1
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Askew KE, Beverley J, Sigfridsson E, Szymkowiak S, Emelianova K, Dando O, Hardingham GE, Duncombe J, Hennessy E, Koudelka J, Samarasekera N, Salman RAS, Smith C, Tavares AAS, Gomez-Nicola D, Kalaria RN, McColl BW, Horsburgh K. Inhibiting CSF1R alleviates cerebrovascular white matter disease and cognitive impairment. Glia 2024; 72:375-395. [PMID: 37909242 PMCID: PMC10952452 DOI: 10.1002/glia.24481] [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: 06/02/2023] [Revised: 09/27/2023] [Accepted: 10/04/2023] [Indexed: 11/02/2023]
Abstract
White matter abnormalities, related to poor cerebral perfusion, are a core feature of small vessel cerebrovascular disease, and critical determinants of vascular cognitive impairment and dementia. Despite this importance there is a lack of treatment options. Proliferation of microglia producing an expanded, reactive population and associated neuroinflammatory alterations have been implicated in the onset and progression of cerebrovascular white matter disease, in patients and in animal models, suggesting that targeting microglial proliferation may exert protection. Colony-stimulating factor-1 receptor (CSF1R) is a key regulator of microglial proliferation. We found that the expression of CSF1R/Csf1r and other markers indicative of increased microglial abundance are significantly elevated in damaged white matter in human cerebrovascular disease and in a clinically relevant mouse model of chronic cerebral hypoperfusion and vascular cognitive impairment. Using the mouse model, we investigated long-term pharmacological CSF1R inhibition, via GW2580, and demonstrated that the expansion of microglial numbers in chronic hypoperfused white matter is prevented. Transcriptomic analysis of hypoperfused white matter tissue showed enrichment of microglial and inflammatory gene sets, including phagocytic genes that were the predominant expression modules modified by CSF1R inhibition. Further, CSF1R inhibition attenuated hypoperfusion-induced white matter pathology and rescued spatial learning impairments and to a lesser extent cognitive flexibility. Overall, this work suggests that inhibition of CSF1R and microglial proliferation mediates protection against chronic cerebrovascular white matter pathology and cognitive deficits. Our study nominates CSF1R as a target for the treatment of vascular cognitive disorders with broader implications for treatment of other chronic white matter diseases.
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Affiliation(s)
- Katharine E Askew
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Joshua Beverley
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Emma Sigfridsson
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Stefan Szymkowiak
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, UK
| | - Katherine Emelianova
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, UK
| | - Owen Dando
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, UK
| | - Giles E Hardingham
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, UK
| | - Jessica Duncombe
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Edel Hennessy
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Juraj Koudelka
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, UK
| | - Neshika Samarasekera
- Centre for Clinical Brain Sciences and Sudden Death Brain Bank, University of Edinburgh, Edinburgh, UK
| | - Rustam Al-Shahi Salman
- Centre for Clinical Brain Sciences and Sudden Death Brain Bank, University of Edinburgh, Edinburgh, UK
| | - Colin Smith
- Centre for Clinical Brain Sciences and Sudden Death Brain Bank, University of Edinburgh, Edinburgh, UK
| | - Adriana A S Tavares
- British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Diego Gomez-Nicola
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Raj N Kalaria
- Clinical and Translational Research Institute, Newcastle University, Newcastle, UK
| | - Barry W McColl
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
- UK Dementia Research Institute, University of Edinburgh, Edinburgh, UK
| | - Karen Horsburgh
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
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2
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Perez JC, Poulen G, Cardoso M, Boukhaddaoui H, Gazard CM, Courtand G, Bertrand SS, Gerber YN, Perrin FE. CSF1R inhibition at chronic stage after spinal cord injury modulates microglia proliferation. Glia 2023; 71:2782-2798. [PMID: 37539655 DOI: 10.1002/glia.24451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 07/03/2023] [Accepted: 07/21/2023] [Indexed: 08/05/2023]
Abstract
Traumatic spinal cord injury (SCI) induces irreversible autonomic and sensory-motor impairments. A large number of patients exhibit chronic SCI and no curative treatment is currently available. Microglia are predominant immune players after SCI, they undergo highly dynamic processes, including proliferation and morphological modification. In a translational aim, we investigated whether microglia proliferation persists at chronic stage after spinal cord hemisection and whether a brief pharmacological treatment could modulate microglial responses. We first carried out a time course analysis of SCI-induced microglia proliferation associated with morphological analysis up to 84 days post-injury (dpi). Second, we analyzed outcomes on microglia of an oral administration of GW2580, a colony stimulating factor-1 receptor tyrosine kinase inhibitor reducing selectively microglia proliferation. After SCI, microglia proliferation remains elevated at 84 dpi. The percentage of proliferative microglia relative to proliferative cells increases over time reaching almost 50% at 84 dpi. Morphological modifications of microglia processes are observed up to 84 dpi and microglia cell body area is transiently increased up to 42 dpi. A transient post-injury GW2580-delivery at two chronic stages after SCI (42 and 84 dpi) reduces microglia proliferation and modifies microglial morphology evoking an overall limitation of secondary inflammation. Finally, transient GW2580-delivery at chronic stage after SCI modulates myelination processes. Together our study shows that there is a persistent microglia proliferation induced by SCI and that a pharmacological treatment at chronic stage after SCI modulates microglial responses. Thus, a transient oral GW2580-delivery at chronic stage after injury may provide a promising therapeutic strategy for chronic SCI patients.
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Affiliation(s)
| | - Gaetan Poulen
- MMDN, Univ. Montpellier, EPHE, INSERM, Montpellier, France
| | - Maida Cardoso
- UMR 5221, Univ. Montpellier, CNRS, Montpellier, France
| | | | | | | | | | | | - Florence Evelyne Perrin
- MMDN, Univ. Montpellier, EPHE, INSERM, Montpellier, France
- Institut Universitaire de France (IUF), Paris, France
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3
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Wang B, Ma Y, Li S, Yao H, Gu M, Liu Y, Xue Y, Ding J, Ma C, Yang S, Hu G. GSDMD in peripheral myeloid cells regulates microglial immune training and neuroinflammation in Parkinson's disease. Acta Pharm Sin B 2023; 13:2663-2679. [PMID: 37425058 PMCID: PMC10326292 DOI: 10.1016/j.apsb.2023.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/16/2023] [Accepted: 03/02/2023] [Indexed: 07/11/2023] Open
Abstract
Peripheral bacterial infections without impaired blood-brain barrier integrity have been attributed to the pathogenesis of Parkinson's disease (PD). Peripheral infection promotes innate immune training in microglia and exacerbates neuroinflammation. However, how changes in the peripheral environment mediate microglial training and exacerbation of infection-related PD is unknown. In this study, we demonstrate that GSDMD activation was enhanced in the spleen but not in the CNS of mice primed with low-dose LPS. GSDMD in peripheral myeloid cells promoted microglial immune training, thus exacerbating neuroinflammation and neurodegeneration during PD in an IL-1R-dependent manner. Furthermore, pharmacological inhibition of GSDMD alleviated the symptoms of PD in experimental PD models. Collectively, these findings demonstrate that GSDMD-induced pyroptosis in myeloid cells initiates neuroinflammation by regulating microglial training during infection-related PD. Based on these findings, GSDMD may serve as a therapeutic target for patients with PD.
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Affiliation(s)
- Bingwei Wang
- School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Yan Ma
- School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Sheng Li
- School of Basic Medical Sciences, Nanjing Medical University, Nanjing 211166, China
| | - Hang Yao
- School of Basic Medical Sciences, Nanjing Medical University, Nanjing 211166, China
| | - Mingna Gu
- School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Ying Liu
- School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - You Xue
- School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Jianhua Ding
- School of Basic Medical Sciences, Nanjing Medical University, Nanjing 211166, China
| | - Chunmei Ma
- School of Basic Medical Sciences, Nanjing Medical University, Nanjing 211166, China
| | - Shuo Yang
- School of Basic Medical Sciences, Nanjing Medical University, Nanjing 211166, China
| | - Gang Hu
- School of Medicine & Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China
- School of Basic Medical Sciences, Nanjing Medical University, Nanjing 211166, China
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4
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Bradford BM, McGuire LI, Hume DA, Pridans C, Mabbott NA. Microglia deficiency accelerates prion disease but does not enhance prion accumulation in the brain. Glia 2022; 70:2169-2187. [PMID: 35852018 PMCID: PMC9544114 DOI: 10.1002/glia.24244] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/24/2022] [Accepted: 06/30/2022] [Indexed: 01/08/2023]
Abstract
Prion diseases are transmissible, neurodegenerative disorders associated with misfolding of the prion protein. Previous studies show that reduction of microglia accelerates central nervous system (CNS) prion disease and increases the accumulation of prions in the brain, suggesting that microglia provide neuroprotection by phagocytosing and destroying prions. In Csf1rΔFIRE mice, the deletion of an enhancer within Csf1r specifically blocks microglia development, however, their brains develop normally and show none of the deficits reported in other microglia-deficient models. Csf1rΔFIRE mice were used as a refined model in which to study the impact of microglia-deficiency on CNS prion disease. Although Csf1rΔFIRE mice succumbed to CNS prion disease much earlier than wild-type mice, the accumulation of prions in their brains was reduced. Instead, astrocytes displayed earlier, non-polarized reactive activation with enhanced phagocytosis of neuronal contents and unfolded protein responses. Our data suggest that rather than simply phagocytosing and destroying prions, the microglia instead provide host-protection during CNS prion disease and restrict the harmful activities of reactive astrocytes.
