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Wang Q, Cao Y, Ye S, Ding M, Ge W, Liang Y, Chen J. Trem2/Syk/PI3K axis contributes to the host protection against Toxoplasma gondii-induced adverse pregnancy outcomes via modulating decidual macrophages. PLoS Pathog 2024; 20:e1012543. [PMID: 39250507 PMCID: PMC11412541 DOI: 10.1371/journal.ppat.1012543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 09/19/2024] [Accepted: 08/28/2024] [Indexed: 09/11/2024] Open
Abstract
Decidual macrophages residing at the maternal-fetal interface have been recognized as pivotal factors for maintaining normal pregnancy; however, they are also key target cells of Toxoplasma gondii (T. gondii) in the pathology of T. gondii-induced adverse pregnancy. Trem2, as a functional receptor on macrophage surface, recognizes and binds various kinds of pathogens. The role and underlying mechanism of Trem2 in T. gondii infection remain elusive. In the present study, we found that T. gondii infection downregulated Trem2 expression and that Trem2-/- mice exhibited more severe adverse pregnancy outcomes than wildtype mice. We also demonstrated that T. gondii infection resulted in increased decidual macrophages, which were significantly reduced in the Trem2-/- pregnant mouse model as compared to wildtype control animals. We further described the inhibited proliferation, migration, and invasion functions of trophoblast cell by T. gondii antigens through macrophages as an "intermediate bridge", while this inhibition can be rescued by Trem2 agonist HSP60. Concurrently, Trem2 deficiency in bone marrow-derived macrophages (BMDMs) heightened the inhibitory effect of TgAg on the migration and invasion of trophoblast cells, accompanied by higher pro-inflammatory factors (IL-1β, IL-6 and TNF-α) but a lower chemokine (CXCL1) in T. gondii antigens-treated BMDMs. Furthermore, compelling evidence from animal models and in vitro cell experiments suggests that T. gondii inhibits the Trem2-Syk-PI3K signaling pathway, leading to impaired function of decidual macrophages. Therefore, our findings highlight Trem2 signaling as an essential pathway by which decidual macrophages respond to T. gondii infection, suggesting Trem2 as a crucial sensor of decidual macrophages and potential therapeutic target in the pathology of T. gondii-induced adverse pregnancy.
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Affiliation(s)
- Qing Wang
- Department of Pathogen Biology, School of Medicine, Nantong University, Nantong, Jiangsu, People’s Republic of China
| | - Yining Cao
- Department of Pathogen Biology, School of Medicine, Nantong University, Nantong, Jiangsu, People’s Republic of China
| | - Songyi Ye
- Department of Pediatric Surgery, Affiliated Hospital of Nantong University, Nantong, Jiangsu, People’s Republic of China
| | - Maoyuan Ding
- Department of Pathogen Biology, School of Medicine, Nantong University, Nantong, Jiangsu, People’s Republic of China
| | - Wenliang Ge
- Department of Pediatric Surgery, Affiliated Hospital of Nantong University, Nantong, Jiangsu, People’s Republic of China
| | - Yuejin Liang
- Department of Microbiology & Immunology, The University of Texas Medical Branch Galveston, Texas, United States of America
| | - Jinling Chen
- Department of Pathogen Biology, School of Medicine, Nantong University, Nantong, Jiangsu, People’s Republic of China
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Ukraintseva S, Yashkin AP, Akushevich I, Arbeev K, Duan H, Gorbunova G, Stallard E, Yashin A. Associations of infections and vaccines with Alzheimer's disease point to a role of compromised immunity rather than specific pathogen in AD. Exp Gerontol 2024; 190:112411. [PMID: 38548241 PMCID: PMC11060001 DOI: 10.1016/j.exger.2024.112411] [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: 02/19/2023] [Revised: 01/24/2024] [Accepted: 03/25/2024] [Indexed: 04/04/2024]
Abstract
INTRODUCTION Diverse pathogens (viral, bacterial, fungal) have been associated with Alzheimer's disease (AD) and related traits in various studies. This suggests that compromised immunity, rather than specific microbes, may play a role in AD by increasing an individual's vulnerability to various infections, which could contribute to neurodegeneration. If true, then vaccines that have heterologous effects on immunity, extending beyond protection against the targeted disease, may hold a potential for AD prevention. METHODS We evaluated the associations of common adult infections (herpes simplex, zoster (shingles), pneumonia, and recurrent mycoses), and vaccinations against shingles and pneumonia, with the risks of AD and other dementias in a pseudorandomized sample of the Health and Retirement Study (HRS). RESULTS Shingles, pneumonia and mycoses, diagnosed between ages 65 and 75, were all associated with significantly increased risk of AD later in life, by 16 %-42 %. Pneumococcal and shingles vaccines administered between ages 65-75 were both associated with a significantly lower risk of AD, by 15 %-21 %. These effects became less pronounced when AD was combined with other dementias. DISCUSSION Our findings suggest that both the pneumococcal polysaccharide vaccine and the live attenuated zoster vaccine can offer significant protection against AD. It remains to be determined if non-live shingles vaccine has a similar beneficial effect on AD. This study also found significant associations of various infections with the risk of AD, but not with the risks of other dementias. This indicates that vulnerability to infections may play a more significant role in AD than in other types of dementia, which warrants further investigation.
