1
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Tucker JS, Khan H, D’Orazio SEF. Lymph node stromal cells vary in susceptibility to infection but can support the intracellular growth of Listeria monocytogenes. J Leukoc Biol 2024; 116:132-145. [PMID: 38416405 PMCID: PMC11212796 DOI: 10.1093/jleuko/qiae040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/26/2024] [Accepted: 02/13/2024] [Indexed: 02/29/2024] Open
Abstract
Lymph node stromal cells (LNSCs) are an often overlooked component of the immune system but play a crucial role in maintaining tissue homeostasis and orchestrating immune responses. Our understanding of the functions these cells serve in the context of bacterial infections remains limited. We previously showed that Listeria monocytogenes, a facultative intracellular foodborne bacterial pathogen, must replicate within an as-yet-unidentified cell type in the mesenteric lymph node (MLN) to spread systemically. Here, we show that L. monocytogenes could invade, escape from the vacuole, replicate exponentially, and induce a type I interferon response in the cytosol of 2 LNSC populations infected in vitro, fibroblastic reticular cells (FRCs) and blood endothelial cells (BECs). Infected FRCs and BECs also produced a significant chemokine and proinflammatory cytokine response after in vitro infection. Flow cytometric analysis confirmed that GFP+ L. monocytogenes were associated with a small percentage of MLN stromal cells in vivo following foodborne infection of mice. Using fluorescent microscopy, we showed that these cell-associated bacteria were intracellular L. monocytogenes and that the number of infected FRCs and BECs changed over the course of a 3-day infection in mice. Ex vivo culturing of these infected LNSC populations revealed viable, replicating bacteria that grew on agar plates. These results highlight the unexplored potential of FRCs and BECs to serve as suitable growth niches for L. monocytogenes during foodborne infection and to contribute to the proinflammatory environment within the MLN that promotes clearance of listeriosis.
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Affiliation(s)
- Jamila S Tucker
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, 780 Rose Street, MS417, Lexington, KY 40536-0298, United States
| | - Hiba Khan
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, 780 Rose Street, MS417, Lexington, KY 40536-0298, United States
| | - Sarah E F D’Orazio
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, 780 Rose Street, MS417, Lexington, KY 40536-0298, United States
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2
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Orchanian SB, Lodoen MB. Monocytes as primary defenders against Toxoplasma gondii infection. Trends Parasitol 2023; 39:837-849. [PMID: 37633758 DOI: 10.1016/j.pt.2023.07.007] [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: 04/11/2023] [Revised: 07/14/2023] [Accepted: 07/21/2023] [Indexed: 08/28/2023]
Abstract
Monocytes are recruited from the bone marrow to sites of infection where they release cytokines and chemokines, function in antimicrobial immunity, and differentiate into macrophages and dendritic cells to control infection. Although many studies have focused on monocyte-derived macrophages and dendritic cells, recent work has examined the unique roles of monocytes during infection to promote immune defense. We focus on the effector functions of monocytes during infection with the parasite Toxoplasma gondii, and discuss the signals that mobilize monocytes to sites of infection, their production of inflammatory cytokines and antimicrobial mediators, their ability to shape the adaptive immune response, and their immunoregulatory functions. Insights from other infections, including Plasmodium and Listeria are also included for comparison and context.
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Affiliation(s)
- Stephanie B Orchanian
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, USA; Institute for Immunology, University of California Irvine, Irvine, California, USA
| | - Melissa B Lodoen
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, California, USA; Institute for Immunology, University of California Irvine, Irvine, California, USA.
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3
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Glover RC, Schwardt NH, Leano SKE, Sanchez ME, Thomason MK, Olive AJ, Reniere ML. A genome-wide screen in macrophages identifies PTEN as required for myeloid restriction of Listeria monocytogenes infection. PLoS Pathog 2023; 19:e1011058. [PMID: 37216395 PMCID: PMC10237667 DOI: 10.1371/journal.ppat.1011058] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 06/02/2023] [Accepted: 05/08/2023] [Indexed: 05/24/2023] Open
Abstract
Listeria monocytogenes (Lm) is an intracellular foodborne pathogen which causes the severe disease listeriosis in immunocompromised individuals. Macrophages play a dual role during Lm infection by both promoting dissemination of Lm from the gastrointestinal tract and limiting bacterial growth upon immune activation. Despite the relevance of macrophages to Lm infection, the mechanisms underlying phagocytosis of Lm by macrophages are not well understood. To identify host factors important for Lm infection of macrophages, we performed an unbiased CRISPR/Cas9 screen which revealed pathways that are specific to phagocytosis of Lm and those that are required for internalization of bacteria generally. Specifically, we discovered the tumor suppressor PTEN promotes macrophage phagocytosis of Lm and L. ivanovii, but not other Gram-positive bacteria. Additionally, we found that PTEN enhances phagocytosis of Lm via its lipid phosphatase activity by promoting adherence to macrophages. Using conditional knockout mice lacking Pten in myeloid cells, we show that PTEN-dependent phagocytosis is important for host protection during oral Lm infection. Overall, this study provides a comprehensive identification of macrophage factors involved in regulating Lm uptake and characterizes the function of one factor, PTEN, during Lm infection in vitro and in vivo. Importantly, these results demonstrate a role for opsonin-independent phagocytosis in Lm pathogenesis and suggest that macrophages play a primarily protective role during foodborne listeriosis.
