1
|
Yan H, Wang W, Cui T, Shao Y, Li M, Fang L, Feng L. Advances in the Understanding of the Correlation Between Neuroinflammation and Microglia in Alzheimer's Disease. Immunotargets Ther 2024; 13:287-304. [PMID: 38881647 PMCID: PMC11180466 DOI: 10.2147/itt.s455881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 06/05/2024] [Indexed: 06/18/2024] Open
Abstract
Alzheimer's disease (AD) is a fatal neurodegenerative disease with a subtle and progressive onset and is the most common type of dementia. However, its etiology and pathogenesis have not yet been fully elucidated. The common pathological manifestations of AD include extraneuronal β-amyloid deposition (Aβ), intraneuronal tau protein phosphorylation leading to the formation of 'neurofibrillary tangles' (NFTs), neuroinflammation, progressive loss of brain neurons/synapses, and glucose metabolism disorders. Current treatment approaches for AD primarily focus on the 'Aβ cascade hypothesis and abnormal aggregation of hyperphosphorylation of tau proteins', but have shown limited efficacy. Therefore, there is an ongoing need to identify more effective treatment targets for AD. The central nervous system (CNS) inflammatory response plays a key role in the occurrence and development of AD. Neuroinflammation is an immune response activated by glial cells in the CNS that usually occurs in response to stimuli such as nerve injury, infection and toxins or in response to autoimmunity. Neuroinflammation ranks as the third most prominent pathological feature in AD, following Aβ and NFTs. In recent years, the focus on the role of neuroinflammation and microglia in AD has increased due to the advancements in genome-wide association studies (GWAS) and sequencing technology. Furthermore, research has validated the pivotal role of microglia-mediated neuroinflammation in the progression of AD. Therefore, this article reviews the latest research progress on the role of neuroinflammation triggered by microglia in AD in recent years, aiming to provide a new theoretical basis for further exploring the role of neuroinflammation in the process of AD occurrence and development.
Collapse
Affiliation(s)
- Huiying Yan
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Wei Wang
- Department of Intensive Care Unit, The Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Tingting Cui
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Yanxin Shao
- Department of Neurology, The Second Affiliated Hospital of Shandong First Medical University, Taian, People's Republic of China
| | - Mingquan Li
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Limei Fang
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Lina Feng
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| |
Collapse
|
2
|
Boreland AJ, Stillitano AC, Lin HC, Abbo Y, Hart RP, Jiang P, Pang ZP, Rabson AB. Sustained type I interferon signaling after human immunodeficiency virus type 1 infection of human iPSC derived microglia and cerebral organoids. iScience 2024; 27:109628. [PMID: 38628961 PMCID: PMC11019286 DOI: 10.1016/j.isci.2024.109628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 02/01/2024] [Accepted: 03/26/2024] [Indexed: 04/19/2024] Open
Abstract
Human immunodeficiency virus type-1 (HIV-1)-associated neurocognitive disorder (HAND) affects up to half of people living with HIV-1 and causes long term neurological consequences. The pathophysiology of HIV-1-induced glial and neuronal functional deficits in humans remains enigmatic. To bridge this gap, we established a model simulating HIV-1 infection in the central nervous system using human induced pluripotent stem cell (iPSC)-derived microglia combined with sliced neocortical organoids. Incubation of microglia with two replication-competent macrophage-tropic HIV-1 strains (JRFL and YU2) elicited productive infection and inflammatory activation. RNA sequencing revealed significant and sustained activation of type I interferon signaling pathways. Incorporating microglia into sliced neocortical organoids extended the effects of aberrant type I interferon signaling in a human neural context. Collectively, our results illuminate a role for persistent type I interferon signaling in HIV-1-infected microglia in a human neural model, suggesting its potential significance in the pathogenesis of HAND.
Collapse
Affiliation(s)
- Andrew J. Boreland
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Alessandro C. Stillitano
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
| | - Hsin-Ching Lin
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
| | - Yara Abbo
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
| | - Ronald P. Hart
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
| | - Peng Jiang
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
| | - Zhiping P. Pang
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
- Department of Neuroscience and Cell Biology, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA
| | - Arnold B. Rabson
- Child Health Institute of New Jersey, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
- Departments of Pharmacology, Pathology & Laboratory Medicine, and Pediatrics, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
| |
Collapse
|
3
|
Nunes MJ, Carvalho AN, Rosa AI, Videira PA, Gama MJ, Rodrigues E, Castro-Caldas M. Altered expression of Sialyl Lewis X in experimental models of Parkinson's disease. J Mol Med (Berl) 2024; 102:365-377. [PMID: 38197965 PMCID: PMC10879467 DOI: 10.1007/s00109-023-02415-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 12/07/2023] [Accepted: 12/22/2023] [Indexed: 01/11/2024]
Abstract
The mechanisms underlying neurodegeneration in Parkinson's disease (PD) are still not fully understood. Glycosylation is an important post-translational modification that affects protein function, cell-cell contacts and inflammation and can be modified in pathologic conditions. Although the involvement of aberrant glycosylation has been proposed for PD, the knowledge of the diversity of glycans and their role in PD is still minimal. Sialyl Lewis X (sLeX) is a sialylated and fucosylated tetrasaccharide with essential roles in cell-to-cell recognition processes. Pathological conditions and pro-inflammatory mediators can up-regulate sLeX expression on cell surfaces, which has important consequences in intracellular signalling and immune function. Here, we investigated the expression of this glycan using in vivo and in vitro models of PD. We show the activation of deleterious glycation-related pathways in mouse striatum upon treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a toxin-based model of PD. Importantly, our results show that MPTP triggers the presentation of more proteins decorated with sLeX in mouse cortex and striatum in a time-dependent manner, as well as increased mRNA expression of its rate-limiting enzyme fucosyltransferase 7. sLeX is expressed in neurons, including dopaminergic neurons, and microglia. Although the underlying mechanism that drives increased sLeX epitopes, the nature of the protein scaffolds and their functional importance in PD remain unknown, our data suggest for the first time that sLeX in the brain may have a role in neuronal signalling and immunomodulation in pathological conditions. KEY MESSAGES: MPTP triggers the presentation of proteins decorated with sLeX in mouse brain. MPTP triggers the expression of sLeX rate-limiting enzyme FUT 7 in striatum. sLeX is expressed in neurons, including dopaminergic neurons, and microglia. sLeX in the brain may have a role in neuronal signalling and immunomodulation.
Collapse
Affiliation(s)
- Maria João Nunes
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisbon, Portugal
| | - Andreia Neves Carvalho
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisbon, Portugal
| | - Alexandra I Rosa
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisbon, Portugal
| | - Paula A Videira
- Department of Life Sciences, UCIBIO, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal.
- CDG & Allies - Professionals and Patient Associations International Network (CDG & Allies - PPAIN), NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal.
| | - Maria João Gama
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisbon, Portugal
| | - Elsa Rodrigues
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisbon, Portugal
| | - Margarida Castro-Caldas
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003, Lisbon, Portugal.
- Department of Life Sciences, UCIBIO, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal.
| |
Collapse
|
4
|
Zhang X, Wang X, Xu Z, Sun F, Jia Y, Tian Y. Siglec-E Ligand Downregulation on Hippocampus Neurons Induced Inflammation in Sevoflurane-Associated Perioperative Neurocognitive Disorders in Aged Mice. Inflammation 2024; 47:30-44. [PMID: 37603227 DOI: 10.1007/s10753-023-01888-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/05/2023] [Accepted: 08/11/2023] [Indexed: 08/22/2023]
Abstract
Activated microglia-induced inflammation in the hippocampus plays an important role in perioperative neurocognitive disorders. Previous studies have shown that sialic acid-binding immunoglobulin-like lectin 3 (hSiglec-3, ortholog of mouse Siglec-E) engagement in microglia and its glycan ligands on neurons contributes to inflammatory homeostasis through an endogenous negative regulation pathway. This study aimed to explore whether the glycan ligand alteration on neurons plays a role in sevoflurane-induced perioperative neurocognitive disorders. This study's data has shown that a slight Siglec-E ligands' expression decrease does not induce inflammation homeostasis disruption. We also demonstrated that the ligand level on neurons was decreased with age, and the reduced Siglec-E ligand expression on neurons caused via sevoflurane was induced by neuraminidase 1. Furthermore, this study has shown that the Siglec-E ligand expression decline caused by age and sevoflurane treatment could decrease the ligands' level, thus leading to inflammatory homeostasis disruption. This research provided a novel mechanism for perioperative neurocognitive disorder susceptibility in the elderly.
