1
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Schmidt S, Mondino S, Gomez-Valero L, Escoll P, Mascarenhas DPA, Gonçalves A, Camara PHM, Garcia Rodriguez FJ, Rusniok C, Sachse M, Moya-Nilges M, Fontaine T, Zamboni DS, Buchrieser C. The unique Legionella longbeachae capsule favors intracellular replication and immune evasion. PLoS Pathog 2024; 20:e1012534. [PMID: 39259722 DOI: 10.1371/journal.ppat.1012534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 08/26/2024] [Indexed: 09/13/2024] Open
Abstract
Legionella longbeachae and Legionella pneumophila are the most common causative agents of Legionnaires' disease. While the clinical manifestations caused by both species are similar, species-specific differences exist in environmental niches, disease epidemiology, and genomic content. One such difference is the presence of a genomic locus predicted to encode a capsule. Here, we show that L. longbeachae indeed expresses a capsule in post-exponential growth phase as evidenced by electron microscopy analyses, and that capsule expression is abrogated when deleting a capsule transporter gene. Capsule purification and its analysis via HLPC revealed the presence of a highly anionic polysaccharide that is absent in the capsule mutant. The capsule is important for replication and virulence in vivo in a mouse model of infection and in the natural host Acanthamoeba castellanii. It has anti-phagocytic function when encountering innate immune cells such as human macrophages and it is involved in the low cytokine responses in mice and in human monocyte derived macrophages, thus dampening the innate immune response. Thus, the here characterized L. longbeachae capsule is a novel virulence factor, unique among the known Legionella species, which may aid L. longbeachae to survive in its specific niches and which partly confers L. longbeachae its unique infection characteristics.
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Affiliation(s)
- Silke Schmidt
- Institut Pasteur, Université Paris Cité, Biologie des Bactéries Intracellulaires, CNRS UMR 6047, Paris, France
- Sorbonne Université, Collège Doctoral, Paris, France
| | - Sonia Mondino
- Institut Pasteur, Université Paris Cité, Biologie des Bactéries Intracellulaires, CNRS UMR 6047, Paris, France
| | - Laura Gomez-Valero
- Institut Pasteur, Université Paris Cité, Biologie des Bactéries Intracellulaires, CNRS UMR 6047, Paris, France
| | - Pedro Escoll
- Institut Pasteur, Université Paris Cité, Biologie des Bactéries Intracellulaires, CNRS UMR 6047, Paris, France
| | | | - Augusto Gonçalves
- Department of Cell Biology, Medical School of Ribeirão Preto, FMRP/USP, Ribeirão Preto, Brazil
| | - Pedro H M Camara
- Department of Cell Biology, Medical School of Ribeirão Preto, FMRP/USP, Ribeirão Preto, Brazil
| | | | - Christophe Rusniok
- Institut Pasteur, Université Paris Cité, Biologie des Bactéries Intracellulaires, CNRS UMR 6047, Paris, France
| | - Martin Sachse
- UTechS UBI, Centre de Ressources et Recherches Technologiques, Institut Pasteur, Paris, France
| | - Maryse Moya-Nilges
- UTechS UBI, Centre de Ressources et Recherches Technologiques, Institut Pasteur, Paris, France
| | - Thierry Fontaine
- Biologie et Pathogénicité fongiques, Institut Pasteur, Paris, France
| | - Dario S Zamboni
- Department of Cell Biology, Medical School of Ribeirão Preto, FMRP/USP, Ribeirão Preto, Brazil
| | - Carmen Buchrieser
- Institut Pasteur, Université Paris Cité, Biologie des Bactéries Intracellulaires, CNRS UMR 6047, Paris, France
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2
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Giuliano CJ, Wei KJ, Harling FM, Waldman BS, Farringer MA, Boydston EA, Lan TCT, Thomas RW, Herneisen AL, Sanderlin AG, Coppens I, Dvorin JD, Lourido S. CRISPR-based functional profiling of the Toxoplasma gondii genome during acute murine infection. Nat Microbiol 2024; 9:2323-2343. [PMID: 38977907 DOI: 10.1038/s41564-024-01754-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Accepted: 06/07/2024] [Indexed: 07/10/2024]
Abstract
Examining host-pathogen interactions in animals can capture aspects of infection that are obscured in cell culture. Using CRISPR-based screens, we functionally profile the entire genome of the apicomplexan parasite Toxoplasma gondii during murine infection. Barcoded gRNAs enabled bottleneck detection and mapping of population structures within parasite lineages. Over 300 genes with previously unknown roles in infection were found to modulate parasite fitness in mice. Candidates span multiple axes of host-parasite interaction. Rhoptry Apical Surface Protein 1 was characterized as a mediator of host-cell tropism that facilitates repeated invasion attempts. GTP cyclohydrolase I was also required for fitness in mice and druggable through a repurposed compound, 2,4-diamino-6-hydroxypyrimidine. This compound synergized with pyrimethamine against T. gondii and malaria-causing Plasmodium falciparum parasites. This work represents a complete survey of an apicomplexan genome during infection of an animal host and points to novel interfaces of host-parasite interaction.
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Affiliation(s)
| | - Kenneth J Wei
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | | | - Benjamin S Waldman
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | - Madeline A Farringer
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, USA
- Biological Sciences in Public Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | | | | | - Raina W Thomas
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | - Alice L Herneisen
- Whitehead Institute, Cambridge, MA, USA
- Biology Department, MIT, Cambridge, MA, USA
| | | | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Jeffrey D Dvorin
- Division of Infectious Diseases, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Sebastian Lourido
- Whitehead Institute, Cambridge, MA, USA.
- Biology Department, MIT, Cambridge, MA, USA.
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3
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Mascarenhas DP, Zamboni DS. Innate immune responses and monocyte-derived phagocyte recruitment in protective immunity to pathogenic bacteria: insights from Legionella pneumophila. Curr Opin Microbiol 2024; 80:102495. [PMID: 38908045 DOI: 10.1016/j.mib.2024.102495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 04/18/2024] [Accepted: 05/24/2024] [Indexed: 06/24/2024]
Abstract
Legionella species are Gram-negative intracellular bacteria that evolved in soil and freshwater environments, where they infect and replicate within various unicellular protozoa. The primary virulence factor of Legionella is the expression of a type IV secretion system (T4SS), which contributes to the translocation of effector proteins that subvert biological processes of the host cells. Because of its evolution in unicellular organisms, T4SS effector proteins are not adapted to subvert specific mammalian signaling pathways and immunity. Consequently, Legionella pneumophila has emerged as an interesting infection model for investigating immune responses against pathogenic bacteria in multicellular organisms. This review highlights recent advances in our understanding of mammalian innate immunity derived from studies involving L. pneumophila. This includes recent insights into inflammasome-mediated mechanisms restricting bacterial replication in macrophages, mechanisms inducing cell death in response to infection, induction of effector-triggered immunity, activation of specific pulmonary cell types in mammalian lungs, and the protective role of recruiting monocyte-derived cells to infected lungs.
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Affiliation(s)
- Danielle Pa Mascarenhas
- Department of Cell Biology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP 14049-900, Brazil
| | - Dario S Zamboni
- Department of Cell Biology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP 14049-900, Brazil.
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4
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Barber MF, Fitzgerald JR. Mechanisms of host adaptation by bacterial pathogens. FEMS Microbiol Rev 2024; 48:fuae019. [PMID: 39003250 PMCID: PMC11308195 DOI: 10.1093/femsre/fuae019] [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: 04/15/2024] [Revised: 07/02/2024] [Accepted: 07/24/2024] [Indexed: 07/15/2024] Open
Abstract
The emergence of new infectious diseases poses a major threat to humans, animals, and broader ecosystems. Defining factors that govern the ability of pathogens to adapt to new host species is therefore a crucial research imperative. Pathogenic bacteria are of particular concern, given dwindling treatment options amid the continued expansion of antimicrobial resistance. In this review, we summarize recent advancements in the understanding of bacterial host species adaptation, with an emphasis on pathogens of humans and related mammals. We focus particularly on molecular mechanisms underlying key steps of bacterial host adaptation including colonization, nutrient acquisition, and immune evasion, as well as suggest key areas for future investigation. By developing a greater understanding of the mechanisms of host adaptation in pathogenic bacteria, we may uncover new strategies to target these microbes for the treatment and prevention of infectious diseases in humans, animals, and the broader environment.
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Affiliation(s)
- Matthew F Barber
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403, United States
- Department of Biology, University of Oregon, Eugene, OR 97403, United States
| | - J Ross Fitzgerald
- The Roslin Institute, University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
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5
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Neuber J, Lang C, Aurass P, Flieger A. Tools and mechanisms of vacuolar escape leading to host egress in Legionella pneumophila infection: Emphasis on bacterial phospholipases. Mol Microbiol 2024; 121:368-384. [PMID: 37891705 DOI: 10.1111/mmi.15183] [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: 06/28/2023] [Revised: 09/29/2023] [Accepted: 10/06/2023] [Indexed: 10/29/2023]
Abstract
The phenomenon of host cell escape exhibited by intracellular pathogens is a remarkably versatile occurrence, capable of unfolding through lytic or non-lytic pathways. Among these pathogens, the bacterium Legionella pneumophila stands out, having adopted a diverse spectrum of strategies to disengage from their host cells. A pivotal juncture that predates most of these host cell escape modalities is the initial escape from the intracellular compartment. This critical step is increasingly supported by evidence suggesting the involvement of several secreted pathogen effectors, including lytic proteins. In this intricate landscape, L. pneumophila emerges as a focal point for research, particularly concerning secreted phospholipases. While nestled within its replicative vacuole, the bacterium deftly employs both its type II (Lsp) and type IVB (Dot/Icm) secretion systems to convey phospholipases into either the phagosomal lumen or the host cell cytoplasm. Its repertoire encompasses numerous phospholipases A (PLA), including three enzymes-PlaA, PlaC, and PlaD-bearing the GDSL motif. Additionally, there are 11 patatin-like phospholipases A as well as PlaB. Furthermore, the bacterium harbors three extracellular phospholipases C (PLCs) and one phospholipase D. Within this comprehensive review, we undertake an exploration of the pivotal role played by phospholipases in the broader context of phagosomal and host cell egress. Moreover, we embark on a detailed journey to unravel the established and potential functions of the secreted phospholipases of L. pneumophila in orchestrating this indispensable process.
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Affiliation(s)
- Jonathan Neuber
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Christina Lang
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Philipp Aurass
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Antje Flieger
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
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6
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Wan T, Wang Y, He K, Zhu S. Microbial sensing in the intestine. Protein Cell 2023; 14:824-860. [PMID: 37191444 PMCID: PMC10636641 DOI: 10.1093/procel/pwad028] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 05/04/2023] [Indexed: 05/17/2023] Open
Abstract
The gut microbiota plays a key role in host health and disease, particularly through their interactions with the immune system. Intestinal homeostasis is dependent on the symbiotic relationships between the host and the diverse gut microbiota, which is influenced by the highly co-evolved immune-microbiota interactions. The first step of the interaction between the host and the gut microbiota is the sensing of the gut microbes by the host immune system. In this review, we describe the cells of the host immune system and the proteins that sense the components and metabolites of the gut microbes. We further highlight the essential roles of pattern recognition receptors (PRRs), the G protein-coupled receptors (GPCRs), aryl hydrocarbon receptor (AHR) and the nuclear receptors expressed in the intestinal epithelial cells (IECs) and the intestine-resident immune cells. We also discuss the mechanisms by which the disruption of microbial sensing because of genetic or environmental factors causes human diseases such as the inflammatory bowel disease (IBD).
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Affiliation(s)
- Tingting Wan
- Division of Life Sciences and Medicine, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Institute of Immunology, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Yalong Wang
- Division of Life Sciences and Medicine, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Institute of Immunology, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Kaixin He
- Division of Life Sciences and Medicine, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Institute of Immunology, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Shu Zhu
- Division of Life Sciences and Medicine, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Institute of Immunology, School of Basic Medical Sciences, University of Science and Technology of China, Hefei 230027, China
- Department of Digestive Disease, Division of Life Sciences and Medicine, The First Affiliated Hospital of USTC, University of Science and Technology of China, Hefei 230001, China
- Institute of Health and Medicine, Hefei Comprehensive National Science Center, Hefei 230601, China
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7
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Zhang J, Brodsky IE, Shin S. Yersinia deploys type III-secreted effectors to evade caspase-4 inflammasome activation in human cells. mBio 2023; 14:e0131023. [PMID: 37615436 PMCID: PMC10653943 DOI: 10.1128/mbio.01310-23] [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: 06/15/2023] [Accepted: 07/06/2023] [Indexed: 08/25/2023] Open
Abstract
IMPORTANCE Yersinia are responsible for significant disease burden in humans, ranging from recurrent disease outbreaks (yersiniosis) to pandemics (Yersinia pestis plague). Together with rising antibiotic resistance rates, there is a critical need to better understand Yersinia pathogenesis and host immune mechanisms, as this information will aid in developing improved immunomodulatory therapeutics. Inflammasome responses in human cells are less studied relative to murine models of infection, though recent studies have uncovered key differences in inflammasome responses between mice and humans. Here, we dissect human intestinal epithelial cell and macrophage inflammasome responses to Yersinia pseudotuberculosis. Our findings provide insight into species- and cell type-specific differences in inflammasome responses to Yersinia.
