1
|
Pocock J, Vasilopoulou F, Svensson E, Cosker K. Microglia and TREM2. Neuropharmacology 2024; 257:110020. [PMID: 38821351 DOI: 10.1016/j.neuropharm.2024.110020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/20/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
TREM2 is a membrane receptor solely expressed on microglia in normal brain. In this review we outline recent advances in TREM2 biology and its implications for microglial function, with particular emphasis on findings from iPSC-derived microglia (iMG) expressing TREM2 loss-of-function mutations. Alterations in receptor proximal and distal signalling underlie TREM2 risk variants linked to neurodegenerative disease, principally NH-linked FTD, and late-onset AD, but emerging data suggest roles for TREM2 in PD, MS and ALS. TREM2 downstream functions include phagocytosis of myelin debris, amyloid beta peptides, and phosphatidylserine-expressing cells (resulting from damage or stress). Microglial survival, migration, DAMP signalling, inflammasome activation, and intercellular signalling including tau spreading via exosomes, as well as roles for sTREM2 in protection and as a biomarker are discussed. The role of TREM2 in metabolic homeostasis, and immunometabolic switching are discussed regarding microglial responses to damage and protection. The use of iPSC models to investigate the role of TREM2 in AD, PD, MS, ALS, and other neurodegenerative diseases could prove invaluable due to their ability to recapitulate human pathology, allowing a full understanding of TREM2 and microglial involvement in the underlying disease mechanisms and progression.
Collapse
Affiliation(s)
- Jennifer Pocock
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK.
| | - Foteini Vasilopoulou
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK
| | - Elina Svensson
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK
| | - Katharina Cosker
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK
| |
Collapse
|
2
|
Shi Q, Gutierrez RA, Bhat MA. Microglia, Trem2, and Neurodegeneration. Neuroscientist 2024:10738584241254118. [PMID: 38769824 DOI: 10.1177/10738584241254118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Microglia are a specialized type of neuroimmune cells that undergo morphological and molecular changes through multiple signaling pathways in response to pathological protein aggregates, neuronal death, tissue injury, or infections. Microglia express Trem2, which serves as a receptor for a multitude of ligands enhancing their phagocytic activity. Trem2 has emerged as a critical modulator of microglial activity, especially in many neurodegenerative disorders. Human TREM2 mutations are associated with an increased risk of developing Alzheimer disease (AD) and other neurodegenerative diseases. Trem2 plays dual roles in neuroinflammation and more specifically in disease-associated microglia. Most recent developments on the molecular mechanisms of Trem2, emphasizing its role in uptake and clearance of amyloid β (Aβ) aggregates and other tissue debris to help protect and preserve the brain, are encouraging. Although Trem2 normally stimulates defense mechanisms, its dysregulation can intensify inflammation, which poses major therapeutic challenges. Recent therapeutic approaches targeting Trem2 via agonistic antibodies and gene therapy methodologies present possible avenues for reducing the burden of neurodegenerative diseases. This review highlights the promise of Trem2 as a therapeutic target, especially for Aβ-associated AD, and calls for more mechanistic investigations to understand the context-specific role of microglial Trem2 in developing effective therapies against neurodegenerative diseases.
Collapse
Affiliation(s)
- Qian Shi
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
| | - Raul A Gutierrez
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
| |
Collapse
|
3
|
Yu Y, Chen R, Mao K, Deng M, Li Z. The Role of Glial Cells in Synaptic Dysfunction: Insights into Alzheimer's Disease Mechanisms. Aging Dis 2024; 15:459-479. [PMID: 37548934 PMCID: PMC10917533 DOI: 10.14336/ad.2023.0718] [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: 05/12/2023] [Accepted: 07/18/2023] [Indexed: 08/08/2023] Open
Abstract
Alzheimer's disease (AD) is a devastating neurodegenerative disorder that impacts a substantial number of individuals globally. Despite its widespread prevalence, there is currently no cure for AD. It is widely acknowledged that normal synaptic function holds a key role in memory, cognitive abilities, and the interneuronal transfer of information. As AD advances, symptoms including synaptic impairment, decreased synaptic density, and cognitive decline become increasingly noticeable. The importance of glial cells in the formation of synapses, the growth of neurons, brain maturation, and safeguarding the microenvironment of the central nervous system is well recognized. However, during AD progression, overactive glial cells can cause synaptic dysfunction, neuronal death, and abnormal neuroinflammation. Both neuroinflammation and synaptic dysfunction are present in the early stages of AD. Therefore, focusing on the changes in glia-synapse communication could provide insights into the mechanisms behind AD. In this review, we aim to provide a summary of the role of various glial cells, including microglia, astrocytes, oligodendrocytes, and oligodendrocyte precursor cells, in regulating synaptic dysfunction. This may offer a new perspective on investigating the underlying mechanisms of AD.
Collapse
Affiliation(s)
- Yang Yu
- Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.
| | - Ran Chen
- Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.
- School of Medicine, Sun Yat-sen University, Shenzhen, China.
| | - Kaiyue Mao
- Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.
- School of Medicine, Sun Yat-sen University, Shenzhen, China.
| | - Maoyan Deng
- Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.
- School of Medicine, Sun Yat-sen University, Shenzhen, China.
| | - Zhigang Li
- Scientific Research Center, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, China.
- Shenzhen Key Laboratory of Chinese Medicine Active Substance Screening and Translational Research, Shenzhen, China.
| |
Collapse
|
4
|
Zgorzynska E. TREM2 in Alzheimer's disease: Structure, function, therapeutic prospects, and activation challenges. Mol Cell Neurosci 2024; 128:103917. [PMID: 38244651 DOI: 10.1016/j.mcn.2024.103917] [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: 08/03/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/22/2024] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) is a membrane glycoprotein that plays a crucial role in the regulation of microglial survival, activation, phagocytosis, as well as in the maintenance of brain homeostasis and the inflammatory response to injury or neurodegeneration. This review provides a comprehensive overview of TREM2 structure and functions, highlighting the role of its variants in the development and progression of Alzheimer's disease (AD), a devastating neurodegenerative disease that affects millions of people worldwide. Additionally, the article discusses the potential of TREM2 as a therapeutic target in AD, analyzing the current state of research and future prospects. Given the significant challenges associated with the activation of TREM2, particularly due to its diverse isoforms and the delicate balance required to modulate the immune response without triggering hyperactivation, this review aims to enhance our understanding of TREM2 in AD and inspire further research into this promising yet challenging therapeutic target.
Collapse
Affiliation(s)
- Emilia Zgorzynska
- Department of Cell-to-Cell Communication, Medical University of Lodz, Mazowiecka 6/8, 92-215 Lodz, Poland.
| |
Collapse
|
5
|
Romero-Ramírez L, García-Rama C, Mey J. Janus Kinase Inhibitor Brepocitinib Rescues Myelin Phagocytosis Under Inflammatory Conditions: In Vitro Evidence from Microglia and Macrophage Cell Lines. Mol Neurobiol 2024:10.1007/s12035-024-03963-6. [PMID: 38308667 DOI: 10.1007/s12035-024-03963-6] [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: 08/12/2023] [Accepted: 01/16/2024] [Indexed: 02/05/2024]
Abstract
Central nervous system (CNS) injuries induce cell death and consequently the release of myelin and other cellular debris. Microglia as well as hematogenous macrophages actively collaborate to phagocyte them and undergo their degradation. However, myelin accumulation persists in the lesion site long after the injury with detrimental effects on axonal regeneration. This might be due to the presence of inhibitors of phagocytosis in the injury site. As we recently published that some proinflammatory stimuli, like interferon-γ (IFNγ) and lipopolysaccharide (LPS), inhibit myelin phagocytosis in macrophages, we have now studied the signaling pathways involved. A phagocytosis assay in Raw264.7 macrophages and N13 microglia cell lines with labeled myelin was developed with the pHrodo reagent that emits fluorescence in acidic cellular compartments (e.g.lysosomes). Pharmacological inhibition of Janus kinases (Jak) with Brepocitinib restored myelin phagocytosis and rescued the expression of genes related to phagocytosis, like triggering receptor expressed on myeloid cells 2 (TREM2), induced by IFNγ or LPS. In addition, while pharmacological inhibition of the signal transducer and activator of transcription 3 (STAT3) rescued myelin phagocytosis and the expression of phagocytosis related genes in the presence of LPS, it did not have any effect on IFNγ-treated cells. Our results show that Jak pathways participate in the inhibition of myelin phagocytosis by IFNγ and LPS. They also indicate that the resolution of inflammation is important for the clearance of cellular debris by macrophages and subsequent regenerative processes.
Collapse
Affiliation(s)
- Lorenzo Romero-Ramírez
- Laboratorio de Regeneración Neuronal, Hospital Nacional de Parapléjicos, SESCAM, Finca La Peraleda S/N, 45071, Toledo, Spain.
| | - Concepción García-Rama
- Laboratorio de Regeneración Neuronal, Hospital Nacional de Parapléjicos, SESCAM, Finca La Peraleda S/N, 45071, Toledo, Spain
| | - Jörg Mey
- Laboratorio de Regeneración Neuronal, Hospital Nacional de Parapléjicos, SESCAM, Finca La Peraleda S/N, 45071, Toledo, Spain
- School of Mental Health and Neuroscience, Maastricht University, Maastricht, Netherlands
| |
Collapse
|
6
|
Bosco DB, Kremen V, Haruwaka K, Zhao S, Wang L, Ebner BA, Zheng J, Dheer A, Perry JF, Xie M, Nguyen AT, Worrell GA, Wu LJ. Impaired microglial phagocytosis promotes seizure development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.31.573794. [PMID: 38260601 PMCID: PMC10802340 DOI: 10.1101/2023.12.31.573794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
In the central nervous system, triggering receptor expressed on myeloid cells 2 (TREM2) is exclusively expressed by microglia and is critical for microglial proliferation, migration, and phagocytosis. TREM2 plays an important role in neurodegenerative diseases, such as Alzheimer's disease and amyotrophic lateral sclerosis. However, little is known about the role TREM2 plays in epileptogenesis. To investigate this, we utilized TREM2 knockout (KO) mice within the murine intra-amygdala kainic acid seizure model. Electroencephalographic analysis, immunocytochemistry, and RNA sequencing revealed that TREM2 deficiency significantly promoted seizure-induced pathology. We found that TREM2 KO increased both acute status epilepticus and spontaneous recurrent seizures characteristic of chronic focal epilepsy. Mechanistically, phagocytic clearance of damaged neurons by microglia was impaired in TREM2 KO mice and the reduced phagocytic capacity correlated with increased spontaneous seizures. Analysis of human tissue from patients who underwent surgical resection for drug resistant temporal lobe epilepsy also showed a negative correlation between microglial phagocytic activity and focal to bilateral tonic-clonic generalized seizure history. These results indicate that microglial TREM2 and phagocytic activity may be important to epileptogenesis and the progression of focal temporal lobe epilepsy.
Collapse
Affiliation(s)
- Dale B. Bosco
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
| | - Vaclav Kremen
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
| | | | - Shunyi Zhao
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
| | - Lingxiao Wang
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
| | - Blake A. Ebner
- Department of Laboratory Medicine and Pathology, Mayo Clinic; Rochester, MN, USA
| | - Jiaying Zheng
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
| | - Aastha Dheer
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
| | - Jadyn F. Perry
- Department of Immunology, Mayo Clinic; Rochester, MN, USA
| | - Manling Xie
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
| | - Aivi T. Nguyen
- Department of Laboratory Medicine and Pathology, Mayo Clinic; Rochester, MN, USA
| | | | - Long-Jun Wu
- Department of Neurology, Mayo Clinic; Rochester, MN, USA
- Department of Immunology, Mayo Clinic; Rochester, MN, USA
- Department of Neuroscience, Mayo Clinic; Jacksonville, FL, USA
| |
Collapse
|
7
|
Huang Z. Evidence that Alzheimer's Disease Is a Disease of Competitive Synaptic Plasticity Gone Awry. J Alzheimers Dis 2024; 99:447-470. [PMID: 38669548 PMCID: PMC11119021 DOI: 10.3233/jad-240042] [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] [Indexed: 04/28/2024]
Abstract
Mounting evidence indicates that a physiological function of amyloid-β (Aβ) is to mediate neural activity-dependent homeostatic and competitive synaptic plasticity in the brain. I have previously summarized the lines of evidence supporting this hypothesis and highlighted the similarities between Aβ and anti-microbial peptides in mediating cell/synapse competition. In cell competition, anti-microbial peptides deploy a multitude of mechanisms to ensure both self-protection and competitor elimination. Here I review recent studies showing that similar mechanisms are at play in Aβ-mediated synapse competition and perturbations in these mechanisms underpin Alzheimer's disease (AD). Specifically, I discuss evidence that Aβ and ApoE, two crucial players in AD, co-operate in the regulation of synapse competition. Glial ApoE promotes self-protection by increasing the production of trophic monomeric Aβ and inhibiting its assembly into toxic oligomers. Conversely, Aβ oligomers, once assembled, promote the elimination of competitor synapses via direct toxic activity and amplification of "eat-me" signals promoting the elimination of weak synapses. I further summarize evidence that neuronal ApoE may be part of a gene regulatory network that normally promotes competitive plasticity, explaining the selective vulnerability of ApoE expressing neurons in AD brains. Lastly, I discuss evidence that sleep may be key to Aβ-orchestrated plasticity, in which sleep is not only induced by Aβ but is also required for Aβ-mediated plasticity, underlining the link between sleep and AD. Together, these results strongly argue that AD is a disease of competitive synaptic plasticity gone awry, a novel perspective that may promote AD research.
Collapse
Affiliation(s)
- Zhen Huang
- Departments of Neuroscience and Neurology, University of Wisconsin-Madison, Madison, WI, USA
| |
Collapse
|
8
|
Zhang X, Chen X, Zhang L, Sun Y, Liang Y, Li H, Zhang Y. Role of trigger receptor 2 expressed on myeloid cells in neuroinflammation-neglected multidimensional regulation of microglia. Neurochem Int 2023; 171:105639. [PMID: 37926352 DOI: 10.1016/j.neuint.2023.105639] [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: 08/21/2023] [Revised: 10/01/2023] [Accepted: 11/02/2023] [Indexed: 11/07/2023]
Abstract
Neuroinflammation is an inflammatory cascade involved in various neurological disorders, including Alzheimer's disease, multiple sclerosis, and other relevant diseases. The triggering receptor expressed on myeloid cells 2 (TREM2) is a transmembrane immune receptor that is primarily expressed by microglia in the central nervous system (CNS). While TREM2 is initially believed to be an anti-inflammatory factor in the CNS, increasing evidence suggests that TREM2 plays a more complex role in balancing neuroinflammation. However, the exact mechanism remains unclear. Notably, TREM2 directly regulates microglia inflammation through various signaling pathways. Additionally, studies have suggested that TREM2 mediates microglial phagocytosis, autophagy, metabolism, and microglia phenotypes, which may be involved in the modulation of neuroinflammation. In this review, we aim to discuss the critical role of TREM2 in several microglia functions and the underlying molecular mechanism the modulatory which further mediate neuroinflammation, and elaborate. Finally, we discuss the potential of TREM2 as a therapeutic target in neuroinflammatory disorders.
