions, ex vivo tissue imaging clearly demonstrated pieces of tissue exhibiting the characteristic MR signal pattern for melanin with pathologic confirmation in a histoanatomically identical location. There was also concordant correlation between MD and cellularity. Although it is still in an initial phase of development, ex vivo tissue imaging is a promising approach, which offers radiology–pathology correlation in a straightforward and comprehensive manner.
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Affiliation(s)
- Kant M Matsuda
- University of Manitoba, Max Rady College of Medicine, Department of Pathology, Rady Faculty of Health Sciences, Winnipeg, Manitoba, Canada.,Health Sciences Centre Winnipeg, Department of Pathology, Diagnostic Services of Manitoba, Winnipeg, Manitoba, Canada.,Memorial Sloan-Kettering Cancer Center, Department of Pathology, New York, New York, United States
| | - Ana Lopes-Calcas
- University of Manitoba, Max Rady College of Medicine, Department of Pathology, Rady Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Michael L Honke
- University of Winnipeg, Department of Physics, Winnipeg, Manitoba, Canada
| | - Zoe O'Brien-Moran
- University of Winnipeg, Department of Physics, Winnipeg, Manitoba, Canada
| | - Richard Buist
- University of Manitoba, Max Rady College of Medicine, Department of Radiology, Rady Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Michael West
- University of Manitoba, Max Rady College of Medicine, Department of Neurosurgery, Rady Faculty of Health Sciences, Winnipeg, Manitoba, Canada
| | - Melanie Martin
- University of Winnipeg, Department of Physics, Winnipeg, Manitoba, Canada.,University of Manitoba, Max Rady College of Medicine, Department of Radiology, Rady Faculty of Health Sciences, Winnipeg, Manitoba, Canada
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11
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Peixoto-Santos JE, Kandratavicius L, Velasco TR, Assirati JA, Carlotti CG, Scandiuzzi RC, Salmon CEG, Santos ACD, Leite JP. Individual hippocampal subfield assessment indicates that matrix macromolecules and gliosis are key elements for the increased T2 relaxation time seen in temporal lobe epilepsy. Epilepsia 2016; 58:149-159. [PMID: 27864825 DOI: 10.1111/epi.13620] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2016] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Increased T2 relaxation time is often seen in temporal lobe epilepsy (TLE) with hippocampal sclerosis. Water content directly affects the effective T2 in a voxel. Our aim was to evaluate the relation between T2 values and two molecules associated with brain water homeostasis aquaporin 4 (AQP4) and chondroitin sulfate proteoglycan (CSPG), as well as cellular populations in the hippocampal region of patients with TLE. METHODS Hippocampal T2 imaging and diffusion tensor imaging (DTI) were obtained from 42 drug-resistant patients with TLE and 20 healthy volunteers (radiologic controls, RCs). A similar protocol (ex vivo) was applied to hippocampal sections from the same TLE cases and 14 autopsy control hippocampi (histologic and radiologic controls, HRCs), and each hippocampal subfield was evaluated. Hippocampal sections from TLE cases and HRC controls were submitted to immunohistochemistry for neurons (neuron nuclei [NeuN]), reactive astrocytes (glial fibrillary acidic protein [GFAP]), activated microglia (human leukocyte antigen-D-related [HLA-DR]), polarized AQP4, and CSPG. RESULTS Patients with TLE had higher in vivo and ex vivo hippocampal T2 relaxation time. Hippocampi from epilepsy cases had lower neuron density, higher gliosis, decreased AQP4 polarization, and increased CSPG immunoreactive area. In vivo relaxation correlated with astrogliosis in the subiculum and extracellular CSPG in the hilus. Ex vivo T2 relaxation time correlated with astrogliosis in the hilus, CA4, and subiculum, and with microgliosis in CA1. The difference between in vivo and ex vivo relaxation ratio correlated with mean diffusivity and with the immunopositive area for CSPG in the hilus. SIGNIFICANCE Our data indicate that astrogliosis, microgliosis, and CSPG expression correlate with the increased T2 relaxation time seen in the hippocampi of patients with TLE.
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Affiliation(s)
- Jose Eduardo Peixoto-Santos
- Department of Neurosciences and Behavioral Sciences, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Ludmyla Kandratavicius
- Department of Neurosciences and Behavioral Sciences, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Tonicarlo Rodrigues Velasco
- Department of Neurosciences and Behavioral Sciences, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Joao Alberto Assirati
- Department of Surgery and Anatomy, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Carlos Gilberto Carlotti
- Department of Surgery and Anatomy, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Renata Caldo Scandiuzzi
- Department of Neurosciences and Behavioral Sciences, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Carlos Ernesto Garrido Salmon
- Department of Physics and Mathematics, Faculty of Philosophy, Science and Languages of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Antonio Carlos Dos Santos
- Department of Internal Medicine, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Joao Pereira Leite
- Department of Neurosciences and Behavioral Sciences, Ribeirao Preto School of Medicine, University of Sao Paulo, Ribeirao Preto, Brazil
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Maggi P, Sati P, Massacesi L. Magnetic resonance imaging of experimental autoimmune encephalomyelitis in the common marmoset. J Neuroimmunol 2016; 304:86-92. [PMID: 27743612 DOI: 10.1016/j.jneuroim.2016.09.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 09/28/2016] [Indexed: 12/26/2022]
Abstract
Magnetic resonance imaging (MRI) is an invaluable tool for the diagnosis and monitoring of patients with multiple sclerosis (MS) as well as for the study of the disease pathophysiology. Because of its strong clinical, radiological and histopathological similarities with the human disease, experimental autoimmune encephalomyelitis (EAE) in the common marmoset has been studied more intensively over the past several years. Here, we review the current knowledge on MRI in the marmoset EAE, and we outline the physiopathological significance and translational values of these studies with respect to MS. Accumulating evidences suggest that the application of conventional, as well as non-conventional, MRI techniques in the marmoset EAE is a promising approach to elucidate the pathological processes underlying the development of inflammatory demyelinated lesions in the central nervous system, potentially improving the identification and development of new therapeutics.
