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Ling GS, Crawford G, Buang N, Bartok I, Tian K, Thielens NM, Bally I, Harker JA, Ashton-Rickardt PG, Rutschmann S, Strid J, Botto M. C1q restrains autoimmunity and viral infection by regulating CD8 + T cell metabolism. Science 2018; 360:558-563. [PMID: 29724957 DOI: 10.1126/science.aao4555] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Revised: 12/15/2017] [Accepted: 03/14/2018] [Indexed: 12/16/2022]
Abstract
Deficiency of C1q, the initiator of the complement classical pathway, is associated with the development of systemic lupus erythematosus (SLE). Explaining this association in terms of abnormalities in the classical pathway alone remains problematic because C3 deficiency does not predispose to SLE. Here, using a mouse model of SLE, we demonstrate that C1q, but not C3, restrains the response to self-antigens by modulating the mitochondrial metabolism of CD8+ T cells, which can themselves propagate autoimmunity. C1q deficiency also triggers an exuberant effector CD8+ T cell response to chronic viral infection leading to lethal immunopathology. These data establish a link between C1q and CD8+ T cell metabolism and may explain how C1q protects against lupus, with implications for the role of viral infections in the perpetuation of autoimmunity.
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Affiliation(s)
- Guang Sheng Ling
- Faculty of Medicine, Imperial College London, London W12 ONN, UK
| | - Greg Crawford
- Faculty of Medicine, Imperial College London, London W12 ONN, UK
| | - Norzawani Buang
- Faculty of Medicine, Imperial College London, London W12 ONN, UK
| | - Istvan Bartok
- Faculty of Medicine, Imperial College London, London W12 ONN, UK
| | - Kunyuan Tian
- Faculty of Medicine, Imperial College London, London W12 ONN, UK
| | | | - Isabelle Bally
- University Grenoble Alpes, CEA, CNRS, IBS, F-38000 Grenoble, France
| | - James A Harker
- Faculty of Medicine, Imperial College London, London W12 ONN, UK
| | | | | | - Jessica Strid
- Faculty of Medicine, Imperial College London, London W12 ONN, UK
| | - Marina Botto
- Faculty of Medicine, Imperial College London, London W12 ONN, UK.
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2
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Okoye I, Wang L, Pallmer K, Richter K, Ichimura T, Haas R, Crouse J, Choi O, Heathcote D, Lovo E, Mauro C, Abdi R, Oxenius A, Rutschmann S, Ashton-Rickardt PG. RETRACTED: T cell metabolism. The protein LEM promotes CD8⁺ T cell immunity through effects on mitochondrial respiration. Science 2015; 348:995-1001. [PMID: 25883318 DOI: 10.1126/science.aaa7516] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 04/06/2015] [Indexed: 12/11/2022]
Abstract
Protective CD8(+) T cell-mediated immunity requires a massive expansion in cell number and the development of long-lived memory cells. Using forward genetics in mice, we identified an orphan protein named lymphocyte expansion molecule (LEM) that promoted antigen-dependent CD8(+) T cell proliferation, effector function, and memory cell generation in response to infection with lymphocytic choriomeningitis virus. Generation of LEM-deficient mice confirmed these results. Through interaction with CR6 interacting factor (CRIF1), LEM controlled the levels of oxidative phosphorylation (OXPHOS) complexes and respiration, resulting in the production of pro-proliferative mitochondrial reactive oxygen species (mROS). LEM provides a link between immune activation and the expansion of protective CD8(+) T cells driven by OXPHOS and represents a pathway for the restoration of long-term protective immunity based on metabolically modified cytotoxic CD8(+) T cells.
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Affiliation(s)
- Isobel Okoye
- Section of Immunobiology, Division of Inflammation and Immunology, Department of Medicine, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Lihui Wang
- Section of Immunobiology, Division of Inflammation and Immunology, Department of Medicine, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Katharina Pallmer
- Institute of Microbiology, Eidgenössische Technische Hochschule Zurich (ETHZ), Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Kirsten Richter
- Institute of Microbiology, Eidgenössische Technische Hochschule Zurich (ETHZ), Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Takahuru Ichimura
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA 02215, USA
| | - Robert Haas
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
| | - Josh Crouse
- Institute of Microbiology, Eidgenössische Technische Hochschule Zurich (ETHZ), Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Onjee Choi
- Section of Immunobiology, Division of Inflammation and Immunology, Department of Medicine, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Dean Heathcote
- Section of Immunobiology, Division of Inflammation and Immunology, Department of Medicine, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Elena Lovo
- Section of Immunobiology, Division of Inflammation and Immunology, Department of Medicine, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Claudio Mauro
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
| | - Reza Abdi
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA 02215, USA
| | - Annette Oxenius
- Institute of Microbiology, Eidgenössische Technische Hochschule Zurich (ETHZ), Vladimir-Prelog-Weg 1-5/10, 8093 Zurich, Switzerland
| | - Sophie Rutschmann
- Section of Immunobiology, Division of Inflammation and Immunology, Department of Medicine, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Philip G Ashton-Rickardt
- Section of Immunobiology, Division of Inflammation and Immunology, Department of Medicine, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, UK. Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA 02215, USA.
