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Tagé BSS, Gonzatti MB, Vieira RP, Keller AC, Bortoluci KR, Aimbire F. Three Main SCFAs Mitigate Lung Inflammation and Tissue Remodeling Nlrp3-Dependent in Murine HDM-Induced Neutrophilic Asthma. Inflammation 2024; 47:1386-1402. [PMID: 38329636 DOI: 10.1007/s10753-024-01983-x] [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: 11/07/2023] [Revised: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 02/09/2024]
Abstract
Neutrophilic asthma is generally defined by poorly controlled symptoms and high levels of neutrophils in the lungs. Short-chain fatty acids (SCFAs) are proposed as nonpharmacological therapy for allergic asthma, but their impact on the neutrophilic asthma lacks evidence. SCFAs regulate immune cell responses and impact the inflammasome NLRP3, a potential pharmacological target for neutrophilic asthma. Here, we explored the capacity of SCFAs to mitigate murine-induced neutrophilic asthma and the contribution of NLRP3 to this asthma. The objective of this study is to analyze whether SCFAs can attenuate lung inflammation and tissue remodeling in murine neutrophilic asthma and NLRP3 contribution to this endotype. Wild-type (WT) C57BL6 mice orotracheally received 10 μg of HDM (house dust mite) in 80 μL of saline on days 0, 6-10. To explore SCFAs, each HDM group received 200 mM acetate, propionate, or butyrate. To explore NLRP3, Nlrp3 KO mice received the same protocol of HDM. On the 14th day, after euthanasia, bronchoalveolar lavage fluid (BALF) and lungs were collected to evaluate cellularity, inflammatory cytokines, and tissue remodeling. HDM group had increased BALF neutrophil influx, TNF-α, IFN-γ, IL-17A, collagen deposition, and mucus secretion compared to control. SCFAs distinctively attenuate lung inflammation. Only features of tissue remodeling were Nlrp3-dependent such as collagen deposition, mucus secretion, active TGF-β cytokine, and IMs CD206+. SCFAs greatly decreased inflammatory cytokines and tissue remodeling. Only tissue remodeling was dependent on NLRP3. It reveals the potential of SCFAs to act as an additional therapy to mitigate neutrophilic asthma and the NLRP3 contribution to asthma.
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Affiliation(s)
- Barbara S S Tagé
- Department of Science and Technology, Federal University of São Paulo (UNIFESP), São José dos Campos, SP, 12247-014, Brazil.
| | - Michelangelo B Gonzatti
- Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo (UNIFESP), São Paulo, SP, 05468-901, Brazil
| | - Rodolfo P Vieira
- Postgraduate Program in Human Movement and Rehabilitation and in Pharmaceutical Sciences, Evangelical University of Goiás (UniEvangélica), Anápolis, GO, 75083-515, Brazil
- Postgraduate Program in Bioengineering, University Brasil, São Paulo, SP, 08230-030, Brazil
- Postgraduate Program in Sciences of Human Movement and Rehabilitation, Federal University of São Paulo (UNIFESP), Santos, SP, 11010-150, Brazil
| | - Alexandre C Keller
- Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo (UNIFESP), São Paulo, SP, 05468-901, Brazil
| | - Karina R Bortoluci
- Department of Pharmacology, Federal University of São Paulo (UNIFESP), São Paulo, SP, 04023-062, Brazil
| | - Flávio Aimbire
- Department of Science and Technology, Federal University of São Paulo (UNIFESP), São José dos Campos, SP, 12247-014, Brazil
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Boesze-Battaglia K, Cohen GH, Bates PF, Walker LM, Zekavat A, Shenker BJ. Cellugyrin (synaptogyrin-2) dependent pathways are used by bacterial cytolethal distending toxin and SARS-CoV-2 virus to gain cell entry. Front Cell Infect Microbiol 2024; 14:1334224. [PMID: 38698905 PMCID: PMC11063343 DOI: 10.3389/fcimb.2024.1334224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/19/2024] [Indexed: 05/05/2024] Open
Abstract
Aggregatibacter actinomycetemcomitans cytolethal distending toxin (Cdt) is capable of intoxicating lymphocytes macrophages, mast cells and epithelial cells. Following Cdt binding to cholesterol, in the region of membrane lipid rafts, the CdtB and CdtC subunits are internalized and traffic to intracellular compartments. These events are dependent upon, cellugyrin, a critical component of synaptic like microvesicles (SLMVCg+). Target cells, such as Jurkat cells, rendered unable to express cellugyrin are resistant to Cdt-induced toxicity. Similar to Cdt, SARS-CoV-2 entry into host cells is initiated by binding to cell surface receptors, ACE-2, also associated with cholesterol-rich lipid rafts; this association leads to fusion and/or endocytosis of viral and host cell membranes and intracellular trafficking. The similarity in internalization pathways for both Cdt and SARS-CoV-2 led us to consider the possibility that cellugyrin was a critical component in both processes. Cellugyrin deficient Calu-3 cells (Calu-3Cg-) were prepared using Lentiviral particles containing shRNA; these cells were resistant to infection by VSV/SARS-CoV-2-spike pseudotype virus and partially resistant to VSV/VSV-G pseudotype virus. Synthetic peptides representing various regions of the cellugyrin protein were prepared and assessed for their ability to bind to Cdt subunits using surface plasmon resonance. Cdt was capable of binding to a region designated the middle outer loop (MOL) which corresponds to a region extending into the cytoplasmic surface of the SLMVCg+. SARS-CoV-2 spike proteins were assessed for their ability to bind to cellugyrin peptides; SARS-CoV-2 full length spike protein preferentially binds to a region within the SLMVCg+ lumen, designated intraluminal loop 1A. SARS-CoV-2-spike protein domain S1, which contains the receptor binding domains, binds to cellugyrin N-terminus which extends out from the cytoplasmic surface of SLMV. Binding specificity was further analyzed using cellugyrin scrambled peptide mutants. We propose that SLMVCg+ represent a component of a common pathway that facilitates pathogen and/or pathogen-derived toxins to gain host cell entry.
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Affiliation(s)
- Kathleen Boesze-Battaglia
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Gary H. Cohen
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Paul F. Bates
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Lisa M. Walker
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ali Zekavat
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Bruce J. Shenker
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Intracellular lifestyle of Chlamydia trachomatis and host-pathogen interactions. Nat Rev Microbiol 2023:10.1038/s41579-023-00860-y. [PMID: 36788308 DOI: 10.1038/s41579-023-00860-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/23/2023] [Indexed: 02/16/2023]
Abstract
In recent years, substantial progress has been made in the understanding of the intracellular lifestyle of Chlamydia trachomatis and how the bacteria establish themselves in the human host. As an obligate intracellular pathogenic bacterium with a strongly reduced coding capacity, C. trachomatis depends on the provision of nutrients from the host cell. In this Review, we summarize the current understanding of how C. trachomatis establishes its intracellular replication niche, how its metabolism functions in the host cell, how it can defend itself against the cell autonomous and innate immune response and how it overcomes adverse situations through the transition to a persistent state. In particular, we focus on those processes for which a mechanistic understanding has been achieved.
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Formation and activity of NLRP3 inflammasome and histopathological changes in the lung of corpses with COVID-19. J Mol Histol 2022; 53:883-890. [PMID: 36100803 PMCID: PMC9470508 DOI: 10.1007/s10735-022-10101-w] [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: 12/11/2021] [Accepted: 09/02/2022] [Indexed: 12/03/2022]
Abstract
COVID-19 is a contagious disease that attacks many organs but the lungs are the main organs affected. The inflammasome activation results in the exacerbation of inflammatory response in infectious disease. The aim of this study is to investigate the formation and activity of the NLRP3 inflammasome complex and the histopathological changes caused by the coronavirus in the lung of deceased persons with COVID-19. In total, 10 corpses; 5 corpses with no history of any infectious diseases and COVID-19 and 5 corpses with the cause of death of COVID-19 were included in this study. Lung tissue samples were harvested during autopsy under safe conditions. Fresh tissues in each group were used to measure the genes expression and proteins level of NLRP3, ASC, Caspase-1, IL-1β, IL-6 and TNF-α and a routine hematoxylin and eosin staining was performed for histological assessment. Data are represented as the means ± SD. Statistical significance difference was accepted at a p-value less than 5%. The NLRP3, ASC, Caspase-1, IL-1β, IL-6 and TNF-α genes expression and proteins level were elevated in the lung of the COVID-19 group in comparison with the control group. Histological findings presented the increasing number of polymorphonuclear leukocytes, macrophages and also pulmonary fibrosis in the lungs of corpses with the cause of death of COVID-19. High expression of NLRP3 inflammasome components and its relation with the pathophysiology of the coronavirus-infected lung suggested that targeting the NLRP3 inflammasome could be helpful in achieving a more effective treatment in patients with COVID-19.
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Rotondo JC, Mazziotta C, Lanzillotti C, Stefani C, Badiale G, Campione G, Martini F, Tognon M. The Role of Purinergic P2X7 Receptor in Inflammation and Cancer: Novel Molecular Insights and Clinical Applications. Cancers (Basel) 2022; 14:1116. [PMID: 35267424 PMCID: PMC8909580 DOI: 10.3390/cancers14051116] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/09/2022] [Accepted: 02/17/2022] [Indexed: 12/11/2022] Open
Abstract
The purinergic P2X7 receptor (P2X7R) is a transmembrane protein whose expression has been related to a variety of cellular processes, while its dysregulation has been linked to inflammation and cancer. P2X7R is expressed in cancer and immune system cell surfaces. ATP plays a key role in numerous metabolic processes due to its abundance in the tumour microenvironment. P2X7R plays an important role in cancer by interacting with ATP. The unusual property of P2X7R is that stimulation with low doses of ATP causes the opening of a permeable channel for sodium, potassium, and calcium ions, whereas sustained stimulation with high doses of ATP favours the formation of a non-selective pore. The latter effect induces a change in intracellular homeostasis that leads to cell death. This evidence suggests that P2X7R has both pro- and anti-tumour proprieties. P2X7R is increasingly recognised as a regulator of inflammation. In this review, we aimed to describe the most relevant characteristics of P2X7R function, activation, and its ligands, while also summarising the role of P2X7R activation in the context of inflammation and cancer. The currently used therapeutic approaches and clinical trials of P2X7R modulators are also described.
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Affiliation(s)
- John Charles Rotondo
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
- Centre for Studies on Gender Medicine, Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy
| | - Chiara Mazziotta
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
- Centre for Studies on Gender Medicine, Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy
| | - Carmen Lanzillotti
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
- Centre for Studies on Gender Medicine, Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy
| | - Chiara Stefani
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
| | - Giada Badiale
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
| | - Giulia Campione
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
| | - Fernanda Martini
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
- Centre for Studies on Gender Medicine, Department of Medical Sciences, University of Ferrara, 44121 Ferrara, Italy
- Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, 44121 Ferrara, Italy
| | - Mauro Tognon
- Laboratories of Cell Biology and Molecular Genetics, Section of Experimental Medicine, Department of Medical Sciences, School of Medicine, University of Ferrara, 44121 Ferrara, Italy; (J.C.R.); (C.M.); (C.L.); (C.S.); (G.B.); (G.C.); (F.M.)
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Potential IFNγ Modulation of Inflammasome Pathway in Chlamydia trachomatis Infected Synovial Cells. Life (Basel) 2021; 11:life11121359. [PMID: 34947890 PMCID: PMC8707573 DOI: 10.3390/life11121359] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/02/2021] [Accepted: 12/04/2021] [Indexed: 01/15/2023] Open
Abstract
Following a Chlamydia trachomatis infection, the host immune response is characterized by its recognition via Toll-like and Nod-like Receptors, and the subsequent activation of interferon (IFN)-γ-mediated signaling pathways. Recently, the inflammasome-mediated host cell response has emerged to play a role in the physiopathology of C. trachomatis infection. Here we investigated, for the first time, the interaction of IFN-γ and inflammasome in an in vitro model of C. trachomatis-infected primary human synovial cells. Chlamydial replication as well as the expression of caspase-1, IL-1β, as well as IL-18 and IL-6, were assayed. Our results demonstrated the inhibitory activity of IFN-γ by interfering with the inflammasome network through the downregulation of caspase-1 mRNA expression. In addition, the ability of C. trachomatis to hinder the inflammasome pathway favoring its intracellular survival within synovial cells, was observed. Overall, our data suggest a potential mechanism of immune evasion by C. trachomatis in synovial cells, that may be contested by IFN-γ.