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Affiliation(s)
- Jenna Zhang
- Department of Microbiology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
| | - Igor E. Brodsky
- Department of Pathobiology, University of Pennsylvania, School of Veterinary Medicine, Philadelphia, Pennsylvania, USA
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, USA
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8
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Egan MS, O’Rourke EA, Mageswaran SK, Zuo B, Martynyuk I, Demissie T, Hunter EN, Bass AR, Chang YW, Brodsky IE, Shin S. Inflammasomes primarily restrict cytosolic Salmonella replication within human macrophages. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.17.549348. [PMID: 37503120 PMCID: PMC10370064 DOI: 10.1101/2023.07.17.549348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Salmonella enterica serovar Typhimurium is a facultative intracellular pathogen that utilizes its type III secretion systems (T3SSs) to inject virulence factors into the host cell and colonize the host. In turn, a subset of cytosolic immune receptors respond to T3SS ligands by forming multimeric signaling complexes called inflammasomes, which activate caspases that induce interleukin-1 (IL-1) family cytokine release and an inflammatory form of cell death called pyroptosis. Human macrophages mount a multifaceted inflammasome response to Salmonella infection that ultimately restricts intracellular bacterial replication. However, how inflammasomes restrict Salmonella replication remains unknown. We find that caspase-1 is essential for mediating inflammasome responses to Salmonella and subsequent restriction of bacterial replication within human macrophages, with caspase-4 contributing as well. We also demonstrate that the downstream pore-forming protein gasdermin D (GSDMD) and ninjurin-1 (NINJ1), a mediator of terminal cell lysis, play a role in controlling Salmonella replication in human macrophages. Notably, in the absence of inflammasome responses, we observed hyperreplication of Salmonella within the cytosol of infected cells, and we also observed increased bacterial replication within vacuoles, suggesting that inflammasomes control Salmonella replication primarily within the cytosol and also within vacuoles. These findings reveal that inflammatory caspases and pyroptotic factors mediate inflammasome responses that restrict the subcellular localization of intracellular Salmonella replication within human macrophages.
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Affiliation(s)
- Marisa S. Egan
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Emily A. O’Rourke
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Shrawan Kumar Mageswaran
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Biao Zuo
- Electron Microscopy Resource Laboratory, Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Inna Martynyuk
- Electron Microscopy Resource Laboratory, Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Tabitha Demissie
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Emma N. Hunter
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Antonia R. Bass
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Yi-Wei Chang
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Igor E. Brodsky
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA
| | - Sunny Shin
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
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9
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Zhang J, Brodsky IE, Shin S. Yersinia Type III-Secreted Effectors Evade the Caspase-4 Inflammasome in Human Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.24.525473. [PMID: 36747770 PMCID: PMC9900831 DOI: 10.1101/2023.01.24.525473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Yersinia are gram-negative zoonotic bacteria that use a type III secretion system (T3SS) to inject Yersinia outer proteins (Yops) into the host cytosol to subvert essential components of innate immune signaling. However, Yersinia virulence activities can elicit activation of inflammasomes, which lead to inflammatory cell death and cytokine release to contain infection. Yersinia activation and evasion of inflammasomes have been characterized in murine macrophages but remain poorly defined in human cells, particularly intestinal epithelial cells (IECs), a primary site of intestinal Yersinia infection. In contrast to murine macrophages, we find that in both human IECs and macrophages, Yersinia pseudotuberculosis T3SS effectors enable evasion of the caspase-4 inflammasome, which senses cytosolic lipopolysaccharide (LPS). The antiphagocytic YopE and YopH, as well as the translocation regulator YopK, were collectively responsible for evading inflammasome activation, in part by inhibiting Yersinia internalization mediated by YadA and β1-integrin signaling. These data provide insight into the mechanisms of Yersinia-mediated inflammasome activation and evasion in human cells, and reveal species-specific differences underlying regulation of inflammasome responses to Yersinia .
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Affiliation(s)
- Jenna Zhang
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
| | - Igor E. Brodsky
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania 19104
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
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10
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Pollock TY, Vázquez Marrero VR, Brodsky IE, Shin S. TNF licenses macrophages to undergo rapid caspase-1, -11, and -8-mediated cell death that restricts Legionella pneumophila infection. PLoS Pathog 2023; 19:e1010767. [PMID: 37279255 DOI: 10.1371/journal.ppat.1010767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 05/25/2023] [Indexed: 06/08/2023] Open
Abstract
The inflammatory cytokine tumor necrosis factor (TNF) is necessary for host defense against many intracellular pathogens, including Legionella pneumophila. Legionella causes the severe pneumonia Legionnaires' disease and predominantly affects individuals with a suppressed immune system, including those receiving therapeutic TNF blockade to treat autoinflammatory disorders. TNF induces pro-inflammatory gene expression, cellular proliferation, and survival signals in certain contexts, but can also trigger programmed cell death in others. It remains unclear, however, which of the pleiotropic functions of TNF mediate control of intracellular bacterial pathogens like Legionella. In this study, we demonstrate that TNF signaling licenses macrophages to die rapidly in response to Legionella infection. We find that TNF-licensed cells undergo rapid gasdermin-dependent, pyroptotic death downstream of inflammasome activation. We also find that TNF signaling upregulates components of the inflammasome response, and that the caspase-11-mediated non-canonical inflammasome is the first inflammasome to be activated, with caspase-1 and caspase-8 mediating delayed pyroptotic death. We find that all three caspases are collectively required for optimal TNF-mediated restriction of bacterial replication in macrophages. Furthermore, caspase-8 is required for control of pulmonary Legionella infection. These findings reveal a TNF-dependent mechanism in macrophages for activating rapid cell death that is collectively mediated by caspases-1, -8, and -11 and subsequent restriction of Legionella infection.
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Affiliation(s)
- Tzvi Y Pollock
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Víctor R Vázquez Marrero
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Igor E Brodsky
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania, United States of America
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
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11
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Ngwaga T, Chauhan D, Salberg AG, Shames SR. Effector-mediated subversion of proteasome activator (PA)28αβ enhances host defense against Legionella pneumophila under inflammatory and oxidative stress conditions. PLoS Pathog 2023; 19:e1011473. [PMID: 37347796 PMCID: PMC10321654 DOI: 10.1371/journal.ppat.1011473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 07/05/2023] [Accepted: 06/09/2023] [Indexed: 06/24/2023] Open
Abstract
Legionella pneumophila is a natural pathogen of amoebae that causes Legionnaires' Disease in immunocompromised individuals via replication within macrophages. L. pneumophila virulence and intracellular replication hinges on hundreds of Dot/Icm-translocated effector proteins, which are essential for biogenesis of the replication-permissive Legionella-containing vacuole (LCV). However, effector activity can also enhance mammalian host defense via effector-triggered immunity. The L. pneumophila effector LegC4 is important for virulence in amoebae but enhances host defense against L. pneumophila in the mouse lung and, uniquely, within macrophages activated with either tumor necrosis factor (TNF) or interferon (IFN)-γ. The mechanism by which LegC4 potentiates cytokine-mediated host defense in macrophages is unknown. Here, we found that LegC4 enhances cytokine-mediated phagolysosomal fusion with Legionella-containing vacuole (LCV) and binds host proteasome activator (PA)28α, which forms a heterooligomer with PA28β to facilitate ubiquitin-independent proteasomal degradation of oxidant-damaged (carbonylated) proteins. We found that oxidative stress was sustained in the presence of LegC4 and that the LegC4 restriction phenotype was relieved in PA28αβ-deficient macrophages and in the lungs of mice in vivo. Our data also show that oxidative stress is sufficient for LegC4-mediated restriction in macrophages producing PA28αβ. PA28αβ has been traditionally associated with antigen presentation; however, our data support a novel mechanism whereby effector-mediated subversion of PA28αβ enhances cell-autonomous host defense against L. pneumophila under inflammatory and oxidative stress conditions. This work provides a solid foundation to evaluate induced proteasome regulators as mediators of innate immunity.
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Affiliation(s)
- Tshegofatso Ngwaga
- Division of Biology, Kansas State University, Manhattan, Kansas, United States of America
| | - Deepika Chauhan
- Division of Biology, Kansas State University, Manhattan, Kansas, United States of America
| | - Abigail G. Salberg
- Division of Biology, Kansas State University, Manhattan, Kansas, United States of America
| | - Stephanie R. Shames
- Division of Biology, Kansas State University, Manhattan, Kansas, United States of America
- Department of Microbiology & Molecular Genetics, Michigan State University, East Lansing, Michigan, United States of America
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12
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Egan MS, Zhang J, Shin S. Human and mouse NAIP/NLRC4 inflammasome responses to bacterial infection. Curr Opin Microbiol 2023; 73:102298. [PMID: 37058933 PMCID: PMC10225321 DOI: 10.1016/j.mib.2023.102298] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 02/15/2023] [Accepted: 02/22/2023] [Indexed: 04/16/2023]
Abstract
Intracellular immune complexes known as inflammasomes sense breaches of cytosolic sanctity. Inflammasomes promote downstream proinflammatory events, including interleukin-1 (IL-1) family cytokine release and pyroptotic cell death. The nucleotide-binding leucine-rich repeat family, apoptosis inhibitory protein/nucleotide-binding leucine-rich repeat family, caspase recruitment domain (CARD) domain-containing protein 4 (NAIP/NLRC4) inflammasome is involved in a range of pathogenic and protective inflammatory processes in mammalian hosts. In particular, the NAIP/NLRC4 inflammasome responds to flagellin and components of the virulence-associated type III secretion (T3SS) apparatus in the host cytosol, thereby allowing it to be a critical mediator of host defense during bacterial infection. Notable species- and cell type-specific differences exist in NAIP/NLRC4 inflammasome responses to bacterial pathogens. With a focus on Salmonella enterica serovar Typhimurium as a model pathogen, we review differences between murine and human NAIP/NLRC4 inflammasome responses. Differences in NAIP/NLRC4 inflammasome responses across species and cell types may have arisen in part due to evolutionary pressures.
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Affiliation(s)
- Marisa S Egan
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Jenna Zhang
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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Grayczyk JP, Egan MS, Liu L, Aunins E, Wynosky-Dolfi MA, Canna S, Minn AJ, Shin S, Brodsky IE. TLR priming licenses NAIP inflammasome activation by immunoevasive ligands. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.04.539437. [PMID: 37205371 PMCID: PMC10187295 DOI: 10.1101/2023.05.04.539437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
NLR family, apoptosis inhibitory proteins (NAIPs) detect bacterial flagellin and structurally related components of bacterial type III secretion systems (T3SS), and recruit NLR family, CARD domain containing protein 4 (NLRC4) and caspase-1 into an inflammasome complex that induces pyroptosis. NAIP/NLRC4 inflammasome assembly is initiated by the binding of a single NAIP to its cognate ligand, but a subset of bacterial flagellins or T3SS structural proteins are thought to evade NAIP/NLRC4 inflammasome sensing by not binding to their cognate NAIPs. Unlike other inflammasome components such as NLRP3, AIM2, or some NAIPs, NLRC4 is constitutively present in resting macrophages, and not thought to be regulated by inflammatory signals. Here, we demonstrate that Toll-like receptor (TLR) stimulation upregulates NLRC4 transcription and protein expression in murine macrophages, which licenses NAIP detection of evasive ligands. TLR-induced NLRC4 upregulation and NAIP detection of evasive ligands required p38 MAPK signaling. In contrast, TLR priming in human macrophages did not upregulate NLRC4 expression, and human macrophages remained unable to detect NAIP-evasive ligands even following priming. Critically, ectopic expression of either murine or human NLRC4 was sufficient to induce pyroptosis in response to immunoevasive NAIP ligands, indicating that increased levels of NLRC4 enable the NAIP/NLRC4 inflammasome to detect these normally evasive ligands. Altogether, our data reveal that TLR priming tunes the threshold for NAIP/NLRC4 inflammasome activation and enables inflammasome responses against immunoevasive or suboptimal NAIP ligands.
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Affiliation(s)
- James P Grayczyk
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Marisa S Egan
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Luying Liu
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Emily Aunins
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Meghan A Wynosky-Dolfi
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
| | - Scott Canna
- Department of Pediatrics, Division of Rheumatology, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Andy J Minn
- Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Abramson Family Cancer Research Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Parker Institute for Cancer Immunotherapy, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
- Mark Foundation Center for Immunotherapy, Immune Signaling, and Radiation, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Igor E Brodsky
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA
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14
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Rhee JH, Khim K, Puth S, Choi Y, Lee SE. Deimmunization of flagellin adjuvant for clinical application. Curr Opin Virol 2023; 60:101330. [PMID: 37084463 DOI: 10.1016/j.coviro.2023.101330] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 03/23/2023] [Indexed: 04/23/2023]
Abstract
Flagellin is the cognate ligand for host pattern recognition receptors, toll-like receptor 5 (TLR5) in the cell surface, and NAIP5/NLRC4 inflammasome in the cytosol. TLR5-binding domain is located in D1 domain, where crucial amino acid sequences are conserved among diverse bacteria. The highly conserved C-terminal 35 amino acids of flagellin were proved to be responsible for the inflammasome activation by binding to NAIP5. D2/D3 domains, located in the central region and exposed to the outside surface of flagellar filament, are heterogeneous across bacterial species and highly immunogenic. Taking advantage of TLR5- and NLRC4-stimulating activities, flagellin has been actively developed as a vaccine adjuvant and immunotherapeutic. Because of its immunogenicity, there exist worries concerning diminished efficacy and possible reactogenicity after repeated administration. Deimmunization of flagellin derivatives while preserving the TLR5/NLRC4-mediated immunomodulatory activity should be the most reasonable option for clinical application. This review describes strategies and current achievements in flagellin deimmunization.