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Affiliation(s)
- Rochelle C. Glover
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Nicole H. Schwardt
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Shania-Kate E. Leano
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Madison E. Sanchez
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Maureen K. Thomason
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Andrew J. Olive
- Department of Microbiology & Molecular Genetics, College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan, United States of America
| | - Michelle L. Reniere
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
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4
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Tucker JS, Cho J, Albrecht TM, Ferrell JL, D’Orazio SEF. Egress of Listeria monocytogenes from Mesenteric Lymph Nodes Depends on Intracellular Replication and Cell-to-Cell Spread. Infect Immun 2023; 91:e0006423. [PMID: 36916918 PMCID: PMC10112146 DOI: 10.1128/iai.00064-23] [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: 02/15/2023] [Accepted: 02/20/2023] [Indexed: 03/15/2023] Open
Abstract
The mesenteric lymph nodes (MLN) function as a barrier to systemic spread for both commensal and pathogenic bacteria in the gut. Listeria monocytogenes, a facultative intracellular foodborne pathogen, readily overcomes this barrier and spreads into the bloodstream, causing life-threatening systemic infections. We show here that intracellular replication protected L. monocytogenes from clearance by monocytes and neutrophils and promoted colonization of the small intestine-draining MLN (sMLN) but was not required for dissemination to the colon-draining MLN (cMLN). Intestinal tissue had enough free lipoate to support LplA2-dependent extracellular growth of L. monocytogenes, but exogenous lipoate in the MLN was severely limited, and so the bacteria could replicate only inside cells, where they used LplA1 to scavenge lipoate from host peptides. When foodborne infection was manipulated to allow ΔlplA1 L. monocytogenes to colonize the MLN to the same extent as wild-type bacteria, the mutant was still never recovered in the spleen or liver of any animal. We found that intracellular replication in the MLN promoted actin-based motility and cell-to-cell spread of L. monocytogenes and that rapid efficient exit from the MLN was actA dependent. We conclude that intracellular replication of L. monocytogenes in intestinal tissues is not essential and serves primarily to amplify bacterial burdens above a critical threshold needed to efficiently colonize the cMLN. In contrast, intracellular replication in the MLN is absolutely required for further systemic spread and serves primarily to promote ActA-mediated cell-to-cell spread.
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Affiliation(s)
- Jamila S. Tucker
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Jooyoung Cho
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Taylor M. Albrecht
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Jessica L. Ferrell
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
| | - Sarah E. F. D’Orazio
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
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5
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Wemyss K, Konkel JE. Gingival monocytes: Lessons from other barriers. Int J Biochem Cell Biol 2022; 145:106194. [PMID: 35276370 DOI: 10.1016/j.biocel.2022.106194] [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: 10/29/2021] [Revised: 03/04/2022] [Accepted: 03/06/2022] [Indexed: 10/18/2022]
Abstract
Unlike other non-lymphoid tissues monocytes comprise a large proportion of mononuclear phagocytes present within the gingiva. Their functions and fate remain poorly understood. The oral mucosa faces challenges common to all barrier surfaces, including constant exposure to antigens and the resident commensal bacteria, but also experiences ongoing mechanical damage from mastication. Gingiva monocytes may therefore possess both myeloid functions observed at other barrier sites, such as hypo-responsiveness to bacterial stimulation, and distinctive functions tailored by their unique environment. In this review, we discuss the establishment and function of monocytes and macrophages at several mucosal tissues, and posit potential functions of monocytes within the gingiva tissue.
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Affiliation(s)
- Kelly Wemyss
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, UK; Division of infection, Immunity and Respiratory Medicine, University of Manchester, Manchester M13 9PT, UK
| | - Joanne E Konkel
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PT, UK; Division of infection, Immunity and Respiratory Medicine, University of Manchester, Manchester M13 9PT, UK.
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6
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The use of foodborne infection to evaluate bacterial pathogenesis and host response. Methods Cell Biol 2022; 168:299-314. [PMID: 35366988 PMCID: PMC10064862 DOI: 10.1016/bs.mcb.2021.12.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Foodborne bacterial infections are a major cause of gastrointestinal illness. Murine models have been widely used to interrogate bacterial pathogenesis and host response to better understand the pathogens that cause gastrointestinal disease. Humans are usually exposed to these pathogens through consumption of contaminated food products. However, most murine models of foodborne infection rely on oral gavage to deliver pathogens directly into the stomach. While expedient, the gavage procedure may lead to microabrasions in the esophagus that allow direct access of the pathogen to the blood, which can alter bacterial pathogenesis and the host response under study. In this chapter, the alternative approach of foodborne infection through the consumption of inoculated food is described using the human pathogen Listeria monocytogenes (Lm). A detailed protocol of this methodology is provided with details of assessing bacterial burden and the host immune response. Translation of these methods to other foodborne pathogens will allow a more accurate assessment of bacterial pathogenesis and host immunity in more physiologic murine models.