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Sixt BS. Host cell death during infection with Chlamydia: a double-edged sword. FEMS Microbiol Rev 2021; 45:5902849. [PMID: 32897321 PMCID: PMC7794043 DOI: 10.1093/femsre/fuaa043] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/02/2020] [Indexed: 12/12/2022] Open
Abstract
The phylum Chlamydiae constitutes a group of obligate intracellular bacteria that infect a remarkably diverse range of host species. Some representatives are significant pathogens of clinical or veterinary importance. For instance, Chlamydia trachomatis is the leading infectious cause of blindness and the most common bacterial agent of sexually transmitted diseases. Chlamydiae are exceptionally dependent on their eukaryotic host cells as a consequence of their developmental biology. At the same time, host cell death is an integral part of the chlamydial infection cycle. It is therefore not surprising that the bacteria have evolved exquisite and versatile strategies to modulate host cell survival and death programs to their advantage. The recent introduction of tools for genetic modification of Chlamydia spp., in combination with our increasing awareness of the complexity of regulated cell death in eukaryotic cells, and in particular of its connections to cell-intrinsic immunity, has revived the interest in this virulence trait. However, recent advances also challenged long-standing assumptions and highlighted major knowledge gaps. This review summarizes current knowledge in the field and discusses possible directions for future research, which could lead us to a deeper understanding of Chlamydia's virulence strategies and may even inspire novel therapeutic approaches.
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Affiliation(s)
- Barbara S Sixt
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden
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Chlamydia Uses K + Electrical Signalling to Orchestrate Host Sensing, Inter-Bacterial Communication and Differentiation. Microorganisms 2021; 9:microorganisms9010173. [PMID: 33467438 PMCID: PMC7830353 DOI: 10.3390/microorganisms9010173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/08/2021] [Accepted: 01/08/2021] [Indexed: 12/30/2022] Open
Abstract
Prokaryotic communities coordinate quorum behaviour in response to external stimuli to control fundamental processes including inter-bacterial communication. The obligate intracellular bacterial pathogen Chlamydia adopts two developmental forms, invasive elementary bodies (EBs) and replicative reticulate bodies (RBs), which reside within a specialised membrane-bound compartment within the host cell termed an inclusion. The mechanisms by which this bacterial community orchestrates different stages of development from within the inclusion in coordination with the host remain elusive. Both prokaryotic and eukaryotic kingdoms exploit ion-based electrical signalling for fast intercellular communication. Here we demonstrate that RBs specifically accumulate potassium (K+) ions, generating a gradient. Disruption of this gradient using ionophores or an ion-channel inhibitor stalls the Chlamydia lifecycle, inducing persistence. Using photobleaching approaches, we establish that the RB is the master regulator of this [K+] differential and observe a fast K+ exchange between RBs revealing a role for this ion in inter-bacterial communication. Finally, we demonstrate spatio-temporal regulation of bacterial membrane potential during RB to EB differentiation within the inclusion. Together, our data reveal that Chlamydia harnesses K+ to orchestrate host sensing, inter-bacteria communication and pathogen differentiation.
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Coutinho-Silva R, Savio LEB. Purinergic signalling in host innate immune defence against intracellular pathogens. Biochem Pharmacol 2021; 187:114405. [PMID: 33406411 DOI: 10.1016/j.bcp.2021.114405] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/29/2020] [Accepted: 12/31/2020] [Indexed: 02/07/2023]
Abstract
Purinergic signalling is an evolutionarily conserved signalling pathway mediated by extracellular nucleotides and nucleosides. Tri- and diphosphonucleotides released from host cells during intracellular pathogen infections activate plasma membrane purinergic type 2 receptors (P2 receptors) that stimulate microbicidal mechanisms in host innate immune cells. P2X ion channels and P2Y G protein-coupled receptors are involved in activating host innate immune defence mechanisms, phagocytosis, phagolysosomal fusion, production of reactive species, acidification of parasitophorous vacuoles, inflammasome activation, and the release of cytokines, chemokines, and other inflammatory mediators. In this review, as part of a special issue in tribute to Geoffrey Burnstock, we discuss advances in understanding the importance of P2 receptors in the host antimicrobial innate mechanisms against intracellular pathogen infections.
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Affiliation(s)
- Robson Coutinho-Silva
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Luiz Eduardo Baggio Savio
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
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Balin BJ, Hudson AP. Perspectives on the Intracellular Bacterium Chlamydia pneumoniae in Late-Onset Dementia. CURRENT CLINICAL MICROBIOLOGY REPORTS 2020. [DOI: 10.1007/s40588-020-00146-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Abstract
Purpose of Review
Chronic diseases remain a daunting challenge for clinicians and researchers alike. While difficult to completely understand, most chronic diseases, including late-onset dementias, are thought to arise as an interplay between host genetic factors and environmental insults. One of the most diverse and ubiquitous environmental insults centers on infectious agents. Associations of infectious agents with late-onset dementia have taken on heightened importance, including our investigations of infection by the intracellular respiratory bacterium, Chlamydia pneumoniae (Cpn), in late-onset dementia of the Alzheimer’s type.
Recent Findings
Over the last two decades, the relationship of this infection to pathogenesis in late-onset dementia has become much clearer. This clarity has resulted from applying contemporary molecular genetic, biochemical, immunochemical, and cell culture techniques to analysis of human brains, animal models, and relevant in vitro cell culture systems. Data from these studies, taken in aggregate form, now can be applied to evaluation of proof of concept for causation of this infection with late-onset disease. In this evaluation, modifications to the original Koch postulates can be useful for elucidating causation.
Summary
All such relevant studies are outlined and summarized in this review, and they demonstrate the utility of applying modified Koch postulates to the etiology of late-onset dementia of the Alzheimer’s type. Regardless, it is clear that even with strong observational evidence, in combination with application of modifications of Koch’s postulates, we will not be able to conclusively state that Cpn infection is causative for disease pathogenesis in late-onset dementia. Moreover, this conclusion obtains as well for the putative causation of this condition by other pathogens, including herpes simplex virus type 1, Borrelia burgdorferi, and Porphyromonas gingivalis.
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Boesze-Battaglia K, Dhingra A, Walker LM, Zekavat A, Shenker BJ. Internalization and Intoxication of Human Macrophages by the Active Subunit of the Aggregatibacter actinomycetemcomitans Cytolethal Distending Toxin Is Dependent Upon Cellugyrin (Synaptogyrin-2). Front Immunol 2020; 11:1262. [PMID: 32655562 PMCID: PMC7325893 DOI: 10.3389/fimmu.2020.01262] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 05/18/2020] [Indexed: 12/20/2022] Open
Abstract
The Aggregatibacter actinomycetemcomitans cytolethal distending toxin (Cdt) is a heterotrimeric AB2 toxin capable of inducing cell cycle arrest and apoptosis in lymphocytes and other cell types. Recently, we have demonstrated that human macrophages are resistant to Cdt-induced apoptosis but are susceptible to toxin-induced pro-inflammatory cytokine response involving activation of the NLRP3 inflammasome. Exposure to Cdt results in binding to the cell surface followed by internalization and translocation of the active subunit, CdtB, to intracellular compartments. Internalization involves hijacking of retrograde pathways; treatment of cells with Retro-2 leads to a decrease in CdtB-Golgi association. These events are dependent upon toxin binding to cholesterol in the context of lipid rich membrane microdomains often referred to as lipid rafts. We now demonstrate that within 1 h of exposure of macrophages to Cdt, CdtB is internalized and found primarily within lipid rafts; concurrently, cellugyrin (synaptogyrin-2) also translocates into lipid rafts. Further analysis by immunoprecipitation indicates that CdtB associates with complexes containing both cellugyrin and Derlin-2. Moreover, a human macrophage cell line deficient in cellugyrin expression (THP-1Cg-) challenged with Cdt failed to internalize CdtB and was resistant to the Cdt-induced pro-inflammatory response. We propose that lipid rafts along with cellugyrin play a critical role in the internalization and translocation of CdtB to critical intracellular target sites in human macrophages. These studies provide the first evidence that cellugyrin is expressed in human macrophages and plays a critical role in Cdt toxicity of these cells.
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Affiliation(s)
- Kathleen Boesze-Battaglia
- Department of Biochemistry, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, United States
| | - Anuradha Dhingra
- Department of Biochemistry, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, United States
| | - Lisa M Walker
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, United States
| | - Ali Zekavat
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, United States
| | - Bruce J Shenker
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, United States
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Al-Kuhlani M, Lambert G, Pal S, de la Maza L, Ojcius DM. Immune response against Chlamydia trachomatis via toll-like receptors is negatively regulated by SIGIRR. PLoS One 2020; 15:e0230718. [PMID: 32210474 PMCID: PMC7094862 DOI: 10.1371/journal.pone.0230718] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 03/06/2020] [Indexed: 12/18/2022] Open
Abstract
Chlamydia trachomatis is the most common bacterial sexually-transmitted infection and the major cause of preventable blindness worldwide. The asymptomatic nature of many infections along with uncontrolled inflammation leads to irreversible damage in the upper genital tract and the tarsal conjunctivae, with the major complications of infertility and chronic pelvic pain, and blindness, respectively. Inflammation must, therefore, be tightly regulated to avoid an unrestrained immune response. The genetic factors that regulate inflammation through Toll-like receptor (TLR) signaling pathways during C. trachomatis infection have not been fully characterized. SIGIRR (also known as IL-1R8 or TIR8) can regulate inflammation in response to various pathogens and diseases. However, nothing is known about its role during C. trachomatis infection. Expression of the pro-inflammatory chemokine, IL-8, was measured in epithelial cells infected with C. trachomatis. The effect of SIGIRR was determined by depleting SIGIRR or over-expressing SIGIRR in the epithelial cells before infection. Our results indicate that, in the absence of SIGIRR, epithelial cells induce higher levels of the pro-inflammatory chemokine, IL-8, in response to C. trachomatis infection. In addition, SIGIRR associates with MyD88 in both infected and uninfected infected cells. Collectively, our data demonstrate that SIGIRR functions as a negative regulator of the immune response to C. trachomatis infection. This finding provides insights into the immuno-pathogenesis of C. trachomatis that can be used to treat and identify individuals at risk of uncontrolled inflammation during infection.