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3
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Salisbury EM, Wang L, Choi O, Rutschmann S, Ashton-Rickardt PG. N-Ethyl-N-nitrosourea mutagenesis in the mouse provides strong genetic and in vivo evidence for the role of the Caspase Recruitment Domain (CARD) of CARD-MAGUK1 in T regulatory cell development. Immunology 2014; 141:446-56. [PMID: 24383645 DOI: 10.1111/imm.12207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 10/28/2013] [Accepted: 10/28/2013] [Indexed: 01/07/2023] Open
Abstract
Natural regulatory T (nTreg) cells generated in the thymus are essential throughout life for the maintenance of T-cell homeostasis and the prevention of autoimmunity. T-cell receptor (TCR)/CD28-mediated activation of nuclear factor-κB and (J)un (N)-terminal kinase pathways is known to play a key role in nTreg cell development but many of the predicted molecular interactions are based on extrapolations from non-Treg cell TCR stimulation with non-physiological ligands. For the first time, we provide strong genetic evidence of a scaffold function for the Caspase Recruitment Domain (CARD) of the TCR signalling protein CARD-MAGUK1 (CARMA1) in nTreg cell development in vivo. We report two, new, N-ethyl-N-nitrosourea-derived mutant mice, Vulpo and Zerda, with a profound block in the development of nTreg cells in the thymus as well as impaired inducible Treg cell differentiation in the periphery. Despite independent heritage, both mutants harbour different point mutations in the CARD of the CARMA1 protein. Mutations in vulpo and zerda do not affect expression levels of CARMA1 but still impair signalling through the TCR due to defective downstream Bcl-10 recruitment by the mutated CARD of CARMA1. Phenotypic differences observed between Vulpo and Zerda mutants suggest a role for the CARD of CARMA1 independent of Bcl-10 activation of downstream pathways. We conclude that our forward genetic approach demonstrates a critical role for the CARD function of CARMA1 in Treg cell development in vivo.
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Affiliation(s)
- Emma M Salisbury
- Section of Immunobiology, Division of Immunology and Inflammation, Department of Medicine, Faculty of Medicine, Imperial College London, London, UK
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4
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Abstract
The last decades have seen numerous approaches being used to decipher biological phenomena, notably the strategies we employ to defend ourselves against pathogenic attacks. From microarrays to genetics to computing technologies, all have supported a better but not yet comprehensive understanding of the pathways regulating our immune system. Limitations are notably exemplified by cases of immune deficiencies in humans that often result in high susceptibility to infections or even death, without the genetic cause being evident. To provide further insight into the mechanisms by which pathogen detection and eradication occur, several in vivo strategies can be used. The current review focuses on one of them, namely germline mutagenesis in the mouse. After describing the main technical aspects of this forward genetic approach, we will discuss particular germline mutants that have all been instrumental in deciphering innate or adaptive immune responses. Mutations in previously uncharacterized genes in the mouse, like Unc93B or Themis, have demonstrated the impartiality of forward genetics and led to the identification of new crucial immunity actors. Some mutants, like PanR1, have informed us on particular protein domains and their specific functions. Finally, certain mutations identified by this non-hypothesis-driven method have revealed previously unknown gene functions, as recently illustrated by memi, which links a particular nucleoside salvage enzyme to cell proliferation and apoptosis.
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Affiliation(s)
- Onjee Choi
- National Heart and Lung Institute, Imperial College London, London, UK
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5
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Arnold CN, Barnes MJ, Berger M, Blasius AL, Brandl K, Croker B, Crozat K, Du X, Eidenschenk C, Georgel P, Hoebe K, Huang H, Jiang Z, Krebs P, La Vine D, Li X, Lyon S, Moresco EMY, Murray AR, Popkin DL, Rutschmann S, Siggs OM, Smart NG, Sun L, Tabeta K, Webster V, Tomisato W, Won S, Xia Y, Xiao N, Beutler B. ENU-induced phenovariance in mice: inferences from 587 mutations. BMC Res Notes 2012; 5:577. [PMID: 23095377 PMCID: PMC3532239 DOI: 10.1186/1756-0500-5-577] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 09/03/2012] [Indexed: 11/22/2022] Open
Abstract
Background We present a compendium of N-ethyl-N-nitrosourea (ENU)-induced mouse mutations, identified in our laboratory over a period of 10 years either on the basis of phenotype or whole genome and/or whole exome sequencing, and archived in the Mutagenetix database. Our purpose is threefold: 1) to formally describe many point mutations, including those that were not previously disclosed in peer-reviewed publications; 2) to assess the characteristics of these mutations; and 3) to estimate the likelihood that a missense mutation induced by ENU will create a detectable phenotype. Findings In the context of an ENU mutagenesis program for C57BL/6J mice, a total of 185 phenotypes were tracked to mutations in 129 genes. In addition, 402 incidental mutations were identified and predicted to affect 390 genes. As previously reported, ENU shows strand asymmetry in its induction of mutations, particularly favoring T to A rather than A to T in the sense strand of coding regions and splice junctions. Some amino acid substitutions are far more likely to be damaging than others, and some are far more likely to be observed. Indeed, from among a total of 494 non-synonymous coding mutations, ENU was observed to create only 114 of the 182 possible amino acid substitutions that single base changes can achieve. Based on differences in overt null allele frequencies observed in phenotypic vs. non-phenotypic mutation sets, we infer that ENU-induced missense mutations create detectable phenotype only about 1 in 4.7 times. While the remaining mutations may not be functionally neutral, they are, on average, beneath the limits of detection of the phenotypic assays we applied. Conclusions Collectively, these mutations add to our understanding of the chemical specificity of ENU, the types of amino acid substitutions it creates, and its efficiency in causing phenovariance. Our data support the validity of computational algorithms for the prediction of damage caused by amino acid substitutions, and may lead to refined predictions as to whether specific amino acid changes are responsible for observed phenotypes. These data form the basis for closer in silico estimations of the number of genes mutated to a state of phenovariance by ENU within a population of G3 mice.