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Affiliation(s)
- Barry M. Bradford
- The Roslin Institute and R(D)SVSUniversity of Edinburgh, Easter Bush CampusMidlothianUK
| | - Lynne I. McGuire
- The Roslin Institute and R(D)SVSUniversity of Edinburgh, Easter Bush CampusMidlothianUK
| | - David A. Hume
- Mater Research Institute‐University of Queensland, Translational Research InstituteWoolloongabbaQueenslandAustralia
| | - Clare Pridans
- Simons Initiative for the Developing Brain, Centre for Discovery Brain SciencesUniversity of Edinburgh, Hugh Robson BuildingEdinburghUK
- Centre for Inflammation ResearchThe Queen's Medical Research Institute, Edinburgh BioQuarterEdinburghUK
| | - Neil A. Mabbott
- The Roslin Institute and R(D)SVSUniversity of Edinburgh, Easter Bush CampusMidlothianUK
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5
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Xie J, Gorlé N, Vandendriessche C, Van Imschoot G, Van Wonterghem E, Van Cauwenberghe C, Parthoens E, Van Hamme E, Lippens S, Van Hoecke L, Vandenbroucke RE. Low-grade peripheral inflammation affects brain pathology in the App NL-G-Fmouse model of Alzheimer's disease. Acta Neuropathol Commun 2021; 9:163. [PMID: 34620254 PMCID: PMC8499584 DOI: 10.1186/s40478-021-01253-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 09/01/2021] [Indexed: 12/22/2022] Open
Abstract
Alzheimer’s disease (AD) is a chronic neurodegenerative disease characterized by the accumulation of amyloid β (Aβ) and neurofibrillary tangles. The last decade, it became increasingly clear that neuroinflammation plays a key role in both the initiation and progression of AD. Moreover, also the presence of peripheral inflammation has been extensively documented. However, it is still ambiguous whether this observed inflammation is cause or consequence of AD pathogenesis. Recently, this has been studied using amyloid precursor protein (APP) overexpression mouse models of AD. However, the findings might be confounded by APP-overexpression artifacts. Here, we investigated the effect of low-grade peripheral inflammation in the APP knock-in (AppNL-G-F) mouse model. This revealed that low-grade peripheral inflammation affects (1) microglia characteristics, (2) blood-cerebrospinal fluid barrier integrity, (3) peripheral immune cell infiltration and (4) Aβ deposition in the brain. Next, we identified mechanisms that might cause this effect on AD pathology, more precisely Aβ efflux, persistent microglial activation and insufficient Aβ clearance, neuronal dysfunction and promotion of Aβ aggregation. Our results further strengthen the believe that even low-grade peripheral inflammation has detrimental effects on AD progression and may further reinforce the idea to modulate peripheral inflammation as a therapeutic strategy for AD.![]()
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6
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St-Pierre MK, Šimončičová E, Bögi E, Tremblay MÈ. Shedding Light on the Dark Side of the Microglia. ASN Neuro 2021; 12:1759091420925335. [PMID: 32443939 PMCID: PMC7249604 DOI: 10.1177/1759091420925335] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Microglia, the resident immune cells of the central nervous system, are not a
homogeneous population; their morphology, molecular profile, and even their
ultrastructure greatly vary from one cell to another. Recent advances in the
field of neuroimmunology have helped to demystify the enigma that currently
surrounds microglial heterogeneity. Indeed, numerous microglial subtypes have
been discovered such as the disease-associated microglia, neurodegenerative
phenotype, and Cd11c-positive developmental population. Another subtype is the
dark microglia (DM), a population defined by its ultrastructural changes
associated with cellular stress. Since their first characterization using
transmission electron microscopy, they have been identified in numerous disease
conditions, from mouse models of Alzheimer’s disease, schizophrenia, fractalkine
signaling deficiency to chronic stress, just to name a few. A recent study also
identified the presence of cells with a similar ultrastructure to the DM in
postmortem brain samples from schizophrenic patients,
underlining the importance of understanding the function of these cells. In this
minireview, we aim to summarize the current knowledge on the DM, from their
initial ultrastructural characterization to their documentation in various
pathological contexts across multiple species. We will also highlight the
current limitations surrounding the study of these cells and the future that
awaits the DM.
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Affiliation(s)
| | - Eva Šimončičová
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval.,Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin, Slovak Republic.,Institute of Experimental Pharmacology and Toxicology, Centre of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - Eszter Bögi
- Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin, Slovak Republic
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval
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7
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De Sousa VL, Araújo SB, Antonio LM, Silva-Queiroz M, Colodeti LC, Soares C, Barros-Aragão F, Mota-Araujo HP, Alves VS, Coutinho-Silva R, Savio LEB, Ferreira ST, Da Costa R, Clarke JR, Figueiredo CP. Innate immune memory mediates increased susceptibility to Alzheimer's disease-like pathology in sepsis surviving mice. Brain Behav Immun 2021; 95:287-298. [PMID: 33838250 DOI: 10.1016/j.bbi.2021.04.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 03/12/2021] [Accepted: 04/03/2021] [Indexed: 12/14/2022] Open
Abstract
Sepsis survivors show long-term impairments, including alterations in memory and executive function. Evidence suggests that systemic inflammation contributes to the progression of Alzheimeŕs disease (AD), but the mechanisms involved in this process are still unclear. Boosted (trained) and diminished (tolerant) innate immune memory has been described in peripheral immune cells after sepsis. However, the occurrence of long-term innate immune memory in the post-septic brain is fully unexplored. Here, we demonstrate that sepsis causes long-lasting trained innate immune memory in the mouse brain, leading to an increased susceptibility to Aβ oligomers (AβO), central neurotoxins found in AD. Hippocampal microglia from sepsis-surviving mice shift to an amoeboid/phagocytic morphological profile when exposed to low amounts of AβO, and this event was accompanied by the upregulation of several pro-inflammatory proteins (IL-1β, IL-6, INF-γ and P2X7 receptor) in the mouse hippocampus, suggesting that a trained innate immune memory occurs in the brain after sepsis. Brain exposure to low amounts of AβO increased microglial phagocytic ability against hippocampal synapses. Pharmacological blockage of brain phagocytic cells or microglial depletion, using minocycline and colony stimulating factor 1 receptor inhibitor (PLX3397), respectively, prevents cognitive dysfunction induced by AβO in sepsis-surviving mice. Altogether, our findings suggest that sepsis induces a long-lasting trained innate immune memory in the mouse brain, leading to an increased susceptibility to AβO-induced neurotoxicity and cognitive impairment.
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Affiliation(s)
- Virginia L De Sousa
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Suzana B Araújo
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Leticia M Antonio
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Mariana Silva-Queiroz
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Lilian C Colodeti
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Carolina Soares
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Fernanda Barros-Aragão
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil; Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Hannah P Mota-Araujo
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Vinícius S Alves
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Robson Coutinho-Silva
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Luiz Eduardo B Savio
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Sergio T Ferreira
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil; Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil; Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Robson Da Costa
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil
| | - Julia R Clarke
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil; Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil.
| | - Claudia P Figueiredo
- School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil; Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21944-590, Brazil.
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8
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Scott MC, Bedi SS, Olson SD, Sears CM, Cox CS. Microglia as therapeutic targets after neurological injury: strategy for cell therapy. Expert Opin Ther Targets 2021; 25:365-380. [PMID: 34029505 DOI: 10.1080/14728222.2021.1934447] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Microglia is the resident tissue macrophages of the central nervous system. Prolonged microglial activation often occurs after traumatic brain injury and is associated with deteriorating neurocognitive outcomes. Resolution of microglial activation is associated with limited tissue loss and improved neurocognitive outcomes. Limiting the prolonged pro-inflammatory response and the associated secondary tissue injury provides the rationale and scientific premise for considering microglia as a therapeutic target. AREAS COVERED In this review, we discuss markers of microglial activation, such as immunophenotype and microglial response to injury, including cytokine/chemokine release, free radical formation, morphology, phagocytosis, and metabolic shifts. We compare the origin and role in neuroinflammation of microglia and monocytes/macrophages. We review potential therapeutic targets to shift microglial polarization. Finally, we review the effect of cell therapy on microglia. EXPERT OPINION Dysregulated microglial activation after neurologic injury, such as traumatic brain injury, can worsen tissue damage and functional outcomes. There are potential targets in microglia to attenuate this activation, such as proteins and molecules that regulate microglia polarization. Cellular therapeutics that limit, but do not eliminate, the inflammatory response have improved outcomes in animal models by reducing pro-inflammatory microglial activation via secondary signaling. These findings have been replicated in early phase clinical trials.
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Affiliation(s)
- M Collins Scott
- Department of Pediatric Surgery, University of Texas Health Science Center at Houston (Uthealth), USA
| | - Supinder S Bedi
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
| | - Scott D Olson
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
| | - Candice M Sears
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
| | - Charles S Cox
- Department of Pediatric Surgery, University of Texas Medical School at Houston, Houston, Texas, USA
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9
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Neuroinflammation in Prion Disease. Int J Mol Sci 2021; 22:ijms22042196. [PMID: 33672129 PMCID: PMC7926464 DOI: 10.3390/ijms22042196] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 02/20/2021] [Accepted: 02/20/2021] [Indexed: 12/24/2022] Open
Abstract
Neuroinflammation, typically manifest as microglial activation and astrogliosis accompanied by transcriptomic alterations, represents a common hallmark of various neurodegenerative conditions including prion diseases. Microglia play an overall neuroprotective role in prion disease, whereas reactive astrocytes with aberrant phenotypes propagate prions and contribute to prion-induced neurodegeneration. The existence of heterogeneous subpopulations and dual functions of microglia and astrocytes in prion disease make them potential targets for therapeutic intervention. A variety of neuroinflammation-related molecules are involved in prion pathogenesis. Therapeutics targeting neuroinflammation represents a novel approach to combat prion disease. Deciphering neuroinflammation in prion disease will deepen our understanding of pathogenesis of other neurodegenerative disorders.
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10
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Mabbott NA, Bradford BM, Pal R, Young R, Donaldson DS. The Effects of Immune System Modulation on Prion Disease Susceptibility and Pathogenesis. Int J Mol Sci 2020; 21:E7299. [PMID: 33023255 PMCID: PMC7582561 DOI: 10.3390/ijms21197299] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 09/25/2020] [Accepted: 09/29/2020] [Indexed: 12/17/2022] Open
Abstract
Prion diseases are a unique group of infectious chronic neurodegenerative disorders to which there are no cures. Although prion infections do not stimulate adaptive immune responses in infected individuals, the actions of certain immune cell populations can have a significant impact on disease pathogenesis. After infection, the targeting of peripherally-acquired prions to specific immune cells in the secondary lymphoid organs (SLO), such as the lymph nodes and spleen, is essential for the efficient transmission of disease to the brain. Once the prions reach the brain, interactions with other immune cell populations can provide either host protection or accelerate the neurodegeneration. In this review, we provide a detailed account of how factors such as inflammation, ageing and pathogen co-infection can affect prion disease pathogenesis and susceptibility. For example, we discuss how changes to the abundance, function and activation status of specific immune cell populations can affect the transmission of prion diseases by peripheral routes. We also describe how the effects of systemic inflammation on certain glial cell subsets in the brains of infected individuals can accelerate the neurodegeneration. A detailed understanding of the factors that affect prion disease transmission and pathogenesis is essential for the development of novel intervention strategies.