Collapse
Affiliation(s)
- Xiaoli Zhang
- Department of Critical Care Medicine, Shengjing Hospital of China Medical University, Shenyang, Liaoning, 110004, China
| | - Xueting Wang
- Department of Anesthesiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, Liaoning, 110004, China
| | - Ziyang Xu
- Department of Anesthesiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, Liaoning, 110004, China
| | - Fengwei Sun
- Department of Anesthesiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, Liaoning, 110004, China
| | - Yi Jia
- Institute of Materia Medica and Department of Pharmaceutics, College of Pharmacy, Army Medical University, Chongqing, 400038, China
| | - Yue Tian
- Department of Anesthesiology, Shengjing Hospital of China Medical University, 36 Sanhao Street, Heping District, Shenyang, Liaoning, 110004, China.
| |
Collapse
|
5
|
Bocharova O, Makarava N, Pandit NP, Molesworth K, Baskakov IV. Multiple steps of prion strain adaptation to a new host. Front Neurosci 2024; 18:1329010. [PMID: 38362022 PMCID: PMC10867973 DOI: 10.3389/fnins.2024.1329010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/12/2024] [Indexed: 02/17/2024] Open
Abstract
The transmission of prions across species is a critical aspect of their dissemination among mammalian hosts, including humans. This process often necessitates strain adaptation. In this study, we sought to investigate the mechanisms underlying prion adaptation while mitigating biases associated with the history of cross-species transmission of natural prion strains. To achieve this, we utilized the synthetic hamster prion strain S05. Propagation of S05 using mouse PrPC in Protein Misfolding Cyclic Amplification did not immediately overcome the species barrier. This finding underscores the involvement of factors beyond disparities in primary protein structures. Subsequently, we performed five serial passages to stabilize the incubation time to disease in mice. The levels of PrPSc increased with each passage, reaching a maximum at the third passage, and declining thereafter. This suggests that only the initial stage of adaptation is primarily driven by an acceleration in PrPSc replication. During the protracted adaptation to a new host, we observed significant alterations in the glycoform ratio and sialylation status of PrPSc N-glycans. These changes support the notion that qualitative modifications in PrPSc contribute to a more rapid disease progression. Furthermore, consistent with the decline in sialylation, a cue for "eat me" signaling, the newly adapted strain exhibited preferential colocalization with microglia. In contrast to PrPSc dynamics, the intensity of microglia activation continued to increase after the third passage in the new host. In summary, our study elucidates that the adaptation of a prion strain to a new host is a multi-step process driven by several factors.
Collapse
Affiliation(s)
- Olga Bocharova
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Narayan P. Pandit
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Kara Molesworth
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Ilia V. Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, MD, United States
| |
Collapse
|
6
|
Kolesov D, Astakhova A, Galdobina M, Moskovtsev A, Kubatiev A, Sokolovskaya A, Ukrainskiy L, Morozov S. Scanning Probe Microscopy Techniques for Studying the Cell Glycocalyx. Cells 2023; 12:2778. [PMID: 38132098 PMCID: PMC10741541 DOI: 10.3390/cells12242778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/01/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023] Open
Abstract
The glycocalyx is a brush-like layer that covers the surfaces of the membranes of most cell types. It consists of a mixture of carbohydrates, mainly glycoproteins and proteoglycans. Due to its structure and sensitivity to environmental conditions, it represents a complicated object to investigate. Here, we review studies of the glycocalyx conducted using scanning probe microscopy approaches. This includes imaging techniques as well as the measurement of nanomechanical properties. The nanomechanics of the glycocalyx is particularly important since it is widely present on the surfaces of mechanosensitive cells such as endothelial cells. An overview of problems with the interpretation of indirect data via the use of analytical models is presented. Special insight is given into changes in glycocalyx properties during pathological processes. The biological background and alternative research methods are briefly covered.
Collapse
Affiliation(s)
- Dmitry Kolesov
- Moscow Polytechnic University, 107023 Moscow, Russia
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
| | - Anna Astakhova
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
| | - Maria Galdobina
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
| | - Alexey Moskovtsev
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
| | - Aslan Kubatiev
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
| | - Alisa Sokolovskaya
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
| | - Leonid Ukrainskiy
- Mechanical Engineering Research Institute of the Russian Academy of Sciences, 119334 Moscow, Russia
| | - Sergey Morozov
- Institute of General Pathology and Pathophysiology, 125315 Moscow, Russia
| |
Collapse
|
7
|
Bocharova O, Makarava N, Pandit NP, Molesworth K, Baskakov IV. Multiple steps of prion strain adaptation to a new host. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.24.563743. [PMID: 37961127 PMCID: PMC10634783 DOI: 10.1101/2023.10.24.563743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The transmission of prions across species is a critical aspect of their dissemination among mammalian hosts, including humans. This process often necessitates strain adaptation. In this study, we sought to investigate the mechanisms underlying prion adaptation while mitigating biases associated with the history of cross-species transmission of natural prion strains. To achieve this, we utilized the synthetic hamster prion strain S05. Propagation of S05 using mouse PrPC in Protein Misfolding Cyclic Amplification did not immediately overcome the species barrier. This finding underscores the involvement of factors beyond disparities in primary protein structures. Subsequently, we performed five serial passages to stabilize the incubation time to disease in mice. The levels of PrPSc increased with each passage, reaching a maximum at the third passage, and declining thereafter. This suggests that only the initial stage of adaptation is primarily driven by an acceleration in PrPSc replication. During the protracted adaptation to a new host, we observed significant alterations in the glycoform ratio and sialylation status of PrPSc N-glycans. These changes support the notion that qualitative modifications in PrPSc contribute to a more rapid disease progression. Furthermore, consistent with the decline in sialylation, a cue for "eat me" signaling, the newly adapted strain exhibited preferential colocalization with microglia. In contrast to PrPSc dynamics, the intensity of microglia activation continued to increase after the third passage in the new host. In summary, our study elucidates that the adaptation of a prion strain to a new host is a multi-step process driven by several factors.
Collapse
Affiliation(s)
- Olga Bocharova
- Center for Biomedical Engineering and Technology, Baltimore, Maryland, USA
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology, Baltimore, Maryland, USA
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Narayan P. Pandit
- Center for Biomedical Engineering and Technology, Baltimore, Maryland, USA
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Kara Molesworth
- Center for Biomedical Engineering and Technology, Baltimore, Maryland, USA
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Ilia V. Baskakov
- Center for Biomedical Engineering and Technology, Baltimore, Maryland, USA
- Department of Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
8
|
CD33 isoforms in microglia and Alzheimer's disease: Friend and foe. Mol Aspects Med 2023; 90:101111. [PMID: 35940942 DOI: 10.1016/j.mam.2022.101111] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/18/2022] [Accepted: 07/27/2022] [Indexed: 02/08/2023]
Abstract
Alzheimer's disease (AD) is the most common form of neurodegenerative disease and is considered the main cause of dementia worldwide. Genome-wide association studies combined with integrated analysis of functional datasets support a critical role for microglia in AD pathogenesis, identifying them as important potential therapeutic targets. The ability of immunomodulatory receptors on microglia to control the response to pathogenic amyloid-β aggregates has gained significant interest. Siglec-3, also known as CD33, is one of these immunomodulatory receptors expressed on microglia that has been identified as an AD susceptibility factor. Here, we review recent advances made in understanding the multifaceted roles that CD33 plays in microglia with emphasis on two human-specific CD33 isoforms that differentially correlate with AD susceptibility. We also describe several different therapeutic approaches for targeting CD33 that have been advanced for the purpose of skewing microglial cell responses.
Collapse
|
9
|
Makarava N, Baskakov IV. Role of sialylation of N-linked glycans in prion pathogenesis. Cell Tissue Res 2023; 392:201-214. [PMID: 35088180 PMCID: PMC9329487 DOI: 10.1007/s00441-022-03584-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 01/12/2022] [Indexed: 01/10/2023]
Abstract
Mammalian prion or PrPSc is a proteinaceous infectious agent that consists of a misfolded, self-replicating state of the prion protein or PrPC. PrPC and PrPSc are posttranslationally modified with N-linked glycans, which are sialylated at the terminal positions. More than 30 years have passed since the first characterization of the composition and structural diversity of N-linked glycans associated with the prion protein, yet the role of carbohydrate groups that constitute N-glycans and, in particular, their terminal sialic acid residues in prion disease pathogenesis remains poorly understood. A number of recent studies shed a light on the role of sialylation in the biology of prion diseases. This review article discusses several mechanisms by which terminal sialylation dictates the spread of PrPSc across brain regions and the outcomes of prion infection in an organism. In particular, relationships between the sialylation status of PrPSc and important strain-specific features including lymphotropism, neurotropism, and neuroinflammation are discussed. Moreover, emerging evidence pointing out the roles of sialic acid residues in prion replication, cross-species transmission, strain competition, and strain adaptation are reviewed. A hypothesis according to which selective, strain-specified recruitment of PrPC sialoglycoforms dictates unique strain-specific disease phenotypes is examined. Finally, the current article proposes that prion strains evolve as a result of a delicate balance between recruiting highly sialylated glycoforms to avoid an "eat-me" response by glia and limiting heavily sialylated glycoforms for enabling rapid prion replication.