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Affiliation(s)
- Joon Haeng Rhee
- Clinical Vaccine R&D Center, Chonnam National University, Hwasun-gun, Jeonnam, Republic of Korea; Combinatorial Tumor Immunotherapy MRC, Chonnam National University Medical School, Hwasun-gun, Jeonnam, Republic of Korea; Department of Microbiology, Chonnam National University Medical School, Hwasun-gun, Jeonnam, Republic of Korea.
| | - Koemchhoy Khim
- Clinical Vaccine R&D Center, Chonnam National University, Hwasun-gun, Jeonnam, Republic of Korea; Combinatorial Tumor Immunotherapy MRC, Chonnam National University Medical School, Hwasun-gun, Jeonnam, Republic of Korea
| | - Sao Puth
- Clinical Vaccine R&D Center, Chonnam National University, Hwasun-gun, Jeonnam, Republic of Korea; Combinatorial Tumor Immunotherapy MRC, Chonnam National University Medical School, Hwasun-gun, Jeonnam, Republic of Korea
| | - Yoonjoo Choi
- Combinatorial Tumor Immunotherapy MRC, Chonnam National University Medical School, Hwasun-gun, Jeonnam, Republic of Korea; Department of Microbiology, Chonnam National University Medical School, Hwasun-gun, Jeonnam, Republic of Korea
| | - Shee Eun Lee
- Clinical Vaccine R&D Center, Chonnam National University, Hwasun-gun, Jeonnam, Republic of Korea; Immunotherapy Innovation Center, Hwasun-gun, Jeonnam, Republic of Korea
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15
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Shakiba Y, Vorobyev PO, Naumenko VA, Kochetkov DV, Zajtseva KV, Valikhov MP, Yusubalieva GM, Gumennaya YD, Emelyanov EA, Semkina AS, Baklaushev VP, Chumakov PM, Lipatova AV. Oncolytic Efficacy of a Recombinant Vaccinia Virus Strain Expressing Bacterial Flagellin in Solid Tumor Models. Viruses 2023; 15:v15040828. [PMID: 37112810 PMCID: PMC10142208 DOI: 10.3390/v15040828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 04/29/2023] Open
Abstract
Oncolytic viral therapy is a promising novel approach to cancer treatment. Oncolytic viruses cause tumor regression through direct cytolysis on the one hand and recruiting and activating immune cells on the other. In this study, to enhance the antitumor efficacy of the thymidine kinase-deficient vaccinia virus (VV, Lister strain), recombinant variants encoding bacterial flagellin (subunit B) of Vibrio vulnificus (LIVP-FlaB-RFP), firefly luciferase (LIVP-Fluc-RFP) or red fluorescent protein (LIVP-RFP) were developed. The LIVP-FLuc-RFP strain demonstrated exceptional onco-specificity in tumor-bearing mice, detected by the in vivo imaging system (IVIS). The antitumor efficacy of these variants was explored in syngeneic murine tumor models (B16 melanoma, CT26 colon cancer and 4T1 breast cancer). After intravenous treatment with LIVP-FlaB-RFP or LIVP-RFP, all mice tumor models exhibited tumor regression, with a prolonged survival rate in comparison with the control mice. However, superior oncolytic activity was observed in the B16 melanoma models treated with LIVP-FlaB-RFP. Tumor-infiltrated lymphocytes and the cytokine analysis of the serum and tumor samples from the melanoma-xenografted mice treated with these virus variants demonstrated activation of the host's immune response. Thus, the expression of bacterial flagellin by VV can enhance its oncolytic efficacy against immunosuppressive solid tumors.
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Affiliation(s)
- Yasmin Shakiba
- Moscow Institute of Physics and Technology, 141701 Dolgoprudny, Russia
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Pavel O Vorobyev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Victor A Naumenko
- Department of Neurobiology, V. Serbsky Federal Medical Research Centre of Psychiatry and Narcology of the Ministry of Health of the Russian Federation, 119034 Moscow, Russia
| | - Dmitry V Kochetkov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Ksenia V Zajtseva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Marat P Valikhov
- Department of Neurobiology, V. Serbsky Federal Medical Research Centre of Psychiatry and Narcology of the Ministry of Health of the Russian Federation, 119034 Moscow, Russia
- Department of Medical Nanobiotechnology, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Gaukhar M Yusubalieva
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Federal Research and Clinical Center for Specialized Types of Medical Care and Medical Technologies FMBA of Russia, 115682 Moscow, Russia
| | - Yana D Gumennaya
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Egor A Emelyanov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Alevtina S Semkina
- Department of Medical Nanobiotechnology, Pirogov Russian National Research Medical University, 117997 Moscow, Russia
| | - Vladimir P Baklaushev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
- Federal Research and Clinical Center for Specialized Types of Medical Care and Medical Technologies FMBA of Russia, 115682 Moscow, Russia
| | - Peter M Chumakov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Anastasia V Lipatova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
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16
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Ma X, Liang X, Li Y, Feng Q, Cheng K, Ma N, Zhu F, Guo X, Yue Y, Liu G, Zhang T, Liang J, Ren L, Zhao X, Nie G. Modular-designed engineered bacteria for precision tumor immunotherapy via spatiotemporal manipulation by magnetic field. Nat Commun 2023; 14:1606. [PMID: 36959204 PMCID: PMC10036336 DOI: 10.1038/s41467-023-37225-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 03/07/2023] [Indexed: 03/25/2023] Open
Abstract
Micro-nano biorobots based on bacteria have demonstrated great potential for tumor diagnosis and treatment. The bacterial gene expression and drug release should be spatiotemporally controlled to avoid drug release in healthy tissues and undesired toxicity. Herein, we describe an alternating magnetic field-manipulated tumor-homing bacteria developed by genetically modifying engineered Escherichia coli with Fe3O4@lipid nanocomposites. After accumulating in orthotopic colon tumors in female mice, the paramagnetic Fe3O4 nanoparticles enable the engineered bacteria to receive and convert magnetic signals into heat, thereby initiating expression of lysis proteins under the control of a heat-sensitive promoter. The engineered bacteria then lyse, releasing its anti-CD47 nanobody cargo, that is pre-expressed and within the bacteria. The robust immunogenicity of bacterial lysate cooperates with anti-CD47 nanobody to activate both innate and adaptive immune responses, generating robust antitumor effects against not only orthotopic colon tumors but also distal tumors in female mice. The magnetically engineered bacteria also enable the constant magnetic field-controlled motion for enhanced tumor targeting and increased therapeutic efficacy. Thus, the gene expression and drug release behavior of tumor-homing bacteria can be spatiotemporally manipulated in vivo by a magnetic field, achieving tumor-specific CD47 blockage and precision tumor immunotherapy.
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Affiliation(s)
- Xiaotu Ma
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
- Department of Ultrasound, Peking University Third Hospital, Beijing, 100191, China
- IGDB-NCNST Joint Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiaolong Liang
- Department of Ultrasound, Peking University Third Hospital, Beijing, 100191, China
| | - Yao Li
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
- The Higher Educational Key Laboratory of Biomedical Engineering of Fujian Province, Research Center of Biomedical Engineering of Xiamen, Department of Biomaterials, College of Materials, Xiamen University, Xiamen, Fujian, 361005, China
| | - Qingqing Feng
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Keman Cheng
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Nana Ma
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Fei Zhu
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Xinjing Guo
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Yale Yue
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Guangna Liu
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Tianjiao Zhang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Jie Liang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Lei Ren
- The Higher Educational Key Laboratory of Biomedical Engineering of Fujian Province, Research Center of Biomedical Engineering of Xiamen, Department of Biomaterials, College of Materials, Xiamen University, Xiamen, Fujian, 361005, China
| | - Xiao Zhao
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
- IGDB-NCNST Joint Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Guangjun Nie
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
- The GBA National Institute for Nanotechnology Innovation, Guangdong, 510700, China.
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17
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Giuliano CJ, Wei KJ, Harling FM, Waldman BS, Farringer MA, Boydston EA, Lan TCT, Thomas RW, Herneisen AL, Sanderlin AG, Coppens I, Dvorin JD, Lourido S. Functional profiling of the Toxoplasma genome during acute mouse infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.05.531216. [PMID: 36945434 PMCID: PMC10028831 DOI: 10.1101/2023.03.05.531216] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
Within a host, pathogens encounter a diverse and changing landscape of cell types, nutrients, and immune responses. Examining host-pathogen interactions in animal models can therefore reveal aspects of infection absent from cell culture. We use CRISPR-based screens to functionally profile the entire genome of the model apicomplexan parasite Toxoplasma gondii during mouse infection. Barcoded gRNAs were used to track mutant parasite lineages, enabling detection of bottlenecks and mapping of population structures. We uncovered over 300 genes that modulate parasite fitness in mice with previously unknown roles in infection. These candidates span multiple axes of host-parasite interaction, including determinants of tropism, host organelle remodeling, and metabolic rewiring. We mechanistically characterized three novel candidates, including GTP cyclohydrolase I, against which a small-molecule inhibitor could be repurposed as an antiparasitic compound. This compound exhibited antiparasitic activity against T. gondii and Plasmodium falciparum, the most lethal agent of malaria. Taken together, we present the first complete survey of an apicomplexan genome during infection of an animal host, and point to novel interfaces of host-parasite interaction that may offer new avenues for treatment.
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Affiliation(s)
| | - Kenneth J. Wei
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | - Faye M. Harling
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | | | - Madeline A. Farringer
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, USA
- Biological Sciences in Public Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | | | | | - Raina W. Thomas
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | - Alice L. Herneisen
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
| | | | - Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | - Jeffrey D. Dvorin
- Division of Infectious Diseases, Boston Children’s Hospital, Boston, Massachusetts, USA
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
| | - Sebastian Lourido
- Whitehead Institute, Cambridge, MA
- Biology Department, MIT, Cambridge, MA
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18
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Intrabacterial Regulation of a Cytotoxic Effector by Its Cognate Metaeffector Promotes Legionella pneumophila Virulence. mSphere 2023; 8:e0055222. [PMID: 36598225 PMCID: PMC9942577 DOI: 10.1128/msphere.00552-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Legionella pneumophila is a natural pathogen of unicellular protozoa that can opportunistically infect macrophages and cause Legionnaires' Disease. Intracellular replication is driven by hundreds of bacterial effector proteins that are translocated into infected host cells by a Dot/Icm type IV secretion system. L. pneumophila effectors are temporally regulated in part by a unique family of translocated regulatory effectors, termed metaeffectors, which bind and modulate the function of a cognate effector in host cells. Regulation of the cytotoxic effector SidI by its cognate metaeffector, MesI, is critical for L. pneumophila virulence in natural and opportunistic hosts. MesI binds and negatively regulates SidI activity in vitro, but how impaired regulation of SidI impairs L. pneumophila intracellular replication is unclear. Using a chromosomally encoded inducible expression system, we found that SidI was toxic to L. pneumophila when uncoupled from MesI. SidI enzymatic activity was required for intrabacterial toxicity since L. pneumophila growth was unaffected by induced expression of a catalytically inactive sidI allele. We also found that MesI translocation into host cells was dispensable for intracellular replication and that MesI-deficient bacteria were rapidly degraded within host cells. These data suggest that MesI promotes L. pneumophila intracellular replication by regulating SidI within the bacterium and reveal a unique role for intrabacterial effector regulation by a translocated metaeffector in L. pneumophila virulence. IMPORTANCE Legionella pneumophila replicates within phagocytic host cells using hundreds of effector protein virulence factors, which canonically subvert the function of host proteins and pathways. L. pneumophila encodes a unique family of translocated effectors called metaeffectors, which bind and regulate the function of a cognate effector in host cells. The metaeffector MesI promotes L. pneumophila virulence by regulating the cytotoxic effector SidI; however, the MesI regulatory mechanism is poorly understood. We discovered a unique intrabacterial role for MesI in L. pneumophila virulence. When uncoupled from MesI, SidI was toxic to L. pneumophila in vitro and triggered robust bacterial degradation in host cells. Furthermore, translocation of MesI was dispensable for intracellular replication, demonstrating that intrabacterial regulation of SidI contributes to L. pneumophila virulence. These data show a novel and important role for translocated effector activity within the bacterium, which challenges the dogma that L. pneumophila effectors function exclusively within host cells.