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Affiliation(s)
- Neil A. Mabbott
- The Roslin Institute & Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK; (B.M.B.); (R.P.); (R.Y.); (D.S.D.)
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11
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Park D, Kim S, Kim H, Shin J, Jung H, Um JW. Seizure progression triggered by
IQSEC3
loss is mitigated by reducing activated microglia in mice. Glia 2020; 68:2661-2673. [DOI: 10.1002/glia.23876] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/29/2020] [Accepted: 06/04/2020] [Indexed: 01/02/2023]
Affiliation(s)
- Dongseok Park
- Department of Brain and Cognitive Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu South Korea
| | - Seungjoon Kim
- Department of Brain and Cognitive Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu South Korea
| | - Hyeonho Kim
- Department of Brain and Cognitive Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu South Korea
| | - Jungsu Shin
- Department of Brain and Cognitive Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu South Korea
| | - Hyeji Jung
- Department of Brain and Cognitive Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu South Korea
| | - Ji Won Um
- Department of Brain and Cognitive Sciences Daegu Gyeongbuk Institute of Science and Technology (DGIST) Daegu South Korea
- Core Protein Resources Center, DGIST Daegu South Korea
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12
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McPherson SW, Heuss ND, Lehmann U, Roehrich H, Abedin M, Gregerson DS. The retinal environment induces microglia-like properties in recruited myeloid cells. J Neuroinflammation 2019; 16:151. [PMID: 31325968 PMCID: PMC6642741 DOI: 10.1186/s12974-019-1546-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/11/2019] [Indexed: 12/31/2022] Open
Abstract
Background Microglia are essential to the development of the CNS and its homeostasis. Our prior findings suggested a niche model to describe the behaviors of retinal microglia. Here, we ask whether new myeloid cells recruited to the retina are constrained to resemble endogenous microglia morphologically and functionally. Methods Use of CD11cDTR/GFP transgenic mouse allowed identification of two niches of retinal microglia distinguished by being GFPlo or GFPhi. We also used transgenic mice in which CX3CR1+ cells expressed YFP and were depletable following tamoxifen-induced expression of diphtheria toxin subunit A. We employed several ablation and injury stimulation protocols to examine the origin and fate of myeloid cells repopulating the retina. Analysis of retinal myeloid cells was done by microscopy, flow cytometry, and qRT-PCR. Results We found that the origin of new GFPhi and GFPlo myeloid cells in the retina of CD11cDTR/GFP mice, whether recruited or local, depended on the ablation and stimulation protocols. Regardless of origin, new GFPlo and GFPhi retinal myeloid cells were CD45medCD11b+Ly6G−Ly6CloIba1+F4/80+, similar to endogenous microglia. Following tamoxifen-induced diphtheria toxin ablation, myeloid cell repopulation differed in the retina compared to the brain and optic nerve. Stimulation of replacement GFPhi cells was substantially attenuated in repopulating retinas after tamoxifen-induced diphtheria toxin ablation compared to control or radiation-ablated mice. In radiation bone marrow chimeric mice, replacement GFPhi myeloid cells from the circulation were slow to repopulate the retina unless stimulated by an optic nerve crush injury. However, once stimulated, recruited GFPhi cells were found to concentrate on injured retinal ganglion cells and were morphologically similar to GFPhi cells in non-ablated control CD11cDTR/GFP mice. Conclusions The results support the idea that GFPhi cells in the CD11cDTR/GFP mouse, whether recruited or from resident microglia, mark a unique niche of activated retinal myeloid cells. We conclude that the retinal environment has a potent influence on the function, morphology, and proliferative capacity of new myeloid cells regardless of their origin, compelling them to be equivalent to the endogenous microglia. Electronic supplementary material The online version of this article (10.1186/s12974-019-1546-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Scott W McPherson
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, 2001 6th Street SE, LRB Room 314, Minneapolis, MN, 55455, USA.
| | - Neal D Heuss
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, 2001 6th Street SE, LRB Room 314, Minneapolis, MN, 55455, USA
| | - Ute Lehmann
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, 2001 6th Street SE, LRB Room 314, Minneapolis, MN, 55455, USA
| | - Heidi Roehrich
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, 2001 6th Street SE, LRB Room 314, Minneapolis, MN, 55455, USA
| | - Md Abedin
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, 2001 6th Street SE, LRB Room 314, Minneapolis, MN, 55455, USA
| | - Dale S Gregerson
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, 2001 6th Street SE, LRB Room 314, Minneapolis, MN, 55455, USA
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13
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Neher JJ, Cunningham C. Priming Microglia for Innate Immune Memory in the Brain. Trends Immunol 2019; 40:358-374. [DOI: 10.1016/j.it.2019.02.001] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 01/30/2019] [Accepted: 02/01/2019] [Indexed: 01/16/2023]
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14
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Keller A, Nuvolone M, Abakumova I, Chincisan A, Reimann R, Avar M, Heinzer D, Hornemann S, Wagner J, Kirschenbaum D, Voigt FF, Zhu C, Regli L, Helmchen F, Aguzzi A. Prion pathogenesis is unaltered in a mouse strain with a permeable blood-brain barrier. PLoS Pathog 2018; 14:e1007424. [PMID: 30496289 PMCID: PMC6264140 DOI: 10.1371/journal.ppat.1007424] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 10/19/2018] [Indexed: 01/01/2023] Open
Abstract
Transmissible spongiform encephalopathies (TSEs) are caused by the prion, which consists essentially of PrPSc, an aggregated, conformationally modified form of the cellular prion protein (PrPC). Although TSEs can be experimentally transmitted by intracerebral inoculation, most instances of infection in the field occur through extracerebral routes. The epidemics of kuru and variant Creutzfeldt-Jakob disease were caused by dietary exposure to prions, and parenteral administration of prion-contaminated hormones has caused hundreds of iatrogenic TSEs. In all these instances, the development of postexposure prophylaxis relies on understanding of how prions propagate from the site of entry to the brain. While much evidence points to lymphoreticular invasion followed by retrograde transfer through peripheral nerves, prions are present in the blood and may conceivably cross the blood-brain barrier directly. Here we have addressed the role of the blood-brain barrier (BBB) in prion disease propagation using Pdgfbret/ret mice which possess a highly permeable BBB. We found that Pdgfbret/ret mice have a similar prion disease incubation time as their littermate controls regardless of the route of prion transmission. These surprising results indicate that BBB permeability is irrelevant to the initiation of prion disease, even when prions are administered parenterally.
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Affiliation(s)
- Annika Keller
- Department of Neurosurgery, Clinical Neuroscience Centre, University Hospital Zürich, Zürich University, Zürich, Switzerland
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Mario Nuvolone
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
- Amyloidosis Research and Treatment Center, Foundation IRCCS Policlinico San Matteo, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Irina Abakumova
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Andra Chincisan
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Regina Reimann
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Merve Avar
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Daniel Heinzer
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Simone Hornemann
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Josephin Wagner
- Department of Neurosurgery, Clinical Neuroscience Centre, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Daniel Kirschenbaum
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Fabian F. Voigt
- Brain Research Institute, Zürich University, Zürich, Switzerland
- Neuroscience Center Zürich (ZNZ), University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Caihong Zhu
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Luca Regli
- Department of Neurosurgery, Clinical Neuroscience Centre, University Hospital Zürich, Zürich University, Zürich, Switzerland
| | - Fritjof Helmchen
- Brain Research Institute, Zürich University, Zürich, Switzerland
- Neuroscience Center Zürich (ZNZ), University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital Zürich, Zürich University, Zürich, Switzerland
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Krbot K, Hermann P, Skorić MK, Zerr I, Sepulveda-Falla D, Goebel S, Matschke J, Krasemann S, Glatzel M. Distinct microglia profile in Creutzfeldt-Jakob disease and Alzheimer's disease is independent of disease kinetics. Neuropathology 2018; 38:591-600. [PMID: 30318820 DOI: 10.1111/neup.12517] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 08/16/2018] [Accepted: 08/25/2018] [Indexed: 12/15/2022]
Abstract
Activated microglia represent a common pathological feature of neurodegenerative diseases. Sporadic Creutzfeldt-Jakob disease (sCJD) patients show more pronounced microglial activation than Alzheimer's disease (AD) patients. Whether these differences are due to differences in disease kinetics or represent disease-specific changes is unknown. We investigated microglial phenotypes in brains of rapidly progressive AD (rpAD) and sCJD patients matched for clinical presentation, including disease duration. We immunostained the frontal cortex, basal ganglia and cerebellum in 16 patients with rpAD and sCJD using antibodies against markers of microglia and recruited monocytes (ionized calcium-binding adaptor molecule 1, human leukocyte antigen DPQR, Cluster of Differentiation 68), an antibody unique to brain-resident microglia (transmembrane protein 119 (TMEM119)), in addition to antibodies against a marker of astrocytes (glial fibrillary acidic protein), amyloid-β (Aβ) and pathological prion protein. rpAD patients showed a distinct microglial phenotype with a high abundance of TMEM119-positive microglia in all investigated regions. Presence of Aβ deposits seen in a sCJD patient with concomitant deposition of Aβ led to increase of TMEM119-positive microglia. Our data suggest that in rpAD, activation of brain-resident microglia significantly contributes to microgliosis, whereas in sCJD the TMEM119 signature of resident microglial cells is barely detectable. This is irrespective of disease duration and may indicate disease-specific microglial reaction.