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Affiliation(s)
- Carrie N Arnold
- Department of Genetics, The Scripps Research Institute, La Jolla, CA 92037, USA
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6
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Choi O, Heathcote DA, Ho KK, Müller PJ, Ghani H, Lam EWF, Ashton-Rickardt PG, Rutschmann S. A deficiency in nucleoside salvage impairs murine lymphocyte development, homeostasis, and survival. J Immunol 2012; 188:3920-7. [PMID: 22407915 DOI: 10.4049/jimmunol.1102587] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The homeostasis of the immune system is tightly controlled by both cell-extrinsic and -intrinsic mechanisms. These regulators, not all known to date, drive cells in and out of quiescence when and where required to allow the immune system to function. In this article, we describe a deficiency in deoxycytidine kinase (DCK), one of the major enzymes of the nucleoside salvage pathway, which affects peripheral T cell homeostatic proliferation and survival. As a result of an N-ethyl-N-nitrosourea-induced mutation in the last α helix of DCK, a functionally null protein has been generated in the mouse and affects the composition of the hematopoietic system. Both B and T lymphocyte development is impaired, leading to a state of chronic lymphopenia and to a significant increase in the number of myeloid cells and erythrocytes. In the periphery, we found that mutant lymphocytes adopt a CD44(high)CD62L(low) memory phenotype, with high levels of proliferation and apoptosis. These phenotypes are notably the result of a cell-extrinsic-driven lymphopenia-induced proliferation as wild-type cells transferred into DCK-deficient recipients adopt the same profile. In addition, DCK also regulates lymphocyte quiescence in a cell-intrinsic manner. These data establish dCK as a new regulator of hematopoietic integrity and lymphocyte quiescence and survival.
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Affiliation(s)
- Onjee Choi
- Section of Immunobiology, Faculty of Medicine, Imperial College London, London W12 0NN, UK
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7
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Popkin DL, Teijaro JR, Sullivan BM, Urata S, Rutschmann S, de la Torre JC, Kunz S, Beutler B, Oldstone M. Hypomorphic mutation in the site-1 protease Mbtps1 endows resistance to persistent viral infection in a cell-specific manner. Cell Host Microbe 2011; 9:212-222. [PMID: 21402360 DOI: 10.1016/j.chom.2011.02.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 12/23/2010] [Accepted: 02/08/2011] [Indexed: 12/12/2022]
Abstract
The prototypic arenavirus lymphocytic choriomeningitis virus (LCMV), which naturally persists in rodents, represents a model for HIV, HBV, and HCV. Cleavage of the viral glycoprotein precursor by membrane-bound transcription factor peptidase, site 1 (Mbtps1 or site-1 protease), is crucial for the life cycle of arenaviruses and therefore represents a potential target for therapy. Recently, we reported a viable hypomorphic allele of Mbtps1 (woodrat) encoding a protease with diminished enzymatic activity. Using the woodrat allele, we examine the role of Mbtps1 during persistent LCMV infection. Surprisingly, Mbtps1 inhibition limits persistent but not acute viral infection and is associated with an organ/cell type-specific decrease in viral titers. Analysis of bone marrow-derived dendritic cells from woodrat mice supports their specific role in resolving persistent viral infection. These results support in vivo targeting of Mbtps1 in the treatment of arenavirus infections and demonstrate a critical role for dendritic cells in persistent viral infections.
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Affiliation(s)
- Daniel L Popkin
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA; Department of Genetics, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | - John R Teijaro
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Brian M Sullivan
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Shuzo Urata
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Sophie Rutschmann
- Department of Genetics, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Juan Carlos de la Torre
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Stefan Kunz
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Bruce Beutler
- Department of Genetics, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Michael Oldstone
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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Abstract
The innate arm of our immune system is the first line of defence against infections. In addition, it is believed to drive adaptive immune responses, which help fight pathogens and provide long-term memory. As such, the innate immune system is instrumental for protection against pathogens that would otherwise destroy their host. Although our understanding of the innate immune components involved in pathogen sensing and fighting is improving, it is still limited. This is particularly exemplified by increased documentation of innate immune deficiencies in humans that often result in high and recurrent susceptibility to infections or even death, without the genetic cause being evident. To provide further insight into the mechanisms by which pathogen sensing and eradication occur, several strategies can be used. The current review focuses on the forward genetic approaches that have been used to dissect innate immunity in the fruit fly and the mouse. For both animal models, forward genetics has been instrumental in the deciphering of innate immunity and has greatly improved our understanding of how we respond to invading pathogens.
