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2015
Schaeffer Evelyne, Flacher Vincent, Papageorgiou Vasiliki, Decossas Marion, Fauny Jean-Daniel, Krämer Melanie, Mueller Christopher G
Dermal CD14(+) Dendritic Cell and Macrophage Infection by Dengue Virus Is Stimulated by Interleukin-4 Article de journal
Dans: The Journal of Investigative Dermatology, vol. 135, no. 7, p. 1743–1751, 2015, ISSN: 1523-1747.
Résumé | Liens | BibTeX | Étiquettes: Abdominal Wall, Activation, Adhesion, adhesion molecules, Antigen-Presenting Cells, arbovirus, C-Type, Cell Adhesion, Cell Adhesion Molecules, Cell Surface, Cells, Chemistry, Confocal, Cultured, cytokine, Cytokines, cytology, Dendritic Cells, Dengue, Dengue virus, DERMAL DENDRITIC CELLS, Dermatitis, DERMIS, development, disease, Enzyme-Linked Immunosorbent Assay, Epidermal Cells, Epidermis, Human, Humans, ICAM-3, IL-4, Immunology, immunopathology, infection, Interleukin-4, Langerhans Cells, LECTIN, Lectins, Lymphocyte Activation, Macrophage, Macrophages, metabolism, Microscopy, pathogenicity, physiopathology, Receptor, Receptors, Scabies, Sensitivity and Specificity, Skin, Skin Diseases, SUBSETS, T CELL ACTIVATION, target, Team-Mueller, TNF ALPHA, Viral, viral Infection, Viral Load, virology, virus
@article{schaeffer_dermal_2015b,
title = {Dermal CD14(+) Dendritic Cell and Macrophage Infection by Dengue Virus Is Stimulated by Interleukin-4},
author = {Evelyne Schaeffer and Vincent Flacher and Vasiliki Papageorgiou and Marion Decossas and Jean-Daniel Fauny and Melanie Krämer and Christopher G Mueller},
doi = {10.1038/jid.2014.525},
issn = {1523-1747},
year = {2015},
date = {2015-07-01},
journal = {The Journal of Investigative Dermatology},
volume = {135},
number = {7},
pages = {1743--1751},
abstract = {Dengue virus (DENV) is responsible for the most prevalent arthropod-borne viral infection in humans. Events decisive for disease development occur in the skin after virus inoculation by the mosquito. Yet, the role of human dermis-resident immune cells in dengue infection and disease remains elusive. Here we investigated how dermal dendritic cells (dDCs) and macrophages (dMs) react to DENV and impact on immunopathology. We show that both CD1c(+) and CD14(+) dDC subsets were infected, but viral load greatly increased in CD14(+) dDCs upon IL-4 stimulation, which correlated with upregulation of virus-binding lectins Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Nonintegrin (DC-SIGN/CD209) and mannose receptor (CD206). IL-4 also enhanced T-cell activation by dDCs, which was further increased upon dengue infection. dMs purified from digested dermis were initially poorly infected but actively replicated the virus and produced TNF-α upon lectin upregulation in response to IL-4. DC-SIGN(+) cells are abundant in inflammatory skin with scabies infection or Th2-type dermatitis, suggesting that skin reactions to mosquito bites heighten the risk of infection and subsequent immunopathology. Our data identify dDCs and dMs as primary arbovirus target cells in humans and suggest that dDCs initiate a potent virus-directed T-cell response, whereas dMs fuel the inflammatory cascade characteristic of dengue fever.},
keywords = {Abdominal Wall, Activation, Adhesion, adhesion molecules, Antigen-Presenting Cells, arbovirus, C-Type, Cell Adhesion, Cell Adhesion Molecules, Cell Surface, Cells, Chemistry, Confocal, Cultured, cytokine, Cytokines, cytology, Dendritic Cells, Dengue, Dengue virus, DERMAL DENDRITIC CELLS, Dermatitis, DERMIS, development, disease, Enzyme-Linked Immunosorbent Assay, Epidermal Cells, Epidermis, Human, Humans, ICAM-3, IL-4, Immunology, immunopathology, infection, Interleukin-4, Langerhans Cells, LECTIN, Lectins, Lymphocyte Activation, Macrophage, Macrophages, metabolism, Microscopy, pathogenicity, physiopathology, Receptor, Receptors, Scabies, Sensitivity and Specificity, Skin, Skin Diseases, SUBSETS, T CELL ACTIVATION, target, Team-Mueller, TNF ALPHA, Viral, viral Infection, Viral Load, virology, virus},
pubstate = {published},
tppubtype = {article}
}
Dengue virus (DENV) is responsible for the most prevalent arthropod-borne viral infection in humans. Events decisive for disease development occur in the skin after virus inoculation by the mosquito. Yet, the role of human dermis-resident immune cells in dengue infection and disease remains elusive. Here we investigated how dermal dendritic cells (dDCs) and macrophages (dMs) react to DENV and impact on immunopathology. We show that both CD1c(+) and CD14(+) dDC subsets were infected, but viral load greatly increased in CD14(+) dDCs upon IL-4 stimulation, which correlated with upregulation of virus-binding lectins Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Nonintegrin (DC-SIGN/CD209) and mannose receptor (CD206). IL-4 also enhanced T-cell activation by dDCs, which was further increased upon dengue infection. dMs purified from digested dermis were initially poorly infected but actively replicated the virus and produced TNF-α upon lectin upregulation in response to IL-4. DC-SIGN(+) cells are abundant in inflammatory skin with scabies infection or Th2-type dermatitis, suggesting that skin reactions to mosquito bites heighten the risk of infection and subsequent immunopathology. Our data identify dDCs and dMs as primary arbovirus target cells in humans and suggest that dDCs initiate a potent virus-directed T-cell response, whereas dMs fuel the inflammatory cascade characteristic of dengue fever.
