1
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Pereira M, Ramalho T, Andrade WA, Durso DF, Souza MC, Fitzgerald KA, Golenbock DT, Silverman N, Gazzinelli RT. The IRAK1/IRF5 axis initiates IL-12 response by dendritic cells and control of Toxoplasma gondii infection. Cell Rep 2024; 43:113795. [PMID: 38367238 DOI: 10.1016/j.celrep.2024.113795] [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: 09/12/2023] [Revised: 12/19/2023] [Accepted: 01/30/2024] [Indexed: 02/19/2024] Open
Abstract
Activation of endosomal Toll-like receptor (TLR) 7, TLR9, and TLR11/12 is a key event in the resistance against the parasite Toxoplasma gondii. Endosomal TLR engagement leads to expression of interleukin (IL)-12 via the myddosome, a protein complex containing MyD88 and IL-1 receptor-associated kinase (IRAK) 4 in addition to IRAK1 or IRAK2. In murine macrophages, IRAK2 is essential for IL-12 production via endosomal TLRs but, surprisingly, Irak2-/- mice are only slightly susceptible to T. gondii infection, similar to Irak1-/- mice. Here, we report that upon T. gondii infection IL-12 production by different cell populations requires either IRAK1 or IRAK2, with conventional dendritic cells (DCs) requiring IRAK1 and monocyte-derived DCs (MO-DCs) requiring IRAK2. In both populations, we identify interferon regulatory factor 5 as the main transcription factor driving the myddosome-dependent IL-12 production during T. gondii infection. Consistent with a redundant role of DCs and MO-DCs, mutations that affect IL-12 production in both cell populations show high susceptibility to infection in vivo.
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Affiliation(s)
- Milton Pereira
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA.
| | - Theresa Ramalho
- Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Warrison A Andrade
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Danielle F Durso
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Maria C Souza
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Katherine A Fitzgerald
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Douglas T Golenbock
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Neal Silverman
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Ricardo T Gazzinelli
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA; Centro de Tecnologia de Vacinas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil; Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil.
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2
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Murillo-León M, Bastidas-Quintero AM, Endres NS, Schnepf D, Delgado-Betancourt E, Ohnemus A, Taylor GA, Schwemmle M, Staeheli P, Steinfeldt T. IFN-λ is protective against lethal oral Toxoplasma gondii infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.24.529861. [PMID: 36865100 PMCID: PMC9980175 DOI: 10.1101/2023.02.24.529861] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
Interferons are essential for innate and adaptive immune responses against a wide variety of pathogens. Interferon lambda (IFN-λ) protects mucosal barriers during pathogen exposure. The intestinal epithelium is the first contact site for Toxoplasma gondii (T. gondii) with its hosts and the first defense line that limits parasite infection. Knowledge of very early T. gondii infection events in the gut tissue is limited and a possible contribution of IFN-λ has not been investigated so far. Here, we demonstrate with systemic interferon lambda receptor (IFNLR1) and conditional (Villin-Cre) knockout mouse models and bone marrow chimeras of oral T. gondii infection and mouse intestinal organoids a significant impact of IFN-λ signaling in intestinal epithelial cells and neutrophils to T. gondii control in the gastrointestinal tract. Our results expand the repertoire of interferons that contribute to the control of T. gondii and may lead to novel therapeutic approaches against this world-wide zoonotic pathogen.
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Affiliation(s)
- Mateo Murillo-León
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Aura M. Bastidas-Quintero
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Niklas S. Endres
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
- Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
- Current address:Institute of Virology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Daniel Schnepf
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Current address: Immunoregulation Laboratory, The Francis Crick Institute, London, UK
| | | | - Annette Ohnemus
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Gregory A. Taylor
- Departments of Medicine; Molecular Genetics and Microbiology; and Immunology; and Center for the Study of Aging and Human Development, Duke University Medical Center, NC 27710 Durham, North Carolina, United States of America
- Geriatric Research, Education, and Clinical Center, Durham VA Health Care System, NC 27705 Durham, North Carolina, United States of America
| | - Martin Schwemmle
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Peter Staeheli
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
| | - Tobias Steinfeldt
- Institute of Virology, Medical Center University of Freiburg, 79104 Freiburg, Germany
- Faculty of Medicine, University of Freiburg, 79104 Freiburg, Germany
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3
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Cohn IS, Henrickson SE, Striepen B, Hunter CA. Immunity to Cryptosporidium: Lessons from Acquired and Primary Immunodeficiencies. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 209:2261-2268. [PMID: 36469846 PMCID: PMC9731348 DOI: 10.4049/jimmunol.2200512] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 08/30/2022] [Indexed: 01/04/2023]
Abstract
Cryptosporidium is a ubiquitous protozoan parasite that infects gut epithelial cells and causes self-limited diarrhea in immunocompetent individuals. However, in immunocompromised hosts with global defects in T cell function, this infection can result in chronic, life-threatening disease. In addition, there is a subset of individuals with primary immunodeficiencies associated with increased risk for life-threatening cryptosporidiosis. These patients highlight MHC class II expression, CD40-CD40L interactions, NF-κB signaling, and IL-21 as key host factors required for resistance to this enteric pathogen. Understanding which immune deficiencies do (or do not) lead to increased risk for severe Cryptosporidium may reveal mechanisms of parasite restriction and aid in the identification of novel strategies to manage this common pathogen in immunocompetent and deficient hosts.
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Affiliation(s)
- Ian S. Cohn
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Sarah E. Henrickson
- Institute for Immunology, University of Pennsylvania, Philadelphia, PA, USA
- Division of Allergy Immunology, Department of Pediatrics, The Children’s Hospital of Philadelphia, Philadelphia, PA, USA
| | - Boris Striepen
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Christopher A. Hunter
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
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4
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Lévy R, Langlais D, Béziat V, Rapaport F, Rao G, Lazarov T, Bourgey M, Zhou YJ, Briand C, Moriya K, Ailal F, Avery DT, Markle J, Lim AI, Ogishi M, Yang R, Pelham S, Emam M, Migaud M, Deswarte C, Habib T, Saraiva LR, Moussa EA, Guennoun A, Boisson B, Belkaya S, Martinez-Barricarte R, Rosain J, Belkadi A, Breton S, Payne K, Benhsaien I, Plebani A, Lougaris V, Di Santo JP, Neven B, Abel L, Ma CS, Bousfiha AA, Marr N, Bustamante J, Liu K, Gros P, Geissmann F, Tangye SG, Casanova JL, Puel A. Inherited human c-Rel deficiency disrupts myeloid and lymphoid immunity to multiple infectious agents. J Clin Invest 2021; 131:150143. [PMID: 34623332 DOI: 10.1172/jci150143] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/08/2021] [Indexed: 12/26/2022] Open
Abstract
We studied a child with severe viral, bacterial, fungal, and parasitic diseases, who was homozygous for a loss-of-function mutation of REL, encoding c-Rel, which is selectively expressed in lymphoid and myeloid cells. The patient had low frequencies of NK, effector memory cells reexpressing CD45RA (Temra) CD8+ T cells, memory CD4+ T cells, including Th1 and Th1*, Tregs, and memory B cells, whereas the counts and proportions of other leukocyte subsets were normal. Functional deficits of myeloid cells included the abolition of IL-12 and IL-23 production by conventional DC1s (cDC1s) and monocytes, but not cDC2s. c-Rel was also required for induction of CD86 expression on, and thus antigen-presenting cell function of, cDCs. Functional deficits of lymphoid cells included reduced IL-2 production by naive T cells, correlating with low proliferation and survival rates and poor production of Th1, Th2, and Th17 cytokines by memory CD4+ T cells. In naive CD4+ T cells, c-Rel is dispensable for early IL2 induction but contributes to later phases of IL2 expression. The patient's naive B cells displayed impaired MYC and BCL2L1 induction, compromising B cell survival and proliferation and preventing their differentiation into Ig-secreting plasmablasts. Inherited c-Rel deficiency disrupts the development and function of multiple myeloid and lymphoid cells, compromising innate and adaptive immunity to multiple infectious agents.