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Affiliation(s)
- Svetlana Ukraintseva
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA.
| | - Arseniy P Yashkin
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA.
| | - Igor Akushevich
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA
| | - Konstantin Arbeev
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA
| | - Hongzhe Duan
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA
| | - Galina Gorbunova
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA
| | - Eric Stallard
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA
| | - Anatoliy Yashin
- Biodemography of Aging Research Unit, Social Science Research Institute, Duke University, Durham, NC, USA
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Liang S, Xu L, Xin X, Zhang R, Wu Y. Study on pyroptosis-related genes Casp8, Gsdmd and Trem2 in mice with cerebral infarction. PeerJ 2024; 12:e16818. [PMID: 38348100 PMCID: PMC10860548 DOI: 10.7717/peerj.16818] [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: 09/08/2023] [Accepted: 12/30/2023] [Indexed: 02/15/2024] Open
Abstract
Objective Cerebral infarction is the main cause of death in patients with cerebrovascular diseases. Our research aimed to screen and validate pyroptosis-related genes in cerebral infarction for the targeted therapy of cerebral infarction. Methods and results A total of 1,517 differentially expressed genes (DEGs) were obtained by DESeq2 software analysis. Gene set enrichment analysis results indicated that genes of middle cerebral artery occlusion (MCAO) mice aged 3 months and 18 months were enriched in pyroptosis, respectively. Differentially expressed pyroptosis-related genes (including Aim2, Casp8, Gsdmd, Naip2, Naip5, Naip6 and Trem2) were obtained through intersection of DEGs and genes from pyroptosis Gene Ontology Term (GO:0070269), and they were up-regulated in the brain tissues of MCAO mice in GSE137482. In addition, Casp8, Gsdmd, and Trem2 were verified to be significantly up-regulated in MCAO mice in GSE93376. The evaluation of neurologic function and triphenyltetrazolium chloride staining showed that the MCAO mouse models were successfully constructed. Meanwhile, the expressions of TNF-α, pyroptosis-related proteins, Casp8, Gsdmd and Trem2 in MCAO mice were significantly up-regulated. We selected Trem2 for subsequent functional analysis. OGD treatment of BV2 cell in vitro significantly upregulated the expressions of Trem2. Subsequent downregulation of Trem2 expression in OGD-BV2 cells further increased the level of pyroptosis. Therefore, Trem2 is a protective factor regulating pyroptosis, thus influencing the progression of cerebral infarction. Conclusions Casp8, Gsdmd and Trem2 can regulate pyroptosis, thus affecting cerebral infarction.
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Affiliation(s)
- Shunli Liang
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- The Second Clinical Medical College of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Linsheng Xu
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Xilin Xin
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Rongbo Zhang
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - You Wu
- Department of Neurology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
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Wu Z, Yang S, Fang X, Shu Q, Chen Q. Function and mechanism of TREM2 in bacterial infection. PLoS Pathog 2024; 20:e1011895. [PMID: 38236825 PMCID: PMC10796033 DOI: 10.1371/journal.ppat.1011895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2024] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2), which is a lipid sensing and phagocytosis receptor, plays a key role in immunity and inflammation in response to pathogens. Here, we review the function and signaling of TREM2 in microbial binding, engulfment and removal, and describe TREM2-mediated inhibition of inflammation by negatively regulating the Toll-like receptor (TLR) response. We further illustrate the role of TREM2 in restoring organ homeostasis in sepsis and soluble TREM2 (sTREM2) as a diagnostic marker for sepsis-associated encephalopathy (SAE). Finally, we discuss the prospect of TREM2 as an interesting therapeutic target for sepsis.