Schaeffer Evelyne, Flacher Vincent, Papageorgiou Vasiliki, Decossas Marion, Fauny Jean-Daniel, Krämer Melanie, Mueller Christopher G
Dermal CD14(+) Dendritic Cell and Macrophage Infection by Dengue Virus Is Stimulated by Interleukin-4 Article de journal
Dans: The Journal of Investigative Dermatology, vol. 135, no. 7, p. 1743–1751, 2015, ISSN: 1523-1747.
Résumé | Liens | BibTeX | Étiquettes: Abdominal Wall, Antigen-Presenting Cells, C-Type, Cell Adhesion Molecules, Cell Surface, Cells, Confocal, Cultured, Cytokines, Dengue, Dengue virus, Enzyme-Linked Immunosorbent Assay, Epidermis, Humans, I2CT, Imagerie, Interleukin-4, Langerhans Cells, Lectins, Lymphocyte Activation, Macrophages, Microscopy, Receptors, Sensitivity and Specificity, Skin Diseases, Team-Mueller, Viral
@article{schaeffer_dermal_2015,
title = {Dermal CD14(+) Dendritic Cell and Macrophage Infection by Dengue Virus Is Stimulated by Interleukin-4},
author = {Evelyne Schaeffer and Vincent Flacher and Vasiliki Papageorgiou and Marion Decossas and Jean-Daniel Fauny and Melanie Krämer and Christopher G Mueller},
doi = {10.1038/jid.2014.525},
issn = {1523-1747},
year = {2015},
date = {2015-01-01},
journal = {The Journal of Investigative Dermatology},
volume = {135},
number = {7},
pages = {1743--1751},
abstract = {Dengue virus (DENV) is responsible for the most prevalent arthropod-borne viral infection in humans. Events decisive for disease development occur in the skin after virus inoculation by the mosquito. Yet, the role of human dermis-resident immune cells in dengue infection and disease remains elusive. Here we investigated how dermal dendritic cells (dDCs) and macrophages (dMs) react to DENV and impact on immunopathology. We show that both CD1c(+) and CD14(+) dDC subsets were infected, but viral load greatly increased in CD14(+) dDCs upon IL-4 stimulation, which correlated with upregulation of virus-binding lectins Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Nonintegrin (DC-SIGN/CD209) and mannose receptor (CD206). IL-4 also enhanced T-cell activation by dDCs, which was further increased upon dengue infection. dMs purified from digested dermis were initially poorly infected but actively replicated the virus and produced TNF-α upon lectin upregulation in response to IL-4. DC-SIGN(+) cells are abundant in inflammatory skin with scabies infection or Th2-type dermatitis, suggesting that skin reactions to mosquito bites heighten the risk of infection and subsequent immunopathology. Our data identify dDCs and dMs as primary arbovirus target cells in humans and suggest that dDCs initiate a potent virus-directed T-cell response, whereas dMs fuel the inflammatory cascade characteristic of dengue fever.},
keywords = {Abdominal Wall, Antigen-Presenting Cells, C-Type, Cell Adhesion Molecules, Cell Surface, Cells, Confocal, Cultured, Cytokines, Dengue, Dengue virus, Enzyme-Linked Immunosorbent Assay, Epidermis, Humans, I2CT, Imagerie, Interleukin-4, Langerhans Cells, Lectins, Lymphocyte Activation, Macrophages, Microscopy, Receptors, Sensitivity and Specificity, Skin Diseases, Team-Mueller, Viral},
pubstate = {published},
tppubtype = {article}
}
Dengue virus (DENV) is responsible for the most prevalent arthropod-borne viral infection in humans. Events decisive for disease development occur in the skin after virus inoculation by the mosquito. Yet, the role of human dermis-resident immune cells in dengue infection and disease remains elusive. Here we investigated how dermal dendritic cells (dDCs) and macrophages (dMs) react to DENV and impact on immunopathology. We show that both CD1c(+) and CD14(+) dDC subsets were infected, but viral load greatly increased in CD14(+) dDCs upon IL-4 stimulation, which correlated with upregulation of virus-binding lectins Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Nonintegrin (DC-SIGN/CD209) and mannose receptor (CD206). IL-4 also enhanced T-cell activation by dDCs, which was further increased upon dengue infection. dMs purified from digested dermis were initially poorly infected but actively replicated the virus and produced TNF-α upon lectin upregulation in response to IL-4. DC-SIGN(+) cells are abundant in inflammatory skin with scabies infection or Th2-type dermatitis, suggesting that skin reactions to mosquito bites heighten the risk of infection and subsequent immunopathology. Our data identify dDCs and dMs as primary arbovirus target cells in humans and suggest that dDCs initiate a potent virus-directed T-cell response, whereas dMs fuel the inflammatory cascade characteristic of dengue fever.
