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Syage AR, Pachow C, Murray KM, Henningfield C, Fernandez K, Du A, Cheng Y, Olivarria G, Kawauchi S, MacGregor GR, Green KN, Lane TE. Cystatin F attenuates neuroinflammation and demyelination following murine coronavirus infection of the central nervous system. J Neuroinflammation 2024; 21:157. [PMID: 38879499 PMCID: PMC11179388 DOI: 10.1186/s12974-024-03153-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 06/12/2024] [Indexed: 06/19/2024] Open
Abstract
BACKGROUND Cystatin F is a secreted lysosomal cysteine protease inhibitor that has been implicated in affecting the severity of demyelination and enhancing remyelination in pre-clinical models of immune-mediated demyelination. How cystatin F impacts neurologic disease severity following viral infection of the central nervous system (CNS) has not been well characterized and was the focus of this study. We used cystatin F null-mutant mice (Cst7-/-) with a well-established model of murine coronavirus-induced neurologic disease to evaluate the contributions of cystatin F in host defense, demyelination and remyelination. METHODS Wildtype controls and Cst7-/- mice were intracranially (i.c.) infected with a sublethal dose of the neurotropic JHM strain of mouse hepatitis virus (JHMV), with disease progression and survival monitored daily. Viral plaque assays and qPCR were used to assess viral levels in CNS. Immune cell infiltration into the CNS and immune cell activation were determined by flow cytometry and 10X genomics chromium 3' single cell RNA sequencing (scRNA-seq). Spinal cord demyelination was determined by luxol fast blue (LFB) and Hematoxylin/Eosin (H&E) staining and axonal damage assessed by immunohistochemical staining for SMI-32. Remyelination was evaluated by electron microscopy (EM) and calculation of g-ratios. RESULTS JHMV-infected Cst7-/- mice were able to control viral replication within the CNS, indicating that cystatin F is not essential for an effective Th1 anti-viral immune response. Infiltration of T cells into the spinal cords of JHMV-infected Cst7-/- mice was increased compared to infected controls, and this correlated with increased axonal damage and demyelination associated with impaired remyelination. Single-cell RNA-seq of CD45 + cells enriched from spinal cords of infected Cst7-/- and control mice revealed enhanced expression of transcripts encoding T cell chemoattractants, Cxcl9 and Cxcl10, combined with elevated expression of interferon-g (Ifng) and perforin (Prf1) transcripts in CD8 + T cells from Cst7-/- mice compared to controls. CONCLUSIONS Cystatin F is not required for immune-mediated control of JHMV replication within the CNS. However, JHMV-infected Cst7-/- mice exhibited more severe clinical disease associated with increased demyelination and impaired remyelination. The increase in disease severity was associated with elevated expression of T cell chemoattractant chemokines, concurrent with increased neuroinflammation. These findings support the idea that cystatin F influences expression of proinflammatory gene expression impacting neuroinflammation, T cell activation and/or glia cell responses ultimately impacting neuroinflammation and neurologic disease.
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Affiliation(s)
- Amber R Syage
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Collin Pachow
- Department of Molecular Biology & Biochemistry, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Kaitlin M Murray
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Caden Henningfield
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Kellie Fernandez
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Annie Du
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Yuting Cheng
- Department of Molecular Biology & Biochemistry, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Gema Olivarria
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Shimako Kawauchi
- Transgenic Mouse Facility, ULAR, Office of Research, University of California, Irvine, 92697, USA
| | - Grant R MacGregor
- Department of Developmental & Cell Biology, University of California, Irvine, 92697, USA
| | - Kim N Green
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA
| | - Thomas E Lane
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine, 92697, USA.
- Center for Virus Research, University of California, Irvine, 92697, USA.
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DePaula-Silva AB. The Contribution of Microglia and Brain-Infiltrating Macrophages to the Pathogenesis of Neuroinflammatory and Neurodegenerative Diseases during TMEV Infection of the Central Nervous System. Viruses 2024; 16:119. [PMID: 38257819 PMCID: PMC10819099 DOI: 10.3390/v16010119] [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: 12/05/2023] [Revised: 01/06/2024] [Accepted: 01/09/2024] [Indexed: 01/24/2024] Open
Abstract
The infection of the central nervous system (CNS) with neurotropic viruses induces neuroinflammation and is associated with the development of neuroinflammatory and neurodegenerative diseases, including multiple sclerosis and epilepsy. The activation of the innate and adaptive immune response, including microglial, macrophages, and T and B cells, while required for efficient viral control within the CNS, is also associated with neuropathology. Under healthy conditions, resident microglia play a pivotal role in maintaining CNS homeostasis. However, during pathological events, such as CNS viral infection, microglia become reactive, and immune cells from the periphery infiltrate into the brain, disrupting CNS homeostasis and contributing to disease development. Theiler's murine encephalomyelitis virus (TMEV), a neurotropic picornavirus, is used in two distinct mouse models: TMEV-induced demyelination disease (TMEV-IDD) and TMEV-induced seizures, representing mouse models of multiple sclerosis and epilepsy, respectively. These murine models have contributed substantially to our understanding of the pathophysiology of MS and seizures/epilepsy following viral infection, serving as critical tools for identifying pharmacological targetable pathways to modulate disease development. This review aims to discuss the host-pathogen interaction during a neurotropic picornavirus infection and to shed light on our current understanding of the multifaceted roles played by microglia and macrophages in the context of these two complexes viral-induced disease.