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19
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Klatt AB, Diersing C, Lippmann J, Mayer-Lambertz S, Stegmann F, Fischer S, Caesar S, Fiocca Vernengo F, Hönzke K, Hocke AC, Ruland J, Witzenrath M, Lepenies B, Opitz B. CLEC12A Binds to Legionella pneumophila but Has No Impact on the Host's Antibacterial Response. Int J Mol Sci 2023; 24:ijms24043891. [PMID: 36835297 PMCID: PMC9967056 DOI: 10.3390/ijms24043891] [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: 01/24/2023] [Revised: 02/10/2023] [Accepted: 02/12/2023] [Indexed: 02/17/2023] Open
Abstract
Legionella pneumophila is an intracellular pathogen that can cause severe pneumonia after the inhalation of contaminated aerosols and replication in alveolar macrophages. Several pattern recognition receptors (PRRs) have been identified that contribute to the recognition of L. pneumophila by the innate immune system. However, the function of the C-type lectin receptors (CLRs), which are mainly expressed by macrophages and other myeloid cells, remains largely unexplored. Here, we used a library of CLR-Fc fusion proteins to search for CLRs that can bind the bacterium and identified the specific binding of CLEC12A to L. pneumophila. Subsequent infection experiments in human and murine macrophages, however, did not provide evidence for a substantial role of CLEC12A in controlling innate immune responses to the bacterium. Consistently, antibacterial and inflammatory responses to Legionella lung infection were not significantly influenced by CLEC12A deficiency. Collectively, CLEC12A is able to bind to L. pneumophila-derived ligands but does not appear to play a major role in the innate defense against L. pneumophila.
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Affiliation(s)
- Ann-Brit Klatt
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Christina Diersing
- Institute for Immunology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
| | - Juliane Lippmann
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- Max Planck Institute for Infection Biology, Vector Biology, 10117 Berlin, Germany
| | - Sabine Mayer-Lambertz
- Institute for Immunology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
| | - Felix Stegmann
- Institute for Immunology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
| | - Swantje Fischer
- Institute for Immunology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
| | - Sandra Caesar
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Facundo Fiocca Vernengo
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Katja Hönzke
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- Faculty of Health Sciences Brandenburg, Brandenburg University of Technology Cottbus—Senftenberg, 03046 Cottbus, Germany
| | - Andreas C. Hocke
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Center for Lung Research (DZL), Augustenburger Platz 1, 13353 Berlin, Germany
| | - Jürgen Ruland
- Institute of Clinical Chemistry and Pathobiochemistry, School of Medicine, Technical University of Munich, 80333 Munich, Germany
- Center for Translational Cancer Research (TranslaTUM), 81675 Munich, Germany
- German Cancer Consortium (DKTK), Partner Site Munich, 80336 Munich, Germany
- German Research Center (DKFZ), 69120 Heidelberg, Germany
- German Center for Infection Research (DZIF), Partner Site Munich, 17493 Greifswald, Germany
| | - Martin Witzenrath
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Center for Lung Research (DZL), Augustenburger Platz 1, 13353 Berlin, Germany
| | - Bernd Lepenies
- Institute for Immunology, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
- Research Center for Emerging Infections and Zoonoses, University of Veterinary Medicine Hannover, 30559 Hannover, Germany
- Correspondence: (B.L.); (B.O.)
| | - Bastian Opitz
- Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Center for Lung Research (DZL), Augustenburger Platz 1, 13353 Berlin, Germany
- Correspondence: (B.L.); (B.O.)
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20
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Ataide MA, Manin GZ, Oliveira SS, Guerra RO, Zamboni DS. Inflammasome activation and CCR2-mediated monocyte-derived dendritic cell recruitment restrict Legionella pneumophila infection. Eur J Immunol 2023; 53:e2249985. [PMID: 36427489 DOI: 10.1002/eji.202249985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 09/22/2022] [Accepted: 11/24/2022] [Indexed: 11/27/2022]
Abstract
Flagellin-induced NAIP/NLRC4 inflammasome activation and pyroptosis are critical events restricting Legionella pneumophila infection. However, the cellular and molecular dynamics of the in vivo responses against this bacterium are still unclear. We have found temporal coordination of two independent innate immunity pathways in controlling Legionella infection, the inflammasome activation and the CCR2-mediated Mo-DC recruitment. Inflammasome activation was an important player at the early stage of infection by lowering the numbers of bacteria for an efficient bacterial clearance conferred by the Mo-DC at the late stage of the infection. Mo-DC emergence highly depended on CCR2-signaling and dispensed inflammasome activation and pyroptosis. Also, Mo-DC compartment did not rely on the inflammasome machinery to deliver proper immune responses and was the most abundant cytokine-producing among the monocyte-derived cells in the infected lung. Importantly, when the CCR2- and NLRC4-dependent axes of response were simultaneously ablated, we observed an aggravated bacterial burden in the lung of infected mice. Taken together, we showed that inflammasome activation and CCR2-mediated immune response interplay in distinct pathways to restrict pulmonary bacterial infection. These findings extend our understanding of the in vivo integration and cooperation of different innate immunity arms in controlling infectious agents.
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Affiliation(s)
- Marco A Ataide
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Graziele Z Manin
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Samuel S Oliveira
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Rhanoica O Guerra
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Dario S Zamboni
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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21
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Yang JL, Li D, Zhan XY. Concept about the Virulence Factor of Legionella. Microorganisms 2022; 11:microorganisms11010074. [PMID: 36677366 PMCID: PMC9867486 DOI: 10.3390/microorganisms11010074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/23/2022] [Accepted: 12/23/2022] [Indexed: 12/29/2022] Open
Abstract
Pathogenic species of Legionella can infect human alveolar macrophages through Legionella-containing aerosols to cause a disease called Legionellosis, which has two forms: a flu-like Pontiac fever and severe pneumonia named Legionnaires' disease (LD). Legionella is an opportunistic pathogen that frequently presents in aquatic environments as a biofilm or protozoa parasite. Long-term interaction and extensive co-evolution with various genera of amoebae render Legionellae pathogenic to infect humans and also generate virulence differentiation and heterogeneity. Conventionally, the proteins involved in initiating replication processes and human macrophage infections have been regarded as virulence factors and linked to pathogenicity. However, because some of the virulence factors are associated with the infection of protozoa and macrophages, it would be more accurate to classify them as survival factors rather than virulence factors. Given that the molecular basis of virulence variations among non-pathogenic, pathogenic, and highly pathogenic Legionella has not yet been elaborated from the perspective of virulence factors, a comprehensive explanation of how Legionella infects its natural hosts, protozoans, and accidental hosts, humans is essential to show a novel concept regarding the virulence factor of Legionella. In this review, we overviewed the pathogenic development of Legionella from protozoa, the function of conventional virulence factors in the infections of protozoa and macrophages, the host's innate immune system, and factors involved in regulating the host immune response, before discussing a probably new definition for the virulence factors of Legionella.
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22
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Pan Y, Cai W, Huang J, Cheng A, Wang M, Yin Z, Jia R. Pyroptosis in development, inflammation and disease. Front Immunol 2022; 13:991044. [PMID: 36189207 PMCID: PMC9522910 DOI: 10.3389/fimmu.2022.991044] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 08/30/2022] [Indexed: 11/15/2022] Open
Abstract
In the early 2000s, caspase-1, an important molecule that has been shown to be involved in the regulation of inflammation, cell survival and diseases, was given a new function: regulating a new mode of cell death that was later defined as pyroptosis. Since then, the inflammasome, the inflammatory caspases (caspase-4/5/11) and their substrate gasdermins (gasdermin A, B, C, D, E and DFNB59) has also been reported to be involved in the pyroptotic pathway, and this pathway is closely related to the development of various diseases. In addition, important apoptotic effectors caspase-3/8 and granzymes have also been reported to b involved in the induction of pyroptosis. In our article, we summarize findings that help define the roles of inflammasomes, inflammatory caspases, gasdermins, and other mediators of pyroptosis, and how they determine cell fate and regulate disease progression.
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Affiliation(s)
- Yuhong Pan
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Wenjun Cai
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Juan Huang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- *Correspondence: Anchun Cheng, ; Renyong Jia,
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Zhongqiong Yin
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, China
- *Correspondence: Anchun Cheng, ; Renyong Jia,
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23
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Maciag K, Raychowdhury R, Smith K, Schneider AM, Coers J, Mumbach MR, Schwartz S, Hacohen N. IRF3 inhibits IFN-γ-mediated restriction of intracellular pathogens in macrophages independently of IFNAR. J Leukoc Biol 2022; 112:257-271. [PMID: 34826345 PMCID: PMC9550582 DOI: 10.1002/jlb.3a0218-069rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Revised: 10/25/2021] [Accepted: 10/30/2021] [Indexed: 01/14/2023] Open
Abstract
Macrophages use an array of innate immune sensors to detect intracellular pathogens and to tailor effective antimicrobial responses. In addition, extrinsic activation with the cytokine IFN-γ is often required as well to tip the scales of the host-pathogen balance toward pathogen restriction. However, little is known about how host-pathogen sensing impacts the antimicrobial IFN-γ-activated state. It was observed that in the absence of IRF3, a key downstream component of pathogen sensing pathways, IFN-γ-primed macrophages more efficiently restricted the intracellular bacterium Legionella pneumophila and the intracellular protozoan parasite Trypanosoma cruzi. This effect did not require IFNAR, the receptor for Type I IFNs known to be induced by IRF3, nor the sensing adaptors MyD88/TRIF, MAVS, or STING. This effect also did not involve differential activation of STAT1, the major signaling protein downstream of both Type 1 and Type 2 IFN receptors. IRF3-deficient macrophages displayed a significantly altered IFN-γ-induced gene expression program, with up-regulation of microbial restriction factors such as Nos2. Finally, we found that IFN-γ-primed but not unprimed macrophages largely excluded the activated form of IRF3 from the nucleus following bacterial infection. These data are consistent with a relationship of mutual inhibition between IRF3 and IFN-γ-activated programs, possibly as a component of a partially reversible mechanism for modulating the activity of potent innate immune effectors (such as Nos2) in the context of intracellular infection.
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Affiliation(s)
- Karolina Maciag
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA,Program in Immunology, Harvard Medical School, Boston, MA 02115, USA,Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | | | - Karen Smith
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Alexis M. Schneider
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jörn Coers
- Departments of Molecular Genetics and Microbiology and Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | | | | | - Nir Hacohen
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA,Program in Immunology, Harvard Medical School, Boston, MA 02115, USA,Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Charlestown, MA 02129, USA
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24
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Lara-Reyna S, Caseley EA, Topping J, Rodrigues F, Jimenez Macias J, Lawler SE, McDermott MF. Inflammasome activation: from molecular mechanisms to autoinflammation. Clin Transl Immunology 2022; 11:e1404. [PMID: 35832835 PMCID: PMC9262628 DOI: 10.1002/cti2.1404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/09/2022] Open
Abstract
Inflammasomes are assembled by innate immune sensors that cells employ to detect a range of danger signals and respond with pro-inflammatory signalling. Inflammasomes activate inflammatory caspases, which trigger a cascade of molecular events with the potential to compromise cellular integrity and release the IL-1β and IL-18 pro-inflammatory cytokines. Several molecular mechanisms, working in concert, ensure that inflammasome activation is tightly regulated; these include NLRP3 post-translational modifications, ubiquitination and phosphorylation, as well as single-domain proteins that competitively bind to key inflammasome components, such as the CARD-only proteins (COPs) and PYD-only proteins (POPs). These diverse regulatory systems ensure that a suitable level of inflammation is initiated to counteract any cellular insult, while simultaneously preserving tissue architecture. When inflammasomes are aberrantly activated can drive excessive production of pro-inflammatory cytokines and cell death, leading to tissue damage. In several autoinflammatory conditions, inflammasomes are aberrantly activated with subsequent development of clinical features that reflect the degree of underlying tissue and organ damage. Several of the resulting disease complications may be successfully controlled by anti-inflammatory drugs and/or specific cytokine inhibitors, in addition to more recently developed small-molecule inhibitors. In this review, we will explore the molecular processes underlying the activation of several inflammasomes and highlight their role during health and disease. We also describe the detrimental effects of these inflammasome complexes, in some pathological conditions, and review current therapeutic approaches as well as future prospective treatments.
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Affiliation(s)
- Samuel Lara-Reyna
- Institute of Microbiology and Infection University of Birmingham Birmingham UK
| | - Emily A Caseley
- School of Biomedical Sciences, Faculty of Biological Sciences University of Leeds Leeds UK
| | - Joanne Topping
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, St James's University Hospital University of Leeds Leeds UK
| | - François Rodrigues
- AP-HP, Hôpital Tenon, Sorbonne Université, Service de Médecine interne Centre de Référence des Maladies Auto-inflammatoires et des Amyloses d'origine inflammatoire (CEREMAIA) Paris France
| | - Jorge Jimenez Macias
- Harvey Cushing Neuro-Oncology Laboratories, Department of Neurosurgery, Brigham and Women's Hospital Harvard Medical School Boston Massachusetts USA.,Brown Cancer Centre, Department of Pathology and Laboratory Medicine Brown University Providence Rhode Island USA
| | - Sean E Lawler
- Harvey Cushing Neuro-Oncology Laboratories, Department of Neurosurgery, Brigham and Women's Hospital Harvard Medical School Boston Massachusetts USA.,Brown Cancer Centre, Department of Pathology and Laboratory Medicine Brown University Providence Rhode Island USA
| | - Michael F McDermott
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, St James's University Hospital University of Leeds Leeds UK
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25
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Dai F, Guo M, Shao Y, Li C. Vibrio splendidus flagellin C binds tropomodulin to induce p38 MAPK-mediated p53-dependent coelomocyte apoptosis in Echinodermata. J Biol Chem 2022; 298:102091. [PMID: 35654141 PMCID: PMC9249833 DOI: 10.1016/j.jbc.2022.102091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/09/2022] [Accepted: 05/13/2022] [Indexed: 12/27/2022] Open
Abstract
As a typical pathogen-associated molecular pattern, bacterial flagellin can bind Toll-like receptor 5 and the intracellular NAIP5 receptor component of the NLRC4 inflammasome to induce immune responses in mammals. However, these flagellin receptors are generally poorly understood in lower animal species. In this study, we found that the isolated flagellum of Vibrio splendidus AJ01 destroyed the integrity of the tissue structure of coelomocytes and promoted apoptosis in the sea cucumber Apostichopus japonicus. To further investigate the molecular mechanism, the novel intracellular LRR domain-containing protein tropomodulin (AjTmod) was identified as a protein that interacts with flagellin C (FliC) with a dissociation constant (Kd) of 0.0086 ± 0.33 μM by microscale thermophoresis assay. We show that knockdown of AjTmod also depressed FliC-induced apoptosis of coelomocytes. Further functional analysis with different inhibitor treatments revealed that the interaction between AjTmod and FliC could specifically activate p38 MAPK, but not JNK or ERK MAP kinases. We demonstrate that the transcription factor p38 is then translocated into the nucleus, where it mediates the expression of p53 to induce coelomocyte apoptosis. Our findings provide the first evidence that intracellular AjTmod serves as a novel receptor of FliC and mediates p53-dependent coelomocyte apoptosis by activating the p38 MAPK signaling pathway in Echinodermata.
