1
|
Hay A, Popichak K, Moreno J, Zabel M. The Role of Glial Cells in Neurobiology and Prion Neuropathology. Cells 2024; 13:832. [PMID: 38786054 PMCID: PMC11119027 DOI: 10.3390/cells13100832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024] Open
Abstract
Prion diseases are rare and neurodegenerative diseases that are characterized by the misfolding and infectious spread of the prion protein in the brain, causing progressive and irreversible neuronal loss and associated clinical and behavioral manifestations in humans and animals, ultimately leading to death. The brain has a complex network of neurons and glial cells whose crosstalk is critical for function and homeostasis. Although it is established that prion infection of neurons is necessary for clinical disease to occur, debate remains in the field as to the role played by glial cells, namely astrocytes and microglia, and whether these cells are beneficial to the host or further accelerate disease. Here, we review the current literature assessing the complex morphologies of astrocytes and microglia, and the crosstalk between these two cell types, in the prion-infected brain.
Collapse
Affiliation(s)
- Arielle Hay
- Division of Intramural Research, Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840, USA
| | - Katriana Popichak
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (K.P.); (J.M.); (M.Z.)
| | - Julie Moreno
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (K.P.); (J.M.); (M.Z.)
- Department of Environmental and Radiological Health Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Mark Zabel
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (K.P.); (J.M.); (M.Z.)
| |
Collapse
|
2
|
Kang SG, Kim C, Aiken J, McKenzie D. Innate Immune Status of Glia Modulates Prion Propagation in Early Stage of Infection. Cells 2023; 12:1878. [PMID: 37508542 PMCID: PMC10378504 DOI: 10.3390/cells12141878] [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: 06/22/2023] [Revised: 07/11/2023] [Accepted: 07/11/2023] [Indexed: 07/30/2023] Open
Abstract
Prion diseases are progressive neurodegenerative disorders affecting humans and various mammals. The prominent neuropathological change in prion-affected brains is neuroinflammation, histopathologically characterized by reactive gliosis surrounding prion deposition. The cause and effect of these cellular responses are still unclear. Here we investigate the impact of innate immune responses on prion replication using in vitro cell culture models. Hamster-adapted transmissible mink encephalopathy prions, hyper (HY) and drowsy (DY) strains, were assayed for accumulation of pathogenic prion protein (PrPSc) in primary glial cultures derived from 8-day-old hamster pups. The kinetics of PrPSc accumulation largely depended on prion strain and brain regions from where glial cells originated. Glial cells derived from the cerebellum were susceptible to HY, but resistant to DY strain as determined by western blot analysis, immunocytochemistry, and animal bioassay. Glial cells from the cerebral cortex were, however, refractory to both strains. PrPSc accumulation was affected by innate immune modulators. Priming glial cells with lipopolysaccharide decreased prion replication, whereas pre-treatment with dexamethasone, inhibiting innate immunity, increased susceptibility to DY infection. Our results suggest that neuroinflammation resulting from prion infection is a response to resolve and/or prevent prion propagation in the brain. It implies a therapeutic potential of innate immune modulation in the early stages of prion disease.