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Affiliation(s)
- Romain Lévy
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France.,Pediatric Immunology, Hematology and Rheumatology Unit, Necker Hospital for Sick Children, AP-HP, Paris, France
| | | | - Vivien Béziat
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France.,St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Franck Rapaport
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Geetha Rao
- Garvan Institute, Darlinghurst, New South Wales 2010, Australia
| | - Tomi Lazarov
- Memorial Sloan Kettering Institute, New York, New York, USA
| | | | - Yu J Zhou
- Columbia University, New York, New York, USA
| | - Coralie Briand
- Pediatric Immunology, Hematology and Rheumatology Unit, Necker Hospital for Sick Children, AP-HP, Paris, France
| | - Kunihiko Moriya
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France
| | | | | | - Janet Markle
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | | | - Masato Ogishi
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Rui Yang
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Simon Pelham
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Mehdi Emam
- McGill University, Montreal, Quebec, Canada
| | - Mélanie Migaud
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France
| | - Caroline Deswarte
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France
| | | | | | | | | | - Bertrand Boisson
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France.,St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Serkan Belkaya
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Ruben Martinez-Barricarte
- St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Jérémie Rosain
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France
| | - Aziz Belkadi
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France
| | - Sylvain Breton
- Pediatric Radiology, Necker Hospital for Sick Children, Paris, France
| | - Kathryn Payne
- Garvan Institute, Darlinghurst, New South Wales 2010, Australia
| | | | - Alessandro Plebani
- University of Brescia and ASST-Spedali Civili of Brescia, Brescia, Italy
| | - Vassilios Lougaris
- University of Brescia and ASST-Spedali Civili of Brescia, Brescia, Italy
| | | | - Bénédicte Neven
- University of Paris, Imagine Institute, Paris, France.,Pediatric Immunology, Hematology and Rheumatology Unit, Necker Hospital for Sick Children, AP-HP, Paris, France
| | - Laurent Abel
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France.,St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
| | - Cindy S Ma
- Garvan Institute, Darlinghurst, New South Wales 2010, Australia
| | | | - Nico Marr
- Sidra Medicine, Doha, Qatar.,College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar
| | - Jacinta Bustamante
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France.,St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA.,Center for the Study of Primary Immunodeficiencies, Necker Hospital for Sick Children, Paris, France
| | - Kang Liu
- Columbia University, New York, New York, USA
| | | | | | - Stuart G Tangye
- Garvan Institute, Darlinghurst, New South Wales 2010, Australia
| | - Jean-Laurent Casanova
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France.,St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA.,Howard Hughes Medical Institute (HHMI), New York, New York, USA
| | - Anne Puel
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Paris, France.,University of Paris, Imagine Institute, Paris, France.,St. Giles Laboratory of Human Genetics of Infectious Diseases, The Rockefeller University, New York, New York, USA
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5
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The many-sided contributions of NF-κB to T-cell biology in health and disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 361:245-300. [PMID: 34074496 DOI: 10.1016/bs.ircmb.2020.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
T cells (or T lymphocytes) exhibit a myriad of functions in immune responses, ranging from pathogen clearance to autoimmunity, cancer and even non-lymphoid tissue homeostasis. Therefore, deciphering the molecular mechanisms orchestrating their specification, function and gene expression pattern is critical not only for our comprehension of fundamental biology, but also for the discovery of novel therapeutic targets. Among the master regulators of T-cell identity, the functions of the NF-κB family of transcription factors have been under scrutiny for several decades. However, a more precise understanding of their pleiotropic functions is only just emerging. In this review we will provide a global overview of the roles of NF-κB in the different flavors of mature T cells. We aim at highlighting the complex and sometimes diverging roles of the five NF-κB subunits in health and disease.
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6
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Braun L, Brenier-Pinchart MP, Hammoudi PM, Cannella D, Kieffer-Jaquinod S, Vollaire J, Josserand V, Touquet B, Couté Y, Tardieux I, Bougdour A, Hakimi MA. The Toxoplasma effector TEEGR promotes parasite persistence by modulating NF-κB signalling via EZH2. Nat Microbiol 2019; 4:1208-1220. [PMID: 31036909 PMCID: PMC6591128 DOI: 10.1038/s41564-019-0431-8] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 03/18/2019] [Indexed: 12/20/2022]
Abstract
The protozoan parasite Toxoplasma gondii has co-evolved with its homeothermic hosts (humans included) strategies that drive its quasi-asymptomatic persistence in hosts, hence optimizing the chance of transmission to new hosts. Persistence, which starts with a small subset of parasites that escape host immune killing and colonize the so-called immune privileged tissues where they differentiate into a low replicating stage, is driven by the interleukin 12 (IL-12)-interferon-γ (IFN-γ) axis. Recent characterization of a family of Toxoplasma effectors that are delivered into the host cell, in which they rewire the host cell gene expression, has allowed the identification of regulators of the IL-12-IFN-γ axis, including repressors. We now report on the dense granule-resident effector, called TEEGR (Toxoplasma E2F4-associated EZH2-inducing gene regulator) that counteracts the nuclear factor-κB (NF-κB) signalling pathway. Once exported into the host cell, TEEGR ends up in the nucleus where it not only complexes with the E2F3 and E2F4 host transcription factors to induce gene expression, but also promotes shaping of a non-permissive chromatin through its capacity to switch on EZH2. Remarkably, EZH2 fosters the epigenetic silencing of a subset of NF-κB-regulated cytokines, thereby strongly contributing to the host immune equilibrium that influences the host immune response and promotes parasite persistence in mice.
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Affiliation(s)
- Laurence Braun
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Marie-Pierre Brenier-Pinchart
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Pierre-Mehdi Hammoudi
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Dominique Cannella
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | | | - Julien Vollaire
- OPTIMAL Small Animal Imaging Facility, Institute for Advanced Biosciences, Grenoble, France
| | - Véronique Josserand
- OPTIMAL Small Animal Imaging Facility, Institute for Advanced Biosciences, Grenoble, France
| | - Bastien Touquet
- Team Membrane and Cell Dynamics of Host Parasite Interactions, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Yohann Couté
- Université Grenoble Alpes, CEA, INSERM, Grenoble, France
| | - Isabelle Tardieux
- Team Membrane and Cell Dynamics of Host Parasite Interactions, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France
| | - Alexandre Bougdour
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France.
| | - Mohamed-Ali Hakimi
- Team Host-Pathogen Interactions and Immunity to Infection, Institute for Advanced Biosciences, INSERM U1209, CNRS UMR5309, Université Grenoble Alpes, Grenoble, France.
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7
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Mancini M, Caignard G, Charbonneau B, Dumaine A, Wu N, Leiva-Torres GA, Gerondakis S, Pearson A, Qureshi ST, Sladek R, Vidal SM. Rel-Dependent Immune and Central Nervous System Mechanisms Control Viral Replication and Inflammation during Mouse Herpes Simplex Encephalitis. THE JOURNAL OF IMMUNOLOGY 2019; 202:1479-1493. [DOI: 10.4049/jimmunol.1800063] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 12/21/2018] [Indexed: 01/01/2023]
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8
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Chen Y, Sharma S, Assis PA, Jiang Z, Elling R, Olive AJ, Hang S, Bernier J, Huh JR, Sassetti CM, Knipe DM, Gazzinelli RT, Fitzgerald KA. CNBP controls IL-12 gene transcription and Th1 immunity. J Exp Med 2018; 215:3136-3150. [PMID: 30442645 PMCID: PMC6279399 DOI: 10.1084/jem.20181031] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 09/05/2018] [Accepted: 10/23/2018] [Indexed: 12/22/2022] Open
Abstract
These studies reveal a previously unrecognized role for Cnbp as a novel transcriptional regulator engaged downstream of innate immune receptors controlling the c-Rel–IL-12–Th1 axis, which has important implications for both host defense and inflammatory disease. An inducible program of inflammatory gene expression is a hallmark of antimicrobial defenses. Recently, cellular nucleic acid–binding protein (CNBP) was identified as a regulator of nuclear factor-kappaB (NF-κB)–dependent proinflammatory cytokine gene expression. Here, we generated mice lacking CNBP and found that CNBP regulates a very restricted gene signature that includes IL-12β. CNBP resides in the cytosol of macrophages and translocates to the nucleus in response to diverse microbial pathogens and pathogen-derived products. Cnbp-deficient macrophages induced canonical NF-κB/Rel signaling normally but were impaired in their ability to control the activation of c-Rel, a key driver of IL-12β gene transcription. The nuclear translocation and DNA-binding activity of c-Rel required CNBP. Lastly, Cnbp-deficient mice were more susceptible to acute toxoplasmosis associated with reduced production of IL-12β, as well as a reduced T helper type 1 (Th1) cell IFN-γ response essential to controlling parasite replication. Collectively, these findings identify CNBP as important regulator of c-Rel–dependent IL-12β gene transcription and Th1 immunity.
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Affiliation(s)
- Yongzhi Chen
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Shruti Sharma
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA.,Department of Immunology, Tufts University School of Medicine, Boston, MA
| | - Patricia A Assis
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Zhaozhao Jiang
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Roland Elling
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Andrew J Olive
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA
| | - Saiyu Hang
- Division of Immunology, Department of Microbiology and Immunology, Harvard Medical School, Boston, MA
| | - Jennifer Bernier
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | - Jun R Huh
- Division of Immunology, Department of Microbiology and Immunology, Harvard Medical School, Boston, MA
| | - Christopher M Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA
| | - David M Knipe
- Department of Microbiology and Immunology, Harvard Medical School, Boston, MA
| | - Ricardo T Gazzinelli
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA.,Departamento de Bioquímica e Imunologia, Universidade Federal of Minas Gerais, Belo Horizonte, Brazil.,Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil
| | - Katherine A Fitzgerald
- Program in Innate Immunity, Department of Medicine, University of Massachusetts Medical School, Worcester, MA .,Centre for Molecular Inflammation Research, Department of Cancer Research and Molecular Medicine, Trondheim, Norway
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9
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STIM- and Orai-mediated calcium entry controls NF-κB activity and function in lymphocytes. Cell Calcium 2018; 74:131-143. [PMID: 30048879 DOI: 10.1016/j.ceca.2018.07.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 07/09/2018] [Accepted: 07/09/2018] [Indexed: 12/24/2022]
Abstract
The central role of Ca2+ signaling in the development of functional immunity and tolerance is well established. These signals are initiated by antigen binding to cognate receptors on lymphocytes that trigger store operated Ca2+ entry (SOCE). The underlying mechanism of SOCE in lymphocytes involves TCR and BCR mediated activation of Stromal Interaction Molecule 1 and 2 (STIM1/2) molecules embedded in the ER membrane leading to their activation of Orai channels in the plasma membrane. STIM/Orai dependent Ca2+ signals guide key antigen induced lymphocyte development and function principally through direct regulation of Ca2+ dependent transcription factors. The role of Ca2+ signaling in NFAT activation and signaling is well known and has been studied extensively, but a wide appreciation and mechanistic understanding of how Ca2+ signals also shape the activation and specificity of NF-κB dependent gene expression has lagged. Here we discuss and interpret what is known about Ca2+ dependent mechanisms of NF-kB activation, including what is known and the gaps in our understanding of how these signals control lymphocyte development and function.