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Crozat K, Hoebe K, Ugolini S, Hong NA, Janssen E, Rutschmann S, Mudd S, Sovath S, Vivier E, Beutler B. Jinx, an MCMV susceptibility phenotype caused by disruption of Unc13d: a mouse model of type 3 familial hemophagocytic lymphohistiocytosis. ACTA ACUST UNITED AC 2007; 204:853-63. [PMID: 17420270 PMCID: PMC2118559 DOI: 10.1084/jem.20062447] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Mouse cytomegalovirus (MCMV) susceptibility often results from defects of natural killer (NK) cell function. Here we describe Jinx, an N-ethyl-N-nitrosourea–induced MCMV susceptibility mutation that permits unchecked proliferation of the virus, causing death. In Jinx homozygotes, activated NK cells and cytotoxic T lymphocytes (CTLs) fail to degranulate, although they retain the ability to produce cytokines, and cytokine levels are markedly elevated in the blood of infected mutant mice. Jinx was mapped to mouse chromosome 11 on a total of 246 meioses and confined to a 4.60–million basepair critical region encompassing 122 annotated genes. The phenotype was ascribed to the creation of a novel donor splice site in Unc13d, the mouse orthologue of human MUNC13-4, in which mutations cause type 3 familial hemophagocytic lymphohistiocytosis (FHL3), a fatal disease marked by massive hepatosplenomegaly, anemia, and thrombocytopenia. Jinx mice do not spontaneously develop clinical features of hemophagocytic lymphohistiocytosis (HLH), but do so when infected with lymphocytic choriomeningitis virus, exhibiting hyperactivation of CTLs and antigen-presenting cells, and inadequate restriction of viral proliferation. In contrast, neither Listeria monocytogenes nor MCMV induces the syndrome. In mice, the HLH phenotype is conditional, which suggests the existence of a specific infectious trigger of FHL3 in humans.
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Affiliation(s)
- Karine Crozat
- The Scripps Research Institute (TSRI), La Jolla, CA 92037, USA
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10
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Munafó D, Johnson J, Ellis B, Rutschmann S, Beutler B, Catz S. Rab27a is a key component of the secretory machinery of azurophilic granules in granulocytes. Biochem J 2007; 402:229-39. [PMID: 17090228 PMCID: PMC1798439 DOI: 10.1042/bj20060950] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Neutrophils kill micro-organisms using microbicidal products that they release into the phagosome or into the extracellular space. The secretory machinery utilized by neutrophils is poorly characterized. We show that the small GTPase Rab27a is an essential component of the secretory machinery of azurophilic granules in granulocytes. Rab27a-deficient mice have impaired secretion of MPO (myeloperoxidase) into the plasma in response to lipopolysaccharide. Cell fractionation analysis revealed that Rab27a and the Rab27a effector protein JFC1/Slp1 (synaptotagmin-like protein 1) are distributed principally in the low-density fraction containing a minor population of MPO-containing granules. By immunofluorescence microscopy, we detected Rab27a and JFC1/Slp1 in a minor subpopulation of MPO-containing granules. Interference with the JFC1/Slp1-Rab27a secretory machinery impaired secretion of MPO in permeabilized neutrophils. The expression of Rab27a was dramatically increased when promyelocytic HL-60 cells were differentiated into granulocytes but not when they were differentiated into monocytes. Down-regulation of Rab27a in HL-60 cells by RNA interference did not affect JFC1/Slp1 expression but significantly decreased the secretion of MPO. Neither Rab27a nor JFC1/Slp1 was integrated into the phagolysosome membrane during phagocytosis. Neutrophils from Rab27a-deficient mice efficiently phagocytose zymosan opsonized particles and deliver MPO to the phagosome. We conclude that Rab27a and JFC1/Slp1 permit MPO release into the surrounding milieu and constitute key components of the secretory machinery of azurophilic granules in granulocytes. Our results suggest that the granules implicated in cargo release towards the surrounding milieu are molecularly and mechanistically different from those involved in their release towards the phagolysosome.
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Affiliation(s)
- Daniela B. Munafó
- *Department of Molecular and Experimental Medicine, Division of Biochemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla CA, 92037, U.S.A
| | - Jennifer L. Johnson
- *Department of Molecular and Experimental Medicine, Division of Biochemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla CA, 92037, U.S.A
| | - Beverly A. Ellis
- *Department of Molecular and Experimental Medicine, Division of Biochemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla CA, 92037, U.S.A
| | - Sophie Rutschmann
- †Department of Immunology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S.A
| | - Bruce Beutler
- †Department of Immunology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S.A
| | - Sergio D. Catz
- *Department of Molecular and Experimental Medicine, Division of Biochemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla CA, 92037, U.S.A
- To whom correspondence should be addressed (email )
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11
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Crozat K, Georgel P, Rutschmann S, Mann N, Du X, Hoebe K, Beutler B. Analysis of the MCMV resistome by ENU mutagenesis. Mamm Genome 2006; 17:398-406. [PMID: 16688530 DOI: 10.1007/s00335-005-0164-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Accepted: 01/23/2006] [Indexed: 01/14/2023]
Abstract
The mouse cytomegalovirus (MCMV) resistome is the set of host genes with nonredundant functions in resistance to MCMV infection. By screening 3,500 G(3) germline mutant mice ( approximately 1,750 gamete equivalents), we have identified eight transmissible mutations that create MCMV susceptibility in C57BL/6 mice. Among these, a mutation called Domino was noted to cause macrophage susceptibility to vesicular stomatitis virus (VSV) in vitro. This accessory phenotype was not corrected by type I interferon (IFN), which suggested a defect of the type I IFN pathway. Domino corresponds to a point mutation that alters the DNA binding domain of STAT1, leading to a defect of STAT1 activation. Identification of the Domino mutation demonstrates that an in vivo MCMV susceptibility screen is feasible and illustrates how it can provide insight into the resistome. Moreover, some mutations are far more deleterious than Domino in MCMV-infected mice, consistent with the interpretation that certain protein(s) unrelated to IFN production or signaling are more important than IFNs with regard to their net antiviral effects.