Collapse
Affiliation(s)
- Sang-Gyun Kang
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
- Department of Medicine, University of Alberta, Edmonton, AB T6G 2R7, Canada
| | - Chiye Kim
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| | - Judd Aiken
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
- Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 1C9, Canada
| | - Debbie McKenzie
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB T6G 2M8, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada
| |
Collapse
|
3
|
Troshev D, Blokhin V, Ukrainskaya V, Kolacheva A, Ugrumov M. Isolation of living dopaminergic neurons labeled with a fluorescent ligand of the dopamine transporter from mouse substantia nigra as a new tool for basic and applied research. Front Mol Neurosci 2022; 15:1020070. [PMID: 36568278 PMCID: PMC9780273 DOI: 10.3389/fnmol.2022.1020070] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 11/21/2022] [Indexed: 12/13/2022] Open
Abstract
Dopaminergic neurons (DNs) of the nigrostriatal system control the motor function, and their degeneration leads to the development of Parkinson's disease (PD). A stumbling block in the study of DNs in the whole substantia nigra (SN) is the lack of tools to analyze the expression of most of the genes involved in neurotransmission, neurodegeneration, and neuroplasticity, since they are also expressed in other cells of the SN. Therefore, this study aimed to develop a fluorescence-activated cell sorting method for isolating living DNs from the SN of wild-type mice using two fluorescent dyes, DRAQ5 (nuclear stain) and a dopamine uptake inhibitor GBR 12909 coupled to a fluorophore (DN stain). We have developed a method for selecting a population of DNs from the SN of mice, as evidenced by: (i) immunopositivity of 95% of the sorted cells for tyrosine hydroxylase, the first enzyme of dopamine synthesis; (ii) the sorted cells expressing the genes for specific proteins of the dopaminergic phenotype, tyrosine hydroxylase, the dopamine transporter, and vesicular monoamine transporter 2 and non-specific proteins, such as aromatic L-amino acid decarboxylase, non-specific enzyme of dopamine synthesis. We then compared the changes in gene expression found in the sorted DNs and in the SN homogenate in a PD model we developed, reproduced in mice by treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Using quantitative PCR, we obtained evidence of the same changes in the expression of specific genes in the sorted DNs of SN and in the SN homogenate of a MPTP mouse model of PD, compared with the control. The undoubted advantage of our approach is the possibility of obtaining a large amount of readily available and relatively cheap primary material (SN) from wild-type mice, which can be used to solve both research and applied problems. In addition, this method can be easily adapted to the isolation of DNs from the SN in other animal species, including non-human primates.
Collapse
Affiliation(s)
- Dmitry Troshev
- Laboratory of Neural and Neuroendocrine Regulations, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
| | - Victor Blokhin
- Laboratory of Neural and Neuroendocrine Regulations, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
| | - Valeria Ukrainskaya
- Laboratory of Biocatalysis, Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Anna Kolacheva
- Laboratory of Neural and Neuroendocrine Regulations, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia
| | - Michael Ugrumov
- Laboratory of Neural and Neuroendocrine Regulations, Koltzov Institute of Developmental Biology of the Russian Academy of Sciences, Moscow, Russia,*Correspondence: Michael Ugrumov,
| |
Collapse
|
4
|
Hussain H, Djurin T, Rodriguez J, Daneelian L, Sundi S, Fadel A, Saadoon Z. Transactivation Response DNA-Binding Protein of 43 (TDP-43) and Glial Cell Roles in Neurological Disorders. Cureus 2022; 14:e30639. [DOI: 10.7759/cureus.30639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2022] [Indexed: 11/07/2022] Open
|
5
|
Smethurst P, Franklin H, Clarke BE, Sidle K, Patani R. The role of astrocytes in prion-like mechanisms of neurodegeneration. Brain 2022; 145:17-26. [PMID: 35265969 PMCID: PMC8967097 DOI: 10.1093/brain/awab366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 08/20/2021] [Accepted: 09/03/2021] [Indexed: 11/13/2022] Open
Abstract
Accumulating evidence suggests that neurodegenerative diseases are not merely neuronal in nature but comprise multicellular involvement, with astrocytes emerging as key players. The pathomechanisms of several neurodegenerative diseases involve the deposition of misfolded protein aggregates in neurons that have characteristic prion-like behaviours such as template-directed seeding, intercellular propagation, distinct conformational strains and protein-mediated toxicity. The role of astrocytes in dealing with these pathological prion-like protein aggregates and whether their responses either protect from or conspire with the disease process is currently unclear. Here we review the existing literature implicating astrocytes in multiple neurodegenerative proteinopathies with a focus on prion-like behaviour in this context.
Collapse
Affiliation(s)
- Phillip Smethurst
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Hannah Franklin
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Benjamin E Clarke
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Katie Sidle
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
- Correspondence may also be addressed to: Katie Sidle E-mail:
| | - Rickie Patani
- Department of Neuromuscular Disease, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
- Correspondence to: Rickie Patani The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK E-mail:
| |
Collapse
|
6
|
Owyong TC, Hong Y. Emerging fluorescence tools for the study of proteostasis in cells. Curr Opin Chem Biol 2022; 67:102116. [PMID: 35176555 DOI: 10.1016/j.cbpa.2022.102116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/22/2021] [Accepted: 01/12/2022] [Indexed: 11/25/2022]
Abstract
Understanding how cells maintain the functional proteome and respond to stress conditions is critical for deciphering molecular pathogenesis and developing treatments for conditions such as neurodegenerative diseases. Efforts towards finer quantification of cellular proteostasis machinery efficiency, phase transitions and local environment changes remain a priority. Herein, we describe recent developments in fluorescence-based strategy and methodology, building on the experimental toolkit, for the study of proteostasis (protein homeostasis) in cells. We hope this review can assist in bridging gaps between a multitude of research disciplines and promote interdisciplinary collaboration to address the crucial topic of proteostasis.