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Affiliation(s)
- Katarina Krbot
- Institute of Neuropathology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Peter Hermann
- National TSE Reference Centre, Department of Neurology, Georg-August University Goettingen, Germany
| | | | - Inga Zerr
- National TSE Reference Centre, Department of Neurology, Georg-August University Goettingen, Germany
| | - Diego Sepulveda-Falla
- Institute of Neuropathology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan Goebel
- National TSE Reference Centre, Department of Neurology, Georg-August University Goettingen, Germany
| | - Jakob Matschke
- Institute of Neuropathology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Susanne Krasemann
- Institute of Neuropathology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Markus Glatzel
- Institute of Neuropathology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
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Zhang L, Ma P, Guan Q, Meng L, Su L, Wang L, Yuan B. Effect of chemokine CC ligand 2 (CCL2) on α‑synuclein‑induced microglia proliferation and neuronal apoptosis. Mol Med Rep 2018; 18:4213-4218. [PMID: 30221727 PMCID: PMC6172395 DOI: 10.3892/mmr.2018.9468] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Accepted: 06/29/2018] [Indexed: 12/22/2022] Open
Abstract
The present study aimed to investigate the effect of chemokine CC ligand 2 (CCL2) on α‑synuclein‑mediated microglia proliferation and neuronal apoptosis. Primary cultured microglia and primary neurons were isolated and cultured in vitro. Microglia were divided into four groups: The cells in the control group were treated with an identical amount of PBS, whereas the cells in the CCL2 group were cultured in medium containing 0.05 ng/µl CCL2; cells in the α‑synuclein group were treated with medium containing 0.2 ng/µl α‑synuclein; and cells in the CCL2 plus α‑synuclein group were cultured in medium containing 0.05 ng/µl CCL2 and 0.2 ng/µl α‑synuclein. After incubation for 24 h, the proliferation of glial cells, and the level of α‑synuclein in the cells, were measured. The levels of tumor necrosis factor‑α (TNF‑α), interleukin‑1β (IL‑1β) and nitric oxide (NO) in the culture medium were also measured. Levels of cleaved caspase‑3, Akt and phosphorylated (p)‑Akt in neurons treated with primary microglia culture medium in each group were subsequently monitored. The proliferation activity and secretion of TNF‑α, IL‑1β and NO in the CCL2, α‑synuclein and CCL2 plus α‑synuclein groups were significantly higher compared with that in the control group (P<0.05), as were the levels of α‑synuclein (P<0.01). The levels of neuronal apoptosis and cleaved caspase‑3 protein in the CCL2, α‑synuclein and CCL2 plus α‑synuclein groups were also significantly higher compared with that in the control group (P<0.01). Taken together, these results have demonstrated that CCL2 is able to promote α‑synuclein secretion and the apoptosis of neurons induced by α‑synuclein, thus inducing proliferation of the microglia and secretion of TNF‑α, IL‑1β and NO.
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Affiliation(s)
- Lijun Zhang
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China
| | - Pengju Ma
- Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China
| | - Qingkai Guan
- Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China
| | - Lei Meng
- Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China
| | - Linlin Su
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China
| | - Lina Wang
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China
| | - Bin Yuan
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453000, P.R. China
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Rakic S, Hung YMA, Smith M, So D, Tayler HM, Varney W, Wild J, Harris S, Holmes C, Love S, Stewart W, Nicoll JAR, Boche D. Systemic infection modifies the neuroinflammatory response in late stage Alzheimer's disease. Acta Neuropathol Commun 2018; 6:88. [PMID: 30193587 PMCID: PMC6127939 DOI: 10.1186/s40478-018-0592-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 08/30/2018] [Indexed: 02/04/2023] Open
Abstract
Clinical studies indicate that systemic infections accelerate cognitive decline in Alzheimer’s disease. Animal models suggest that this may be due to enhanced pro-inflammatory changes in the brain. We have performed a post-mortem human study to determine whether systemic infection modifies the neuropathology and in particular, neuroinflammation, in the late-stage of the disease. Sections of cerebral cortex and underlying white matter from controls and Alzheimer's patients who died with or without a terminal systemic infection were immunolabelled and quantified for: (i) Αβ and phosphorylated-tau; (ii) the inflammation-related proteins Iba1, CD68, HLA-DR, FcγRs (CD64, CD32a, CD32b, CD16), CHIL3L1, IL4R and CCR2; and (iii) T-cell marker CD3. In Alzheimer's disease, the synaptic proteins synaptophysin and PSD-95 were quantified by ELISA, and the inflammatory proteins and mRNAs by MesoScale Discovery Multiplex Assays and qPCR, respectively. Systemic infection in Alzheimer's disease was associated with decreased CD16 (p = 0.027, grey matter) and CD68 (p = 0.015, white matter); increased CD64 (p = 0.017, white matter) as well as increased protein expression of IL6 (p = 0.047) and decreased IL5 (p = 0.007), IL7 (p = 0.002), IL12/IL23p40 (p = 0.001), IL15 (p = 0.008), IL16 (p < 0.001) and IL17A (p < 0.001). Increased expression of anti-inflammatory genes CHI3L1 (p = 0.012) and IL4R (p = 0.004) were detected in this group. T-cell recruitment to the brain was reduced when systemic infection was present. However, exposure to systemic infection did not modify the pathology. In Alzheimer's disease, CD68 (p = 0.026), CD64 (p = 0.002), CHI3L1 (p = 0.016), IL4R (p = 0.005) and CCR2 (p = 0.010) were increased independently of systemic infection. Our findings suggest that systemic infections modify neuroinflammatory processes in Alzheimer's disease. However, rather than promoting pro-inflammatory changes, as observed in experimental models, they seem to promote an anti-inflammatory, potentially immunosuppressive, environment in the human brain.
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18
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A story of birth and death: Insights into the formation and dynamics of the microglial population. Brain Behav Immun 2018; 69:9-17. [PMID: 28341583 DOI: 10.1016/j.bbi.2017.03.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/16/2017] [Accepted: 03/20/2017] [Indexed: 12/24/2022] Open
Abstract
Microglia are the main resident immunocompetent cells of the brain with key roles in brain development, homeostasis and function. Here we briefly review our current knowledge of the homeostatic mechanisms regulating the composition and turnover of the microglial population under physiological conditions from development to ageing. A greater understanding of these mechanisms may inform understanding of how dysregulation of microglial dynamics could contribute to the pathogenesis and/or progression of neurological disorders.
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20
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Mabbott NA. How do PrP Sc Prions Spread between Host Species, and within Hosts? Pathogens 2017; 6:pathogens6040060. [PMID: 29186791 PMCID: PMC5750584 DOI: 10.3390/pathogens6040060] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 11/16/2017] [Accepted: 11/21/2017] [Indexed: 12/22/2022] Open
Abstract
Prion diseases are sub-acute neurodegenerative diseases that affect humans and some domestic and free-ranging animals. Infectious prion agents are considered to comprise solely of abnormally folded isoforms of the cellular prion protein known as PrPSc. Pathology during prion disease is restricted to the central nervous system where it causes extensive neurodegeneration and ultimately leads to the death of the host. The first half of this review provides a thorough account of our understanding of the various ways in which PrPSc prions may spread between individuals within a population, both horizontally and vertically. Many natural prion diseases are acquired peripherally, such as by oral exposure, lesions to skin or mucous membranes, and possibly also via the nasal cavity. Following peripheral exposure, some prions accumulate to high levels within the secondary lymphoid organs as they make their journey from the site of infection to the brain, a process termed neuroinvasion. The replication of PrPSc prions within secondary lymphoid organs is important for their efficient spread to the brain. The second half of this review describes the key tissues, cells and molecules which are involved in the propagation of PrPSc prions from peripheral sites of exposure (such as the lumen of the intestine) to the brain. This section also considers how additional factors such as inflammation and aging might influence prion disease susceptibility.
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Affiliation(s)
- Neil A Mabbott
- The Roslin Institute & Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
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21
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Mabbott NA. Immunology of Prion Protein and Prions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2017; 150:203-240. [PMID: 28838662 DOI: 10.1016/bs.pmbts.2017.06.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Many natural prion diseases are acquired peripherally, such as following the oral consumption of contaminated food or pasture. After peripheral exposure many prion isolates initially accumulate to high levels within the host's secondary lymphoid tissues. The replication of prions within these tissues is essential for their efficient spread to the brain where they ultimately cause neurodegeneration. This chapter describes our current understanding of the critical tissues, cells, and molecules which the prions exploit to mediate their efficient propagation from the site of exposure (such as the intestine) to the brain. Interactions between the immune system and prions are not only restricted to the secondary lymphoid tissues. Therefore, an account of how the activation status of the microglial in the brain can also influence progression of prion disease pathogenesis is provided. Prion disease susceptibility may also be influenced by additional factors such as chronic inflammation, coinfection with other pathogens, and aging. Finally, the potential for immunotherapy to provide a means of safe and effective prophylactic or therapeutic intervention in these currently untreatable diseases is considered.
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Affiliation(s)
- Neil A Mabbott
- The Roslin Institute & Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Midlothian, United Kingdom.
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22
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Lund H, Pieber M, Harris RA. Lessons Learned about Neurodegeneration from Microglia and Monocyte Depletion Studies. Front Aging Neurosci 2017; 9:234. [PMID: 28804456 PMCID: PMC5532389 DOI: 10.3389/fnagi.2017.00234] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 07/05/2017] [Indexed: 12/20/2022] Open
Abstract
While bone marrow-derived Ly6Chi monocytes can infiltrate the central nervous system (CNS) they are developmentally and functionally distinct from resident microglia. Our understanding of the relative importance of these two populations in the distinct processes of pathogenesis and resolution of inflammation during neurodegenerative disorders was limited by a lack of tools to specifically manipulate each cell type. During recent years, the development of experimental cell-specific depletion models has enabled this issue to be addressed. Herein we compare and contrast the different depletion approaches that have been used, focusing on the respective functionalities of microglia and monocyte-derived macrophages in a range of neurodegenerative disease states, and discuss their prospects for immunotherapy.
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Affiliation(s)
- Harald Lund
- Department of Clinical Neuroscience, Karolinska Institutet, Centre for Molecular Medicine, Karolinska Hospital at SolnaSolna, Sweden
| | - Melanie Pieber
- Department of Clinical Neuroscience, Karolinska Institutet, Centre for Molecular Medicine, Karolinska Hospital at SolnaSolna, Sweden
| | - Robert A Harris
- Department of Clinical Neuroscience, Karolinska Institutet, Centre for Molecular Medicine, Karolinska Hospital at SolnaSolna, Sweden
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Abstract
Prion diseases are a group of progressive and fatal neurodegenerative disorders characterized by deposition of scrapie prion protein (PrPSc) in the CNS. This deposition is accompanied by neuronal loss, spongiform change, astrogliosis, and conspicuous microglial activation. Here, we argue that microglia play an overall neuroprotective role in prion pathogenesis. Several microglia-related molecules, such as Toll-like receptors (TLRs), the complement system, cytokines, chemokines, inflammatory regulators, and phagocytosis mediators, are involved in prion pathogenesis. However, the molecular mechanisms underlying the microglial response to prion infection are largely unknown. Consequently, we lack a comprehensive understanding of the regulatory network of microglial activation. On the positive side, recent findings suggest that therapeutic strategies modulating microglial activation and function may have merit in prion disease. Moreover, studies on the role of microglia in prion disease could deepen our understanding of neuroinflammation in a broad range of neurodegenerative disorders.