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10
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Mitchell JP, Carmody RJ. NF-κB and the Transcriptional Control of Inflammation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2017; 335:41-84. [PMID: 29305014 DOI: 10.1016/bs.ircmb.2017.07.007] [Citation(s) in RCA: 293] [Impact Index Per Article: 41.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The NF-κB transcription factor was discovered 30 years ago and has since emerged as the master regulator of inflammation and immune homeostasis. It achieves this status by means of the large number of important pro- and antiinflammatory factors under its transcriptional control. NF-κB has a central role in inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease, and autoimmunity, as well as diseases comprising a significant inflammatory component such as cancer and atherosclerosis. Here, we provide an overview of the studies that form the basis of our understanding of the role of NF-κB subunits and their regulators in controlling inflammation. We also describe the emerging importance of posttranslational modifications of NF-κB in the regulation of inflammation, and highlight the future challenges faced by researchers who aim to target NF-κB transcriptional activity for therapeutic benefit in treating chronic inflammatory diseases.
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Affiliation(s)
- Jennifer P Mitchell
- Rheumatoid Arthritis Pathogenesis Centre of Excellence, Centre for Immunobiology, Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Ruaidhrí J Carmody
- Centre for Immunobiology, Institute of Infection, Immunity, and Inflammation, University of Glasgow, Glasgow, United Kingdom.
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Seumois G, Zapardiel-Gonzalo J, White B, Singh D, Schulten V, Dillon M, Hinz D, Broide DH, Sette A, Peters B, Vijayanand P. Transcriptional Profiling of Th2 Cells Identifies Pathogenic Features Associated with Asthma. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2016; 197:655-64. [PMID: 27271570 PMCID: PMC4936908 DOI: 10.4049/jimmunol.1600397] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/13/2016] [Indexed: 01/27/2023]
Abstract
Allergic asthma and rhinitis are two common chronic allergic diseases that affect the lungs and nose, respectively. Both diseases share clinical and pathological features characteristic of excessive allergen-induced type 2 inflammation, orchestrated by memory CD4(+) T cells that produce type 2 cytokines (Th2 cells). However, a large majority of subjects with allergic rhinitis do not develop asthma, suggesting divergence in disease mechanisms. Because Th2 cells play a pathogenic role in both these diseases and are also present in healthy nonallergic subjects, we performed global transcriptional profiling to determine whether there are qualitative differences in Th2 cells from subjects with allergic asthma, rhinitis, and healthy controls. Th2 cells from asthmatic subjects expressed higher levels of several genes that promote their survival as well as alter their metabolic pathways to favor persistence at sites of allergic inflammation. In addition, genes that enhanced Th2 polarization and Th2 cytokine production were also upregulated in asthma. Several genes that oppose T cell activation were downregulated in asthma, suggesting enhanced activation potential of Th2 cells from asthmatic subjects. Many novel genes with poorly defined functions were also differentially expressed in asthma. Thus, our transcriptomic analysis of circulating Th2 cells has identified several molecules that are likely to confer pathogenic features to Th2 cells that are either unique or common to both asthma and rhinitis.
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Affiliation(s)
- Grégory Seumois
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | | | - Brandie White
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Divya Singh
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | | | - Myles Dillon
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Denize Hinz
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - David H Broide
- Division of Rheumatology, Allergy, and Immunology, Department of Medicine, University of California, San Diego, La Jolla, CA 92093; and
| | - Alessandro Sette
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Bjoern Peters
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037;
| | - Pandurangan Vijayanand
- La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037; Clinical and Experimental Sciences, National Institute for Health Research Southampton Respiratory Biomedical Research Unit, University of Southampton, Faculty of Medicine, Southampton SO16 6YD, United Kingdom
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Intracellular Networks of the PI3K/AKT and MAPK Pathways for Regulating Toxoplasma gondii-Induced IL-23 and IL-12 Production in Human THP-1 Cells. PLoS One 2015; 10:e0141550. [PMID: 26528819 PMCID: PMC4631599 DOI: 10.1371/journal.pone.0141550] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 10/01/2015] [Indexed: 11/19/2022] Open
Abstract
Interleukin (IL)-23 and IL-12 are closely related in structure, and these cytokines regulate both innate and adaptive immunity. However, the precise signaling networks that regulate the production of each in Toxoplasma gondii-infected THP-1 monocytic cells, particularly the PI3K/AKT and MAPK signaling pathways, remain unknown. In the present study, T. gondii infection upregulated the expression of IL-23 and IL-12 in THP-1 cells, and both cytokines increased with parasite dose. IL-23 secretion was strongly inhibited by TLR2 monoclonal antibody (mAb) treatment in a dose-dependent manner and by TLR2 siRNA transfection, whereas IL-12 secretion was strongly inhibited by TLR4 mAb treatment dose-dependently and by TLR4 siRNA transfection. IL-23 production was dose-dependently inhibited by the PI3K inhibitors LY294002 and wortmannin, whereas IL-12 production increased dose-dependently. THP-1 cells exposed to live T. gondii tachyzoites underwent rapid p38 MAPK, ERK1/2 and JNK activation. IL-23 production was significantly upregulated by the p38 MAPK inhibitor SB203580 dose-dependently, whereas pretreatment with 10 μM SB203580 significantly downregulated IL-12 production. ERK1/2 inhibition by PD98059 was significantly downregulated IL-23 production but upregulated IL-12 production. JNK inhibition by SP600125 upregulated IL-23 production, but IL-12 production was significantly downregulated dose-dependently. T. gondii infection resulted in AKT activation, and AKT phosphorylation was inhibited dose-dependently after pretreatment with PI3K inhibitors. In T. gondii-infected THP-1 cells, ERK1/2 activation was regulated by PI3K; however, the phosphorylation of p38 MAPK and JNK was negatively modulated by the PI3K signaling pathway. Collectively, these results indicate that IL-23 production in T. gondii-infected THP-1 cells was regulated mainly by TLR2 and then by PI3K and ERK1/2; however, IL-12 production was mainly regulated by TLR4 and then by p38 MAPK and JNK. Our findings provide new insight concerning the intracellular networks of the PI3K/AKT and MAPK signaling cascades for regulating T. gondii-induced IL-23 and IL-12 secretion in human monocytic cells.
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Toxoplasma gondii upregulates interleukin-12 to prevent Plasmodium berghei-induced experimental cerebral malaria. Infect Immun 2014; 82:1343-53. [PMID: 24396042 DOI: 10.1128/iai.01259-13] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
A chronic infection with the parasite Toxoplasma gondii has previously been shown to protect mice against subsequent viral, bacterial, or protozoal infections. Here we have shown that a chronic T. gondii infection can prevent Plasmodium berghei ANKA-induced experimental cerebral malaria (ECM) in C57BL/6 mice. Treatment with soluble T. gondii antigens (STAg) reduced parasite sequestration and T cell infiltration in the brains of P. berghei-infected mice. Administration of STAg also preserved blood-brain barrier function, reduced ECM symptoms, and significantly decreased mortality. STAg treatment 24 h post-P. berghei infection led to a rapid increase in serum levels of interleukin 12 (IL-12) and gamma interferon (IFN-γ). By 5 days after P. berghei infection, STAg-treated mice had reduced IFN-γ levels compared to those of mock-treated mice, suggesting that reductions in IFN-γ at the time of ECM onset protected against lethality. Using IL-10- and IL-12βR-deficient mice, we found that STAg-induced protection from ECM is IL-10 independent but IL-12 dependent. Treatment of P. berghei-infected mice with recombinant IL-12 significantly decreased parasitemia and mortality. These data suggest that IL-12, either induced by STAg or injected as a recombinant protein, mediates protection from ECM-associated pathology potentially through early induction of IFN-γ and reduction in parasitemia. These results highlight the importance of early IL-12 induction in protection against ECM.
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Amarnath S. c-Rel in GVHD biology: a missing link. Eur J Immunol 2013; 43:2255-8. [PMID: 24037677 PMCID: PMC3860175 DOI: 10.1002/eji.201343924] [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: 07/22/2013] [Revised: 07/22/2013] [Accepted: 07/30/2013] [Indexed: 11/10/2022]
Abstract
Graft-versus-host disease (GVHD) is a major complication associated with allogeneic bone marrow transplantation (BMT). Recent advances in the treatment of lymphoid malignancies with BMT include exploring mechanisms that can inhibit GVHD while maintaining graft-versus-leukemic (GVL) effects. In this issue of the European Journal of Immunology, Yu et al. [Eur. J. Immunol. 2013.43: 2327-2337] demonstrate efficient separation of GVHD and GVL by abrogating c-Rel in T cells. Intrinsic c-Rel deficiency in T cells resulted in complete protection against GVHD in both major and minor histocompatibility mismatched murine models of BMT. Protection against GVHD was associated with a decreased presence of Th1 and Th17 cells with a concomitant increase in Treg-cell numbers. Interestingly, an intrinsic defect of c-Rel also resulted in decreased expression of the Th1-associated chemokine receptor CXCR3. Finally, the absence of c-Rel maintained GVL effects with significant tumor clearance in murine recipients. These data suggest that specific targeting of the T-cell-specific transcription factor c-Rel can inhibit GVHD while maintaining GVL effects.