Collapse
Affiliation(s)
- Tze Cin Owyong
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, 3086, Australia; ARC Centre of Excellence in Exciton Science, School of Chemistry, Bio21 Institute, The University of Melbourne, Victoria, 3010, Australia
| | - Yuning Hong
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, 3086, Australia.
| |
Collapse
|
7
|
Sinha A, Kushwaha R, Molesworth K, Mychko O, Makarava N, Baskakov IV. Phagocytic Activities of Reactive Microglia and Astrocytes Associated with Prion Diseases Are Dysregulated in Opposite Directions. Cells 2021; 10:1728. [PMID: 34359897 PMCID: PMC8304827 DOI: 10.3390/cells10071728] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/02/2021] [Accepted: 07/04/2021] [Indexed: 01/11/2023] Open
Abstract
Phagocytosis is one of the most important physiological functions of the glia directed at maintaining a healthy, homeostatic environment in the brain. Under a homeostatic environment, the phagocytic activities of astrocytes and microglia are tightly coordinated in time and space. In neurodegenerative diseases, both microglia and astrocytes contribute to neuroinflammation and disease pathogenesis, however, whether their phagocytic activities are up- or downregulated in reactive states is not known. To address this question, this current study isolated microglia and astrocytes from C57BL/6J mice infected with prions and tested their phagocytic activities in live-cell imaging assays that used synaptosomes and myelin debris as substrates. The phagocytic uptake by the reactive microglia was found to be significantly upregulated, whereas that of the reactive astrocytes was strongly downregulated. The up- and downregulation of phagocytosis by the two cell types were observed irrespective of whether disease-associated synaptosomes, normal synaptosomes, or myelin debris were used in the assays, indicating that dysregulations are dictated by cell reactive states, not substrates. Analysis of gene expression confirmed dysregulation of phagocytic functions in both cell types. Immunostaining of animal brains infected with prions revealed that at the terminal stage of disease, neuronal cell bodies were subject to engulfment by reactive microglia. This study suggests that imbalance in the phagocytic activities of the reactive microglia and astrocytes, which are dysregulated in opposite directions, is likely to lead to excessive microglia-mediated neuronal death on the one hand, and the inability of astrocytes to clear cell debris on the other hand, contributing to the neurotoxic effects of glia as a whole.
Collapse
Affiliation(s)
- Anshuman Sinha
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.S.); (R.K.); (K.M.); (O.M.); (N.M.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Rajesh Kushwaha
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.S.); (R.K.); (K.M.); (O.M.); (N.M.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Kara Molesworth
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.S.); (R.K.); (K.M.); (O.M.); (N.M.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Olga Mychko
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.S.); (R.K.); (K.M.); (O.M.); (N.M.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Natallia Makarava
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.S.); (R.K.); (K.M.); (O.M.); (N.M.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Ilia V. Baskakov
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (A.S.); (R.K.); (K.M.); (O.M.); (N.M.)
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| |
Collapse
|
8
|
Microglial Turnover in Ageing-Related Neurodegeneration: Therapeutic Avenue to Intervene in Disease Progression. Cells 2021; 10:cells10010150. [PMID: 33466587 PMCID: PMC7828713 DOI: 10.3390/cells10010150] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/11/2021] [Accepted: 01/11/2021] [Indexed: 02/06/2023] Open
Abstract
Microglia are brain-dwelling macrophages and major parts of the neuroimmune system that broadly contribute to brain development, homeostasis, ageing and injury repair in the central nervous system (CNS). Apart from other brain macrophages, they have the ability to constantly sense changes in the brain’s microenvironment, functioning as housekeepers for neuronal well-being and providing neuroprotection in normal physiology. Microglia use a set of genes for these functions that involve proinflammatory cytokines. In response to specific stimuli, they release these proinflammatory cytokines, which can damage and kill neurons via neuroinflammation. However, alterations in microglial functioning are a common pathophysiology in age-related neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, Huntington’s and prion diseases, as well as amyotrophic lateral sclerosis, frontotemporal dementia and chronic traumatic encephalopathy. When their sentinel or housekeeping functions are severely disrupted, they aggravate neuropathological conditions by overstimulating their defensive function and through neuroinflammation. Several pathways are involved in microglial functioning, including the Trem2, Cx3cr1 and progranulin pathways, which keep the microglial inflammatory response under control and promote clearance of injurious stimuli. Over time, an imbalance in this system leads to protective microglia becoming detrimental, initiating or exacerbating neurodegeneration. Correcting such imbalances might be a potential mode of therapeutic intervention in neurodegenerative diseases.