Collapse
Affiliation(s)
- Xin Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China; Beijing Institute of Hepatology, Beijing Key Laboratory for HIV/AIDS Research, Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Xue Chen
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China; Beijing Institute of Hepatology, Beijing Key Laboratory for HIV/AIDS Research, Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Ling Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Yuqing Sun
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Ying Liang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Huan Li
- Department of Cardiology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Yulin Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China; Beijing Institute of Hepatology, Beijing Key Laboratory for HIV/AIDS Research, Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China.
| |
Collapse
|
9
|
Mackiewicz J, Lisek M, Boczek T. Targeting CaN/NFAT in Alzheimer's brain degeneration. Front Immunol 2023; 14:1281882. [PMID: 38077352 PMCID: PMC10701682 DOI: 10.3389/fimmu.2023.1281882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 11/06/2023] [Indexed: 12/18/2023] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive loss of cognitive functions. While the exact causes of this debilitating disorder remain elusive, numerous investigations have characterized its two core pathologies: the presence of β-amyloid plaques and tau tangles. Additionally, multiple studies of postmortem brain tissue, as well as results from AD preclinical models, have consistently demonstrated the presence of a sustained inflammatory response. As the persistent immune response is associated with neurodegeneration, it became clear that it may also exacerbate other AD pathologies, providing a link between the initial deposition of β-amyloid plaques and the later development of neurofibrillary tangles. Initially discovered in T cells, the nuclear factor of activated T-cells (NFAT) is one of the main transcription factors driving the expression of inflammatory genes and thus regulating immune responses. NFAT-dependent production of inflammatory mediators is controlled by Ca2+-dependent protein phosphatase calcineurin (CaN), which dephosphorylates NFAT and promotes its transcriptional activity. A substantial body of evidence has demonstrated that aberrant CaN/NFAT signaling is linked to several pathologies observed in AD, including neuronal apoptosis, synaptic deficits, and glia activation. In view of this, the role of NFAT isoforms in AD has been linked to disease progression at different stages, some of which are paralleled to diminished cognitive status. The use of classical inhibitors of CaN/NFAT signaling, such as tacrolimus or cyclosporine, or adeno-associated viruses to specifically inhibit astrocytic NFAT activation, has alleviated some symptoms of AD by diminishing β-amyloid neurotoxicity and neuroinflammation. In this article, we discuss the recent findings related to the contribution of CaN/NFAT signaling to the progression of AD and highlight the possible benefits of targeting this pathway in AD treatment.
Collapse
Affiliation(s)
| | | | - Tomasz Boczek
- Department of Molecular Neurochemistry, Medical University of Lodz, Lodz, Poland
| |
Collapse
|
10
|
Mehla J, Deibel SH, Karem H, Hong NS, Hossain SR, Lacoursiere SG, Sutherland RJ, Mohajerani MH, McDonald RJ. Repeated multi-domain cognitive training prevents cognitive decline, anxiety and amyloid pathology found in a mouse model of Alzheimer disease. Commun Biol 2023; 6:1145. [PMID: 37950055 PMCID: PMC10638434 DOI: 10.1038/s42003-023-05506-6] [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: 12/16/2022] [Accepted: 10/25/2023] [Indexed: 11/12/2023] Open
Abstract
Education, occupation, and an active lifestyle, comprising enhanced social, physical, and mental components are associated with improved cognitive functions in aged people and may delay the progression of various neurodegenerative diseases including Alzheimer's disease. To investigate this protective effect, 3-month-old APPNL-G-F/NL-G-F mice were exposed to repeated single- or multi-domain cognitive training. Cognitive training was given at the age of 3, 6, & 9 months. Single-domain cognitive training was limited to a spatial navigation task. Multi-domain cognitive training consisted of a spatial navigation task, object recognition, and fear conditioning. At the age of 12 months, behavioral tests were completed for all groups. Then, mice were sacrificed, and their brains were assessed for pathology. APPNL-G-F/NL-G-F mice given multi-domain cognitive training compared to APPNL-G-F/NL-G-F control group showed an improvement in cognitive functions, reductions in amyloid load and microgliosis, and a preservation of cholinergic function. Additionally, multi-domain cognitive training improved anxiety in APPNL-G-F/NL-G-F mice as evidenced by measuring thigmotaxis behavior in the Morris water maze. There were mild reductions in microgliosis in the brain of APPNL-G-F/NL-G-F mice with single-domain cognitive training. These findings provide causal evidence for the potential of certain forms of cognitive training to mitigate the cognitive deficits in Alzheimer disease.
Collapse
Affiliation(s)
- Jogender Mehla
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Scott H Deibel
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
- Department of Psychology, University of New Brunswick, POB 4400, Fredericton, NB, E3B 3A1, Canada
| | - Hadil Karem
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Nancy S Hong
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Shakhawat R Hossain
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Sean G Lacoursiere
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Robert J Sutherland
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Majid H Mohajerani
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada.
| | - Robert J McDonald
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada.
| |
Collapse
|
11
|
Li Y, Xu H, Wang H, Yang K, Luan J, Wang S. TREM2: Potential therapeutic targeting of microglia for Alzheimer's disease. Biomed Pharmacother 2023; 165:115218. [PMID: 37517293 DOI: 10.1016/j.biopha.2023.115218] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/20/2023] [Accepted: 07/21/2023] [Indexed: 08/01/2023] Open
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease, resulting in the loss of cognitive ability and memory. However, there is no specific treatment to mechanistically inhibit the progression of Alzheimer's disease, and most drugs only provide symptom relief and do not fundamentally reverse AD. Current studies show that triggering receptor expressed on myeloid cells 2 (TREM2) is predominantly expressed in microglia of the central nervous system (CNS) and is involved in microglia proliferation, survival, migration and phagocytosis. The current academic view suggests that TREM2 and its ligands have CNS protective effects in AD. Specifically, TREM2 acts by regulating the function of microglia and promoting the clearance of neuronal toxic substances and abnormal proteins by microglia. In addition, TREM2 is also involved in regulating inflammatory response and cell signaling pathways, affecting the immune response and regulatory role of microglia. Although the relationship between TREM2 and Alzheimer's disease has been extensively studied, its specific mechanism of action is not fully understood. The purpose of this review is to provide a comprehensive analysis of the research of TREM2, including its regulation of the inflammatory response, lipid metabolism and phagocytosis in microglia of CNS in AD, and to explore the potential application prospects as well as limitations of targeting TREM2 for the treatment of AD.
Collapse
Affiliation(s)
- Yueran Li
- Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui Province, China
| | - Huifang Xu
- Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui Province, China
| | - Huifang Wang
- Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui Province, China
| | - Kui Yang
- Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui Province, China
| | - Jiajie Luan
- Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui Province, China
| | - Sheng Wang
- Department of Pharmacy, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, Anhui Province, China.
| |
Collapse
|
12
|
Thu VTA, Hoang TX, Kim JY. 1,25-Dihydroxy Vitamin D 3 Facilitates the M2 Polarization and β-Amyloid Uptake by Human Microglia in a TREM2-Dependent Manner. BIOMED RESEARCH INTERNATIONAL 2023; 2023:3483411. [PMID: 37274074 PMCID: PMC10239306 DOI: 10.1155/2023/3483411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/23/2023] [Accepted: 05/17/2023] [Indexed: 06/06/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by dementia as the primary clinical symptom. The production and accumulation of aggregated β-amyloid (Aβ) in patient brain tissues is one of the hallmarks of AD pathogenesis. Microglia, brain-resident macrophages, produce inflammatory cytokines in response to Aβ oligomers or fibrils exacerbating Aβ pathology in AD. HMO6 cells were treated with Aβ42 in the presence or absence of 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) to determine its potential immunomodulatory effects, and the expression of pro-/anti-inflammatory cytokines, M1/M2-associated markers, Toll-like receptors (TLRs), and triggering receptor expressed on myeloid cells 2 (TREM2) was examined. 1,25(OH)2D3 was found to suppress Aβ-induced expression of proinflammatory cytokines (TNF-α, IL-1β, and IL-6), M1 markers (CD86 and iNOS), and TLR2/4, whilst increasing the expression of anti-inflammatory cytokines (IL-4, IL-10, and CCL17) and M2 markers (CD206 and Arg-1). Furthermore, 1,25(OH)2D3 promoted TREM2 expression and Aβ uptake by HMO6 cells, and the enhancement of Aβ uptake and M2 polarization was revealed to be TREM2-dependent. The findings of this study suggest that 1,25(OH)2D3 facilitates M2 polarization and Aβ uptake in a TREM2-dependent manner.
Collapse
Affiliation(s)
- Vo Thuy Anh Thu
- Department of Life Science, Gachon University, Seongnam, Gyeonggi-do 13120, Republic of Korea
| | - Thi Xoan Hoang
- Department of Life Science, Gachon University, Seongnam, Gyeonggi-do 13120, Republic of Korea
| | - Jae Young Kim
- Department of Life Science, Gachon University, Seongnam, Gyeonggi-do 13120, Republic of Korea
| |
Collapse
|
13
|
Lefterov I, Fitz NF, Lu Y, Koldamova R. APOEε4 and risk of Alzheimer's disease - time to move forward. Front Neurosci 2023; 17:1195724. [PMID: 37274212 PMCID: PMC10235508 DOI: 10.3389/fnins.2023.1195724] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/02/2023] [Indexed: 06/06/2023] Open
Abstract
The inheritance of Apolipoprotein E4 (APOEε4) brings the highest genetic risk of Alzheimer's disease (AD), arguably the highest genetic risk in human pathology. Since the discovery of the association, APOE protein isoforms have been at the center of tens of thousands of studies and reports. While, without a doubt, our knowledge about the normal physiological function of APOE isoforms in the brain has increased tremendously, the questions of how the inheritance of the APOEε4 allele translates into a risk of AD, and the risk is materialized, remain unanswered. Moreover, the knowledge about the risk associated with APOEε4 has not helped design a meaningful preventative or therapeutic strategy. Animal models with targeted replacement of Apoe have been generated and, thanks to the recent NIH/NIA/Alzheimer's disease Association initiative, are now freely available to AD researchers. While helpful in many aspects, none of the available models recapitulates normal physiological transcriptional regulation of the human APOE gene cluster. Changes in epigenetic regulation of APOE alleles in animal models in response to external insults have rarely been if ever, addressed. However, these animal models provide a useful tool to handle questions and investigate protein-protein interactions with proteins expressed by other recently discovered genes and gene variants considered genetic risk factors of AD, like Triggering Receptor expressed on Myeloid cells 2 (TREM2). In this review, we discuss genetic and epigenetic regulatory mechanisms controlling and influencing APOE expression and focus on interactions of APOE and TREM2 in the context of microglia and astrocytes' role in AD-like pathology in animal models.
Collapse
|
14
|
Park MD, Reyes-Torres I, LeBerichel J, Hamon P, LaMarche NM, Hegde S, Belabed M, Troncoso L, Grout JA, Magen A, Humblin E, Nair A, Molgora M, Hou J, Newman JH, Farkas AM, Leader AM, Dawson T, D'Souza D, Hamel S, Sanchez-Paulete AR, Maier B, Bhardwaj N, Martin JC, Kamphorst AO, Kenigsberg E, Casanova-Acebes M, Horowitz A, Brown BD, De Andrade LF, Colonna M, Marron TU, Merad M. TREM2 macrophages drive NK cell paucity and dysfunction in lung cancer. Nat Immunol 2023; 24:792-801. [PMID: 37081148 PMCID: PMC11088947 DOI: 10.1038/s41590-023-01475-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 02/23/2023] [Indexed: 04/22/2023]
Abstract
Natural killer (NK) cells are commonly reduced in human tumors, enabling many to evade surveillance. Here, we sought to identify cues that alter NK cell activity in tumors. We found that, in human lung cancer, the presence of NK cells inversely correlated with that of monocyte-derived macrophages (mo-macs). In a murine model of lung adenocarcinoma, we show that engulfment of tumor debris by mo-macs triggers a pro-tumorigenic program governed by triggering receptor expressed on myeloid cells 2 (TREM2). Genetic deletion of Trem2 rescued NK cell accumulation and enabled an NK cell-mediated regression of lung tumors. TREM2+ mo-macs reduced NK cell activity by modulating interleukin (IL)-18/IL-18BP decoy interactions and IL-15 production. Notably, TREM2 blockade synergized with an NK cell-activating agent to further inhibit tumor growth. Altogether, our findings identify a new axis, in which TREM2+ mo-macs suppress NK cell accumulation and cytolytic activity. Dual targeting of macrophages and NK cells represents a new strategy to boost antitumor immunity.