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Affiliation(s)
- Mufadhal Al-Kuhlani
- Life Science Department, Fresno City College, Fresno, CA, United States of America
- Department of Biomedical Sciences, Arthur Dugoni School of Dentistry, University of the Pacific, San Francisco, CA, United States of America
| | - Graham Lambert
- College of Osteopathic Medicine, Touro University Nevada, Henderson, NV, United States of America
| | - Sukumar Pal
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA, United States of America
| | - Luis de la Maza
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA, United States of America
| | - David M. Ojcius
- Department of Biomedical Sciences, Arthur Dugoni School of Dentistry, University of the Pacific, San Francisco, CA, United States of America
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Shenker BJ, Walker LM, Zekavat Z, Ojcius DM, Huang PR, Boesze-Battaglia K. Cytolethal distending toxin-induced release of interleukin-1β by human macrophages is dependent upon activation of glycogen synthase kinase 3β, spleen tyrosine kinase (Syk) and the noncanonical inflammasome. Cell Microbiol 2020; 22:e13194. [PMID: 32068949 DOI: 10.1111/cmi.13194] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 01/09/2020] [Accepted: 01/24/2020] [Indexed: 12/19/2022]
Abstract
Cytolethal distending toxins (Cdt) are a family of toxins produced by several human pathogens which infect mucocutaneous tissue and induce inflammatory disease. We have previously demonstrated that the Aggregatibacter actinomycetemcomitans Cdt induces a pro-inflammatory response from human macrophages which involves activation of the NLRP3 inflammasome. We now demonstrate that in addition to activating caspase-1 (canonical inflammasome), Cdt treatment leads to caspase-4 activation and involvement of the noncanonical inflammasome. Cdt-treated cells exhibit pyroptosis characterised by cleavage of gasdermin-D (GSDMD), release of HMGB1 at 24 hr and LDH at 48 hr. Inhibition of either the canonical (caspase-1) or noncanonical (caspase-4) inflammasome blocks both Cdt-induced release of IL-1β and induction of pyroptosis. Analysis of upstream events indicates that Cdt induces Syk phosphorylation (activation); furthermore, blockade of Syk expression and inhibition of pSyk activity inhibit both Cdt-induced cytokine release and pyroptosis. Finally, we demonstrate that increases in pSyk are dependent upon Cdt-induced activation of GSK3β. These studies advance our understanding of Cdt function and provide new insight into the virulence potential of Cdt in mediating the pathogenesis of disease caused by Cdt-producing organisms such as A. actinomycetemcomitans.
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Affiliation(s)
- Bruce J Shenker
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania, USA
| | - Lisa M Walker
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania, USA
| | - Zeyed Zekavat
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania, USA
| | - David M Ojcius
- Department of Biomedical Sciences, University of the Pacific Arthur A. Dugoni School of Dentistry, San Francisco, California, USA
| | - Pei-Rong Huang
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan
| | - Kathleen Boesze-Battaglia
- Department of Biochemistry, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania, USA
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14
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Kortesoja M, Trofin RE, Hanski L. A platform for studying the transfer of Chlamydia pneumoniae infection between respiratory epithelium and phagocytes. J Microbiol Methods 2020; 171:105857. [PMID: 32006529 DOI: 10.1016/j.mimet.2020.105857] [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: 11/26/2019] [Revised: 01/13/2020] [Accepted: 01/28/2020] [Indexed: 12/17/2022]
Abstract
The obligate intracellular bacterium, Chlamydia pneumoniae, has been identified as a risk factor for several chronic inflammatory diseases in addition to respiratory tract infections. The dissemination of C. pneumoniae from respiratory tract to secondary sites of infection occurs via infected monocyte / macrophage line cells, in which C. pneumoniae can persist as an antibiotic-refractory phenotype. To allow more detailed studies on the epithelium-monocyte/macrophage transition of the infection, new in vitro bioassays are needed. To this end, a coculture system with human continuous cell lines was established. Respiratory epithelial HL cells were infected with C. pneumoniae and THP-1 monocytes were added into the cultures at 67 h post infection. After a 5 h coculture, THP-1 cells were collected with a biotinylated HLA antibody and streptavidin-coated magnetic beads and C. pneumoniae genome copy numbers in THP-1 determined by quantitative PCR. The assay was optimized for cell densities, incubation time, THP-1 separation technique and buffer composition, and its robustness was demonstrated by a Z' value of 0.6. The mitogen-activated protein kinase (MAPK) inhibitors: SP600125 (JNK inhibitor), SB203580 (p38 inhibitor) and FR180204 (ERK inhibitor) suppressed the transfer of C. pneumoniae from HL to THP-1 cells, making them suitable positive controls for the assay. Based on analysis of separate steps of the process, the MAPK inhibitors suppress the bacterial entry to THP-1 cells. The transfer of C. pneumoniae from epithelium to phagocytes represents a crucial step in the establishment of persistent infections by this pathogen, and the presented methods enables future studies to block this process by therapeutic means.
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Affiliation(s)
- Maarit Kortesoja
- Drug Research Program, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014, Finland
| | - Raluca Elena Trofin
- Drug Research Program, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014, Finland; Faculty of Pharmacy, University of Bucharest, Bulevardul Regina Elisabeta 4-12, 030018 Bucharest, Romania
| | - Leena Hanski
- Drug Research Program, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014, Finland.
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15
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Caspase-11 Contributes to Oviduct Pathology during Genital Chlamydia Infection in Mice. Infect Immun 2019; 87:IAI.00262-19. [PMID: 31160363 DOI: 10.1128/iai.00262-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/24/2019] [Indexed: 11/20/2022] Open
Abstract
It has been shown that caspase-1, but not its upstream activator, ASC, contributes to oviduct pathology during mouse genital Chlamydia muridarum infection. We hypothesized that this dichotomy is due to the inadvertent absence of caspase-11 in previously used caspase-1-deficient mice. To address this, we studied the independent contributions of caspase-1 and -11 during genital Chlamydia infection. Our results show that caspase-11 deficiency was sufficient to recapitulate the effect of the combined absence of both caspase-1 and caspase-11 on oviduct pathology. Further, mice that were deficient for both caspase-1 and -11 but that expressed caspase-11 as a transgene (essentially, caspase-1-deficient mice) had no significant difference in oviduct pathology from control mice. Caspase-11-deficient mice showed reduced dilation in both the oviducts and uterus. To determine the mechanism by which caspase-11-deficient mice developed reduced pathology, the chlamydial burden and immune cell infiltration were determined in the oviducts. In the caspase-11-deficient mice, we observed increased chlamydial burdens in the upper genital tract, which correlated with increased CD4 T cell recruitment, suggesting a contribution of caspase-11 in infection control. Additionally, there were significantly fewer neutrophils in the oviducts of caspase-11-deficient mice, supporting the observed decrease in the incidence of oviduct pathology. Therefore, caspase-11 activation contributes to pathogen control and oviduct disease independently of caspase-1 activation.
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16
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Lausen M, Christiansen G, Bouet Guldbæk Poulsen T, Birkelund S. Immunobiology of monocytes and macrophages during Chlamydia trachomatis infection. Microbes Infect 2018; 21:73-84. [PMID: 30528899 DOI: 10.1016/j.micinf.2018.10.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 10/11/2018] [Accepted: 10/11/2018] [Indexed: 02/03/2023]
Abstract
Infections caused by the intracellular bacterium Chlamydia trachomatis are a global health burden affecting more than 100 million people annually causing damaging long-lasting infections. In this review, we will present and discuss important aspects of the interaction between C. trachomatis and monocytes/macrophages.
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Affiliation(s)
- Mads Lausen
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220 Aalborg Ø, Denmark.
| | - Gunna Christiansen
- Department of Biomedicine, Aarhus University, Wilhelms Meyers Allé 4, 8000 Aarhus, Denmark
| | | | - Svend Birkelund
- Department of Health Science and Technology, Aalborg University, Fredrik Bajers Vej 3b, 9220 Aalborg Ø, Denmark
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17
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CPAF, HSP60 and MOMP antigens elicit pro-inflammatory cytokines production in the peripheral blood mononuclear cells from genital Chlamydia trachomatis-infected patients. Immunobiology 2018; 224:34-41. [PMID: 30477893 DOI: 10.1016/j.imbio.2018.10.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Revised: 10/22/2018] [Accepted: 10/30/2018] [Indexed: 12/26/2022]
Abstract
BACKGROUND Persistent inflammation caused by Chlamydia trachomatis in the female genital compartment represents one of the major causes of pelvic inflammatory disease (PID), ectopic pregnancy and infertility in females. Here, we examined the pro-inflammatory cytokine response following stimulation with three different types of C. trachomatis antigens, viz. chlamydial protease-like factor (CPAF), heat shock protein 60 (HSP60) and major outer membrane protein (MOMP). METHODS A total of 19 patients with genital C. trachomatis infection and 10 age-matched healthy controls were recruited for the study. Peripheral blood mononuclear cells (PBMCs) isolated from genital C. trachomatis-infected females were cultured in the presence of CPAF, HSP60 and MOMP antigens, and cytokines were measured by ELISA assay. RESULTS We reported that pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) were robustly secreted following antigenic exposure. Notably, CPAP and MOMP were more potent in triggering IL-1β, as compared to HSP60. Elevated levels of the proinflammatory cytokines were also noted in the samples infected with plasmid-bearing C. trachomatis as compared to those infected with plasmid-free strains. CONCLUSIONS Our study highlights distinct ability of chlamydial antigens in triggering pro-inflammatory response in the host immune cells.
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18
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Balin BJ, Hammond CJ, Little CS, Hingley ST, Al-Atrache Z, Appelt DM, Whittum-Hudson JA, Hudson AP. Chlamydia pneumoniae: An Etiologic Agent for Late-Onset Dementia. Front Aging Neurosci 2018; 10:302. [PMID: 30356749 PMCID: PMC6189393 DOI: 10.3389/fnagi.2018.00302] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 09/13/2018] [Indexed: 01/02/2023] Open
Abstract
The disease known as late-onset Alzheimer's disease is a neurodegenerative condition recognized as the single most commonform of senile dementia. The condition is sporadic and has been attributed to neuronal damage and loss, both of which have been linked to the accumulation of protein deposits in the brain. Significant progress has been made over the past two decades regarding our overall understanding of the apparently pathogenic entities that arise in the affected brain, both for early-onset disease, which constitutes approximately 5% of all cases, as well as late-onset disease, which constitutes the remainder of cases. Observable neuropathology includes: neurofibrillary tangles, neuropil threads, neuritic senile plaques and often deposits of amyloid around the cerebrovasculature. Although many studies have provided a relatively detailed knowledge of these putatively pathogenic entities, understanding of the events that initiate and support the biological processes generating them and the subsequent observable neuropathology and neurodegeneration remain limited. This is especially true in the case of late-onset disease. Although early-onset Alzheimer's disease has been shown conclusively to have genetic roots, the detailed etiologic initiation of late-onset disease without such genetic origins has remained elusive. Over the last 15 years, current and ongoing work has implicated infection in the etiology and pathogenesis of late-onset dementia. Infectious agents reported to be associated with disease initiation are various, including several viruses and pathogenic bacterial species. We have reported extensively regarding an association between late-onset disease and infection with the intracellular bacterial pathogen Chlamydia pneumoniae. In this article, we review previously published data and recent results that support involvement of this unusual respiratory pathogen in disease induction and development. We further suggest several areas for future research that should elucidate details relating to those processes, and we argue for a change in the designation of the disease based on increased understanding of its clinical attributes.
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Affiliation(s)
- Brian J Balin
- Department of Bio-Medical Sciences, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States
| | - Christine J Hammond
- Department of Bio-Medical Sciences, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States
| | - Christopher Scott Little
- Department of Bio-Medical Sciences, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States
| | - Susan T Hingley
- Department of Bio-Medical Sciences, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States
| | - Zein Al-Atrache
- Department of Bio-Medical Sciences, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States
| | - Denah M Appelt
- Department of Bio-Medical Sciences, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States
| | - Judith A Whittum-Hudson
- Department of Biochemistry, Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Alan P Hudson
- Department of Biochemistry, Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI, United States
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19
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A Macaque Model for Rectal Lymphogranuloma Venereum and Non-Lymphogranuloma Venereum Chlamydia trachomatis: Impact on Rectal Simian/Human Immunodeficiency Virus Acquisition. Sex Transm Dis 2018; 44:551-556. [PMID: 28809773 DOI: 10.1097/olq.0000000000000644] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Sustained genital tract inflammation caused by sexually transmitted infections (STIs) is known to increase risk of vaginal human immunodeficiency virus (HIV) infections but, to our knowledge, there are no nonhuman primate studies that have evaluated its link to rectal HIV acquisition. METHODS Rhesus macaques inoculated with Chlamydia trachomatis (CT) (serovars LGV-L2 and CT-E; n = 7) or saline (n = 7) received up to 20 rectal challenges twice a week of simian/HIV immunodeficiency virus (SHIVSF162p3). SHIV viremia was determined by real-time PCR and Chlamydia infection by APTIMA Combo 2 testing. The rectal cytokine-chemokine levels were evaluated by multiplex bead assays. RESULTS Rectal Chlamydia infection was maintained throughout the study. We did not observe significant differences (P = 1.0) in frequency of SHIV acquisition between the STI and control arms. It took fewer SHIV challenges to infect the STI animals although the difference was not significant (P = 0.59). There were no significant differences in peak plasma viremia between STI and control arms (P = 0.63). The association of plasma viremia with rectal shedding was significantly different by arm (P = 0.038). CONCLUSIONS In the first such study in a macaque model, we did not observe an increased risk of SHIV acquisition due to rectal Chlamydia coinfection. This macaque model can be further developed and expanded to better investigate the impact of different rectal STIs on HIV acquisition.