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Affiliation(s)
- Pietro Maggi
- Department of Neurology, Hôpital Erasme-Université libre de Bruxelles, Belgium
| | - Pascal Sati
- Translational Neuroradiology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Luca Massacesi
- Department of Neurosciences, Drug Research, and Child Health, University of Florence, Florence, Italy
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13
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Helms G, Schlumbohm C, Garea-Rodriguez E, Dechent P, Fuchs E. Pharmacokinetics of the MRI contrast agent gadobutrol in common marmoset monkeys (Callithrix jacchus
). J Med Primatol 2016; 45:290-296. [DOI: 10.1111/jmp.12227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2016] [Indexed: 12/30/2022]
Affiliation(s)
- Gunther Helms
- Department of Cognitive Neurology; Göttingen University Medical Center; Göttingen Germany
- Department of Medical Radiation Physics; Lund University; Lund Sweden
| | | | - Enrique Garea-Rodriguez
- Encepharm; Göttingen Germany
- Department of Neuroanatomy; Albert-Ludwigs-University; Freiburg Germany
- Clinical Neurobiology Laboratory; German Primate Center; Göttingen Germany
| | - Peter Dechent
- Department of Cognitive Neurology; Göttingen University Medical Center; Göttingen Germany
| | - Eberhard Fuchs
- Clinical Neurobiology Laboratory; German Primate Center; Göttingen Germany
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Barkovich AJ, Deon S. Reprint of "Hypomyelinating disorders: An MRI approach. Neurobiol Dis 2016; 92:46-54. [PMID: 27235001 DOI: 10.1016/j.nbd.2015.10.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/10/2015] [Accepted: 10/14/2015] [Indexed: 12/19/2022] Open
Abstract
In recent years, the concept of hypomyelinating disorders has been proposed as a group of disorders with varying systemic manifestations that are identified by MR findings of absence or near absence of the T2 hypointensity that develops in white matter as a result of myelination. Initially proposed as a separate group because they were the largest single category of undiagnosed leukodystrophies, their separation as a distinct group that can be recognized by looking for a specific MRI feature has resulted in a marked increase in their diagnosis and a better understanding of the different causes of hypomyelination. This review will discuss the clinical presentations, imaging findings on standard MRI, and new MRI-related techniques that allow a better understanding of these disorders and proposed methods for quantifying the myelination as a potential means of assessing disease course and the effects of proposed treatments. Disorders with hypomyelination of white matter, or hypomyelinating disorders (HMDs), represent the single largest category among undiagnosed genetic leukoencephalopathies (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010). This group of inborn errors of metabolism is characterized by a magnetic resonance imaging (MRI) appearance of reduced or absent myelin development: delay in the development of T2 hypointensity and, often, T1 hyperintensity in the white matter of the brain. The concept of hypomyelination was first conceptualized by (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010; Schiffmann et al., 1994) in a series of papers that showed that these MRI characteristics were easily recognized, were different from the MRI characteristics of dysmyelinating and demyelinating disorders, and that the combination of these imaging findings with specific other clinical and imaging features could be used to make diagnoses with some confidence. In this manuscript, we will discuss the physiologic and genetic bases of hypomyelinating disorders, as well as their classification, clinical manifestations and imaging characteristics.
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Affiliation(s)
- A James Barkovich
- Neuroradiology Section, Department of Radiology and Biomedical Imaging, UCSF-Benioff Children's Hospital, San Francisco, Q6 CA, United States.
| | - Sean Deon
- University of Colorado Medical Center and Prof. Petra Pouwels, University of Amsterdam
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Abstract
Over the past few decades, MRI-based visualization of demyelinated CNS lesions has become pivotal to the diagnosis and monitoring of multiple sclerosis (MS). In this Review, we outline current efforts to correlate imaging findings with the pathology of lesion development in MS, and the pitfalls that are being encountered in this research. Multimodal imaging at high and ultra-high magnetic field strengths is yielding biologically relevant insights into the pathophysiology of blood-brain barrier dynamics and both active and chronic inflammation, as well as mechanisms of lesion healing and remyelination. Here, we parallel the results in humans with advances in imaging of a primate model of MS - experimental autoimmune encephalomyelitis (EAE) in the common marmoset - in which demyelinated lesions resemble their human counterparts far more closely than do EAE lesions in the rodent. This approach holds promise for the identification of innovative biological markers, and for next-generation clinical trials that will focus more on tissue protection and repair.
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Barkovich AJ, Deon S. Hypomyelinating disorders: An MRI approach. Neurobiol Dis 2015; 87:50-8. [PMID: 26477299 DOI: 10.1016/j.nbd.2015.10.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/10/2015] [Accepted: 10/14/2015] [Indexed: 12/31/2022] Open
Abstract
In recent years, the concept of hypomyelinating disorders has been proposed as a group of disorders with varying systemic manifestations that are identified by MR findings of absence or near absence of the T2 hypointensity that develops in white matter as a result of myelination. Initially proposed as a separate group because they were the largest single category of undiagnosed leukodystrophies, their separation as a distinct group that can be recognized by looking for a specific MRI feature has resulted in a marked increase in their diagnosis and a better understanding of the different causes of hypomyelination. This review will discuss the clinical presentations, imaging findings on standard MRI, and new MRI-related techniques that allow a better understanding of these disorders and proposed methods for quantifying the myelination as a potential means of assessing disease course and the effects of proposed treatments. Disorders with hypomyelination of white matter, or hypomyelinating disorders (HMDs), represent the single largest category among undiagnosed genetic leukoencephalopathies (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010). This group of inborn errors of metabolism is characterized by a magnetic resonance imaging (MRI) appearance of reduced or absent myelin development: delay in the development of T2 hypointensity and, often, T1 hyperintensity in the white matter of the brain. The concept of hypomyelination was first conceptualized by (Schiffmann and van der Knaap, 2009; Steenweg et al., 2010; Schiffmann et al., 1994) in a series of papers that showed that these MRI characteristics were easily recognized, were different from the MRI characteristics of dysmyelinating and demyelinating disorders, and that the combination of these imaging findings with specific other clinical and imaging features could be used to make diagnoses with some confidence. In this manuscript, we will discuss the physiologic and genetic bases of hypomyelinating disorders, as well as their classification, clinical manifestations and imaging characteristics.
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Affiliation(s)
- A James Barkovich
- Neuroradiology Section, Department of Radiology and Biomedical Imaging, UCSF-Benioff Children's Hospital, San Francisco, Q6 CA, United States.
| | - Sean Deon
- University of Colorado Medical Center and Prof. Petra Pouwels, University of Amsterdam
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17
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Jagessar SA, Heijmans N, Blezer ELA, Bauer J, Weissert R, 't Hart BA. Immune profile of an atypical EAE model in marmoset monkeys immunized with recombinant human myelin oligodendrocyte glycoprotein in incomplete Freund's adjuvant. J Neuroinflammation 2015; 12:169. [PMID: 26377397 PMCID: PMC4574133 DOI: 10.1186/s12974-015-0378-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 08/16/2015] [Indexed: 11/21/2022] Open
Abstract
Background Experimental autoimmune encephalomyelitis (EAE) in the common marmoset monkey (Callithrix jacchus) is a relevant preclinical model for translational research into immunopathogenic mechanisms operating in multiple sclerosis (MS). Prior studies showed a core pathogenic role of T and B cells specific for myelin oligodendrocyte glycoprotein (MOG). However, in those studies, the quality of the response against MOG epitopes was strongly biased by bacterial antigens in the complete Freund’s adjuvant (CFA), in which the immunizing recombinant human (rh) MOG protein had been formulated. In response to the need of a more refined EAE model, we have tested whether disease could also be induced with rhMOG in incomplete Freund’s adjuvant (IFA). Method Marmosets were immunized with rhMOG emulsified in IFA in the dorsal skin. Monkeys that did not develop neurological deficit were given booster immunizations at 28-day interval with the same antigen preparation. In a second experiment, three marmoset twin pairs were sensitized against MOG peptides in IFA to study a possibility for suppressive activity towards pathogenic T cells directed against the encephalitogenic epitope MOG40-48. Results Despite the absence of strong danger signals in the rhMOG/IFA inoculum, all monkeys developed clinically evident EAE symptoms. Moreover, in all monkeys, demyelinated lesions were present in the white matter and in two cases also in the cortical grey matter. Immune profiling at height of the disease showed a dominant T cell response against the overlapping peptides 14–36 and 24–46, but reactivity against the pathogenically most relevant peptide 34–56 was conspicuously absent. In the second experiment, there was an indication for a possible suppressive mechanism. Conclusions Immunization of marmoset monkeys with rhMOG in IFA elicits clinical EAE in all animals. Moreover, rhMOG contains pathogenic and regulatory epitopes, but the pathogenic hierarchy of rhMOG epitopes is strongly influenced by the adjuvant in which the protein is formulated. Electronic supplementary material The online version of this article (doi:10.1186/s12974-015-0378-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- S Anwar Jagessar
- Department of Immunobiology, Biomedical Primate Research Centre, P.O. Box 3306, 2280, GH, Rijswijk, The Netherlands. .,ErasMS Centre, Erasmus Medical Center, Rotterdam, The Netherlands.