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7
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Halsey CR, Glover RC, Thomason MK, Reniere ML. The redox-responsive transcriptional regulator Rex represses fermentative metabolism and is required for Listeria monocytogenes pathogenesis. PLoS Pathog 2021; 17:e1009379. [PMID: 34398937 PMCID: PMC8389512 DOI: 10.1371/journal.ppat.1009379] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 08/26/2021] [Accepted: 07/27/2021] [Indexed: 11/30/2022] Open
Abstract
The Gram-positive bacterium Listeria monocytogenes is the causative agent of the foodborne disease listeriosis, one of the deadliest bacterial infections known. In order to cause disease, L. monocytogenes must properly coordinate its metabolic and virulence programs in response to rapidly changing environments within the host. However, the mechanisms by which L. monocytogenes senses and adapts to the many stressors encountered as it transits through the gastrointestinal (GI) tract and disseminates to peripheral organs are not well understood. In this study, we investigated the role of the redox-responsive transcriptional regulator Rex in L. monocytogenes growth and pathogenesis. Rex is a conserved canonical transcriptional repressor that monitors the intracellular redox state of the cell by sensing the ratio of reduced and oxidized nicotinamide adenine dinucleotides (NADH and NAD+, respectively). Here, we demonstrated that L. monocytogenes Rex represses fermentative metabolism and is therefore required for optimal growth in the presence of oxygen. We also show that in vitro, Rex represses the production of virulence factors required for survival and invasion of the GI tract, as a strain lacking rex was more resistant to acidified bile and invaded host cells better than wild type. Consistent with these results, Rex was dispensable for colonizing the GI tract and disseminating to peripheral organs in an oral listeriosis model of infection. However, Rex-dependent regulation was required for colonizing the spleen and liver, and L. monocytogenes lacking the Rex repressor were nearly sterilized from the gallbladder. Taken together, these results demonstrated that Rex functions as a repressor of fermentative metabolism and suggests a role for Rex-dependent regulation in L. monocytogenes pathogenesis. Importantly, the gallbladder is the bacterial reservoir during listeriosis, and our data suggest redox sensing and Rex-dependent regulation are necessary for bacterial survival and replication in this organ. Listeriosis is a foodborne illness caused by Listeria monocytogenes and is one of the deadliest bacterial infections known, with a mortality rate of up to 30%. Following ingestion of contaminated food, L. monocytogenes disseminates from the gastrointestinal (GI) tract to peripheral organs, including the spleen, liver, and gallbladder. In this work, we investigated the role of the redox-responsive regulator Rex in L. monocytogenes growth and pathogenesis. We demonstrated that alleviation of Rex repression coordinates expression of genes necessary in the GI tract during infection, including fermentative metabolism, bile resistance, and invasion of host cells. Accordingly, Rex was dispensable for colonizing the GI tract of mice during an oral listeriosis infection. Interestingly, Rex-dependent regulation was required for bacterial replication in the spleen, liver, and gallbladder. Taken together, our results demonstrate that Rex-mediated redox sensing and transcriptional regulation are important for L. monocytogenes metabolic adaptation and virulence.
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Affiliation(s)
- Cortney R. Halsey
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Rochelle C. Glover
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Maureen K. Thomason
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Michelle L. Reniere
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
- * E-mail:
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8
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Louie A, Bhandula V, Portnoy DA. Secretion of c-di-AMP by Listeria monocytogenes Leads to a STING-Dependent Antibacterial Response during Enterocolitis. Infect Immun 2020; 88:e00407-20. [PMID: 33020211 PMCID: PMC7671888 DOI: 10.1128/iai.00407-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/27/2020] [Indexed: 12/24/2022] Open
Abstract
Stimulator of interferon genes (STING) acts as a cytoplasmic signaling hub of innate immunity that is activated by host-derived or bacterially derived cyclic dinucleotides. Listeria monocytogenes is a foodborne, facultative intracellular pathogen that secretes c-di-AMP and activates STING, yet the in vivo role of the STING pathway during bacterial pathogenesis remains unclear. In this study, we found that STING-deficient mice had increased weight loss and roughly 10-fold-increased systemic bacterial burden during L. monocytogenes-induced enterocolitis. Infection with a L. monocytogenes mutant impaired in c-di-AMP secretion failed to elicit a protective response, whereas a mutant with increased c-di-AMP secretion triggered enhanced protection. Type I interferon (IFN) is a major output of STING signaling; however, disrupting IFN signaling during L. monocytogenes-induced enterocolitis did not recapitulate STING deficiency. In the absence of STING, the intestinal immune response was associated with a reduced influx of inflammatory monocytes. These studies suggest that in barrier sites such as the intestinal tract, where pathogen-associated molecular patterns are abundant, cytosolic surveillance systems such as STING are well positioned to detect pathogenic bacteria.