2012
Flacher V, Tripp C H, Haid B, Kissenpfennig A, Malissen B, Stoitzner P, Idoyaga J, Romani N
Skin langerin+ dendritic cells transport intradermally injected anti-DEC-205 antibodies but are not essential for subsequent cytotoxic CD8+ Ŧ cell responses Article de journal
Dans: Journal of Immunology, vol. 188, no. 1550-6606 (Electronic), p. 2146–2155, 2012.
Résumé | BibTeX | Étiquettes: administration & dosage, Animals, Antibodies, antibody, Antigen, Antigens, Biosynthesis, C-Type, C-type lectin, CD, Cell Surface, Comparative Study, Cytotoxic, Dendritic Cells, DERMATOLOGY, Gene Knock-In Techniques, Genetics, imiquimod, immune response, IMMUNE-RESPONSES, Immunization, Immunology, in situ, In vivo, Inbred BALB C, Inbred C57BL, INDUCTION, inflammation, Inflammation Mediators, Injections, Intradermal, knock-in, Langerhans Cells, LECTIN, Lectins, LYMPH, LYMPH NODE, Lymph Nodes, LYMPHATIC VESSEL, Lymphatic Vessels, mAb, Mannose-Binding Lectins, MEDIATOR, metabolism, Mice, Minor Histocompatibility Antigens, mouse, murine, Organ Culture Techniques, Ovum, pathology, physiology, Protein, Protein Transport, Rats, Receptor, Receptors, RESPONSES, Skin, SUBSETS, Surface, T-Lymphocytes, target, Team-Mueller, TLR7, transgenic
@article{flacher_skin_2012,
title = {Skin langerin+ dendritic cells transport intradermally injected anti-DEC-205 antibodies but are not essential for subsequent cytotoxic CD8+ Ŧ cell responses},
author = {V Flacher and C H Tripp and B Haid and A Kissenpfennig and B Malissen and P Stoitzner and J Idoyaga and N Romani},
year = {2012},
date = {2012-03-01},
journal = {Journal of Immunology},
volume = {188},
number = {1550-6606 (Electronic)},
pages = {2146--2155},
abstract = {Incorporation of Ags by dendritic cells (DCs) increases when Ags are targeted to endocytic receptors by mAbs. We have previously demonstrated in the mouse that mAbs against C-type lectins administered intradermally are taken up by epidermal Langerhans cells (LCs), dermal Langerin(neg) DCs, and dermal Langerin(+) DCs in situ. However, the relative contribution of these skin DC subsets to the induction of immune responses after Ag targeting has not been addressed in vivo. We show in this study that murine epidermal LCs and dermal DCs transport intradermally injected mAbs against the lectin receptor DEC-205/CD205 in vivo. Skin DCs targeted in situ with mAbs migrated through lymphatic vessels in steady state and inflammation. In the skin-draining lymph nodes, targeting mAbs were found in resident CD8alpha(+) DCs and in migrating skin DCs. More than 70% of targeted DCs expressed Langerin, including dermal Langerin(+) DCs and LCs. Numbers of targeted skin DCs in the nodes increased 2-3-fold when skin was topically inflamed by the TLR7 agonist imiquimod. Complete removal of the site where OVA-coupled anti-DEC-205 had been injected decreased endogenous cytotoxic responses against OVA peptide-loaded target cells by 40-50%. Surprisingly, selective ablation of all Langerin(+) skin DCs in Langerin-DTR knock-in mice did not affect such responses independently of the adjuvant chosen. Thus, in cutaneous immunization strategies where Ag is targeted to DCs, Langerin(+) skin DCs play a major role in transport of anti-DEC-205 mAb, although Langerin(neg) dermal DCs and CD8alpha(+) DCs are sufficient to subsequent CD8(+) T cell responses},
keywords = {administration & dosage, Animals, Antibodies, antibody, Antigen, Antigens, Biosynthesis, C-Type, C-type lectin, CD, Cell Surface, Comparative Study, Cytotoxic, Dendritic Cells, DERMATOLOGY, Gene Knock-In Techniques, Genetics, imiquimod, immune response, IMMUNE-RESPONSES, Immunization, Immunology, in situ, In vivo, Inbred BALB C, Inbred C57BL, INDUCTION, inflammation, Inflammation Mediators, Injections, Intradermal, knock-in, Langerhans Cells, LECTIN, Lectins, LYMPH, LYMPH NODE, Lymph Nodes, LYMPHATIC VESSEL, Lymphatic Vessels, mAb, Mannose-Binding Lectins, MEDIATOR, metabolism, Mice, Minor Histocompatibility Antigens, mouse, murine, Organ Culture Techniques, Ovum, pathology, physiology, Protein, Protein Transport, Rats, Receptor, Receptors, RESPONSES, Skin, SUBSETS, Surface, T-Lymphocytes, target, Team-Mueller, TLR7, transgenic},
pubstate = {published},
tppubtype = {article}
}