Collapse
Affiliation(s)
- Natallia Makarava
- Center for Biomedical Engineering and Technology and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Ilia V Baskakov
- Center for Biomedical Engineering and Technology and Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
| |
Collapse
|
10
|
Schnaar RL. Gangliosides as Siglec ligands. Glycoconj J 2023; 40:159-167. [PMID: 36701102 PMCID: PMC11000168 DOI: 10.1007/s10719-023-10101-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/09/2023] [Accepted: 01/13/2023] [Indexed: 01/27/2023]
Abstract
The structure of a sialoglycan can be translated into to a biological response when it binds to a specific endogenous lectin. Among endogenous sialic acid-binding lectins in humans are those comprising the 15-member Siglec family, most of which are expressed on overlapping sets of immune cells. Endogenous Siglec ligands are sialoglycolipids (gangliosides) and/or sialoglycoproteins, on cell surfaces or in the extracellular milieu, that bind to and initiate signaling by cell surface Siglecs. In the nervous system, where gangliosides are the predominant sialoglycans, Siglec-4 (myelin-associated glycoprotein) on myelinating cells binds to gangliosides GD1a and GT1b on nerve cell axons to ensure stable and productive axon-myelin interactions. In the immune system, Siglec-7 on natural killer cells binds to gangliosides GD3 and GD2 to inhibit immune signaling. Expression of GD3 and GD2 on cancer cells can lead to tumor immune evasion. Siglec-1 (sialoadhesin, CD169) on macrophages binds to gangliosides on tumors and enveloped viruses. This may enhance antigen presentation in some cases, or increase viral distribution in others. Several other Siglecs bind to gangliosides in vitro, the biological significance of which has yet to be fully established. Gangliosides, which are found on all human cells and tissues in cell-specific distributions, are functional Siglec ligands with varied roles driving Siglec-mediated signaling.
Collapse
Affiliation(s)
- Ronald L Schnaar
- Department of Pharmacology and Molecular Sciences, Department of Neuroscience, Johns Hopkins University School of Medicine, 725 N Wolfe St, Baltimore, MD, 21205, USA.
| |
Collapse
|
11
|
Microglial Activation in Metal Neurotoxicity: Impact in Neurodegenerative Diseases. BIOMED RESEARCH INTERNATIONAL 2023; 2023:7389508. [PMID: 36760476 PMCID: PMC9904912 DOI: 10.1155/2023/7389508] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/18/2023] [Accepted: 01/23/2023] [Indexed: 02/04/2023]
Abstract
Neurodegenerative processes encompass a large variety of diseases with different pathological patterns and clinical features, such as Alzheimer's and Parkinson's diseases. Exposure to metals has been hypothesized to increase oxidative stress in brain cells leading to cell death and neurodegeneration. Neurotoxicity of metals has been demonstrated by several in vitro and in vivo experimental studies, and most probably, each metal has its specific pathway to trigger cell death. As a result, exposure to essential metals, such as manganese, iron, copper, zinc, and cobalt, and nonessential metals, including lead, aluminum, and cadmium, perturbs metal homeostasis at the cellular and organism levels leading to neurodegeneration. In this contribution, a comprehensive review of the molecular mechanisms by which metals affect microglia physiology and signaling properties is presented. Furthermore, studies that validate the disruption of microglia activation pathways as an essential mechanism of metal toxicity that can contribute to neurodegenerative disease are also presented and discussed.
Collapse
|
12
|
Salminen A, Kaarniranta K, Kauppinen A. Hypoxia/ischemia impairs CD33 (Siglec-3)/TREM2 signaling: Potential role in Alzheimer's pathogenesis. Neurochem Int 2021; 150:105186. [PMID: 34530055 DOI: 10.1016/j.neuint.2021.105186] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/10/2021] [Accepted: 09/12/2021] [Indexed: 12/22/2022]
Abstract
Recent genetic and molecular studies have indicated that the innate immune system, especially microglia, have a crucial role in the accumulation of β-amyloid plaques in Alzheimer's disease (AD). In particular, the CD33 receptor, also called Siglec-3, inhibits the TREM2 receptor-induced phagocytic activity of microglia. CD33 receptors recognize the α2,3 and α2,6-linked sialic groups in tissue glycocalyx, especially sialylated gangliosides in human brain. The CD33 receptor triggers cell-type specific responses, e.g., in microglia, CD33 inhibits phagocytosis, whereas in natural killer cells, it inhibits the cytotoxic activity of the NKG2D receptor. Nonetheless, the regulation of the activity of CD33 receptor needs to be clarified. For example, it seems that hypoxia/ischemia, a potential cause of AD pathology, increases the expression of CD33 and its downstream target SHP-1, a tyrosine phosphatase which suppresses the phagocytosis driven by TREM2. Moreover, hypoxia/ischemia increases the deposition of sialylated gangliosides, e.g., GM1, GM2, GM3, and GD1, which are ligands for inhibitory CD33/Siglec-3 receptors. In addition, β-amyloid peptides bind to the sialylated gangliosides in raft-like clusters and subsequently these gangliosides act as seeds for the formation of β-amyloid plaques in AD pathology. It is known that senile plaques contain sialylated GM1, GM2, and GM3 gangliosides, i.e., the same species induced by hypoxia/ischemia treatment. Sialylated gangliosides in plaques might stimulate the CD33/Siglec-3 receptors of microglia and thus impede TREM2-driven phagocytosis. We propose that hypoxia/ischemia, e.g., via the accumulation of sialylated gangliosides, prevents the phagocytosis of β-amyloid deposits by inhibiting CD33/TREM2 signaling.
Collapse
Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland.
| | - Kai Kaarniranta
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, P.O. Box 100, FI-70029, KYS, Finland
| | - Anu Kauppinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| |
Collapse
|
13
|
Abstract
PURPOSE OF REVIEW The aim of this study was to provide an update on the role of the innate immune system and neuroinflammation in the pathogenesis of Alzheimer's disease, with an emphasis on microglial receptors CD33 and TREM2. RECENT FINDINGS Genome-wide association studies (GWAS) have identified many Alzheimer's disease risk genes related to immune response and microglia including the phagocytic receptors CD33 and TREM2. Recent GWAS and pathway analyses emphasize the crucial role of the innate immune system and neuroinflammation in the pathogenesis of Alzheimer's disease. Disease-associated microglia have been characterized by TREM2-dependent upregulation of phagocytic and lipid metabolism genes. Impaired microglial phagocytosis results in amyloid beta (Aβ) accumulation leading to neuroinflammation that is the primary cause of neurodegeneration. CD33 and TREM2 modulate neuroinflammation in Alzheimer's disease and have emerged as therapeutic targets in Alzheimer's disease. Progress has been made to inhibit CD33 by gene therapy, small molecules or immunotherapy, and to increase TREM2 activity by immunotherapy. Finally, mAbs against CD33 and TREM2 have entered clinical trials and may reduce neuroinflammation in Alzheimer's disease brain. SUMMARY Targeting neuroinflammation via CD33 inhibition and/or TREM2 activation may have important implications for neurodegeneration in Alzheimer's disease and may be an addition to monoclonal anti-Aβ antibody treatments that remove plaques without reducing neuroinflammation.
Collapse
Affiliation(s)
- Ana Griciuc
- Genetics and Aging Research Unit, McCance Center for Brain Health, Mass General Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA
| | | |
Collapse
|
14
|
Läubli H, Kawanishi K, George Vazhappilly C, Matar R, Merheb M, Sarwar Siddiqui S. Tools to study and target the Siglec-sialic acid axis in cancer. FEBS J 2020; 288:6206-6225. [PMID: 33251699 DOI: 10.1111/febs.15647] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/18/2020] [Accepted: 11/23/2020] [Indexed: 12/16/2022]
Abstract
Siglecs are widely expressed on leucocytes and bind to ubiquitously presented glycans containing sialic acids (sialoglycans). Most Siglecs carry an immunoreceptor tyrosine-based inhibition motif (ITIM) and elicit an inhibitory intracellular signal upon ligand binding. A few Siglec receptors can, however, recruit immunoreceptor tyrosine-based activation motif (ITAM)-containing factors, which activate cells. The role of hypersialylation (the enhanced expression of sialoglycans) has recently been explored in cancer progression. Mechanistic studies have shown that hypersialylation on cancer cells can engage inhibitory Siglecs on the surface of immune cells and induce immunosuppression. These recent studies strongly suggest that the Siglec-sialic acid axis can act as a potential target for cancer immunotherapy. Moreover, the use of new tools and techniques is facilitating these studies. In this review, we summarise techniques used to study Siglecs, including different mouse models, monoclonal antibodies, Siglec fusion proteins, and sialoglycan arrays. Furthermore, we discuss the recent major developments in the study of Siglecs in cancer immunosuppression, tools, and techniques used in targeting the Siglec-sialic acid axis and the possibility of clinical intervention.
Collapse
Affiliation(s)
- Heinz Läubli
- Laboratory for Cancer Immunotherapy, Department of Biomedicine, and Medical Oncology, Department of Internal Medicine, University Hospital Basel, Switzerland
| | - Kunio Kawanishi
- Kidney and Vascular Pathology, University of Tsukuba, Ibaraki, Japan
| | | | - Rachel Matar
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), UAE
| | - Maxime Merheb
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), UAE
| | | |
Collapse
|
15
|
Baskakov IV. Role of sialylation in prion disease pathogenesis and prion structure. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2020; 175:31-52. [PMID: 32958238 DOI: 10.1016/bs.pmbts.2020.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mammalian prion or PrPSc is a proteinaceous infectious agent that consists of a misfolded, self-replicating state of a sialoglycoprotein called the prion protein or PrPC. Sialylation of the prion protein, a terminal modification of N-linked glycans, was discovered more than 30 years ago, yet the role of sialylation in prion pathogenesis is not well understood. This chapter summarizes current knowledge on the role of sialylation of the prion protein in prion diseases. First, we discuss recent data suggesting that sialylation of PrPSc N-linked glycans determines the fate of prion infection in an organism and control prion lymphotropism. Second, emerging evidence pointing out at the role N-glycans in neuroinflammation are discussed. Thirds, this chapter reviews a mechanism postulating that sialylated N-linked glycans are important players in defining strain-specific structures. A new hypothesis according to which individual strain-specific PrPSc structures govern selection of PrPC sialoglycoforms is discussed. Finally, this chapter explain how N-glycan sialylation control the prion replication and strain interference. In summary, comprehensive review of our knowledge on N-linked glycans and their sialylation provided in this chapter helps to answer important questions of prion biology that have been puzzling for years.