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Affiliation(s)
- Fa Dai
- State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, China; State-Province Joint Laboratory of Marine Biotechnology and Engineering, Ningbo University, Ningbo, China
| | - Ming Guo
- State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, China; State-Province Joint Laboratory of Marine Biotechnology and Engineering, Ningbo University, Ningbo, China
| | - Yina Shao
- State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, China; State-Province Joint Laboratory of Marine Biotechnology and Engineering, Ningbo University, Ningbo, China
| | - Chenghua Li
- State Key Laboratory for Quality and Safety of Agro-products, Ningbo University, Ningbo, China; State-Province Joint Laboratory of Marine Biotechnology and Engineering, Ningbo University, Ningbo, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, PR China.
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26
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Scheithauer L, Thiem S, Ünal CM, Dellmann A, Steinert M. Zinc Metalloprotease ProA from Legionella pneumophila Inhibits the Pro-Inflammatory Host Response by Degradation of Bacterial Flagellin. Biomolecules 2022; 12:624. [PMID: 35625552 PMCID: PMC9138289 DOI: 10.3390/biom12050624] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/08/2022] [Accepted: 04/09/2022] [Indexed: 01/27/2023] Open
Abstract
The environmental bacterium Legionella pneumophila is an intracellular pathogen of various protozoan hosts and able to cause Legionnaires' disease, a severe pneumonia in humans. By encoding a wide selection of virulence factors, the infectious agent possesses several strategies to manipulate its host cells and evade immune detection. In the present study, we demonstrate that the L. pneumophila zinc metalloprotease ProA functions as a modulator of flagellin-mediated TLR5 stimulation and subsequent activation of the pro-inflammatory NF-κB pathway. We found ProA to be capable of directly degrading immunogenic FlaA monomers but not the polymeric form of bacterial flagella. These results indicate a role of the protease in antagonizing immune stimulation, which was further substantiated in HEK-BlueTM hTLR5 Detection assays. Addition of purified proteins, bacterial suspensions of L. pneumophila mutant strains as well as supernatants of human lung tissue explant infection to this reporter cell line demonstrated that ProA specifically decreases the TLR5 response via FlaA degradation. Conclusively, the zinc metalloprotease ProA serves as a powerful regulator of exogenous flagellin and presumably creates an important advantage for L. pneumophila proliferation in mammalian hosts by promoting immune evasion.
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Affiliation(s)
- Lina Scheithauer
- Institut für Mikrobiologie, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany; (L.S.); (S.T.); (C.M.Ü.)
| | - Stefanie Thiem
- Institut für Mikrobiologie, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany; (L.S.); (S.T.); (C.M.Ü.)
| | - Can M. Ünal
- Institut für Mikrobiologie, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany; (L.S.); (S.T.); (C.M.Ü.)
| | - Ansgar Dellmann
- Institut für Pathologie, Städtisches Klinikum Braunschweig, Celler Straße 38, 38114 Braunschweig, Germany;
| | - Michael Steinert
- Institut für Mikrobiologie, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany; (L.S.); (S.T.); (C.M.Ü.)
- Helmholtz Center for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
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27
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Geng S, Gu L, Zhong L, Xu T, Sun Y. Genomic organization, evolution and functional characterization of caspase-2 and caspase-8 in miiuy croaker (Miichthys miiuy). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 127:104308. [PMID: 34742824 DOI: 10.1016/j.dci.2021.104308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/02/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
As the central link and executor of cell apoptosis, the caspase protease family has received extensive attention in recent years. However, the genetic characteristics and immune functions of some caspases are still unknown in fish. In our study, we cloned the full-length caspase-2 (mmCasp2) and caspase-8 (mmCasp2) of miiuy croaker, then we analyzed characteristics and functions of these two genes which are upstream of the apoptosis cascade reaction. Mmcasp2 and mmCasp8 exhibited a conserved domain (CASc), and the different part is that the mmCasp2 has a CARD domain, while mmCasp8 have two DED domains. Sequence and evolution analysis results showed that caspase-2 is more conservative than caspae-8 in the process of evolution. Cellular localization analysis showed that the distribution of mmCasp2 and mmCasp2 was in cytoplasm. The real-time PCR analysis showed that these two caspases are constitutively expressed in different tissues, and the expression of mmCasp2 and mmCasp8 were up-regulated in the liver, spleen, and kidney after infection with V. anguillarum. Lastly, qRT-PCR and Luciferase assays analysis showed that mmCasp2 and mmCasp8 can inhibit the NF-кB pathway. In general, we systematically analyzed the structure, evolution and related functional experiments of the caspase-2 and caspase-8 in miiuy croaker, which will help further understand the role caspase family plays in the apoptosis and immune response.
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Affiliation(s)
- Shang Geng
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Liping Gu
- Department of Medical Ultrasound, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Lichang Zhong
- Department of Medical Ultrasound, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Tianjun Xu
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China; Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, Shanghai, China; National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, China
| | - Yuena Sun
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China; Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, Shanghai, China; National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, China.
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28
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Zhao BR, Wang XX, Wang XW. Shoc2 recognizes bacterial flagellin and mediates antibacterial Erk/Stat signaling in an invertebrate. PLoS Pathog 2022; 18:e1010253. [PMID: 35073369 PMCID: PMC8812994 DOI: 10.1371/journal.ppat.1010253] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 02/03/2022] [Accepted: 01/06/2022] [Indexed: 11/18/2022] Open
Abstract
Flagellin is a key bacterial virulence factor that can stimulate molecular immune signaling in both animals and plants. The detailed mechanisms of recognizing flagellin and mounting an efficient immune response have been uncovered in vertebrates; however, whether invertebrates can discriminate flagellin remains largely unknown. In the present study, the homolog of human SHOC2 leucine rich repeat scaffold protein in kuruma shrimp (Marsupenaeus japonicus), designated MjShoc2, was found to interact with Vibrio anguillarum flagellin A (FlaA) using yeast two-hybrid and pull-down assays. MjShoc2 plays a role in antibacterial response by mediating the FlaA-induced expression of certain antibacterial effectors, including lectin and antimicrobial peptide. FlaA challenge, via MjShoc2, led to phosphorylation of extracellular regulated kinase (Erk), and the subsequent activation of signal transducer and activator of transcription (Stat), ultimately inducing the expression of effectors. Therefore, by establishing the FlaA/MjShoc2/Erk/Stat signaling axis, this study revealed a new antibacterial strategy in shrimp, and provides insights into the flagellin sensing mechanism in invertebrates. Flagellin sensing has been proven as a general antibacterial strategy. Recognition of bacterial flagellin by the transmembrane receptor toll like receptor 5 (TLR5) leads to the activation of nuclear factor kappa B (NF-κB) pathway and induction of proinflammatory cytokines, while recognition by the intracellular nucleotide-binding leucine-rich (NLR) receptor leads to caspase-activation and cytokines-expression. Although flagellin is an effective immune stimulator that induces antimicrobial peptides in Drosophila and in crustaceans, how an invertebrate host senses flagellin and mounts an immune response is poorly understood. Here, we used the flagellin (FlaA) from Vibrio anguillarum, a pathogen of shrimp, as a bait protein to screen a yeast two-hybrid library derived from kuruma shrimp (Marsupenaeus japonicus). We found a scaffold protein, MjShoc2, able to interact with FlaA. We also found that FlaA could effectively induce the expression of certain recognized antibacterial effectors in shrimp depending on MjShoc2. We revealed that extracellular regulated kinase (Erk) phosphorylation occurred downstream of FlaA/MjShoc2, and led to signal transducer and activator of transcription (Stat) activation, resulting in transcription of certain effectors. Therefore our study provides new insights into the FlaA-induced molecular immunity in invertebrates.
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Affiliation(s)
- Bao-Rui Zhao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Xin-Xin Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
| | - Xian-Wei Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao, China
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- * E-mail:
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29
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Naseer N, Egan MS, Reyes Ruiz VM, Scott WP, Hunter EN, Demissie T, Rauch I, Brodsky IE, Shin S. Human NAIP/NLRC4 and NLRP3 inflammasomes detect Salmonella type III secretion system activities to restrict intracellular bacterial replication. PLoS Pathog 2022; 18:e1009718. [PMID: 35073381 PMCID: PMC8812861 DOI: 10.1371/journal.ppat.1009718] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 02/03/2022] [Accepted: 12/27/2021] [Indexed: 01/16/2023] Open
Abstract
Salmonella enterica serovar Typhimurium is a Gram-negative pathogen that uses two distinct type III secretion systems (T3SSs), termed Salmonella pathogenicity island (SPI)-1 and SPI-2, to deliver virulence factors into the host cell. The SPI-1 T3SS enables Salmonella to invade host cells, while the SPI-2 T3SS facilitates Salmonella's intracellular survival. In mice, a family of cytosolic immune sensors, including NAIP1, NAIP2, and NAIP5/6, recognizes the SPI-1 T3SS needle, inner rod, and flagellin proteins, respectively. Ligand recognition triggers assembly of the NAIP/NLRC4 inflammasome, which mediates caspase-1 activation, IL-1 family cytokine secretion, and pyroptosis of infected cells. In contrast to mice, humans encode a single NAIP that broadly recognizes all three ligands. The role of NAIP/NLRC4 or other inflammasomes during Salmonella infection of human macrophages is unclear. We find that although the NAIP/NLRC4 inflammasome is essential for detecting T3SS ligands in human macrophages, it is partially required for responses to infection, as Salmonella also activated the NLRP3 and CASP4/5 inflammasomes. Importantly, we demonstrate that combinatorial NAIP/NLRC4 and NLRP3 inflammasome activation restricts Salmonella replication in human macrophages. In contrast to SPI-1, the SPI-2 T3SS inner rod is not sensed by human or murine NAIPs, which is thought to allow Salmonella to evade host recognition and replicate intracellularly. Intriguingly, we find that human NAIP detects the SPI-2 T3SS needle protein. Critically, in the absence of both flagellin and the SPI-1 T3SS, the NAIP/NLRC4 inflammasome still controlled intracellular Salmonella burden. These findings reveal that recognition of Salmonella SPI-1 and SPI-2 T3SSs and engagement of both the NAIP/NLRC4 and NLRP3 inflammasomes control Salmonella infection in human macrophages.
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Affiliation(s)
- Nawar Naseer
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Marisa S. Egan
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Valeria M. Reyes Ruiz
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - William P. Scott
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, Oregon
| | - Emma N. Hunter
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Tabitha Demissie
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Isabella Rauch
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, Oregon
| | - Igor E. Brodsky
- Department of Pathobiology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, Pennsylvania
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
- * E-mail:
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30
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Scarfe L, Mackie GM, Maslowski KM. Inflammasome-independent functions of NAIPs and NLRs in the intestinal epithelium. Biochem Soc Trans 2021; 49:2601-2610. [PMID: 34854889 PMCID: PMC8786307 DOI: 10.1042/bst20210365] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 11/02/2021] [Accepted: 11/12/2021] [Indexed: 12/13/2022]
Abstract
The gut relies on the complex interaction between epithelial, stromal and immune cells to maintain gut health in the face of food particles and pathogens. Innate sensing by the intestinal epithelium is critical for maintaining epithelial barrier function and also orchestrating mucosal immune responses. Numerous innate pattern recognition receptors (PRRs) are involved in such sensing. In recent years, several Nucleotide-binding-domain and Leucine-rich repeat-containing receptors (NLRs) have been found to partake in pathogen or damage sensing while also being implicated in gut pathologies, such as colitis and colorectal cancer (CRC). Here, we discuss the current literature focusing on NLR family apoptosis inhibitory proteins (NAIPs) and other NLRs that have non-inflammasome roles in the gut. The mechanisms behind NLR-mediated protection often converges on similar signalling pathways, such as STAT3, MAPK and NFκB. Further understanding of how these NLRs contribute to the maintenance of gut homeostasis will be important for understanding gut pathologies and developing new therapies.