Incorporation of Ags by dendritic cells (DCs) increases when Ags are targeted to endocytic receptors by mAbs. We have previously demonstrated in the mouse that mAbs against C-type lectins administered intradermally are taken up by epidermal Langerhans cells (LCs), dermal Langerin(neg) DCs, and dermal Langerin(+) DCs in situ. However, the relative contribution of these skin DC subsets to the induction of immune responses after Ag targeting has not been addressed in vivo. We show in this study that murine epidermal LCs and dermal DCs transport intradermally injected mAbs against the lectin receptor DEC-205/CD205 in vivo. Skin DCs targeted in situ with mAbs migrated through lymphatic vessels in steady state and inflammation. In the skin-draining lymph nodes, targeting mAbs were found in resident CD8alpha(+) DCs and in migrating skin DCs. More than 70% of targeted DCs expressed Langerin, including dermal Langerin(+) DCs and LCs. Numbers of targeted skin DCs in the nodes increased 2-3-fold when skin was topically inflamed by the TLR7 agonist imiquimod. Complete removal of the site where OVA-coupled anti-DEC-205 had been injected decreased endogenous cytotoxic responses against OVA peptide-loaded target cells by 40-50%. Surprisingly, selective ablation of all Langerin(+) skin DCs in Langerin-DTR knock-in mice did not affect such responses independently of the adjuvant chosen. Thus, in cutaneous immunization strategies where Ag is targeted to DCs, Langerin(+) skin DCs play a major role in transport of anti-DEC-205 mAb, although Langerin(neg) dermal DCs and CD8alpha(+) DCs are sufficient to subsequent CD8(+) T cell responses
2011
Nehme Nadine T, Quintin Jessica, Cho Ju Hyun, Lee Janice, Lafarge Marie-Céline, Kocks Christine, Ferrandon Dominique
Relative roles of the cellular and humoral responses in the Drosophila host defense against three gram-positive bacterial infections Article de journal
Dans: PLoS ONE, vol. 6, no. 3, p. e14743, 2011, ISSN: 1932-6203.
Résumé | Liens | BibTeX | Étiquettes: Animals, Antimicrobial Cationic Peptides, Carrier Proteins, Cell Surface, Cellular, Enterococcus faecalis, ferrandon, Gram-Positive Bacteria, Gram-Positive Bacterial Infections, Host-Pathogen Interactions, Humoral, Immunity, Innate, M3i, Micrococcus luteus, Opsonin Proteins, Phagocytosis, Receptors, Signal Transduction, Solubility, Staphylococcus aureus
@article{nehme_relative_2011b,
title = {Relative roles of the cellular and humoral responses in the Drosophila host defense against three gram-positive bacterial infections},
author = {Nadine T Nehme and Jessica Quintin and Ju Hyun Cho and Janice Lee and Marie-Céline Lafarge and Christine Kocks and Dominique Ferrandon},
doi = {10.1371/journal.pone.0014743},
issn = {1932-6203},
year = {2011},
date = {2011-01-01},
journal = {PLoS ONE},
volume = {6},
number = {3},
pages = {e14743},
abstract = {BACKGROUND: Two NF-kappaB signaling pathways, Toll and immune deficiency (imd), are required for survival to bacterial infections in Drosophila. In response to septic injury, these pathways mediate rapid transcriptional activation of distinct sets of effector molecules, including antimicrobial peptides, which are important components of a humoral defense response. However, it is less clear to what extent macrophage-like hemocytes contribute to host defense. METHODOLOGY/PRINCIPAL FINDINGS: In order to dissect the relative importance of humoral and cellular defenses after septic injury with three different gram-positive bacteria (Micrococcus luteus, Enterococcus faecalis, Staphylococcus aureus), we used latex bead pre-injection to ablate macrophage function in flies wildtype or mutant for various Toll and imd pathway components. We found that in all three infection models a compromised phagocytic system impaired fly survival--independently of concomitant Toll or imd pathway activation. Our data failed to confirm a role of the PGRP-SA and GNBP1 Pattern Recognition Receptors for phagocytosis of S. aureus. The Drosophila scavenger receptor Eater mediates the phagocytosis by hemocytes or S2 cells of E. faecalis and S. aureus, but not of M. luteus. In the case of M. luteus and E. faecalis, but not S. aureus, decreased survival due to defective phagocytosis could be compensated for by genetically enhancing the humoral immune response. CONCLUSIONS/SIGNIFICANCE: Our results underscore the fundamental importance of both cellular and humoral mechanisms in Drosophila immunity and shed light on the balance between these two arms of host defense depending on the invading pathogen.},