Collapse
|
9
|
Ritzel RM, Li Y, He J, Khan N, Doran SJ, Faden AI, Wu J. Sustained neuronal and microglial alterations are associated with diverse neurobehavioral dysfunction long after experimental brain injury. Neurobiol Dis 2019; 136:104713. [PMID: 31843705 PMCID: PMC7155942 DOI: 10.1016/j.nbd.2019.104713] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 11/17/2019] [Accepted: 12/12/2019] [Indexed: 12/12/2022] Open
Abstract
Traumatic brain injury (TBI) can cause progressive neurodegeneration, sustained neuroinflammation and chronic neurological dysfunction. Few experimental studies have explored the long-term neurobehavioral and functional cellular changes beyond several months. The present study examined the effects of a single moderate-level TBI on functional outcome 8 months after injury. Male C57BL/6 mice were subjected to controlled cortical impact injury and followed for changes in motor performance, learning and memory, as well as depressive-like and social behavior. We also used a novel flow cytometry approach to assess cellular functions in freshly isolated neurons and microglia from the injured tissue. There were marked and diverse, sustained neurobehavioral changes in injured mice. Compared to sham controls, chronic TBI mice showed long-term deficits in gait dynamics, nest building, spatial working memory and recognition memory. The tail suspension, forced swim, and sucrose consumption tests showed a marked depressive-like phenotype that was associated with impaired sociability. At the cellular level, there were lower numbers of Thy1+Tuj1+ neurons and higher numbers of activated CD45loCD11b+ microglia. Functionally, both neurons and microglia exhibited significantly higher levels of oxidative stress after injury. Microglia exhibited chronic deficits in phagocytosis of E. coli bacteria, and increased uptake of myelin and dying neurons. Living neurons showed decreased expression of synaptophysin and postsynaptic density (PSD)-95, along with greater numbers of microtubule-associated protein light chain 3 (LC3)-positive autophagosomes and increased mitochondrial mass that suggest dysregulation of autophagy. In summary, the late neurobehavioral changes found after murine TBI are similar to those found chronically after moderate-severe human head injury. Importantly, such changes are associated with microglial dysfunction and changes in neuronal activity.
Collapse
Affiliation(s)
- Rodney M Ritzel
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland, School of Medicine, Baltimore, MD 21201, USA
| | - Yun Li
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland, School of Medicine, Baltimore, MD 21201, USA
| | - Junyun He
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland, School of Medicine, Baltimore, MD 21201, USA
| | - Niaz Khan
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland, School of Medicine, Baltimore, MD 21201, USA
| | - Sarah J Doran
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland, School of Medicine, Baltimore, MD 21201, USA
| | - Alan I Faden
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland, School of Medicine, Baltimore, MD 21201, USA; University of Maryland, Center to Advance Chronic Pain Research, University of Maryland, Baltimore, MD 21201, USA
| | - Junfang Wu
- Department of Anesthesiology and Center for Shock, Trauma and Anesthesiology Research (STAR), University of Maryland, School of Medicine, Baltimore, MD 21201, USA; University of Maryland, Center to Advance Chronic Pain Research, University of Maryland, Baltimore, MD 21201, USA.