| | - Nicole Heijmans
- Department of Immunobiology, Biomedical Primate Research Centre, P.O. Box 3306, 2280, GH, Rijswijk, The Netherlands
| | - Erwin L A Blezer
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jan Bauer
- Center for Brain Research, Medical University of Vienna, Vienna, Austria.
| | - Robert Weissert
- Department of Neurology, University of Regensburg, Regensburg, Germany
| | - Bert A 't Hart
- Department of Immunobiology, Biomedical Primate Research Centre, P.O. Box 3306, 2280, GH, Rijswijk, The Netherlands. .,ErasMS Centre, Erasmus Medical Center, Rotterdam, The Netherlands. .,Department of Neuroscience, University of Groningen, Groningen, The Netherlands.
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18
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Vargas WS, Monohan E, Pandya S, Raj A, Vartanian T, Nguyen TD, Hurtado Rúa SM, Gauthier SA. Measuring longitudinal myelin water fraction in new multiple sclerosis lesions. NEUROIMAGE-CLINICAL 2015; 9:369-75. [PMID: 26594620 PMCID: PMC4589846 DOI: 10.1016/j.nicl.2015.09.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 09/05/2015] [Accepted: 09/07/2015] [Indexed: 01/21/2023]
Abstract
Objectives Investigating the potential of myelin repair strategies in multiple sclerosis (MS) requires an understanding of myelin dynamics during lesion evolution. The objective of this study is to longitudinally measure myelin water fraction (MWF), an MRI biomarker of myelin, in new MS lesions and to identify factors that influence their subsequent myelin content. Methods Twenty-three MS patients were scanned with whole-brain Fast Acquisition with Spiral Trajectory and T2prep (FAST-T2) MWF mapping at baseline and median follow-up of 6 months. Eleven healthy controls (HC) confirmed the reproducibility of FAST-T2 in white matter regions of interests (ROIs) similar to a lesion size. A random-effect-model was implemented to determine the association between baseline clinical and lesion variables and the subsequent MWF. Results ROI-based measurements in HCs were highly correlated between scans [mean r = 0.893 (.764–.967)]. In MS patients, 38 gadolinium enhancing (Gd+) and 25 new non-enhancing (Gd−) T2 hyperintense lesions (5.7 months, ±3.8) were identified. Significant improvement in MWF was seen in Gd+ lesions (0.035 ± 0.029, p < 0.001) as compared to Gd− lesions (0.006 ± 0.017, p = 0.065). In the model, a higher baseline MWF (p < 0.001) and the presence of Gd (p < 0.001) were associated with higher subsequent MWF. Conclusions FAST T2 provides a clinically feasible method to quantify MWF in new MS lesions. The observed influence of baseline MWF, which represents a combined effect of both resolving edema and myelin change within acute lesions, suggests that the extent of initial inflammation impacts final myelin recovery. FAST-T2 can measure the extent of myelin loss within early MS lesions. The largest study utilizing an in-vivo MRI method to assess MS lesion change The majority of change occurs in the earliest stages after MS lesion development. The intensity of the acute inflammatory event is detrimental on MWF recovery.
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Affiliation(s)
- Wendy S. Vargas
- Department of Neurology, Weill Cornell Medical College, New York, NY, USA
- Corresponding author at: Department of Neurology, Multiple Sclerosis Center, Weill Cornell Medical College, Suite Y217, 1305 York Ave, New York, NY 10021, USA. Tel.: 646 962 3393; fax: 646 962 0390.Department of NeurologyMultiple Sclerosis CenterWeill Cornell Medical CollegeSuite Y2171305 York AveNew YorkNY10021USA
| | - Elizabeth Monohan
- Department of Neurology, Weill Cornell Medical College, New York, NY, USA
| | - Sneha Pandya
- Department of Radiology, Weill Cornell Medical College, New York, NY, USA
| | - Ashish Raj
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY, USA
- Department of Radiology, Weill Cornell Medical College, New York, NY, USA
| | - Timothy Vartanian
- Department of Neurology, Weill Cornell Medical College, New York, NY, USA
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY, USA
| | - Thanh D. Nguyen
- Department of Radiology, Weill Cornell Medical College, New York, NY, USA
| | | | - Susan A. Gauthier
- Department of Neurology, Weill Cornell Medical College, New York, NY, USA
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY, USA
- Corresponding author at: Department of Neurology, Multiple Sclerosis Center, Weill Cornell Medical College, Suite Y217, 1305 York Ave, New York, NY 10021, USA. Tel.: 646 962 3393; fax: 646 962 0390.Department of NeurologyMultiple Sclerosis CenterWeill Cornell Medical CollegeSuite Y2171305 York AveNew YorkNY10021USA
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Kap YS, van Driel N, Arends R, Rouwendal G, Verolin M, Blezer E, Lycke N, 't Hart BA. Immune modulation by a tolerogenic myelin oligodendrocyte glycoprotein (MOG)10-60 containing fusion protein in the marmoset experimental autoimmune encephalomyelitis model. Clin Exp Immunol 2015; 180:28-39. [PMID: 25393803 DOI: 10.1111/cei.12487] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/30/2014] [Indexed: 01/11/2023] Open
Abstract
Current therapies for multiple sclerosis (MS), a chronic autoimmune neuroinflammatory disease, mostly target general cell populations or immune molecules, which may lead to a compromised immune system. A more directed strategy would be to re-enforce tolerance of the autoaggressive T cells that drive tissue inflammation and injury. In this study, we have investigated whether the course of experimental autoimmune encephalomyelitis (EAE) in mice and marmosets can be altered by a potent tolerizing fusion protein. In addition, a multi-parameter immunological analysis was performed in marmosets to assess whether the treatment induces modulation of EAE-associated cellular and humoral immune reactions. The fusion protein, CTA1R9K-hMOG10-60-DD, contains a mutated cholera toxin A1 subunit (CTA1R9K), a dimer of the Ig binding D region of Staphylococcus aureus protein A (DD), and the human myelin oligodendrocyte glycoprotein (hMOG) sequence 10-60. We observed that intranasal application of CTA1R9K-hMOG10-60-DD seems to skew the immune response against myelin oligodendrocyte glycoprotein (MOG) towards a regulatory function. We show a reduced number of circulating macrophages, reduced MOG-induced expansion of mononuclear cells in peripheral blood, reduced MOG-induced production of interleukin (IL)-17A in spleen, increased MOG-induced production of IL-4 and IL-10 and an increased percentage of cells expressing programmed cell death-1 (PD-1) and CC chemokine receptor 4 (CCR4). Nevertheless, the treatment did not detectably change the EAE course and pathology. Thus, despite a detectable effect on relevant immune parameters, the fusion protein failed to influence the clinical and pathological outcome of disease. This result warrants further development and improvement of this specifically targeted tolerance inducing therapy.