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Affiliation(s)
- Zehua Wu
- Department of the Clinical Research Center, Children’s Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China
| | - Shiyue Yang
- Department of Anesthesiology, First Affiliated Hospital of Soochow University, Soochow, People’s Republic of China
| | - Xiangming Fang
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China
| | - Qiang Shu
- Department of the Clinical Research Center, Children’s Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China
- Key Laboratory of Diagnosis and Treatment of Neonatal Diseases of Zhejiang Province, Hangzhou, People’s Republic of China
| | - Qixing Chen
- Department of the Clinical Research Center, Children’s Hospital, National Clinical Research Center for Child Health, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China
- Key Laboratory of Diagnosis and Treatment of Neonatal Diseases of Zhejiang Province, Hangzhou, People’s Republic of China
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Peilin W, Ying P, Renyuan W, Zhuoxuan L, Zhenwu Y, Mai Z, Jianguo S, Hao Z, Gang Y, Lin L, Haodong L. Size-dependent gold nanoparticles induce macrophage M2 polarization and promote intracellular clearance of Staphylococcus aureus to alleviate tissue infection. Mater Today Bio 2023; 21:100700. [PMID: 37455821 PMCID: PMC10338365 DOI: 10.1016/j.mtbio.2023.100700] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 05/19/2023] [Accepted: 05/29/2023] [Indexed: 07/18/2023] Open
Abstract
Tissue infection typically results from blood transmission or the direct inoculation of bacteria following trauma. The pathogen-induced destruction of tissue prevents antibiotics from penetrating the infected site, and severe inflammation further impairs the efficacy of conventional treatment. The current study describes the size-dependent induction of macrophage polarization using gold nanoparticles. Gold nanoparticles with a diameter of 50 nm (Au50) can induce M2 polarization in macrophages by inhibiting the NF-κB signaling pathway and stimulate an inflammatory response in the environment by inhibiting the MAPK signaling pathway LPS. Furthermore, the induced polarization and anti-inflammatory effects of the Au50 nanoparticles promoted the osteogenic differentiation of BMSCs in vitro. In addition, the overexpression of TREM2 in macrophage induced by Au50 nanoparticles was found to promote macrophage phagocytosis of Staphylococcus aureus, enhance the fusion of autophagosomes and lysosomes, accelerate the intracellular degradation of S. aureus, in addition to achieving an effective local treatment of osteomyelitis and infectious skin defects in conjunction with inflammatory regulation and accelerating bone regeneration. The findings, therefore, demonstrate that Au50 nanoparticles can be utilized as a promising nanomaterial for in vivo treatment of infections.
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Affiliation(s)
- Wang Peilin
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Peng Ying
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Wang Renyuan
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Li Zhuoxuan
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Yang Zhenwu
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Zhao Mai
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Song Jianguo
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Zhang Hao
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Yin Gang
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Lin Lin
- School of Chemical and Environmental, Engineering, Shanghai Institute of Technology, Shanghai 201418, China
| | - Lin Haodong
- Trauma Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
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Španić Popovački E, Babić Leko M, Langer Horvat L, Brgić K, Vogrinc Ž, Boban M, Klepac N, Borovečki F, Šimić G. Soluble TREM2 Concentrations in the Cerebrospinal Fluid Correlate with the Severity of Neurofibrillary Degeneration, Cognitive Impairment, and Inflammasome Activation in Alzheimer's Disease. Neurol Int 2023; 15:842-856. [PMID: 37489359 PMCID: PMC10366813 DOI: 10.3390/neurolint15030053] [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: 05/22/2023] [Revised: 06/21/2023] [Accepted: 07/05/2023] [Indexed: 07/26/2023] Open
Abstract
BACKGROUND Individuals with specific TREM2 gene variants that encode for a Triggering Receptor Expressed on Myeloid cells 2 have a higher prevalence of Alzheimer's disease (AD). By interacting with amyloid and apolipoproteins, the TREM2 receptor regulates the number of myeloid cells, phagocytosis, and the inflammatory response. Higher TREM2 expression has been suggested to protect against AD. However, it is extremely difficult to comprehend TREM2 signaling in the context of AD. Previous results are variable and show distinct effects on diverse pathological changes in AD, differences between soluble and membrane isoform signaling, and inconsistency between animal models and humans. In addition, the relationship between TREM2 and inflammasome activation pathways is not yet entirely understood. OBJECTIVE This study aimed to determine the relationship between soluble TREM2 (sTREM2) levels in cerebrospinal fluid (CSF) and plasma samples and other indicators of AD pathology. METHODS Using the Enzyme-Linked Immunosorbent Assay (ELISA), we analyzed 98 samples of AD plasma, 35 samples of plasma from individuals with mild cognitive impairment (MCI), and 11 samples of plasma from healthy controls (HC), as well as 155 samples of AD CSF, 90 samples of MCI CSF, and 50 samples of HC CSF. RESULTS CSF sTREM2 levels were significantly correlated with neurofibrillary degeneration, cognitive decline, and inflammasome activity in AD patients. In contrast to plasma sTREM2, CSF sTREM2 levels in the AD group were higher than those in the MCI and HC groups. Moreover, concentrations of sTREM2 in CSF were substantially higher in the MCI group than in the HC group, indicating that CSF sTREM2 levels could be used not only to distinguish between HC and AD patients but also as a biomarker to detect earlier changes in the MCI stage. CONCLUSIONS The results indicate CSF sTREM2 levels reliably predict neurofibrillary degeneration, cognitive decline, and inflammasome activation, and also have a high diagnostic potential for distinguishing diseased from healthy individuals. To add sTREM2 to the list of required AD biomarkers, future studies will need to include a larger number of patients and utilize a standardized methodology.