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Affiliation(s)
- Alexander Louie
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, USA
| | - Varaang Bhandula
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, USA
| | - Daniel A Portnoy
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, California, USA
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9
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Leseigneur C, Lê-Bury P, Pizarro-Cerdá J, Dussurget O. Emerging Evasion Mechanisms of Macrophage Defenses by Pathogenic Bacteria. Front Cell Infect Microbiol 2020; 10:577559. [PMID: 33102257 PMCID: PMC7545029 DOI: 10.3389/fcimb.2020.577559] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 08/26/2020] [Indexed: 12/22/2022] Open
Abstract
Macrophages participate to the first line of defense against infectious agents. Microbial pathogens evolved sophisticated mechanisms to escape macrophage killing. Here, we review recent discoveries and emerging concepts on bacterial molecular strategies to subvert macrophage immune responses. We focus on the expanding number of fascinating subversive tools developed by Listeria monocytogenes, Staphylococcus aureus, and pathogenic Yersinia spp., illustrating diversity and commonality in mechanisms used by microorganisms with different pathogenic lifestyles.
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Affiliation(s)
- Clarisse Leseigneur
- Unité de Recherche Yersinia, Institut Pasteur, Paris, France.,Université de Paris, Sorbonne Paris Cité, Paris, France
| | - Pierre Lê-Bury
- Unité de Recherche Yersinia, Institut Pasteur, Paris, France.,Université de Paris, Sorbonne Paris Cité, Paris, France
| | - Javier Pizarro-Cerdá
- Unité de Recherche Yersinia, Institut Pasteur, Paris, France.,National Reference Laboratory Plague & Other Yersiniosis, Institut Pasteur, Paris, France.,WHO Collaborative Research & Reference Centre for Yersinia, Institut Pasteur, Paris, France
| | - Olivier Dussurget
- Unité de Recherche Yersinia, Institut Pasteur, Paris, France.,Université de Paris, Sorbonne Paris Cité, Paris, France
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10
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Imperato JN, Xu D, Romagnoli PA, Qiu Z, Perez P, Khairallah C, Pham QM, Andrusaite A, Bravo-Blas A, Milling SWF, Lefrancois L, Khanna KM, Puddington L, Sheridan BS. Mucosal CD8 T Cell Responses Are Shaped by Batf3-DC After Foodborne Listeria monocytogenes Infection. Front Immunol 2020; 11:575967. [PMID: 33042159 PMCID: PMC7518468 DOI: 10.3389/fimmu.2020.575967] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 08/24/2020] [Indexed: 12/24/2022] Open
Abstract
While immune responses have been rigorously examined after intravenous Listeria monocytogenes (Lm) infection, less is understood about its dissemination from the intestines or the induction of adaptive immunity after more physiologic models of foodborne infection. Consequently, this study focused on early events in the intestinal mucosa and draining mesenteric lymph nodes (MLN) using foodborne infection of mice with Lm modified to invade murine intestinal epithelium (InlAMLm). InlAMLm trafficked intracellularly from the intestines to the MLN and were associated with Batf3-independent dendritic cells (DC) in the lymphatics. Consistent with this, InlAMLm initially disseminated from the gut to the MLN normally in Batf3–/– mice. Activated migratory DC accumulated in the MLN by 3 days post-infection and surrounded foci of InlAMLm. At this time Batf3–/– mice displayed reduced InlAMLm burdens, implicating cDC1 in maximal bacterial accumulation in the MLN. Batf3–/– mice also exhibited profound defects in the induction and gut-homing of InlAMLm-specific effector CD8 T cells. Restoration of pathogen burden did not rescue antigen-specific CD8 T cell responses in Batf3–/– mice, indicating a critical role for Batf3 in generating anti-InlAMLm immunity following foodborne infection. Collectively, these data suggest that DC play diverse, dynamic roles in the early events following foodborne InlAMLm infection and in driving the establishment of intestinal Lm-specific effector T cells.