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Affiliation(s)
- Y S Kap
- Department of Immunobiology, Biomedical Primate Research Centre, Rijswijk, The Netherlands; MS Centre ErasMS, Rotterdam, The Netherlands; Department of Immunology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
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Fjær S, Bø L, Myhr KM, Torkildsen Ø, Wergeland S. Magnetization transfer ratio does not correlate to myelin content in the brain in the MOG-EAE mouse model. Neurochem Int 2015; 83-84:28-40. [PMID: 25744931 DOI: 10.1016/j.neuint.2015.02.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 01/29/2015] [Accepted: 02/24/2015] [Indexed: 12/27/2022]
Abstract
Magnetization transfer ratio (MTR) is a magnetic resonance imaging (MRI) method which may detect demyelination not detected by conventional MRI in the central nervous system of patients with multiple sclerosis (MS). A decrease in MTR value has previously been shown to correlate to myelin loss in the mouse cuprizone model for demyelination. In this study, we investigated the sensitivity of MTR for demyelination in the myelin oligodendrocyte (MOG) 1-125 induced experimental autoimmune encephalomyelitis (EAE) mouse model. A total of 24 female c57Bl/6 mice were randomized to a control group (N = 6) or EAE (N = 18). MTR images were obtained at a preclinical 7 Tesla Bruker MR-scanner before EAE induction (baseline), 17-19 days (midpoint) and 31-32 days (endpoint) after EAE induction. Mean MTR values were calculated in five regions of the brain and compared to weight, EAE severity score and myelin content assessed by immunostaining for proteolipid protein and luxol fast blue, lymphocyte and monocyte infiltration and iron deposition. Contrary to what was expected, MTR values in the EAE mice were higher than in the control mice at the midpoint and endpoint. No significant difference in myelin content was found according to histo- or immunohistochemistry. Changes in MTR values did not correlate to myelin content, iron content, lymphocyte or monocyte infiltration, weight or EAE severity scores. This suggest that MTR measures of brain tissue can give significant differences between control mice and EAE mice not caused by demyelination, inflammation or iron deposition, and may not be useful surrogate markers for demyelination in the MOG1-125 mouse model.
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Affiliation(s)
- Sveinung Fjær
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway.
| | - Lars Bø
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Kjell-Morten Myhr
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Øivind Torkildsen
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Stig Wergeland
- KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Bergen, Norway; The Norwegian Multiple Sclerosis Competence Centre, Department of Neurology, Haukeland University Hospital, Bergen, Norway
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21
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Pouwels PJW, Vanderver A, Bernard G, Wolf NI, Dreha-Kulczewksi SF, Deoni SCL, Bertini E, Kohlschütter A, Richardson W, Ffrench-Constant C, Köhler W, Rowitch D, Barkovich AJ. Hypomyelinating leukodystrophies: translational research progress and prospects. Ann Neurol 2014; 76:5-19. [PMID: 24916848 DOI: 10.1002/ana.24194] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 06/05/2014] [Accepted: 06/05/2014] [Indexed: 12/11/2022]
Abstract
Hypomyelinating leukodystrophies represent a genetically heterogeneous but clinically overlapping group of heritable disorders. Current management approaches in the care of the patient with a hypomyelinating leukodystrophy include use of serial magnetic resonance imaging (MRI) to establish and monitor hypomyelination, molecular diagnostics to determine a specific etiology, and equally importantly, careful attention to neurologic complications over time. Emerging research in oligodendrocyte biology and neuroradiology with bedside applications may result in the possibility of clinical trials in the near term, yet there are significant gaps in knowledge in disease classification, characterization, and outcome measures in this group of disorders. Here we review the biological background of myelination, the clinical and genetic variability in hypomyelinating leukodystrophies, and the insights that can be obtained from current MRI techniques. In addition, we discuss ongoing research approaches to define potential outcome markers for future clinical trials.
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Affiliation(s)
- Petra J W Pouwels
- Department of Physics and Medical Technology, VU University Medical Center and Neuroscience Campus Amsterdam, Amsterdam, the Netherlands
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22
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Nathoo N, Yong VW, Dunn JF. Understanding disease processes in multiple sclerosis through magnetic resonance imaging studies in animal models. NEUROIMAGE-CLINICAL 2014; 4:743-56. [PMID: 24936425 PMCID: PMC4053634 DOI: 10.1016/j.nicl.2014.04.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 04/21/2014] [Accepted: 04/22/2014] [Indexed: 01/11/2023]
Abstract
There are exciting new advances in multiple sclerosis (MS) resulting in a growing understanding of both the complexity of the disorder and the relative involvement of grey matter, white matter and inflammation. Increasing need for preclinical imaging is anticipated, as animal models provide insights into the pathophysiology of the disease. Magnetic resonance (MR) is the key imaging tool used to diagnose and to monitor disease progression in MS, and thus will be a cornerstone for future research. Although gadolinium-enhancing and T2 lesions on MRI have been useful for detecting MS pathology, they are not correlative of disability. Therefore, new MRI methods are needed. Such methods require validation in animal models. The increasing necessity for MRI of animal models makes it critical and timely to understand what research has been conducted in this area and what potential there is for use of MRI in preclinical models of MS. Here, we provide a review of MRI and magnetic resonance spectroscopy (MRS) studies that have been carried out in animal models of MS that focus on pathology. We compare the MRI phenotypes of animals and patients and provide advice on how best to use animal MR studies to increase our understanding of the linkages between MR and pathology in patients. This review describes how MRI studies of animal models have been, and will continue to be, used in the ongoing effort to understand MS. MRI studies of pathology in various animal models of MS are reviewed. MRI phenotypes in animal models of MS and MS patients are compared. Animal MRI can increase understanding of links between MR and pathology in patients.
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Affiliation(s)
- Nabeela Nathoo
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
| | - V. Wee Yong
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Jeff F. Dunn
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
- Experimental Imaging Centre, University of Calgary, Calgary, Alberta, Canada
- Corresponding author at: Department of Radiology, University of Calgary, 3330 Hospital Drive, N.W., Calgary, Alberta T2N 4N1, Canada.
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23
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Augustinack JC, van der Kouwe AJ, Fischl B. Medial temporal cortices in ex vivo magnetic resonance imaging. J Comp Neurol 2013; 521:4177-88. [PMID: 23881818 PMCID: PMC6014627 DOI: 10.1002/cne.23432] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 06/27/2013] [Accepted: 07/10/2013] [Indexed: 12/24/2022]
Abstract
This review focuses on the ex vivo magnetic resonance imaging (MRI) modeling of medial temporal cortices and associated structures, the entorhinal verrucae and the perforant pathway. Typical in vivo MRI has limited resolution due to constraints on scan times and does not show laminae in the medial temporal lobe. Recent studies using ex vivo MRI have demonstrated lamina in the entorhinal, perirhinal, and hippocampal cortices. These studies have enabled probabilistic brain mapping that is based on the ex vivo MRI contrast, validated to histology, and subsequently mapped onto an in vivo spherically warped surface model. Probabilistic maps are applicable to other in vivo studies.