| |
Collapse
|
10
|
Suzuki A, Yamasaki T, Hasebe R, Horiuchi M. Enhancement of binding avidity by bivalent binding enables PrPSc-specific detection by anti-PrP monoclonal antibody 132. PLoS One 2019; 14:e0217944. [PMID: 31170247 PMCID: PMC6553756 DOI: 10.1371/journal.pone.0217944] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 05/21/2019] [Indexed: 12/05/2022] Open
Abstract
Anti-prion protein (PrP) monoclonal antibody 132, which recognizes mouse PrP amino acids 119–127, enables us to reliably detect abnormal isoform prion protein (PrPSc) in cells or frozen tissue sections by immunofluorescence assay, although treatment with guanidinium salts is a prerequisite. Despite the benefit of this mAb, the mechanism of PrPSc-specific detection remains unclear. Therefore, to address this mechanism, we analyzed the reactivities of mono- and bivalent mAb 132 to recombinant mouse PrP (rMoPrP) by enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR). In ELISA, binding of the monovalent form was significantly weaker than that of the bivalent form, indicating that bivalent binding confers a higher binding stability to mAb 132. Compared with other anti-PrP mAbs tested, the reactivity of bivalent mAb 132 was easily affected by a decrease in antigen concentration. The binding kinetics of mAb 132 assessed by SPR were consistent with the results of ELISA. The dissociation constant of the monovalent form was approximately 260 times higher than that of the bivalent form, suggesting that monovalent binding is less stable than bivalent binding. Furthermore, the amount of mAb 132 that bound to rMoPrP decreased if the antigen density was too low to allow bivalent binding. If two cellular PrP (PrPC) are close enough to allow bivalent binding, mAb 132 binds to PrPC. These results indicate that weak monovalent binding to monomeric PrPC diminishes PrPC signals to background level, whereas after exposure of the epitope, mAb 132 binds stably to oligomeric PrPSc in a bivalent manner.
Collapse
Affiliation(s)
- Akio Suzuki
- Laboratory of Veterinary Hygiene, Faculty of Veterinary Medicine, Graduate School of Infectious Diseases, Hokkaido University, Kita-ku, Sapporo, Japan
| | - Takeshi Yamasaki
- Laboratory of Veterinary Hygiene, Faculty of Veterinary Medicine, Graduate School of Infectious Diseases, Hokkaido University, Kita-ku, Sapporo, Japan
| | - Rie Hasebe
- Biomedical Animal Research Laboratory, Institute for Genetic Medicine, Hokkaido University, Kita-ku, Sapporo, Japan
| | - Motohiro Horiuchi
- Laboratory of Veterinary Hygiene, Faculty of Veterinary Medicine, Graduate School of Infectious Diseases, Hokkaido University, Kita-ku, Sapporo, Japan
- Global Station for Zoonosis Control. Global Institute for Collaborative Research and Education, Hokkaido University, Kita-ku, Sapporo, Japan
- * E-mail:
| |
Collapse
|
11
|
Hartmann K, Sepulveda-Falla D, Rose IVL, Madore C, Muth C, Matschke J, Butovsky O, Liddelow S, Glatzel M, Krasemann S. Complement 3 +-astrocytes are highly abundant in prion diseases, but their abolishment led to an accelerated disease course and early dysregulation of microglia. Acta Neuropathol Commun 2019; 7:83. [PMID: 31118110 PMCID: PMC6530067 DOI: 10.1186/s40478-019-0735-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 05/13/2019] [Indexed: 01/01/2023] Open
Abstract
Astrogliosis and activation of microglia are hallmarks of prion diseases in humans and animals. Both were viewed to be rather independent events in disease pathophysiology, with proinflammatory microglia considered to be the potential neurotoxic species at late disease stages. Recent investigations have provided substantial evidence that a proinflammatory microglial cytokine cocktail containing TNF-α, IL-1α and C1qa reprograms a subset of astrocytes to change their expression profile and phenotype, thus becoming neurotoxic (designated as A1-astrocytes). Knockout or antibody blockage of the three cytokines abolish formation of A1-astrocytes, therefore, this pathway is of high therapeutic interest in neurodegenerative diseases. Since astrocyte polarization profiles have never been investigated in prion diseases, we performed several analyses and could show that C3+-PrPSc-reactive-astrocytes, which may represent a subtype of A1-astrocytes, are highly abundant in prion disease mouse models and human prion diseases. To investigate their impact on prion disease pathophysiology and to evaluate their potential therapeutic targeting, we infected TNF-α, IL-1α, and C1qa Triple-KO mice (TKO-mice), which do not transit astrocytes into A1, with prions. Although formation of C3+-astrocytes was significantly reduced in prion infected Triple-KO-mice, this did not affect the amount of PrPSc deposition or titers of infectious prions. Detailed characterization of the astrocyte activation signature in thalamus tissue showed that astrocytes in prion diseases are highly activated, showing a mixed phenotype that is distinct from other neurodegenerative diseases and were therefore termed C3+-PrPSc-reactive-astrocytes. Unexpectedly, Triple-KO led to a significant acceleration of prion disease course. While pan-astrocyte and -microglia marker upregulation was unchanged compared to WT-brains, microglial homeostatic markers were lost early in disease in TKO-mice, pointing towards important functions of different glia cell types in prion diseases.