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Affiliation(s)
- Ena Španić Popovački
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 12, 10000 Zagreb, Croatia
| | - Mirjana Babić Leko
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 12, 10000 Zagreb, Croatia
| | - Lea Langer Horvat
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 12, 10000 Zagreb, Croatia
| | - Klara Brgić
- Department of Neurosurgery, University Hospital Centre Zagreb, Kišpatićeva 12, 10000 Zagreb, Croatia
| | - Željka Vogrinc
- Laboratory for Neurobiochemistry, Department of Laboratory Diagnostics, University Hospital Centre Zagreb, Kišpatićeva 12, 10000 Zagreb, Croatia
| | - Marina Boban
- Department of Neurology, University Hospital Centre Zagreb, Kišpatićeva 12, 10000 Zagreb, Croatia
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Nataša Klepac
- Department of Neurology, University Hospital Centre Zagreb, Kišpatićeva 12, 10000 Zagreb, Croatia
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Fran Borovečki
- Department of Neurology, University Hospital Centre Zagreb, Kišpatićeva 12, 10000 Zagreb, Croatia
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Goran Šimić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 12, 10000 Zagreb, Croatia
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Guangzhang C, Fangfang F, Siqian D, Xinyi X, Xiaochuan B, Yihan R, Li W. Outer membrane vesicles from Escherichia coli are efficiently internalized by macrophage cells and alter their inflammatory response. Microb Pathog 2023; 175:105965. [PMID: 36592640 DOI: 10.1016/j.micpath.2022.105965] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/26/2022] [Accepted: 12/29/2022] [Indexed: 12/31/2022]
Abstract
The release of extracellular vesicles (EV) by pathogenic microbes is considered an alternative cell-to-cell transport of macromolecules transport mechanism. In Gram-negative bacteria, EVs may be formed by outer membrane budding, so-called outer membrane vesicles (OMVs). Previous studies have revealed E. coli constitutively release nano-sized OMVs, which can be potent activators of cellular functions without live bacteria. But the immunomodulatory activity of E. coli OMVs is still relatively poorly understood. Here we investigated the morphological characterization and composition of E.Coli OMVs, kinetics of internalization by Raw 264.7 macrophage cells, and their immunomodulatory activity on cells. By transmission electron microscopy and dynamic light scattering, E.Coli OMVs were identified as typical cup-shaped, bilayered membranous structures, mainly distributed between 72.5 and 212.5 nm. We also demonstrated by confocal fluorescence microscopy that exposure of Raw 264.7 cells to E.Coli OMVs resulted in internalization of these nanoparticles and decreased mitochondrial membrane potential. In addition, E. Coli OMVs treatment induced the production of ROS, iNOS, IL-1β, IL-6, IL-10 and up-regulation of CD86 and CD206. Taken together, our results indicated that E.Coli OMVs are immunobiologically active, can directly interact with macrophage and participate in immune responses.
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Affiliation(s)
- Chen Guangzhang
- School of Basic Medicine, Bengbu Medical College, Bengbu, 233030, China
| | - Fan Fangfang
- School of Basic Medicine, Bengbu Medical College, Bengbu, 233030, China
| | - Deng Siqian
- School of Basic Medicine, Bengbu Medical College, Bengbu, 233030, China
| | - Xia Xinyi
- School of Clinical Medicine, Bengbu Medical College, Bengbu, 233030, China
| | - Bian Xiaochuan
- School of Clinical Medicine, Bengbu Medical College, Bengbu, 233030, China
| | - Ren Yihan
- School of Clinical Medicine, Bengbu Medical College, Bengbu, 233030, China
| | - Wei Li
- School of Basic Medicine, Bengbu Medical College, Bengbu, 233030, China; Anhui Key Laboratory of Infection and Immunity at Bengbu Medical College, Bengbu, 233030, China.