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Obst J, Simon E, Mancuso R, Gomez-Nicola D. The Role of Microglia in Prion Diseases: A Paradigm of Functional Diversity. Front Aging Neurosci 2017; 9:207. [PMID: 28690540 PMCID: PMC5481309 DOI: 10.3389/fnagi.2017.00207] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 06/09/2017] [Indexed: 12/26/2022] Open
Abstract
Inflammation is a major component of neurodegenerative diseases. Microglia are the innate immune cells in the central nervous system (CNS). In the healthy brain, microglia contribute to tissue homeostasis and regulation of synaptic plasticity. Under disease conditions, they play a key role in the development and maintenance of the neuroinflammatory response, by showing enhanced proliferation and activation. Prion diseases are progressive chronic neurodegenerative disorders associated with the accumulation of the scrapie prion protein PrPSc, a misfolded conformer of the cellular prion protein PrPC. This review article provides the current knowledge on the role of microglia in the pathogenesis of prion disease. A large body of evidence shows that microglia can trigger neurotoxic pathways contributing to progressive degeneration. Yet, microglia are also crucial for controlling inflammatory, repair and regenerative processes. This dual role of microglia is regulated by multiple pathways and evidences the ability of these cells to polarize into distinct phenotypes with characteristic functions. The awareness that the neuroinflammatory response is inextricably involved in producing tissue damage as well as repair in neurodegenerative disorders, opens new perspectives for the modulation of the immune system. A better understanding of this complex process will be essential for developing effective therapies for neurodegenerative diseases, in order to improve the quality of life of patients and mitigating the personal, economic and social consequences derived from these diseases.
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Affiliation(s)
- Juliane Obst
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
| | - Emilie Simon
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
| | - Renzo Mancuso
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
| | - Diego Gomez-Nicola
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
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Coles JA, Myburgh E, Brewer JM, McMenamin PG. Where are we? The anatomy of the murine cortical meninges revisited for intravital imaging, immunology, and clearance of waste from the brain. Prog Neurobiol 2017; 156:107-148. [PMID: 28552391 DOI: 10.1016/j.pneurobio.2017.05.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 04/25/2017] [Accepted: 05/08/2017] [Indexed: 12/15/2022]
Abstract
Rapid progress is being made in understanding the roles of the cerebral meninges in the maintenance of normal brain function, in immune surveillance, and as a site of disease. Most basic research on the meninges and the neural brain is now done on mice, major attractions being the availability of reporter mice with fluorescent cells, and of a huge range of antibodies useful for immunocytochemistry and the characterization of isolated cells. In addition, two-photon microscopy through the unperforated calvaria allows intravital imaging of the undisturbed meninges with sub-micron resolution. The anatomy of the dorsal meninges of the mouse (and, indeed, of all mammals) differs considerably from that shown in many published diagrams: over cortical convexities, the outer layer, the dura, is usually thicker than the inner layer, the leptomeninx, and both layers are richly vascularized and innervated, and communicate with the lymphatic system. A membrane barrier separates them and, in disease, inflammation can be localized to one layer or the other, so experimentalists must be able to identify the compartment they are studying. Here, we present current knowledge of the functional anatomy of the meninges, particularly as it appears in intravital imaging, and review their role as a gateway between the brain, blood, and lymphatics, drawing on information that is scattered among works on different pathologies.
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Affiliation(s)
- Jonathan A Coles
- Centre for Immunobiology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davis Building, University of Glasgow, Glasgow, G12 8TA, United Kingdom.
| | - Elmarie Myburgh
- Centre for Immunology and Infection Department of Biology, University of York, Wentworth Way, Heslington, York YO10 5DD, United Kingdom
| | - James M Brewer
- Centre for Immunobiology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davis Building, University of Glasgow, Glasgow, G12 8TA, United Kingdom
| | - Paul G McMenamin
- Department of Anatomy & Developmental Biology, School of Biomedical and Psychological Sciences and Monash Biomedical Discovery Institute, Faculty of Medicine, Nursing and Health Sciences, Monash University, 10 Chancellor's Walk, Clayton, Victoria, 3800, Australia
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Weber MD, Godbout JP, Sheridan JF. Repeated Social Defeat, Neuroinflammation, and Behavior: Monocytes Carry the Signal. Neuropsychopharmacology 2017; 42:46-61. [PMID: 27319971 PMCID: PMC5143478 DOI: 10.1038/npp.2016.102] [Citation(s) in RCA: 183] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/28/2016] [Accepted: 05/27/2016] [Indexed: 02/06/2023]
Abstract
Mounting evidence indicates that proinflammatory signaling in the brain affects mood, cognition, and behavior and is linked with the etiology of psychiatric disorders, including anxiety and depression. The purpose of this review is to focus on stress-induced bidirectional communication pathways between the central nervous system (CNS) and peripheral immune system that converge to promote a heightened neuroinflammatory environment. These communication pathways involve sympathetic outflow from the brain to the peripheral immune system that biases hematopoietic stem cells to differentiate into a glucocorticoid-resistant and primed myeloid lineage immune cell. In conjunction, microglia-dependent neuroinflammatory events promote myeloid cell trafficking to the brain that reinforces stress-related behavior, and is argued to play a role in stress-related psychiatric disorders. We will discuss evidence implicating a key role for endothelial cells that comprise the blood-brain barrier in propagating peripheral-to-central immune communication. We will also discuss novel neuron-to-glia communication pathways involving endogenous danger signals that have recently been argued to facilitate neuroinflammation under various conditions, including stress. These findings help elucidate the complex communication that occurs in response to stress and highlight novel therapeutic targets against the development of stress-related psychiatric disorders.
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Affiliation(s)
- Michael D Weber
- Division of Biosciences, The Ohio State University, Columbus, OH, USA,Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA,Division of Biosciences, The Ohio State University, 223 IBMR Building, 305 W 12th Avenue, 460 Medical Center Drive, Columbus, OH 43210, USA, Tel: 614-293-3392, Fax: 614-292-6087, E-mail:
| | - Jonathan P Godbout
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA,Department of Neuroscience, The Ohio State University, Columbus, OH, USA
| | - John F Sheridan
- Division of Biosciences, The Ohio State University, Columbus, OH, USA,Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, OH, USA,Institute for Behavioral Medicine Research, The Ohio State University, Columbus, OH, USA
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27
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De Lucia C, Rinchon A, Olmos-Alonso A, Riecken K, Fehse B, Boche D, Perry VH, Gomez-Nicola D. Microglia regulate hippocampal neurogenesis during chronic neurodegeneration. Brain Behav Immun 2016; 55:179-190. [PMID: 26541819 PMCID: PMC4907582 DOI: 10.1016/j.bbi.2015.11.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 10/22/2015] [Accepted: 11/01/2015] [Indexed: 12/22/2022] Open
Abstract
Neurogenesis is altered in neurodegenerative disorders, partly regulated by inflammatory factors. We have investigated whether microglia, the innate immune brain cells, regulate hippocampal neurogenesis in neurodegeneration. Using the ME7 model of prion disease we applied gain- or loss-of CSF1R function, as means to stimulate or inhibit microglial proliferation, respectively, to dissect the contribution of these cells to neurogenesis. We found that increased hippocampal neurogenesis correlates with the expansion of the microglia population. The selective inhibition of microglial proliferation caused a reduction in neurogenesis and a restoration of normal neuronal differentiation, supporting a pro-neurogenic role for microglia. Using a gene screening strategy, we identified TGFβ as a molecule controlling the microglial pro-neurogenic response in chronic neurodegeneration, supported by loss-of-function mechanistic experiments. By the selective targeting of microglial proliferation we have been able to uncover a pro-neurogenic role for microglia in chronic neurodegeneration, suggesting promising therapeutic targets to normalise the neurogenic niche during neurodegeneration.
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Affiliation(s)
- Chiara De Lucia
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Adeline Rinchon
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Adrian Olmos-Alonso
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Kristoffer Riecken
- Research Department Cell and Gene Therapy, Clinic for Stem Cell Transplantation, University Medical Centre (UMC) Hamburg-Eppendorf, Hamburg, Germany
| | - Boris Fehse
- Research Department Cell and Gene Therapy, Clinic for Stem Cell Transplantation, University Medical Centre (UMC) Hamburg-Eppendorf, Hamburg, Germany
| | - Delphine Boche
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, United Kingdom
| | - V. Hugh Perry
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Diego Gomez-Nicola
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom.
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28
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Tay TL, Savage JC, Hui CW, Bisht K, Tremblay MÈ. Microglia across the lifespan: from origin to function in brain development, plasticity and cognition. J Physiol 2016; 595:1929-1945. [PMID: 27104646 DOI: 10.1113/jp272134] [Citation(s) in RCA: 352] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 03/15/2016] [Indexed: 12/11/2022] Open
Abstract
Microglia are the only immune cells that permanently reside in the central nervous system (CNS) alongside neurons and other types of glial cells. The past decade has witnessed a revolution in our understanding of their roles during normal physiological conditions. Cutting-edge techniques revealed that these resident immune cells are critical for proper brain development, actively maintain health in the mature brain, and rapidly adapt their function to physiological or pathophysiological needs. In this review, we highlight recent studies on microglial origin (from the embryonic yolk sac) and the factors regulating their differentiation and homeostasis upon brain invasion. Elegant experiments tracking microglia in the CNS allowed studies of their unique roles compared with other types of resident macrophages. Here we review the emerging roles of microglia in brain development, plasticity and cognition, and discuss the implications of the depletion or dysfunction of microglia for our understanding of disease pathogenesis. Immune activation, inflammation and various other conditions resulting in undesirable microglial activity at different stages of life could severely impair learning, memory and other essential cognitive functions. The diversity of microglial phenotypes across the lifespan, between compartments of the CNS, and sexes, as well as their crosstalk with the body and external environment, is also emphasised. Understanding what defines particular microglial phenotypes is of major importance for future development of innovative therapies controlling their effector functions, with consequences for cognition across chronic stress, ageing, neuropsychiatric and neurological diseases.