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20
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Savio LEB, de Andrade Mello P, da Silva CG, Coutinho-Silva R. The P2X7 Receptor in Inflammatory Diseases: Angel or Demon? Front Pharmacol 2018; 9:52. [PMID: 29467654 PMCID: PMC5808178 DOI: 10.3389/fphar.2018.00052] [Citation(s) in RCA: 283] [Impact Index Per Article: 47.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/15/2018] [Indexed: 12/13/2022] Open
Abstract
Under physiological conditions, adenosine triphosphate (ATP) is present at low levels in the extracellular milieu, being massively released by stressed or dying cells. Once outside the cells, ATP and related nucleotides/nucleoside generated by ectonucleotidases mediate a high evolutionary conserved signaling system: the purinergic signaling, which is involved in a variety of pathological conditions, including inflammatory diseases. Extracellular ATP has been considered an endogenous adjuvant that can initiate inflammation by acting as a danger signal through the activation of purinergic type 2 receptors-P2 receptors (P2Y G-protein coupled receptors and P2X ligand-gated ion channels). Among the P2 receptors, the P2X7 receptor is the most extensively studied from an immunological perspective, being involved in both innate and adaptive immune responses. P2X7 receptor activation induces large-scale ATP release via its intrinsic ability to form a membrane pore or in association with pannexin hemichannels, boosting purinergic signaling. ATP acting via P2X7 receptor is the second signal to the inflammasome activation, inducing both maturation and release of pro-inflammatory cytokines, such as IL-1β and IL-18, and the production of reactive nitrogen and oxygen species. Furthermore, the P2X7 receptor is involved in caspases activation, as well as in apoptosis induction. During adaptive immune response, P2X7 receptor modulates the balance between the generation of T helper type 17 (Th17) and T regulatory (Treg) lymphocytes. Therefore, this receptor is involved in several inflammatory pathological conditions. In infectious diseases and cancer, P2X7 receptor can have different and contrasting effects, being an angel or a demon depending on its level of activation, cell studied, type of pathogen, and severity of infection. In neuroinflammatory and neurodegenerative diseases, P2X7 upregulation and function appears to contribute to disease progression. In this review, we deeply discuss P2X7 receptor dual function and its pharmacological modulation in the context of different pathologies, and we also highlight the P2X7 receptor as a potential target to treat inflammatory related diseases.
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Affiliation(s)
- Luiz E B Savio
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paola de Andrade Mello
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Harvard University, Boston, MA, United States
| | - Cleide Gonçalves da Silva
- Division of Vascular Surgery, Department of Surgery, Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Robson Coutinho-Silva
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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21
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Finethy R, Coers J. Sensing the enemy, containing the threat: cell-autonomous immunity to Chlamydia trachomatis. FEMS Microbiol Rev 2018; 40:875-893. [PMID: 28201690 DOI: 10.1093/femsre/fuw027] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 03/31/2016] [Accepted: 07/01/2016] [Indexed: 01/01/2023] Open
Abstract
The bacterium Chlamydia trachomatis is the etiological agent of the most common sexually transmitted infection in North America and Europe. Medical complications resulting from genital C. trachomatis infections arise predominantly in women where the initial infections often remain asymptomatic and thus unrecognized. Untreated asymptomatic infections in women can ascend into the upper genital tract and establish persistence, ultimately resulting in extensive scarring of the reproductive organs, pelvic inflammatory disease, infertility and ectopic pregnancies. Previously resolved C. trachomatis infections fail to provide protective immune memory, and no effective vaccine against C. trachomatis is currently available. Critical determinants of the pathogenesis and immunogenicity of genital C. trachomatis infections are cell-autonomous immune responses. Cell-autonomous immunity describes the ability of an individual host cell to launch intrinsic immune circuits that execute the detection, containment and elimination of cell-invading pathogens. As an obligate intracellular pathogen C. trachomatis is constantly under attack by cell-intrinsic host defenses. Accordingly, C. trachomatis evolved to subvert and co-opt cell-autonomous immune pathways. This review will provide a critical summary of our current understanding of cell-autonomous immunity to C. trachomatis and its role in shaping host resistance, inflammation and adaptive immunity to genital C. trachomatis infections.
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Affiliation(s)
- Ryan Finethy
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Jörn Coers
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.,Department of Immunology, Duke University Medical Center, Durham, NC, USA
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22
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NLRP3 Is a Critical Regulator of Inflammation and Innate Immune Cell Response during Mycoplasma pneumoniae Infection. Infect Immun 2017; 86:IAI.00548-17. [PMID: 29061706 DOI: 10.1128/iai.00548-17] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/16/2017] [Indexed: 12/18/2022] Open
Abstract
Mycoplasma pneumoniae is an atypical bacterial respiratory pathogen known to cause a range of airway inflammation and lung and extrapulmonary pathologies. We recently reported that an M. pneumoniae-derived ADP-ribosylating and vacuolating toxin called community-acquired respiratory distress syndrome (CARDS) toxin is capable of triggering NLRP3 (NLR-family, leucine-rich repeat protein 3) inflammasome activation and interleukin-1β (IL-1β) secretion in macrophages. However, it is unclear whether the NLRP3 inflammasome is important for the immune response during M. pneumoniae acute infection. In the current study, we utilized in vitro and in vivo models of M. pneumoniae infection to characterize the role of the NLRP3 inflammasome during acute infection. M. pneumoniae-infected macrophages deficient for inflammasome components NLRP3, ASC (apoptosis speck-like protein containing a caspase activation and recruitment domain), or caspase-1 failed to process and secrete IL-1β. The MyD88/NF-κB signaling pathway was found to be critical for proinflammatory gene expression in macrophages infected with M. pneumoniae C57BL/6 mice deficient for NLRP3 expression were unable to produce IL-1β in the airways during acute infection, and lack of this inflammatory response led to deficient immune cell activation and delayed bacterial clearance. These findings are the first to report the importance of the NLRP3 inflammasome in regulating the inflammatory response and influencing the progression of M. pneumoniae during acute infection.
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23
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Pan Q, Zhang Q, Chu J, Pais R, Liu S, He C, Eko FO. Chlamydia abortus Pmp18.1 Induces IL-1β Secretion by TLR4 Activation through the MyD88, NF-κB, and Caspase-1 Signaling Pathways. Front Cell Infect Microbiol 2017; 7:514. [PMID: 29326885 PMCID: PMC5741698 DOI: 10.3389/fcimb.2017.00514] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/29/2017] [Indexed: 12/16/2022] Open
Abstract
The polymorphic membrane protein D (Pmp18D) is a 160-kDa outer membrane protein that is conserved and plays an important role in Chlamydia abortus pathogenesis. We have identified an N-terminal fragment of Pmp18D (designated Pmp18.1) as a possible subunit vaccine antigen. In this study, we evaluated the vaccine potential of Pmp18.1 by investigating its ability to induce innate immune responses in dendritic cells and the signaling pathway(s) involved in rPmp18.1-induced IL-1β secretion. We next investigated the immunomodulatory impact of VCG, in comparison with the more established Th1-promoting adjuvants, CpG and FL, on rPmp18.1-mediated innate immune activation. Finally, the effect of siRNA targeting TLR4, MyD88, NF-κB p50, and Caspase-1 mRNA in DCs on IL-1β cytokine secretion was also investigated. Bone marrow-derived dendritic cells (BMDCs) were stimulated with rPmp18.1 in the presence or absence of VCG or CpG or FL and the magnitude of cytokines produced was assessed using a multiplex cytokine ELISA assay. Expression of costimulatory molecules and Toll-like receptors (TLRs) was analyzed by flow cytometry. Quantitation of intracellular levels of myeloid differentiation factor 88 (MyD88), nuclear factor kappa beta (NF-κB p50/p65), and Caspase-1 was evaluated by Western immunoblotting analysis while NF-κB p65 nuclear translocation was assessed by confocal microscopy. The results showed DC stimulation with rPmp18.1 provoked the secretion of proinflammatory cytokines and upregulated expression of TLRs and co-stimulatory molecules associated with DC maturation. These responses were significantly (p ≤ 0.001) enhanced by VCG but not CpG or FL. In addition, rPmp18.1 activated the expression of MyD88, NF-κB p50, and Caspase-1 as well as the nuclear expression of NF-κB p65 in treated DCs. Furthermore, targeting TLR4, MyD88, NF-κB p50, and Caspase-1 mRNA in BMDCs with siRNA significantly reduced their expression levels, resulting in decreased IL-1β cytokine secretion, strongly suggesting their involvement in the rPmp18.1-induced IL-1β cytokine secretion. Taken together, these results indicate that C. abortus Pmp18.1 induces IL-1β secretion by TLR4 activation through the MyD88, NF-κB as well as the Caspase-1 signaling pathways and may be a potential C. abortus vaccine candidate. The vaccine potential of Pmp18.1 will subsequently be evaluated in an appropriate animal model, using VCG as an immunomodulator, following immunization and challenge.
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Affiliation(s)
- Qing Pan
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States.,Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Qiang Zhang
- Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jun Chu
- Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Roshan Pais
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
| | - Shanshan Liu
- Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Cheng He
- Key Lab of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Francis O Eko
- Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA, United States
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24
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Webster SJ, Goodall JC. New concepts in Chlamydia induced inflammasome responses. Microbes Infect 2017; 20:424-431. [PMID: 29248634 DOI: 10.1016/j.micinf.2017.11.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 10/27/2017] [Accepted: 11/21/2017] [Indexed: 02/07/2023]
Abstract
Since the concept of the inflammasome was introduced by Martinon, Burns and Tschopp in 2002, there has been an exponential increase in our understanding of how inflammasomes (caspase activating molecular platforms) regulate innate inflammatory responses to infectious microorganisms. Advances in understanding inflammasome biology have been developed using a range of bacterial pathogens. Recent studies investigating inflammasome responses during Chlamydia infection have provided interesting mechanistic insights in to inflammasome activation during intracellular bacterial infection. This review highlights new concepts regulating inflammasome activation to bacterial infections including: interferon-regulated loss of compartmentalisation, mechanisms of canonical and non-canonical inflammasome activation and their relevance to Chlamydia infections are discussed.
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Affiliation(s)
- Steve J Webster
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
| | - Jane C Goodall
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK.