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Affiliation(s)
- Karine Crozat
- Department of Immunology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA.
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12
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Jiang Z, Georgel P, Li C, Choe J, Crozat K, Rutschmann S, Du X, Bigby T, Mudd S, Sovath S, Wilson IA, Olson A, Beutler B. Details of Toll-like receptor:adapter interaction revealed by germ-line mutagenesis. Proc Natl Acad Sci U S A 2006; 103:10961-6. [PMID: 16832055 PMCID: PMC1544157 DOI: 10.1073/pnas.0603804103] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The immunovariant N-ethyl-N-nitrosourea-induced mutations Pococurante (Poc) and Lackadaisical were found to alter MyD88, creating striking receptor-selective effects. Poc, in particular, prevented sensing of all MyD88-dependent Toll-like receptor (TLR) ligands except diacyl lipopeptides. Furthermore, Poc-site and classical BB loop mutations caused equivalent phenotypes when engrafted into any TLR/IL-1 receptor/resistance (TIR) domain. These observations, complemented by data from docking studies and site-directed mutagenesis, revealed that BB loops and Poc sites interact homotypically across the receptor:adapter signaling interface, whereas the C-terminal alpha(E)-helices support adapter:adapter and receptor:receptor oligomerization. We have thus defined the TIR domain surface that mediates association between TLRs and MyD88 and the surface required for MyD88 or TLR oligomerization. Moreover, MyD88 engages individual TLRs differently, suggesting the feasibility of selective pharmacologic TIR domain receptor blockade.
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Affiliation(s)
| | | | - Chenglong Li
- Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037; and
| | - Jungwoo Choe
- Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037; and
| | | | | | - Xin Du
- Departments of *Immunology and
| | - Tim Bigby
- Department of Medicine, Veterans Administration San Diego Health Care System, Mail Code 111J, 3350 La Jolla Village Drive, San Diego, CA 92161
| | | | | | - Ian A. Wilson
- Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037; and
| | - Arthur Olson
- Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037; and
| | - Bruce Beutler
- Departments of *Immunology and
- To whom correspondence should be addressed. E-mail:
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Beutler B, Jiang Z, Georgel P, Crozat K, Croker B, Rutschmann S, Du X, Hoebe K. Genetic analysis of host resistance: Toll-like receptor signaling and immunity at large. Annu Rev Immunol 2006; 24:353-89. [PMID: 16551253 DOI: 10.1146/annurev.immunol.24.021605.090552] [Citation(s) in RCA: 603] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Classical genetic methods, driven by phenotype rather than hypotheses, generally permit the identification of all proteins that serve nonredundant functions in a defined biological process. Long before this goal is achieved, and sometimes at the very outset, genetics may cut to the heart of a biological puzzle. So it was in the field of mammalian innate immunity. The positional cloning of a spontaneous mutation that caused lipopolysaccharide resistance and susceptibility to Gram-negative infection led directly to the understanding that Toll-like receptors (TLRs) are essential sensors of microbial infection. Other mutations, induced by the random germ line mutagen ENU (N-ethyl-N-nitrosourea), have disclosed key molecules in the TLR signaling pathways and helped us to construct a reasonably sophisticated portrait of the afferent innate immune response. A still broader genetic screen--one that detects all mutations that compromise survival during infection--is permitting fresh insight into the number and types of proteins that mammals use to defend themselves against microbes.
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Affiliation(s)
- Bruce Beutler
- Department of Immunology, Scripps Research Institute, La Jolla, California 92037, USA.
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14
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Rutschmann S, Hoebe K, Zalevsky J, Du X, Mann N, Dahiyat BI, Steed P, Beutler B. PanR1, a Dominant Negative Missense Allele of the Gene Encoding TNF-α (Tnf), Does Not Impair Lymphoid Development. J Immunol 2006; 176:7525-32. [PMID: 16751399 DOI: 10.4049/jimmunol.176.12.7525] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A dominant hypomorphic allele of Tnf, PanR1, was identified in a population of G(1) mice born to N-ethyl-N-nitrosourea-mutagenized sires. Macrophages from homozygotes produced no detectable TNF bioactivity, although normal quantities of immunoreactive TNF were secreted. The phenotype was confined to a critical region on mouse chromosome 17, and then ascribed to a C-->A transversion at position 3480 of the Tnf gene, corresponding to the amino acid substitution P138T. As a result of subunit exchange, the protein exerts a dominant-negative effect on normal TNF trimers, interfering with the trimer/receptor interaction. Homozygotes are highly susceptible to infection by Listeria monocytogenes, confirming the essential role of TNF in innate immune defense. However, PanR1 mutant mice show normal architecture of the spleen and Peyer's patches, suggesting that TNF is not essential for the formation of these lymphoid structures.