Collapse
Affiliation(s)
- Ilia V Baskakov
- Department of Anatomy and Neurobiology, and Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, United States.
| |
Collapse
|
16
|
Makarava N, Chang JCY, Molesworth K, Baskakov IV. Posttranslational modifications define course of prion strain adaptation and disease phenotype. J Clin Invest 2020; 130:4382-4395. [PMID: 32484800 PMCID: PMC7410085 DOI: 10.1172/jci138677] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/13/2020] [Indexed: 12/13/2022] Open
Abstract
Posttranslational modifications are a common feature of proteins associated with neurodegenerative diseases including prion protein (PrPC), tau, and α-synuclein. Alternative self-propagating protein states or strains give rise to different disease phenotypes and display strain-specific subsets of posttranslational modifications. The relationships between strain-specific structure, posttranslational modifications, and disease phenotype are poorly understood. We previously reported that among hundreds of PrPC sialoglycoforms expressed by a cell, individual prion strains recruited PrPC molecules selectively, according to the sialylation status of their N-linked glycans. Here we report that transmission of a prion strain to a new host is accompanied by a dramatic shift in the selectivity of recruitment of PrPC sialoglycoforms, giving rise to a self-propagating scrapie isoform (PrPSc) with a unique sialoglycoform signature and disease phenotype. The newly emerged strain has the shortest incubation time to disease and is characterized by colocalization of PrPSc with microglia and a very profound proinflammatory response, features that are linked to a unique sialoglycoform composition of PrPSc. The current work provides experimental support for the hypothesis that strain-specific patterns of PrPSc sialoglycoforms formed as a result of selective recruitment dictate strain-specific disease phenotypes. This work suggests a causative relationship between a strain-specific structure, posttranslational modifications, and disease phenotype.
Collapse
Affiliation(s)
- Natallia Makarava
- Center for Biomedical Engineering and Technology and
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jennifer Chen-Yu Chang
- Center for Biomedical Engineering and Technology and
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Kara Molesworth
- Center for Biomedical Engineering and Technology and
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Ilia V. Baskakov
- Center for Biomedical Engineering and Technology and
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| |
Collapse
|
17
|
Makarava N, Chang JCY, Baskakov IV. Region-Specific Sialylation Pattern of Prion Strains Provides Novel Insight into Prion Neurotropism. Int J Mol Sci 2020; 21:ijms21030828. [PMID: 32012886 PMCID: PMC7037812 DOI: 10.3390/ijms21030828] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/10/2020] [Accepted: 01/23/2020] [Indexed: 12/14/2022] Open
Abstract
Mammalian prions are unconventional infectious agents that invade and replicate in an organism by recruiting a normal form of a prion protein (PrPC) and converting it into misfolded, disease-associated state referred to as PrPSc. PrPC is posttranslationally modified with two N-linked glycans. Prion strains replicate by selecting substrates from a large pool of PrPC sialoglycoforms expressed by a host. Brain regions have different vulnerability to prion infection, however, molecular mechanisms underlying selective vulnerability is not well understood. Toward addressing this question, the current study looked into a possibility that sialylation of PrPSc might be involved in defining selective vulnerability of brain regions. The current work found that in 22L -infected animals, PrPSc is indeed sialylated in a region dependent manner. PrPSc in hippocampus and cortex was more sialylated than PrPSc from thalamus and stem. Similar trends were also observed in brain materials from RML- and ME7-infected animals. The current study established that PrPSc sialylation status is indeed region-specific. Together with previous studies demonstrating that low sialylation status accelerates prion replication, this work suggests that high vulnerability of certain brain region to prion infection could be attributed to their low sialylation status.
Collapse
Affiliation(s)
- Natallia Makarava
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.M.); (J.C.-Y.C.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Jennifer Chen-Yu Chang
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.M.); (J.C.-Y.C.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Ilia V. Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (N.M.); (J.C.-Y.C.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
- Correspondence:
| |
Collapse
|
18
|
Klaus C, Hansen JN, Ginolhac A, Gérard D, Gnanapragassam VS, Horstkorte R, Rossdam C, Buettner FFR, Sauter T, Sinkkonen L, Neumann H, Linnartz-Gerlach B. Reduced sialylation triggers homeostatic synapse and neuronal loss in middle-aged mice. Neurobiol Aging 2020; 88:91-107. [PMID: 32087947 DOI: 10.1016/j.neurobiolaging.2020.01.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/06/2020] [Accepted: 01/14/2020] [Indexed: 12/21/2022]
Abstract
Sialic acid-binding Ig-like lectin (Siglec) receptors are linked to neurodegenerative processes, but the role of sialic acids in physiological aging is still not fully understood. We investigated the impact of reduced sialylation in the brain of mice heterozygous for the enzyme glucosamine-2-epimerase/N-acetylmannosamine kinase (GNE+/-) that is essential for sialic acid biosynthesis. We demonstrate that GNE+/- mice have hyposialylation in different brain regions, less synapses in the hippocampus and reduced microglial arborization already at 6 months followed by increased loss of neurons at 12 months. A transcriptomic analysis revealed no pro-inflammatory changes indicating an innate homeostatic immune process leading to the removal of synapses and neurons in GNE+/- mice during aging. Crossbreeding with complement C3-deficient mice rescued the earlier onset of neuronal and synaptic loss as well as the changes in microglial arborization. Thus, sialic acids of the glycocalyx contribute to brain homeostasis and act as a recognition system for the innate immune system in the brain.
Collapse
Affiliation(s)
- Christine Klaus
- Neural Regeneration, Institute of Reconstructive Neurobiology, Medical Faculty and University Hospital of Bonn, University of Bonn, Bonn, Germany
| | - Jan N Hansen
- Biophysical Imaging, Institute of Innate Immunity, Medical Faculty, University of Bonn, Bonn, Germany
| | - Aurélien Ginolhac
- Epigenetics Team, Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Belvaux, Luxembourg
| | - Deborah Gérard
- Epigenetics Team, Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Belvaux, Luxembourg
| | - Vinayaga S Gnanapragassam
- Institute for Physiological Chemistry, Medical Faculty, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Rüdiger Horstkorte
- Institute for Physiological Chemistry, Medical Faculty, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Charlotte Rossdam
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Falk F R Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Thomas Sauter
- Epigenetics Team, Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Belvaux, Luxembourg
| | - Lasse Sinkkonen
- Epigenetics Team, Systems Biology Group, Life Sciences Research Unit, University of Luxembourg, Belvaux, Luxembourg
| | - Harald Neumann
- Neural Regeneration, Institute of Reconstructive Neurobiology, Medical Faculty and University Hospital of Bonn, University of Bonn, Bonn, Germany.
| | - Bettina Linnartz-Gerlach
- Neural Regeneration, Institute of Reconstructive Neurobiology, Medical Faculty and University Hospital of Bonn, University of Bonn, Bonn, Germany
| |
Collapse
|
19
|
Siddiqui SS, Matar R, Merheb M, Hodeify R, Vazhappilly CG, Marton J, Shamsuddin SA, Al Zouabi H. Siglecs in Brain Function and Neurological Disorders. Cells 2019; 8:E1125. [PMID: 31546700 PMCID: PMC6829431 DOI: 10.3390/cells8101125] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 12/14/2022] Open
Abstract
Siglecs (Sialic acid-binding immunoglobulin-type lectins) are a I-type lectin that typically binds sialic acid. Siglecs are predominantly expressed in immune cells and generate activating or inhibitory signals. They are also shown to be expressed on the surface of cells in the nervous system and have been shown to play central roles in neuroinflammation. There has been a plethora of reviews outlining the studies pertaining to Siglecs in immune cells. However, this review aims to compile the articles on the role of Siglecs in brain function and neurological disorders. In humans, the most abundant Siglecs are CD33 (Siglec-3), Siglec-4 (myelin-associated glycoprotein/MAG), and Siglec-11, Whereas in mice the most abundant are Siglec-1 (sialoadhesin), Siglec-2 (CD22), Siglec-E, Siglec-F, and Siglec-H. This review is divided into three parts. Firstly, we discuss the general biological aspects of Siglecs that are expressed in nervous tissue. Secondly, we discuss about the role of Siglecs in brain function and molecular mechanism for their function. Finally, we collate the available information on Siglecs and neurological disorders. It is intriguing to study this family of proteins in neurological disorders because they carry immunoinhibitory and immunoactivating motifs that can be vital in neuroinflammation.