Collapse
Affiliation(s)
- Matthew D Park
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ivan Reyes-Torres
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jessica LeBerichel
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Pauline Hamon
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Nelson M LaMarche
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Thoracic Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Samarth Hegde
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Meriem Belabed
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Leanna Troncoso
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - John A Grout
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Assaf Magen
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Etienne Humblin
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Achuth Nair
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Martina Molgora
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jinchao Hou
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jenna H Newman
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Division of Hematology/Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Adam M Farkas
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Division of Hematology/Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Andrew M Leader
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA
| | - Travis Dawson
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Human Immune Monitoring Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Darwin D'Souza
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Human Immune Monitoring Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Steven Hamel
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Alfonso Rodriguez Sanchez-Paulete
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Barbara Maier
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Nina Bhardwaj
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Division of Hematology/Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jerome C Martin
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- CHU Nantes, Laboratoire d'Immunologie, Center for ImmunoMonitoring Nantes-Atlantique (CIMNA), Nantes, France
| | - Alice O Kamphorst
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ephraim Kenigsberg
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Maria Casanova-Acebes
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Cancer Immunity Laboratory, Molecular Oncology Program, Spanish National Cancer Center (CNIO), Madrid, Spain
| | - Amir Horowitz
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Brian D Brown
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lucas Ferrari De Andrade
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Thomas U Marron
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Thoracic Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Division of Hematology/Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Miriam Merad
- Marc and Jennifer Lipschultz Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Center for Thoracic Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Human Immune Monitoring Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| |
Collapse
|
15
|
Bravo DD, Shi Y, Sheu A, Liang WC, Lin W, Wu Y, Yan M, Wang J. A Real-Time Image-Based Efferocytosis Assay for the Discovery of Functionally Inhibitory Anti-MerTK Antibodies. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:1166-1176. [PMID: 36881873 PMCID: PMC10067786 DOI: 10.4049/jimmunol.2200597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 02/12/2023] [Indexed: 03/09/2023]
Abstract
Efferocytosis is a phagocytic process by which apoptotic cells are cleared by professional and nonprofessional phagocytic cells. In tumors, efferocytosis of apoptotic cancer cells by tumor-associated macrophages prevents Ag presentation and suppresses the host immune response against the tumor. Therefore, reactivating the immune response by blockade of tumor-associated macrophage-mediated efferocytosis is an attractive strategy for cancer immunotherapy. Even though several methods have been developed to monitor efferocytosis, an automated and high-throughput quantitative assay should offer highly desirable advantages for drug discovery. In this study, we describe a real-time efferocytosis assay with an imaging system for live-cell analysis. Using this assay, we successfully discovered potent anti-MerTK Abs that block tumor-associated macrophage-mediated efferocytosis in mice. Furthermore, we used primary human and cynomolgus monkey macrophages to identify and characterize anti-MerTK Abs for potential clinical development. By studying the phagocytic activities of different types of macrophages, we demonstrated that our efferocytosis assay is robust for screening and characterization of drug candidates that inhibit unwanted efferocytosis. Moreover, our assay is also applicable to investigating the kinetics and molecular mechanisms of efferocytosis/phagocytosis.
Collapse
Affiliation(s)
- Daniel D. Bravo
- Department of Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, CA
| | - Yongchang Shi
- Department of Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, CA
| | - Allison Sheu
- Department of Molecular and Cellular Biology, University of California, Berkeley, Berkeley, CA
| | - Wei-Ching Liang
- Department of Antibody Engineering, Genentech, Inc., South San Francisco, CA
| | - WeiYu Lin
- Department of Antibody Engineering, Genentech, Inc., South San Francisco, CA
| | - Yan Wu
- Department of Antibody Engineering, Genentech, Inc., South San Francisco, CA
| | - Minhong Yan
- Department of Molecular Oncology, Genentech, Inc., South San Francisco, CA
| | - Jianyong Wang
- Department of Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, CA
| |
Collapse
|
16
|
Lau V, Ramer L, Tremblay MÈ. An aging, pathology burden, and glial senescence build-up hypothesis for late onset Alzheimer's disease. Nat Commun 2023; 14:1670. [PMID: 36966157 PMCID: PMC10039917 DOI: 10.1038/s41467-023-37304-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 03/07/2023] [Indexed: 03/27/2023] Open
Abstract
Alzheimer's disease (AD) predominantly occurs as a late onset (LOAD) form involving neurodegeneration and cognitive decline with progressive memory loss. Risk factors that include aging promote accumulation of AD pathologies, such as amyloid-beta and tau aggregates, as well as inflammation and oxidative stress. Homeostatic glial states regulate and suppress pathology buildup; inflammatory states exacerbate pathology by releasing pro-inflammatory cytokines. Multiple stresses likely induce glial senescence, which could decrease supportive functions and reinforce inflammation. In this perspective, we hypothesize that aging first drives AD pathology burden, whereafter AD pathology putatively induces glial senescence in LOAD. We hypothesize that increasing glial senescence, particularly local senescent microglia accumulation, sustains and drives perpetuating buildup and spread of AD pathologies, glial aging, and further senescence. We predict that increasing glial senescence, particularly local senescent microglia accumulation, also transitions individuals from healthy cognition into mild cognitive impairment and LOAD diagnosis. These pathophysiological underpinnings may centrally contribute to LOAD onset, but require further mechanistic investigation.
Collapse
Affiliation(s)
- Victor Lau
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
| | - Leanne Ramer
- Department of Biomedical Physiology & Kinesiology, Simon Fraser University, Burnaby, BC, Canada.
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
- Axe Neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada.
- Département de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec, QC, Canada.
- The Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada.
- Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada.
| |
Collapse
|
17
|
Damisah EC, Rai A, Hill RA, Tong L, Grutzendler J. TREM2 and APOE do not modulate phagocytic clearance of dying cells in the live mammalian brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.17.533222. [PMID: 36993245 PMCID: PMC10055304 DOI: 10.1101/2023.03.17.533222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
TREM2 and APOE are two major risk factors for Alzheimer's disease (AD) that have been proposed to play crucial roles in microglia pathophysiology by affecting their ability to phagocytose cellular debris or aggregated proteins. In this study, we investigated for the first time the impact of TREM2 and APOE on the removal of dying neurons in the live brain by implementing a targeted photochemical method for programmed cell death induction combined with high-resolution two-photon imaging. Our findings showed that the deletion of either TREM2 or APOE did not affect the dynamics of microglia engagement with dying neurons or their efficiency in phagocytosing corpses. Interestingly, while microglia that encapsulate amyloid deposits were capable of phagocytosing dying cells without disengaging from plaques or moving their cell bodies; in the absence of TREM2, microglia cell bodies were observed to readily migrate towards dying cells, further disengaging from plaques. Our data suggest that TREM2 and APOE variants are unlikely to increase risk of AD through impaired corpse phagocytosis.
Collapse
Affiliation(s)
- Eyiyemisi C Damisah
- Department of Neurosurgery, Yale School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, USA
- Wu Tsai Institute, Yale University, New Haven, CT, USA
- contributed equally to this work
| | - Anupama Rai
- Department of Neurology, Yale School of Medicine, New Haven, CT, USA
- contributed equally to this work
| | - Robert A Hill
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire
- contributed equally to this work
| | - Lei Tong
- Department of Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Jaime Grutzendler
- Department of Neurology, Yale School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale School of Medicine, New Haven, CT, USA
- Wu Tsai Institute, Yale University, New Haven, CT, USA
| |
Collapse
|
18
|
Ge J, Koutarapu S, Jha D, Dulewicz M, Zetterberg H, Blennow K, Hanrieder J. Tetramodal Chemical Imaging Delineates the Lipid-Amyloid Peptide Interplay at Single Plaques in Transgenic Alzheimer's Disease Models. Anal Chem 2023; 95:4692-4702. [PMID: 36856542 PMCID: PMC10018455 DOI: 10.1021/acs.analchem.2c05302] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 02/16/2023] [Indexed: 03/02/2023]
Abstract
Beta-amyloid (Aβ) plaque pathology is one of the most prominent histopathological feature of Alzheimer's disease (AD). The exact pathogenic mechanisms linking Aβ to AD pathogenesis remain however not fully understood. Recent advances in amyloid-targeting pharmacotherapies highlight the critical relevance of Aβ aggregation for understanding the molecular basis of AD pathogenesis. We developed a novel, integrated, tetramodal chemical imaging paradigm for acquisition of trimodal mass spectrometry imaging (MSI) and interlaced fluorescent microscopy from a single tissue section. We used this approach to comprehensively investigate lipid-Aβ correlates at single plaques in two different mouse models of AD (tgAPPSwe and tgAPPArcSwe) with varying degrees of intrinsic properties affecting amyloid aggregation. Integration of the multimodal imaging data and multivariate data analysis identified characteristic patterns of plaque-associated lipid- and peptide localizations across both mouse models. Correlative fluorescence microscopy using structure-sensitive amyloid probes identified intra-plaque structure-specific lipid- and Aβ patterns, including Aβ 1-40 and Aβ 1-42 along with gangliosides (GM), phosphoinositols (PI), conjugated ceramides (CerP and PE-Cer), and lysophospholipids (LPC, LPA, and LPI). Single plaque correlation analysis across all modalities further revealed how these distinct lipid species were associated with Aβ peptide deposition across plaque heterogeneity, indicating different roles for those lipids in plaque growth and amyloid fibrillation, respectively. Here, conjugated ceramide species correlated with Aβ core formation indicating their involvement in initial plaque seeding or amyloid maturation. In contrast, LPI and PI were solely correlated with general plaque growth. In addition, GM1 and LPC correlated with continuous Aβ deposition and maturation. The results highlight the potential of this comprehensive multimodal imaging approach and implement distinct lipids in amyloidogenic proteinopathy.
Collapse
Affiliation(s)
- Junyue Ge
- Department
of Psychiatry and Neurochemistry, Sahlgrenska
Academy at the University of Gothenburg, Mölndal Hospital, House V3, SE-431 80 Mölndal, Sweden
| | - Srinivas Koutarapu
- Department
of Psychiatry and Neurochemistry, Sahlgrenska
Academy at the University of Gothenburg, Mölndal Hospital, House V3, SE-431 80 Mölndal, Sweden
| | - Durga Jha
- Department
of Psychiatry and Neurochemistry, Sahlgrenska
Academy at the University of Gothenburg, Mölndal Hospital, House V3, SE-431 80 Mölndal, Sweden
| | - Maciej Dulewicz
- Department
of Psychiatry and Neurochemistry, Sahlgrenska
Academy at the University of Gothenburg, Mölndal Hospital, House V3, SE-431 80 Mölndal, Sweden
| | - Henrik Zetterberg
- Department
of Psychiatry and Neurochemistry, Sahlgrenska
Academy at the University of Gothenburg, Mölndal Hospital, House V3, SE-431 80 Mölndal, Sweden
- Clinical
Neurochemistry Laboratory, Sahlgrenska University
Hospital, Mölndal
Hospital, House V3, SE-431 80 Mölndal, Sweden
- Department
of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
- UK
Dementia Research Institute at University College London, Queen Square, London WC1N 3BG, United Kingdom
- Hong
Kong Center for Neurodegenerative Diseases, Hong Kong 1512-1518, China
- Wisconsin
Alzheimer’s Disease Research Center, University of Wisconsin School of Medicine and Public Health, University
of Wisconsin-Madison, Madison, Wisconsin 53726, United States
| | - Kaj Blennow
- Department
of Psychiatry and Neurochemistry, Sahlgrenska
Academy at the University of Gothenburg, Mölndal Hospital, House V3, SE-431 80 Mölndal, Sweden
- Clinical
Neurochemistry Laboratory, Sahlgrenska University
Hospital, Mölndal
Hospital, House V3, SE-431 80 Mölndal, Sweden
| | - Jörg Hanrieder
- Department
of Psychiatry and Neurochemistry, Sahlgrenska
Academy at the University of Gothenburg, Mölndal Hospital, House V3, SE-431 80 Mölndal, Sweden
- Clinical
Neurochemistry Laboratory, Sahlgrenska University
Hospital, Mölndal
Hospital, House V3, SE-431 80 Mölndal, Sweden
- Department
of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
| |
Collapse
|
19
|
Wang X, He Q, Zhou C, Xu Y, Liu D, Fujiwara N, Kubota N, Click A, Henderson P, Vancil J, Marquez CA, Gunasekaran G, Schwartz ME, Tabrizian P, Sarpel U, Fiel MI, Diao Y, Sun B, Hoshida Y, Liang S, Zhong Z. Prolonged hypernutrition impairs TREM2-dependent efferocytosis to license chronic liver inflammation and NASH development. Immunity 2023; 56:58-77.e11. [PMID: 36521495 PMCID: PMC9839616 DOI: 10.1016/j.immuni.2022.11.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 08/12/2022] [Accepted: 11/22/2022] [Indexed: 12/15/2022]
Abstract
Obesity-induced chronic liver inflammation is a hallmark of nonalcoholic steatohepatitis (NASH)-an aggressive form of nonalcoholic fatty liver disease. However, it remains unclear how such a low-grade, yet persistent, inflammation is sustained in the liver. Here, we show that the macrophage phagocytic receptor TREM2, induced by hepatocyte-derived sphingosine-1-phosphate, was required for efferocytosis of lipid-laden apoptotic hepatocytes and thereby maintained liver immune homeostasis. However, prolonged hypernutrition led to the production of proinflammatory cytokines TNF and IL-1β in the liver to induce TREM2 shedding through ADAM17-dependent proteolytic cleavage. Loss of TREM2 resulted in aberrant accumulation of dying hepatocytes, thereby further augmenting proinflammatory cytokine production. This ultimately precipitated a vicious cycle that licensed chronic inflammation to drive simple steatosis transition to NASH. Therefore, impaired macrophage efferocytosis is a previously unrecognized key pathogenic event that enables chronic liver inflammation in obesity. Blocking TREM2 cleavage to restore efferocytosis may represent an effective strategy to treat NASH.
Collapse
Affiliation(s)
- Xiaochen Wang
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Qifeng He
- Department of General Surgery, Nanjing First Hospital, The Affiliated Nanjing Hospital of Nanjing Medical University, Nanjing 210006, Jiangsu, China
| | - Chuanli Zhou
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yueyuan Xu
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA; Duke Regeneration Center, Center for Advanced Genomic Technologies, Duke University Medical Center, Durham, NC 27710, USA
| | - Danhui Liu
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Naoto Fujiwara
- Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Naoto Kubota
- Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Arielle Click
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Polly Henderson
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Janiece Vancil
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Cesia Ammi Marquez
- Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ganesh Gunasekaran
- Department of Surgery, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Myron E Schwartz
- Department of Surgery, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Parissa Tabrizian
- Department of Surgery, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Umut Sarpel
- Department of Surgery, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Maria Isabel Fiel
- Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yarui Diao
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA; Duke Regeneration Center, Center for Advanced Genomic Technologies, Duke University Medical Center, Durham, NC 27710, USA
| | - Beicheng Sun
- Department of Hepatobiliary Surgery, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, Jiangsu, China
| | - Yujin Hoshida
- Division of Digestive and Liver Diseases, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shuang Liang
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Zhenyu Zhong
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
20
|
Fracassi A, Marcatti M, Tumurbaatar B, Woltjer R, Moreno S, Taglialatela G. TREM2-induced activation of microglia contributes to synaptic integrity in cognitively intact aged individuals with Alzheimer's neuropathology. Brain Pathol 2023; 33:e13108. [PMID: 35816404 PMCID: PMC9836373 DOI: 10.1111/bpa.13108] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 06/16/2022] [Indexed: 01/21/2023] Open
Abstract
The existence of individuals who remain cognitively intact despite presenting histopathological signs of Alzheimer's disease (AD), here referred to as "Nondemented with AD neuropathology" (NDAN), suggests that some mechanisms are triggered to resist cognitive impairment. Exposed phosphatidylserine (ePS) represents a neuronal "eat-me" signal involved in microglial-mediated phagocytosis of damaged synapses. A possible mediator of this process is TREM2, a microglial surface receptor activated by ligands including PS. Based on TREM2 role in the scavenging function of microglia, we hypothesize that an efficient microglial phagocytosis of damaged synapses underlies synaptic resilience in NDAN, thus protecting from memory deficits. Using immunofluorescence microscopy, we performed a comparative study of human post-mortem frontal cortices of aged-matched, AD and NDAN individuals. We studied the distribution of activated microglia (IBA1, IBA1+ /CD68+ cells) and phagocytic microglia-related proteins (TREM2, DAP12), demonstrating higher microglial activation and TREM2 expression in NDAN versus AD. A study of the preservation of synapses around plaques, assessed using MAP2 and βIII tubulin as dendritic and axonal markers, respectively, and PSD95 as a postsynaptic marker, revealed preserved axonal/dendritic structure around plaques in NDAN versus AD. Moreover, high levels of PSD95 around NDAN plaques and the colocalization of PSD95 with CD68 indicated a prompt removal of damaged synapses by phagocytic microglia. Furthermore, Annexin V assay on aged-matched, AD and NDAN individuals synaptosomes revealed increased levels of ePS in NDAN, confirming damaged synapses engulfment. Our results suggest a higher efficiency of TREM2-induced phagocytic microglia in removing damaged synapses, underlying synaptic resilience in NDAN individuals.