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25
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McKeithen DN, Omosun YO, Ryans K, Mu J, Xie Z, Simoneaux T, Blas-machado U, Eko FO, Black CM, Igietseme JU, He Q. The emerging role of ASC in dendritic cell metabolism during Chlamydia infection. PLoS One 2017; 12:e0188643. [PMID: 29216217 PMCID: PMC5720709 DOI: 10.1371/journal.pone.0188643] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/10/2017] [Indexed: 11/18/2022] Open
Abstract
Chlamydia trachomatis is a bacterial agent that causes sexually transmitted infections worldwide. The regulatory functions of dendritic cells (DCs) play a major role in protective immunity against Chlamydia infections. Here, we investigated the role of ASC in DCs metabolism and the regulation of DCs activation and function during Chlamydia infection. Following Chlamydia stimulation, maturation and antigen presenting functions were impaired in ASC-/- DCs compared to wild type (WT) DCs, in addition, ASC deficiency induced a tolerant phenotype in Chlamydia stimulated DCs. Using real-time extracellular flux analysis, we showed that activation in Chlamydia stimulated WT DCs is associated with a metabolic change in which mitochondrial oxidative phosphorylation (OXPHOS) is inhibited and the cells become committed to utilizing glucose through aerobic glycolysis for differentiation and antigen presenting functions. However, in ASC-/- DCs Chlamydia-induced metabolic change was prevented and there was a significant effect on mitochondrial morphology. The mitochondria of Chlamydia stimulated ASC-/- DCs had disrupted cristae compared to the normal narrow pleomorphic cristae found in stimulated WT DCs. In conclusion, our results suggest that Chlamydia-mediated activation of DCs is associated with a metabolic transition in which OXPHOS is inhibited, thereby dedicating the DCs to aerobic glycolysis, while ASC deficiency disrupts DCs function by inhibiting the reprogramming of DCs metabolism within the mitochondria, from glycolysis to electron transport chain.
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Affiliation(s)
- Danielle N. McKeithen
- Department Microbiology, Biochemistry, and, Immunology, Morehouse School of Medicine, Atlanta, GA, United States of America
- Department of Biology, Clark Atlanta University, Atlanta, GA, United States of America
| | - Yusuf O. Omosun
- Department Microbiology, Biochemistry, and, Immunology, Morehouse School of Medicine, Atlanta, GA, United States of America
| | - Khamia Ryans
- Department Microbiology, Biochemistry, and, Immunology, Morehouse School of Medicine, Atlanta, GA, United States of America
- Department of Biology, Clark Atlanta University, Atlanta, GA, United States of America
| | - Jing Mu
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, United States of America
| | - Zhonglin Xie
- Center for Molecular and Translational Medicine, Georgia State University, Atlanta, GA, United States of America
| | - Tankya Simoneaux
- Department Microbiology, Biochemistry, and, Immunology, Morehouse School of Medicine, Atlanta, GA, United States of America
| | - Uriel Blas-machado
- College of Veterinary Medicine, University of Georgia, Georgia, Atlanta, United States of America
| | - Francis O. Eko
- Department Microbiology, Biochemistry, and, Immunology, Morehouse School of Medicine, Atlanta, GA, United States of America
| | - Carolyn M. Black
- National Center for Emerging Zoonotic and Infectious Diseases, Centers for Disease Control & Prevention (CDC), Atlanta, GA, United States of America
| | - Joseph U. Igietseme
- Department Microbiology, Biochemistry, and, Immunology, Morehouse School of Medicine, Atlanta, GA, United States of America
- National Center for Emerging Zoonotic and Infectious Diseases, Centers for Disease Control & Prevention (CDC), Atlanta, GA, United States of America
| | - Qing He
- Department Microbiology, Biochemistry, and, Immunology, Morehouse School of Medicine, Atlanta, GA, United States of America
- * E-mail:
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NLRP3 inflammasome activation results in liver inflammation and fibrosis in mice infected with Schistosoma japonicum in a Syk-dependent manner. Sci Rep 2017; 7:8120. [PMID: 28808303 PMCID: PMC5556086 DOI: 10.1038/s41598-017-08689-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 07/06/2017] [Indexed: 02/06/2023] Open
Abstract
Granulomatous and fibrosing inflammation in response to soluble egg antigen (SEA) from Schistosoma japonicum (S. japonicum) is the main pathological process of S. japonicum infection. Inflammasome activation has recently been implicated in the pathogenesis of liver disease. However, the role of inflammasome activation in schistosomiasis-associated liver fibrosis (SSLF) has not been extensively studied. In this study, it is demonstrated that the NLRP3 inflammasome is markedly activated in mouse HSCs both in vivo and in vitro during S. japonicum infection. Furthermore, it is demonstrated that inhibition of NLRP3 inflammasome significantly alleviates the liver inflammation and collagen deposition that are induced by infection with S. japonicum. The mechanism of SEA-induced NLRP3 inflammasome activation is studied in isolated, cultured mouse HSCs and it is shown that SEA-induced NLRP3 inflammasome activation in HSCs is dependent upon the activities of spleen tyrosine kinase (Syk), an enzyme usually associated with a pathogen recognition receptor for fungal pathogens. Moreover, it is demonstrated that Dectin-1 and JNK signaling are also involved in SEA-induced NLRP3 inflammasome activation in HSCs. These data shed new light on the mechanisms of NLRP3 inflammasome activation during an infection with S. japonicum, and further characterize its role in schistosomiasis-associated liver fibrosis (SSLF).
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Chlamydia muridarum Infection of Macrophages Stimulates IL-1 β Secretion and Cell Death via Activation of Caspase-1 in an RIP3-Independent Manner. BIOMED RESEARCH INTERNATIONAL 2017; 2017:1592365. [PMID: 28660207 PMCID: PMC5474261 DOI: 10.1155/2017/1592365] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 05/09/2017] [Indexed: 11/18/2022]
Abstract
Chlamydiae are Gram-negative bacteria, which replicate exclusively in the infected host cells. Infection of the host cells by Chlamydiae stimulates the innate immune system leading to an inflammatory response, which is manifested not only by secretion of proinflammatory cytokines such as IL-1β from monocytes, macrophages, and dendritic cells, but also possibly by cell death mediated by Caspase-1 pyroptosis. RIP3 is a molecular switch that determines the development of necrosis or inflammation. However, the involvement of RIP3 in inflammasome activation by Chlamydia muridarum infection has not been clarified. Here, we assessed the role of RIP3 in synergy with Caspase-1 in the induction of IL-1β production in BMDM after either LPS/ATP or Chlamydia muridarum stimulation. The possibility of pyroptosis and necroptosis interplays and the role of RIP3 in IL-1β production during Chlamydia muridarum infection in BMDM was investigated as well. The data indicated that RIP3 is involved in NLRP3 inflammasome activation in LPS/ATP-stimulated BMDMs but not in Chlamydia muridarum infection. Pyroptosis occurred in BMDM after LPS/ATP stimulation or Chlamydia muridarum infection. Moreover, the results also illuminated the important role of the Caspase-1-mediated pyroptosis process which does not involve RIP3. Taken together, these observations may help shed new light on details in inflammatory signaling pathways activated by Chlamydia muridarum infection.
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Detection of a microbial metabolite by STING regulates inflammasome activation in response to Chlamydia trachomatis infection. PLoS Pathog 2017; 13:e1006383. [PMID: 28570638 PMCID: PMC5453623 DOI: 10.1371/journal.ppat.1006383] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 04/26/2017] [Indexed: 01/25/2023] Open
Abstract
The innate immune system is a critical component of host defence against microbial pathogens, but effective responses require an ability to distinguish between infectious and non-infectious insult to prevent inappropriate inflammation. Using the important obligate intracellular human pathogen Chlamydia trachomatis; an organism that causes significant immunopathology, we sought to determine critical host and pathogen factors that contribute to the induction of inflammasome activation. We assayed inflammasome activation by immunoblotting and ELISA to detect IL-1β processing and LDH release to determine pyroptosis. Using primary murine bone marrow derived macrophages or human monocyte derived dendritic cells, infected with live or attenuated Chlamydia trachomatis we report that the live organism activates both canonical and non-canonical inflammasomes, but only canonical inflammasomes controlled IL-1β processing which preceded pyroptosis. NADPH oxidase deficient macrophages were permissive to Chlamydia trachomatis replication and displayed elevated type-1 interferon and inflammasome activation. Conversely, attenuated, non-replicating Chlamydia trachomatis, primed but did not activate inflammasomes and stimulated reduced type-1 interferon responses. This suggested bacterial replication or metabolism as important factors that determine interferon responses and inflammasome activation. We identified STING but not cGAS as a central mediator of interferon regulated inflammasome activation. Interestingly, exogenous delivery of a Chlamydia trachomatis metabolite and STING ligand—cyclic di-AMP, recovered inflammasome activation to attenuated bacteria in a STING dependent manner thus indicating that a bacterial metabolite is a key factor initiating inflammasome activation through STING, independent of cGAS. These data suggest a potential mechanism of how the innate immune system can distinguish between infectious and non-infectious insult and instigate appropriate immune responses that could be therapeutically targeted. Innate responses to bacterial infection such as Chlamydia trachomatis activate inflammasomes to enable the processing of IL-1β, IL-18 and the induction of an inflammatory form of cell death termed pyroptosis. Inflammasomes are crucial to host defence but require tight regulation in order to prevent inappropriate inflammation and immunopathology. Here, we demonstrate that the pro-inflammatory potential of an attenuated strain of Chlamydia trachomatis, that fails to activate the inflammasome, can be rescued by the addition of a bacterial metabolite. The requirement for this metabolite, highlights a novel mechanism of inflammasome regulation and reveals a crucial role for STING mediated interferon signalling independent of cGAS. These findings further our understanding of how the innate immune system can differentiate between potential infectious and non-infectious threats and mount appropriate immune responses.
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Henning TR, Morris M, Ellis S, Kelley K, Phillips C, Ritter J, Jones T, Nachamkin E, Chen CY, Hong J, Kang J, Patton D, McNicholl J, Papp J, Kersh EN. Development of a rectal sexually transmitted infection (STI) Model in Rhesus macaques using Chlamydia trachomatis serovars E and L 2. J Med Primatol 2017; 46:218-227. [PMID: 28488731 DOI: 10.1111/jmp.12272] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND Rectal STI coinfection models enhance the understanding of rectal HIV transmission risk factors. MATERIALS AND METHODS Rhesus macaques (n=9) were exposed to one of three rectal Chlamydia trachomatis (CT) challenges: C. trachomatis L2 (CT-L2 ); C. trachomatis serovar E (CT-E), followed by CT-L2 ; or CT-E, treatment/clearance, then CT-L2 . Infections were monitored by PCR. Weekly blood and rectal secretion/lavage samples were collected for cytokine analyzes and/or epithelial sloughing, occult, and overt blood determinations. RESULTS Chlamydial infections were successfully established in each animal, with varying degrees of persistence. Mucosal IL-1beta was upregulated in animals consecutively infected with CT-E then CT-L2 (P=.05). Epithelial sloughing was also significantly increased post-infection in this group (P=.0003). CONCLUSIONS This study demonstrates successful rectal infection of rhesus macaques with CT-E and CT-L2 and describes measures of assessing rectal inflammation and pathology. Different infection strategies yield varying inflammatory and pathologic outcomes, providing well-described models for future SIV/SHIV susceptibility studies.
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Affiliation(s)
- Tara R Henning
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | | | | | | | - Christi Phillips
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Jana Ritter
- Division of High Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Tara Jones
- Division of High Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Eli Nachamkin
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Cheng Y Chen
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Jaeyoung Hong
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Joseph Kang
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Dorothy Patton
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA, USA
| | - Janet McNicholl
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - John Papp
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Ellen N Kersh
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
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Yang Z, Cao J, Yang Q, Zhang Y, Han L. NLRP3 p.Q705K and CARD8 p.C10X single nucleotide polymorphisms are not associated with susceptibility to rheumatoid arthritis: a meta-analysis. Int J Rheum Dis 2017; 20:1481-1491. [PMID: 28185410 DOI: 10.1111/1756-185x.13016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Zhaowen Yang
- Department of Immunology; Shandong University School of Medicine; Ji'nan China
- Department of Rheumatology; Jinan Central Hospital affiliated to Shandong University; Ji'nan China
| | - Jin Cao
- Department of Rheumatology; Provincial Hospital affiliated to Shandong University; Ji'nan China
| | - Qingrui Yang
- Department of Rheumatology; Provincial Hospital affiliated to Shandong University; Ji'nan China
| | - Yuanchao Zhang
- Department of Rheumatology; Provincial Hospital affiliated to Shandong University; Ji'nan China
| | - Lihui Han
- Department of Immunology; Shandong University School of Medicine; Ji'nan China
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Inflammasomes in the lung. Mol Immunol 2017; 86:44-55. [PMID: 28129896 DOI: 10.1016/j.molimm.2017.01.014] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 12/11/2022]
Abstract
Innate immune responses act as first line defences upon exposure to potentially noxious stimuli. The innate immune system has evolved numerous intracellular and extracellular receptors that undertake surveillance for potentially damaging particulates. Inflammasomes are intracellular innate immune multiprotein complexes that form and are activated following interaction with these stimuli. Inflammasome activation leads to the cleavage of pro-IL-1β and release of the pro-inflammatory cytokine, IL-1β, which initiates acute phase pro-inflammatory responses, and other responses are also involved (IL-18, pyroptosis). However, excessive activation of inflammasomes can result in chronic inflammation, which has been implicated in a range of chronic inflammatory diseases. The airways are constantly exposed to a wide variety of stimuli. Inflammasome activation and downstream responses clears these stimuli. However, excessive activation may drive the pathogenesis of chronic respiratory diseases such as severe asthma and chronic obstructive pulmonary disease. Thus, there is currently intense interest in the role of inflammasomes in chronic inflammatory lung diseases and in their potential for therapeutic targeting. Here we review the known associations between inflammasome-mediated responses and the development and exacerbation of chronic lung diseases.