Collapse
Affiliation(s)
- Shoib Sarwar Siddiqui
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), Ras Al Khaimah 10021, UAE.
| | - Rachel Matar
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), Ras Al Khaimah 10021, UAE.
| | - Maxime Merheb
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), Ras Al Khaimah 10021, UAE.
| | - Rawad Hodeify
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), Ras Al Khaimah 10021, UAE.
| | - Cijo George Vazhappilly
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), Ras Al Khaimah 10021, UAE.
| | - John Marton
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), Ras Al Khaimah 10021, UAE.
| | | | - Hussain Al Zouabi
- Department of Biotechnology, American University of Ras Al Khaimah (AURAK), Ras Al Khaimah 10021, UAE.
| |
Collapse
|
20
|
Rashid K, Akhtar-Schaefer I, Langmann T. Microglia in Retinal Degeneration. Front Immunol 2019; 10:1975. [PMID: 31481963 PMCID: PMC6710350 DOI: 10.3389/fimmu.2019.01975] [Citation(s) in RCA: 200] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 08/05/2019] [Indexed: 12/18/2022] Open
Abstract
The retina is a complex tissue with multiple cell layers that are highly ordered. Its sophisticated structure makes it especially sensitive to external or internal perturbations that exceed the homeostatic range. This necessitates the continuous surveillance of the retina for the detection of noxious stimuli. This task is mainly performed by microglia cells, the resident tissue macrophages which confer neuroprotection against transient pathophysiological insults. However, under sustained pathological stimuli, microglial inflammatory responses become dysregulated, often worsening disease pathology. In this review, we provide an overview of recent studies that depict microglial responses in diverse retinal pathologies that have degeneration and chronic immune reactions as key pathophysiological components. We also discuss innovative immunomodulatory therapy strategies that dampen the detrimental immunological responses to improve disease outcome.
Collapse
Affiliation(s)
- Khalid Rashid
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Isha Akhtar-Schaefer
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Thomas Langmann
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, Cologne, Germany
| |
Collapse
|
21
|
Akhtar-Schäfer I, Wang L, Krohne TU, Xu H, Langmann T. Modulation of three key innate immune pathways for the most common retinal degenerative diseases. EMBO Mol Med 2019; 10:emmm.201708259. [PMID: 30224384 PMCID: PMC6180304 DOI: 10.15252/emmm.201708259] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
This review highlights the role of three key immune pathways in the pathophysiology of major retinal degenerative diseases including diabetic retinopathy, age‐related macular degeneration, and rare retinal dystrophies. We first discuss the mechanisms how loss of retinal homeostasis evokes an unbalanced retinal immune reaction involving responses of local microglia and recruited macrophages, activity of the alternative complement system, and inflammasome assembly in the retinal pigment epithelium. Presenting these key mechanisms as complementary targets, we specifically emphasize the concept of immunomodulation as potential treatment strategy to prevent or delay vision loss. Promising molecules are ligands for phagocyte receptors, specific inhibitors of complement activation products, and inflammasome inhibitors. We comprehensively summarize the scientific evidence for this strategy from preclinical animal models, human ocular tissue analyses, and clinical trials evolving in the last few years.
Collapse
Affiliation(s)
- Isha Akhtar-Schäfer
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Luping Wang
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Tim U Krohne
- Department of Ophthalmology, University of Bonn, Bonn, Germany
| | - Heping Xu
- Centre for Experimental Medicine, The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry & Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Thomas Langmann
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, University of Cologne, Cologne, Germany .,Center for Molecular Medicine, University of Cologne, Cologne, Germany
| |
Collapse
|
22
|
Willems AP, Sun L, Schulz MA, Tian W, Ashikov A, van Scherpenzeel M, Hermans E, Clausen H, Yang Z, Lefeber DJ. Activity of N-acylneuraminate-9-phosphatase (NANP) is not essential for de novo sialic acid biosynthesis. Biochim Biophys Acta Gen Subj 2019; 1863:1471-1479. [PMID: 31121216 DOI: 10.1016/j.bbagen.2019.05.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/20/2019] [Accepted: 05/17/2019] [Indexed: 12/30/2022]
Abstract
BACKGROUND Sialylation of glycoproteins and glycolipids is important for biological processes such as cellular communication, cell migration and protein function. Biosynthesis of CMP-sialic acid, the essential substrate, comprises five enzymatic steps, involving ManNAc and sialic acid and their phosphorylated forms as intermediates. Genetic diseases in this pathway result in different and tissue-restricted phenotypes, which is poorly understood. METHODS AND RESULTS We aimed to study the mechanisms of sialic acid metabolism in knockouts (KO) of the sialic acid pathway in two independent cell lines. Sialylation of cell surface glycans was reduced by KO of GNE (UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase), NANS (sialic acid synthase) and CMAS (N-acylneuraminate cytidylyltransferase) genes, but was largely unaffected in NANP (N-acylneuraminate-9-phosphatase) KO, as studied by MAA and PNA lectin binding. NANP is the third enzyme in sialic acid biosynthesis and dephosphorylates sialic acid 9-phosphate to free sialic acid. LC-MS analysis of sialic acid metabolites showed that CMP-sialic acid was dramatically reduced in GNE and NANS KO cells and undetectable in CMAS KO. In agreement with normal cell surface sialylation, CMP-sialic acid levels in NANP KO were comparable to WT cells, even though sialic acid 9-phosphate, the substrate of NANP accumulated. Metabolic flux analysis with 13C6-labelled ManNAc showed a lower, but significant conversion of ManNAc into sialic acid. CONCLUSIONS Our data provide evidence that NANP activity is not essential for de novo sialic acid production and point towards an alternative phosphatase activity, bypassing NANP. GENERAL SIGNIFICANCE This report contributes to a better understanding of sialic acid biosynthesis in humans.
Collapse
Affiliation(s)
- Anke P Willems
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Lingbo Sun
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Morten Alder Schulz
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Weihua Tian
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Angel Ashikov
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Monique van Scherpenzeel
- Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Esther Hermans
- Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Zhang Yang
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Dirk J Lefeber
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands; Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525, GA, Nijmegen, the Netherlands.
| |
Collapse
|
23
|
Melrose J. Functional Consequences of Keratan Sulfate Sulfation in Electrosensory Tissues and in Neuronal Regulation. ACTA ACUST UNITED AC 2019; 3:e1800327. [PMID: 32627425 DOI: 10.1002/adbi.201800327] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/16/2019] [Indexed: 12/20/2022]
Abstract
Keratan sulfate (KS) is a functional electrosensory and neuro-instructive molecule. Recent studies have identified novel low sulfation KS in auditory and sensory tissues such as the tectorial membrane of the organ of Corti and the Ampullae of Lorenzini in elasmobranch fish. These are extremely sensitive proton gradient detection systems that send signals to neural interfaces to facilitate audition and electrolocation. High and low sulfation KS have differential functional roles in song learning in the immature male zebra song-finch with high charge density KS in song nuclei promoting brain development and cognitive learning. The conductive properties of KS are relevant to the excitable neural phenotype. High sulfation KS interacts with a large number of guidance and neuroregulatory proteins. The KS proteoglycan microtubule associated protein-1B (MAP1B) stabilizes actin and tubulin cytoskeletal development during neuritogenesis. A second 12 span transmembrane synaptic vesicle associated KS proteoglycan (SV2) provides a smart gel storage matrix for the storage of neurotransmitters. MAP1B and SV2 have prominent roles to play in neuroregulation. Aggrecan and phosphacan have roles in perineuronal net formation and in neuroregulation. A greater understanding of the biology of KS may be insightful as to how neural repair might be improved.
Collapse
Affiliation(s)
- James Melrose
- Raymond Purves Bone and Joint Research Laboratories, Kolling Institute of Medical Research, Royal North Shore Hospital and University of Sydney, St. Leonards, NSW, 2065, Australia.,Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, 2052, Australia.,Sydney Medical School, Northern, Sydney University, Royal North Shore Hospital, St. Leonards, NSW, 2065, Australia.,Faculty of Medicine and Health, University of Sydney, Royal North Shore Hospital, St. Leonards, NSW, 2065, Australia
| |
Collapse
|
24
|
Wang S, Colonna M. Microglia in Alzheimer's disease: A target for immunotherapy. J Leukoc Biol 2019; 106:219-227. [PMID: 30725482 DOI: 10.1002/jlb.mr0818-319r] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 01/11/2018] [Accepted: 01/14/2019] [Indexed: 12/29/2022] Open
Abstract
Microglia are resident Mϕs of the CNS that play pleiotropic functions in brain development and homeostasis. Impaired microglial functions are thought to be involved in the onset and progression of various neurodevelopmental and neurodegenerative diseases. Thus, understanding microglia in these settings may indicate new approaches for therapeutic intervention. Here, we review recent evidence implicating microglia in Alzheimer's disease and discuss potential therapeutic strategies targeting microglia and their receptors in this disease.