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Affiliation(s)
- Ana Beatriz DePaula-Silva
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT 84112, USA
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Cheng Y, Javonillo DI, Pachow C, Scarfone VM, Fernandez K, Walsh CM, Green KN, Lane TE. Ablation of microglia following infection of the central nervous system with a neurotropic murine coronavirus infection leads to increased demyelination and impaired remyelination. J Neuroimmunol 2023; 381:578133. [PMID: 37352687 DOI: 10.1016/j.jneuroim.2023.578133] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/12/2023] [Accepted: 06/15/2023] [Indexed: 06/25/2023]
Abstract
Intracranial inoculation of susceptible mice with a glial-tropic strain of mouse hepatitis virus (JHMV), a murine coronavirus, results in an acute encephalomyelitis followed by viral persistence in white matter tracts accompanied by chronic neuroinflammation and demyelination. Microglia are the resident immune cell of the central nervous system (CNS) and are considered important in regulating events associated with neuroinflammation as well as influencing both white matter damage and remyelination. To better understand mechanisms by which microglia contribute to these immune-mediated events, JHMV-infected mice with established demyelination were treated with the small molecular inhibitor of colony stimulating factor 1 receptor (CSF1R), PLX5622, to deplete microglia. Treatment with PLX5622 did not affect viral replication within the CNS yet the severity of demyelination was increased and remyelination impaired compared to control mice. Gene expression analysis revealed that targeting microglia resulted in altered expression of genes associated with immune cell activation and phagocytosis of myelin debris. These findings indicate that microglia are not critical in viral surveillance in persistently JHMV-infected mice yet restrict white matter damage and remyelination, in part, by influencing phagocytosis of myelin debris.
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Affiliation(s)
- Yuting Cheng
- Department of Molecular Biology & Biochemistry, School of Biological Sciences, University of California, Irvine 92697, USA
| | - Dominic Ibarra Javonillo
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine 92697, USA
| | - Collin Pachow
- Department of Molecular Biology & Biochemistry, School of Biological Sciences, University of California, Irvine 92697, USA
| | - Vanessa M Scarfone
- Sue & Bill Gross Stem Cell Research Center, University of California, Irvine 92697, USA
| | - Kellie Fernandez
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine 92697, USA
| | - Craig M Walsh
- Department of Molecular Biology & Biochemistry, School of Biological Sciences, University of California, Irvine 92697, USA
| | - Kim N Green
- Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine 92697, USA
| | - Thomas E Lane
- Department of Molecular Biology & Biochemistry, School of Biological Sciences, University of California, Irvine 92697, USA; Department of Neurobiology & Behavior, School of Biological Sciences, University of California, Irvine 92697, USA; Center for Virus Research, University of California, Irvine 92697, USA.
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4
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Zhang X, Chen F, Sun M, Wu N, Liu B, Yi X, Ge R, Fan X. Microglia in the context of multiple sclerosis. Front Neurol 2023; 14:1157287. [PMID: 37360338 PMCID: PMC10287974 DOI: 10.3389/fneur.2023.1157287] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/10/2023] [Indexed: 06/28/2023] Open
Abstract
Multiple sclerosis (MS) is an inflammatory and neurodegenerative disease that commonly results in nontraumatic disability in young adults. The characteristic pathological hallmark of MS is damage to myelin, oligodendrocytes, and axons. Microglia provide continuous surveillance in the CNS microenvironment and initiate defensive mechanisms to protect CNS tissue. Additionally, microglia participate in neurogenesis, synaptic refinement, and myelin pruning through the expression and release of different signaling factors. Continuous activation of microglia has been implicated in neurodegenerative disorders. We first review the lifetime of microglia, including the origin, differentiation, development, and function of microglia. We then discuss microglia participate in the whole processes of remyelination and demyelination, microglial phenotypes in MS, and the NF-κB/PI3K-AKT signaling pathway in microglia. The damage to regulatory signaling pathways may change the homeostasis of microglia, which would accelerate the progression of MS.