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Affiliation(s)
- Lisa Scarfe
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, U.K
| | - Gillian M. Mackie
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, U.K
| | - Kendle M. Maslowski
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, U.K
- Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, U.K
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31
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Oh C, Verma A, Hafeez M, Hogland B, Aachoui Y. Shigella OspC3 suppresses murine cytosolic LPS sensing. iScience 2021; 24:102910. [PMID: 34409271 PMCID: PMC8361271 DOI: 10.1016/j.isci.2021.102910] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/09/2021] [Accepted: 07/23/2021] [Indexed: 12/18/2022] Open
Abstract
Shigella flexneri, a cytosol-invasive gram-negative pathogen, deploys an array of type III-secreted effector proteins to evade host cell defenses. Caspase-11 and its human ortholog caspase-4 detect cytosolic lipopolysaccharide (LPS) and trigger gasdermin D-mediated pyroptosis to eliminate intra-cytoplasmic bacterial threats. However, the role of caspase-11 in combating S. flexneri is unclear. The Shigella T3SS effector OspC3 reportedly suppresses cytosolic LPS sensing by inhibiting caspase-4 but not caspase-11 activity. Surprisingly, we found that S. flexneri also uses OspC3 to inhibit murine caspase-11 activity. Mechanistically, we found that OspC3 binds only to primed caspase-11. Importantly, we demonstrate that S. flexneri employs OspC3 to prevent caspase-11-mediated pyroptosis in neutrophils, enabling bacteria to disseminate and evade clearance following intraperitoneal challenge. In contrast, S. flexneri lacking OspC3 is attenuated in a caspase-11- and gasdermin D-dependent fashion. Overall, our study reveals that OspC3 suppresses cytosolic LPS detection in a broad array of mammals. S. flexneri T3SS-secreted OspC3 suppresses cytosolic LPS sensing by caspase-11 OspC3 binds to caspase-11 in a priming-dependent manner S. flexneri employs OspC3 to prevent caspase-11-mediated pyroptosis in neutrophils Neutrophil caspase-11 is essential in defense against S. flexneri ΔOspC3 in vivo
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Affiliation(s)
- Changhoon Oh
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Ambika Verma
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Mohib Hafeez
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.,Department of Biology, University of Arkansas at Little Rock, Little Rock, AR 72204, USA
| | - Brandon Hogland
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Youssef Aachoui
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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32
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Striednig B, Lanner U, Niggli S, Katic A, Vormittag S, Brülisauer S, Hochstrasser R, Kaech A, Welin A, Flieger A, Ziegler U, Schmidt A, Hilbi H, Personnic N. Quorum sensing governs a transmissive Legionella subpopulation at the pathogen vacuole periphery. EMBO Rep 2021; 22:e52972. [PMID: 34314090 PMCID: PMC8419707 DOI: 10.15252/embr.202152972] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/01/2021] [Accepted: 07/08/2021] [Indexed: 01/24/2023] Open
Abstract
The Gram‐negative bacterium Legionella pneumophila is the causative agent of Legionnaires' disease and replicates in amoebae and macrophages within a distinct compartment, the Legionella‐containing vacuole (LCV). The facultative intracellular pathogen switches between a replicative, non‐virulent and a non‐replicating, virulent/transmissive phase. Here, we show on a single‐cell level that at late stages of infection, individual motile (PflaA‐GFP‐positive) and virulent (PralF‐ and PsidC‐GFP‐positive) L. pneumophila emerge in the cluster of non‐growing bacteria within an LCV. Comparative proteomics of PflaA‐GFP‐positive and PflaA‐GFP‐negative L. pneumophila subpopulations reveals distinct proteomes with flagellar proteins or cell division proteins being preferentially produced by the former or the latter, respectively. Toward the end of an infection cycle (˜ 48 h), the PflaA‐GFP‐positive L. pneumophila subpopulation emerges at the cluster periphery, predominantly escapes the LCV, and spreads from the bursting host cell. These processes are mediated by the Legionella quorum sensing (Lqs) system. Thus, quorum sensing regulates the emergence of a subpopulation of transmissive L. pneumophila at the LCV periphery, and phenotypic heterogeneity underlies the intravacuolar bi‐phasic life cycle of L. pneumophila.
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Affiliation(s)
- Bianca Striednig
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Ulrike Lanner
- Proteomics Core Facility, Biozentrum, University of Basel, Basel, Switzerland
| | - Selina Niggli
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Ana Katic
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Simone Vormittag
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Sabrina Brülisauer
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Ramon Hochstrasser
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Andres Kaech
- Center for Microscopy and Image Analysis, University of Zürich, Zürich, Switzerland
| | - Amanda Welin
- Division of Inflammation and Infection, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Antje Flieger
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institute, Wernigerode, Germany
| | - Urs Ziegler
- Center for Microscopy and Image Analysis, University of Zürich, Zürich, Switzerland
| | - Alexander Schmidt
- Proteomics Core Facility, Biozentrum, University of Basel, Basel, Switzerland
| | - Hubert Hilbi
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
| | - Nicolas Personnic
- Institute of Medical Microbiology, University of Zürich, Zürich, Switzerland
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33
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Wong AO, Marthi M, Haag A, Owusu IA, Wobus CE, Swanson JA. Macrophage inflammatory state influences susceptibility to lysosomal damage. J Leukoc Biol 2021; 111:629-639. [PMID: 34259355 PMCID: PMC8758784 DOI: 10.1002/jlb.3a0520-325rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Macrophages possess mechanisms for reinforcing the integrity of their endolysosomes against damage. This property, termed inducible renitence, was previously observed in murine macrophages stimulated with LPS, peptidoglycan, IFNγ, or TNFα, which suggested roles for renitence in macrophage resistance to infection by membrane‐damaging pathogens. This study analyzed additional inducers of macrophage differentiation for their ability to increase resistance to lysosomal damage by membrane‐damaging particles. Renitence was evident in macrophages activated with LPS plus IFNγ, PGE2, or adenosine, and in macrophages stimulated with IFN‐β, but not in macrophages activated with IL‐4 or IL‐10. These responses indicated roles for macrophage subtypes specialized in host defense and suppression of immune responses, but not those involved in wound healing. Consistent with this pattern, renitence could be induced by stimulation with agonists for TLR, which required the signaling adaptors MyD88 and/or TRIF, and by infection with murine norovirus‐1. Renitence induced by LPS was dependent on cytokine secretion by macrophages. However, no single secreted factor could explain all the induced responses. Renitence induced by the TLR3 agonist Poly(I:C) was mediated in part by the type I IFN response, but renitence induced by Pam3CSK4 (TLR2/1), LPS (TLR4), IFNγ, or TNFα was independent of type 1 IFN signaling. Thus, multiple pathways for inducing macrophage resistance to membrane damage exist and depend on the particular microbial stimulus sensed.
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Affiliation(s)
- Amanda O Wong
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,University of Michigan Medical School, Ann Arbor, MI, USA
| | - Matangi Marthi
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Amanda Haag
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Irene A Owusu
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,West African Center for Cell Biology of Infectious Pathogens, University of Ghana, Legon, Ghana
| | - Christiane E Wobus
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,University of Michigan Medical School, Ann Arbor, MI, USA
| | - Joel A Swanson
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA.,University of Michigan Medical School, Ann Arbor, MI, USA
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34
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Dhital S, Deo P, Stuart I, Naderer T. Bacterial outer membrane vesicles and host cell death signaling. Trends Microbiol 2021; 29:1106-1116. [PMID: 34001418 DOI: 10.1016/j.tim.2021.04.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 12/16/2022]
Abstract
The programmed cell death pathways of pyroptosis and apoptosis protect mammals from infections. The activation of host cell death signaling depends on cell surface and cytosolic receptors that bind bacterial molecules or sense their activity. The formation of cytosolic protein complexes, such as the inflammasome and apoptosome, activates caspases, pore-forming proteins, and inflammatory cytokines. These pathways respond to bacteria and their released membrane vesicles. Outer membrane vesicles (OMVs) that emerge from the outer membrane of Gram-negative bacteria deliver a range of bacterial molecules, including lipids, proteins, polysaccharides and nucleic acids to host cells. Recent findings describe how OMV-associated molecules activate pyroptosis, apoptosis, and other inflammatory pathways. We discuss here how OMV-associated molecules are sensed by the immune system and how this contributes to infections and inflammatory diseases.
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Affiliation(s)
- Subhash Dhital
- Department of Biochemistry & Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton 3800, Australia
| | - Pankaj Deo
- Department of Biochemistry & Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton 3800, Australia
| | - Isabella Stuart
- Department of Biochemistry & Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton 3800, Australia
| | - Thomas Naderer
- Department of Biochemistry & Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton 3800, Australia.
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Kovacs SB, Oh C, Maltez VI, McGlaughon BD, Verma A, Miao EA, Aachoui Y. Neutrophil Caspase-11 Is Essential to Defend against a Cytosol-Invasive Bacterium. Cell Rep 2021; 32:107967. [PMID: 32726630 PMCID: PMC7480168 DOI: 10.1016/j.celrep.2020.107967] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/16/2020] [Accepted: 07/08/2020] [Indexed: 12/20/2022] Open
Abstract
Either caspase-1 or caspase-11 can cleave gasdermin D to cause pyroptosis, eliminating intracellular replication niches. We previously showed that macrophages detect Burkholderia thailandensis via NLRC4, triggering the release of interleukin (IL)-18 and driving an essential interferon (IFN)-γ response that primes caspase-11. We now identify the IFN-γ-producing cells as a mixture of natural killer (NK) and T cells. Although both caspase-1 and caspase-11 can cleave gasdermin D in macrophages and neutrophils, we find that NLRC4-activated caspase-1 triggers pyroptosis in macrophages, but this pathway does not trigger pyroptosis in neutrophils. In contrast, caspase-11 triggers pyroptosis in both macrophages and neutrophils. This translates to an absolute requirement for caspase-11 in neutrophils during B. thailandensis infection in mice. We present an example of inflammasome sensors causing diverging outcomes in different cell types. Thus, cell fates are dictated not simply by the pathogen or inflammasome, but also by how the cell is wired to respond to detection events. Kovacs et al. demonstrate that natural killer and T cells produce IFN-γ to prime caspase-11 during Burkholderia thailandensis infection. They demonstrate that in neutrophils, caspase-1 and caspase-11 activation lead to gasdermin D cleavage, but only caspase-11 activation leads to pyroptosis that is necessary for clearance of this cytosol-invasive pathogen in vivo.
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Affiliation(s)
- Stephen B Kovacs
- Department of Immunology, Duke University, Durham, NC 27710, USA; Department of Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA; Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Changhoon Oh
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Vivien I Maltez
- Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Benjamin D McGlaughon
- Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ambika Verma
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Edward A Miao
- Department of Immunology, Duke University, Durham, NC 27710, USA; Department of Molecular Genetics and Microbiology, Duke University, Durham, NC 27710, USA; Department of Microbiology and Immunology, Center for Gastrointestinal Biology and Disease, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Youssef Aachoui
- Department of Microbiology and Immunology, Center for Microbial Pathogenesis and Host Responses, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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36
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Chauhan D, Shames SR. Pathogenicity and Virulence of Legionella: Intracellular replication and host response. Virulence 2021; 12:1122-1144. [PMID: 33843434 PMCID: PMC8043192 DOI: 10.1080/21505594.2021.1903199] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Bacteria of the genus Legionella are natural pathogens of amoebae that can cause a severe pneumonia in humans called Legionnaires’ Disease. Human disease results from inhalation of Legionella-contaminated aerosols and subsequent bacterial replication within alveolar macrophages. Legionella pathogenicity in humans has resulted from extensive co-evolution with diverse genera of amoebae. To replicate intracellularly, Legionella generates a replication-permissive compartment called the Legionella-containing vacuole (LCV) through the concerted action of hundreds of Dot/Icm-translocated effector proteins. In this review, we present a collective overview of Legionella pathogenicity including infection mechanisms, secretion systems, and translocated effector function. We also discuss innate and adaptive immune responses to L. pneumophila, the implications of Legionella genome diversity and future avenues for the field.
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Affiliation(s)
- Deepika Chauhan
- Division of Biology, Kansas State University, Manhattan, Kansas, USA
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37
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Liu X, Boyer MA, Holmgren AM, Shin S. Legionella-Infected Macrophages Engage the Alveolar Epithelium to Metabolically Reprogram Myeloid Cells and Promote Antibacterial Inflammation. Cell Host Microbe 2020; 28:683-698.e6. [PMID: 32841604 DOI: 10.1016/j.chom.2020.07.019] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/18/2020] [Accepted: 07/27/2020] [Indexed: 01/05/2023]
Abstract
Alveolar macrophages are among the first immune cells that respond to inhaled pathogens. However, numerous pathogens block macrophage-intrinsic immune responses, making it unclear how robust antimicrobial responses are generated. The intracellular bacterium Legionella pneumophila inhibits host translation, thereby impairing cytokine production by infected macrophages. Nevertheless, Legionella-infected macrophages induce an interleukin-1 (IL-1)-dependent inflammatory cytokine response by recruited monocytes and other cells that controls infection. How IL-1 directs these cells to produce inflammatory cytokines is unknown. Here, we show that collaboration with the alveolar epithelium is critical for controlling infection. IL-1 induces the alveolar epithelium to produce granulocyte-macrophage colony-stimulating factor (GM-CSF). Intriguingly, GM-CSF signaling amplifies inflammatory cytokine production in recruited monocytes by enhancing Toll-like receptor (TLR)-induced glycolysis. Our findings reveal that alveolar macrophages engage alveolar epithelial signals to metabolically reprogram monocytes for antibacterial inflammation.