Collapse
Affiliation(s)
- Shoutang Wang
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri, USA
| |
Collapse
|
25
|
Baskakov IV, Katorcha E, Makarava N. Prion Strain-Specific Structure and Pathology: A View from the Perspective of Glycobiology. Viruses 2018; 10:v10120723. [PMID: 30567302 PMCID: PMC6315442 DOI: 10.3390/v10120723] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 12/13/2018] [Accepted: 12/15/2018] [Indexed: 01/15/2023] Open
Abstract
Prion diseases display multiple disease phenotypes characterized by diverse clinical symptoms, different brain regions affected by the disease, distinct cell tropism and diverse PrPSc deposition patterns. The diversity of disease phenotypes within the same host is attributed to the ability of PrPC to acquire multiple, alternative, conformationally distinct, self-replicating PrPSc states referred to as prion strains or subtypes. Structural diversity of PrPSc strains has been well documented, yet the question of how different PrPSc structures elicit multiple disease phenotypes remains poorly understood. The current article reviews emerging evidence suggesting that carbohydrates in the form of sialylated N-linked glycans, which are a constitutive part of PrPSc, are important players in defining strain-specific structures and disease phenotypes. This article introduces a new hypothesis, according to which individual strain-specific PrPSc structures govern selection of PrPC sialoglycoforms that form strain-specific patterns of carbohydrate epitopes on PrPSc surface and contribute to defining the disease phenotype and outcomes.
Collapse
Affiliation(s)
- Ilia V Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MA 21201, USA.
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MA 21201, USA.
| | - Elizaveta Katorcha
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MA 21201, USA.
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MA 21201, USA.
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MA 21201, USA.
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MA 21201, USA.
| |
Collapse
|
26
|
Inflammatory response of microglia to prions is controlled by sialylation of PrP Sc. Sci Rep 2018; 8:11326. [PMID: 30054538 PMCID: PMC6063910 DOI: 10.1038/s41598-018-29720-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 07/17/2018] [Indexed: 12/22/2022] Open
Abstract
Neuroinflammation is recognized as one of the obligatory pathogenic features of neurodegenerative diseases including Alzheimer’s, Parkinson’s or prion diseases. In prion diseases, space and time correlations between deposition of disease-associated, pathogenic form of the prion protein or PrPSc and microglial-mediated neuroinflammation has been established. Yet, it remains unclear whether activation of microglia is triggered directly by a contact with PrPSc, and what molecular features of PrPSc microglia sense and respond to that drive microglia to inflammatory states. The current study asked the questions whether PrPSc can directly trigger activation of microglia and whether the degree of microglia response depends on the nature of terminal carbohydrate groups on the surface of PrPSc particles. PrPSc was purified from brains of mice infected with mouse-adapted prion strain 22L or neuroblastoma N2a cells stably infected with 22L. BV2 microglial cells or primary microglia were cultured in the presence of purified 22L. We found that exposure of BV2 cells or primary microglia to purified PrPSc triggered proinflammatory responses characterized by an increase in the levels of TNFα, IL6, nitric oxide (NO) and expression of inducible Nitric Oxide Synthase (iNOS). Very similar patterns of inflammatory response were induced by PrPSc purified from mouse brains and neuroblastoma cells arguing that microglia response is independent of the source of PrPSc. To test whether the microglial response is mediated by carbohydrate epitopes on PrPSc surface, the levels of sialylation of PrPSc N-linked glycans was altered by treatment of purified PrPSc with neuraminidase. Partial cleavage of sialic acid residues was found to boost the inflammatory response of microglia to PrPSc. Moreover, transient degradation of Iκβα observed upon treatment with partially desialylated PrPSc suggests that canonical NFκB activation pathway is involved in inflammatory response. The current study is the first to demonstrate that PrPSc can directly trigger inflammatory response in microglia. In addition, this work provides direct evidence that the chemical nature of the carbohydrate groups on PrPSc surface is important for microglial activation.
Collapse
|
27
|
Ledeen RW, Kopitz J, Abad-Rodríguez J, Gabius HJ. Glycan Chains of Gangliosides: Functional Ligands for Tissue Lectins (Siglecs/Galectins). PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 156:289-324. [PMID: 29747818 DOI: 10.1016/bs.pmbts.2017.12.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Molecular signals on the cell surface are responsible for adhesion and communication. Of relevance in this respect, their chemical properties endow carbohydrates with the capacity to store a maximum of information in a minimum of space. One way to present glycans on the cell surface is their covalent conjugation to a ceramide anchor. Among the resulting glycosphingolipids, gangliosides are special due to the presence of at least one sialic acid in the glycan chains. Their spatial accessibility and the dynamic regulation of their profile are factors that argue in favor of a role of glycans of gangliosides as ligands (counterreceptors) for carbohydrate-binding proteins (lectins). Indeed, as discovered first for a bacterial toxin, tissue lectins bind gangliosides and mediate contact formation (trans) and signaling (cis). While siglecs have a preference for higher sialylated glycans, certain galectins also target the monosialylated pentasaccharide of ganglioside GM1. Enzymatic interconversion of ganglioside glycans by sialidase action, relevant for neuroblastoma cell differentiation and growth control in vitro, for axonogenesis and axon regeneration, as well as for proper communication between effector and regulatory T cells, changes lectin-binding affinity profoundly. The GD1a-to-GM1 "editing" is recognized by such lectins, for example, myelin-associated glycoprotein (siglec-4) losing affinity and galectin-1 gaining reactivity, and then translated into postbinding signaling. Orchestrations of loss/gain of affinity, of ganglioside/lectin expression, and of lectin presence in a network offer ample opportunities for fine-tuning. Thus glycans of gangliosides such as GD1a and GM1 are functional counterreceptors by a pairing with tissue lectins, an emerging aspect of ganglioside and lectin functionality.
Collapse
Affiliation(s)
- Robert W Ledeen
- Department of Pharmacology, Physiology & Neuroscience, Rutgers New Jersey Medical School, Newark, NJ, United States.
| | - Jürgen Kopitz
- Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
| | | | | |
Collapse
|
28
|
Biodiversity of CS–proteoglycan sulphation motifs: chemical messenger recognition modules with roles in information transfer, control of cellular behaviour and tissue morphogenesis. Biochem J 2018; 475:587-620. [DOI: 10.1042/bcj20170820] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 12/20/2017] [Accepted: 01/07/2018] [Indexed: 12/19/2022]
Abstract
Chondroitin sulphate (CS) glycosaminoglycan chains on cell and extracellular matrix proteoglycans (PGs) can no longer be regarded as merely hydrodynamic space fillers. Overwhelming evidence over recent years indicates that sulphation motif sequences within the CS chain structure are a source of significant biological information to cells and their surrounding environment. CS sulphation motifs have been shown to interact with a wide variety of bioactive molecules, e.g. cytokines, growth factors, chemokines, morphogenetic proteins, enzymes and enzyme inhibitors, as well as structural components within the extracellular milieu. They are therefore capable of modulating a panoply of signalling pathways, thus controlling diverse cellular behaviours including proliferation, differentiation, migration and matrix synthesis. Consequently, through these motifs, CS PGs play significant roles in the maintenance of tissue homeostasis, morphogenesis, development, growth and disease. Here, we review (i) the biodiversity of CS PGs and their sulphation motif sequences and (ii) the current understanding of the signalling roles they play in regulating cellular behaviour during tissue development, growth, disease and repair.
Collapse
|
29
|
Lannes N, Eppler E, Etemad S, Yotovski P, Filgueira L. Microglia at center stage: a comprehensive review about the versatile and unique residential macrophages of the central nervous system. Oncotarget 2017; 8:114393-114413. [PMID: 29371994 PMCID: PMC5768411 DOI: 10.18632/oncotarget.23106] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 11/15/2017] [Indexed: 02/07/2023] Open
Abstract
Microglia cells are the unique residential macrophages of the central nervous system (CNS). They have a special origin, as they derive from the embryonic yolk sac and enter the developing CNS at a very early stage. They play an important role during CNS development and adult homeostasis. They have a major contribution to adult neurogenesis and neuroinflammation. Thus, they participate in the pathogenesis of neurodegenerative diseases and contribute to aging. They play an important role in sustaining and breaking the blood-brain barrier. As innate immune cells, they contribute substantially to the immune response against infectious agents affecting the CNS. They play also a major role in the growth of tumours of the CNS. Microglia are consequently the key cell population linking the nervous and the immune system. This review covers all different aspects of microglia biology and pathology in a comprehensive way.