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Affiliation(s)
- Xue Zhang
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Fang Chen
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Mingyue Sun
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Nan Wu
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Bin Liu
- Institute for Metabolic and Neuropsychiatric Disorders, Binzhou Medical University Hospital, Binzhou, China
| | - Xiangming Yi
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Ruli Ge
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Xueli Fan
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
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Hülskötter K, Lühder F, Leitzen E, Flügel A, Baumgärtner W. CD28-signaling can be partially compensated in CD28-knockout mice but is essential for virus elimination in a murine model of multiple sclerosis. Front Immunol 2023; 14:1105432. [PMID: 37090733 PMCID: PMC10113529 DOI: 10.3389/fimmu.2023.1105432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 03/20/2023] [Indexed: 04/08/2023] Open
Abstract
The intracerebral infection of mice with Theiler’s murine encephalomyelitis virus (TMEV) represents a well-established animal model for multiple sclerosis (MS). Because CD28 is the main co-stimulatory molecule for the activation of T cells, we wanted to investigate its impact on the course of the virus infection as well as on a potential development of autoimmunity as seen in susceptible mouse strains for TMEV. In the present study, 5 weeks old mice on a C57BL/6 background with conventional or tamoxifen-induced, conditional CD28-knockout were infected intracerebrally with TMEV-BeAn. In the acute phase at 14 days post TMEV-infection (dpi), both CD28-knockout strains showed virus spread within the central nervous system (CNS) as an uncommon finding in C57BL/6 mice, accompanied by histopathological changes such as reduced microglial activation. In addition, the conditional, tamoxifen-induced CD28-knockout was associated with acute clinical deterioration and weight loss, which limited the observation period for this mouse strain to 14 dpi. In the chronic phase (42 and 147 dpi) of TMEV-infection, surprisingly only 33% of conventional CD28-knockout mice showed chronic TMEV-infection with loss of motor function concomitant with increased spinal cord inflammation, characterized by T- and B cell infiltration, microglial activation and astrogliosis at 33-42 dpi. Therefore, the clinical outcome largely depends on the time point of the CD28-knockout during development of the immune system. Whereas a fatal clinical outcome can already be observed in the early phase during TMEV-infection for conditional, tamoxifen-induced CD28-knockout mice, only one third of conventional CD28-knockout mice develop clinical symptoms later, accompanied by ongoing inflammation and an inability to clear the virus. However, the development of autoimmunity could not be observed in this C57BL/6 TMEV model irrespective of the time point of CD28 deletion.
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Affiliation(s)
- Kirsten Hülskötter
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Fred Lühder
- Institute for Neuroimmunology and Multiple Sclerosis Research (IMSF), University Medical Center Goettingen, Goettingen, Germany
| | - Eva Leitzen
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Alexander Flügel
- Institute for Neuroimmunology and Multiple Sclerosis Research (IMSF), University Medical Center Goettingen, Goettingen, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
- *Correspondence: Wolfgang Baumgärtner,
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Spiteri AG, Wishart CL, Ni D, Viengkhou B, Macia L, Hofer MJ, King NJC. Temporal tracking of microglial and monocyte single-cell transcriptomics in lethal flavivirus infection. Acta Neuropathol Commun 2023; 11:60. [PMID: 37016414 PMCID: PMC10074823 DOI: 10.1186/s40478-023-01547-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 03/08/2023] [Indexed: 04/06/2023] Open
Abstract
As the resident parenchymal myeloid population in the central nervous system (CNS), microglia are strategically positioned to respond to neurotropic virus invasion and have been implicated in promoting both disease resolution and progression in the acute and post-infectious phase of virus encephalitis. In a mouse model of West Nile virus encephalitis (WNE), infection of the CNS results in recruitment of large numbers of peripheral immune cells into the brain, the majority being nitric oxide (NO)-producing Ly6Chi inflammatory monocyte-derived cells (MCs). In this model, these cells enhance immunopathology and mortality. However, the contribution of microglia to this response is currently undefined. Here we used a combination of experimental tools, including single-cell RNA sequencing (scRNA-seq), microglia and MC depletion reagents, high-dimensional spectral cytometry and computational algorithms to dissect the differential contribution of microglia and MCs to the anti-viral immune response in severe neuroinflammation seen in WNE. Intriguingly, analysis of scRNA-seq data revealed 6 unique microglia and 3 unique MC clusters that were predominantly timepoint-specific, demonstrating substantial transcriptional adaptation with disease progression over the course of WNE. While microglia and MC adopted unique gene expression profiles, gene ontology enrichment analysis, coupled with microglia and MC depletion studies, demonstrated a role for both of these cells in the trafficking of peripheral immune cells into the CNS, T cell responses and viral clearance. Over the course of infection, microglia transitioned from a homeostatic to an anti-viral and then into an immune cell-recruiting phenotype. Conversely, MC adopted antigen-presenting, immune cell-recruiting and NO-producing phenotypes, which all had anti-viral function. Overall, this study defines for the first time the single-cell transcriptomic responses of microglia and MCs over the course of WNE, demonstrating both protective and pathological roles of these cells that could potentially be targeted for differential therapeutic intervention to dampen immune-mediated pathology, while maintaining viral clearance functions.