keywords = {Animals, Antimicrobial Cationic Peptides, Carrier Proteins, Cell Surface, Cellular, Enterococcus faecalis, ferrandon, Gram-Positive Bacteria, Gram-Positive Bacterial Infections, Host-Pathogen Interactions, Humoral, Immunity, Innate, M3i, Micrococcus luteus, Opsonin Proteins, Phagocytosis, Receptors, Signal Transduction, Solubility, Staphylococcus aureus},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: Two NF-kappaB signaling pathways, Toll and immune deficiency (imd), are required for survival to bacterial infections in Drosophila. In response to septic injury, these pathways mediate rapid transcriptional activation of distinct sets of effector molecules, including antimicrobial peptides, which are important components of a humoral defense response. However, it is less clear to what extent macrophage-like hemocytes contribute to host defense. METHODOLOGY/PRINCIPAL FINDINGS: In order to dissect the relative importance of humoral and cellular defenses after septic injury with three different gram-positive bacteria (Micrococcus luteus, Enterococcus faecalis, Staphylococcus aureus), we used latex bead pre-injection to ablate macrophage function in flies wildtype or mutant for various Toll and imd pathway components. We found that in all three infection models a compromised phagocytic system impaired fly survival--independently of concomitant Toll or imd pathway activation. Our data failed to confirm a role of the PGRP-SA and GNBP1 Pattern Recognition Receptors for phagocytosis of S. aureus. The Drosophila scavenger receptor Eater mediates the phagocytosis by hemocytes or S2 cells of E. faecalis and S. aureus, but not of M. luteus. In the case of M. luteus and E. faecalis, but not S. aureus, decreased survival due to defective phagocytosis could be compensated for by genetically enhancing the humoral immune response. CONCLUSIONS/SIGNIFICANCE: Our results underscore the fundamental importance of both cellular and humoral mechanisms in Drosophila immunity and shed light on the balance between these two arms of host defense depending on the invading pathogen.
Canard B, Vachon H, Fontaine T, Pin J J, Paul S, Genin C, Mueller C G
Generation of anti-DC-SIGN monoclonal antibodies capable of blocking HIV-1 gp120 binding and reactive on formalin-fixed tissue Article de journal
Dans: Immunol.Lett., vol. 135, no. 1879-0542 (Electronic), p. 165–172, 2011.
Résumé | BibTeX | Étiquettes: Adhesion, adhesion molecules, Animals, Antibodies, antibody, Antigen, Antigens, Blocking, C-Type, C-type lectin, CD, Cell Adhesion, Cell Adhesion Molecules, Cell Surface, Chemistry, clones, Dendritic Cells, DERMIS, Differentiation, Fixatives, Formaldehyde, formalin-fixed tissue, Genetics, GLYCOPROTEIN, GP120, HeLa Cells, HIV, HIV Envelope Protein gp120, HIV-1, Human, Humans, hybridoma, ICAM-3, immunodeficiency, Immunology, Inbred BALB C, infection, LECTIN, Lectins, Macrophage, Macrophages, Mice, Monoclonal, monoclonal antibody, MONOCLONAL-ANTIBODY, Monocytes, Murine-Derived, Myelomonocytic, Nih 3T3 Cells, Paraffin Embedding, pathogenicity, Protein, Receptor, Receptors, recognition, Skin, Team-Mueller, virus
@article{canard_generation_2011,
title = {Generation of anti-DC-SIGN monoclonal antibodies capable of blocking HIV-1 gp120 binding and reactive on formalin-fixed tissue},
author = {B Canard and H Vachon and T Fontaine and J J Pin and S Paul and C Genin and C G Mueller},
year = {2011},
date = {2011-01-01},
journal = {Immunol.Lett.},
volume = {135},
number = {1879-0542 (Electronic)},
pages = {165--172},
abstract = {DC-SIGN is a C-type lectin of recognized importance in immunology and in the pathogenicity human pathogens. Monoclonal antibodies directed against DC-SIGN have been generated, but their systemic characterization for interfering with binding of the HIV-1 glycoprotein 120 has often been omitted. Moreover, so far, no anti-DC-SIGN monoclonal antibody has been described that recognizes its antigen after formalin fixation and paraffin embedding. In this study, we have generated new anti-DC-SIGN monoclonal antibodies using HeLa cells stably expressing DC-SIGN as immunogen. We have obtained 11 hybridoma clones producing antibodies that recognized DC-SIGN on monocyte-derived dendritic cells and on dermal-type macrophages. Seven monoclonal antibodies displayed a capacity to interfere with DC-SIGN binding to HIV-1 gp120. One recognized DC-SIGN on formalin-fixed dendritic cells and macrophages. Using this antibody we have obtained specific labelling of DC-SIGN and colocalisation with the dermal macrophage marker CD163 on human skin. The described monoclonal anti-human DC-SIGN antibodies will be of use to the scientific community to address fundamental immunology issues, in particular concerning macrophages and dendritic cells, and help elucidate infection events of pathogen targeting DC-SIGN as recognition receptor},