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Affiliation(s)
- Jean C. Augustinack
- Athinoula A Martinos Center, Department of Radiology, MGH, Charlestown, Massachusetts 02129
| | | | - Bruce Fischl
- Athinoula A Martinos Center, Department of Radiology, MGH, Charlestown, Massachusetts 02129
- MIT Computer Science and AI Lab, Cambridge, Massachusetts 02139
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24
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Helms G, Garea-Rodriguez E, Schlumbohm C, König J, Dechent P, Fuchs E, Wilke M. Structural and quantitative neuroimaging of the common marmoset monkey using a clinical MRI system. J Neurosci Methods 2013; 215:121-31. [DOI: 10.1016/j.jneumeth.2013.02.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 01/19/2013] [Accepted: 02/14/2013] [Indexed: 01/02/2023]
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Anwar Jagessar S, Fagrouch Z, Heijmans N, Bauer J, Laman JD, Oh L, Migone T, Verschoor EJ, ’t Hart BA. The Different Clinical Effects of Anti-BLyS, Anti-APRIL and Anti-CD20 Antibodies Point at a Critical Pathogenic Role of γ-Herpesvirus Infected B Cells in the Marmoset EAE Model. J Neuroimmune Pharmacol 2013; 8:727-38. [DOI: 10.1007/s11481-013-9448-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 02/27/2013] [Indexed: 11/28/2022]
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B-Cell Depletion Abrogates T Cell-Mediated Demyelination in an Antibody-Nondependent Common Marmoset Experimental Autoimmune Encephalomyelitis Model. J Neuropathol Exp Neurol 2012; 71:716-28. [DOI: 10.1097/nen.0b013e3182622691] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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27
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Samsonov A, Alexander AL, Mossahebi P, Wu YC, Duncan ID, Field AS. Quantitative MR imaging of two-pool magnetization transfer model parameters in myelin mutant shaking pup. Neuroimage 2012; 62:1390-8. [PMID: 22664569 DOI: 10.1016/j.neuroimage.2012.05.077] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 05/07/2012] [Accepted: 05/28/2012] [Indexed: 10/28/2022] Open
Abstract
Magnetization transfer (MT) imaging quantitatively assesses cerebral white matter disease through its sensitivity to macromolecule-bound protons including those associated with myelin proteins and lipid bilayers. However, traditional MT contrast measured by the MT ratio (MTR) lacks pathologic specificity as demyelination, axon loss, inflammation and edema all impact MTR, directly and/or indirectly through multiple covariances among imaging parameters (particularly MTR with T(1)) and tissue features (e.g. axon loss with demyelination). In this study, more complex modeling of MT phenomena ("quantitative" MT or qMT) was applied to a less complex disease model (the myelin mutant shaking [sh] pup, featuring hypomyelination but neither inflammation nor axon loss) in order to eliminate the covariances on both sides of the MR-pathology "equation" and characterize these important relationships free from the usual confounds. qMT measurements were acquired longitudinally in 6 sh pups and 4 age-matched controls ranging from 3 to 21 months of age and compared with histology. The qMT parameter, bound pool fraction (f), was the most distinctive between diseased and control animals; both f and longitudinal relaxation rate R(1) tracked myelination with normal aging, whereas MTR did not--presumably owing to counterbalancing MT and R(1) effects. qMT imaging provides a more accurate and potentially more specific non-invasive tissue characterization.
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Affiliation(s)
- Alexey Samsonov
- Department of Radiology, University of Wisconsin-Madison, Madison, WI 53705, USA.
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28
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Jagessar SA, Heijmans N, Blezer ELA, Bauer J, Blokhuis JH, Wubben JAM, Drijfhout JW, van den Elsen PJ, Laman JD, Hart BA'. Unravelling the T-cell-mediated autoimmune attack on CNS myelin in a new primate EAE model induced with MOG34-56 peptide in incomplete adjuvant. Eur J Immunol 2012; 42:217-27. [PMID: 21928277 DOI: 10.1002/eji.201141863] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 08/22/2011] [Accepted: 09/15/2011] [Indexed: 12/20/2022]
Abstract
Induction of experimental autoimmune encephalomyelitis (EAE) has been documented in common marmosets using peptide 34-56 from human myelin/oligodendrocyte glycoprotein (MOG(34-56) ) in incomplete Freund's adjuvant (IFA). Here, we report that this EAE model is associated with widespread demyelination of grey and white matter. We performed an in-depth analysis of the specificity, MHC restriction and functions of the activated T cells in the model, which likely cause EAE in an autoantibody-independent manner. T-cell lines isolated from blood and lymphoid organs of animals immunized with MOG(34-56) displayed high production of IL-17A and specific lysis of MOG(34-56) -pulsed EBV B-lymphoblastoid cells as typical hallmarks. Cytotoxicity was directed at the epitope MOG(40-48) presented by the non-classical MHC class Ib allele Caja-E, which is orthologue to HLA-E and is expressed in non-inflamed brain. In vivo activated T cells identified by flow cytometry in cultures with MOG(34-56,) comprised CD4(+) CD56(+) and CD4(+) CD8(+) CD56(+) T cells. Furthermore, phenotypical analysis showed that CD4(+) CD8(+) CD56(+) T cells also expressed CD27, but CD16, CD45RO, CD28 and CCR7 were absent. These results show that, in the MOG34-56/IFA marmoset EAE model, a Caja-E-restricted population of autoreactive cytotoxic T cells plays a key role in the process of demyelination in the grey and white matter.
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Affiliation(s)
- S Anwar Jagessar
- Department of Immunology, Biomedical Primate Research Centre, Rijswijk, The Netherlands
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B-cell depletion attenuates white and gray matter pathology in marmoset experimental autoimmune encephalomyelitis. J Neuropathol Exp Neurol 2011; 70:992-1005. [PMID: 22002426 DOI: 10.1097/nen.0b013e318234d421] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
This study investigated the effect of CD20-positive B-cell depletion on central nervous system (CNS) white and gray matter pathology in experimental autoimmune encephalomyelitis in common marmosets, a relevant preclinical model of multiple sclerosis. Experimental autoimmune encephalomyelitis was induced in 14 marmosets by immunization with recombinant human myelin oligodendrocyte glycoprotein in complete Freund adjuvant. At 21 days after immunization, B-cell depletion was achieved by weekly intravenous injections of HuMab 7D8, a human-anti-human CD20 antibody that cross-reacts with marmoset CD20. In vivo magnetic resonance imaging showed widespread brain white matter demyelination in control marmosets that was absent in CD20 antibody-treated marmosets. High-contrast postmortem magnetic resonance imaging showed white matter lesions in 4of the 7 antibody-treated marmosets, but these were significantly smaller than those in controls. The same technique revealed gray matter lesions in 5 control marmosets, but none in antibody-treated marmosets. Histologic analysis confirmed that inflammation, demyelination, and axonal damage were substantially reduced in brain, spinal cord, and optic nerves of CD20 antibody-treated marmosets. In conclusion, CD20-postive B-cell depletion by HuMab 7D8 profoundly reduced the development of both white and gray matter lesions in the marmoset CNS. These data underline the central role of B cells in CNS inflammatory-demyelinating disease.