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Affiliation(s)
- Shoba Amarnath
- Experimental Transplantation and Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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15
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NFκB attenuates IL-5 production and upregulates T-box transcription factors in Th2-like T cells. Cytotechnology 2013; 66:373-82. [PMID: 23934330 DOI: 10.1007/s10616-013-9585-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 05/08/2013] [Indexed: 01/21/2023] Open
Abstract
IL-5 plays important roles in eosinophil differentiation, expansion, and recruitment. The regulation of IL-5 seems critical for the treatment of eosinophil-mediated allergic reactions. However, the precise mechanisms for IL-5 regulation remain unknown. In this study, we investigated how IL-5 production is regulated. The transduction of GATA-3 into a murine T cell hybridoma resulted in acquiring the ability to produce IL-5 in response to an antigenic stimulus like Th2 cells. This production was dependent on the cAMP-PKA pathway, but not on p38 activation. Transduction of NIK largely impaired IL-5 production. RelA and RelB similarly impaired IL-5 production. RelA decreased not only IL-5 protein amount but mRNA. RelA also inhibited Il5-luciferase reporter activity. The transduction of GATA-3 decreased the expression of Tbx21 and Eomes, but the additional transduction of RelA abrogated the decreased expression of GATA-3-induced Tbx21 and Eomes. Furthermore, the transduction of T-bet or Eomes into the GATA-3-transduced T cell hybridoma impaired IL-5 production. These results suggested that strong enhancement of the NFκB pathway downregulates IL-5 production and upregulates T-box protein expression to shift an immune response from Th2 to inflammatory Th1.
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16
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TLR-independent neutrophil-derived IFN-γ is important for host resistance to intracellular pathogens. Proc Natl Acad Sci U S A 2013; 110:10711-6. [PMID: 23754402 DOI: 10.1073/pnas.1307868110] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
IFN-γ is a major cytokine that is critical for host resistance to a broad range of intracellular pathogens. Production of IFN-γ by natural killer and T cells is initiated by the recognition of pathogens by Toll-like receptors (TLRs). In an experimental model of toxoplasmosis, we have identified the presence of a nonlymphoid source of IFN-γ that was particularly evident in the absence of TLR-mediated recognition of Toxoplasma gondii. Genetically altered mice lacking all lymphoid cells due to deficiencies in Recombination Activating Gene 2 and IL-2Rγc genes also produced IFN-γ in response to the protozoan parasite. Flow-cytometry and morphological examinations of non-NK/non-T IFN-γ(+) cells identified neutrophils as the cell type capable of producing IFN-γ. Selective elimination of neutrophils in TLR11(-/-) mice infected with the parasite resulted in acute susceptibility similar to that observed in IFN-γ-deficient mice. Similarly, Salmonella typhimurium infection of TLR-deficient mice induces the appearance of IFN-γ(+) neutrophils. Thus, neutrophils are a crucial source for IFN-γ that is required for TLR-independent host protection against intracellular pathogens.
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Gilmore TD, Gerondakis S. The c-Rel Transcription Factor in Development and Disease. Genes Cancer 2012; 2:695-711. [PMID: 22207895 DOI: 10.1177/1947601911421925] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 08/08/2011] [Indexed: 12/21/2022] Open
Abstract
c-Rel is a member of the nuclear factor κB (NF-κB) transcription factor family. Unlike other NF-κB proteins that are expressed in a variety of cell types, high levels of c-Rel expression are found primarily in B and T cells, with many c-Rel target genes involved in lymphoid cell growth and survival. In addition to c-Rel playing a major role in mammalian B and T cell function, the human c-rel gene (REL) is a susceptibility locus for certain autoimmune diseases such as arthritis, psoriasis, and celiac disease. The REL locus is also frequently altered (amplified, mutated, rearranged), and expression of REL is increased in a variety of B and T cell malignancies and, to a lesser extent, in other cancer types. Thus, agents that modulate REL activity may have therapeutic benefits for certain human cancers and chronic inflammatory diseases.
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18
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Courtine E, Cagnard N, Mazzolini J, Antona M, Pène F, Fitting C, Jacques S, Rousseau C, Niedergang F, Gerondakis S, Chiche JD, Ouaaz F, Mira JP. Combined loss of cRel/p50 subunits of NF-κB leads to impaired innate host response in sepsis. Innate Immun 2012; 18:753-63. [PMID: 22408080 DOI: 10.1177/1753425912440296] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
NF-κB, which comprises homo- and hetero-dimers of the five members of the Rel family, plays a crucial role in immunity to infection. The cRel and p50 subunits have been implicated in the development and function of the immune cells, but their in vivo importance remains poorly explored in sepsis. We aimed to study the impact of the combined loss of these two subunits on the innate response to infection in a cecal ligation and puncture model of sepsis. We have explored the possible defects in host defense, including pathogen clearance, bacterial phagocytosis and cytokine plasma release. We also performed gene profiling of cRel(-/-)p50(-/-) and wild-type LPS-stimulated peritoneal macrophages. Deficiency of cRel and p50 led to enhanced mortality to sepsis that was associated with defective macrophages phagocytosis, decreased bacterial clearance and moderate cytokine response. Transcription profile analysis revealed a common inflammatory response but a significant down-regulated transcription of genes encoding for pathogen recognition receptors and antimicrobial molecules, supporting the in vivo findings in mice. In conclusion, the cRel and p50 subunits of NF-κB play an important combined role in the innate response and are crucial for survival and pathogen clearance in polymicrobial sepsis.
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Affiliation(s)
- Emilie Courtine
- CNRS, UMR 8104, INSERM, U1016, Institut Cochin, Paris, France
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19
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A key role for NF-κB transcription factor c-Rel in T-lymphocyte-differentiation and effector functions. Clin Dev Immunol 2012; 2012:239368. [PMID: 22481964 PMCID: PMC3310234 DOI: 10.1155/2012/239368] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 12/13/2011] [Accepted: 12/31/2011] [Indexed: 01/01/2023]
Abstract
The transcription factors of the Rel/NF-κB family function as key regulators of innate and adoptive immunity. Tightly and temporally controlled activation of NF-κB-signalling pathways ensures prevention of harmful immune cell dysregulation, whereas a loss of control leads to pathological conditions such as severe inflammation, autoimmune disease, and inflammation-associated oncogenesis. Five family members have been identified in mammals: RelA (p65), c-Rel, RelB, and the precursor proteins NF-κB1 (p105) and NF-κB2 (p100), that are processed into p50 and p52, respectively. While RelA-containing dimers are present in most cell types, c-Rel complexes are predominately found in cells of hematopoietic origin. In T-cell lymphocytes, certain genes essential for immune function such as Il2 and Foxp3 are directly regulated by c-Rel. Additionally, c-Rel-dependent IL-12 and IL-23 transcription by macrophages and dendritic cells is crucial for T-cell differentiation and effector functions. Accordingly, c-Rel expression in T cells and antigen-presenting cells (APCs) controls a delicate balance between tolerance and immunity. This review gives a selective overview on recent progress in understanding of diverse roles of c-Rel in regulating adaptive immunity.
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20
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Jin W, Chang M, Sun SC. Peli: a family of signal-responsive E3 ubiquitin ligases mediating TLR signaling and T-cell tolerance. Cell Mol Immunol 2012; 9:113-22. [PMID: 22307041 PMCID: PMC4002811 DOI: 10.1038/cmi.2011.60] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Revised: 12/26/2011] [Accepted: 12/28/2011] [Indexed: 12/24/2022] Open
Abstract
E3 ubiquitin ligases play a crucial role in regulating immune receptor signaling and modulating immune homeostasis and activation. One emerging family of such E3s is the Pelle-interacting (Peli) proteins, characterized by the presence of a cryptic forkhead-associated domain involved in substrate binding and an atypical RING domain mediating formation of both lysine (K) 63- and K48-linked polyubiquitin chains. A well-recognized function of Peli family members is participation in the signal transduction mediated by Toll-like receptors (TLRs) and IL-1 receptor. Recent gene targeting studies have provided important insights into the in vivo functions of Peli1 in the regulation of TLR signaling and inflammation. These studies have also extended the biological functions of Peli1 to the regulation of T-cell tolerance. Consistent with its immunoregulatory functions, Peli1 responds to different immune stimuli for its gene expression and catalytic activation. In this review, we discuss the recent progress, as well as the historical perspectives in the regulation and biological functions of Peli.
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Affiliation(s)
- Wei Jin
- Immunology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
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21
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Interferon-gamma- and perforin-mediated immune responses for resistance against Toxoplasma gondii in the brain. Expert Rev Mol Med 2011; 13:e31. [PMID: 22005272 DOI: 10.1017/s1462399411002018] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Toxoplasma gondii is an obligate intracellular protozoan parasite that causes various diseases, including lymphadenitis, congenital infection of fetuses and life-threatening toxoplasmic encephalitis in immunocompromised individuals. Interferon-gamma (IFN-γ)-mediated immune responses are essential for controlling tachyzoite proliferation during both acute acquired infection and reactivation of infection in the brain. Both CD4+ and CD8+ T cells produce this cytokine in response to infection, although the latter has more potent protective activity. IFN-γ can activate microglia, astrocytes and macrophages, and these activated cells control the proliferation of tachyzoites using different molecules, depending on cell type and host species. IFN-γ also has a crucial role in the recruitment of T cells into the brain after infection by inducing expression of the adhesion molecule VCAM-1 on cerebrovascular endothelial cells, and chemokines such as CXCL9, CXCL10 and CCL5. A recent study showed that CD8+ T cells are able to remove T. gondii cysts, which represent the stage of the parasite in chronic infection, from the brain through their perforin-mediated activity. Thus, the resistance to cerebral infection with T. gondii requires a coordinated network using both IFN-γ- and perforin-mediated immune responses. Elucidating how these two protective mechanisms function and collaborate in the brain against T. gondii will be crucial in developing a new method to prevent and eradicate this parasitic infection.