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Affiliation(s)
- Jessica Nancy Imperato
- Department of Microbiology and Immunology, Center for Infectious Diseases, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, United States
| | - Daqi Xu
- Department of Immunology, UConn Health, Farmington, CT, United States
| | - Pablo A Romagnoli
- Centro de Investigacion en Medicina Traslacional Severo Amuchastegui, Instituto Universitario de Ciencias Biomédicas de Córdoba, Córdoba, Argentina
| | - Zhijuan Qiu
- Department of Microbiology and Immunology, Center for Infectious Diseases, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, United States
| | - Pedro Perez
- Department of Microbiology and Immunology, Center for Infectious Diseases, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, United States
| | - Camille Khairallah
- Department of Microbiology and Immunology, Center for Infectious Diseases, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, United States
| | - Quynh-Mai Pham
- Department of Immunology, UConn Health, Farmington, CT, United States
| | - Anna Andrusaite
- Centre for Immunobiology, Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | | | - Simon W F Milling
- Centre for Immunobiology, Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Leo Lefrancois
- Department of Immunology, UConn Health, Farmington, CT, United States
| | - Kamal M Khanna
- Department of Microbiology, New York University, New York City, NY, United States
| | - Lynn Puddington
- Department of Immunology, UConn Health, Farmington, CT, United States
| | - Brian S Sheridan
- Department of Microbiology and Immunology, Center for Infectious Diseases, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, United States
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11
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Becattini S, Littmann ER, Seok R, Amoretti L, Fontana E, Wright R, Gjonbalaj M, Leiner IM, Plitas G, Hohl TM, Pamer EG. Enhancing mucosal immunity by transient microbiota depletion. Nat Commun 2020; 11:4475. [PMID: 32901029 PMCID: PMC7479140 DOI: 10.1038/s41467-020-18248-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 08/04/2020] [Indexed: 02/08/2023] Open
Abstract
Tissue resident memory CD8+ T cells (Trm) are poised for immediate reactivation at sites of pathogen entry and provide optimal protection of mucosal surfaces. The intestinal tract represents a portal of entry for many infectious agents; however, to date specific strategies to enhance Trm responses at this site are lacking. Here, we present TMDI (Transient Microbiota Depletion-boosted Immunization), an approach that leverages antibiotic treatment to temporarily restrain microbiota-mediated colonization resistance, and favor intestinal expansion to high densities of an orally-delivered Listeria monocytogenes strain carrying an antigen of choice. By augmenting the local chemotactic gradient as well as the antigenic load, this procedure generates a highly expanded pool of functional, antigen-specific intestinal Trm, ultimately enhancing protection against infectious re-challenge in mice. We propose that TMDI is a useful model to dissect the requirements for optimal Trm responses in the intestine, and also a potential platform to devise novel mucosal vaccination approaches.
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Affiliation(s)
- Simone Becattini
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
| | - Eric R Littmann
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Duchossois Family Institute, University of Chicago, Chicago, IL, 60606, USA
| | - Ruth Seok
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Luigi Amoretti
- Lucille Castori Center for Microbes Inflammation and Cancer, Molecular Microbiology Core Facility, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Emily Fontana
- Lucille Castori Center for Microbes Inflammation and Cancer, Molecular Microbiology Core Facility, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Roberta Wright
- Lucille Castori Center for Microbes Inflammation and Cancer, Molecular Microbiology Core Facility, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Mergim Gjonbalaj
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Ingrid M Leiner
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Duchossois Family Institute, University of Chicago, Chicago, IL, 60606, USA
| | - George Plitas
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Howard Hughes Medical Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Ludwig Center at Memorial Sloan Kettering Cancer Center, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Breast Service, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Tobias M Hohl
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Infectious Diseases Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Eric G Pamer
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Lucille Castori Center for Microbes Inflammation and Cancer, Molecular Microbiology Core Facility, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Infectious Diseases Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Duchossois Family Institute, University of Chicago, Chicago, IL, 60606, USA
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12
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Harter E, Lassnig C, Wagner EM, Zaiser A, Wagner M, Rychli K. The Novel Internalins InlP1 and InlP4 and the Internalin-Like Protein InlP3 Enhance the Pathogenicity of Listeria monocytogenes. Front Microbiol 2019; 10:1644. [PMID: 31396177 PMCID: PMC6664051 DOI: 10.3389/fmicb.2019.01644] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 07/03/2019] [Indexed: 01/08/2023] Open
Abstract
The pathogenicity of the human foodborne pathogen Listeria monocytogenes relies on virulence factors such as internalins. In 2009/2010 two L. monocytogenes strains were responsible for a serious listeriosis outbreak in Austria, Germany, and the Czech Republic. One of these clones, QOC1, which caused 14 cases including five fatalities, encodes the novel internalins inlP1, inlPq and inlP4, and the novel internalin-like protein inlP3 in the genomic region of hypervariable genetic hotspot 9 in addition to the standard set of virulence genes. The in silico prevalence study revealed that these genes rarely occur in L. monocytogenes, mainly in minor clonal complexes. To obtain first insights of the role of these genes in the pathogenicity of L. monocytogenes, we studied the gene expression under conditions mimicking the ingestion in the host. Expression of inlP1, inlP3, inlPq and inlP4 was increased under gastric stress and in intracellular bacteria grown in intestinal epithelial cells. Furthermore, colonization of the liver and the spleen was slightly, but significantly reduced 72 h post infection in an oral mouse infection model when inlP1 or inlP4 was deleted. Moreover, the impact of InlP1 and InlP3 in virulence was shown in vitro in human intestinal epithelial cells. In this study we conclusively demonstrate a potential contribution of uncommon novel internalins and an internalin-like protein to the pathogenicity of L. monocytogenes.