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Affiliation(s)
- Sophie Rutschmann
- Department of Immunology, Scripps Research Institute, La Jolla, CA 92037, USA
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15
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Janssen E, Tabeta K, Barnes MJ, Rutschmann S, McBride S, Bahjat KS, Schoenberger SP, Theofilopoulos AN, Beutler B, Hoebe K. Efficient T Cell Activation via a Toll-Interleukin 1 Receptor-Independent Pathway. Immunity 2006; 24:787-799. [PMID: 16782034 DOI: 10.1016/j.immuni.2006.03.024] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2005] [Revised: 03/15/2006] [Accepted: 03/30/2006] [Indexed: 01/09/2023]
Abstract
Here, we describe a previously unrecognized pathway for activation of antigen-specific adaptive immune responses that was independent of Toll-Interleukin 1 Receptor signaling and directed toward detection of antigens expressed by apoptotic cells. This pathway is represented within Flt-3 Ligand-derived dendritic cells (DCs) that represent immature lymphoid DCs, but not within GM-CSF-treated bone marrow-derived dendritic cells. Exposure of these DCs to apoptotic cells resulted in production of type I interferon and favored the development of cytotoxic T cell responses. The N-Ethyl-N-Nitrosourea-induced germline mutation 3d (Unc3b1(3d/3d)) abolished both MHC class I and II responses elicited by this pathway, whereas a null allele of Cd36 selectively abolished class II responses. We propose that this mode of adaptive immune activation evolved to permit the sensitive detection of intracellular microbial infections, particularly viral infections, which frequently induce apoptotic cell death, but may also be important in transplantation, autoimmunity, and vaccine development.
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Affiliation(s)
- Edith Janssen
- Department of Developmental Immunology, La Jolla Institute for Allergy and Immunology, San Diego, California 92121
| | - Koichi Tabeta
- Department of Immunology, The Scripps Research Institute, La Jolla, California 92037
| | - Michael J Barnes
- Department of Immunology, The Scripps Research Institute, La Jolla, California 92037
| | - Sophie Rutschmann
- Department of Immunology, The Scripps Research Institute, La Jolla, California 92037
| | - Sara McBride
- Department of Developmental Immunology, La Jolla Institute for Allergy and Immunology, San Diego, California 92121
| | | | - Stephen P Schoenberger
- Laboratory of Cellular Immunology, La Jolla Institute for Allergy and Immunology, San Diego, California 92121
| | | | - Bruce Beutler
- Department of Immunology, The Scripps Research Institute, La Jolla, California 92037
| | - Kasper Hoebe
- Department of Immunology, The Scripps Research Institute, La Jolla, California 92037.
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16
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Beutler B, Georgel P, Rutschmann S, Jiang Z, Croker B, Crozat K. Genetic analysis of innate resistance to mouse cytomegalovirus (MCMV). Brief Funct Genomic Proteomic 2006; 4:203-13. [PMID: 16420746 DOI: 10.1093/bfgp/4.3.203] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Innate immunity is inherited and is, therefore, particularly susceptible to analysis by classical genetic methods. The 'phenotype first' approach has already revealed the principal receptors of the innate immune system as well as several essential signalling intermediates. It has recently emerged that innate resistance to mouse cytomegalovirus (MCMV) infection depends upon a large number of host genes with non-redundant functions; hence, random germline mutagenesis frequently causes susceptibility to this pathogen. Approximately one in 30 pedigrees derived from N-ethyl-N-nitrosourea-mutagenised progenitors bears a recessive mutation that disrupts resistance to MCMV. Moreover, many of the genes required for resistance to MCMV will undoubtedly prove to have broad roles in immunity, creating resistance to many other microbes. The forward genetics approach offers an excellent opportunity to identify many of the key components of the innate immune system.
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Affiliation(s)
- Bruce Beutler
- The Scripps Research Institute, 10550 N. Torrey Pines Road, IMM-31, La Jolla, CA 92037, USA.
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17
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Georgel P, Crozat K, Lauth X, Makrantonaki E, Seltmann H, Sovath S, Hoebe K, Du X, Rutschmann S, Jiang Z, Bigby T, Nizet V, Zouboulis CC, Beutler B. A toll-like receptor 2-responsive lipid effector pathway protects mammals against skin infections with gram-positive bacteria. Infect Immun 2005; 73:4512-21. [PMID: 16040962 PMCID: PMC1201198 DOI: 10.1128/iai.73.8.4512-4521.2005] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
flake (flk), an N-ethyl-N-nitrosourea-induced recessive germ line mutation of C57BL/6 mice, impairs the clearance of skin infections by Streptococcus pyogenes and Staphylococcus aureus, gram-positive pathogens that elicit innate immune responses by activating Toll-like receptor 2 (TLR2). Positional cloning and sequencing revealed that flk is a novel allele of the stearoyl coenzyme A desaturase 1 gene (Scd1). flake homozygotes show reduced sebum production and are unable to synthesize the monounsaturated fatty acids (MUFA) palmitoleate (C(16:1)) and oleate (C(18:1)), both of which are bactericidal against gram-positive (but not gram-negative) organisms in vitro. However, intradermal MUFA administration to S. aureus-infected mice partially rescues the flake phenotype, which indicates that an additional component of the sebum may be required to improve bacterial clearance. In normal mice, transcription of Scd1-a gene with numerous NF-kappaB elements in its promoter--is strongly and specifically induced by TLR2 signaling. Similarly, the SCD1 gene is induced by TLR2 signaling in a human sebocyte cell line. These observations reveal the existence of a regulated, lipid-based antimicrobial effector pathway in mammals and suggest new approaches to the treatment or prevention of infections with gram-positive bacteria.