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Verma V, Dhanda RS, Møller NF, Yadav M. Inflammasomes and Their Role in Innate Immunity of Sexually Transmitted Infections. Front Immunol 2016; 7:540. [PMID: 27994587 PMCID: PMC5136550 DOI: 10.3389/fimmu.2016.00540] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 11/16/2016] [Indexed: 12/15/2022] Open
Abstract
Inflammasomes are multiprotein complexes present in the cytosol as pattern recognition receptors or as sensors of damage-associated molecular patterns. After recognition of microbe-associated molecular patterns or host-derived danger signals, nucleotide oligomerization domain-like receptors oligomerize to form inflammasomes. The activation of inflammasomes results in an alarm, which is raised to alert adjacent cells through the processing and release of a number of other substrates present in the cytosol. A wide array of inflammasomes and their adapter molecules have been identified in the host’s innate immune system in response to various pathogens. Components of specific pathogens activate different inflammasomes, which once activated in response to pathogen-induced infection, induce the activation of caspases, and the release of mature forms of interleukin-1β (IL-1β) and IL-18. Identifying the mechanisms underlying pathogen-induced inflammasome activation is important if we are to develop novel therapeutic strategies to target sexually transmitted infections (STIs) related pathogens. This information is currently lacking in literature. In this review, we have discussed the role of various inflammasomes in sensing different STIs, as well as the beneficial or detrimental effects of inflammasome signaling in host resistance. Additionally, we have discussed both canonical and non-canonical processing of IL-1β induced with respect to particular infections. Overall, these findings transform our understanding of both the basic biology and clinical relevance of inflammasomes.
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Affiliation(s)
- Vivek Verma
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi , New Delhi , India
| | - Rakesh Singh Dhanda
- Department of Translational and Regenerative Medicine, Post Graduate Institute of Medical Education and Research (PGIMER) , Chandigarh , India
| | | | - Manisha Yadav
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, New Delhi, India; Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
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Zhong G. Chlamydial Plasmid-Dependent Pathogenicity. Trends Microbiol 2016; 25:141-152. [PMID: 27712952 DOI: 10.1016/j.tim.2016.09.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 09/11/2016] [Accepted: 09/19/2016] [Indexed: 10/20/2022]
Abstract
Most Chlamydia species carry a 7.5kb plasmid encoding eight open reading frames conventionally called plasmid glycoproteins 1-8 or pGP1-8. Although the plasmid is not critical for chlamydial growth in vitro, its role in chlamydial pathogenesis is clearly demonstrated in the genital tracts of mice infected with Chlamydia muridarum, a model for investigating the human pathogen Chlamydia trachomatis. Plasmid-free C. trachomatis is also attenuated in both the mouse genital tract and nonhuman primate ocular tissue. Deficiency in pGP3 alone, which is regulated by pGP4, largely reproduced the in vivo but not in vitro phenotypes of the plasmid-free organisms, suggesting that pGP3 is a key in vivo virulence factor. The positive and negative regulations of some chromosomal genes by pGP4 and pGP5, respectively, may allow the plasmid to promote chlamydial adaptation to varied animal tissue environments. The focus of this review is to summarize the progress on the pathogenic functions of the plasmid-encoded open reading frames, which may motivate further investigation of the molecular mechanisms of chlamydial pathogenicity and development of medical utility of the chlamydial plasmid system.
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Affiliation(s)
- Guangming Zhong
- Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.
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Fischer A, Rudel T. Subversion of Cell-Autonomous Host Defense by Chlamydia Infection. Curr Top Microbiol Immunol 2016; 412:81-106. [PMID: 27169422 DOI: 10.1007/82_2016_13] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Obligate intracellular bacteria entirely depend on the metabolites of their host cell for survival and generation of progeny. Due to their lifestyle inside a eukaryotic cell and the lack of any extracellular niche, they have to perfectly adapt to compartmentalized intracellular environment of the host cell and counteract the numerous defense strategies intrinsically present in all eukaryotic cells. This so-called cell-autonomous defense is present in all cell types encountering Chlamydia infection and is in addition closely linked to the cellular innate immune defense of the mammalian host. Cell type and chlamydial species-restricted mechanisms point a long-term evolutionary adaptation that builds the basis of the currently observed host and cell-type tropism among different Chlamydia species. This review will summarize the current knowledge on the strategies pathogenic Chlamydia species have developed to subvert and overcome the multiple mechanisms by which eukaryotic cells defend themselves against intracellular pathogens.
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Affiliation(s)
- Annette Fischer
- Department of Microbiology and Biocenter, University of Würzburg, Am Hubland, 97074, Wuerzburg, Germany
| | - Thomas Rudel
- Department of Microbiology and Biocenter, University of Würzburg, Am Hubland, 97074, Wuerzburg, Germany.
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Cao W, Zou Y, Su S, He Z, Liu Y, Huang Q, Li Z. Chlamydial plasmid-encoded protein pORF5 induces production of IL-1β and IL-18 via NALP3 inflammasome activation and p38 MAPK pathway. Int J Clin Exp Med 2015; 8:20368-20379. [PMID: 26884953 PMCID: PMC4723798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 11/06/2015] [Indexed: 06/05/2023]
Abstract
The pathogenesis of Chlamydia-induced inflammation is poorly understood. pORF5 is the only secreted protein encoded by Chlamydial plasmid. This study aims to investigate the effects of pORF5 on the production of interleukin-1β (IL-1β) and interleukin-18 (IL-18) and the underlying mechanisms of these effects. THP-1 (a human acute monocytic leukemia cell line) cells were stimulated by pORF5 with or without pretreatment with Natch domain, Leucine-rich repeat and PYD-containing protein 3 (NALP3) siRNA, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) siRNA, cysteine aspartate-specific protease-1 (caspase-1) specific inhibitor and p38 mitogen-activated protein kinase (p38 MAPK) inhibitor. IL-1β, IL-18 and caspase-1 expression was detected through both ELISA and qRT-PCR. NALP3 and ASC expression was detected by qRT-PCR. The expression of caspase-1 and phosphorylated-p38 MAPK was detected by western blot analysis. pORF5 induced IL-1β, IL-18, caspase-1 and NALP3 inflammasome expression in THP-1 cells. Caspase-1 inhibitor significantly reduced pORF5-induced IL-1β and IL-18 expression. The siRNAs for NALP3 inflammasome significantly reduced pORF5-induced IL-1β, IL-18 and caspase-1 expression. Furthermore, p38 MAPK inhibitor significantly reduced pORF5-induced IL-1β, IL-18, caspase-1 and NALP3 inflammasome expression. pORF5 could induce production of IL-1β and IL-18 via NALP3 inflammasome activation and p38MAPK pathway. pORF5 protein might play an important role in Chlamydia pathogenesis. This study provides a new insight into the molecular pathogenesis of Chlamydial diseases.
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Affiliation(s)
- Wenjuan Cao
- Pathogenic Biology Institute, School of Medicine, University of South ChinaHengyang 421001, P. R. China
| | - Yan Zou
- Pathogenic Biology Institute, School of Medicine, University of South ChinaHengyang 421001, P. R. China
| | - Shengmei Su
- Pathogenic Biology Institute, School of Medicine, University of South ChinaHengyang 421001, P. R. China
| | - Zhansheng He
- Pathogenic Biology Institute, School of Medicine, University of South ChinaHengyang 421001, P. R. China
| | - Yan Liu
- Pathogenic Biology Institute, School of Medicine, University of South ChinaHengyang 421001, P. R. China
| | - Qiulin Huang
- Department of General Surgery, The First Affiliated Hospital of University of South ChinaHengyang 421001, P. R. China
| | - Zhongyu Li
- Pathogenic Biology Institute, School of Medicine, University of South ChinaHengyang 421001, P. R. China
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug StudyHengyang 421001, P. R. China
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36
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Guanylate binding proteins enable rapid activation of canonical and noncanonical inflammasomes in Chlamydia-infected macrophages. Infect Immun 2015; 83:4740-9. [PMID: 26416908 DOI: 10.1128/iai.00856-15] [Citation(s) in RCA: 112] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/18/2015] [Indexed: 12/27/2022] Open
Abstract
Interferon (IFN)-inducible guanylate binding proteins (GBPs) mediate cell-autonomous host resistance to bacterial pathogens and promote inflammasome activation. The prevailing model postulates that these two GBP-controlled activities are directly linked through GBP-dependent vacuolar lysis. It was proposed that the rupture of pathogen-containing vacuoles (PVs) by GBPs destroyed the microbial refuge and simultaneously contaminated the host cell cytosol with microbial activators of inflammasomes. Here, we demonstrate that GBP-mediated host resistance and GBP-mediated inflammatory responses can be uncoupled. We show that PVs formed by the rodent pathogen Chlamydia muridarum, so-called inclusions, remain free of GBPs and that C. muridarum is impervious to GBP-mediated restrictions on bacterial growth. Although GBPs neither bind to C. muridarum inclusions nor restrict C. muridarum growth, we find that GBPs promote inflammasome activation in C. muridarum-infected macrophages. We demonstrate that C. muridarum infections induce GBP-dependent pyroptosis through both caspase-11-dependent noncanonical and caspase-1-dependent canonical inflammasomes. Among canonical inflammasomes, we find that C. muridarum and the human pathogen Chlamydia trachomatis activate not only NLRP3 but also AIM2. Our data show that GBPs support fast-kinetics processing and secretion of interleukin-1β (IL-1β) and IL-18 by the NLRP3 inflammasome but are dispensable for the secretion of the same cytokines at later times postinfection. Because IFN-γ fails to induce IL-1β transcription, GBP-dependent fast-kinetics inflammasome activation can drive the preferential processing of constitutively expressed IL-18 in IFN-γ-primed macrophages in the absence of prior Toll-like receptor stimulation. Together, our results reveal that GBPs control the kinetics of inflammasome activation and thereby shape macrophage responses to Chlamydia infections.