Collapse
Affiliation(s)
- Anna Fracassi
- Mitchell Center for Neurodegenerative Diseases, Department of NeurologyUniversity of Texas Medical Branch (UTMB)GalvestonTexasUSA
| | - Michela Marcatti
- Mitchell Center for Neurodegenerative Diseases, Department of NeurologyUniversity of Texas Medical Branch (UTMB)GalvestonTexasUSA
| | - Batbayar Tumurbaatar
- Mitchell Center for Neurodegenerative Diseases, Department of NeurologyUniversity of Texas Medical Branch (UTMB)GalvestonTexasUSA
| | - Randall Woltjer
- Department of PathologyOregon Health and Science UniversityPortlandOregonUSA
| | - Sandra Moreno
- Department of Science, LIMEUniversity Roma TreRomeItaly
| | - Giulio Taglialatela
- Mitchell Center for Neurodegenerative Diseases, Department of NeurologyUniversity of Texas Medical Branch (UTMB)GalvestonTexasUSA
| |
Collapse
|
21
|
Zhang W, Chen Y, Pei H. C1q and central nervous system disorders. Front Immunol 2023; 14:1145649. [PMID: 37033981 PMCID: PMC10076750 DOI: 10.3389/fimmu.2023.1145649] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/07/2023] [Indexed: 04/11/2023] Open
Abstract
C1q is a crucial component of the complement system, which is activated through the classical pathway to perform non-specific immune functions, serving as the first line of defense against pathogens. C1q can also bind to specific receptors to carry out immune and other functions, playing a vital role in maintaining immune homeostasis and normal physiological functions. In the developing central nervous system (CNS), C1q functions in synapse formation and pruning, serving as a key player in the development and homeostasis of neuronal networks in the CNS. C1q has a close relationship with microglia and astrocytes, and under their influence, C1q may contribute to the development of CNS disorders. Furthermore, C1q can also have independent effects on neurological disorders, producing either beneficial or detrimental outcomes. Most of the evidence for these functions comes from animal models, with some also from human specimen studies. C1q is now emerging as a promising target for the treatment of a variety of diseases, and clinical trials are already underway for CNS disorders. This article highlights the role of C1q in CNS diseases, offering new directions for the diagnosis and treatment of these conditions.
Collapse
Affiliation(s)
- Wenjie Zhang
- Department of Emergency Intensive Care Unit, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Department of General Practice, Xingyang Sishui Central Health Center, Zhengzhou, China
| | - Yuan Chen
- Department of Neurology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Hui Pei
- Department of Emergency Intensive Care Unit, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- *Correspondence: Hui Pei,
| |
Collapse
|
22
|
Han RT, Vainchtein ID, Schlachetzki JC, Cho FS, Dorman LC, Ahn E, Kim DK, Barron JJ, Nakao-Inoue H, Molofsky AB, Glass CK, Paz JT, Molofsky AV. Microglial pattern recognition via IL-33 promotes synaptic refinement in developing corticothalamic circuits in mice. J Exp Med 2022; 220:213758. [PMID: 36520518 PMCID: PMC9757845 DOI: 10.1084/jem.20220605] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 09/21/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
Microglia are critical regulators of brain development that engulf synaptic proteins during postnatal synapse remodeling. However, the mechanisms through which microglia sense the brain environment are not well defined. Here, we characterized the regulatory program downstream of interleukin-33 (IL-33), a cytokine that promotes microglial synapse remodeling. Exposing the developing brain to a supraphysiological dose of IL-33 altered the microglial enhancer landscape and increased binding of stimulus-dependent transcription factors including AP-1/FOS. This induced a gene expression program enriched for the expression of pattern recognition receptors, including the scavenger receptor MARCO. CNS-specific deletion of IL-33 led to increased excitatory/inhibitory synaptic balance, spontaneous absence-like epileptiform activity in juvenile mice, and increased seizure susceptibility in response to chemoconvulsants. We found that MARCO promoted synapse engulfment, and Marco-deficient animals had excess thalamic excitatory synapses and increased seizure susceptibility. Taken together, these data define coordinated epigenetic and functional changes in microglia and uncover pattern recognition receptors as potential regulators of postnatal synaptic refinement.
Collapse
Affiliation(s)
- Rafael T. Han
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA,Rafael T. Han:
| | - Ilia D. Vainchtein
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | | | - Frances S. Cho
- Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA, USA,Department of Neurology, University of California, San Francisco, San Francisco, CA, USA,Gladstone Institute of Neurological Disease, San Francisco, CA, USA
| | - Leah C. Dorman
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA,Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA, USA
| | - Eunji Ahn
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Dong Kyu Kim
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Jerika J. Barron
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Hiromi Nakao-Inoue
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA
| | - Ari B. Molofsky
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Christopher K. Glass
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA,Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Jeanne T. Paz
- Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA, USA,Department of Neurology, University of California, San Francisco, San Francisco, CA, USA,Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, USA,Gladstone Institute of Neurological Disease, San Francisco, CA, USA
| | - Anna V. Molofsky
- Departments of Psychiatry and Behavioral Sciences/Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA,Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA, USA,Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA, USA,Correspondence to Anna V. Molofsky:
| |
Collapse
|
23
|
Boudesco C, Nonneman A, Cinti A, Picardi P, Redaelli L, Swijsen S, Roewe J, Reinhardt P, Ibach M, Walter J, Pocock JM, Ren Y, Driguez P, Dargazanli G, Eyquem S, Proto J, Flores‐Morales A, Pradier L. Novel potent liposome agonists of triggering receptor expressed on myeloid cells 2 phenocopy antibody treatment in cells. Glia 2022; 70:2290-2308. [PMID: 35912412 PMCID: PMC9804933 DOI: 10.1002/glia.24252] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 07/08/2022] [Accepted: 07/15/2022] [Indexed: 01/09/2023]
Abstract
The receptor Triggering Receptor Expressed on Myeloid cells 2 (TREM2) is associated with several neurodegenerative diseases including Alzheimer's Disease and TREM2 stimulation represents a novel therapeutic opportunity. TREM2 can be activated by antibodies targeting the stalk region, most likely through receptor dimerization. Endogenous ligands of TREM2 are suggested to be negatively charged apoptotic bodies, mimicked by phosphatidylserine incorporated in liposomes and other polyanionic molecules likely binding to TREM2 IgV fold. However, there has been much discrepancy in the literature on the nature of phospholipids (PLs) that can activate TREM2 and on the stability of the corresponding liposomes over time. We describe optimized liposomes as robust agonists selective for TREM2 over TREM1 in cellular system. The detailed structure/activity relationship studies of lipid polar heads indicate that negatively charged lipid heads are required for activity and we identified the shortest maximally active PL sidechain. Optimized liposomes are active on both TREM2 common variant and TREM2 R47H mutant. Activity and selectivity were further confirmed in different native TREM2 expressing cell types including on integrated cellular responses such as stimulation of phagocytic activity. Such tool agonists will be useful in further studies of TREM2 biology in cellular systems alongside antibodies, and in the design of small molecule synthetic TREM2 agonists.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Julian Roewe
- Neuroscience DiscoveryAbbVie Deutschland GmbH & Co. KGLudwigshafenGermany
| | - Peter Reinhardt
- Neuroscience DiscoveryAbbVie Deutschland GmbH & Co. KGLudwigshafenGermany
| | - Melanie Ibach
- Department of NeurologyUniversity of BonnBonnGermany
| | - Jochen Walter
- Department of NeurologyUniversity of BonnBonnGermany
| | - Jennifer M. Pocock
- Department of NeuroinflammationUniversity College London, Queen Square Institute of NeurologyLondonUK
| | - Yi Ren
- Rare and Neurology TASanofiFraminghamMassachusettsUSA
| | | | | | | | | | | | | |
Collapse
|
24
|
Ogaki A, Ikegaya Y, Koyama R. Replacement of Mouse Microglia With Human Induced Pluripotent Stem Cell (hiPSC)-Derived Microglia in Mouse Organotypic Slice Cultures. Front Cell Neurosci 2022; 16:918442. [PMID: 35910250 PMCID: PMC9325970 DOI: 10.3389/fncel.2022.918442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 06/20/2022] [Indexed: 11/24/2022] Open
Abstract
Microglia, the major immune cells in the brain, are reported to differ in gene expression patterns among species. Therefore, it would be preferable in some cases to use human microglia rather than mouse microglia in microglia-targeted disease research. In the past half a decade, researchers have developed in vivo transplantation methods in which human induced pluripotent stem cell-derived microglia (hiPSC-MG) are transplanted into a living mouse brain. However, in vivo transplantation methods are not necessarily accessible to all researchers due to the difficulty of obtaining the materials needed and the transplantation technique itself. In addition, for in vivo systems for microglia-targeted drug screening, it is difficult to control the pharmacokinetics, especially blood-brain barrier permeability. Therefore, in addition to existing in vivo transplantation systems, the development of an ex vivo transplantation system would help to further evaluate the properties of hiPSC-MG. In this study, we aimed to establish a method to efficiently transplant hiPSC-MG into cultured mouse hippocampal slices. We found that approximately 80% of the total microglia in a cultured slice were replaced by hiPSC-derived microglia when innate microglia were pharmacologically removed prior to transplantation. Furthermore, when neuronal death was induced by applying Kainic acid (KA) to slice cultures, transplanted hiPSC-MG changed their morphology and phagocytosed cell debris. Thus, this study provides a method to transplant hiPSC-MG into the mouse hippocampal slice cultures with a high replacement rate. Because the transplanted microglia survived and exerted phagocytic functions, this method will be useful for evaluating the properties of hiPSC-MG ex vivo.
Collapse
Affiliation(s)
- Ari Ogaki
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Bunkyo, Japan
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Suita, Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Bunkyo, Japan
- *Correspondence: Ryuta Koyama
| |
Collapse
|
25
|
Gallo C, Manzo E, Barra G, Fioretto L, Ziaco M, Nuzzo G, d'Ippolito G, Ferrera F, Contini P, Castiglia D, Angelini C, De Palma R, Fontana A. Sulfavant A as the first synthetic TREM2 ligand discloses a homeostatic response of dendritic cells after receptor engagement. Cell Mol Life Sci 2022; 79:369. [PMID: 35723745 PMCID: PMC9207826 DOI: 10.1007/s00018-022-04297-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 03/18/2022] [Accepted: 04/08/2022] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The immune response arises from a fine balance of mechanisms that provide for surveillance, tolerance, and elimination of dangers. Sulfavant A (SULF A) is a sulfolipid with a promising adjuvant activity. Here we studied the mechanism of action of SULF A and addressed the identification of its molecular target in human dendritic cells (hDCs). METHODS Adjuvant effect and immunological response to SULF A were assessed on DCs derived from human donors. In addition to testing various reporter cells, target identification and downstream signalling was supported by a reverse pharmacology approach based on antibody blocking and gene silencing, crosstalk with TLR pathways, use of human allogeneic mixed lymphocyte reaction. RESULTS SULF A binds to the Triggering Receptor Expressed on Myeloid cells-2 (TREM2) and initiates an unconventional maturation of hDCs leading to enhanced migration activity and up-regulation of MHC and co-stimulatory molecules without release of conventional cytokines. This response involves the SYK-NFAT axis and is compromised by blockade or gene silencing of TREM2. Activation by SULF A preserved the DC functions to excite the allogeneic T cell response, and increased interleukin-10 release after lipopolysaccharide stimulation. CONCLUSION SULF A is the first synthetic small molecule that binds to TREM2. The receptor engagement drives differentiation of an unprecedented DC phenotype (homeDCs) that contributes to immune homeostasis without compromising lymphocyte activation and immunogenic response. This mechanism fully supports the adjuvant and immunoregulatory activity of SULF A. We also propose that the biological properties of SULF A can be of interest in various physiopathological mechanisms and therapies involving TREM2.