keywords = {Adhesion, adhesion molecules, Animals, Antibodies, antibody, Antigen, Antigens, Blocking, C-Type, C-type lectin, CD, Cell Adhesion, Cell Adhesion Molecules, Cell Surface, Chemistry, clones, Dendritic Cells, DERMIS, Differentiation, Fixatives, Formaldehyde, formalin-fixed tissue, Genetics, GLYCOPROTEIN, GP120, HeLa Cells, HIV, HIV Envelope Protein gp120, HIV-1, Human, Humans, hybridoma, ICAM-3, immunodeficiency, Immunology, Inbred BALB C, infection, LECTIN, Lectins, Macrophage, Macrophages, Mice, Monoclonal, monoclonal antibody, MONOCLONAL-ANTIBODY, Monocytes, Murine-Derived, Myelomonocytic, Nih 3T3 Cells, Paraffin Embedding, pathogenicity, Protein, Receptor, Receptors, recognition, Skin, Team-Mueller, virus},
pubstate = {published},
tppubtype = {article}
}
DC-SIGN is a C-type lectin of recognized importance in immunology and in the pathogenicity human pathogens. Monoclonal antibodies directed against DC-SIGN have been generated, but their systemic characterization for interfering with binding of the HIV-1 glycoprotein 120 has often been omitted. Moreover, so far, no anti-DC-SIGN monoclonal antibody has been described that recognizes its antigen after formalin fixation and paraffin embedding. In this study, we have generated new anti-DC-SIGN monoclonal antibodies using HeLa cells stably expressing DC-SIGN as immunogen. We have obtained 11 hybridoma clones producing antibodies that recognized DC-SIGN on monocyte-derived dendritic cells and on dermal-type macrophages. Seven monoclonal antibodies displayed a capacity to interfere with DC-SIGN binding to HIV-1 gp120. One recognized DC-SIGN on formalin-fixed dendritic cells and macrophages. Using this antibody we have obtained specific labelling of DC-SIGN and colocalisation with the dermal macrophage marker CD163 on human skin. The described monoclonal anti-human DC-SIGN antibodies will be of use to the scientific community to address fundamental immunology issues, in particular concerning macrophages and dendritic cells, and help elucidate infection events of pathogen targeting DC-SIGN as recognition receptor
2010
den Bossche Jeroen Van, Al-Jamal Wafa' T, Tian Bowen, Nunes Antonio, Fabbro Chiara, Bianco Alberto, Prato Maurizio, Kostarelos Kostas
Efficient receptor-independent intracellular translocation of aptamers mediated by conjugation to carbon nanotubes Article de journal
Dans: Chemical Communications (Cambridge, England), vol. 46, no. 39, p. 7379–7381, 2010, ISSN: 1364-548X.
Résumé | Liens | BibTeX | Étiquettes: Aptamers, Base Sequence, Biological Transport, carbon, Cell Line, Cell Surface, DNA Primers, Electron, Electrophoresis, Humans, I2CT, Microscopy, Nanotubes, Nucleotide, Polyacrylamide Gel, Receptors, Team-Bianco, Transmission, tumor
@article{van_den_bossche_efficient_2010,
title = {Efficient receptor-independent intracellular translocation of aptamers mediated by conjugation to carbon nanotubes},
author = {Jeroen Van den Bossche and Wafa' T Al-Jamal and Bowen Tian and Antonio Nunes and Chiara Fabbro and Alberto Bianco and Maurizio Prato and Kostas Kostarelos},
doi = {10.1039/c0cc02092c},
issn = {1364-548X},
year = {2010},
date = {2010-10-01},
journal = {Chemical Communications (Cambridge, England)},
volume = {46},
number = {39},
pages = {7379--7381},
abstract = {We have covalently grafted aptamers onto carboxylated carbon nanotubes to design a novel vector system that can easily translocate into the cytosol of different cell types independent of receptor-mediated uptake. We propose the use of carbon nanotubes for the efficient intracellular delivery of biologically active aptamers for potential therapeutic applications.},
keywords = {Aptamers, Base Sequence, Biological Transport, carbon, Cell Line, Cell Surface, DNA Primers, Electron, Electrophoresis, Humans, I2CT, Microscopy, Nanotubes, Nucleotide, Polyacrylamide Gel, Receptors, Team-Bianco, Transmission, tumor},
pubstate = {published},
tppubtype = {article}
}
We have covalently grafted aptamers onto carboxylated carbon nanotubes to design a novel vector system that can easily translocate into the cytosol of different cell types independent of receptor-mediated uptake. We propose the use of carbon nanotubes for the efficient intracellular delivery of biologically active aptamers for potential therapeutic applications.