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37
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Orlowski GM, Colbert JD, Sharma S, Bogyo M, Robertson SA, Rock KL. Multiple Cathepsins Promote Pro-IL-1β Synthesis and NLRP3-Mediated IL-1β Activation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2015; 195:1685-97. [PMID: 26195813 PMCID: PMC4530060 DOI: 10.4049/jimmunol.1500509] [Citation(s) in RCA: 198] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/02/2015] [Indexed: 12/15/2022]
Abstract
Sterile particles induce robust inflammatory responses that underlie the pathogenesis of diseases like silicosis, gout, and atherosclerosis. A key cytokine mediating this response is IL-1β. The generation of bioactive IL-1β by sterile particles is mediated by the NOD-like receptor containing a pyrin domain 3 (NLRP3) inflammasome, although exactly how this occurs is incompletely resolved. Prior studies have found that the cathepsin B inhibitor, Ca074Me, suppresses this response, supporting a model whereby ingested particles disrupt lysosomes and release cathepsin B into the cytosol, somehow activating NLRP3. However, reports that cathepsin B-deficient macrophages have no defect in particle-induced IL-1β generation have questioned cathepsin B's involvement. In this study, we examine the hypothesis that multiple redundant cathepsins (not just cathepsin B) mediate this process by evaluating IL-1β generation in murine macrophages, singly or multiply deficient in cathepsins B, L, C, S and X. Using an activity-based probe, we measure specific cathepsin activity in living cells, documenting compensatory changes in cathepsin-deficient cells, and Ca074Me's dose-dependent cathepsin inhibition profile is analyzed in parallel with its suppression of particle-induced IL-1β secretion. Also, we evaluate endogenous cathepsin inhibitors cystatins C and B. Surprisingly, we find that multiple redundant cathepsins, inhibited by Ca074Me and cystatins, promote pro-IL-1β synthesis, and to our knowledge, we provide the first evidence that cathepsin X plays a nonredundant role in nonparticulate NLRP3 activation. Finally, we find cathepsin inhibitors selectively block particle-induced NLRP3 activation, independently of suppressing pro-IL-1β synthesis. Altogether, we demonstrate that both small molecule and endogenous cathepsin inhibitors suppress particle-induced IL-1β secretion, implicating roles for multiple cathepsins in both pro-IL-1β synthesis and NLRP3 activation.
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Affiliation(s)
- Gregory M Orlowski
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Jeff D Colbert
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Shruti Sharma
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01655
| | - Matthew Bogyo
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305; Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305; and
| | - Stephanie A Robertson
- Sandler Center for Drug Discovery, University of California, San Francisco, San Francisco, CA 94158
| | - Kenneth L Rock
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655;
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Synergistic Costimulatory Effect of Chlamydia pneumoniae with Carbon Nanoparticles on NLRP3 Inflammasome-Mediated Interleukin-1β Secretion in Macrophages. Infect Immun 2015; 83:2917-25. [PMID: 25939513 DOI: 10.1128/iai.02968-14] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 04/30/2015] [Indexed: 11/20/2022] Open
Abstract
The obligate intracellular bacterium Chlamydia pneumoniae is not only a causative agent of community-acquired pneumonia but is also associated with a more serious chronic disease, asthma, which might be exacerbated by air pollution containing carbon nanoparticles. Although a detailed mechanism of exacerbation remains unknown, the proinflammatory cytokine interleukin-1β (IL-1β) is a critical player in the pathogenesis of asthma. C. pneumoniae induces IL-1β in macrophages via NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome activation and Toll-like receptor 2/4 (TLR2/4) stimulation. Carbon nanoparticles, such as carbon nanotubes (CNTs), can also evoke the NLRP3 inflammasome to trigger IL-1β secretion from lipopolysaccharide-primed macrophages. This study assessed whether costimulation of C. pneumoniae with CNTs synergistically enhanced IL-1β secretion from macrophages, and determined the molecular mechanism involved. Enhanced IL-1β secretion from C. pneumoniae-infected macrophages by CNTs was dose and time dependent. Transmission electron microscopy revealed that C. pneumoniae and CNTs were engulfed concurrently by macrophages. Inhibitors of actin polymerization or caspase-1, a component of the inflammasome, significantly blocked IL-1β secretion. Gene silencing using small interfering RNA (siRNA) targeting the NLRP3 gene also abolished IL-1β secretion. Other inhibitors (K(+) efflux inhibitor, cathepsin B inhibitor, and reactive oxygen species-generating inhibitor) also blocked IL-1β secretion. Taken together, these findings demonstrated that CNTs synergistically enhanced IL-1β secretion from C. pneumoniae-infected macrophages via the NLRP3 inflammasome and caspase-1 activation, providing novel insight into our understanding of how C. pneumoniae infection can exacerbate asthma.
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Chacko A, Beagley KW, Timms P, Huston WM. Human Chlamydia pneumoniae isolates demonstrate ability to recover infectivity following penicillin treatment whereas animal isolates do not. FEMS Microbiol Lett 2015; 362:fnv015. [PMID: 25663156 DOI: 10.1093/femsle/fnv015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Chlamydia pneumoniae strains have recently been demonstrated to have substantially different capacities to enter and recover from IFN-γ-induced persistence, depending on whether they are from human or animal host sources. Here, we examined the ability of two human and two animal strains to enter and be rescued from penicillin-induced persistence. The ability to form inclusions after the addition of penicillin was much reduced in the two animal isolates (koala LPCoLN, bandicoot B21) compared to the two human isolates (respiratory AR39 and heart A03). The penicillin treatment resulted in a dose-dependent loss of infectious progeny for all isolates, with the human strains failing to produce infectious progeny at lower doses of penicillin than the animal strains. The most remarkable finding however was the contrasting ability of the isolates to recover infectious progeny production after rescue by removal of the penicillin (at 72 h) and continued culture. The animal isolates both showed virtually no recovery from the penicillin treatment conditions. In contrast, the human isolates showed a significant ability to recovery infectivity, with the heart isolate (A03) showing the most marked recovery. Combined, these data further support the hypothesis that the ability to establish and recover from persistence appears to be enhanced in human C. pneumoniae strains compared to animal strains.
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Affiliation(s)
- Anu Chacko
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Q block, 60 Musk Ave, Kelvin Grove, QLD 4059, Australia
| | - Kenneth W Beagley
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Q block, 60 Musk Ave, Kelvin Grove, QLD 4059, Australia
| | - Peter Timms
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Q block, 60 Musk Ave, Kelvin Grove, QLD 4059, Australia Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia
| | - Wilhelmina M Huston
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Q block, 60 Musk Ave, Kelvin Grove, QLD 4059, Australia
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Aggregatibacter actinomycetemcomitans cytolethal distending toxin activates the NLRP3 inflammasome in human macrophages, leading to the release of proinflammatory cytokines. Infect Immun 2015; 83:1487-96. [PMID: 25644004 DOI: 10.1128/iai.03132-14] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The cytolethal distending toxin (Cdt) is produced from a number of bacteria capable of causing infection and inflammatory disease. Our previous studies with Actinobacillus actinomycetemcomitans Cdt demonstrate not only that the active toxin subunit functions as a phosphatidylinositol-3,4,5-triphosphate (PIP3) phosphatase but also that macrophages exposed to the toxin were stimulated to produce proinflammatory cytokines. We now demonstrate that the Cdt-induced proinflammatory response involves the activation of the NLRP3 inflammasome. Specific inhibitors and short hairpin RNA (shRNA) were employed to demonstrate requirements for NLRP3 and ASC as well as caspase-1. Furthermore, Cdt-mediated inflammasome activation is dependent upon upstream signals, including reactive oxygen species (ROS) generation and Cdt-induced increases in extracellular ATP levels. Increases in extracellular ATP levels contribute to the activation of the P2X7 purinergic receptor, leading to K+ efflux. The relationship between the abilities of the active toxin subunit CdtB to function as a lipid phosphatase, activate the NLRP3 inflammasome, and induce a proinflammatory cytokine response is discussed. These studies provide new insight into the virulence potential of Cdt in mediating the pathogenesis of disease caused by Cdt-producing organisms such as Aggregatibacter actinomycetemcomitans.
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Li X, Liu S, Luo J, Liu A, Tang S, Liu S, Yu M, Zhang Y. Helicobacter pylori induces IL-1β and IL-18 production in human monocytic cell line through activation of NLRP3 inflammasome via ROS signaling pathway. Pathog Dis 2015; 73:ftu024. [DOI: 10.1093/femspd/ftu024] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2014] [Indexed: 12/21/2022] Open
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ADP-ribosylation of NLRP3 by Mycoplasma pneumoniae CARDS toxin regulates inflammasome activity. mBio 2014; 5:mBio.02186-14. [PMID: 25538194 PMCID: PMC4278538 DOI: 10.1128/mbio.02186-14] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The inflammasome is a major regulator of inflammation through its activation of procaspase-1, which cleaves prointerleukin-1β (pro-IL-1β) into its mature form. IL-1β is a critical proinflammatory cytokine that dictates the severity of inflammation associated with a wide spectrum of inflammatory diseases. NLRP3 is a key component of the inflammasome complex, and multiple signals and stimuli trigger formation of the NLRP3 inflammasome complex. In the current study, we uncovered a yet unknown mechanism of NLRP3 inflammasome activation by a pathogen-derived factor. We show that the unique bacterial ADP-ribosylating and vacuolating toxin produced by Mycoplasma pneumoniae and designated community-acquired respiratory distress syndrome (CARDS) toxin activates the NLRP3 inflammasome by colocalizing with the NLRP3 inflammasome and catalyzing the ADP-ribosylation of NLRP3. Mutant full-length CARDS toxin lacking ADP-ribosyltransferase (ADPRT) activity and truncated CARDS toxins unable to bind to macrophages and be internalized failed to activate the NLRP3 inflammasome. These studies demonstrate that CARDS toxin-mediated ADP-ribosylation constitutes an important posttranslational modification of NLRP3, that ADPRT activity of CARDS toxin is essential for NLRP3 inflammasome activation, and that posttranslational ADPRT-mediated modification of the inflammasome is a newly discovered mechanism for inflammasome activation with subsequent release of IL-1β and associated pathologies. Inflammation is a fundamental innate immune response to environmental factors, including infections. The inflammasome represents a multiprotein complex that regulates inflammation via its ability to activate specific proinflammatory cytokines, resulting in an effective host protective response. However, excessive release of proinflammatory cytokines can occur following infection that skews the host response to “hyperinflammation” with exaggerated tissue damage. Mycoplasma pneumoniae, a common bacterial airway pathogen, possesses a unique protein toxin with ADP-ribosyltransferase and vacuolating properties capable of reproducing the robust inflammation and cytopathology associated with mycoplasma infection. Here, we show that the toxin uniquely activates the NLRP3 inflammasome by colocalizing with and ADP-ribosylating NLRP3, possibly leading to “hyperinflammation” and thus uncovering a novel target for therapeutic intervention.