Collapse
Affiliation(s)
- Carmela Gallo
- Consiglio Nazionale delle Ricerche, Istituto di Chimica Biomolecolare, Via Campi Flegrei 34, 80078, Pozzuoli, Napoli, Italy.
| | - Emiliano Manzo
- Bio-Organic Chemistry Unit, Institute of Bio-Molecular Chemistry, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Italy
| | - Giusi Barra
- Bio-Organic Chemistry Unit, Institute of Bio-Molecular Chemistry, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Italy
| | - Laura Fioretto
- Consorzio Italbiotec, Via Fantoli, 16/15, 20138, Milan, Italy
| | - Marcello Ziaco
- BioSearch Srl., Villa Comunale c/o Stazione Zoologica "A. Dohrn", 80121, Naples, Italy
| | - Genoveffa Nuzzo
- Bio-Organic Chemistry Unit, Institute of Bio-Molecular Chemistry, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Italy
| | - Giuliana d'Ippolito
- Bio-Organic Chemistry Unit, Institute of Bio-Molecular Chemistry, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Italy
| | - Francesca Ferrera
- Department of Internal Medicine, University of Genova, Viale Benedetto XV 6, 16100, Genoa, Italy
| | - Paola Contini
- Department of Internal Medicine, University of Genova, Viale Benedetto XV 6, 16100, Genoa, Italy
| | - Daniela Castiglia
- Bio-Organic Chemistry Unit, Institute of Bio-Molecular Chemistry, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Italy
| | - Claudia Angelini
- Institute for Applied Mathematics "Mauro Picone", National Research Council, Via Pietro Castellino 111, 80131, Naples, Italy
| | - Raffaele De Palma
- Bio-Organic Chemistry Unit, Institute of Bio-Molecular Chemistry, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Italy.,Department of Internal Medicine, University of Genova, Viale Benedetto XV 6, 16100, Genoa, Italy
| | - Angelo Fontana
- Bio-Organic Chemistry Unit, Institute of Bio-Molecular Chemistry, National Research Council, Via Campi Flegrei 34, 80078, Pozzuoli, Italy. .,Department of Biology, University of Napoli "Federico II", Via Cupa Nuova Cinthia 21, 80126, Naples, Italy.
| |
Collapse
|
26
|
Zhao P, Xu Y, Jiang LL, Fan X, Ku Z, Li L, Liu X, Deng M, Arase H, Zhu JJ, Huang TY, Zhao Y, Zhang C, Xu H, Tong Q, Zhang N, An Z. LILRB2-mediated TREM2 signaling inhibition suppresses microglia functions. Mol Neurodegener 2022; 17:44. [PMID: 35717259 PMCID: PMC9206387 DOI: 10.1186/s13024-022-00550-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 06/08/2022] [Indexed: 12/18/2022] Open
Abstract
Background Microglia plays crucial roles in Alzheimer’s disease (AD) development. Triggering receptor expressed on myeloid cells 2 (TREM2) in association with DAP12 mediates signaling affecting microglia function. Here we study the negative regulation of TREM2 functions by leukocyte immunoglobulin-like receptor subfamily B member 2 (LILRB2), an inhibitory receptor bearing ITIM motifs. Methods To specifically interrogate LILRB2-ligand (oAβ and PS) interactions and microglia functions, we generated potent antagonistic LILRB2 antibodies with sub-nanomolar level activities. The biological effects of LILRB2 antagonist antibody (Ab29) were studied in human induced pluripotent stem cell (iPSC)–derived microglia (hMGLs) for migration, oAβ phagocytosis, and upregulation of inflammatory cytokines. Effects of the LILRB2 antagonist antibody on microglial responses to amyloid plaques were further studied in vivo using stereotaxic grafted microglia in 5XFAD mice. Results We confirmed the expression of both LILRB2 and TREM2 in human brain microglia using immunofluorescence. Upon co-ligation of the LILRB2 and TREM2 by shared ligands oAβ or PS, TREM2 signaling was significantly inhibited. We identified a monoclonal antibody (Ab29) that blocks LILRB2/ligand interactions and prevents TREM2 signaling inhibition mediated by LILRB2. Further, Ab29 enhanced microglia phagocytosis, TREM2 signaling, migration, and cytokine responses to the oAβ-lipoprotein complex in hMGL and microglia cell line HMC3. In vivo studies showed significantly enhanced clustering of microglia around plaques with a prominent increase in microglial amyloid plaque phagocytosis when 5XFAD mice were treated with Ab29. Conclusions This study revealed for the first time the molecular mechanisms of LILRB2-mediated inhibition of TREM2 signaling in microglia and demonstrated a novel approach of enhancing TREM2-mediated microglia functions by blocking LILRB2-ligand interactions. Translationally, a LILRB2 antagonist antibody completely rescued the inhibition of TREM2 signaling by LILRB2, suggesting a novel therapeutic strategy for improving microglial functions. Supplementary Information The online version contains supplementary material available at 10.1186/s13024-022-00550-y.
Collapse
Affiliation(s)
- Peng Zhao
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Yuanzhong Xu
- Center for Metabolic and Degenerative Diseases, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Lu-Lin Jiang
- Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Xuejun Fan
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Zhiqiang Ku
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Leike Li
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Xiaoye Liu
- Department of Physiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Mi Deng
- Department of Physiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Hisashi Arase
- Department of Immunochemistry, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Jay-Jiguang Zhu
- Department of Neurosurgery, University of Texas Health Science Center in Houston, McGovern Medical School and Memorial Hermann, Houston, TX, USA
| | - Timothy Y Huang
- Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Yingjun Zhao
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Chengcheng Zhang
- Department of Physiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Huaxi Xu
- State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Qingchun Tong
- Center for Metabolic and Degenerative Diseases, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Ningyan Zhang
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA.
| | - Zhiqiang An
- Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA.
| |
Collapse
|
27
|
Li RY, Qin Q, Yang HC, Wang YY, Mi YX, Yin YS, Wang M, Yu CJ, Tang Y. TREM2 in the pathogenesis of AD: a lipid metabolism regulator and potential metabolic therapeutic target. Mol Neurodegener 2022; 17:40. [PMID: 35658903 PMCID: PMC9166437 DOI: 10.1186/s13024-022-00542-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 05/09/2022] [Indexed: 12/13/2022] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) is a single-pass transmembrane immune receptor that is mainly expressed on microglia in the brain and macrophages in the periphery. Recent studies have identified TREM2 as a risk factor for Alzheimer’s disease (AD). Increasing evidence has shown that TREM2 can affect lipid metabolism both in the central nervous system (CNS) and in the periphery. In the CNS, TREM2 affects the metabolism of cholesterol, myelin, and phospholipids and promotes the transition of microglia into a disease-associated phenotype. In the periphery, TREM2 influences lipid metabolism by regulating the onset and progression of obesity and its complications, such as hypercholesterolemia, atherosclerosis, and nonalcoholic fatty liver disease. All these altered lipid metabolism processes could influence the pathogenesis of AD through several means, including affecting inflammation, insulin resistance, and AD pathologies. Herein, we will discuss a potential pathway that TREM2 mediates lipid metabolism to influence the pathogenesis of AD in both the CNS and periphery. Moreover, we discuss the possibility that TREM2 may be a key factor that links central and peripheral lipid metabolism under disease conditions, including AD. This link may be due to impacts on the integrity of the blood–brain barrier, and we introduce potential pathways by which TREM2 affects the blood–brain barrier. Moreover, we discuss the role of lipids in TREM2-associated treatments for AD. We propose some potential therapies targeting TREM2 and discuss the prospect and limitations of these therapies.
Collapse
Affiliation(s)
- Rui-Yang Li
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Qi Qin
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Han-Chen Yang
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Ying-Ying Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Ying-Xin Mi
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Yun-Si Yin
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Meng Wang
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Chao-Ji Yu
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Yi Tang
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China.
| |
Collapse
|
28
|
Ma WY, Wang SS, Wu QL, Zhou X, Chu SF, Chen NH. The versatile role of TREM2 in regulating of microglia fate in the ischemic stroke. Int Immunopharmacol 2022; 109:108733. [PMID: 35525233 DOI: 10.1016/j.intimp.2022.108733] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 03/07/2022] [Accepted: 03/22/2022] [Indexed: 12/15/2022]
Abstract
Microglia are the earliest activated and the longest lasting immune cells after stroke, and they participate in almost all the pathological reactions after stroke. However, their regulatory mechanism has not been fully elucidated. Triggering receptor expressed on myeloid cells-2 (TREM2) is a cell surface receptor that is mainly expressed in microglia of the central nervous system. The receptor plays an important role in regulating microglia energy metabolism and phenotypic transformation. At present, TREM2 has been developed as a potential target for AD, coronary atherosclerosis and other diseases. However, TREM2 does not provide a systematic summary of the functional transformation and intrinsic molecular mechanisms of microglia after stroke. In this paper, we have summarized the functional changes of TREM2 in microglia after stroke in recent years, and found that TREM2 has important effects on energy metabolism, phagocytosis and anti-inflammatory function of microglia after stroke, suggesting that TREM2 is a potential therapeutic target for the treatment of stroke.
Collapse
Affiliation(s)
- Wen-Yu Ma
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Sha-Sha Wang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Qing-Lin Wu
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Xin Zhou
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Shi-Feng Chu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Nai-Hong Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China; State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| |
Collapse
|
29
|
Jansen MI, Thomas Broome S, Castorina A. Exploring the Pro-Phagocytic and Anti-Inflammatory Functions of PACAP and VIP in Microglia: Implications for Multiple Sclerosis. Int J Mol Sci 2022; 23:ijms23094788. [PMID: 35563181 PMCID: PMC9104531 DOI: 10.3390/ijms23094788] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 02/04/2023] Open
Abstract
Multiple sclerosis (MS) is a chronic neuroinflammatory and demyelinating disease of the central nervous system (CNS), characterised by the infiltration of peripheral immune cells, multifocal white-matter lesions, and neurodegeneration. In recent years, microglia have emerged as key contributors to MS pathology, acting as scavengers of toxic myelin/cell debris and modulating the inflammatory microenvironment to promote myelin repair. In this review, we explore the role of two neuropeptides, pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP), as important regulators of microglial functioning during demyelination, myelin phagocytosis, and remyelination, emphasising the potential of these neuropeptides as therapeutic targets for the treatment of MS.
Collapse
|
30
|
Sasaguri H, Hashimoto S, Watamura N, Sato K, Takamura R, Nagata K, Tsubuki S, Ohshima T, Yoshiki A, Sato K, Kumita W, Sasaki E, Kitazume S, Nilsson P, Winblad B, Saito T, Iwata N, Saido TC. Recent Advances in the Modeling of Alzheimer's Disease. Front Neurosci 2022; 16:807473. [PMID: 35431779 PMCID: PMC9009508 DOI: 10.3389/fnins.2022.807473] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/22/2022] [Indexed: 12/13/2022] Open
Abstract
Since 1995, more than 100 transgenic (Tg) mouse models of Alzheimer's disease (AD) have been generated in which mutant amyloid precursor protein (APP) or APP/presenilin 1 (PS1) cDNA is overexpressed ( 1st generation models ). Although many of these models successfully recapitulate major pathological hallmarks of the disease such as amyloid β peptide (Aβ) deposition and neuroinflammation, they have suffered from artificial phenotypes in the form of overproduced or mislocalized APP/PS1 and their functional fragments, as well as calpastatin deficiency-induced early lethality, calpain activation, neuronal cell death without tau pathology, endoplasmic reticulum stresses, and inflammasome involvement. Such artifacts bring two important uncertainties into play, these being (1) why the artifacts arise, and (2) how they affect the interpretation of experimental results. In addition, destruction of endogenous gene loci in some Tg lines by transgenes has been reported. To overcome these concerns, single App knock-in mouse models harboring the Swedish and Beyreuther/Iberian mutations with or without the Arctic mutation (AppNL-G-F and AppNL-F mice) were developed ( 2nd generation models ). While these models are interesting given that they exhibit Aβ pathology, neuroinflammation, and cognitive impairment in an age-dependent manner, the model with the Artic mutation, which exhibits an extensive pathology as early as 6 months of age, is not suitable for investigating Aβ metabolism and clearance because the Aβ in this model is resistant to proteolytic degradation and is therefore prone to aggregation. Moreover, it cannot be used for preclinical immunotherapy studies owing to the discrete affinity it shows for anti-Aβ antibodies. The weakness of the latter model (without the Arctic mutation) is that the pathology may require up to 18 months before it becomes sufficiently apparent for experimental investigation. Nevertheless, this model was successfully applied to modulating Aβ pathology by genome editing, to revealing the differential roles of neprilysin and insulin-degrading enzyme in Aβ metabolism, and to identifying somatostatin receptor subtypes involved in Aβ degradation by neprilysin. In addition to discussing these issues, we also provide here a technical guide for the application of App knock-in mice to AD research. Subsequently, a new double knock-in line carrying the AppNL-F and Psen1 P117L/WT mutations was generated, the pathogenic effect of which was found to be synergistic. A characteristic of this 3rd generation model is that it exhibits more cored plaque pathology and neuroinflammation than the AppNL-G-F line, and thus is more suitable for preclinical studies of disease-modifying medications targeting Aβ. Furthermore, a derivative AppG-F line devoid of Swedish mutations which can be utilized for preclinical studies of β-secretase modifier(s) was recently created. In addition, we introduce a new model of cerebral amyloid angiopathy that may be useful for analyzing amyloid-related imaging abnormalities that can be caused by anti-Aβ immunotherapy. Use of the App knock-in mice also led to identification of the α-endosulfine-K ATP channel pathway as components of the somatostatin-evoked physiological mechanisms that reduce Aβ deposition via the activation of neprilysin. Such advances have provided new insights for the prevention and treatment of preclinical AD. Because tau pathology plays an essential role in AD pathogenesis, knock-in mice with human tau wherein the entire murine Mapt gene has been humanized were generated. Using these mice, the carboxy-terminal PDZ ligand of neuronal nitric oxide synthase (CAPON) was discovered as a mediator linking tau pathology to neurodegeneration and showed that tau humanization promoted pathological tau propagation. Finally, we describe and discuss the current status of mutant human tau knock-in mice and a non-human primate model of AD that we have successfully created.
Collapse
Affiliation(s)
- Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
| | - Shoko Hashimoto
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
| | - Naoto Watamura
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
| | - Kaori Sato
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku City, Japan
| | - Risa Takamura
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku City, Japan
| | - Kenichi Nagata
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Satoshi Tsubuki
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
| | - Toshio Ohshima
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku City, Japan
| | - Atsushi Yoshiki
- Experimental Animal Division, RIKEN BioResource Research Center, Tsukuba, Japan
| | - Kenya Sato
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
- Department of Marmoset Biology and Medicine, Central Institute for Experimental Animals, Kawasaki, Japan
| | - Wakako Kumita
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
- Department of Marmoset Biology and Medicine, Central Institute for Experimental Animals, Kawasaki, Japan
| | - Erika Sasaki
- Department of Marmoset Biology and Medicine, Central Institute for Experimental Animals, Kawasaki, Japan
- Laboratory for Marmoset Neural Architecture, RIKEN Center for Brain Science, Wako, Japan
| | - Shinobu Kitazume
- Department of Clinical Laboratory Sciences, School of Health Sciences, Fukushima Medical University, Fukushima, Japan
| | - Per Nilsson
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Bioclinicum, Karolinska Institutet, Stockholm, Sweden
| | - Bengt Winblad
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Bioclinicum, Karolinska Institutet, Stockholm, Sweden
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
- Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Nobuhisa Iwata
- Department of Genome-Based Drug Discovery and Leading Medical Research Core Unit, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Takaomi C. Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Japan
| |
Collapse
|
31
|
Abstract
In the past decade, substantial advances have been made in understanding the biology of tumour-associated macrophages (TAMs), and their clinical relevance is emerging. A particular aspect that is becoming increasingly clear is that the interaction of TAMs with cancer cells and stromal cells in the tumour microenvironment enables and sustains most of the hallmarks of cancer. Therefore, manipulation of TAMs could enable improved disease control in a substantial fraction of patients across a large number of cancer types. In this Review, we examine the diversity of TAMs in various cancer indications and how this heterogeneity is being revisited with the advent of single-cell technologies, and then explore the current knowledge on the functional roles of different TAM states and the prognostic and predictive value of TAM-related signatures. We also review agents targeting TAMs that are currently being or will soon be tested in clinical trials, and how manipulations of TAMs can improve existing anticancer treatments. Finally, we discuss how TAM-targeting approaches could be further integrated into routine clinical practice, considering a precision oncology approach and viewing TAMs as a dynamic population that can evolve under treatment pressure.