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Affiliation(s)
- Philippe Georgel
- Department of Immunology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
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18
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Hoebe K, Georgel P, Rutschmann S, Du X, Mudd S, Crozat K, Sovath S, Shamel L, Hartung T, Zähringer U, Beutler B. CD36 is a sensor of diacylglycerides. Nature 2005; 433:523-7. [PMID: 15690042 DOI: 10.1038/nature03253] [Citation(s) in RCA: 636] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Accepted: 12/03/2004] [Indexed: 11/09/2022]
Abstract
Toll-like receptor 2 (TLR2) is required for the recognition of numerous molecular components of bacteria, fungi and protozoa. The breadth of the ligand repertoire seems unusual, even if one considers that TLR2 may form heteromers with TLRs 1 and 6 (ref. 12), and it is likely that additional proteins serve as adapters for TLR2 activation. Here we show that an N-ethyl-N-nitrosourea-induced nonsense mutation of Cd36 (oblivious) causes a recessive immunodeficiency phenotype in which macrophages are insensitive to the R-enantiomer of MALP-2 (a diacylated bacterial lipopeptide) and to lipoteichoic acid. Homozygous mice are hypersusceptible to Staphylococcus aureus infection. Cd36(obl) macrophages readily detect S-MALP-2, PAM(2)CSK(4), PAM(3)CSK(4) and zymosan, revealing that some--but not all--TLR2 ligands are dependent on CD36. Already known as a receptor for endogenous molecules, CD36 is also a selective and nonredundant sensor of microbial diacylglycerides that signal via the TLR2/6 heterodimer.
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Affiliation(s)
- Kasper Hoebe
- Department of Immunology, The Scripps Research Institute, La Jolla, California 92037, USA
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19
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Gobert V, Gottar M, Matskevich AA, Rutschmann S, Royet J, Belvin M, Hoffmann JA, Ferrandon D. Dual Activation of the Drosophila Toll Pathway by Two Pattern Recognition Receptors. Science 2003; 302:2126-30. [PMID: 14684822 DOI: 10.1126/science.1085432] [Citation(s) in RCA: 273] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The Toll-dependent defense against Gram-positive bacterial infections in Drosophila is mediated through the peptidoglycan recognition protein SA (PGRP-SA). A mutation termed osiris disrupts the Gram-negative binding protein 1 (GNBP1) gene and leads to compromised survival of mutant flies after Gram-positive infections, but not after fungal or Gram-negative bacterial challenge. Our results demonstrate that GNBP1 and PGRP-SA can jointly activate the Toll pathway. The potential for a combination of distinct proteins to mediate detection of infectious nonself in the fly will refine the concept of pattern recognition in insects.
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Affiliation(s)
- Vanessa Gobert
- Unité Propre de Recherche 9022 du CNRS, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, F67084 Strasbourg Cedex, France
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20
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Rutschmann S, Kilinc A, Ferrandon D. Cutting edge: the toll pathway is required for resistance to gram-positive bacterial infections in Drosophila. J Immunol 2002; 168:1542-6. [PMID: 11823479 DOI: 10.4049/jimmunol.168.4.1542] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In Drosophila, the response against various microorganisms involves different recognition and signaling pathways, as well as distinct antimicrobial effectors. On the one hand, the immune deficiency pathway regulates the expression of antimicrobial peptides that are active against Gram-negative bacteria. On the other hand, the Toll pathway is involved in the defense against filamentous fungi and controls the expression of antifungal peptide genes. The gene coding for the only known peptide with high activity against Gram-positive bacteria, Defensin, is regulated by both pathways. So far, survival experiments to Gram-positive bacteria have been performed with Micrococcus luteus and have failed to reveal the involvement of one or the other pathway in host defense against such infections. In this study, we report that the Toll pathway, but not that of immune deficiency, is required for resistance to other Gram-positive bacteria and that this response does not involve Defensin.
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Affiliation(s)
- Sophie Rutschmann
- Institut de Biologie Moléculaire et Cellulaire, Unité Propre de Recherche 9022 du Centre National de la Recherche Scientifique, Strasbourg, France
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21
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Jung AC, Criqui MC, Rutschmann S, Hoffmann JA, Ferrandon D. Microfluorometer assay to measure the expression of beta-galactosidase and green fluorescent protein reporter genes in single Drosophila flies. Biotechniques 2001; 30:594-8, 600-1. [PMID: 11252795 DOI: 10.2144/01303rr04] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
beta-galactosidase and green fluorescent protein (GFP) are among the most commonly used reporter genes to monitor gene expression in various organisms including Drosophila melanogaster. Their expression is usually detected in a qualitative way by direct microscopic observations of cells, tissues, or whole animals. To measure in vivo the inducibility of two antimicrobial peptide genes expressed during the Drosophila innate immune response, we have adapted two reporter gene systems based on the beta-galactosidase enzymatic activity and GFP. We have designed a 96-well microplate fluorometric assay sensitive enough to quantify the expression of both reporter genes in single flies. The assay has enabled us to process efficiently and rapidly a large number of individual mutant flies generated during an ethylmethane sulfonate saturation mutagenesis of the Drosophila genome. This method may be used in any screen that requires the quantification of reporter gene activity in individual insects.