Collapse
Affiliation(s)
- Nils Lannes
- Albert Gockel, Anatomy, Department of Medicine, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - Elisabeth Eppler
- Pestalozzistrasse Zo, Department of BioMedicine, University of Basel, CH-4056 Basel, Switzerland
| | - Samar Etemad
- Building 71/218 RBWH Herston, Centre for Clinical Research, The University of Queensland, QLD 4029 Brisbane, Australia
| | - Peter Yotovski
- Albert Gockel, Anatomy, Department of Medicine, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - Luis Filgueira
- Albert Gockel, Anatomy, Department of Medicine, University of Fribourg, CH-1700 Fribourg, Switzerland
| |
Collapse
|
30
|
Katorcha E, Baskakov IV. Analyses of N-linked glycans of PrP Sc revealed predominantly 2,6-linked sialic acid residues. FEBS J 2017; 284:3727-3738. [PMID: 28898525 DOI: 10.1111/febs.14268] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 08/30/2017] [Accepted: 09/08/2017] [Indexed: 12/19/2022]
Abstract
Mammalian prions (PrPSc ) consist of misfolded, conformationally altered, self-replicating states of the sialoglycoprotein called prion protein or PrPC . Recent studies revealed that the sialylation status of PrPSc plays a major role in evading innate immunity and infecting a host. Establishing the type of linkage by which sialic acid residues are attached to galactose is important, as it helps to identify the sialyltransferases responsible for sialylating PrPC and outline strategies for manipulating the sialyation status of PrPSc . Using enzymatic treatment with sialidases and lectin blots, this study demonstrated that in N-linked glycans of PrPSc , the sialic acid residues are predominantly alpha 2,6-linked. High percentages of alpha 2,6-linked sialic acids were observed in PrPSc of three prion strains 22L, RML, and ME7, as well as PrPSc from brain, spleen, or N2a cells cultured in vitro. Moreover, the variation in the percentage of alpha 2,3- versus 2,6-linked sialic acid was found to be relatively minor between brain-, spleen-, or cell-derived PrPSc , suggesting that the type of linkage is independent of tissue type. Based on the current results, we propose that sialyltransferases of St6Gal family, which is responsible for attaching sialic acids via alpha 2,6-linkages to N-linked glycans, controls sialylation of PrPC and PrPSc .
Collapse
Affiliation(s)
- Elizaveta Katorcha
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Ilia V Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, USA.,Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| |
Collapse
|
31
|
Abud EM, Ramirez RN, Martinez ES, Healy LM, Nguyen CHH, Newman SA, Yeromin AV, Scarfone VM, Marsh SE, Fimbres C, Caraway CA, Fote GM, Madany AM, Agrawal A, Kayed R, Gylys KH, Cahalan MD, Cummings BJ, Antel JP, Mortazavi A, Carson MJ, Poon WW, Blurton-Jones M. iPSC-Derived Human Microglia-like Cells to Study Neurological Diseases. Neuron 2017; 94:278-293.e9. [PMID: 28426964 DOI: 10.1016/j.neuron.2017.03.042] [Citation(s) in RCA: 658] [Impact Index Per Article: 94.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 02/16/2017] [Accepted: 03/28/2017] [Indexed: 12/15/2022]
Abstract
Microglia play critical roles in brain development, homeostasis, and neurological disorders. Here, we report that human microglial-like cells (iMGLs) can be differentiated from iPSCs to study their function in neurological diseases, like Alzheimer's disease (AD). We find that iMGLs develop in vitro similarly to microglia in vivo, and whole-transcriptome analysis demonstrates that they are highly similar to cultured adult and fetal human microglia. Functional assessment of iMGLs reveals that they secrete cytokines in response to inflammatory stimuli, migrate and undergo calcium transients, and robustly phagocytose CNS substrates. iMGLs were used to examine the effects of Aβ fibrils and brain-derived tau oligomers on AD-related gene expression and to interrogate mechanisms involved in synaptic pruning. Furthermore, iMGLs transplanted into transgenic mice and human brain organoids resemble microglia in vivo. Together, these findings demonstrate that iMGLs can be used to study microglial function, providing important new insight into human neurological disease.
Collapse
Affiliation(s)
- Edsel M Abud
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Ricardo N Ramirez
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA 92697, USA
| | - Eric S Martinez
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Luke M Healy
- Neuroimmunology Unit, Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, QC H3A 2B4, Canada
| | - Cecilia H H Nguyen
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Sean A Newman
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Andriy V Yeromin
- Department of Physiology and Biophysics, University of California Irvine, Irvine, CA 92697, USA
| | - Vanessa M Scarfone
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA
| | - Samuel E Marsh
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Cristhian Fimbres
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Chad A Caraway
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Gianna M Fote
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA
| | - Abdullah M Madany
- Division of Biomedical Sciences, Center for Glia-Neuronal Interactions, University of California, Riverside, Riverside, CA 92521, USA
| | - Anshu Agrawal
- Department of Medicine, School of Medicine, University of California Irvine, Irvine, CA 92697, USA
| | - Rakez Kayed
- Department of Neurology, George P. and Cynthia Woods Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Karen H Gylys
- UCLA School of Nursing, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Michael D Cahalan
- Department of Physiology and Biophysics, University of California Irvine, Irvine, CA 92697, USA
| | - Brian J Cummings
- Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA; Anatomy and Neurobiology, University of California Irvine, Irvine, CA 92697, USA
| | - Jack P Antel
- Neuroimmunology Unit, Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, Montreal, QC H3A 2B4, Canada
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA 92697, USA
| | - Monica J Carson
- Division of Biomedical Sciences, Center for Glia-Neuronal Interactions, University of California, Riverside, Riverside, CA 92521, USA
| | - Wayne W Poon
- Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA.
| | - Mathew Blurton-Jones
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697, USA; Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697, USA.
| |
Collapse
|
32
|
Colonna M, Butovsky O. Microglia Function in the Central Nervous System During Health and Neurodegeneration. Annu Rev Immunol 2017; 35:441-468. [PMID: 28226226 DOI: 10.1146/annurev-immunol-051116-052358] [Citation(s) in RCA: 1391] [Impact Index Per Article: 198.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Microglia are resident cells of the brain that regulate brain development, maintenance of neuronal networks, and injury repair. Microglia serve as brain macrophages but are distinct from other tissue macrophages owing to their unique homeostatic phenotype and tight regulation by the central nervous system (CNS) microenvironment. They are responsible for the elimination of microbes, dead cells, redundant synapses, protein aggregates, and other particulate and soluble antigens that may endanger the CNS. Furthermore, as the primary source of proinflammatory cytokines, microglia are pivotal mediators of neuroinflammation and can induce or modulate a broad spectrum of cellular responses. Alterations in microglia functionality are implicated in brain development and aging, as well as in neurodegeneration. Recent observations about microglia ontogeny combined with extensive gene expression profiling and novel tools to study microglia biology have allowed us to characterize the spectrum of microglial phenotypes during development, homeostasis, and disease. In this article, we review recent advances in our understanding of the biology of microglia, their contribution to homeostasis, and their involvement in neurodegeneration. Moreover, we highlight the complexity of targeting microglia for therapeutic intervention in neurodegenerative diseases.
Collapse
Affiliation(s)
- Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110;
| | - Oleg Butovsky
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115;
| |
Collapse
|
33
|
Abstract
As the immune-competent cells of the brain, microglia play an increasingly important role in maintaining normal brain function. They invade the brain early in development, transform into a highly ramified phenotype, and constantly screen their environment. Microglia are activated by any type of pathologic event or change in brain homeostasis. This activation process is highly diverse and depends on the context and type of the stressor or pathology. Microglia can strongly influence the pathologic outcome or response to a stressor due to the release of a plethora of substances, including cytokines, chemokines, and growth factors. They are the professional phagocytes of the brain and help orchestrate the immunological response by interacting with infiltrating immune cells. We describe here the diversity of microglia phenotypes and their responses in health, aging, and disease. We also review the current literature about the impact of lifestyle on microglia responses and discuss treatment options that modulate microglial phenotypes.
Collapse
Affiliation(s)
- Susanne A Wolf
- Cellular Neurosciences, Max Delbrück Centre for Molecular Medicine in the Helmholtz Association, Berlin 13092, Germany;
| | - H W G M Boddeke
- Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen 9713, The Netherlands
| | - Helmut Kettenmann
- Cellular Neurosciences, Max Delbrück Centre for Molecular Medicine in the Helmholtz Association, Berlin 13092, Germany;
| |
Collapse
|
34
|
Medeiros LDB, Vitor-de-Lima SM, Lira Benevides RDD, do Egypto Queiroga RDCR, Araújo Guedes RC. Neonatal administration of goat whey modulates memory and cortical spreading depression in rats previously suckled under different litter sizes: Possible role of sialic acid. Nutr Neurosci 2016; 21:108-115. [DOI: 10.1080/1028415x.2016.1227762] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
35
|
Gonzalez-Pena D, Nixon SE, Southey BR, Lawson MA, McCusker RH, Hernandez AG, Dantzer R, Kelley KW, Rodriguez-Zas SL. Differential Transcriptome Networks between IDO1-Knockout and Wild-Type Mice in Brain Microglia and Macrophages. PLoS One 2016; 11:e0157727. [PMID: 27314674 PMCID: PMC4912085 DOI: 10.1371/journal.pone.0157727] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 05/06/2016] [Indexed: 11/19/2022] Open
Abstract
Microglia in the brain and macrophages in peripheral organs are cell types responsible for immune response to challenges. Indoleamine 2,3-dioxygenase 1 (IDO1) is an immunomodulatory enzyme of the tryptophan pathway that is expressed in the brain. The higher activity of IDO1 in response to immune challenge has been implicated in behavioral disorders. The impact of IDO1 depletion on the microglia transcriptome has not been studied. An investigation of the transcript networks in the brain microglia from IDO1-knockout (IDO1-KO) mice was undertaken, relative to peripheral macrophages and to wild-type (WT) mice under unchallenged conditions. Over 105 transcript isoforms were differentially expressed between WT and IDO1-KO within cell type. Within microglia, Saa3 and Irg1 were over-expressed in IDO1-KO relative to WT. Within macrophages, Csf3 and Sele were over-expressed in IDO1-KO relative to WT. Among the genes differentially expressed between strains, enriched biological processes included ion homeostasis and ensheathment of neurons within microglia, and cytokine and chemokine expression within macrophages. Over 11,110 transcript isoforms were differentially expressed between microglia and macrophages and of these, over 10,800 transcripts overlapped between strains. Enriched biological processes among the genes over- and under-expressed in microglia relative to macrophages included cell adhesion and apoptosis, respectively. Detected only in microglia or macrophages were 421 and 43 transcript isoforms, respectively. Alternative splicing between cell types based on differential transcript isoform abundance was detected in 210 genes including Phf11d, H2afy, and Abr. Across strains, networks depicted a predominance of genes under-expressed in microglia relative to macrophages that may be a precursor for the different response of both cell types to challenges. The detected transcriptome differences enhance the understanding of the role of IDO1 in the microglia transcriptome under unchallenged conditions.