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Affiliation(s)
- Eva Harter
- Department for Farm Animals and Public Health in Veterinary Medicine, Institute of Food Safety, Food Technology and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Caroline Lassnig
- Department of Biomedical Sciences, Institute of Animal Breeding and Genetics and Biomodels Austria, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Eva Maria Wagner
- Department for Farm Animals and Public Health in Veterinary Medicine, Institute of Food Safety, Food Technology and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
- Austrian Competence Centre for Feed and Food Quality, Safety and Innovation – FFoQSI GmbH, Tulln, Austria
| | - Andreas Zaiser
- Department for Farm Animals and Public Health in Veterinary Medicine, Institute of Food Safety, Food Technology and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Martin Wagner
- Department for Farm Animals and Public Health in Veterinary Medicine, Institute of Food Safety, Food Technology and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
- Austrian Competence Centre for Feed and Food Quality, Safety and Innovation – FFoQSI GmbH, Tulln, Austria
| | - Kathrin Rychli
- Department for Farm Animals and Public Health in Veterinary Medicine, Institute of Food Safety, Food Technology and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
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13
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Pitts MG, D'Orazio SEF. Prostaglandin E 2 Inhibits the Ability of Neutrophils to Kill Listeria monocytogenes. THE JOURNAL OF IMMUNOLOGY 2019; 202:3474-3482. [PMID: 31061007 DOI: 10.4049/jimmunol.1900201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 04/10/2019] [Indexed: 12/29/2022]
Abstract
PGE2 is a lipid-signaling molecule with complex roles in both homeostasis and inflammation. Depending on the cellular context, PGE2 may also suppress certain immune responses. In this study, we tested whether PGE2 could inhibit bacterial killing by polymorphonuclear neutrophils (PMN) using a mouse model of foodborne listeriosis. We found that PGE2 pretreatment decreased the ability of PMN harvested from the bone marrow of either BALB/cByJ or C57BL/6J mice to kill Listeria monocytogenes in vitro. PGE2 treatment slowed the migration of PMN toward the chemoattractant leukotriene B4, decreased uptake of L. monocytogenes by PMN, and inhibited the respiratory burst of PMN compared with vehicle-treated cells. When immune cells were isolated from the livers of infected mice and tested directly ex vivo for the presence of PGE2, BALB/cByJ cells produced significantly more than C57BL/6J cells. Together, these data suggest that robust PGE2 production can suppress PMN effector functions, leading to decreased bacterial killing, which may contribute to the innate susceptibility of BALB/cByJ mice to infection with the facultative intracellular bacterial pathogen L. monocytogenes.
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Affiliation(s)
- Michelle G Pitts
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536
| | - Sarah E F D'Orazio
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536
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14
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D'Orazio SEF. Innate and Adaptive Immune Responses during Listeria monocytogenes Infection. Microbiol Spectr 2019; 7:10.1128/microbiolspec.gpp3-0065-2019. [PMID: 31124430 PMCID: PMC11086964 DOI: 10.1128/microbiolspec.gpp3-0065-2019] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Indexed: 12/15/2022] Open
Abstract
It could be argued that we understand the immune response to infection with Listeria monocytogenes better than the immunity elicited by any other bacteria. L. monocytogenes are Gram-positive bacteria that are genetically tractable and easy to cultivate in vitro, and the mouse model of intravenous (i.v.) inoculation is highly reproducible. For these reasons, immunologists frequently use the mouse model of systemic listeriosis to dissect the mechanisms used by mammalian hosts to recognize and respond to infection. This article provides an overview of what we have learned over the past few decades and is divided into three sections: "Innate Immunity" describes how the host initially detects the presence of L. monocytogenes and characterizes the soluble and cellular responses that occur during the first few days postinfection; "Adaptive Immunity" discusses the exquisitely specific T cell response that mediates complete clearance of infection and immunological memory; "Use of Attenuated Listeria as a Vaccine Vector" highlights the ways that investigators have exploited our extensive knowledge of anti-Listeria immunity to develop cancer therapeutics.