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Affiliation(s)
- Tuan Leng Tay
- Institute of Neuropathology, University of Freiburg, Germany
| | - Julie C Savage
- Axe Neurosciences, Centre de recherche du CHU de Québec, Québec, Canada
| | - Chin Wai Hui
- Axe Neurosciences, Centre de recherche du CHU de Québec, Québec, Canada
| | - Kanchan Bisht
- Axe Neurosciences, Centre de recherche du CHU de Québec, Québec, Canada
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29
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Abiega O, Beccari S, Diaz-Aparicio I, Nadjar A, Layé S, Leyrolle Q, Gómez-Nicola D, Domercq M, Pérez-Samartín A, Sánchez-Zafra V, Paris I, Valero J, Savage JC, Hui CW, Tremblay MÈ, Deudero JJP, Brewster AL, Anderson AE, Zaldumbide L, Galbarriatu L, Marinas A, Vivanco MDM, Matute C, Maletic-Savatic M, Encinas JM, Sierra A. Neuronal Hyperactivity Disturbs ATP Microgradients, Impairs Microglial Motility, and Reduces Phagocytic Receptor Expression Triggering Apoptosis/Microglial Phagocytosis Uncoupling. PLoS Biol 2016; 14:e1002466. [PMID: 27228556 PMCID: PMC4881984 DOI: 10.1371/journal.pbio.1002466] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 04/21/2016] [Indexed: 12/24/2022] Open
Abstract
Phagocytosis is essential to maintain tissue homeostasis in a large number of inflammatory and autoimmune diseases, but its role in the diseased brain is poorly explored. Recent findings suggest that in the adult hippocampal neurogenic niche, where the excess of newborn cells undergo apoptosis in physiological conditions, phagocytosis is efficiently executed by surveillant, ramified microglia. To test whether microglia are efficient phagocytes in the diseased brain as well, we confronted them with a series of apoptotic challenges and discovered a generalized response. When challenged with excitotoxicity in vitro (via the glutamate agonist NMDA) or inflammation in vivo (via systemic administration of bacterial lipopolysaccharides or by omega 3 fatty acid deficient diets), microglia resorted to different strategies to boost their phagocytic efficiency and compensate for the increased number of apoptotic cells, thus maintaining phagocytosis and apoptosis tightly coupled. Unexpectedly, this coupling was chronically lost in a mouse model of mesial temporal lobe epilepsy (MTLE) as well as in hippocampal tissue resected from individuals with MTLE, a major neurological disorder characterized by seizures, excitotoxicity, and inflammation. Importantly, the loss of phagocytosis/apoptosis coupling correlated with the expression of microglial proinflammatory, epileptogenic cytokines, suggesting its contribution to the pathophysiology of epilepsy. The phagocytic blockade resulted from reduced microglial surveillance and apoptotic cell recognition receptor expression and was not directly mediated by signaling through microglial glutamate receptors. Instead, it was related to the disruption of local ATP microgradients caused by the hyperactivity of the hippocampal network, at least in the acute phase of epilepsy. Finally, the uncoupling led to an accumulation of apoptotic newborn cells in the neurogenic niche that was due not to decreased survival but to delayed cell clearance after seizures. These results demonstrate that the efficiency of microglial phagocytosis critically affects the dynamics of apoptosis and urge to routinely assess the microglial phagocytic efficiency in neurodegenerative disorders. Phagocytosis by microglia is tightly coupled to apoptosis, swiftly removing apoptotic cells and actively maintaining tissue homeostasis, but the neuronal hyperactivity associated with epilepsy disrupts the ATP gradients that drive phagocytosis, leading to the accumulation of apoptotic cells and inflammation. Phagocytosis, the engulfment and digestion of cellular debris, is at the core of the regenerative response of the damaged tissue, because it prevents the spillover of toxic intracellular contents and is actively anti-inflammatory. In the brain, the professional phagocytes are microglia, whose dynamic processes rapidly engulf and degrade cells undergoing apoptosis—programmed cell death—in physiological conditions. Thus, microglia hold the key to brain regeneration, but their efficiency as phagocytes in the diseased brain is only presumed. Here, we have discovered a generalized response of microglia to apoptotic challenge induced by excitotoxicity and inflammation, in which they boost their phagocytic efficiency to account for the increase in apoptosis. To our surprise, this apoptosis/microglial phagocytosis coupling was lost in the hippocampus from human and experimental mesial temporal lobe epilepsy (MTLE), a major neurodegenerative disorder characterized by excitotoxicity, inflammation, and seizures. This uncoupling was due to widespread ATP release during neuronal hyperactivity, which “blinded” microglia to the ATP microgradients released by apoptotic cells as “find-me” signals. The impairment of phagocytosis led to the accumulation of apoptotic cells and the build-up of a detrimental inflammatory reaction. Our data advocates for systematic assessment of the efficiency of microglial phagocytosis in brain disorders.
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Affiliation(s)
- Oihane Abiega
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | - Sol Beccari
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | - Irune Diaz-Aparicio
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | | | - Sophie Layé
- Université Bordeaux Segalen, Bordeaux, France
| | | | - Diego Gómez-Nicola
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - María Domercq
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | - Alberto Pérez-Samartín
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | - Víctor Sánchez-Zafra
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | - Iñaki Paris
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | - Jorge Valero
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
- Ikerbasque Foundation, Bilbao, Spain
| | - Julie C. Savage
- Centre de recherche du CHU de Québec, Axe Neurosciences, Québec, Canada
- Université Laval, Département de médecine moléculaire, Québec, Canada
| | - Chin-Wai Hui
- Centre de recherche du CHU de Québec, Axe Neurosciences, Québec, Canada
- Université Laval, Département de médecine moléculaire, Québec, Canada
| | - Marie-Ève Tremblay
- Centre de recherche du CHU de Québec, Axe Neurosciences, Québec, Canada
- Université Laval, Département de médecine moléculaire, Québec, Canada
| | - Juan J. P. Deudero
- Baylor College of Medicine, The Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, Texas, United States of America
| | - Amy L. Brewster
- Baylor College of Medicine, The Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, Texas, United States of America
| | - Anne E. Anderson
- Baylor College of Medicine, The Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, Texas, United States of America
| | | | | | | | | | - Carlos Matute
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
| | | | - Juan M. Encinas
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
- Baylor College of Medicine, The Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, Texas, United States of America
| | - Amanda Sierra
- Achucarro Basque Center for Neuroscience, Bizkaia Science and Technology Park, Zamudio, Spain
- University of the Basque Country, Leioa, Spain
- Baylor College of Medicine, The Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, Texas, United States of America
- * E-mail:
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30
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Zhu C, Herrmann US, Falsig J, Abakumova I, Nuvolone M, Schwarz P, Frauenknecht K, Rushing EJ, Aguzzi A. A neuroprotective role for microglia in prion diseases. J Exp Med 2016; 213:1047-59. [PMID: 27185853 PMCID: PMC4886355 DOI: 10.1084/jem.20151000] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 04/05/2016] [Indexed: 12/04/2022] Open
Abstract
Microglial activation is a hallmark of most neurodegenerative disorders, yet it is not clear if it plays beneficial or deleterious roles. Zhu et al. provide evidence for a general protective role of microglia in the pathogenesis of prion diseases. Microglial activation is a hallmark of most neurodegenerative disorders, and is particularly conspicuous in prion diseases. However, the role of microglia, which function as both primary immune effector cells and professional phagocytes in the central nervous system, remains contentious in the context of neurodegeneration. Here, we evaluated the effect of microglial depletion/deficiency on prion pathogenesis. We found that ganciclovir-mediated microglial ablation on tga20/CD11b-thymidine kinase of Herpes simplex virus (HSVTK) cerebellar organotypic cultured slices markedly aggravated prion-induced neurotoxicity. A similar deterioration of disease was recapitulated in in vivo microglial depletion in prion-infected tga20/CD11b-HSVTK mice. Additionally, deficiency of microglia in interleukin 34 knockout (IL34−/−) mice again resulted in significantly augmented proteinase K–resistant prion protein deposition and accelerated prion disease progression. These results provide unambiguous evidence for a general protective role of microglia in prion pathogenesis.
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Affiliation(s)
- Caihong Zhu
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Uli S Herrmann
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Jeppe Falsig
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Irina Abakumova
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Mario Nuvolone
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Petra Schwarz
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Katrin Frauenknecht
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Elisabeth J Rushing
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital Zurich, 8091 Zurich, Switzerland
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31
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Kang SG, Kim C, Cortez LM, Carmen Garza M, Yang J, Wille H, Sim VL, Westaway D, McKenzie D, Aiken J. Toll-like receptor-mediated immune response inhibits prion propagation. Glia 2016; 64:937-51. [PMID: 26880394 DOI: 10.1002/glia.22973] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 01/12/2016] [Accepted: 01/14/2016] [Indexed: 02/03/2023]
Abstract
Prion diseases are progressive neurodegenerative disorders affecting humans and various mammals. The prominent neuropathological change in prion diseases is neuroinflammation characterized by activation of neuroglia surrounding prion deposition. The cause and effect of this cellular response, however, is unclear. We investigated innate immune defenses against prion infection using primary mixed neuronal and glial cultures. Conditional prion propagation occurred in glial cultures depending on their immune status. Preconditioning of the cells with the toll-like receptor (TLR) ligand, lipopolysaccharide, resulted in a reduction in prion propagation, whereas suppression of the immune responses with the synthetic glucocorticoid, dexamethasone, increased prion propagation. In response to recombinant prion fibrils, glial cells up-regulated TLRs (TLR1 and TLR2) expression and secreted cytokines (tumor necrosis factor-α, interleukin-1β, interleukin-6, granulocyte-macrophage colony-stimulating factor, and interferon-β). Preconditioning of neuronal and glial cultures with recombinant prion fibrils inhibited prion replication and altered microglial and astrocytic populations. Our results provide evidence that, in early stages of prion infection, glial cells respond to prion infection through TLR-mediated innate immunity.