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22
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O'Brien KB, Schultz-Cherry S, Knoll LJ. Parasite-mediated upregulation of NK cell-derived gamma interferon protects against severe highly pathogenic H5N1 influenza virus infection. J Virol 2011; 85:8680-8. [PMID: 21734055 PMCID: PMC3165849 DOI: 10.1128/jvi.05142-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 06/23/2011] [Indexed: 02/01/2023] Open
Abstract
Outbreaks of influenza A viruses are associated with significant human morbidity worldwide. Given the increasing resistance to the available influenza drugs, new therapies for the treatment of influenza virus infection are needed. An alternative approach is to identify products that enhance a protective immune response. In these studies, we demonstrate that infecting mice with the Th1-inducing parasite Toxoplasma gondii prior to highly pathogenic avian H5N1 influenza virus infection led to decreased lung viral titers and enhanced survival. A noninfectious fraction of T. gondii soluble antigens (STAg) elicited an immune response similar to that elicited by live parasites, and administration of STAg 2 days after H5N1 influenza virus infection enhanced survival, lowered viral titers, and reduced clinical disease. STAg administration protected H5N1 virus-infected mice lacking lymphocytes, suggesting that while the adaptive immune response was not required for enhanced survival, it was necessary for STAg-mediated viral clearance. Mechanistically, we found that administration of STAg led to increased production of gamma interferon (IFN-γ) from natural killer (NK) cells, which were both necessary and sufficient for survival. Further, administration of exogenous IFN-γ alone enhanced survival from H5N1 influenza virus infection, although not to the same level as STAg treatment. These studies demonstrate that a noninfectious T. gondii extract enhances the protective immune response against severe H5N1 influenza virus infections even when a single dose is administered 2 days postinfection.
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Affiliation(s)
- Kevin B. O'Brien
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin 53706
| | - Stacey Schultz-Cherry
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee 38105
| | - Laura J. Knoll
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin 53706
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The ubiquitin ligase Peli1 negatively regulates T cell activation and prevents autoimmunity. Nat Immunol 2011; 12:1002-9. [PMID: 21874024 PMCID: PMC3178748 DOI: 10.1038/ni.2090] [Citation(s) in RCA: 153] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 07/19/2011] [Indexed: 02/03/2023]
Abstract
T cell activation is subject to tight regulation to avoid inappropriate responses to self antigens. Here we show that genetic deficiency in the ubiquitin ligase Peli1 caused hyperactivation of T cells and rendered T cells refractory to suppression by regulatory T cells and transforming growth factor-β (TGF-β). As a result, Peli1-deficient mice spontaneously developed autoimmunity characterized by multiorgan inflammation and autoantibody production. Peli1 deficiency resulted in the nuclear accumulation of c-Rel, a member of the NF-κB family of transcription factors with pivotal roles in T cell activation. Peli1 negatively regulated c-Rel by mediating its Lys48 (K48) ubiquitination. Our results identify Peli1 as a critical factor in the maintenance of peripheral T cell tolerance and demonstrate a previously unknown mechanism of c-Rel regulation.
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24
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Jordan KA, Dupont CD, Tait ED, Liou HC, Hunter CA. Role of the NF-κB transcription factor c-Rel in the generation of CD8+ T-cell responses to Toxoplasma gondii. Int Immunol 2011; 22:851-61. [PMID: 21118906 DOI: 10.1093/intimm/dxq439] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The nuclear factor κB transcription factor c-Rel is exclusively expressed in immune cells and plays a role in numerous cellular functions including proliferation, survival and production of chemokines and cytokines. c-Rel has also been implicated in the regulation of multiple genes involved in innate and adaptive immune responses to the intracellular protozoan parasite Toxoplasma gondii, in particular IL-12. To better understand how this transcription factor controls the CD8(+) T-cell response to this organism, wild-type (WT) and c-Rel(-/-) mice were challenged with a replication-deficient strain of T. gondii that expresses the model antigen ovalbumin (OVA). These studies revealed that c-Rel was required for optimal primary expansion of OVA-specific CD8(+) T cells and that immunized c-Rel-deficient mice were susceptible to challenge with a virulent strain of T. gondii. However, when c-Rel(-/-) cells specific for OVA were adoptively transferred into a WT recipient, or c-Rel(-/-) mice were treated with IL-12 at the time of immunization, there was no apparent proliferative defect. Surprisingly, upon secondary challenge, antigen-specific CD8(+) T cells in c-Rel(-/-) mice expanded to a much greater degree in terms of frequency as well as numbers when compared with WT mice. Despite this, the cytokine responses of c-Rel(-/-) mice remained defective, consistent with their susceptibility to secondary challenge. Together, these results indicate that in this infection model, the major influence of c-Rel in generation of CD8(+) T-cell responses is through its regulation of the inflammatory environment, rather than playing a substantial T-cell-intrinsic role.
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Affiliation(s)
- Kimberly A Jordan
- Department of Pathobiology, University of Pennsylvania, 380 South University Avenue, Philadelphia, PA 19104, USA
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25
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Balasubramani A, Mukasa R, Hatton RD, Weaver CT. Regulation of the Ifng locus in the context of T-lineage specification and plasticity. Immunol Rev 2011; 238:216-32. [PMID: 20969595 DOI: 10.1111/j.1600-065x.2010.00961.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Study of the development of distinct CD4(+) T-cell subsets from naive precursors continues to provide excellent opportunities for dissection of mechanisms that control lineage-specific gene expression or repression. Whereas it had been thought that the induction of transcription networks that control T-lineage commitment were highly stable, reinforced by epigenetic processes that confer heritability of functional phenotypes by the progeny of mature T cells, recent findings support a more dynamic view of T-lineage commitment. Here, we highlight advances in the mapping and functional characterization of cis elements in the Ifng locus that have provided new insights into the control of the chromatin structure and transcriptional activity of this signature T-helper 1 cell gene. We also examine epigenetic features of the Ifng locus that have evolved to enable its reprogramming for expression by other T-cell subsets, particularly T-helper 17 cells, and contrast features of the Ifng locus with those of the Il17a-Il17f locus, which appears less promiscuous.
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Affiliation(s)
- Anand Balasubramani
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
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26
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Mendes EA, Caetano BC, Penido MLO, Bruna-Romero O, Gazzinelli RT. MyD88-dependent protective immunity elicited by adenovirus 5 expressing the surface antigen 1 from Toxoplasma gondii is mediated by CD8(+) T lymphocytes. Vaccine 2011; 29:4476-84. [PMID: 21549794 DOI: 10.1016/j.vaccine.2011.04.044] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Revised: 04/07/2011] [Accepted: 04/15/2011] [Indexed: 10/18/2022]
Abstract
Toxoplasma gondii is an intracellular parasite widely spread around the world. The surface antigens (SAG) 1, 2 and 3 are the main proteins expressed on the surface of T. gondii tachyzoites. Replication-defective adenovirus serotype 5 (rAd5) is one of the most potent recombinant viral vectors for eliciting T cell-mediated immunity in mice and humans. Here we show that vaccination with rAd5 expressing SAG1 (AdSAG1), but neither SAG2 nor SAG3, induces protective immunity in the highly susceptible C57BL/6 mice challenged with T. gondii. Furthermore, we evaluated different immunological components involved on viral induced protective immunity. We observed that host protection elicited by AdSAG1 is highly dependent on IL-12, IFN-γ and CD8(+) T lymphocytes. Importantly, the induction of protective immunity (T cell-derived IFN-γ) was also dependent on Myeloid Differentiation Factor 88 (MyD88), and thus, likely to involve Toll-like Receptors. We conclude that protective parasite specific-CD8(+) T cells are elicited by a mechanism that involves MyD88-dependent induction of IL-12.
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Affiliation(s)
- Erica A Mendes
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
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Reinhard K, Huber M, Wostl C, Hellhund A, Toboldt A, Abass E, Casper B, Joeris T, Herr C, Bals R, Steinhoff U, Lohoff M, Visekruna A. c-Rel promotes type 1 and type 17 immune responses during Leishmania major infection. Eur J Immunol 2011; 41:1388-98. [DOI: 10.1002/eji.201041056] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 12/16/2010] [Accepted: 01/26/2011] [Indexed: 12/23/2022]
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Abstract
NF-κB is a critical regulator of gene expression during severe infections. NF-κB comprises homo- and heterodimers of proteins from the Rel family. Among them, p50 and p65 have been clearly implicated in the pathophysiology of sepsis. In contrast, the role of cRel in sepsis is still controversial and has been poorly studied in single-pathogen infections. We aimed to investigate the consequences of cRel deficiency in a cecal ligation and puncture (CLP) model of sepsis. We have approached the underlying mechanisms of host defense by analyzing bacterial clearance, systemic inflammation, and the distribution of spleen dendritic cell subsets. Moreover, by using a genome-wide technology, we have also analyzed the CLP-induced modifications in gene expression profiles both in wild-type (wt) and in rel(-/-) mice. The absence of cRel enhances mortality due to polymicrobial sepsis. Despite normal pathogen clearance, cRel deficiency leads to an altered systemic inflammatory response associated with a sustained loss of the spleen lymphoid dendritic cells. Furthermore, a whole-blood microarray study reveals that the differential outcome between wt and rel(-/-) mice during sepsis is preceded by remarkable changes in the expression of hundreds of genes involved in aspects of host-pathogen interaction, such as host survival and lipid metabolism. In conclusion, cRel is a key NF-κB member required for host antimicrobial defenses and a regulatory transcription subunit that controls the inflammatory and immune responses in severe infection.
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Partial depletion of CD4(+)CD25(+)Foxp3(+) T regulatory cells significantly increases morbidity during acute phase Toxoplasma gondii infection in resistant BALB/c mice. Microbes Infect 2011; 13:394-404. [PMID: 21262371 DOI: 10.1016/j.micinf.2011.01.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 11/14/2010] [Accepted: 01/11/2011] [Indexed: 11/23/2022]
Abstract
CD4(+)CD25(+)Foxp3(+) T regulatory (Treg) cells, are known to regulate responses to infectious agents. Here we compared disease progression in BALB/c and C57BL/6(B6) mice infected perorally with Toxoplasma gondii for 7 days and examined the affect of partial depletion of Treg cells in these mice. BALB/c mice were seen to be resistant to peroral infection whereas B6 mice were susceptible in terms of mortality. Although the depletion of Treg cells before infection had no effect on the survival of B6 or BALB/c mice, it resulted in increased parasite burdens in BALB/c mice, especially in the lamina propria, but not in B6 mice. Pro-inflammatory cytokines were also increased in Treg cells depleted BALB/c mice as compared to B6 mice. In addition Treg cell depleted BALB/c mice displayed increased ileal histopathology compared to their non-treated counterparts. These findings provide evidence for the contribution of Treg cells, in the resistance of BALB/c mice against peroral T. gondii infection.