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30
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Underhill HR, Rostomily RC, Mikheev AM, Yuan C, Yarnykh VL. Fast bound pool fraction imaging of the in vivo rat brain: association with myelin content and validation in the C6 glioma model. Neuroimage 2011; 54:2052-65. [PMID: 21029782 PMCID: PMC3008309 DOI: 10.1016/j.neuroimage.2010.10.065] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 10/18/2010] [Accepted: 10/20/2010] [Indexed: 10/18/2022] Open
Abstract
Cross-relaxation imaging (CRI) is a quantitative magnetic resonance technique that measures the kinetic parameters of magnetization transfer between protons bound to water and protons bound to macromolecules. In this study, in vivo, four-parameter CRI of normal rat brains (N=5) at 3.0 T was first directly compared to histology. The bound pool fraction, f, was strongly associated with myelin density (Pearson's r=0.99, p<0.001). The correlation persisted in separate analyses of gray matter (GM; r=0.89, p=0.046) and white matter (WM; r=0.97, p=0.029). Subsequently, a new time-efficient approach for solely capturing the whole-brain parametric map of f was proposed, validated with histology, and used to estimate myelin density. Since the described approach for the rapid acquisition of f applied constraints to other CRI parameters, a theoretical analysis of error was performed. Estimates of f in normal and pathologic tissue were expected to have <10% error. A comparison of values for f obtained from the traditional four-parameter fit of CRI data versus the proposed rapid acquisition of f was within this expected margin for in vivo rat brain gliomas (N=4; mean±SE; 3.9±0.2% vs. 4.0±0.2%, respectively). In both whole-brain f maps and myelin density maps, replacement of normal GM and WM by proliferating and invading tumor cells could be readily identified. The rapid, whole-brain acquisition of the bound pool fraction may provide a reliable method for detection of glioma invasion in both GM and WM during animal and human imaging.
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Affiliation(s)
- Hunter R Underhill
- Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, WA 98195, USA.
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31
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Kap YS, van Driel N, Blezer E, Parren PWHI, Bleeker WK, Laman JD, Craigen JL, 't Hart BA. Late B cell depletion with a human anti-human CD20 IgG1κ monoclonal antibody halts the development of experimental autoimmune encephalomyelitis in marmosets. THE JOURNAL OF IMMUNOLOGY 2010; 185:3990-4003. [PMID: 20739677 DOI: 10.4049/jimmunol.1001393] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Depletion of CD20(+) B cells has been related to reduced clinical activity in relapsing-remitting multiple sclerosis. The underlying mechanism is not understood, because serum IgG levels were unaltered by the treatment. We report the effect of late B cell depletion on cellular and humoral immune mechanisms in a preclinical multiple sclerosis model (i.e., experimental autoimmune encephalomyelitis [EAE] in the common marmoset). We used a novel human anti-human CD20 IgG1κ mAb (HuMab 7D8) that cross-reacts with marmoset CD20. EAE was induced in 14 marmosets by immunization with recombinant human myelin oligodendrocyte glycoprotein (MOG) in CFA. After 21 d, B cells were depleted in seven monkeys by HuMab 7D8, and seven control monkeys received PBS. The Ab induced profound and long-lasting B cell depletion from PBMCs and lymphoid organs throughout the observation period of 106 d. Whereas all of the control monkeys developed clinically evident EAE, overt neurologic deficits were reduced substantially in three HuMab 7D8-treated monkeys, and four HuMab 7D8-treated monkeys remained completely asymptomatic. The effect of HuMab 7D8 was confirmed on magnetic resonance images, detecting only small lesions in HuMab 7D8-treated monkeys. The infusion of HuMab 7D8 arrested the progressive increase of anti-MOG IgG Abs. Although CD3(+) T cell numbers in lymphoid organs were increased, their proliferation and cytokine production were impaired significantly. Most notable were the substantially reduced mRNA levels of IL-7 and proinflammatory cytokines (IL-6, IL-17A, IFN-γ, and TNF-α). In conclusion, B cell depletion prevents the development of clinical and pathological signs of EAE, which is associated with impaired activation of MOG-reactive T cells in lymphoid organs.
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Affiliation(s)
- Yolanda S Kap
- Department of Immunobiology, Biomedical Primate Research Centre, Rijswijk, The Netherlands
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Effects of early IL-17A neutralization on disease induction in a primate model of experimental autoimmune encephalomyelitis. J Neuroimmune Pharmacol 2010; 6:341-53. [PMID: 20700661 PMCID: PMC3128270 DOI: 10.1007/s11481-010-9238-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 07/28/2010] [Indexed: 11/24/2022]
Abstract
We report on the effect of antibody-mediated neutralization of interleukin (IL)-17A in a non-human primate experimental autoimmune encephalomyelitis (EAE) model induced with recombinant human myelin oligodendrocyte glycoprotein (rhMOG). We tested a human-anti-human IL-17A-antibody in two doses (3 and 30 mg/kg) against placebo (PBS). The treatment was started 1 day before EAE induction and continued throughout the experiment. Although all monkeys developed clinically evident EAE, the onset of neurological signs was delayed in some monkeys from both treatment groups. Total CNS lesion volumes, demyelination, or inflammation did not differ between the different groups. Immune profiling revealed an altered distribution of IL-17A producing cells in the lymphoid organs of antibody-treated monkeys. Comparable numbers of IL-17A producing cells were observed in the brain. RhMOG-induced T cell proliferation in the lymph nodes was slightly reduced after anti-IL-17A antibody treatment. To summarize, we found that anti-IL-17A antibody as a single treatment from disease induction effects a trend towards delayed neurological disease progression in the marmoset EAE model, although the effect did not reach statistical significance. This suggests a role of IL-17A in late stage disease in the marmoset EAE model, but IL-17A may not be the dominant pathogenic cytokine.
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33
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't Hart BA, Jagessar SA, Kap YS, Brok HP. Preclinical models of multiple sclerosis in nonhuman primates. Expert Rev Clin Immunol 2010; 3:749-61. [PMID: 20477025 DOI: 10.1586/1744666x.3.5.749] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Biotechnology has enabled the development of specifically acting therapies for immune-mediated inflammatory disorders (IMIDs) based on biological molecules. The high species specificity precludes safety and effectivity testing in lower species (mice and rats), thus creating a need for valid experimental models in nonhuman primates (NHPs). Here, we review the creation of relevant NHP model(s) for multiple sclerosis (MS), an IMID of the human CNS. We will also discuss how the model(s) can help in the translation of a scientific principle developed in lower species into a therapy for MS.
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Affiliation(s)
- Bert A 't Hart
- Biomedical Primate Research Centre and Erasmus Medical Centre Rotterdam, Rijswijk, The Netherlands.
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34
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Induction of Progressive Demyelinating Autoimmune Encephalomyelitis in Common Marmoset Monkeys Using MOG34-56Peptide in Incomplete Freund Adjuvant. J Neuropathol Exp Neurol 2010; 69:372-85. [DOI: 10.1097/nen.0b013e3181d5d053] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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35
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Pluchino S, Gritti A, Blezer E, Amadio S, Brambilla E, Borsellino G, Cossetti C, Del Carro U, Comi G, 't Hart B, Vescovi A, Martino G. Human neural stem cells ameliorate autoimmune encephalomyelitis in non-human primates. Ann Neurol 2009; 66:343-54. [PMID: 19798728 DOI: 10.1002/ana.21745] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Transplanted neural stem/precursor cells (NPCs) display peculiar therapeutic plasticity in vivo. Although the replacement of cells was first expected as the prime therapeutic mechanism of stem cells in regenerative medicine, it is now clear that transplanted NPCs simultaneously instruct several therapeutic mechanisms, among which replacement of cells might not necessarily prevail. A comprehensive understanding of the mechanism(s) by which NPCs exert their therapeutic plasticity is lacking. This study was designed as a preclinical approach to test the feasibility of human NPC transplantation in an outbreed nonhuman primate experimental autoimmune encephalomyelitis (EAE) model approximating the clinical and complex neuropathological situation of human multiple sclerosis (MS) more closely than EAE in the standard laboratory rodent. METHODS We examined the safety and efficacy of the intravenous (IV) and intrathecal (IT) administration of human NPCs in common marmosets affected by human myelin oligodendrocyte glycoprotein 1-125-induced EAE. Treatment commenced upon the occurrence of detectable brain lesions on a 4.7T spectrometer. RESULTS EAE marmosets injected IV or IT with NPCs accumulated lower disability and displayed increased survival, as compared with sham-treated controls. Transplanted NPCs persisted within the host central nervous system (CNS), but were also found in draining lymph nodes, for up to 3 months after transplantation and exhibited remarkable immune regulatory capacity in vitro. INTERPRETATION Herein, we provide the first evidence that human CNS stem cells ameliorate EAE in nonhuman primates without overt side effects. Immune regulation (rather than neural differentiation) is suggested as the major putative mechanism by which NPCs ameliorate EAE in vivo. Our findings represent a critical step toward the clinical use of human NPCs in MS.