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Jenkins WD, LeVault K, Sutcliffe S. Chlamydia trachomatis infection: possible cofactor for oropharyngeal cancer development? Oral Oncol 2014; 51:e8-9. [PMID: 25500096 DOI: 10.1016/j.oraloncology.2014.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 11/20/2014] [Accepted: 11/23/2014] [Indexed: 12/24/2022]
Affiliation(s)
- Wiley D Jenkins
- Population Health Science Program, Center for Clinical Research, Simmons Cancer Institute, Southern Illinois University School of Medicine, 801 N. Rutledge St., Springfield, IL 62794-9664, United States.
| | - Kelsey LeVault
- Population Health Science Program, Center for Clinical Research, Southern Illinois University School of Medicine, 801 N. Rutledge St., Springfield, IL 62794-9664, United States
| | - Siobhan Sutcliffe
- Division of Public Health Sciences and The Alvin J. Siteman Cancer Center, Department of Surgery, Washington University School of Medicine, 660 S. Euclid Ave., Rm. 2-208S, Box 8100, St. Louis, MO 63110, United States
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Buchacher T, Wiesinger-Mayr H, Vierlinger K, Rüger BM, Stanek G, Fischer MB, Weber V. Human blood monocytes support persistence, but not replication of the intracellular pathogen C. pneumoniae. BMC Immunol 2014; 15:60. [PMID: 25488836 PMCID: PMC4268907 DOI: 10.1186/s12865-014-0060-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 12/01/2014] [Indexed: 01/09/2023] Open
Abstract
Background Intracellular pathogens have devised various mechanisms to subvert the host immune response in order to survive and replicate in host cells. Here, we studied the infection of human blood monocytes with the intracellular pathogen C. pneumoniae and the effect on cytokine and chemokine profiles in comparison to stimulation with LPS. Results Monocytes purified from peripheral blood mononuclear cells by negative depletion were infected with C. pneumoniae. While immunofluorescence confirmed the presence of chlamydial lipopolysaccharide (LPS) in the cytoplasm of infected monocytes, real-time PCR did not provide evidence for replication of the intracellular pathogen. Complementary to PCR, C. pneumoniae infection was confirmed by an oligonucleotide DNA microarray for the detection of intracellular pathogens. Raman microspectroscopy revealed different molecular fingerprints for infected and non-infected monocytes, which were mainly due to changes in lipid and fatty acid content. Stimulation of monocytes with C. pneumoniae or with LPS induced similar profiles of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6, but higher levels of IL-1β, IL-12p40 and IL-12p70 for C. pneumoniae which were statistically significant. C. pneumoniae also induced release of the chemokines MCP-1, MIP-1α and MIP-1β, and CXCL-8, which correlated with TNF-α secretion. Conclusion Infection of human blood monocytes with intracellular pathogens triggers altered cytokine and chemokine pattern as compared to stimulation with extracellular ligands such as LPS. Complementing conventional methods, an oligonucleotide DNA microarray for the detection of intracellular pathogens as well as Raman microspectroscopy provide useful tools to trace monocyte infection. Electronic supplementary material The online version of this article (doi:10.1186/s12865-014-0060-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tanja Buchacher
- Christian Doppler Laboratory for Innovative Therapy Approaches in Sepsis, Danube University Krems, Krems, Austria.
| | | | | | - Beate M Rüger
- Department of Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Vienna, Austria.
| | - Gerold Stanek
- Institute for Hygiene and Applied Immunology, Medical University of Vienna, Vienna, Austria.
| | - Michael B Fischer
- Department of Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Vienna, Austria. .,Department for Health Sciences and Biomedicine, Danube University Krems, Krems, Austria.
| | - Viktoria Weber
- Christian Doppler Laboratory for Innovative Therapy Approaches in Sepsis, Danube University Krems, Krems, Austria. .,Department for Health Sciences and Biomedicine, Danube University Krems, Krems, Austria.
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Shigella IpaH7.8 E3 ubiquitin ligase targets glomulin and activates inflammasomes to demolish macrophages. Proc Natl Acad Sci U S A 2014; 111:E4254-63. [PMID: 25246571 DOI: 10.1073/pnas.1324021111] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
When nucleotide-binding oligomerization domain-like receptors (NLRs) sense cytosolic-invading bacteria, they induce the formation of inflammasomes and initiate an innate immune response. In quiescent cells, inflammasome activity is tightly regulated to prevent excess inflammation and cell death. Many bacterial pathogens provoke inflammasome activity and induce inflammatory responses, including cell death, by delivering type III secreted effectors, the rod component flagellin, and toxins. Recent studies indicated that Shigella deploy multiple mechanisms to stimulate NLR inflammasomes through type III secretion during infection. Here, we show that Shigella induces rapid macrophage cell death by delivering the invasion plasmid antigen H7.8 (IpaH7.8) enzyme 3 (E3) ubiquitin ligase effector via the type III secretion system, thereby activating the NLR family pyrin domain-containing 3 (NLRP3) and NLR family CARD domain-containing 4 (NLRC4) inflammasomes and caspase-1 and leading to macrophage cell death in an IpaH7.8 E3 ligase-dependent manner. Mice infected with Shigella possessing IpaH7.8, but not with Shigella possessing an IpaH7.8 E3 ligase-null mutant, exhibited enhanced bacterial multiplication. We defined glomulin/flagellar-associated protein 68 (GLMN) as an IpaH7.8 target involved in IpaH7.8 E3 ligase-dependent inflammasome activation. This protein originally was identified through its association with glomuvenous malformations and more recently was described as a member of a Cullin ring ligase inhibitor. Modifying GLMN levels through overexpression or knockdown led to reduced or augmented inflammasome activation, respectively. Macrophages stimulated with lipopolysaccharide/ATP induced GLMN puncta that localized with the active form of caspase-1. Macrophages from GLMN(+/-) mice were more responsive to inflammasome activation than those from GLMN(+/+) mice. Together, these results highlight a unique bacterial adaptation that hijacks inflammasome activation via interactions between IpaH7.8 and GLMN.
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Al-Kuhlani M, Rothchild J, Pal S, de la Maza LM, Ouburg S, Morré SA, Dean D, Ojcius DM. TRAIL-R1 is a negative regulator of pro-inflammatory responses and modulates long-term sequelae resulting from Chlamydia trachomatis infections in humans. PLoS One 2014; 9:e93939. [PMID: 24695582 PMCID: PMC3973638 DOI: 10.1371/journal.pone.0093939] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 03/10/2014] [Indexed: 12/17/2022] Open
Abstract
The immune system eliminates Chlamydia trachomatis infection through inflammation. However, uncontrolled inflammation can enhance pathology. In mice, TNF-related apoptosis-inducing ligand receptor (TRAIL-R), known for its effects on apoptosis, also regulates inflammation. In humans, the four homologues of TRAIL-R had never been investigated for effects on inflammation. Here, we examined whether TRAIL-R regulates inflammation during chlamydial infection. We examined TRAIL-R1 single nucleotide polymorphisms (SNPs) in an Ecuadorian cohort with and without C. trachomatis infections. There was a highly significant association for the TRAIL+626 homozygous mutant GG for infection vs no infection in this population. To confirm the results observed in the human population, primary lung fibroblasts and bone marrow-derived macrophages (BMDMs) were isolated from wildtype (WT) and TRAIL-R-deficient mice, and TRAIL-R1 levels in human cervical epithelial cells were depleted by RNA interference. Infection of BMDMs and primary lung fibroblasts with C. trachomatis strain L2, or the murine pathogen C. muridarum, led to higher levels of MIP2 mRNA expression or IL-1β secretion from TRAIL-R-deficient cells than WT cells. Similarly, depletion of TRAIL-R1 expression in human epithelial cells resulted in a higher level of IL-8 mRNA expression and protein secretion during C. trachomatis infection. We conclude that human TRAIL-R1 SNPs and murine TRAIL-R modulate the innate immune response against chlamydial infection. This is the first evidence that human TRAIL-R1 is a negative regulator of inflammation and plays a role in modulating Chlamydia pathogenesis.
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Affiliation(s)
- Mufadhal Al-Kuhlani
- Department of Molecular Cell Biology, and Health Sciences Research Institute, University of California Merced, Merced, California, United States of America
| | - James Rothchild
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute, Oakland, California, United States of America
| | - Sukumar Pal
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, California, United States of America
| | - Luis M. de la Maza
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, California, United States of America
| | - Sander Ouburg
- Laboratory of Immunogenetics, Medical Microbiology and Infection Prevention, Research School V-ICI, VU University Medical Center, Amsterdam, The Netherlands
| | - Servaas A. Morré
- Laboratory of Immunogenetics, Medical Microbiology and Infection Prevention, Research School V-ICI, VU University Medical Center, Amsterdam, The Netherlands
- Institute of Public Health Genomics, Department of Genetics and Cell Biology, Research School GROW, University of Maastricht, Maastricht, The Netherlands
| | - Deborah Dean
- Center for Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute, Oakland, California, United States of America
- Graduate Program in Bioengineering, University of California, Berkeley and San Francisco, California, United States of America
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - David M. Ojcius
- Department of Molecular Cell Biology, and Health Sciences Research Institute, University of California Merced, Merced, California, United States of America
- * E-mail:
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Abstract
The elaboration of an effective immune response against pathogenic microbes such as viruses, intracellular bacteria or protozoan parasites relies on the recognition of microbial products called pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs). Ligation of the PRRs leads to synthesis and secretion of pro-inflammatory cytokines and chemokines. Infected cells and other stressed cells also release host-cell derived molecules, called damage-associated molecular patterns (DAMPs, danger signals, or alarmins), which are generic markers for damage. DAMPs are recognized by specific receptors on both immune and nonimmune cells, which, depending on the target cell and the cellular context, can lead to cell differentiation or cell death, and either inflammation or inhibition of inflammation. Recent research has revealed that DAMPs and PAMPs synergize to permit secretion of pro-inflammatory cytokines such as interleukin-1β (IL-1β): PAMPs stimulate synthesis of pro-IL-1β, but not its secretion; while DAMPs can stimulate assembly of an inflammasome containing, usually, a Nod-like receptor (NLR) member, and activation of the protease caspase-1, which cleaves pro-IL-1β into IL-1β, allowing its secretion. Other NLR members do not participate in formation of inflammasomes but play other essential roles in regulation of the innate immune response.
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Affiliation(s)
- Najwane Saïd-Sadier
- Molecular Cell Biology, and Health Sciences Research Institute, University of California, Merced, CA, USA
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Cunha LD, Zamboni DS. Subversion of inflammasome activation and pyroptosis by pathogenic bacteria. Front Cell Infect Microbiol 2013; 3:76. [PMID: 24324933 PMCID: PMC3840304 DOI: 10.3389/fcimb.2013.00076] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 10/23/2013] [Indexed: 12/16/2022] Open
Abstract
Activation of the inflammasome occurs in response to a notably high number of pathogenic microbes and is a broad innate immune response that effectively contributes to restriction of pathogen replication and generation of adaptive immunity. Activation of these platforms leads to caspase-1- and/or caspase-11-dependent secretion of proteins, including cytokines, and induction of a specific form of cell death called pyroptosis, which directly or indirectly contribute for restriction of pathogen replication. Not surprisingly, bona fide intracellular pathogens developed strategies for manipulation of cell death to guarantee intracellular replication. In this sense, the remarkable advances in the knowledge of the inflammasome field have been accompanied by several reports characterizing the inhibition of this platform by several pathogenic bacteria. Herein, we review some processes used by pathogenic bacteria, including Yersinia spp., Pseudomonas aeruginosa, Vibrio parahaemolyticus, Chlamydia trachomatis, Francisella tularensis, Shigella flexneri, Legionella pneumophila, and Coxiella burnetii to evade the activation of the inflammasome and the induction of pyroptosis.
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Affiliation(s)
- Larissa D Cunha
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo (FMRP/USP) Ribeirão Preto, Brazil
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Kim JJ, Jo EK. NLRP3 inflammasome and host protection against bacterial infection. J Korean Med Sci 2013; 28:1415-23. [PMID: 24133343 PMCID: PMC3792593 DOI: 10.3346/jkms.2013.28.10.1415] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 08/20/2013] [Indexed: 01/30/2023] Open
Abstract
The inflammasome is a multi-protein complex that induces maturation of inflammatory cytokines interleukin (IL)-1β and IL-18 through activation of caspase-1. Several nucleotide binding oligomerization domain-like receptor family members, including NLRP3, recognize unique microbial and danger components and play a central role in inflammasome activation. The NLRP3 inflammasome is critical for maintenance of homeostasis against pathogenic infections. However, inflammasome activation acts as a double-edged sword for various bacterial infections. When the IL-1 family of cytokines is secreted excessively, they cause tissue damage and extensive inflammatory responses that are potentially hazardous for the host. Emerging evidence has shown that diverse bacterial pathogens or their components negatively regulate inflammasome activation to escape the immune response. In this review, we discuss the current knowledge of the roles and regulation of the NLRP3 inflammasome during bacterial infections. Activation and regulation of the NLRP3 inflammasome should be tightly controlled to prevent virulence and pathology during infections. Understanding the roles and regulatory mechanisms of the NLRP3 inflammasome is essential for developing potential treatment approaches against pathogenic infections.
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Affiliation(s)
- Jwa-Jin Kim
- Department of Microbiology and Infection Signaling Network Research Center, Chungnam National University School of Medicine, Daejeon, Korea
| | - Eun-Kyeong Jo
- Department of Microbiology and Infection Signaling Network Research Center, Chungnam National University School of Medicine, Daejeon, Korea
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