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Abstract
Two distinct nuclear factor κB (NFκB) signaling pathways have been described; the canonical pathway that mediates inflammatory responses, and the non-canonical pathway that is involved in immune cell differentiation and maturation and secondary lymphoid organogenesis. The former is dependent on the IκB kinase adaptor molecule NEMO, the latter is independent of it. Here, we review the molecular mechanisms of regulation in each signaling axis and attempt to relate the apparent regulatory logic to the physiological function. Further, we review the recent evidence for extensive cross-regulation between these two signaling axes and summarize them in a wiring diagram. These observations suggest that NEMO-dependent and -independent signaling should be viewed within the context of a single NFκB signaling system, which mediates signaling from both inflammatory and organogenic stimuli in an integrated manner. As in other regulatory biological systems, a systems approach including mathematical models that include quantitative and kinetic information will be necessary to characterize the network properties that mediate physiological function, and that may break down to cause or contribute to pathology.
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Balasubramani A, Shibata Y, Crawford GE, Baldwin AS, Hatton RD, Weaver CT. Modular utilization of distal cis-regulatory elements controls Ifng gene expression in T cells activated by distinct stimuli. Immunity 2010; 33:35-47. [PMID: 20643337 DOI: 10.1016/j.immuni.2010.07.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Revised: 04/20/2010] [Accepted: 05/11/2010] [Indexed: 01/09/2023]
Abstract
Distal cis-regulatory elements play essential roles in the T lineage-specific expression of cytokine genes. We have mapped interactions of three trans-acting factors-NF-kappaB, STAT4, and T-bet-with cis elements in the Ifng locus. We find that RelA is critical for optimal Ifng expression and is differentially recruited to multiple elements contingent upon T cell receptor (TCR) or interleukin-12 (IL-12) plus IL-18 signaling. RelA recruitment to at least four elements is dependent on T-bet-dependent remodeling of the Ifng locus and corecruitment of STAT4. STAT4 and NF-kappaB therefore cooperate at multiple cis elements to enable NF-kappaB-dependent enhancement of Ifng expression. RelA recruitment to distal elements was similar in T helper 1 (Th1) and effector CD8(+) T (Tc1) cells, although T-bet was dispensable in CD8 effectors. These results support a model of Ifng regulation in which distal cis-regulatory elements differentially recruit key transcription factors in a modular fashion to initiate gene transcription induced by distinct activation signals.
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Affiliation(s)
- Anand Balasubramani
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Protective Toxoplasma gondii-specific T-cell responses require T-cell-specific expression of protein kinase C-theta. Infect Immun 2010; 78:3454-64. [PMID: 20498263 DOI: 10.1128/iai.01407-09] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Protein kinase C-theta (PKC-theta) is important for the activation of autoreactive T cells but is thought to be of minor importance for T-cell responses in infectious diseases, suggesting that PKC-theta may be a target for the treatment of T-cell-mediated autoimmune diseases. To explore the function of PKC-theta in a chronic persisting infection in which T cells are crucial for pathogen control, we infected BALB/c PKC-theta(-/-) and PKC-theta(+/+) wild-type mice with Toxoplasma gondii. The PKC-theta(-/-) mice succumbed to necrotizing Toxoplasma encephalitis due to an insufficient parasite control up to day 40, whereas the wild-type mice survived. The number of T. gondii-specific CD4 and CD8 T cells was significantly reduced in the PKC-theta(-/-) mice, resulting in the impaired production of protective cytokines (gamma interferon, tumor necrosis factor) and antiparasitic effector molecules (inducible nitric oxide, gamma interferon-induced GTPase) in the spleen and brain. In addition, Th2-cell numbers were reduced in infected the PKC-theta(-/-) mice, paralleled by the diminished GATA3 expression of PKC-theta(-/-) CD4 T cells and reduced T. gondii-specific IgG production in serum and cerebrospinal fluid. Western blot analysis of splenic CD4 and CD8 T cells revealed an impaired activation of the NF-kappaB, AP-1, and MAPK pathways in T. gondii-infected PKC-theta(-/-) mice. Adoptive transfer of wild-type CD4 plus CD8 T cells significantly protected PKC-theta(-/-) mice from death by increasing the numbers of gamma interferon-producing T. gondii-specific CD4 and CD8 T cells, illustrating a cell-autonomous, protective function of PKC-theta in T cells. These findings imply that PKC-theta inhibition drastically impairs T. gondii-specific T-cell responses with fatal consequences for intracerebral parasite control and survival.
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Regulation of CD8+ T cell responses to infection with parasitic protozoa. Exp Parasitol 2010; 126:318-25. [PMID: 20493842 DOI: 10.1016/j.exppara.2010.05.008] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 04/05/2010] [Accepted: 05/15/2010] [Indexed: 11/24/2022]
Abstract
There are over 10,000 species of parasitic protozoa, a subset of which can cause considerable disease in humans. Here we examine in detail the complex immune response generated during infection with a subset of these parasites: Trypanosoma cruzi, Leishmania sp., Toxoplasma gondii, and Plasmodium sp. While these particular species perhaps represent the most studied parasites in terms of understanding how T cells function during infection, it is clear that the lessons learned from this body of work are also relevant to the other protozoa known to induce a CD8(+) T cell response. This review will highlight some of the key studies that established that CD8(+) T cells play a major role in protective immunity to protozoa, the factors that promote the generation as well as maintenance of the CD8(+) T cell response during these infections, and draw attention to some of the gaps in our knowledge. Moreover, the development of new tools, including MHC-Class I tetramer reagents and the use of TCR transgenic mice or genetically modified parasites, has provided a better appreciation of how parasite specific CD8(+) T cell responses are initiated and new insights into their phenotypic plasticity.
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Deenick EK, Po L, Chapatte L, Murakami K, Lu YC, Elford AR, Saibil SD, Ruland J, Gerondakis S, Mak TW, Ohashi PS. c-Rel phenocopies PKCtheta but not Bcl-10 in regulating CD8+ T-cell activation versus tolerance. Eur J Immunol 2010; 40:867-77. [PMID: 19950170 DOI: 10.1002/eji.200939445] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Elucidating the signaling events that promote T-cell tolerance versus activation provides important insights for manipulating immunity in vivo. Previous studies have suggested that the absence of PKCtheta results in the induction of anergy and that the balance between the induction of the transcription factors NFAT, AP1 and NF-kappaB plays a key role in determining whether T-cell anergy or activation is induced. Here, we examine whether Bcl-10 and specific family members of NF-kappaB act downstream of PKCtheta to alter CD8(+) T-cell activation and/or anergy. We showed that T cells from mice deficient in c-Rel but not NF-kappaB1 (p50) have increased susceptibility to the induction of anergy, similar to T cells from PKCtheta-deficient mice. Surprisingly T cells from Bcl-10-deficient mice showed a strikingly different phenotype to the PKCtheta-deficient T cells, with a severe block in TCR-mediated activation. Furthermore, we have also shown that survival signals downstream of NF-kappaB, are uncoupled from signals that mediate T-cell anergy. These results suggest that c-Rel plays a critical role downstream of PKCtheta in controlling CD8(+) T-cell anergy induction.
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Affiliation(s)
- Elissa K Deenick
- Campbell Family Institute, Ontario Cancer Institute, University of Toronto, Toronto, ON, Canada.
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Harris TH, Wilson EH, Tait ED, Buckley M, Shapira S, Caamano J, Artis D, Hunter CA. NF-kappaB1 contributes to T cell-mediated control of Toxoplasma gondii in the CNS. J Neuroimmunol 2010; 222:19-28. [PMID: 20156658 DOI: 10.1016/j.jneuroim.2009.12.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Revised: 12/18/2009] [Accepted: 12/18/2009] [Indexed: 01/01/2023]
Abstract
In this study, the role of NF-kappaB1 was examined during toxoplasmosis. While wildtype BALB/c mice generated protective responses, NF-kappaB1(-/-) mice developed Toxoplasmic encephalitis, characterized by increased parasite burden and necrosis in the brain. Susceptibility was primarily associated with a local decrease in the number of CD8(+) T cells and IFN-gamma production, while accessory cell function appeared intact in NF-kappaB1(-/-) mice. Consistent with these findings, T cell transfer studies revealed that NF-kappaB1(-/-) T cells provided SCID mice less protection than wildtype T cells. These results demonstrate an intrinsic role for NF-kappaB1 in T cell-mediated immunity to Toxoplasmagondii.
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Affiliation(s)
- Tajie H Harris
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 380 S University Ave, Philadelphia, PA 19104, United States
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36
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Abstract
This article focuses on the functions of NF-kappaB that vitally impact lymphocytes and thus adaptive immunity. NF-kappaB has long been known to be essential for many of the responses of mature lymphocytes to invading pathogens. In addition, NF-kappaB has important functions in shaping the immune system so it is able to generate adaptive responses to pathogens. In both contexts, NF-kappaB executes critical cell-autonomous functions within lymphocytes as well as within supportive cells, such as antigen-presenting cells or epithelial cells. It is these aspects of NF-kappaB's physiologic impact that we address in this article.