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Affiliation(s)
- Sarah E F D'Orazio
- University of Kentucky, Microbiology, Immunology & Molecular Genetics, Lexington, KY 40536-0298
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15
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Drolia R, Bhunia AK. Crossing the Intestinal Barrier via Listeria Adhesion Protein and Internalin A. Trends Microbiol 2019; 27:408-425. [PMID: 30661918 DOI: 10.1016/j.tim.2018.12.007] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 11/11/2018] [Accepted: 12/14/2018] [Indexed: 12/24/2022]
Abstract
The intestinal epithelial cell lining provides the first line of defense, yet foodborne pathogens such as Listeria monocytogenes can overcome this barrier; however, the underlying mechanism is not well understood. Though the host M cells in Peyer's patch and the bacterial invasion protein internalin A (InlA) are involved, L. monocytogenes can cross the gut barrier in their absence. The interaction of Listeria adhesion protein (LAP) with the host cell receptor (heat shock protein 60) disrupts the epithelial barrier, promoting bacterial translocation. InlA aids L. monocytogenes transcytosis via interaction with the E-cadherin receptor, which is facilitated by epithelial cell extrusion and goblet cell exocytosis; however, LAP-induced cell junction opening may be an alternative bacterial strategy for InlA access to E-cadherin and its translocation. Here, we summarize the strategies that L. monocytogenes employs to circumvent the intestinal epithelial barrier and compare and contrast these strategies with other enteric bacterial pathogens. Additionally, we provide implications of recent findings for food safety regulations.
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Affiliation(s)
- Rishi Drolia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA
| | - Arun K Bhunia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA; Department of Comparative Pathobiology, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA.
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16
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Neutrophils from Both Susceptible and Resistant Mice Efficiently Kill Opsonized Listeria monocytogenes. Infect Immun 2018; 86:IAI.00085-18. [PMID: 29426040 DOI: 10.1128/iai.00085-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 02/02/2018] [Indexed: 01/12/2023] Open
Abstract
Inbred mouse strains differ in their susceptibility to infection with the facultative intracellular bacterium Listeria monocytogenes, largely due to delayed or deficient innate immune responses. Previous antibody depletion studies suggested that neutrophils (polymorphonuclear leukocytes [PMN]) were particularly important for clearance in the liver, but the ability of PMN from susceptible and resistant mice to directly kill L. monocytogenes has not been examined. In this study, we showed that PMN infiltrated the livers of BALB/c/By/J (BALB/c) and C57BL/6 (B6) mice in similar numbers and that both cell types readily migrated toward leukotriene B4 in an in vitro chemotaxis assay. However, CFU burdens in the liver were significantly higher in BALB/c mice than in other strains, suggesting that PMN in the BALB/c liver might not be able to clear L. monocytogenes as efficiently as B6 PMN. Unprimed PMN harvested from either BALB/c or B6 bone marrow killed L. monocytogenes directly ex vivo, and pretreatment with autologous serum significantly enhanced killing efficiency for both. L. monocytogenes were internalized within 10 min and rapidly triggered intracellular production of reactive oxygen species in a dose-dependent manner. However, PMN from gp91phox-deficient mice also readily killed L. monocytogenes, which suggested that nonoxidative killing mechanisms may be sufficient for bacterial clearance. Together, these results indicate that there is not an intrinsic defect in the ability of PMN from susceptible BALB/c mice to kill L. monocytogenes and further suggest that if PMN function is impaired in BALB/c mice, it is likely due to locally produced modulating factors present in the liver during infection.
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17
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Pitts MG, D'Orazio SEF. A Comparison of Oral and Intravenous Mouse Models of Listeriosis. Pathogens 2018; 7:pathogens7010013. [PMID: 29361677 PMCID: PMC5874739 DOI: 10.3390/pathogens7010013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 01/11/2018] [Accepted: 01/19/2018] [Indexed: 12/18/2022] Open
Abstract
Listeria monocytogenes is one of several enteric microbes that is acquired orally, invades the gastric mucosa, and then disseminates to peripheral tissues to cause systemic disease in humans. Intravenous (i.v.) inoculation of mice with L. monocytogenes has been the most widely-used small animal model of listeriosis over the past few decades. The infection is highly reproducible and has been invaluable in deciphering mechanisms of adaptive immunity in vivo, particularly CD8+ T cell responses to intracellular pathogens. However, the i.v. model completely bypasses the gut phase of the infection. Recent advances in generating both humanized mice and murinized bacteria, as well as the development of a foodborne route of transmission has reignited interest in studying oral models of listeriosis. In this review, we analyze previously published reports to highlight both the similarities and differences in tissue colonization and host response to infection using either oral or i.v. inoculation.
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Affiliation(s)
- Michelle G Pitts
- Department of Microbiology, Immunology & Molecular Genetics, University of Kentucky, 800 Rose Street-MS417, Lexington, KY 40536-0298, USA.
| | - Sarah E F D'Orazio
- Department of Microbiology, Immunology & Molecular Genetics, University of Kentucky, 800 Rose Street-MS417, Lexington, KY 40536-0298, USA.