Collapse
|
32
|
Rodríguez AM, Rodríguez J, Giambartolomei GH. Microglia at the Crossroads of Pathogen-Induced Neuroinflammation. ASN Neuro 2022; 14:17590914221104566. [PMID: 35635133 PMCID: PMC9158411 DOI: 10.1177/17590914221104566] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Microglia are the resident tissue macrophages of the central nervous system (CNS). Recent findings point out that in the steady state the major role of microglia, is to instruct and regulate the correct function of the neuronal networks and different components of the neurovascular unit in the adult CNS, while providing immune surveillance. Paradoxically, during CNS infection immune activation of microglia generates an inflammatory milieu that contributes to the clearance of the pathogen but can, in the process, harm nearby cells of CNS. Most of the knowledge about the harmful effects of activated microglia on CNS has arisen from studies on neurodegenerative diseases. In this review we will focus on the beneficial role and detrimental functions of microglial cells on the neighboring cells of the CNS upon infection.
Collapse
Affiliation(s)
- Ana María Rodríguez
- Instituto de Inmunología, Genética y Metabolismo (INIGEM). CONICET. Facultad de Farmacia y Bioquímica, 28196Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Julia Rodríguez
- Instituto de Inmunología, Genética y Metabolismo (INIGEM). CONICET. Facultad de Farmacia y Bioquímica, 28196Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Guillermo Hernán Giambartolomei
- Instituto de Inmunología, Genética y Metabolismo (INIGEM). CONICET. Facultad de Farmacia y Bioquímica, 28196Universidad de Buenos Aires, Buenos Aires, Argentina
| |
Collapse
|
33
|
Soteros BM, Sia GM. Complement and microglia dependent synapse elimination in brain development. WIREs Mech Dis 2021; 14:e1545. [PMID: 34738335 PMCID: PMC9066608 DOI: 10.1002/wsbm.1545] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/10/2021] [Accepted: 10/12/2021] [Indexed: 01/31/2023]
Abstract
Synapse elimination, also known as synaptic pruning, is a critical step in the maturation of neural circuits during brain development. Mounting evidence indicates that the complement cascade of the innate immune system plays an important role in synapse elimination. Studies indicate that excess synapses during development are opsonized by complement proteins and subsequently phagocytosed by microglia which expresses complement receptors. The process is regulated by diverse molecular signals, including complement inhibitors that affect the activation of complement, as well as signals that affect microglial recruitment and activation. These signals may promote or inhibit the removal of specific sets of synapses during development. The complement-microglia system has also been implicated in the pathogenesis of several developmental brain disorders, suggesting that the dysregulation of mechanisms of synapse pruning may underlie the specific circuitry defects in these diseases. Here, we review the latest evidence on the molecular and cellular mechanisms of complement-dependent and microglia-dependent synapse elimination during brain development, and highlight the potential of this system as a therapeutic target for developmental brain disorders. This article is categorized under: Neurological Diseases > Molecular and Cellular Physiology Neurological Diseases > Stem Cells and Development Immune System Diseases > Molecular and Cellular Physiology.
Collapse
Affiliation(s)
- Breeanne M Soteros
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Gek Ming Sia
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| |
Collapse
|
34
|
Li T, Yu D, Oak HC, Zhu B, Wang L, Jiang X, Molday RS, Kriegstein A, Piao X. Phospholipid-flippase chaperone CDC50A is required for synapse maintenance by regulating phosphatidylserine exposure. EMBO J 2021; 40:e107915. [PMID: 34585770 PMCID: PMC8561630 DOI: 10.15252/embj.2021107915] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 08/25/2021] [Accepted: 09/01/2021] [Indexed: 12/13/2022] Open
Abstract
Synaptic refinement is a critical physiological process that removes excess synapses to establish and maintain functional neuronal circuits. Recent studies have shown that focal exposure of phosphatidylserine (PS) on synapses acts as an "eat me" signal to mediate synaptic pruning. However, the molecular mechanism underlying PS externalization at synapses remains elusive. Here, we find that murine CDC50A, a chaperone of phospholipid flippases, localizes to synapses, and that its expression depends on neuronal activity. Cdc50a knockdown leads to phosphatidylserine exposure at synapses and subsequent erroneous synapse removal by microglia partly via the GPR56 pathway. Taken together, our data support that CDC50A safeguards synapse maintenance by regulating focal phosphatidylserine exposure at synapses.
Collapse
Affiliation(s)
- Tao Li
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Diankun Yu
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Hayeon C Oak
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Beika Zhu
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Li Wang
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Department of NeurologyUniversity of California, San FranciscoSan FranciscoCAUSA
| | - Xueqiao Jiang
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| | - Robert S Molday
- Department of Biochemistry and Molecular BiologyUniversity of British ColumbiaVancouverBCCanada
| | - Arnold Kriegstein
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Department of NeurologyUniversity of California, San FranciscoSan FranciscoCAUSA
| | - Xianhua Piao
- Weill Institute for NeuroscienceUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Newborn Brain Research InstituteUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell ResearchUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
- Division of NeonatologyDepartment of PediatricsUniversity of California, San Francisco (UCSF)San FranciscoCAUSA
| |
Collapse
|
35
|
Mallach A, Gobom J, Arber C, Piers TM, Hardy J, Wray S, Zetterberg H, Pocock J. Differential Stimulation of Pluripotent Stem Cell-Derived Human Microglia Leads to Exosomal Proteomic Changes Affecting Neurons. Cells 2021; 10:cells10112866. [PMID: 34831089 PMCID: PMC8616378 DOI: 10.3390/cells10112866] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 10/07/2021] [Accepted: 10/13/2021] [Indexed: 01/22/2023] Open
Abstract
Microglial exosomes are an emerging communication pathway, implicated in fulfilling homeostatic microglial functions and transmitting neurodegenerative signals. Gene variants of triggering receptor expressed on myeloid cells-2 (TREM2) are associated with an increased risk of developing dementia. We investigated the influence of the TREM2 Alzheimer’s disease risk variant, R47Hhet, on the microglial exosomal proteome consisting of 3019 proteins secreted from human iPS-derived microglia (iPS-Mg). Exosomal protein content changed according to how the iPS-Mg were stimulated. Thus lipopolysaccharide (LPS) induced microglial exosomes to contain more inflammatory signals, whilst stimulation with the TREM2 ligand phosphatidylserine (PS+) increased metabolic signals within the microglial exosomes. We tested the effect of these exosomes on neurons and found that the exosomal protein changes were functionally relevant and influenced downstream functions in both neurons and microglia. Exosomes from R47Hhet iPS-Mg contained disease-associated microglial (DAM) signature proteins and were less able to promote the outgrowth of neuronal processes and increase mitochondrial metabolism in neurons compared with exosomes from the common TREM2 variant iPS-Mg. Taken together, these data highlight the importance of microglial exosomes in fulfilling microglial functions. Additionally, variations in the exosomal proteome influenced by the R47Hhet TREM2 variant may underlie the increased risk of Alzheimer’s disease associated with this variant.
Collapse
Affiliation(s)
- Anna Mallach
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College, London WC1N 1PJ, UK; (A.M.); (T.M.P.)
| | - Johan Gobom
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, S-43180 Molndal, Sweden; (J.G.); (H.Z.)
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80 Molndal, Sweden
| | - Charles Arber
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 1PJ, UK; (C.A.); (J.H.); (S.W.)
| | - Thomas M. Piers
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College, London WC1N 1PJ, UK; (A.M.); (T.M.P.)
| | - John Hardy
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 1PJ, UK; (C.A.); (J.H.); (S.W.)
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
| | - Selina Wray
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 1PJ, UK; (C.A.); (J.H.); (S.W.)
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, S-43180 Molndal, Sweden; (J.G.); (H.Z.)
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80 Molndal, Sweden
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London WC1N 1PJ, UK; (C.A.); (J.H.); (S.W.)
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
| | - Jennifer Pocock
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College, London WC1N 1PJ, UK; (A.M.); (T.M.P.)
- Correspondence:
| |
Collapse
|
36
|
Parkitny L, Maletic-Savatic M. Glial PAMPering and DAMPening of Adult Hippocampal Neurogenesis. Brain Sci 2021; 11:1299. [PMID: 34679362 PMCID: PMC8533961 DOI: 10.3390/brainsci11101299] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 09/16/2021] [Accepted: 09/22/2021] [Indexed: 12/24/2022] Open
Abstract
Adult neurogenesis represents a mature brain's capacity to integrate newly generated neurons into functional circuits. Impairment of neurogenesis contributes to the pathophysiology of various mood and cognitive disorders such as depression and Alzheimer's Disease. The hippocampal neurogenic niche hosts neural progenitors, glia, and vasculature, which all respond to intrinsic and environmental cues, helping determine their current state and ultimate fate. In this article we focus on the major immune communication pathways and mechanisms through which glial cells sense, interact with, and modulate the neurogenic niche. We pay particular attention to those related to the sensing of and response to innate immune danger signals. Receptors for danger signals were first discovered as a critical component of the innate immune system response to pathogens but are now also recognized to play a crucial role in modulating non-pathogenic sterile inflammation. In the neurogenic niche, viable, stressed, apoptotic, and dying cells can activate danger responses in neuroimmune cells, resulting in neuroprotection or neurotoxicity. Through these mechanisms glial cells can influence hippocampal stem cell fate, survival, neuronal maturation, and integration. Depending on the context, such responses may be appropriate and on-target, as in the case of learning-associated synaptic pruning, or excessive and off-target, as in neurodegenerative disorders.
Collapse
Affiliation(s)
- Luke Parkitny
- Baylor College of Medicine and Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital, Houston, TX 77030, USA;
| | | |
Collapse
|
37
|
Sato K, Watamura N, Fujioka R, Mihira N, Sekiguchi M, Nagata K, Ohshima T, Saito T, Saido TC, Sasaguri H. A third-generation mouse model of Alzheimer's disease shows early and increased cored plaque pathology composed of wild-type human amyloid β peptide. J Biol Chem 2021; 297:101004. [PMID: 34329683 PMCID: PMC8397900 DOI: 10.1016/j.jbc.2021.101004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/15/2021] [Accepted: 07/22/2021] [Indexed: 01/22/2023] Open
Abstract
We previously developed single App knock-in mouse models of Alzheimer's disease (AD) harboring the Swedish and Beyreuther/Iberian mutations with or without the Arctic mutation (AppNL-G-F and AppNL-F mice, respectively). These models showed Aβ pathology, neuroinflammation, and cognitive impairment in an age-dependent manner. The former model exhibits extensive pathology as early as 6 months, but is unsuitable for investigating Aβ metabolism and clearance because the Arctic mutation renders Aβ resistant to proteolytic degradation and prone to aggregation. In particular, it is inapplicable to preclinical immunotherapy studies due to its discrete affinity for anti-Aβ antibodies. The latter model may take as long as 18 months for the pathology to become prominent, which leaves an unfulfilled need for an Alzheimer's disease animal model that is both swift to show pathology and useful for antibody therapy. We thus utilized mutant Psen1 knock-in mice into which a pathogenic mutation (P117L) had been introduced to generate a new model that exhibits early deposition of wild-type human Aβ by crossbreeding the AppNL-F line with the Psen1P117L/WT line. We show that the effects of the pathogenic mutations in the App and Psen1 genes are additive or synergistic. This new third-generation mouse model showed more cored plaque pathology and neuroinflammation than AppNL-G-F mice and will help accelerate the development of disease-modifying therapies to treat preclinical AD.
Collapse
Affiliation(s)
- Kaori Sato
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan; Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku, Tokyo, Japan
| | - Naoto Watamura
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Ryo Fujioka
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Naomi Mihira
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Misaki Sekiguchi
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Kenichi Nagata
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
| | - Toshio Ohshima
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku, Tokyo, Japan
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan.
| | - Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan.
| |
Collapse
|
38
|
Cosker K, Mallach A, Limaye J, Piers TM, Staddon J, Neame SJ, Hardy J, Pocock JM. Microglial signalling pathway deficits associated with the patient derived R47H TREM2 variants linked to AD indicate inability to activate inflammasome. Sci Rep 2021; 11:13316. [PMID: 34172778 PMCID: PMC8233372 DOI: 10.1038/s41598-021-91207-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/20/2021] [Indexed: 02/05/2023] Open
Abstract
The R47H variant of the microglial membrane receptor TREM2 is linked to increased risk of late onset Alzheimer's disease. Human induced pluripotent stem cell derived microglia (iPS-Mg) from patient iPSC lines expressing the AD-linked R47Hhet TREM2 variant, common variant (Cv) or an R47Hhom CRISPR edited line and its isogeneic control, demonstrated that R47H-expressing iPS-Mg expressed a deficit in signal transduction in response to the TREM2 endogenous ligand phosphatidylserine with reduced pSYK-pERK1/2 signalling and a reduced NLRP3 inflammasome response, (including ASC speck formation, Caspase-1 activation and IL-1beta secretion). Apoptotic cell phagocytosis and soluble TREM2 shedding were unaltered, suggesting a disjoint between these pathways and the signalling cascades downstream of TREM2 in R47H-expressing iPS-Mg, whilst metabolic deficits in glycolytic capacity and maximum respiration were reversed when R47H expressing iPS-Mg were exposed to PS+ expressing cells. These findings suggest that R47H-expressing microglia are unable to respond fully to cell damage signals such as phosphatidylserine, which may contribute to the progression of neurodegeneration in late-onset AD.