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Affiliation(s)
- Stefano Pluchino
- Neuroimmunology Unit, San Raffaele Scientific Institute, Milan, Italy.
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36
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Kap YS, Laman JD, 't Hart BA. Experimental autoimmune encephalomyelitis in the common marmoset, a bridge between rodent EAE and multiple sclerosis for immunotherapy development. J Neuroimmune Pharmacol 2009; 5:220-30. [PMID: 19826959 DOI: 10.1007/s11481-009-9178-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Accepted: 09/29/2009] [Indexed: 12/22/2022]
Abstract
The attrition rate of new drugs for central nervous system diseases including multiple sclerosis (MS) is very high. A widely recognized bottleneck in the selection of promising central nervous system drug candidates from the development pipeline is the lack of sufficiently predictive animal models. Here, we review how the experimental autoimmune encephalomyelitis (EAE) model in the Neotropical primate "common marmoset" can help to bridge the gap between rodent EAE models and MS. The EAE model in the marmoset closely resembles MS in the clinical as well as pathological presentation and can be used for fundamental research into immunopathogenic mechanisms and for therapy development. We discuss recent insights arising from this model, both on novel therapeutics and immunopathogenesis.
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Affiliation(s)
- Yolanda S Kap
- Department of Immunobiology, Biomedical Primate Research Centre, P.O. Box 3306, 2280, GH, Rijswijk, The Netherlands
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37
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Burman KJ, Rosa MG. Architectural subdivisions of medial and orbital frontal cortices in the marmoset monkey (Callithrix jacchus). J Comp Neurol 2009; 514:11-29. [DOI: 10.1002/cne.21976] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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38
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Clinical, pathological, and immunologic aspects of the multiple sclerosis model in common marmosets (Callithrix jacchus). J Neuropathol Exp Neurol 2009; 68:341-55. [PMID: 19337065 DOI: 10.1097/nen.0b013e31819f1d24] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The efficacy of many new immunomodulatory therapies for multiple sclerosis (MS) patients has often been disappointing, reflecting our incomplete understanding of this enigmatic disease. There is a growing awareness that, at least in part, there may be limited applicability to the human disease of results obtained in the widely studied MS model experimental autoimmune encephalomyelitis in rodents. This review describes the experimental autoimmune encephalomyelitis model developed in a small neotropical primate, the common marmoset (Callithrix jacchus). The model has features including clinicopathologic correlation patterns, lesion heterogeneity, immunologic mechanisms, and disease markers that more closely mimic the human disease. Several unique features of experimental autoimmune encephalomyelitis in marmosets, together with their outbred nature and close genetic and immunologic similarities to humans, create an attractive experimental model for translational research into MS, particularly for the preclinical evaluation of new biologic therapeutic molecules that cannot be investigated in rodents because of their species specificity. Moreover, this model provides new insights into possible pathogenetic mechanisms in MS.
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39
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Distinct spatiotemporal pattern of CNS lesions revealed by USPIO-enhanced MRI in MOG-induced EAE rats implicates the involvement of spino-olivocerebellar pathways. J Neuroimmunol 2009; 211:49-55. [PMID: 19346009 DOI: 10.1016/j.jneuroim.2009.03.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Revised: 02/16/2009] [Accepted: 03/05/2009] [Indexed: 11/22/2022]
Abstract
USPIO-enhanced MRI allows non-invasive visualization of mononuclear cell infiltration into CNS lesions in MS and EAE. Herein, we show a distinct spatiotemporal pattern of CNS lesions that reveals the involvement of spino-olivocerebellar pathways in MOG-induced EAE rats using USPIO-enhanced MRI. Specifically, lesions of the inferior olives were observed primarily in the acute phase whereas lesions of cerebellum or spinal cord/brainstem were observed during the relapse phase. Further, behavioral deficits observed from these animals are consistent with the functional role of spino-olivocerebellar pathways in coordination and movement. Collectively, our results provide new insights into the pathophysiology of this animal model of MS.
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Ou X, Sun SW, Liang HF, Song SK, Gochberg DF. Quantitative magnetization transfer measured pool-size ratio reflects optic nerve myelin content in ex vivo mice. Magn Reson Med 2009; 61:364-71. [PMID: 19165898 DOI: 10.1002/mrm.21850] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Optic nerves from mice that have undergone retinal ischemia were examined using a newly implemented quantitative magnetization transfer (qMT) technique. Previously published results indicate that the optic nerve from retinal ischemia mice suffered significant axon degeneration without detectable myelin injury at 3 days after reperfusion. At this time point, we acquired ex vivo qMT parameters from both shiverer mice (which have nearly no myelin) and control mice that have undergone retinal ischemia, and these qMT measures were compared with diffusion tensor imaging (DTI) results. Our findings suggests that the qMT estimated ratio of the pool sizes of the macromolecular and free water protons reflected the different myelin contents in the optic nerves between the shiverer and control mice. This pool size ratio was specific to myelin content only and was not significantly affected by the presence of axon injury in mouse optic nerve 3 days after retinal ischemia.
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Affiliation(s)
- Xiawei Ou
- Department of Radiology, Vanderbilt University Institute of Imaging Science, Nashville, Tennessee 37232-2310, USA.
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41
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McCreary CR, Bjarnason TA, Skihar V, Mitchell JR, Yong VW, Dunn JF. Multiexponential T2 and magnetization transfer MRI of demyelination and remyelination in murine spinal cord. Neuroimage 2009; 45:1173-82. [PMID: 19349232 DOI: 10.1016/j.neuroimage.2008.12.071] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 12/23/2008] [Accepted: 12/31/2008] [Indexed: 11/19/2022] Open
Abstract
Identification of remyelination is important in the evaluation of potential treatments of demyelinating diseases such as multiple sclerosis. Local injection of lysolecithin into the brain or spinal cord provides a murine model of demyelination with spontaneous remyelination. The aim of this study was to determine if quantitative, multicomponent T(2) (qT(2)) analysis and magnetization transfer ratio (MTR), both indicative of myelin content, could detect changes in myelination, particularly remyelination, of the cervical spinal cord in mice treated with lysolecithin. We found that the myelin water fraction and geometric mean T(2) value of the intra/extracellular water significantly decreased at 14 days then returned to control levels by 28 days after injury, corresponding to clearance of myelin debris and remyelination which was shown by eriochrome cyanine and oil red O staining of histological sections. The MTR was significantly decreased 14 days after lysolecithin injection, and remained low over the time course studied. Evidence of demyelination shown by both qT(2) and MTR lagged behind the histological evidence of demyelination. Myelin water fraction increased with remyelination, however MTR remained lower after 28 days. The difference between qT(2) and MTR may identify early remyelination.