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Affiliation(s)
- A C Jung
- Centre National de la Recherche Scientifique, Strasbourg, France
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22
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Rutschmann S, Jung AC, Zhou R, Silverman N, Hoffmann JA, Ferrandon D. Role of Drosophila IKK gamma in a toll-independent antibacterial immune response. Nat Immunol 2000; 1:342-7. [PMID: 11017107 DOI: 10.1038/79801] [Citation(s) in RCA: 216] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have generated, by ethylmethane sulfonate mutagenesis, loss-of-function mutants in the Drosophila homolog of the mammalian I-kappa B kinase (IKK) complex component IKK gamma (also called NEMO). Our data show that Drosophila IKK gamma is required for the Relish-dependent immune induction of the genes encoding antibacterial peptides and for resistance to infections by Escherichia coli. However, it is not required for the Toll-DIF-dependent antifungal host defense. The results indicate distinct control mechanisms of the Rel-like transactivators DIF and Relish in the Drosophila innate immune response and show that Drosophila Toll does not signal through a IKK gamma-dependent signaling complex. Thus, in contrast to the vertebrate inflammatory response, IKK gamma is required for the activation of only one immune signaling pathway in Drosophila.
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Affiliation(s)
- S Rutschmann
- Institut de Biologie Moléculaire et Cellulaire, UPR 9022 du CNRS, 15, rue R. Descartes, F67084 Strasbourg, France
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23
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Rutschmann S, Jung AC, Hetru C, Reichhart JM, Hoffmann JA, Ferrandon D. The Rel protein DIF mediates the antifungal but not the antibacterial host defense in Drosophila. Immunity 2000; 12:569-80. [PMID: 10843389 DOI: 10.1016/s1074-7613(00)80208-3] [Citation(s) in RCA: 269] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We have isolated two Drosophila lines that carry point mutations in the gene coding for the NF-KB-like factor DIF. Like mutants of the Toll pathway, Dif mutant flies are susceptible to fungal but not to bacterial infections. Genetic epistasis experiments demonstrate that Dif mediates the Toll-dependent control of the inducibility of the antifungal peptide gene Drosomycin. Strikingly, DIF alone is required for the antifungal response in adults, but is redundant in larvae with Dorsal, another Rel family member. In Drosophila, Dif appears to be dedicated to the antifungal defense elicited by fungi and gram-positive bacteria. We discuss in this light the possibility that NF-KB1/p50 might be required more specifically in the innate immune response against gram-positive bacteria in mammals.
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Affiliation(s)
- S Rutschmann
- Institut de Biologie Moléculaire et Cellulaire, UPR 9022 du CNRS, Strasbourg, France
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24
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Alkan SS, Rutschmann S, Grogg D, Erb P. Effects of a new protein kinase C inhibitor CGP 41251 on T cell functions: inhibition of activation, growth, and target cell killing. Cell Immunol 1993; 150:137-48. [PMID: 8102085 DOI: 10.1006/cimm.1993.1185] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The effects of CGP 41251, a specific inhibitor of protein kinase C (PKC), its inactive derivative CGP 42700, and of staurosporine have been analyzed in vitro on T lymphocyte functions. The proliferation of fresh human peripheral blood lymphocytes stimulated with antigen (PPD) or anti-CD3 mAb was strongly inhibited by both staurosporine (IC50 < 0.01 microM) and CGP 41251 (IC50 = 0.092 microM) but not by the PKC inactive compound CGP 42700 (IC50 > 10 microM). Antigen-specific activation and proliferation of mouse lymph node T cells was inhibited by staurosporine and CGP 41251 with IC50 values of 0.008 and 0.05 microM, respectively. The inactive derivative caused 50% inhibition in this mouse T cell assay only at concentrations of 25 microM. In order to evaluate possible differential effects of PKC inhibitors on CD4+ T cell subsets, murine T helper cell type 1 (Th1) and type 2 (Th2) clones were used. The KLH-specific clone 9/6 secretes IL-2 and IFN-gamma (Th1), whereas clone 9A/B does not secrete these lymphokines but secretes IL-4 and IL-5 (Th2). It was found that CGP 41251 inhibited antigen-induced proliferation of both Th1 and Th2 equally well with an IC50 of 0.02 microM. Furthermore, CGP 41251 inhibited the IL-2 or IL-2 and IL-4-mediated growth of Th1 and Th2 cells (IC50, 0.08 and 0.02 microM, respectively). Moreover, CGP 41251, but not CGP 42700, inhibited antigen-specific killing of target cells by Th1 clones (IC50 = 0.2 microM), a phenomenon which does not require cell proliferation. When Th1 cells were preincubated with the compound, washed, and rested for 24 hr, they killed the target cells, whereas killing by similarly preincubated, washed, but not rested Th1 cells was inhibited. Thus, the inhibitory effect of CGP 41251 is reversible and excludes the possibility of inhibition due to toxicity at the IC50 dose given. The comparison of CGP 41251 and staurosporine showed that although CGP 41251 has lower activity, it is more specific and much less toxic than staurosporine. Thus, CGP 41251 is more suitable for PKC studies.
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Affiliation(s)
- S S Alkan
- Department of Allergy/Immunology, Ciba-Geigy Ltd., Basel, Switzerland
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Rordorf B, Rutschmann S, Schiess P. Flow tube kinetics of benzocyclobutenedione thermolysis by an automated instrument with integrated GC-ion trap MS analysis. ACTA ACUST UNITED AC 1989. [DOI: 10.1016/0168-1176(89)83041-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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