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Abstract
Macrophage surface receptors are critical for pathogen defense, as they are the gatekeepers for pathogen entry and sensing, which trigger robust immune responses. TREM2 (triggering receptor expressed on myeloid cells 2) is a transmembrane surface receptor that mediates anti-inflammatory immune signaling. A recent study showed that TREM2 is a receptor for mycolic acids in the mycobacterial cell wall and inhibits macrophage activation. However, the underlying functional mechanism of how TREM2 regulates the macrophage antimycobacterial response remains unclear. Here, we show that Mycobacterium tuberculosis, the causative agent for tuberculosis, specifically binds to human TREM2 to disable the macrophage antibacterial response. Live but not killed mycobacteria specifically trigger the upregulation of TREM2 during macrophage infection through a mechanism dependent on STING (the stimulator of interferon genes). TREM2 facilitated uptake of M. tuberculosis into macrophages and is responsible for blocking the production of tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and reactive oxygen species (ROS), while enhancing the production of interferon-β (IFN-β) and IL-10. TREM2-mediated blockade of ROS production promoted the survival of M. tuberculosis within infected macrophages. Consistent with this, genetic deletion or antibody-mediated neutralization of TREM2 reduced the intracellular survival of M. tuberculosis through enhanced production of ROS. Importantly, inhibition of type I IFN signaling in TREM2-overexpressing macrophages restored the ability of these cells to produce inflammatory cytokines and ROS, resulting in normal levels of intracellular bacteria killing. Collectively, our study identifies TREM2 as an attractive host receptor for host-directed antimycobacterial therapeutics. IMPORTANCE Mycobacterium tuberculosis is one of the most ancient bacterial pathogens and remains the leading cause of death from a single bacterial agent. The success of M. tuberculosis relies greatly on its ability to parasitize and disable its host macrophages. Previous studies have found that M. tuberculosis uses its unique cell wall lipids to manipulate the immune response by binding to specific surface receptors on macrophages. Our study reveals that M. tuberculosis binds to TREM2, an immunomodulatory receptor expressed on macrophages, to facilitate a "silent" mode of entry. Increased levels of TREM2 triggered by intracellular sensing of M. tuberculosis promoted the intracellular survival of M. tuberculosis through type I IFN-driven inhibition of reactive oxygen species (ROS) and proinflammatory cytokine production. Importantly, deletion of TREM2 reversed the effects of "silent" entry and resulted in increased production of inflammatory cytokines, generation of ROS, and cell death. As such, antibody-mediated or pharmacological targeting of TREM2 could be a promising strategy for novel treatments against M. tuberculosis infection.
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Li XX, Zhang F. Targeting TREM2 for Parkinson's Disease: Where to Go? Front Immunol 2022; 12:795036. [PMID: 35003116 PMCID: PMC8740229 DOI: 10.3389/fimmu.2021.795036] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 12/13/2021] [Indexed: 12/16/2022] Open
Abstract
Parkinson’s disease (PD) is one of most common neurodegenerative disorders caused by a combination of environmental and genetic risk factors. Currently, numerous population genetic studies have shown that polymorphisms in myeloid cell-triggered receptor II (TREM2) are associated with a variety of neurodegenerative disorders. Recently, TREM2 has been verified to represent a promising candidate gene for PD susceptibility and progression. For example, the expression of TREM2 was apparently increased in the prefrontal cortex of PD patients. Moreover, the rare missense mutations in TREM2 (rs75932628, p.R47H) was confirmed to be a risk factor of PD. In addition, overexpression of TREM2 reduced dopaminergic neurodegeneration in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine mouse model of PD. Due to the complex pathogenesis of PD, there is still no effective drug treatment. Thus, TREM2 has received increasing widespread attention as a potential therapeutic target. This review focused on the variation of TREM2 in PD and roles of TREM2 in PD pathogenesis, such as excessive-immune inflammatory response, α-Synuclein aggregation and oxidative stress, to further provide evidence for new immune-related biomarkers and therapies for PD.
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Affiliation(s)
- Xiao-Xian Li
- Laboratory Animal Center and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, China
| | - Feng Zhang
- Laboratory Animal Center and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, China.,Joint International Research Laboratory of Ethnomedicine of Ministry of Education and Key Laboratory of Basic Pharmacology of Guizhou Province, Zunyi Medical University, Zunyi, China
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