Collapse
Affiliation(s)
- Dianelys Gonzalez-Pena
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Scott E. Nixon
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Bruce R. Southey
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Marcus A. Lawson
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Robert H. McCusker
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Alvaro G. Hernandez
- Department of Symptom Research, University of Texas M. D. Anderson Cancer Center, Houston, Texas, United States of America
| | - Robert Dantzer
- High-Throughput Sequencing and Genotyping Unit, Roy J. Carver Biotechnology Center, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Keith W. Kelley
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
| | - Sandra L. Rodriguez-Zas
- Department of Animal Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, United States of America
- Department of Statistics, University of Illinois at Urbana-Champaign, Champaign, Illinois, United States of America
- Carle Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| |
Collapse
|
36
|
Linnartz-Gerlach B, Schuy C, Shahraz A, Tenner AJ, Neumann H. Sialylation of neurites inhibits complement-mediated macrophage removal in a human macrophage-neuron Co-Culture System. Glia 2015; 64:35-47. [PMID: 26257016 DOI: 10.1002/glia.22901] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 07/22/2015] [Accepted: 07/23/2015] [Indexed: 01/08/2023]
Abstract
The complement system has been implicated in the removal of dysfunctional synapses and neurites during development and in disease processes in the mouse, but it is unclear how far the mouse data can be transferred to humans. Here, we co-cultured macrophages derived from human THP1 monocytes and neurons derived from human induced pluripotent stem cells, to study the role of the complement system in a human model. Components of the complement system were expressed by the human macrophages and human neuronal culture, while receptors of the complement cascade were expressed by human macrophages as shown via gene transcript analysis and flow cytometry. We mimicked pathological conditions leading to an altered glycocalyx by treatment of human neurons with sialidases. Desialylated human neurites were opsonized by the complement component C1q. Furthermore, human neurites with an intact sialic acid cap remained untouched, while desialylated human neurites were removed and ingested by human macrophages. While blockage of the complement receptor 1 (CD35) had no effect, blockage of CD11b as part of the complement receptor 3 (CR3) reversed the effect on macrophage phagocytosis of desialylated human neurites. Data demonstrate that in the human system sialylation of the neuronal glycocalyx serves as an inhibitory flag for complement binding and CR3-mediated phagocytosis by macrophages.
Collapse
Affiliation(s)
- Bettina Linnartz-Gerlach
- Neural Regeneration Group, Institute of Reconstructive Neurobiology, University Hospital Bonn, University of Bonn, Bonn, 53127, Germany
| | - Christine Schuy
- Neural Regeneration Group, Institute of Reconstructive Neurobiology, University Hospital Bonn, University of Bonn, Bonn, 53127, Germany
| | - Anahita Shahraz
- Neural Regeneration Group, Institute of Reconstructive Neurobiology, University Hospital Bonn, University of Bonn, Bonn, 53127, Germany
| | - Andrea J Tenner
- Department of Molecular Biology and Biochemistry, Institute for Immunology, University of California, Irvine, California, 92697, USA
| | - Harald Neumann
- Neural Regeneration Group, Institute of Reconstructive Neurobiology, University Hospital Bonn, University of Bonn, Bonn, 53127, Germany
| |
Collapse
|
37
|
Schengrund CL. Gangliosides: glycosphingolipids essential for normal neural development and function. Trends Biochem Sci 2015; 40:397-406. [DOI: 10.1016/j.tibs.2015.03.007] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/17/2015] [Accepted: 03/18/2015] [Indexed: 11/25/2022]
|
38
|
Moreira-Filho CA, Bando SY, Bertonha FB, Iamashita P, Silva FN, Costa LDF, Silva AV, Castro LHM, Wen HT. Community structure analysis of transcriptional networks reveals distinct molecular pathways for early- and late-onset temporal lobe epilepsy with childhood febrile seizures. PLoS One 2015; 10:e0128174. [PMID: 26011637 PMCID: PMC4444281 DOI: 10.1371/journal.pone.0128174] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 04/24/2015] [Indexed: 12/21/2022] Open
Abstract
Age at epilepsy onset has a broad impact on brain plasticity and epilepsy pathomechanisms. Prolonged febrile seizures in early childhood (FS) constitute an initial precipitating insult (IPI) commonly associated with mesial temporal lobe epilepsy (MTLE). FS-MTLE patients may have early disease onset, i.e. just after the IPI, in early childhood, or late-onset, ranging from mid-adolescence to early adult life. The mechanisms governing early (E) or late (L) disease onset are largely unknown. In order to unveil the molecular pathways underlying E and L subtypes of FS-MTLE we investigated global gene expression in hippocampal CA3 explants of FS-MTLE patients submitted to hippocampectomy. Gene coexpression networks (GCNs) were obtained for the E and L patient groups. A network-based approach for GCN analysis was employed allowing: i) the visualization and analysis of differentially expressed (DE) and complete (CO) - all valid GO annotated transcripts - GCNs for the E and L groups; ii) the study of interactions between all the system's constituents based on community detection and coarse-grained community structure methods. We found that the E-DE communities with strongest connection weights harbor highly connected genes mainly related to neural excitability and febrile seizures, whereas in L-DE communities these genes are not only involved in network excitability but also playing roles in other epilepsy-related processes. Inversely, in E-CO the strongly connected communities are related to compensatory pathways (seizure inhibition, neuronal survival and responses to stress conditions) while in L-CO these communities harbor several genes related to pro-epileptic effects, seizure-related mechanisms and vulnerability to epilepsy. These results fit the concept, based on fMRI and behavioral studies, that early onset epilepsies, although impacting more severely the hippocampus, are associated to compensatory mechanisms, while in late MTLE development the brain is less able to generate adaptive mechanisms, what has implications for epilepsy management and drug discovery.
Collapse
Affiliation(s)
| | - Silvia Yumi Bando
- Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil
| | - Fernanda Bernardi Bertonha
- Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil
| | - Priscila Iamashita
- Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil
| | | | | | | | - Luiz Henrique Martins Castro
- Department of Neurology, FMUSP, São Paulo, SP, Brazil
- Clinical Neurology Division, Hospital das Clínicas, FMUSP, São Paulo, SP, Brazil
| | - Hung-Tzu Wen
- Epilepsy Surgery Group, Hospital das Clínicas, FMUSP, São Paulo, SP, Brazil
| |
Collapse
|
39
|
Schmitt S, Castelvetri LC, Simons M. Metabolism and functions of lipids in myelin. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:999-1005. [PMID: 25542507 DOI: 10.1016/j.bbalip.2014.12.016] [Citation(s) in RCA: 164] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/08/2014] [Accepted: 12/16/2014] [Indexed: 12/16/2022]
Abstract
Rapid conduction of nerve impulses requires coating of axons by myelin sheaths, which are lipid-rich and multilamellar membrane stacks. The lipid composition of myelin varies significantly from other biological membranes. Studies in mutant mice targeting various lipid biosynthesis pathways have shown that myelinating glia have a remarkable capacity to compensate the lack of individual lipids. However, compensation fails when it comes to maintaining long-term stability of myelin. Here, we summarize how lipids function in myelin biogenesis, axon-glia communication and in supporting long-term maintenance of myelin. We postulate that change in myelin lipid composition might be relevant for our understanding of aging and demyelinating diseases. This article is part of a Special Issue titled Brain Lipids.
Collapse
Affiliation(s)
- Sebastian Schmitt
- Max-Planck-Institute for Experimental Medicine, Hermann-Rein-Str. 3, Göttingen, Germany; Department of Neurology, Robert-Koch-Str. 40, University of Göttingen, Göttingen, Germany
| | - Ludovici Cantuti Castelvetri
- Max-Planck-Institute for Experimental Medicine, Hermann-Rein-Str. 3, Göttingen, Germany; Department of Neurology, Robert-Koch-Str. 40, University of Göttingen, Göttingen, Germany
| | - Mikael Simons
- Max-Planck-Institute for Experimental Medicine, Hermann-Rein-Str. 3, Göttingen, Germany; Department of Neurology, Robert-Koch-Str. 40, University of Göttingen, Göttingen, Germany.
| |
Collapse
|