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Affiliation(s)
- Sang-Gyun Kang
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Chiye Kim
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Leonardo M Cortez
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - María Carmen Garza
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Jing Yang
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Holger Wille
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Valerie L Sim
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - David Westaway
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada.,Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Debbie McKenzie
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Judd Aiken
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Department of Agricultural, Food, and Nutritional Sciences, University of Alberta, Edmonton, Alberta, Canada
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32
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Bisht K, Sharma KP, Lecours C, Sánchez MG, El Hajj H, Milior G, Olmos-Alonso A, Gómez-Nicola D, Luheshi G, Vallières L, Branchi I, Maggi L, Limatola C, Butovsky O, Tremblay MÈ. Dark microglia: A new phenotype predominantly associated with pathological states. Glia 2016; 64:826-39. [PMID: 26847266 PMCID: PMC4949554 DOI: 10.1002/glia.22966] [Citation(s) in RCA: 270] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/06/2015] [Accepted: 12/28/2015] [Indexed: 12/24/2022]
Abstract
The past decade has witnessed a revolution in our understanding of microglia. These immune cells were shown to actively remodel neuronal circuits, leading to propose new pathogenic mechanisms. To study microglial implication in the loss of synapses, the best pathological correlate of cognitive decline across chronic stress, aging, and diseases, we recently conducted ultrastructural analyses. Our work uncovered the existence of a new microglial phenotype that is rarely present under steady state conditions, in hippocampus, cerebral cortex, amygdala, and hypothalamus, but becomes abundant during chronic stress, aging, fractalkine signaling deficiency (CX3 CR1 knockout mice), and Alzheimer's disease pathology (APP-PS1 mice). Even though these cells display ultrastructural features of microglia, they are strikingly distinct from the other phenotypes described so far at the ultrastructural level. They exhibit several signs of oxidative stress, including a condensed, electron-dense cytoplasm and nucleoplasm making them as "dark" as mitochondria, accompanied by a pronounced remodeling of their nuclear chromatin. Dark microglia appear to be much more active than the normal microglia, reaching for synaptic clefts, while extensively encircling axon terminals and dendritic spines with their highly ramified and thin processes. They stain for the myeloid cell markers IBA1 and GFP (in CX3 CR1-GFP mice), and strongly express CD11b and microglia-specific 4D4 in their processes encircling synaptic elements, and TREM2 when they associate with amyloid plaques. Overall, these findings suggest that dark microglia, a new phenotype that we identified based on their unique properties, could play a significant role in the pathological remodeling of neuronal circuits, especially at synapses.
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Affiliation(s)
- Kanchan Bisht
- Axe Neurosciences, Centre De Recherche Du CHU De Québec, Québec, Québec, Canada
| | - Kaushik P Sharma
- Axe Neurosciences, Centre De Recherche Du CHU De Québec, Québec, Québec, Canada
| | - Cynthia Lecours
- Axe Neurosciences, Centre De Recherche Du CHU De Québec, Québec, Québec, Canada
| | | | - Hassan El Hajj
- Axe Neurosciences, Centre De Recherche Du CHU De Québec, Québec, Québec, Canada
| | - Giampaolo Milior
- Department of Physiology and Pharmacology, Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Adrián Olmos-Alonso
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Diego Gómez-Nicola
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Giamal Luheshi
- Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Québec, Canada
| | - Luc Vallières
- Axe Neurosciences, Centre De Recherche Du CHU De Québec, Québec, Québec, Canada
| | - Igor Branchi
- Section of Behavioural Neurosciences, Department of Cell Biology and Neurosciences, Istituto Superiore Di Sanità, Rome, Italy
| | - Laura Maggi
- Department of Physiology and Pharmacology, Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Cristina Limatola
- Department of Physiology and Pharmacology, Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza University of Rome, Rome, Italy
| | - Oleg Butovsky
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre De Recherche Du CHU De Québec, Québec, Québec, Canada
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33
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Orihuela R, McPherson CA, Harry GJ. Microglial M1/M2 polarization and metabolic states. Br J Pharmacol 2016; 173:649-65. [PMID: 25800044 PMCID: PMC4742299 DOI: 10.1111/bph.13139] [Citation(s) in RCA: 1195] [Impact Index Per Article: 149.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 03/05/2015] [Accepted: 03/13/2015] [Indexed: 02/06/2023] Open
Abstract
Microglia are critical nervous system-specific immune cells serving as tissue-resident macrophages influencing brain development, maintenance of the neural environment, response to injury and repair. As influenced by their environment, microglia assume a diversity of phenotypes and retain the capability to shift functions to maintain tissue homeostasis. In comparison with peripheral macrophages, microglia demonstrate similar and unique features with regards to phenotype polarization, allowing for innate immunological functions. Microglia can be stimulated by LPS or IFN-γ to an M1 phenotype for expression of pro-inflammatory cytokines or by IL-4/IL-13 to an M2 phenotype for resolution of inflammation and tissue repair. Increasing evidence suggests a role of metabolic reprogramming in the regulation of the innate inflammatory response. Studies using peripheral immune cells demonstrate that polarization to an M1 phenotype is often accompanied by a shift in cells from oxidative phosphorylation to aerobic glycolysis for energy production. More recently, the link between polarization and mitochondrial energy metabolism has been considered in microglia. Under these conditions, energy demands would be associated with functional activities and cell survival and thus, may serve to influence the contribution of microglia activation to various neurodegenerative conditions. This review examines the polarization states of microglia and their relationship to mitochondrial metabolism. Additional supporting experimental data are provided to demonstrate mitochondrial metabolic shifts in primary microglia and the BV-2 microglia cell line induced under LPS (M1) and IL-4/IL-13 (M2) polarization.
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Affiliation(s)
- Ruben Orihuela
- Neurotoxicology Group, National Toxicology Program Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Christopher A McPherson
- Neurotoxicology Group, National Toxicology Program Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Gaylia Jean Harry
- Neurotoxicology Group, National Toxicology Program Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
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34
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Olmos-Alonso A, Schetters STT, Sri S, Askew K, Mancuso R, Vargas-Caballero M, Holscher C, Perry VH, Gomez-Nicola D. Pharmacological targeting of CSF1R inhibits microglial proliferation and prevents the progression of Alzheimer's-like pathology. Brain 2016; 139:891-907. [PMID: 26747862 PMCID: PMC4766375 DOI: 10.1093/brain/awv379] [Citation(s) in RCA: 295] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 10/29/2015] [Indexed: 01/24/2023] Open
Abstract
The proliferation and activation of microglial cells is a hallmark of several neurodegenerative conditions. This mechanism is regulated by the activation of the colony-stimulating factor 1 receptor (CSF1R), thus providing a target that may prevent the progression of conditions such as Alzheimer’s disease. However, the study of microglial proliferation in Alzheimer’s disease and validation of the efficacy of CSF1R-inhibiting strategies have not yet been reported. In this study we found increased proliferation of microglial cells in human Alzheimer’s disease, in line with an increased upregulation of the CSF1R-dependent pro-mitogenic cascade, correlating with disease severity. Using a transgenic model of Alzheimer’s-like pathology (APPswe, PSEN1dE9; APP/PS1 mice) we define a CSF1R-dependent progressive increase in microglial proliferation, in the proximity of amyloid-β plaques. Prolonged inhibition of CSF1R in APP/PS1 mice by an orally available tyrosine kinase inhibitor (GW2580) resulted in the blockade of microglial proliferation and the shifting of the microglial inflammatory profile to an anti-inflammatory phenotype. Pharmacological targeting of CSF1R in APP/PS1 mice resulted in an improved performance in memory and behavioural tasks and a prevention of synaptic degeneration, although these changes were not correlated with a change in the number of amyloid-β plaques. Our results provide the first proof of the efficacy of CSF1R inhibition in models of Alzheimer’s disease, and validate the application of a therapeutic strategy aimed at modifying CSF1R activation as a promising approach to tackle microglial activation and the progression of Alzheimer’s disease.
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Affiliation(s)
- Adrian Olmos-Alonso
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | | | - Sarmi Sri
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Katharine Askew
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Renzo Mancuso
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Mariana Vargas-Caballero
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK 2 Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Christian Holscher
- 3 Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YQ, UK
| | - V Hugh Perry
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Diego Gomez-Nicola
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
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The Good, the Bad, and the Ugly of Dendritic Cells during Prion Disease. J Immunol Res 2015; 2015:168574. [PMID: 26697507 PMCID: PMC4677227 DOI: 10.1155/2015/168574] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 11/15/2015] [Indexed: 12/11/2022] Open
Abstract
Prions are a unique group of proteinaceous pathogens which cause neurodegenerative disease and can be transmitted by a variety of exposure routes. After peripheral exposure, the accumulation and replication of prions within secondary lymphoid organs are obligatory for their efficient spread from the periphery to the brain where they ultimately cause neurodegeneration and death. Mononuclear phagocytes (MNP) are a heterogeneous population of dendritic cells (DC) and macrophages. These cells are abundant throughout the body and display a diverse range of roles based on their anatomical locations. For example, some MNP are strategically situated to provide a first line of defence against pathogens by phagocytosing and destroying them. Conventional DC are potent antigen presenting cells and migrate via the lymphatics to the draining lymphoid tissue where they present the antigens to lymphocytes. The diverse roles of MNP are also reflected in various ways in which they interact with prions and in doing so impact on disease pathogenesis. Indeed, some studies suggest that prions exploit conventional DC to infect the host. Here we review our current understanding of the influence of MNP in the pathogenesis of the acquired prion diseases with particular emphasis on the role of conventional DC.