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Affiliation(s)
- Cheryl R McCreary
- Experimental Imaging Centre, University of Calgary, Calgary, AB, Canada
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42
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Hiestand PC, Rausch M, Meier DP, Foster CA. Ascomycete derivative to MS therapeutic: S1P receptor modulator FTY720. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2008; 66:361, 363-81. [PMID: 18416311 DOI: 10.1007/978-3-7643-8595-8_8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Fingolimod (FTY720) represents the first in a new class of immune-modulators whose target is sphingosine-1-phosphate (S1P) receptors. It was first identified by researchers at Kyoto University and Yoshitomi Pharmaceutical as a chemical derivative of the ascomycete metabolite ISP-1 (myriocin). Unlike its natural product parent, FTY720 does not interfere with sphingolipid biosynthesis. Instead, its best characterized mechanism of action upon in vivo phosphorylation, leading to the active principle FTY720-P, is the rapid and reversible inhibition of lymphocyte egress from peripheral lymph nodes. As a consequence of S1P1 receptor internalization, tissue-damaging T-cells can not recirculate and infiltrate sites of inflammation such as the central nervous system (CNS). Furthermore, FTY720-P modulation of S1P receptor signaling also enhances endothelial barrier function. Due to its mode of action, FTY720 effectively prevents transplant rejection and is active in various autoimmune disease models. The most striking efficacy is in the multiple sclerosis (MS) model of experimental autoimmune encephalomyelitis, which has now been confirmed in the clinic. FTY720 demonstrated promising results in Phase II trials and recently entered Phase III in patients with relapsing MS. Emerging evidence suggests that its efficacy in the CNS extends beyond immunomodulation to encompass other aspects of MS pathophysiology, including an influence on the blood-brain-barrier and glial repair mechanisms that could ultimately contribute to restoration of nerve function. FTY720 may represent a potent new therapeutic modality in MS, combined with the benefit of oral administration.
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Boretius S, Gadjanski I, Demmer I, Bähr M, Diem R, Michaelis T, Frahm J. MRI of optic neuritis in a rat model. Neuroimage 2008; 41:323-34. [DOI: 10.1016/j.neuroimage.2008.02.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Revised: 01/24/2008] [Accepted: 02/14/2008] [Indexed: 11/27/2022] Open
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Autoimmunity Against Myelin Oligodendrocyte Glycoprotein Is Dispensable for the Initiation Although Essential for the Progression of Chronic Encephalomyelitis in Common Marmosets. J Neuropathol Exp Neurol 2008; 67:326-40. [DOI: 10.1097/nen.0b013e31816a6851] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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45
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't Hart BA, Hintzen RQ, Laman JD. Preclinical assessment of therapeutic antibodies against human CD40 and human interleukin-12/23p40 in a nonhuman primate model of multiple sclerosis. NEURODEGENER DIS 2008; 5:38-52. [PMID: 18075274 DOI: 10.1159/000109937] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Accepted: 01/11/2007] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Proinflammatory cytokines, such as interleukin (IL)-12 and IL-23, and costimulatory molecules on antigen-presenting cells (APC), such as CD40, are critical to autoreactive T cell activation by APC, and hence, are considered relevant targets of therapy for immune-mediated inflammatory diseases (IMID). OBJECTIVE The current review discusses the preclinical evaluation of two novel immunotherapeutic monoclonal antibodies (mAbs), one directed against human IL-12/23p40 and the other against CD40. As the antibodies only recognize their target molecule in primates, the efficacy could not be tested in rodent models. RESULTS As a preclinical IMID model for the in vivo evaluation of both mAbs, we have used the experimental autoimmune/allergic encephalomyelitis (EAE) model in common marmoset monkeys (Callithrix jacchus). Both mAbs show beneficial activities in the EAE model when administered early in disease development as well as after the onset of brain inflammation. The treatment effects were evaluated using a combination of quantitative magnetic resonance imaging and a series of ex vivo and immunopathological evaluations. CONCLUSION The promising effects during ongoing disease in a relevant preclinical IMID model illustrate the potential of these two antibodies as treatment of IMID, in particular for multiple sclerosis on which disease EAE has been modeled.
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Affiliation(s)
- Bert A 't Hart
- Department of Immunobiology, Biomedical Primate Research Centre, Rijswijk, The Netherlands.
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Kap YS, Smith P, Jagessar SA, Remarque E, Blezer E, Strijkers GJ, Laman JD, Hintzen RQ, Bauer J, Brok HPM, 't Hart BA. Fast progression of recombinant human myelin/oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis in marmosets is associated with the activation of MOG34-56-specific cytotoxic T cells. THE JOURNAL OF IMMUNOLOGY 2008; 180:1326-37. [PMID: 18209026 DOI: 10.4049/jimmunol.180.3.1326] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The recombinant human (rh) myelin/oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) model in the common marmoset is characterized by 100% disease incidence, a chronic disease course, and a variable time interval between immunization and neurological impairment. We investigated whether monkeys with fast and slow disease progression display different anti-MOG T or B cell responses and analyzed the underlying pathogenic mechanism(s). The results show that fast progressor monkeys display a significantly wider specificity diversification of anti-MOG T cells at necropsy than slow progressors, especially against MOG(34-56) and MOG(74-96). MOG(34-56) emerged as a critical encephalitogenic peptide, inducing severe neurological disease and multiple lesions with inflammation, demyelination, and axonal injury in the CNS. Although EAE was not observed in MOG(74-96)-immunized monkeys, weak T cell responses against MOG(34-56) and low grade CNS pathology were detected. When these cases received a booster immunization with MOG(34-56) in IFA, full-blown EAE developed. MOG(34-56)-reactive T cells expressed CD3, CD4, or CD8 and CD56, but not CD16. Moreover, MOG(34-56)-specific T cell lines displayed specific cytotoxic activity against peptide-pulsed B cell lines. The phenotype and cytotoxic activity suggest that these cells are NK-CTL. These results support the concept that cytotoxic cells may play a role in the pathogenesis of multiple sclerosis.
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Affiliation(s)
- Yolanda S Kap
- Department of Immunobiology, Biomedical Primate Research Centre, Rijswijk, The Netherlands
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Laule C, Vavasour IM, Kolind SH, Li DKB, Traboulsee TL, Moore GRW, MacKay AL. Magnetic resonance imaging of myelin. Neurotherapeutics 2007; 4:460-84. [PMID: 17599712 PMCID: PMC7479725 DOI: 10.1016/j.nurt.2007.05.004] [Citation(s) in RCA: 230] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The ability to measure myelin in vivo has great consequences for furthering our knowledge of normal development, as well as for understanding a wide range of neurological disorders. The following review summarizes the current state of myelin imaging using MR. We consider five MR techniques that have been used to study myelin: 1) conventional MR, 2) MR spectroscopy, 3) diffusion, 4) magnetization transfer, and 5) T2 relaxation. Fundamental studies involving peripheral nerve and MR/histology comparisons have aided in the interpretation and validation of MR data. We highlight a number of important findings related to myelin development, damage, and repair, and we conclude with a critical summary of the current techniques available and their potential to image myelin in vivo.
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Affiliation(s)
- Cornelia Laule
- Department of Radiology, University of British Columbia, Vancouver, BC, V6T 2B5 Canada.
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Burman KJ, Palmer SM, Gamberini M, Spitzer MW, Rosa MG. Anatomical and physiological definition of the motor cortex of the marmoset monkey. J Comp Neurol 2007; 506:860-76. [DOI: 10.1002/cne.21580] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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