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Affiliation(s)
- Xin Liu
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mark A Boyer
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alicia M Holmgren
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sunny Shin
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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38
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Mehdi Abdol M, Mohabati Mobarez A, Khoramabadi N, Papian S, Talebi Bezmin Abadi A. Potent T-cell mediated immune response against Legionella pneumophila in mice following vaccination with detoxified lipopolysaccharide non-covalently combined with recombinant flagellin A and peptidoglycan-associated lipoprotein. Microb Pathog 2020; 149:104364. [PMID: 32771655 DOI: 10.1016/j.micpath.2020.104364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 05/28/2020] [Accepted: 06/25/2020] [Indexed: 11/26/2022]
Abstract
BACKGROUND Legionella pneumophila is a Gram-negative intracellular bacterium and the cause of an atypical pneumonia in humans - legionnaire's disease. Immunological assessment of bacterial antigens clarifies the way that host may develop protection against the pathogen. Lipopolysaccharide (LPS) is the main antigen of Gram-negative bacteria but is less studied because of its carbohydrate nature. Here, we immunized mice with detoxified LPS in combination with immunogenic proteins and looked into the result of bacterial challenge. METHODS LPS of L. pneumophila was extracted by hot phenol-water method. Purified LPS was detoxified by sodium hydroxide alkaline procedure. BALB/c mice were immunized mainly with non-covalent combination of detoxified LPS (dLPS) and either of recombinant FlaA or PAL separately. Afterwards, specific serum IgG was assessed by ELISA. Mice were challenged intravenously with sublethal dose of L. pneumpphila then splenocytes were cultured. Cytokine responses of splenocytes were analyzed by ELISA. RESULTS Polysaccharide antigen did not elicit significant serum IgG. Combination of the dLPS with recombinant FlaA and PAL led to risen IgG and its subclasses (IgG1, IgG2a and IgG2b) against polysaccharide. Mice immunized with combination of the dLPS and recombinant proteins showed significant elevation of cytokine responses in splenocyte culture after being challenged with L. pneumophila. CONCLUSIONS Our results suggest that combination of polysaccharide antigen derived from Legionella LPS may confer raised cell-mediated responses against the pathogen when combined with Th-1 stimulating protein antigens. Although not covalently bond, Legionella detoxified LPS combination with recombinant FlaA and PAL effectively elicited Th-1 type cytokines and humoral responses against L. pneumophila in BALB/c mice.
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Affiliation(s)
- Mohsen Mehdi Abdol
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Ashraf Mohabati Mobarez
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Nima Khoramabadi
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Shaghayegh Papian
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Amin Talebi Bezmin Abadi
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
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39
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Andrade WA, Zamboni DS. NLRC4 biology in immunity and inflammation. J Leukoc Biol 2020; 108:1117-1127. [PMID: 32531834 DOI: 10.1002/jlb.3mr0420-573r] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/29/2020] [Accepted: 05/05/2020] [Indexed: 12/14/2022] Open
Abstract
Inflammasomes are cytosolic multiprotein complexes that sense microbial infections or host cell damage, triggering cytokine production and a proinflammatory form of cell death, called pyroptosis. Whereas pyroptosis and cytokine production may often promote host resistance to infections, uncontrolled inflammasome activation leads to autoinflammatory diseases in humans. Among the multiple inflammasomes described, the neuronal apoptosis inhibitory protein/nucleotide-binding domain leucine-rich repeat-containing protein family caspase activation and recruitment domain-containing protein 4 (NLRC4) inflammasome emerged as a critical component for the restriction of bacterial infections. Accordingly, our understanding of this inflammasome advanced remarkably over the last 10 yr, expanding our knowledge about ligand-receptor interaction; cryo-EM structure; and downstream effectors and substrates, such as gasdermin-D, caspase-1, caspase-8, and caspase-7. In this review, we discuss recent advances on the biology of the NLRC4 inflammasome, in terms of structure and activation mechanisms, importance in bacterial and nonbacterial diseases, and the identification of NLRC4 gain-of-function mutations leading to NLRC4-associated autoinflammatory diseases in humans.
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Affiliation(s)
- Warrison A Andrade
- Department of Cell Biology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil
| | - Dario S Zamboni
- Department of Cell Biology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Ribeirão Preto, São Paulo, Brazil
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40
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Bauer R, Rauch I. The NAIP/NLRC4 inflammasome in infection and pathology. Mol Aspects Med 2020; 76:100863. [PMID: 32499055 DOI: 10.1016/j.mam.2020.100863] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 04/30/2020] [Indexed: 12/16/2022]
Abstract
In this review we give an overview of the NAIP/NLRC4 activation mechanism as well as the described roles of this inflammasome, with a focus on in vivo infection and pathology. After ligand recognition by NAIP sensor proteins the NAIP/NLRC4 inflammasome forms through oligomerization with the NLRC4 adaptor to activate Caspase-1. The activating ligands are intracellular bacterial flagellin or type-3 secretion system components, delivered by pathogens. In vivo experiments indicate a role in macrophages during lung, spleen and liver infection and systemic sepsis like conditions, as well as in intestinal epithelial cells. Upon NAIP/NLRC4 activation in the intestine, epithelial cell extrusion is triggered in addition to the canonical inflammasome outcomes of cytokine cleavage and pyroptosis. Human patients with auto-activating mutations in NLRC4 present with an autoinflammatory syndrome including enterocolitis. Although one of the better understood inflammasomes in terms of mechanism, tissue specific functions of NAIP/NLRC4 are only beginning to be understood.
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Affiliation(s)
- Renate Bauer
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA; Department of Biosciences, University of Salzburg, A-5020, Salzburg, Austria
| | - Isabella Rauch
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, OR, USA.
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41
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Al Mamun A, Wu Y, Jia C, Munir F, Sathy KJ, Sarker T, Monalisa I, Zhou K, Xiao J. Role of pyroptosis in liver diseases. Int Immunopharmacol 2020; 84:106489. [PMID: 32304992 DOI: 10.1016/j.intimp.2020.106489] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/03/2020] [Accepted: 04/05/2020] [Indexed: 12/17/2022]
Abstract
Pyroptosis is known as a novel form of pro-inflammatory cell death program, which is exceptional from other types of cell death programs. Particularly, pyroptosis is characterized by Gasdermin family-mediated pore formation and subsequently cellular lysis, also release of several pro-inflammatory intracellular cytokines. In terms of mechanism, there are two signaling pathways involved in pyroptosis, including caspase-1, and caspase-4/5/11 mediated pathways. However, pyroptosis plays important roles in immune defense mechanisms. Recent studies have demonstrated that pyroptosis plays significant roles in the development of liver diseases. In our review, we have focused on the role of pyroptosis based on the molecular and pathophysiological mechanisms in the development of liver diseases. We have also highlighted targeting of pyroptosis for the therapeutic implications in liver diseases in the near future.
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Affiliation(s)
- Abdullah Al Mamun
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, Zhejiang Province, China
| | - Yanqing Wu
- Institute of Life Sciences, Wenzhou University, Wenzhou 325035, Zhejiang Province, China
| | - Chang Jia
- Pediatric Research Institute, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang Province, China
| | - Fahad Munir
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Kasfia Jahan Sathy
- Department of Pharmacy, North South University, Bashundhara, Dhaka 1229, Bangladesh
| | - Tamanna Sarker
- Department of Pharmacy, Southeast University, Banani, Dhaka 1213, Bangladesh
| | - Ilma Monalisa
- Department of Pharmacy, Southeast University, Banani, Dhaka 1213, Bangladesh
| | - Kailiang Zhou
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, Zhejiang Province, China
| | - Jian Xiao
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, Zhejiang Province, China.
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42
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Gilchrist AK, Smolensky D, Ngwaga T, Chauhan D, Cox S, Perumal R, Noronha LE, Shames SR. High-polyphenol extracts from Sorghum bicolor attenuate replication of Legionella pneumophila within RAW 264.7 macrophages. FEMS Microbiol Lett 2020; 367:fnaa053. [PMID: 32188994 PMCID: PMC8023677 DOI: 10.1093/femsle/fnaa053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 03/17/2020] [Indexed: 12/12/2022] Open
Abstract
Polyphenols derived from a variety of plants have demonstrated antimicrobial activity against diverse microbial pathogens. Legionella pneumophila is an intracellular bacterial pathogen that opportunistically causes a severe inflammatory pneumonia in humans, called Legionnaires' Disease, via replication within macrophages. Previous studies demonstrated that tea polyphenols attenuate L. pneumophila intracellular replication within mouse macrophages via increased tumor necrosis factor (TNF) production. Sorghum bicolor is a sustainable cereal crop that thrives in arid environments and is well-suited to continued production in warming climates. Sorghum polyphenols have anticancer and antioxidant properties, but their antimicrobial activity has not been evaluated. Here, we investigated the impact of sorghum polyphenols on L. pneumophila intracellular replication within RAW 264.7 mouse macrophages. Sorghum high-polyphenol extract (HPE) attenuated L. pneumophila intracellular replication in a dose-dependent manner but did not impair either bacterial replication in rich media or macrophage viability. Moreover, HPE treatment enhanced both TNF and IL-6 secretion from L. pneumophila infected macrophages. Thus, polyphenols derived from sorghum enhance macrophage restriction of L. pneumophila, likely via increased pro-inflammatory cytokine production. This work reveals commonalities between plant polyphenol-mediated antimicrobial activity and provides a foundation for future evaluation of sorghum as an antimicrobial agent.
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Affiliation(s)
- Aubrey K Gilchrist
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, Kansas, 66506 USA
| | - Dmitriy Smolensky
- Grain Quality and Structure Research Unit, Agricultural Research Service, U.S. Department of Agriculture, 1515 College Avenue, Manhattan, Kansas, 66506 USA
| | - Tshegofatso Ngwaga
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, Kansas, 66506 USA
| | - Deepika Chauhan
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, Kansas, 66506 USA
| | - Sarah Cox
- Grain Quality and Structure Research Unit, Agricultural Research Service, U.S. Department of Agriculture, 1515 College Avenue, Manhattan, Kansas, 66506 USA
| | - Ramasamy Perumal
- Kansas State University Agricultural Research Center, 1232 240th Avenue, Hays, Kansas, 67601 USA
| | - Leela E Noronha
- Arthropod-borne Animal Disease Research Unit, Agricultural Research Service, U. S. Department of Agriculture, 1515 College Avenue, Manhattan, Kansas, 66506 USA
| | - Stephanie R Shames
- Division of Biology, Kansas State University, 1717 Claflin Road, Manhattan, Kansas, 66506 USA
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IRG1 and Inducible Nitric Oxide Synthase Act Redundantly with Other Interferon-Gamma-Induced Factors To Restrict Intracellular Replication of Legionella pneumophila. mBio 2019; 10:mBio.02629-19. [PMID: 31719183 PMCID: PMC6851286 DOI: 10.1128/mbio.02629-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Legionella pneumophila is one example among many species of pathogenic bacteria that replicate within mammalian macrophages during infection. The immune signaling factor interferon gamma (IFN-γ) blocks L. pneumophila replication in macrophages and is an essential component of the immune response to L. pneumophila and other intracellular pathogens. However, to date, no study has identified the exact molecular factors induced by IFN-γ that are required for its activity. We generated macrophages lacking different combinations of IFN-γ-induced genes in an attempt to find a genetic background in which there is a complete loss of IFN-γ-mediated restriction of L. pneumophila. We identified six genes that comprise the totality of the IFN-γ-dependent restriction of L. pneumophila replication in macrophages. Our results clarify the molecular basis underlying the potent effects of IFN-γ and highlight how redundancy downstream of IFN-γ is key to prevent exploitation of macrophages by pathogens. Interferon gamma (IFN-γ) restricts the intracellular replication of many pathogens, but the mechanism by which IFN-γ confers cell-intrinsic pathogen resistance remains unclear. For example, intracellular replication of the bacterial pathogen Legionella pneumophila in macrophages is potently curtailed by IFN-γ. However, consistent with prior studies, no individual genetic deficiency that we tested completely abolished IFN-γ-mediated control. Intriguingly, we observed that the glycolysis inhibitor 2-deoxyglucose (2DG) partially rescued L. pneumophila replication in IFN-γ-treated macrophages. 2DG inhibits glycolysis and triggers the unfolded protein response, but unexpectedly, it appears these effects are not responsible for perturbing the antimicrobial activity of IFN-γ. Instead, we found that 2DG rescues bacterial replication by inhibiting the expression of two key antimicrobial factors, inducible nitric oxide synthase (iNOS) and immune-responsive gene 1 (IRG1). Using immortalized and primary macrophages deficient in iNOS and IRG1, we confirmed that loss of both iNOS and IRG1, but not individual deficiency in either gene, partially reduced IFN-γ-mediated restriction of L. pneumophila. Further, using a combinatorial CRISPR/Cas9 mutagenesis approach, we found that mutation of iNOS and IRG1 in combination with four other genes (CASP11, IRGM1, IRGM3, and NOX2) resulted in a total loss of L. pneumophila restriction by IFN-γ in primary bone marrow macrophages. Our study defines a complete set of cell-intrinsic factors required for IFN-γ-mediated restriction of an intracellular bacterial pathogen and highlights the combinatorial strategy used by hosts to block bacterial replication in macrophages.