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18
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Radoshevich L, Cossart P. Listeria monocytogenes: towards a complete picture of its physiology and pathogenesis. Nat Rev Microbiol 2018; 16:32-46. [PMID: 29176582 DOI: 10.1038/nrmicro.2017.126] [Citation(s) in RCA: 465] [Impact Index Per Article: 77.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Listeria monocytogenes is a food-borne pathogen responsible for a disease called listeriosis, which is potentially lethal in immunocompromised individuals. This bacterium, first used as a model to study cell-mediated immunity, has emerged over the past 20 years as a paradigm in infection biology, cell biology and fundamental microbiology. In this Review, we highlight recent advances in the understanding of human listeriosis and L. monocytogenes biology. We describe unsuspected modes of hijacking host cell biology, ranging from changes in organelle morphology to direct effects on host transcription via a new class of bacterial effectors called nucleomodulins. We then discuss advances in understanding infection in vivo, including the discovery of tissue-specific virulence factors and the 'arms race' among bacteria competing for a niche in the microbiota. Finally, we describe the complexity of bacterial regulation and physiology, incorporating new insights into the mechanisms of action of a series of riboregulators that are critical for efficient metabolic regulation, antibiotic resistance and interspecies competition.
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Affiliation(s)
- Lilliana Radoshevich
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Département de Biologie Cellulaire et Infection, F-75015 Paris, France
- Inserm, U604, F-75015 Paris, France
- French National Institute for Agricultural Research (INRA), Unité sous-contrat 2020, F-75015 Paris, France
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, Iowa 52242, USA
| | - Pascale Cossart
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Département de Biologie Cellulaire et Infection, F-75015 Paris, France
- Inserm, U604, F-75015 Paris, France
- French National Institute for Agricultural Research (INRA), Unité sous-contrat 2020, F-75015 Paris, France
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19
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Jones GS, Smith VC, D'Orazio SEF. Listeria monocytogenes Replicate in Bone Marrow-Derived CD11c + Cells but Not in Dendritic Cells Isolated from the Murine Gastrointestinal Tract. THE JOURNAL OF IMMUNOLOGY 2017; 199:3789-3797. [PMID: 29055001 DOI: 10.4049/jimmunol.1700970] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 09/22/2017] [Indexed: 11/19/2022]
Abstract
Recent fate-mapping studies and gene-expression profiles suggest that commonly used protocols to generate bone marrow-derived cultured dendritic cells yield a heterogeneous mixture, including some CD11chi cells that may not have a bona fide counterpart in vivo. In this study, we provide further evidence of the discordance between ex vivo-isolated and in vitro-cultured CD11c+ cells by analyzing an additional phenotype, the ability to support cytosolic growth of the facultative intracellular bacterial pathogen Listeria monocytogenes Two days after foodborne infection of mice with GFP-expressing L. monocytogenes, a small percentage of CD103neg and CD103+ conventional dendritic cells (cDC) in the intestinal lamina propria and mesenteric lymph nodes were GFP+ However, in vitro infection of the same subsets of cells harvested from naive mice resulted in inefficient invasion by the bacteria (<0.1% of the inoculum). The few intracellular bacteria detected survived for only a few hours. In contrast, cultured CD103negCD11c+ cells induced by GM-CSF readily supported exponential growth of L. monocytogenes Flt3 ligand-induced cultures yielded CD103+CD11c+ cells that more closely resembled cDC, with only a modest level of L. monocytogenes replication. For both culture protocols, the longer the cells were maintained in vitro, the more readily they supported intracellular growth. The results of this study suggest that cDC are not a niche for intracellular growth of L. monocytogenes during intestinal infection of mice.
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Affiliation(s)
- Grant S Jones
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536
| | - Victoria C Smith
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536
| | - Sarah E F D'Orazio
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536
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20
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David DJV, Cossart P. Recent advances in understanding Listeria monocytogenes infection: the importance of subcellular and physiological context. F1000Res 2017; 6. [PMID: 28781746 PMCID: PMC5516218 DOI: 10.12688/f1000research.11363.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/10/2017] [Indexed: 01/04/2023] Open
Abstract
The bacterial pathogen
Listeria monocytogenes (
Lm) is the causative agent of listeriosis, a rare but fatal foodborne disease. During infection,
Lm can traverse several host barriers and enter the cytosol of a variety of cell types. Thus, consideration of the extracellular and intracellular niches of
Lm is critical for understanding the infection process. Here, we review advances in our understanding of
Lm infection and highlight how the interactions between the host and the pathogen are context dependent. We discuss discoveries of how
Lm senses entry into the host cell cytosol. We present findings concerning how the nature of the various cytoskeleton components subverted by
Lm changes depending on both the stage of infection and the subcellular context. We present discoveries of critical components required for
Lm traversal of physiological barriers. Interactions between the host gut microbiota and
Lm will be briefly discussed. Finally, the importance of
Lm biodiversity and post-genomics approaches as a promising way to discover novel virulence factors will be highlighted.
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Affiliation(s)
- Daryl J V David
- Unité des Interactions Bactéries-Cellules, Department of Cell Biology and Infection, Institut Pasteur, Paris, France
| | - Pascale Cossart
- Unité des Interactions Bactéries-Cellules, Department of Cell Biology and Infection, Institut Pasteur, Paris, France
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