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Affiliation(s)
- Alanna G Spiteri
- Viral Immunopathology Laboratory, Infection, Immunity and Inflammation Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, 2006, Australia
- Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, 2006, Australia
- Ramaciotti Facility for Human Systems Biology, The University of Sydney and Centenary Institute, Sydney, NSW, 2006, Australia
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Claire L Wishart
- Viral Immunopathology Laboratory, Infection, Immunity and Inflammation Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, 2006, Australia
- Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, 2006, Australia
- Ramaciotti Facility for Human Systems Biology, The University of Sydney and Centenary Institute, Sydney, NSW, 2006, Australia
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Duan Ni
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
- Chronic Diseases Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Barney Viengkhou
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Laurence Macia
- Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, 2006, Australia
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
- Chronic Diseases Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Markus J Hofer
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
- The University of Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Nicholas J C King
- Viral Immunopathology Laboratory, Infection, Immunity and Inflammation Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, 2006, Australia.
- Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, 2006, Australia.
- Ramaciotti Facility for Human Systems Biology, The University of Sydney and Centenary Institute, Sydney, NSW, 2006, Australia.
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, 2006, Australia.
- The University of Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, NSW, 2006, Australia.
- Sydney Nano, The University of Sydney, Sydney, NSW, 2006, Australia.
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Johnson HJ, Koshy AA. Understanding neuroinflammation through central nervous system infections. Curr Opin Neurobiol 2022; 76:102619. [PMID: 35985075 PMCID: PMC10147316 DOI: 10.1016/j.conb.2022.102619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/09/2022] [Accepted: 07/08/2022] [Indexed: 11/28/2022]
Abstract
Neuroinflammation is now recognized to compound many central nervous system (CNS) pathologies, from stroke to dementia. As immune responses evolved to handle infections, studying CNS infections can offer unique insights into the CNS immune response and address questions such as: What defenses and strategies do CNS parenchymal cells deploy in response to a dangerous pathogen? How do CNS cells interact with each other and infiltrating immune cells to control microbes? What pathways are beneficial for the host or for the pathogen? Here, we review recent studies that use CNS-tropic infections in combination with cutting-edge techniques to delve into the complex relationships between microbes, immune cells, and cells of the CNS.
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Affiliation(s)
- Hannah J Johnson
- Neuroscience Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA
| | - Anita A Koshy
- Neuroscience Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA; Department of Neurology, University of Arizona, Tucson, AZ, USA; BIO5 Institute, University of Arizona, Tucson, AZ, USA; Department of Immunobiology, University of Arizona, Tucson, AZ, USA.
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Spiteri AG, Ni D, Ling ZL, Macia L, Campbell IL, Hofer MJ, King NJC. PLX5622 Reduces Disease Severity in Lethal CNS Infection by Off-Target Inhibition of Peripheral Inflammatory Monocyte Production. Front Immunol 2022; 13:851556. [PMID: 35401512 PMCID: PMC8990748 DOI: 10.3389/fimmu.2022.851556] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 03/03/2022] [Indexed: 11/18/2022] Open
Abstract
PLX5622 is a CSF-1R inhibitor and microglia-depleting reagent, widely used to investigate the biology of this central nervous system (CNS)-resident myeloid population, but the indirect or off-target effects of this agent remain largely unexplored. In a murine model of severe neuroinflammation induced by West Nile virus encephalitis (WNE), we showed PLX5622 efficiently depleted both microglia and a sub-population of border-associated macrophages in the CNS. However, PLX5622 also significantly depleted mature Ly6Chi monocytes in the bone marrow (BM), inhibiting their proliferation and lethal recruitment into the infected brain, reducing neuroinflammation and clinical disease scores. Notably, in addition, BM dendritic cell subsets, plasmacytoid DC and classical DC, were depleted differentially in infected and uninfected mice. Confirming its protective effect in WNE, cessation of PLX5622 treatment exacerbated disease scores and was associated with robust repopulation of microglia, rebound BM monopoiesis and markedly increased inflammatory monocyte infiltration into the CNS. Monoclonal anti-CSF-1R antibody blockade late in WNE also impeded BM monocyte proliferation and recruitment to the brain, suggesting that the protective effect of PLX5622 is via the inhibition of CSF-1R, rather than other kinase targets. Importantly, BrdU incorporation in PLX5622-treated mice, suggest remaining microglia proliferate independently of CSF-1 in WNE. Our study uncovers significantly broader effects of PLX5622 on the myeloid lineage beyond microglia depletion, advising caution in the interpretation of PLX5622 data as microglia-specific. However, this work also strikingly demonstrates the unexpected therapeutic potential of this molecule in CNS viral infection, as well as other monocyte-mediated diseases.