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Shaw MH, Reimer T, Sánchez-Valdepeñas C, Warner N, Kim YG, Fresno M, Nuñez G. T cell-intrinsic role of Nod2 in promoting type 1 immunity to Toxoplasma gondii. Nat Immunol 2009; 10:1267-74. [PMID: 19881508 PMCID: PMC2803073 DOI: 10.1038/ni.1816] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Accepted: 09/24/2009] [Indexed: 02/08/2023]
Abstract
Nod2 belongs to the (NOD)-like receptor (NLR) family of proteins, which function as intracellular pathogen sensors in innate immune cells. Nod2-deficiency results in an impaired immune response against bacterial pathogens. However, our understanding of how this protein promotes host defense against intracellular parasites is unknown. Here we found that Nod2−/− mice showed reduced clearance of Toxoplasma gondii and decreased interferon-γ production. Reconstitution of T-cell deficient mice with Nod2−/− T cells followed by T. gondii infection revealed a T cell-intrinsic defect. Nod2−/− CD4+ T cells displayed poor helper T cell differentiation, which was associated with impaired IL-2 production and nuclear accumulation of c-Rel. These data revealed a T cell-intrinsic role of Nod2 signaling that is critical for host defense against T. gondii.
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Affiliation(s)
- Michael H Shaw
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan, USA
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38
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Gregersen PK, Amos CI, Lee AT, Lu E, Remmers EF, Kastner DL, Seldin MF, Criswell LA, Plenge RM, Holers VM, Mikuls T, Sokka T, Moreland LW, Bridges SL, Xie G, Begovich AB, Siminovitch KA. REL, encoding a member of the NF-kappaB family of transcription factors, is a newly defined risk locus for rheumatoid arthritis. Nat Genet 2009; 41:820-3. [PMID: 19503088 PMCID: PMC2705058 DOI: 10.1038/ng.395] [Citation(s) in RCA: 270] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Accepted: 05/01/2009] [Indexed: 12/27/2022]
Abstract
We conducted a genome-wide association study of rheumatoid arthritis in 2,418 cases and 4,504 controls from North America and identified an association at the REL locus, encoding c-Rel, on chromosome 2p13 (rs13031237, P = 6.01 x 10(-10)). Replication in independent case-control datasets comprising 2,604 cases and 2,882 controls confirmed this association, yielding an allelic OR = 1.25 (P = 3.08 x 10(-14)) for marker rs13031237 and an allelic OR = 1.21 (P = 2.60 x 10(-11)) for marker rs13017599 in the combined dataset. The combined dataset also provides definitive support for associations at both CTLA4 (rs231735; OR = 0.85; P = 6.25 x 10(-9)) and BLK (rs2736340; OR = 1.19; P = 5.69 x 10(-9)). c-Rel is an NF-kappaB family member with distinct functional properties in hematopoietic cells, and its association with rheumatoid arthritis suggests disease pathways that involve other recently identified rheumatoid arthritis susceptibility genes including CD40, TRAF1, TNFAIP3 and PRKCQ.
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Affiliation(s)
- Peter K. Gregersen
- The Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System, Manhasset, New York 11030, USA
| | | | - Annette T. Lee
- The Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System, Manhasset, New York 11030, USA
| | - Emily Lu
- University of Texas M.D. Anderson Cancer Center, Houston, USA
| | - Elaine F. Remmers
- Genetics and Genomics Branch, NIAMS, NIH, Bethesda, Maryland 20892, USA
| | - Daniel L. Kastner
- Genetics and Genomics Branch, NIAMS, NIH, Bethesda, Maryland 20892, USA
| | - Michael F. Seldin
- Rowe Program in Genetics, University of California at Davis, Davis, California 95616, USA
| | - Lindsey A Criswell
- Rosalind Russell Medical Research Center for Arthritis, Department of Medicine, University of California, San Francisco, USA
| | - Robert M. Plenge
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115 USA
| | | | | | | | | | | | - Gang Xie
- Mount Sinai Hospital and University Health Network, Toronto, Ontario M5G 1X5 Canada
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Lu YC, Kim I, Lye E, Shen F, Suzuki N, Suzuki S, Gerondakis S, Akira S, Gaffen SL, Yeh WC, Ohashi PS. Differential role for c-Rel and C/EBPbeta/delta in TLR-mediated induction of proinflammatory cytokines. THE JOURNAL OF IMMUNOLOGY 2009; 182:7212-21. [PMID: 19454718 DOI: 10.4049/jimmunol.0802971] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
TLR stimulation triggers a signaling pathway via MyD88 and IL-1R-associated kinase 4 that is essential for proinflammatory cytokine induction. Although NF-kappaB has been shown to be one of the key transcriptional regulators of these cytokines, evidence suggests that other factors may also be important. In this study, we showed that MyD88-deficient macrophages have defective c-Rel activation, which has been linked to IL-12p40 induction, but not IL-6 or TNF-alpha. We also investigated other transcription factors and showed that C/EBPbeta and C/EBPdelta expression was limited in MyD88- or IL-1R-associated kinase 4-deficient macrophages treated with LPS. Importantly, the absence of both C/EBPbeta and C/EBPdelta resulted in the impaired induction of proinflammatory cytokines stimulated by several TLR ligands. Our results identify c-Rel and C/EBPbeta/delta as important transcription factors in a MyD88-dependent pathway that regulate the induction of proinflammatory cytokines.
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Affiliation(s)
- Yong-Chen Lu
- The Campbell Family Institute for Breast Cancer Research, Ontario Cancer Institute, Ontario, Canada
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40
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Tian W, Liou HC. RNAi-mediated c-Rel silencing leads to apoptosis of B cell tumor cells and suppresses antigenic immune response in vivo. PLoS One 2009; 4:e5028. [PMID: 19347041 PMCID: PMC2661141 DOI: 10.1371/journal.pone.0005028] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Accepted: 03/05/2009] [Indexed: 12/13/2022] Open
Abstract
c-Rel is a member of the Rel/NF-κB transcription factor family and is predominantly expressed in lymphoid and myeloid cells, playing a critical role in lymphocyte proliferation and survival. Persistent activation of the c-Rel signal transduction pathway is associated with allergies, inflammation, autoimmune diseases, and a variety of human malignancies. To explore the potential of targeting c-Rel as a therapeutic agent for these disorders, we designed a small interfering RNA (siRNA) to silence c-Rel expression in vitro and in vivo. C-Rel-siRNA expression via a retroviral vector in a B cell tumor cell line leads to growth arrest and apoptosis of the tumor cells. Silencing c-Rel in primary B cells in vitro compromises their proliferative and survival response to CD40 activation signals, similar to the impaired response of c-Rel knockout B cells. Most important, in vivo silencing of c-Rel results in significant impairment in T cell-mediated immune responses to antigenic stimulation. Our study thus validates the efficacy of c-Rel-siRNA, and suggests the development of siRNA-based therapy, as well as small molecular inhibitors for the treatment of B cell tumors as well as autoimmune diseases.
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Affiliation(s)
- Wenzhi Tian
- Division of Immunology, Department of Medicine, Weill Medical College of Cornell University, New York, New York, United States of America
| | - Hsiou-Chi Liou
- Division of Immunology, Department of Medicine, Weill Medical College of Cornell University, New York, New York, United States of America
- * E-mail:
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41
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Miller CM, Boulter NR, Ikin RJ, Smith NC. The immunobiology of the innate response to Toxoplasma gondii. Int J Parasitol 2008; 39:23-39. [PMID: 18775432 DOI: 10.1016/j.ijpara.2008.08.002] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Revised: 08/07/2008] [Accepted: 08/11/2008] [Indexed: 01/17/2023]
Abstract
Toxoplasma gondii is a unique intracellular parasite. It can infect a variety of cells in virtually all warm-blooded animals. It has a worldwide distribution and, overall, around one-third of people are seropositive for the parasite, with essentially the entire human population being at risk of infection. For most people, T. gondii causes asymptomatic infection but the parasite can cause serious disease in the immunocompromised and, if contracted for the first time during pregnancy, can cause spontaneous abortion or congenital defects, which have a substantial emotional, social and economic impact. Toxoplasma gondii provokes one of the most potent innate, pro-inflammatory responses of all infectious disease agents. It is also a supreme manipulator of the immune response so that innate immunity to T. gondii is a delicate balance between the parasite and its host involving a coordinated series of cellular interactions involving enterocytes, neutrophils, dendritic cells, macrophages and natural killer cells. Underpinning these interactions is the regulation of complex molecular reactions involving Toll-like receptors, activation of signalling pathways, cytokine production and activation of anti-microbial effector mechanisms including generation of reactive nitrogen and oxygen intermediates.
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Affiliation(s)
- Catherine M Miller
- Institute for the Biotechnology of Infectious Diseases, University of Technology, Sydney, PO Box 123, Broadway, NSW 2007, Australia
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Saenz L, Lozano JJ, Valdor R, Baroja-Mazo A, Ramirez P, Parrilla P, Aparicio P, Sumoy L, Yélamos J. Transcriptional regulation by poly(ADP-ribose) polymerase-1 during T cell activation. BMC Genomics 2008; 9:171. [PMID: 18412984 PMCID: PMC2375913 DOI: 10.1186/1471-2164-9-171] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Accepted: 04/16/2008] [Indexed: 12/23/2022] Open
Abstract
Background Accumulating evidence suggests an important role for the enzyme poly(ADP-ribose) polymerase-1 (PARP-1) as an integral part of the gene expression regulatory machinery during development and in response to specific cellular signals. PARP-1 might modulate gene expression through its catalytic activity leading to poly(ADP-ribosyl)ation of nuclear proteins or by its physical association with relevant proteins. Recently, we have shown that PARP-1 is activated during T cell activation. However, the proposed role of PARP-1 in reprogramming T cell gene expression upon activation remains largely unexplored. Results In the present study we use oligonucleotide microarray analysis to gain more insight into the role played by PARP-1 during the gene expression reprogramming that takes place in T cells upon activation with anti-CD3 stimulation alone, or in combination with anti-CD28 co-stimulation. We have identified several groups of genes with expression modulated by PARP-1. The expression of 129 early-response genes to anti-CD3 seems to be regulated by PARP-1 either in a positive (45 genes) or in a negative manner (84 genes). Likewise, in the presence of co-stimulation (anti-CD3 + anti-CD28 stimulation), the expression of 203 genes is also regulated by PARP-1 either up (173 genes) or down (30 genes). Interestingly, PARP-1 deficiency significantly alters expression of genes associated with the immune response such as chemokines and genes involved in the Th1/Th2 balance. Conclusion This study provides new insights into changes in gene expression mediated by PARP-1 upon T cell activation. Pathway analysis of PARP-1 as a nuclear signalling molecule in T cells would be of relevance for the future development of new therapeutic approaches targeting PARP-1 in the acquired immune response.