Collapse
Affiliation(s)
- Katharina Cosker
- grid.83440.3b0000000121901201Department of Neuroinflammation, University College London, Queen Square Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ UK
| | - Anna Mallach
- grid.83440.3b0000000121901201Department of Neuroinflammation, University College London, Queen Square Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ UK
| | - Janhavi Limaye
- grid.83440.3b0000000121901201Department of Neuroinflammation, University College London, Queen Square Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ UK
| | - Thomas M. Piers
- grid.83440.3b0000000121901201Department of Neuroinflammation, University College London, Queen Square Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ UK
| | - James Staddon
- grid.428696.7Eisai Ltd, Mosquito Way, Hatfield, AL10 9SN UK
| | | | - John Hardy
- grid.436283.80000 0004 0612 2631Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London, WC1N 3BG UK ,grid.83440.3b0000000121901201Dementia Research Institute, University College, London, UCL, Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ UK ,grid.24515.370000 0004 1937 1450NIHR University College London Hospitals Biomedical Research Centre and Institute for Advanced Study, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Jennifer M. Pocock
- grid.83440.3b0000000121901201Department of Neuroinflammation, University College London, Queen Square Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ UK
| |
Collapse
|
39
|
Peruzzotti-Jametti L, Willis CM, Hamel R, Krzak G, Pluchino S. Metabolic Control of Smoldering Neuroinflammation. Front Immunol 2021; 12:705920. [PMID: 34249016 PMCID: PMC8262770 DOI: 10.3389/fimmu.2021.705920] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 05/31/2021] [Indexed: 12/11/2022] Open
Abstract
Compelling evidence exists that patients with chronic neurological conditions, which includes progressive multiple sclerosis, display pathological changes in neural metabolism and mitochondrial function. However, it is unknown if a similar degree of metabolic dysfunction occurs also in non-neural cells in the central nervous system. Specifically, it remains to be clarified (i) the full extent of metabolic changes in tissue-resident microglia and infiltrating macrophages after prolonged neuroinflammation (e.g., at the level of chronic active lesions), and (ii) whether these alterations underlie a unique pathogenic phenotype that is amenable for therapeutic targeting. Herein, we discuss how cell metabolism and mitochondrial function govern the function of chronic active microglia and macrophages brain infiltrates and identify new metabolic targets for therapeutic approaches aimed at reducing smoldering neuroinflammation.
Collapse
Affiliation(s)
- Luca Peruzzotti-Jametti
- Department of Clinical Neurosciences and National Institute for Health Research (NIHR) Biomedical Research Centre, University of Cambridge, Cambridge, United Kingdom
| | - Cory M Willis
- Department of Clinical Neurosciences and National Institute for Health Research (NIHR) Biomedical Research Centre, University of Cambridge, Cambridge, United Kingdom
| | - Regan Hamel
- Department of Clinical Neurosciences and National Institute for Health Research (NIHR) Biomedical Research Centre, University of Cambridge, Cambridge, United Kingdom
| | - Grzegorz Krzak
- Department of Clinical Neurosciences and National Institute for Health Research (NIHR) Biomedical Research Centre, University of Cambridge, Cambridge, United Kingdom
| | - Stefano Pluchino
- Department of Clinical Neurosciences and National Institute for Health Research (NIHR) Biomedical Research Centre, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
40
|
Zhou L, Matsushima GK. Tyro3, Axl, Mertk receptor-mediated efferocytosis and immune regulation in the tumor environment. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2021; 361:165-210. [PMID: 34074493 DOI: 10.1016/bs.ircmb.2021.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Three structurally related tyrosine receptor cell surface kinases, Tyro3, Axl, and Mertk (TAM) have been recognized to modulate immune function, tissue homeostasis, cardiovasculature, and cancer. The TAM receptor family appears to operate in adult mammals across multiple cell types, suggesting both widespread and specific regulation of cell functions and immune niches. TAM family members regulate tissue homeostasis by monitoring the presence of phosphatidylserine expressed on stressed or apoptotic cells. The detection of phosphatidylserine on apoptotic cells requires intermediary molecules that opsonize the dying cells and tether them to TAM receptors on phagocytes. This complex promotes the engulfment of apoptotic cells, also known as efferocytosis, that leads to the resolution of inflammation and tissue healing. The immune mechanisms dictating these processes appear to fall upon specific family members or may involve a complex of different receptors acting cooperatively to resolve and repair damaged tissues. Here, we focus on the role of TAM receptors in triggering efferocytosis and its consequences in the regulation of immune responses in the context of inflammation and cancer.
Collapse
Affiliation(s)
- Liwen Zhou
- UNC Neuroscience Center, University of North Carolina-CH, Chapel Hill, NC, United States
| | - Glenn K Matsushima
- UNC Neuroscience Center, University of North Carolina-CH, Chapel Hill, NC, United States; UNC Department of Microbiology & Immunology, University of North Carolina-CH, Chapel Hill, NC, United States; UNC Integrative Program for Biological & Genome Sciences, University of North Carolina-CH, Chapel Hill, NC, United States.
| |
Collapse
|
41
|
Magno L, Bunney TD, Mead E, Svensson F, Bictash MN. TREM2/PLCγ2 signalling in immune cells: function, structural insight, and potential therapeutic modulation. Mol Neurodegener 2021; 16:22. [PMID: 33823896 PMCID: PMC8022522 DOI: 10.1186/s13024-021-00436-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 02/24/2021] [Indexed: 01/21/2023] Open
Abstract
The central role of the resident innate immune cells of the brain (microglia) in neurodegeneration has become clear over the past few years largely through genome-wide association studies (GWAS), and has rapidly become an active area of research. However, a mechanistic understanding (gene to function) has lagged behind. That is now beginning to change, as exemplified by a number of recent exciting and important reports that provide insight into the function of two key gene products – TREM2 (Triggering Receptor Expressed On Myeloid Cells 2) and PLCγ2 (Phospholipase C gamma2) – in microglia, and their role in neurodegenerative disorders. In this review we explore and discuss these recent advances and the opportunities that they may provide for the development of new therapies.
Collapse
Affiliation(s)
- Lorenza Magno
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK.
| | - Tom D Bunney
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower Street, London, WC1E 6BT, UK
| | - Emma Mead
- Alzheimer's Research UK Oxford Drug Discovery Institute, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, OX3 7FZ, UK
| | - Fredrik Svensson
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK
| | - Magda N Bictash
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK
| |
Collapse
|
42
|
Sokolova D, Childs T, Hong S. Insight into the role of phosphatidylserine in complement-mediated synapse loss in Alzheimer's disease. Fac Rev 2021; 10:19. [PMID: 33718936 PMCID: PMC7946395 DOI: 10.12703/r/10-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The innate immune system plays an integral role in the brain. Synaptic pruning, a fundamental process in developmental circuit refinement, is partially mediated by neuroimmune signalling at the synapse. In particular, microglia, the major tissue-resident macrophages of the brain, and the classical complement cascade, an innate immune pathway that aids in the clearance of unwanted material, have been implicated in mediating synapse elimination. Emerging data suggest that improper signalling of the innate immune pathway at the synapse leads to pathological synapse loss in age-related neurodegenerative diseases, including Alzheimer's disease. Now the key questions are whether synapses are targeted by complement and, if so, which synapses are vulnerable to elimination. Here, we review recent work implicating C1q, the initiator of the classical complement cascade, and surrounding glia as mediators of synapse loss. We examine how synapses could undergo apoptosis-like pathways in the Alzheimer brain, which may lead to the externalisation of phosphatidylserine on synapses. Finally, we discuss potential roles for microglia and astrocytes in this 'synaptic apoptosis'. Critical insight into neuroimmune regulatory pathways on synapses will be key to developing effective targets against pathological synapse loss in dementia.
Collapse
Affiliation(s)
- Dimitra Sokolova
- UK Dementia Research Institute, Institute of Neurology, University College London, Gower Street, London WC1E 6BT, UK
| | - Thomas Childs
- UK Dementia Research Institute, Institute of Neurology, University College London, Gower Street, London WC1E 6BT, UK
| | - Soyon Hong
- UK Dementia Research Institute, Institute of Neurology, University College London, Gower Street, London WC1E 6BT, UK
| |
Collapse
|
43
|
Mallach A, Gobom J, Zetterberg H, Hardy J, Piers TM, Wray S, Pocock JM. The influence of the R47H triggering receptor expressed on myeloid cells 2 variant on microglial exosome profiles. Brain Commun 2021; 3:fcab009. [PMID: 34704019 PMCID: PMC8244649 DOI: 10.1093/braincomms/fcab009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 12/03/2020] [Accepted: 12/04/2020] [Indexed: 01/08/2023] Open
Abstract
Variants in the triggering receptor expressed on myeloid cells 2 gene are linked with an increased risk of dementia, in particular the R47Hhet triggering receptor expressed on myeloid cells 2 variant is linked to late-onset Alzheimer's disease. Using human induced pluripotent stem cells-derived microglia, we assessed whether variations in the dynamics of exosome secretion, including their components, from these cells might underlie some of this risk. We found exosome size was not altered between common variant controls and R47Hhet variants, but the amount and constitution of exosomes secreted were different. Exosome quantities were rescued by incubation with an ATP donor or with lipids via a phosphatidylserine triggering receptor expressed on myeloid cells 2 ligand. Following a lipopolysaccharide or phagocytic cell stimulus, exosomes from common variant and R47Hhet microglia were found to contain cytokines, chemokines, APOE and triggering receptor expressed on myeloid cells 2. Differences were observed in the expression of CCL22, IL-1β and triggering receptor expressed on myeloid cells 2 between common variant and R47Hhet derived exosomes. Furthermore unlike common variant-derived exosomes, R47Hhet exosomes contained additional proteins linked to negative regulation of transcription and metabolic processes. Subsequent addition of exosomes to stressed neurones showed R47Hhet-derived exosomes to be less protective. These data have ramifications for the responses of microglia in Alzheimer's disease and may point to further targets for therapeutic intervention.
Collapse
Affiliation(s)
- Anna Mallach
- Department of Neuroinflammation, Queen Square Institute of Neurology, University College London, London WC1N 1PJ, UK
| | - Johan Gobom
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, S-431 80, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80, Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, S-431 80, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, S-431 80, Mölndal, Sweden
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London WC1N 1PJ, UK
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- UK Dementia Research Institute University College London, London WC1E 6BT, UK
| | - John Hardy
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London WC1N 1PJ, UK
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- UK Dementia Research Institute University College London, London WC1E 6BT, UK
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London WC1N 1PJ, UK
- NIHR University College London Hospitals Biomedical Research Centre, London, UK
- Institute for Advanced Study, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Thomas M Piers
- Department of Neuroinflammation, Queen Square Institute of Neurology, University College London, London WC1N 1PJ, UK
| | - Selina Wray
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London WC1N 1PJ, UK
- Department of Neurodegenerative Disease, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Jennifer M Pocock
- Department of Neuroinflammation, Queen Square Institute of Neurology, University College London, London WC1N 1PJ, UK
| |
Collapse
|
44
|
Function of TREM1 and TREM2 in Liver-Related Diseases. Cells 2020; 9:cells9122626. [PMID: 33297569 PMCID: PMC7762355 DOI: 10.3390/cells9122626] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/01/2020] [Accepted: 12/03/2020] [Indexed: 02/07/2023] Open
Abstract
TREM1 and TREM2 are members of the triggering receptors expressed on myeloid cells (TREM) family. Both TREM1 and TREM2 are immunoglobulin superfamily receptors. Their main function is to identify foreign antigens and toxic substances, thereby adjusting the inflammatory response. In the liver, TREM1 and TREM2 are expressed on non-parenchymal cells, such as liver sinusoidal endothelial cells, Kupffer cells, and hepatic stellate cells, and cells which infiltrate the liver in response to injury including monocyte-derived macrophages and neutrophils. The function of TREM1 and TREM2 in inflammatory response depends on Toll-like receptor 4. TREM1 mainly augments inflammation during acute inflammation, while TREM2 mainly inhibits chronic inflammation to protect the liver from pathological changes. Chronic inflammation often induces metabolic abnormalities, fibrosis, and tumorigenesis. The above physiological changes lead to liver-related diseases, such as liver injury, nonalcoholic steatohepatitis, hepatic fibrosis, and hepatocellular carcinoma. Here, we review the function of TREM1 and TREM2 in different liver diseases based on inflammation, providing a more comprehensive perspective for the treatment of liver-related diseases.
Collapse
|
45
|
Hall-Roberts H, Agarwal D, Obst J, Smith TB, Monzón-Sandoval J, Di Daniel E, Webber C, James WS, Mead E, Davis JB, Cowley SA. TREM2 Alzheimer's variant R47H causes similar transcriptional dysregulation to knockout, yet only subtle functional phenotypes in human iPSC-derived macrophages. Alzheimers Res Ther 2020; 12:151. [PMID: 33198789 PMCID: PMC7667762 DOI: 10.1186/s13195-020-00709-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 10/20/2020] [Indexed: 01/21/2023]
Abstract
BACKGROUND TREM2 is a microglial cell surface receptor, with risk mutations linked to Alzheimer's disease (AD), including R47H. TREM2 signalling via SYK aids phagocytosis, chemotaxis, survival, and changes to microglial activation state. In AD mouse models, knockout (KO) of TREM2 impairs microglial clustering around amyloid and prevents microglial activation. The R47H mutation is proposed to reduce TREM2 ligand binding. We investigated cell phenotypes of the R47H mutant and TREM2 KO in a model of human microglia, and compared their transcriptional signatures, to determine the mechanism by which R47H TREM2 disrupts function. METHODS We generated human microglia-like iPSC-macrophages (pMac) from isogenic induced pluripotent stem cell (iPSC) lines, with homozygous R47H mutation or TREM2 knockout (KO). We firstly validated the effect of the R47H mutant on TREM2 surface and subcellular localization in pMac. To assess microglial phenotypic function, we measured phagocytosis of dead neurons, cell morphology, directed migration, survival, and LPS-induced inflammation. We performed bulk RNA-seq, comparing significant differentially expressed genes (DEGs; p < 0.05) between the R47H and KO versus WT, and bioinformatically predicted potential upstream regulators of TREM2-mediated gene expression. RESULTS R47H modified surface expression and shedding of TREM2, but did not impair TREM2-mediated signalling, or gross phenotypes that were dysregulated in the TREM2 KO (phagocytosis, motility, survival). However, altered gene expression in the R47H TREM2 pMac overlapped by 90% with the TREM2 KO and was characterised by dysregulation of genes involved with immunity, proliferation, activation, chemotaxis, and adhesion. Downregulated mediators of ECM adhesion included the vitronectin receptor αVβ3, and consequently, R47H TREM2 pMac adhered weakly to vitronectin compared with WT pMac. To counteract these transcriptional defects, we investigated TGFβ1, as a candidate upstream regulator. TGFβ1 failed to rescue vitronectin adhesion of pMac, although it improved αVβ3 expression. CONCLUSIONS The R47H mutation is not sufficient to cause gross phenotypic defects of human pMac under standard culture conditions. However, overlapping transcriptional defects with TREM2 KO supports the hypothesised partial loss-of-function effects of the R47H mutation. Furthermore, transcriptomics can guide us to more subtle phenotypic defects in the R47H cells, such as reduced cell adhesion, and can be used to predict targets for therapeutic intervention.