Collapse
|
12
|
Hickman S, Izzy S, Sen P, Morsett L, El Khoury J. Microglia in neurodegeneration. Nat Neurosci 2018; 21:1359-1369. [PMID: 30258234 DOI: 10.1038/s41593-018-0242-x] [Citation(s) in RCA: 947] [Impact Index Per Article: 157.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 08/06/2018] [Indexed: 12/13/2022]
Abstract
The neuroimmune system is involved in development, normal functioning, aging, and injury of the central nervous system. Microglia, first described a century ago, are the main neuroimmune cells and have three essential functions: a sentinel function involved in constant sensing of changes in their environment, a housekeeping function that promotes neuronal well-being and normal operation, and a defense function necessary for responding to such changes and providing neuroprotection. Microglia use a defined armamentarium of genes to perform these tasks. In response to specific stimuli, or with neuroinflammation, microglia also have the capacity to damage and kill neurons. Injury to neurons in Alzheimer's, Parkinson's, Huntington's, and prion diseases, as well as in amyotrophic lateral sclerosis, frontotemporal dementia, and chronic traumatic encephalopathy, results from disruption of the sentinel or housekeeping functions and dysregulation of the defense function and neuroinflammation. Pathways associated with such injury include several sensing and housekeeping pathways, such as the Trem2, Cx3cr1 and progranulin pathways, which act as immune checkpoints to keep the microglial inflammatory response under control, and the scavenger receptor pathways, which promote clearance of injurious stimuli. Peripheral interference from systemic inflammation or the gut microbiome can also alter progression of such injury. Initiation or exacerbation of neurodegeneration results from an imbalance between these microglial functions; correcting such imbalance may be a potential mode for therapy.
Collapse
Affiliation(s)
- Suzanne Hickman
- Center for Immunology & Inflammatory Diseases, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Saef Izzy
- Center for Immunology & Inflammatory Diseases, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Pritha Sen
- Center for Immunology & Inflammatory Diseases, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Liza Morsett
- Center for Immunology & Inflammatory Diseases, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA
| | - Joseph El Khoury
- Center for Immunology & Inflammatory Diseases, Massachusetts General Hospital, and Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
13
|
Retrograde Transport by Clathrin-Coated Vesicles is Involved in Intracellular Transport of PrP Sc in Persistently Prion-Infected Cells. Sci Rep 2018; 8:12241. [PMID: 30115966 PMCID: PMC6095914 DOI: 10.1038/s41598-018-30775-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 08/03/2018] [Indexed: 12/22/2022] Open
Abstract
Intracellular dynamics of an abnormal isoform of prion protein (PrPSc) are tightly associated with prion propagation. However, the machineries involved in the intracellular trafficking of PrPSc are not fully understood. Our previous study suggested that PrPSc in persistently prion-infected cells dynamically circulates between endocytic-recycling compartments (ERCs) and peripheral regions of the cells. To investigate these machineries, we focused on retrograde transport from endosomes to the trans-Golgi network, which is one of the pathways involved in recycling of molecules. PrPSc was co-localized with components of clathrin-coated vesicles (CCVs) as well as those of the retromer complex, which are known as machineries for retrograde transport. Fractionation of intracellular compartments by density gradient centrifugation showed the presence of PrPSc and the components of CCVs in the same fractions. Furthermore, PrPSc was detected in CCVs isolated from intracellular compartments of prion-infected cells. Knockdown of clathrin interactor 1, which is one of the clathrin adaptor proteins involved in retrograde transport, did not change the amount of PrPSc, but it altered the distribution of PrPSc from ERCs to peripheral regions, including late endosomes/lysosomes. These data demonstrated that some PrPSc is transported from endosomes to ERCs by CCVs, which might be involved in the recycling of PrPSc.
Collapse
|
14
|
Flow cytometry for receptor analysis from ex-vivo brain tissue in adult rat. J Neurosci Methods 2018; 304:11-23. [DOI: 10.1016/j.jneumeth.2018.04.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/05/2018] [Accepted: 04/11/2018] [Indexed: 11/18/2022]
|