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Affiliation(s)
- Luis Saenz
- Transplant Unit, Department of Surgery, University Hospital Virgen de Arrixaca, University of Murcia, Ciberehd, Murcia, Spain.
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Gerondakis S, Grumont R, Gugasyan R, Wong L, Isomura I, Ho W, Banerjee A. Unravelling the complexities of the NF-κB signalling pathway using mouse knockout and transgenic models. Oncogene 2006; 25:6781-99. [PMID: 17072328 DOI: 10.1038/sj.onc.1209944] [Citation(s) in RCA: 232] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The nuclear factor-kappaB (NF-kappaB) signalling pathway serves a crucial role in regulating the transcriptional responses of physiological processes that include cell division, cell survival, differentiation, immunity and inflammation. Here we outline studies using mouse models in which the core components of the NF-kappaB pathway, namely the IkappaB kinase subunits (IKKalpha, IKKbeta and NEMO), the IkappaB proteins (IkappaBalpha, IkappaBbeta, IkappaBvarepsilon and Bcl-3) and the five NF-kappaB transcription factors (NF-kappaB1, NF-kappaB2, c-Rel, RelA and RelB), have been genetically manipulated using transgenic and knockout technology.
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Affiliation(s)
- S Gerondakis
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
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44
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Tato CM, Mason N, Artis D, Shapira S, Caamano JC, Bream JH, Liou HC, Hunter CA. Opposing roles of NF-kappaB family members in the regulation of NK cell proliferation and production of IFN-gamma. Int Immunol 2006; 18:505-13. [PMID: 16481345 PMCID: PMC1800429 DOI: 10.1093/intimm/dxh391] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
It is well established that the nuclear factor-kappaB (NF-kappaB) family of transcription factors participates in the regulation of many aspects of innate and adaptive immunity. The majority of these reports have focused on the role of NF-kappaB in accessory cell and T or B cell function, but less is known about the role of NF-kappaB in NK cells. However, several studies have demonstrated that these transcription factors are required for NK cell production of IFN-gamma and proliferation. The studies presented here examine the role of two NF-kappaB members, c-Rel and p50, in NK cell function. In vitro data revealed that in the absence of c-Rel, NK cells have a defect in their ability to secrete IFN-gamma, but remain unaffected in their capacity to proliferate. In contrast, p50-/- NK cells have enhanced proliferative and IFN-gamma responses compared with wild-type NK cells. The latter findings suggest a role for p50 as a negative regulator of NK cell production of IFN-gamma and chromatin immunoprecipitation assays demonstrated the association of p50 with the IFN-gamma promoter of resting NK cells. Consistent with the in vitro studies, in vivo studies with NF-kappaB gene-deficient mice infected with Toxoplasma gondii revealed that the absence of p50 leads to enhanced NK cell proliferation and production of IFN-gamma. Together, these studies define distinct roles for c-Rel and p50 in the function of NK cells.
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Affiliation(s)
- Cristina M Tato
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia, PA 19104-6008, USA
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45
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Corn RA, Hunter C, Liou HC, Siebenlist U, Boothby MR. Opposing Roles for RelB and Bcl-3 in Regulation of T-Box Expressed in T Cells, GATA-3, and Th Effector Differentiation. THE JOURNAL OF IMMUNOLOGY 2005; 175:2102-10. [PMID: 16081776 DOI: 10.4049/jimmunol.175.4.2102] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
CD4+ T cells with a block in the NF-kappaB signaling pathway exhibit decreases in Th1 responses and diminished nuclear levels of multiple transactivating NF-kappaB/Rel/IkappaB proteins. To determine the lineage-intrinsic contributions of these transactivators to Th differentiation, T cells from mice deficient in specific subunits were cultured in exogenous cytokines promoting either Th1 or Th2 differentiation. RelB-deficient cells exhibited dramatic defects in Th1 differentiation and IFN-gamma production, whereas no consistent defect in either Th1 or Th2 responses was observed with c-Rel-deficient cells. In sharp contrast, Bcl-3-null T cells displayed no defect in IFN-gamma production, but their Th2 differentiation and IL-4, IL-5, and IL-13 production were significantly impaired. The absence of RelB led to a dramatic decrease in the expression of T-box expressed in T cells and Stat4. In contrast, Bcl-3-deficient cells exhibited decreased GATA-3, consistent with evidence that Bcl-3 can transactivate a gata3 promoter. These data indicate that Bcl-3 and RelB exert distinct and opposing effects on the expression of subset-determining transcription factors, suggesting that the characteristics of Th cell responses may be regulated by titrating the stoichiometry of transactivating NF-kappaB/Rel/IkappaB complexes in the nuclei of developing helper effector cells.
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Affiliation(s)
- Radiah A Corn
- Department of Microbiology, Meharry Medical College, Nashville, TN 37208, USA
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Grenningloh R, Kang BY, Ho IC. Ets-1, a functional cofactor of T-bet, is essential for Th1 inflammatory responses. ACTA ACUST UNITED AC 2005; 201:615-26. [PMID: 15728239 PMCID: PMC2213045 DOI: 10.1084/jem.20041330] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
To mount an effective type 1 immune response, type 1 T helper (Th1) cells must produce inflammatory cytokines and simultaneously suppress the expression of antiinflammatory cytokines. How these two processes are coordinately regulated at the molecular level is still unclear. In this paper, we show that the proto-oncogene E26 transformation-specific-1 (Ets-1) is necessary for T-bet to promote interferon-gamma production and that Ets-1 is essential for mounting effective Th1 inflammatory responses in vivo. In addition, Ets-1-deficient Th1 cells also produce a very high level of interleukin 10. Thus, Ets-1 plays a crucial and unique role in the reciprocal regulation of inflammatory and antiinflammatory Th responses.
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Affiliation(s)
- Roland Grenningloh
- Department of Medicine, Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, Boston, MA 02115, USA
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Mason NJ, Artis D, Hunter CA. New lessons from old pathogens: what parasitic infections have taught us about the role of nuclear factor-kappaB in the regulation of immunity. Immunol Rev 2005; 201:48-56. [PMID: 15361232 DOI: 10.1111/j.0105-2896.2004.00189.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The nuclear factor-kappaB (NF-kappaB) family of transcription factors is activated by many infectious and inflammatory stimuli. This family regulates the expression of multiple genes, whose products include cytokines, chemokines, adhesion molecules, and antiapoptotic factors that are important components of the innate and adaptive immune response. A prominent role of NF-kappaB transcription factors in resistance to a variety of infectious diseases was revealed by studies with mice that lack individual family members. However, little is known about the basis for these effects or about the role of individual family members during a coordinated immune response to infection. Diverse parasites such as Toxoplasma gondii, Leishmania major, and Trichuris muris provide a unique opportunity to understand the role of the NF-kappaB system in the development of innate and adaptive immunity to these infections. The basis for resistance and susceptibility to these parasites is well understood, and studies using these experimental systems have provided unique insights into the role of NF-kappaB in the regulation of T-helper 1 cell (Th1) and Th2 type responses. It has become clear that NF-kappaB family members have cell lineage-specific functions and that their relative importance varies with type of infection as well as route of pathogen entry. Thus, studies with models of parasitic infection have revealed that individual NF-kappaB family members perform distinct, nonoverlapping, and biologically significant functions in the regulation of immunity and inflammation.
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Affiliation(s)
- Nicola J Mason
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Denkers EY, Butcher BA, Del Rio L, Kim L. Manipulation of mitogen-activated protein kinase/nuclear factor-kappaB-signaling cascades during intracellular Toxoplasma gondii infection. Immunol Rev 2005; 201:191-205. [PMID: 15361242 DOI: 10.1111/j.0105-2896.2004.00180.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The intracellular protozoan Toxoplasma gondii exerts profound effects on nuclear factor-kappaB (NF-kappaB)- and mitogen-activated protein kinase (MAPK)-signaling cascades in macrophages. During early infection, nuclear translocation of NF-kappaB is blocked, and later, the cells display defects in lipopolysaccharide (LPS)-induced MAPK phosphorylation after undergoing initial activation in response to Toxoplasma itself. Infected macrophages that are subjected to triggering through Toll-like receptor 4 (TLR4) with LPS display defective production of tumor necrosis factor-alpha and IL-12 (IL-12) that likely reflects interference with NF-kappaB- and MAPK-signaling cascades. Nevertheless, T. gondii possesses molecules that themselves induce eventual proinflammatory cytokine synthesis. For interleukin-12, this occurs through both myeloid differentiation factor 88-dependent and chemokine receptor CCR5-dependent pathways. The balance between activation and interference with proinflammatory signaling is likely to reflect the need to achieve an appropriate level of immunity that allows the host and parasite to maintain a stable interaction.
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Affiliation(s)
- Eric Y Denkers
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
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