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Affiliation(s)
- Alanna G Spiteri
- Viral Immunopathology Laboratory, Infection, Immunity and Inflammation Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Ramaciotti Facility for Human Systems Biology, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
| | - Duan Ni
- Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia.,Chronic Diseases Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Zheng Lung Ling
- Viral Immunopathology Laboratory, Infection, Immunity and Inflammation Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Ramaciotti Facility for Human Systems Biology, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia
| | - Laurence Macia
- Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Ramaciotti Facility for Human Systems Biology, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia.,Chronic Diseases Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Iain L Campbell
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Markus J Hofer
- Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia.,School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia.,The University of Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, NSW, Australia
| | - Nicholas J C King
- Viral Immunopathology Laboratory, Infection, Immunity and Inflammation Research Theme, School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Sydney Cytometry, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Ramaciotti Facility for Human Systems Biology, The University of Sydney and Centenary Institute, Sydney, NSW, Australia.,Charles Perkins Centre, The University of Sydney, Sydney, NSW, Australia.,The University of Sydney Institute for Infectious Diseases, The University of Sydney, Sydney, NSW, Australia.,The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW, Australia
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Tsai MS, Wang LC, Tsai HY, Lin YJ, Wu HL, Tzeng SF, Hsu SM, Chen SH. Microglia Reduce Herpes Simplex Virus 1 Lethality of Mice with Decreased T Cell and Interferon Responses in Brains. Int J Mol Sci 2021; 22:ijms222212457. [PMID: 34830340 PMCID: PMC8624831 DOI: 10.3390/ijms222212457] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/09/2021] [Accepted: 11/16/2021] [Indexed: 12/11/2022] Open
Abstract
Herpes simplex virus 1 (HSV-1) infects the majority of the human population and can induce encephalitis, which is the most common cause of sporadic, fatal encephalitis. An increase of microglia is detected in the brains of encephalitis patients. The issues regarding whether and how microglia protect the host and neurons from HSV-1 infection remain elusive. Using a murine infection model, we showed that HSV-1 infection on corneas increased the number of microglia to outnumber those of infiltrating leukocytes (macrophages, neutrophils, and T cells) and enhanced microglia activation in brains. HSV-1 antigens were detected in brain neurons, which were surrounded by microglia. Microglia depletion increased HSV-1 lethality of mice with elevated brain levels of viral loads, infected neurons, neuron loss, CD4 T cells, CD8 T cells, neutrophils, interferon (IFN)-β, and IFN-γ. In vitro studies demonstrated that microglia from infected mice reduced virus infectivity. Moreover, microglia induced IFN-β and the signaling pathway of signal transducer and activator of transcription (STAT) 1 to inhibit viral replication and damage of neurons. Our study reveals how microglia protect the host and neurons from HSV-1 infection.
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Affiliation(s)
- Meng-Shan Tsai
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan; (M.-S.T.); (H.-L.W.)
| | - Li-Chiu Wang
- School of Medicine, I-Shou University, Kaohsiung 824, Taiwan;
| | - Hsien-Yang Tsai
- Department of Ophthalmology, Tzu Chi Hospital, Taichung 427, Taiwan;
| | - Yu-Jheng Lin
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan;
| | - Hua-Lin Wu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan; (M.-S.T.); (H.-L.W.)
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
| | - Shun-Fen Tzeng
- Department of Life Sciences, College of Biological Science and Biotechnology, National Cheng Kung University, Tainan 701, Taiwan;
| | - Sheng-Min Hsu
- Department of Ophthalmology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan
- Correspondence: (S.-M.H.); (S.-H.C.)
| | - Shun-Hua Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan; (M.-S.T.); (H.-L.W.)
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan 701, Taiwan;
- Correspondence: (S.-M.H.); (S.-H.C.)
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