2008
Kwan Wing-Hong, Navarro-Sanchez Erika, Dumortier Hélène, Decossas Marion, Vachon Hortense, dos Santos Flavia Barreto, Fridman Hervé W, Rey Félix A, Harris Eva, Despres Philippe, Mueller Christopher G
Dermal-type macrophages expressing CD209/DC-SIGN show inherent resistance to dengue virus growth Article de journal
Dans: PLoS neglected tropical diseases, vol. 2, no. 10, p. e311, 2008, ISSN: 1935-2735.
Résumé | Liens | BibTeX | Étiquettes: Adhesion, adhesion molecules, C-Type, Cell Adhesion, Cell Adhesion Molecules, Cell Line, Cell Surface, Cells, Chemistry, Cultured, Dendritic Cells, Dengue, Dengue virus, Gene Expression, Genetics, GLYCOPROTEIN, Growth, growth & development, Humans, ICAM-3, IFN ALPHA, IL-10, IL10, IMMATURE, Immunology, in situ, infection, LECTIN, Lectins, Macrophage, Macrophages, metabolism, METHOD, methods, monocyte, Monocytes, myeloid dendritic cells, pathogenesis, Phagosomes, PRODUCTION, Protein, Protein Binding, Proteins, Receptor, Receptors, Resistance, Skin, Team-Mueller, Viral Envelope Proteins, virology, virus
@article{kwan_dermal-type_2008b,
title = {Dermal-type macrophages expressing CD209/DC-SIGN show inherent resistance to dengue virus growth},
author = {Wing-Hong Kwan and Erika Navarro-Sanchez and Hélène Dumortier and Marion Decossas and Hortense Vachon and Flavia Barreto dos Santos and Hervé W Fridman and Félix A Rey and Eva Harris and Philippe Despres and Christopher G Mueller},
doi = {10.1371/journal.pntd.0000311},
issn = {1935-2735},
year = {2008},
date = {2008-10-01},
journal = {PLoS neglected tropical diseases},
volume = {2},
number = {10},
pages = {e311},
abstract = {BACKGROUND: An important question in dengue pathogenesis is the identity of immune cells involved in the control of dengue virus infection at the site of the mosquito bite. There is evidence that infection of immature myeloid dendritic cells plays a crucial role in dengue pathogenesis and that the interaction of the viral envelope E glycoprotein with CD209/DC-SIGN is a key element for their productive infection. Dermal macrophages express CD209, yet little is known about their role in dengue virus infection.
METHODS AND FINDINGS: Here, we showed that dermal macrophages bound recombinant envelope E glycoprotein fused to green fluorescent protein. Because dermal macrophages stain for IL-10 in situ, we generated dermal-type macrophages from monocytes in the presence of IL-10 to study their infection by dengue virus. The macrophages were able to internalize the virus, but progeny virus production was undetectable in the infected cells. In addition, no IFN-alpha was produced in response to the virus. The inability of dengue virus to grow in the macrophages was attributable to accumulation of internalized virus particles into poorly-acidified phagosomes.
CONCLUSIONS: Aborting infection by viral sequestration in early phagosomes would present a novel means to curb infection of enveloped virus and may constitute a prime defense system to prevent dengue virus spread shortly after the bite of the infected mosquito.},
keywords = {Adhesion, adhesion molecules, C-Type, Cell Adhesion, Cell Adhesion Molecules, Cell Line, Cell Surface, Cells, Chemistry, Cultured, Dendritic Cells, Dengue, Dengue virus, Gene Expression, Genetics, GLYCOPROTEIN, Growth, growth & development, Humans, ICAM-3, IFN ALPHA, IL-10, IL10, IMMATURE, Immunology, in situ, infection, LECTIN, Lectins, Macrophage, Macrophages, metabolism, METHOD, methods, monocyte, Monocytes, myeloid dendritic cells, pathogenesis, Phagosomes, PRODUCTION, Protein, Protein Binding, Proteins, Receptor, Receptors, Resistance, Skin, Team-Mueller, Viral Envelope Proteins, virology, virus},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: An important question in dengue pathogenesis is the identity of immune cells involved in the control of dengue virus infection at the site of the mosquito bite. There is evidence that infection of immature myeloid dendritic cells plays a crucial role in dengue pathogenesis and that the interaction of the viral envelope E glycoprotein with CD209/DC-SIGN is a key element for their productive infection. Dermal macrophages express CD209, yet little is known about their role in dengue virus infection.
METHODS AND FINDINGS: Here, we showed that dermal macrophages bound recombinant envelope E glycoprotein fused to green fluorescent protein. Because dermal macrophages stain for IL-10 in situ, we generated dermal-type macrophages from monocytes in the presence of IL-10 to study their infection by dengue virus. The macrophages were able to internalize the virus, but progeny virus production was undetectable in the infected cells. In addition, no IFN-alpha was produced in response to the virus. The inability of dengue virus to grow in the macrophages was attributable to accumulation of internalized virus particles into poorly-acidified phagosomes.