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Shah JA, Emery R, Lee B, Venkatasubramanian S, Simmons JD, Brown M, Hung CF, Prins JM, Verbon A, Hawn TR, Skerrett SJ. TOLLIP deficiency is associated with increased resistance to Legionella pneumophila pneumonia. Mucosal Immunol 2019; 12:1382-1390. [PMID: 31462698 PMCID: PMC6824992 DOI: 10.1038/s41385-019-0196-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 07/08/2019] [Accepted: 08/02/2019] [Indexed: 02/04/2023]
Abstract
Legionella pneumophila (Lp) is a flagellated, intracellular bacterium that can cause Legionnaires' disease (LD). Lp activates multiple innate immune receptors, and TOLLIP dampens MyD88-dependent signaling and may influence susceptibility to LD. We evaluated the effect of TOLLIP on innate immunity, pneumonia severity, and LD susceptibility in mouse lungs and human populations. To accomplish this, we evaluated the effect of TOLLIP on lung-specific Lp control and immune response and associated a common functional TOLLIP variant with Lp-induced innate immune responses and LD susceptibility in humans. After aerosol Lp infection, Tollip-/- mice demonstrated significantly fewer bacterial colony-forming unit and increased cytokine responses from BAL fluid. Tollip-/- macrophages also suppressed intracellular Lp replication in a flagellin-independent manner. The presence of a previously characterized, functionally active SNP associated with decreased TOLLIP mRNA transcript in monocytes was associated with increased TNF and IL-6 secretion after Lp stimulation of PBMC ex vivo. This genotype was separately associated with decreased LD susceptibility (309 controls, 88 cases, p = 0.008, OR 0.36, 95% CI 0.16-0.76) in a candidate gene association study. These results suggest that TOLLIP decreases lung-specific TLR responses to increase LD susceptibility in human populations. Better understanding of TOLLIP may lead to novel immunomodulatory therapies.
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Affiliation(s)
- Javeed A. Shah
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington.,Veterans Affairs Puget Sound Health Care System, Seattle, Washington
| | - Robyn Emery
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Brian Lee
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | | | - Jason D. Simmons
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Melanie Brown
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Chi F. Hung
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Jan M. Prins
- University of Amsterdam, Amsterdam, the Netherlands
| | | | - Thomas R. Hawn
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Shawn J. Skerrett
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington
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45
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Toll-like receptor ligands and their combinations as adjuvants - current research and its relevance in chickens. WORLD POULTRY SCI J 2019. [DOI: 10.1017/s0043933915000094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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46
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Ketelut-Carneiro N, Souza COS, Benevides L, Gardinassi LG, Silva MC, Tavares LA, Zamboni DS, Silva JS. Caspase-11-dependent IL-1α release boosts Th17 immunity against Paracoccidioides brasiliensis. PLoS Pathog 2019; 15:e1007990. [PMID: 31425553 PMCID: PMC6715237 DOI: 10.1371/journal.ppat.1007990] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 08/29/2019] [Accepted: 07/18/2019] [Indexed: 12/22/2022] Open
Abstract
The granulomatous lesion resulting from infection with the fungus Paracoccidioides brasiliensis is characterized by a compact aggregate of mature cells, surrounded by a fibroblast- and collagen-rich content. Granuloma formation requires signaling elicited by inflammatory molecules such as members of the interleukin-1 family. Two members of this family have been thoroughly studied, namely IL-1α and IL-1β. In this study, we addressed the mechanisms underlying IL-1α secretion and its functional role on the host resistance to fungal infection. We found that, the expression of caspase-11 triggered by P. brasiliensis infection of macrophages depends on IFN-β production, because its inhibition reduced procaspase-11 levels. Curiously, caspase-11 deficiency did not impair IL-1β production, however caspase-11 was required for a rapid pore-mediated cell lysis. The plasma membrane rupture facilitated the release of IL-1α, which was necessary to induce NO production and restrict fungal replication. Furthermore, P. brasiliensis-infected macrophages required IL-1α to produce optimal levels of IL-6, a major component of Th17 lymphocyte differentiation. Indeed, IL-1α deficiency accounted for a significant reduction of Th17 lymphocytes in lungs of infected mice, correlating with diminished neutrophil infiltration in the lungs. Strikingly, we identified that IL-1α directly reprograms the transcriptional profile of Th17-committed lymphocytes, increasing cellular proliferation, as for boosting IL-17 production by these cells. Beyond neutrophil chemotaxis in vivo, IL-17 also amplified IL-1α production by infected macrophages in vitro, endorsing a critical amplification loop of the inflammatory response. Therefore, our data suggest that the IFN-β/caspase-11/IL-1α pathway shapes a protective antifungal Th17 immunity, revealing a molecular mechanism underlying the cross-talk between innate and adaptive immunity.
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Affiliation(s)
- Natália Ketelut-Carneiro
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Camila Oliveira Silva Souza
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luciana Benevides
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luiz Gustavo Gardinassi
- Department of Clinical Analyses, Toxicology and Food Science, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Maria Cláudia Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Lucas Alves Tavares
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Dario Simões Zamboni
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - João Santana Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
- Fiocruz-Bi-Institutional Translational Medicine Project, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
- * E-mail:
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47
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Gonçalves AV, Margolis SR, Quirino GFS, Mascarenhas DPA, Rauch I, Nichols RD, Ansaldo E, Fontana MF, Vance RE, Zamboni DS. Gasdermin-D and Caspase-7 are the key Caspase-1/8 substrates downstream of the NAIP5/NLRC4 inflammasome required for restriction of Legionella pneumophila. PLoS Pathog 2019; 15:e1007886. [PMID: 31251782 PMCID: PMC6622555 DOI: 10.1371/journal.ppat.1007886] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 07/11/2019] [Accepted: 06/03/2019] [Indexed: 11/24/2022] Open
Abstract
Inflammasomes are cytosolic multi-protein complexes that detect infection or cellular damage and activate the Caspase-1 (CASP1) protease. The NAIP5/NLRC4 inflammasome detects bacterial flagellin and is essential for resistance to the flagellated intracellular bacterium Legionella pneumophila. The effectors required downstream of NAIP5/NLRC4 to restrict bacterial replication remain unclear. Upon NAIP5/NLRC4 activation, CASP1 cleaves and activates the pore-forming protein Gasdermin-D (GSDMD) and the effector caspase-7 (CASP7). However, Casp1–/– (and Casp1/11–/–) mice are only partially susceptible to L. pneumophila and do not phenocopy Nlrc4–/–mice, because NAIP5/NLRC4 also activates CASP8 for restriction of L. pneumophila infection. Here we show that CASP8 promotes the activation of CASP7 and that Casp7/1/11–/– and Casp8/1/11–/– mice recapitulate the full susceptibility of Nlrc4–/– mice. Gsdmd–/– mice exhibit only mild susceptibility to L. pneumophila, but Gsdmd–/–Casp7–/– mice are as susceptible as the Nlrc4–/– mice. These results demonstrate that GSDMD and CASP7 are the key substrates downstream of NAIP5/NLRC4/CASP1/8 required for resistance to L. pneumophila. Inflammasomes are multi-protein complexes that detect infection and other stimuli and activate the Caspase-1 (CASP1) protease. The effectors required downstream of NAIP5/NLRC4 to restrict bacterial replication remain unclear. Active CASP1 cleaves and activates the pore-forming protein gasdermin D (GSDMD) to induce inflammation and cell death. We have previously shown that CASP8 is activated by the NAIP5/NLRC4 inflammasome independently of CASP1 and functions to restrict replication of the intracellular bacterium Legionella pneumophila. Here, we show that CASP7 is activated downstream of CASP8 and is required for CASP8-dependent restriction of L. pneumophila replication in macrophages and in vivo. In addition, CASP7 is also activated by CASP1. Taken together, these results imply that CASP7 and GSDMD are the two key caspase substrates downstream of NAIP5/NLRC4. In support of this hypothesis, we found that mice double deficient in CASP7 and GSDMD are more susceptible than the single knockouts and are as susceptible as the Nlrc4 deficient mice for restriction of L. pneumophila replication in vivo. Collectively, our data indicate that GSDMD and CASP7 are activated by CASP1 and induce cell death and restriction of bacterial infection. Therefore, GSDMD and multiple caspases (CASP1, CASP7 and CASP8) operate downstream of the NAIP5/NLRC4 inflammasome for restriction of infection by pathogenic bacteria.
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Affiliation(s)
- Augusto V. Gonçalves
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Shally R. Margolis
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, and Cancer Research Laboratory, University of California, Berkeley, California, United States of America
| | - Gustavo F. S. Quirino
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Danielle P. A. Mascarenhas
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Isabella Rauch
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, and Cancer Research Laboratory, University of California, Berkeley, California, United States of America
| | - Randilea D. Nichols
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, and Cancer Research Laboratory, University of California, Berkeley, California, United States of America
| | - Eduard Ansaldo
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, and Cancer Research Laboratory, University of California, Berkeley, California, United States of America
| | - Mary F. Fontana
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, and Cancer Research Laboratory, University of California, Berkeley, California, United States of America
| | - Russell E. Vance
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, and Cancer Research Laboratory, University of California, Berkeley, California, United States of America
- Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
- * E-mail: (REV); (DSZ)
| | - Dario S. Zamboni
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
- * E-mail: (REV); (DSZ)
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48
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Potentiation of Cytokine-Mediated Restriction of Legionella Intracellular Replication by a Dot/Icm-Translocated Effector. J Bacteriol 2019; 201:JB.00755-18. [PMID: 31036725 DOI: 10.1128/jb.00755-18] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 04/22/2019] [Indexed: 01/23/2023] Open
Abstract
Legionella pneumophila is ubiquitous in freshwater environments, where it replicates within unicellular protozoa. However, L. pneumophila is also an accidental human pathogen that can cause Legionnaires' disease in immunocompromised individuals by uncontrolled replication within alveolar macrophages. To replicate within eukaryotic phagocytes, L. pneumophila utilizes a Dot/Icm type IV secretion system to translocate a large arsenal of over 300 effector proteins directly into host cells. In mammals, translocated effectors contribute to innate immune restriction of L. pneumophila We found previously that the effector LegC4 is important for L. pneumophila replication within a natural host protist but is deleterious to replication in a mouse model of Legionnaires' disease. In the present study, we used cultured mouse primary macrophages to investigate how LegC4 attenuates L. pneumophila replication. We found that LegC4 enhanced restriction of L. pneumophila replication within macrophages activated with tumor necrosis factor (TNF) or interferon gamma (IFN-γ). In addition, expression of legC4 was sufficient to restrict Legionella longbeachae replication within TNF- or IFN-γ-activated macrophages. Thus, this study demonstrates that LegC4 contributes to L. pneumophila clearance from healthy hosts by potentiating cytokine-mediated host defense mechanisms.IMPORTANCE Legionella spp. are natural pathogens of protozoa and accidental pathogens of humans. Innate immunity in healthy individuals effectively controls Legionella infection due in part to rapid and robust production of proinflammatory cytokines resulting from detection of Dot/Icm-translocated substrates, including effectors. Here, we demonstrate that the effector LegC4 enhances proinflammatory host restriction of Legionella by macrophages. These data suggest that LegC4 may augment proinflammatory signaling or antimicrobial activity of macrophages, a function that has not previously been observed for another bacterial effector. Further insight into LegC4 function will likely reveal novel mechanisms to enhance immunity against pathogens.
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Fusco WG, Duncan JA. Novel aspects of the assembly and activation of inflammasomes with focus on the NLRC4 inflammasome. Int Immunol 2019; 30:183-193. [PMID: 29617808 DOI: 10.1093/intimm/dxy009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 02/13/2018] [Indexed: 12/31/2022] Open
Abstract
Inflammasomes are multiprotein structures that activate caspase-1, support secretion of pro-inflammatory cytokines, IL-1β and IL-18, and also induce inflammatory programmed cell death, termed pyoptosis. Inflammasomes are activated in response to the detection of endogenous and microbially derived danger signals and are mediated by several classes of inflammasome-forming sensors. These include several nucleotide-binding proteins of the NOD-like receptor (NLR) family, including NLRP1, NLRP3 and NLRC4, as well as the proteins Absent in Melanoma 2 (AIM2) and Pyrin. Mutations in genes encoding some of these sensors have been found to be associated with gain-of-function monogenetic inflammatory disorders in humans. Genetic, biochemical and structural studies have begun to demonstrate how these proteins sense danger signals and to shed light on the step-by-step processes that are necessary for the assembly of inflammasomes, in both physiologic responses to pathogens and potentially in autoinflammatory conditions. Recent biochemical studies of pro-caspase-1 and an adapter protein known as ASC suggest that inflammasomes act to initiate self-generating effector filaments responsible for activating caspase-1 and initiating downstream signaling. These studies have suggested a model of molecular events from sensor activation to inflammasome formation that may describe processes that are universal to inflammasome formation.
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Affiliation(s)
- William G Fusco
- Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Joseph A Duncan
- Department of Medicine, Division of Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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50
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Leishmania donovani evades Caspase 1 dependent host defense mechanism during infection. Int J Biol Macromol 2019; 126:392-401. [DOI: 10.1016/j.ijbiomac.2018.12.185] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 12/08/2018] [Accepted: 12/21/2018] [Indexed: 01/31/2023]
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