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Zaru R, Matthews SP, Edgar AJ, Prescott AR, Gomez-Nicola D, Hanauer A, Watts C. The PDK1-Rsk Signaling Pathway Controls Langerhans Cell Proliferation and Patterning. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2015; 195:4264-72. [PMID: 26401001 PMCID: PMC4640173 DOI: 10.4049/jimmunol.1501520] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 08/26/2015] [Indexed: 12/12/2022]
Abstract
Langerhans cells (LC), the dendritic cells of the epidermis, are distributed in a distinctive regularly spaced array. In the mouse, the LC array is established in the first few days of life from proliferating local precursors, but the regulating signaling pathways are not fully understood. We found that mice lacking the kinase phosphoinositide-dependent kinase 1 selectively lack LC. Deletion of the phosphoinositide-dependent kinase 1 target kinases, ribosomal S6 kinase 1 (Rsk1) and Rsk2, produced a striking perturbation in the LC network: LC density was reduced 2-fold, but LC size was increased by the same magnitude. Reduced LC numbers in Rsk1/2(-/-) mice was not due to accelerated emigration from the skin but rather to reduced proliferation at least in adults. Rsk1/2 were required for normal LC patterning in neonates, but not when LC were ablated in adults and replaced by bone marrow-derived cells. Increased LC size was an intrinsic response to reduced LC numbers, reversible on LC emigration, and could be observed in wild type epidermis where LC size also correlated inversely with LC density. Our results identify a key signaling pathway needed to establish a normal LC network and suggest that LC might maintain epidermal surveillance by increasing their "footprint" when their numbers are limited.
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Affiliation(s)
- Rossana Zaru
- Division of Cell Signaling and Immunology, College of Life Science, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Stephen P Matthews
- Division of Cell Signaling and Immunology, College of Life Science, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Alexander J Edgar
- Division of Cell Signaling and Immunology, College of Life Science, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Alan R Prescott
- Division of Cell Signaling and Immunology, College of Life Science, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Diego Gomez-Nicola
- Centre for Biological Sciences, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - André Hanauer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique Unite Mixté de Recherche 7104, INSERM U 964, University of Strasbourg, 67404 Illkirch, France
| | - Colin Watts
- Division of Cell Signaling and Immunology, College of Life Science, University of Dundee, Dundee DD1 5EH, United Kingdom;
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Abstract
The past two decades of research into the pathogenesis of Alzheimer disease (AD) have been driven largely by the amyloid hypothesis; the neuroinflammation that is associated with AD has been assumed to be merely a response to pathophysiological events. However, new data from preclinical and clinical studies have established that immune system-mediated actions in fact contribute to and drive AD pathogenesis. These insights have suggested both novel and well-defined potential therapeutic targets for AD, including microglia and several cytokines. In addition, as inflammation in AD primarily concerns the innate immune system - unlike in 'typical' neuroinflammatory diseases such as multiple sclerosis and encephalitides - the concept of neuroinflammation in AD may need refinement.
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Gomez-Nicola D, Boche D. Post-mortem analysis of neuroinflammatory changes in human Alzheimer's disease. Alzheimers Res Ther 2015; 7:42. [PMID: 25904988 PMCID: PMC4405851 DOI: 10.1186/s13195-015-0126-1] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Since the genome-wide association studies in Alzheimer's disease have highlighted inflammation as a driver of the disease rather than a consequence of the ongoing neurodegeneration, numerous studies have been performed to identify specific immune profiles associated with healthy, ageing, or diseased brain. However, these studies have been performed mainly in in vitro or animal models, which recapitulate only some aspects of the pathophysiology of human Alzheimer's disease. In this review, we discuss the availability of human post-mortem tissue through brain banks, the limitations associated with its use, the technical tools available, and the neuroimmune aspects to explore in order to validate in the human brain the experimental observations arising from animal models.
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Affiliation(s)
- Diego Gomez-Nicola
- />Centre for Biological Sciences, Faculty of Natural and Environmental Sciences, University of Southampton, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD UK
| | - Delphine Boche
- />Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD UK
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Gomez-Nicola D, Riecken K, Fehse B, Perry VH. In-vivo RGB marking and multicolour single-cell tracking in the adult brain. Sci Rep 2014; 4:7520. [PMID: 25531807 PMCID: PMC4273606 DOI: 10.1038/srep07520] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 11/27/2014] [Indexed: 12/31/2022] Open
Abstract
In neuroscience it is a technical challenge to identify and follow the temporal and spatial distribution of cells as they differentiate. We hypothesised that RGB marking, the tagging of individual cells with unique hues resulting from simultaneous expression of the three basic colours red, green and blue, provides a convenient toolbox for the study of the CNS anatomy at the single-cell level. Using γ-retroviral and lentiviral vector sets we describe for the first time the in-vivo multicolour RGB marking of neurons in the adult brain. RGB marking also enabled us to track the spatial and temporal fate of neural stem cells in the adult brain. The application of different viral envelopes and promoters provided a useful approach to track the generation of neurons vs. glial cells at the neurogenic niche, allowing the identification of the prominent generation of new astrocytes to the striatum. Multicolour RGB marking could serve as a universal and reproducible method to study and manipulate the CNS at the single-cell level, in both health and disease.
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Affiliation(s)
- Diego Gomez-Nicola
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
| | - Kristoffer Riecken
- Research Department Cell and Gene Therapy, Clinic for Stem Cell Transplantation, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Boris Fehse
- Research Department Cell and Gene Therapy, Clinic for Stem Cell Transplantation, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - V. Hugh Perry
- Centre for Biological Sciences, University of Southampton, Southampton, United Kingdom
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Gomez-Nicola D, Suzzi S, Vargas-Caballero M, Fransen NL, Al-Malki H, Cebrian-Silla A, Garcia-Verdugo JM, Riecken K, Fehse B, Perry VH. Temporal dynamics of hippocampal neurogenesis in chronic neurodegeneration. ACTA ACUST UNITED AC 2014; 137:2312-28. [PMID: 24941947 PMCID: PMC4107745 DOI: 10.1093/brain/awu155] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Increased neurogenesis has been reported in neurodegenerative disease, but its significance is unclear. In a mouse model of prion disease, Gomez-Nicola et al. detect increased neurogenesis in the dentate gyrus that partially counteracts neuronal loss. Targeting neurogenesis may have therapeutic potential. The study of neurogenesis during chronic neurodegeneration is crucial in order to understand the intrinsic repair mechanisms of the brain, and key to designing therapeutic strategies. In this study, using an experimental model of progressive chronic neurodegeneration, murine prion disease, we define the temporal dynamics of the generation, maturation and integration of new neurons in the hippocampal dentate gyrus, using dual pulse-chase, multicolour γ-retroviral tracing, transmission electron microscopy and patch-clamp. We found increased neurogenesis during the progression of prion disease, which partially counteracts the effects of chronic neurodegeneration, as evidenced by blocking neurogenesis with cytosine arabinoside, and helps to preserve the hippocampal function. Evidence obtained from human post-mortem samples, of both variant Creutzfeldt-Jakob disease and Alzheimer’s disease patients, also suggests increased neurogenic activity. These results open a new avenue into the exploration of the effects and regulation of neurogenesis during chronic neurodegeneration, and offer a new model to reproduce the changes observed in human neurodegenerative diseases.
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Affiliation(s)
- Diego Gomez-Nicola
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Stefano Suzzi
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Mariana Vargas-Caballero
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Nina L Fransen
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Hussain Al-Malki
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | | | | | - Kristoffer Riecken
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - Boris Fehse
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - V Hugh Perry
- 1 Centre for Biological Sciences, University of Southampton, Southampton, UK
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Rivera-Escalera F, Matousek SB, Ghosh S, Olschowka JA, O'Banion MK. Interleukin-1β mediated amyloid plaque clearance is independent of CCR2 signaling in the APP/PS1 mouse model of Alzheimer's disease. Neurobiol Dis 2014; 69:124-33. [PMID: 24874542 DOI: 10.1016/j.nbd.2014.05.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/09/2014] [Accepted: 05/17/2014] [Indexed: 12/29/2022] Open
Abstract
Neuroinflammation is a key component of Alzheimer's disease (AD) pathogenesis. Particularly, the proinflammatory cytokine interleukin-1 beta (IL-1β) is upregulated in human AD and believed to promote amyloid plaque deposition. However, studies from our laboratory have shown that chronic IL-1β overexpression in the APPswe/PSEN1dE9 (APP/PS1) mouse model of AD ameliorates amyloid pathology, increases plaque-associated microglia, and induces recruitment of peripheral immune cells to the brain parenchyma. To investigate the contribution of CCR2 signaling in IL-1β-mediated amyloid plaque clearance, seven month-old APP/PS1/CCR2(-/-) mice were intrahippocampally transduced with a recombinant adeno-associated virus serotype 2 containing the cleaved form of human IL-1β (rAAV2-IL-1β). Four weeks after rAAV2-IL-1β transduction, we found significant reductions in 6E10 and Congo red staining of amyloid plaques that was confirmed by decreased levels of insoluble Aβ1-42 and Aβ1-40 in the inflamed hippocampus. Bone marrow chimeric studies confirmed the presence of infiltrating immune cells following IL-1β overexpression and revealed that dramatic reduction of CCR2(+) peripheral mononuclear cell recruitment to the inflamed hippocampus did not prevent the ability of IL-1β to induce amyloid plaque clearance. These results suggest that infiltrating CCR2(+) monocytes do not contribute to IL-1β-mediated amyloid plaque clearance.
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Affiliation(s)
- Fátima Rivera-Escalera
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Sarah B Matousek
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Simantini Ghosh
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - John A Olschowka
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - M Kerry O'Banion
- Department of Neurobiology and Anatomy, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
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Gomez-Nicola D, Perry VH. Microglial dynamics and role in the healthy and diseased brain: a paradigm of functional plasticity. Neuroscientist 2014; 21:169-84. [PMID: 24722525 PMCID: PMC4412879 DOI: 10.1177/1073858414530512] [Citation(s) in RCA: 219] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The study of the dynamics and functions of microglia in the healthy and diseased brain is a matter of intense scientific activity. The application of new techniques and new experimental approaches has allowed the identification of novel microglial functions and the redefinition of classic ones. In this review, we propose the study of microglial functions, rather than their molecular profiles, to better understand and define the roles of these cells in the brain. We review current knowledge on the role of surveillant microglia, proliferating microglia, pruning/neuromodulatory microglia, phagocytic microglia, and inflammatory microglia and the molecular profiles that are associated with these functions. In the remodeling scenario of microglial biology, the analysis of microglial functional states will inform about the roles in health and disease and will guide us to a more precise understanding of the multifaceted roles of this never-resting cells.
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Affiliation(s)
- Diego Gomez-Nicola
- Centre for Biological Sciences, University of Southampton, Southampton, UK
| | - V Hugh Perry
- Centre for Biological Sciences, University of Southampton, Southampton, UK
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