Collapse
Affiliation(s)
- Hazel Hall-Roberts
- James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE UK
- Nuffield Department of Medicine Research Building, Alzheimer’s Research UK Oxford Drug Discovery Institute, University of Oxford, Oxford, OX3 7FZ UK
| | - Devika Agarwal
- Nuffield Department of Medicine Research Building, Alzheimer’s Research UK Oxford Drug Discovery Institute, University of Oxford, Oxford, OX3 7FZ UK
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS UK
| | - Juliane Obst
- Nuffield Department of Medicine Research Building, Alzheimer’s Research UK Oxford Drug Discovery Institute, University of Oxford, Oxford, OX3 7FZ UK
| | - Thomas B. Smith
- Nuffield Department of Medicine Research Building, Alzheimer’s Research UK Oxford Drug Discovery Institute, University of Oxford, Oxford, OX3 7FZ UK
| | | | - Elena Di Daniel
- Nuffield Department of Medicine Research Building, Alzheimer’s Research UK Oxford Drug Discovery Institute, University of Oxford, Oxford, OX3 7FZ UK
| | - Caleb Webber
- UK Dementia Research Institute, Cardiff University, Cardiff, CF24 4HQ UK
| | - William S. James
- James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE UK
| | - Emma Mead
- Nuffield Department of Medicine Research Building, Alzheimer’s Research UK Oxford Drug Discovery Institute, University of Oxford, Oxford, OX3 7FZ UK
| | - John B. Davis
- Nuffield Department of Medicine Research Building, Alzheimer’s Research UK Oxford Drug Discovery Institute, University of Oxford, Oxford, OX3 7FZ UK
| | - Sally A. Cowley
- James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, Oxford, OX1 3RE UK
| |
Collapse
|
46
|
Cui X, Qiao J, Liu S, Wu M, Gu W. Mechanism of TREM2/DAP12 complex affecting β-amyloid plaque deposition in Alzheimer's disease modeled mice through mediating inflammatory response. Brain Res Bull 2020; 166:21-28. [PMID: 33053435 DOI: 10.1016/j.brainresbull.2020.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 09/01/2020] [Accepted: 10/05/2020] [Indexed: 01/07/2023]
Abstract
To investigate the mechanism of TREM2/DAP12 complex in mediating inflammatory responses that affect β-amyloid plaque deposition in Alzheimer's disease (AD) modeled mice. We measured escape latency and platform crossing time using the Morris water maze image automatic acquisition and software analysis system in TREM2 and DAP12 microglia knockout AD model mouse. We monitored the deposition of Aβ plaques in the mouse hippocampus using Congo red staining and measured levels. of inflammatory factors IL-6 and TNF-α by ELISA. Newborn mice with TREM2 knockout were selected for primary microglia isolation and culture, and Aged oligomer Aβ1-42 was added to the microglial culture medium to simulate the AD environment in vivo. Co-immunoprecipitation assay was used to detect the interaction between DAP12 and TREM2, and measured the inflammatory response induced by lipopolysaccharide (LPS) in mice with TREM2 and DAP12 knockdown through adeno-associated virus in BV2 microglia. The escape latency of the AD model mice with TREM2 and DAP12 knockout was higher and the number of crossing platforms lower than in the control group, whereas Aβ deposition and levels of inflammatory factors were higher. In TREM2 knockout microglial cultured with Aβ1-42, levels of IL-6 and TNF-α increased. Immunoprecipation pull-down assays showed that TREM2 binds to the membrane receptor DAP12 to form a complex. Knockout of TREM2 or DAP12 can inhibit LPS-induced microglial inflammatory responses. The TREM2/DAP12 complex inhibits the microglial inflammatory response through the JNK signaling pathway, thereby reducing the deposition of Aβ plaques and attenuation the behavioral manifestation in a mouse AD model.
Collapse
Affiliation(s)
- Xin Cui
- Yanjing Medical College of Capital Medical University, Beijing 101300, PR China
| | - Jun Qiao
- Department of Mental Health, The First Hospital of Hebei Medical University, Shijiazhuang 050031, PR China
| | - Sha Liu
- Department of Pharmacy, The Third Hospital of Shijiazhuang, Shijiazhuang 050011, PR China
| | - Ming Wu
- Department of Pharmacy, The Third Hospital of Shijiazhuang, Shijiazhuang 050011, PR China
| | - Weiwei Gu
- Experimental Center, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, PR China.
| |
Collapse
|
47
|
Kober DL, Stuchell-Brereton MD, Kluender CE, Dean HB, Strickland MR, Steinberg DF, Nelson SS, Baban B, Holtzman DM, Frieden C, Alexander-Brett J, Roberson ED, Song Y, Brett TJ. Functional insights from biophysical study of TREM2 interactions with apoE and Aβ 1-42. Alzheimers Dement 2020; 17:10.1002/alz.12194. [PMID: 33090700 PMCID: PMC8026773 DOI: 10.1002/alz.12194] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 08/12/2020] [Accepted: 08/20/2020] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Triggering receptor expressed on myeloid cells-2 (TREM2) is an immune receptor expressed on microglia that also can become soluble (sTREM2). How TREM2 engages different ligands remains poorly understood. METHODS We used comprehensive biolayer interferometry (BLI) analysis to investigate TREM2 and sTREM2 interactions with apolipoprotein E (apoE) and monomeric amyloid beta (Aβ) (mAβ42). RESULTS TREM2 engagement of apoE was protein mediated with little effect of lipidation, showing slight affinity differences between isoforms (E4 > E3 > E2). Another family member, TREML2, did not bind apoE. Disease-linked TREM2 variants within a "basic patch" minimally impact apoE binding. Instead, TREM2 uses a unique hydrophobic surface to bind apoE, which requires the apoE hinge region. TREM2 and sTREM2 directly bind mAβ42 and potently inhibit Aβ42 polymerization, suggesting a potential role for soluble sTREM2 in preventing AD pathogenesis. DISCUSSION These findings demonstrate that TREM2 has at least two ligand-binding surfaces that might be therapeutic targets and uncovers a potential function for sTREM2 in directly inhibiting Aβ polymerization.
Collapse
Affiliation(s)
- Daniel L. Kober
- Molecular Microbiology and Microbial Pathogenesis Program, Washington University School of Medicine, St. Louis, Missouri 63110
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Melissa D. Stuchell-Brereton
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Colin E. Kluender
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
- Biochemistry, Biophysics, and Structural Biology Program, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Hunter B. Dean
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer’s Disease Center, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, AL 35294
- Department of Biomedical Engineering, University of Alabama at Birmingham, AL 35294
| | - Michael R. Strickland
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Deborah F. Steinberg
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Samantha S. Nelson
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Berevan Baban
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - David M. Holtzman
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110
- Charles F. and Joanne Knight Alzheimer’s Disease Research Center, Washington University School of Medicine, St. Louis, Missouri 63110
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Carl Frieden
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Jennifer Alexander-Brett
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Erik D. Roberson
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer’s Disease Center, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, AL 35294
| | - Yuhua Song
- Department of Biomedical Engineering, University of Alabama at Birmingham, AL 35294
| | - Tom J. Brett
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri 63110
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110
| |
Collapse
|
48
|
Positron Emission Tomography in the Inflamed Cerebellum: Addressing Novel Targets among G Protein-Coupled Receptors and Immune Receptors. Pharmaceutics 2020; 12:pharmaceutics12100925. [PMID: 32998351 PMCID: PMC7601272 DOI: 10.3390/pharmaceutics12100925] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/17/2020] [Accepted: 09/25/2020] [Indexed: 01/12/2023] Open
Abstract
Inflammatory processes preceding clinical manifestation of brain diseases are moving increasingly into the focus of positron emission tomographic (PET) investigations. A key role in inflammation and as a target of PET imaging efforts is attributed to microglia. Cerebellar microglia, with a predominant ameboid and activated subtype, is of special interest also regarding improved and changing knowledge on functional involvement of the cerebellum in mental activities in addition to its regulatory role in motor function. The present contribution considers small molecule ligands as potential PET tools for the visualization of several receptors recognized to be overexpressed in microglia and which can potentially serve as indicators of inflammatory processes in the cerebellum. The sphingosine 1 phosphate receptor 1 (S1P1), neuropeptide Y receptor 2 (NPY2) and purinoceptor Y12 (P2Y12) cannabinoid receptors and the chemokine receptor CX3CR1 as G-protein-coupled receptors and the ionotropic purinoceptor P2X7 provide structures with rather classical binding behavior, while the immune receptor for advanced glycation end products (RAGE) and the triggering receptor expressed on myeloid cells 2 (TREM2) might depend for instance on further accessory proteins. Improvement in differentiation between microglial functional subtypes in comparison to the presently used 18 kDa translocator protein ligands as well as of the knowledge on the role of polymorphisms are special challenges in such developments.
Collapse
|
49
|
Abstract
Genetic studies of autosomal dominant Alzheimer's disease (AD) revealed that β-amyloid is central to disease pathogenesis. However, amyloid-targeted therapies have generally failed to slow progression in patients with symptomatic disease. This result suggests a transition from an early amyloid-dependent phase to a later amyloid-independent one, during which neurodegeneration occurs and symptoms arise. Microglia, the brain's resident myeloid cells, envelop amyloid and express the majority of genes linked to risk for sporadic late-onset AD. Their activation is associated spatially and temporally with the accumulation of pathological tau. Microglial facilitation of tau pathology may involve apolipoprotein E, the most important genetic risk factor for AD. Once formed, pathological tau spreads between connected neurons, eventually accumulating in the somatic compartment where catastrophic nuclear damage ensues. This emerging understanding of the postamyloid processes leading to neurodegeneration affords the opportunity to develop therapeutics that interrupt this pathological cascade and prevent or delay dementia, even after amyloid deposition.
Collapse
Affiliation(s)
- William J Ray
- The Neurodegeneration Consortium, Therapeutics Discovery Division, University of Texas MD Anderson Cancer Center, Houston, Texas 77154, USA; ,
| | - Virginie Buggia-Prevot
- The Neurodegeneration Consortium, Therapeutics Discovery Division, University of Texas MD Anderson Cancer Center, Houston, Texas 77154, USA; ,
| |
Collapse
|
50
|
Scott‐Hewitt N, Perrucci F, Morini R, Erreni M, Mahoney M, Witkowska A, Carey A, Faggiani E, Schuetz LT, Mason S, Tamborini M, Bizzotto M, Passoni L, Filipello F, Jahn R, Stevens B, Matteoli M. Local externalization of phosphatidylserine mediates developmental synaptic pruning by microglia. EMBO J 2020; 39:e105380. [PMID: 32657463 PMCID: PMC7429741 DOI: 10.15252/embj.2020105380] [Citation(s) in RCA: 205] [Impact Index Per Article: 51.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/05/2020] [Accepted: 06/15/2020] [Indexed: 12/21/2022] Open
Abstract
Neuronal circuit assembly requires the fine balance between synapse formation and elimination. Microglia, through the elimination of supernumerary synapses, have an established role in this process. While the microglial receptor TREM2 and the soluble complement proteins C1q and C3 are recognized as key players, the neuronal molecular components that specify synapses to be eliminated are still undefined. Here, we show that exposed phosphatidylserine (PS) represents a neuronal "eat-me" signal involved in microglial-mediated pruning. In hippocampal neuron and microglia co-cultures, synapse elimination can be partially prevented by blocking accessibility of exposed PS using Annexin V or through microglial loss of TREM2. In vivo, PS exposure at both hippocampal and retinogeniculate synapses and engulfment of PS-labeled material by microglia occurs during established developmental periods of microglial-mediated synapse elimination. Mice deficient in C1q, which fail to properly refine retinogeniculate connections, have elevated presynaptic PS exposure and reduced PS engulfment by microglia. These data provide mechanistic insight into microglial-mediated synapse pruning and identify a novel role of developmentally regulated neuronal PS exposure that is common among developing brain structures.
Collapse
Affiliation(s)
- Nicole Scott‐Hewitt
- F.M. Kirby Center for NeurobiologyBoston Children's HospitalBostonMAUSA
- Stanley Center for Psychiatric ResearchThe Broad Institute of MIT and HarvardCambridgeMAUSA
| | - Fabio Perrucci
- Laboratory of Pharmacology and Brain PathologyNeurocenterHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
- Department of Biomedical SciencesHumanitas UniversityPieve Emanuele (MI)Italy
| | - Raffaella Morini
- Laboratory of Pharmacology and Brain PathologyNeurocenterHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
| | - Marco Erreni
- Unit of Advanced Optical MicroscopyHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
| | - Matthew Mahoney
- F.M. Kirby Center for NeurobiologyBoston Children's HospitalBostonMAUSA
| | - Agata Witkowska
- Laboratory of NeurobiologyMax Planck Institute for Biophysical ChemistryGöttingenGermany
- Department of Molecular Pharmacology and Cell BiologyLeibniz‐Forschungsinstitut für Molekulare Pharmakologie (FMP)BerlinGermany
| | - Alanna Carey
- F.M. Kirby Center for NeurobiologyBoston Children's HospitalBostonMAUSA
| | - Elisa Faggiani
- Laboratory of Pharmacology and Brain PathologyNeurocenterHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
| | | | - Sydney Mason
- F.M. Kirby Center for NeurobiologyBoston Children's HospitalBostonMAUSA
| | - Matteo Tamborini
- Laboratory of Pharmacology and Brain PathologyNeurocenterHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
| | - Matteo Bizzotto
- Department of Biomedical SciencesHumanitas UniversityPieve Emanuele (MI)Italy
| | - Lorena Passoni
- Laboratory of Pharmacology and Brain PathologyNeurocenterHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
| | - Fabia Filipello
- Laboratory of Pharmacology and Brain PathologyNeurocenterHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
- Department of Biomedical SciencesHumanitas UniversityPieve Emanuele (MI)Italy
- Present address:
Department of NeurologyWashington UniversitySt. LouisMOUSA
| | - Reinhard Jahn
- Laboratory of NeurobiologyMax Planck Institute for Biophysical ChemistryGöttingenGermany
- University of GöttingenGöttingenGermany
| | - Beth Stevens
- F.M. Kirby Center for NeurobiologyBoston Children's HospitalBostonMAUSA
- Stanley Center for Psychiatric ResearchThe Broad Institute of MIT and HarvardCambridgeMAUSA
- Howard Hughes Medical InstituteBoston Children's HospitalBostonMAUSA
| | - Michela Matteoli
- Laboratory of Pharmacology and Brain PathologyNeurocenterHumanitas Clinical and Research Center ‐ IRCCSRozzano (MI)Italy
- CNR Institute of NeuroscienceMilanoItaly
| |
Collapse
|