CONCLUSIONS: Aborting infection by viral sequestration in early phagosomes would present a novel means to curb infection of enveloped virus and may constitute a prime defense system to prevent dengue virus spread shortly after the bite of the infected mosquito.
METHODS AND FINDINGS: Here, we showed that dermal macrophages bound recombinant envelope E glycoprotein fused to green fluorescent protein. Because dermal macrophages stain for IL-10 in situ, we generated dermal-type macrophages from monocytes in the presence of IL-10 to study their infection by dengue virus. The macrophages were able to internalize the virus, but progeny virus production was undetectable in the infected cells. In addition, no IFN-alpha was produced in response to the virus. The inability of dengue virus to grow in the macrophages was attributable to accumulation of internalized virus particles into poorly-acidified phagosomes.
CONCLUSIONS: Aborting infection by viral sequestration in early phagosomes would present a novel means to curb infection of enveloped virus and may constitute a prime defense system to prevent dengue virus spread shortly after the bite of the infected mosquito.
Flacher Vincent, Douillard Patrice, Aït-Yahia Smina, Stoitzner Patrizia, Clair-Moninot Valérie, Romani Nikolaus, Saeland Sem
Expression of langerin/CD207 reveals dendritic cell heterogeneity between inbred mouse strains Article de journal
Dans: Immunology, vol. 123, no. 3, p. 339–347, 2008, ISSN: 1365-2567.
Résumé | Liens | BibTeX | Étiquettes: Animals, Antigen, Antigens, C-Type, CD, Cell Surface, Dendritic Cells, DERMATOLOGY, Epidermis, Expression, Immunology, Immunophenotyping, Inbred Strains, inflammation, Langerhans Cells, LECTIN, Lectins, LYMPH, LYMPH NODE, Lymph Nodes, Lymphoid Tissue, Mannose-Binding Lectins, Maturation, metabolism, Mice, Minor Histocompatibility Antigens, mouse, Phenotype, Protein, Receptor, Receptors, Species Specificity, SPLEEN, SUBSETS, Surface, Team-Mueller
@article{flacher_expression_2008,
title = {Expression of langerin/CD207 reveals dendritic cell heterogeneity between inbred mouse strains},
author = {Vincent Flacher and Patrice Douillard and Smina Aït-Yahia and Patrizia Stoitzner and Valérie Clair-Moninot and Nikolaus Romani and Sem Saeland},
doi = {10.1111/j.1365-2567.2007.02785.x},
issn = {1365-2567},
year = {2008},
date = {2008-03-01},
journal = {Immunology},
volume = {123},
number = {3},
pages = {339--347},
abstract = {Langerin/CD207 is expressed by a subset of dendritic cells (DC), the epithelial Langerhans cells. However, langerin is also detected among lymphoid tissue DC. Here, we describe striking differences in langerin-expressing cells between inbred mouse strains. While langerin+ cells are observed in comparable numbers and with comparable phenotypes in the epidermis, two distinct DC subsets bear langerin in peripheral, skin-draining lymph nodes of BALB/c mice (CD11c(high) CD8alpha(high) and CD11c(low) CD8alpha(low)), whereas only the latter subset is present in C57BL/6 mice. The CD11c(high) subset is detected in mesenteric lymph nodes and spleen of BALB/c mice, but is virtually absent from C57BL/6 mice. Similar differences are observed in other mouse strains. CD11c(low) langerin+ cells represent skin-derived Langerhans cells, as demonstrated by their high expression of DEC-205/CD205, maturation markers, and recruitment to skin-draining lymph nodes upon imiquimod-induced inflammation. It will be of interest to determine the role of lymphoid tissue-resident compared to skin-derived langerin+ DC.},
keywords = {Animals, Antigen, Antigens, C-Type, CD, Cell Surface, Dendritic Cells, DERMATOLOGY, Epidermis, Expression, Immunology, Immunophenotyping, Inbred Strains, inflammation, Langerhans Cells, LECTIN, Lectins, LYMPH, LYMPH NODE, Lymph Nodes, Lymphoid Tissue, Mannose-Binding Lectins, Maturation, metabolism, Mice, Minor Histocompatibility Antigens, mouse, Phenotype, Protein, Receptor, Receptors, Species Specificity, SPLEEN, SUBSETS, Surface, Team-Mueller},
pubstate = {published},
tppubtype = {article}
}
Langerin/CD207 is expressed by a subset of dendritic cells (DC), the epithelial Langerhans cells. However, langerin is also detected among lymphoid tissue DC. Here, we describe striking differences in langerin-expressing cells between inbred mouse strains. While langerin+ cells are observed in comparable numbers and with comparable phenotypes in the epidermis, two distinct DC subsets bear langerin in peripheral, skin-draining lymph nodes of BALB/c mice (CD11c(high) CD8alpha(high) and CD11c(low) CD8alpha(low)), whereas only the latter subset is present in C57BL/6 mice. The CD11c(high) subset is detected in mesenteric lymph nodes and spleen of BALB/c mice, but is virtually absent from C57BL/6 mice. Similar differences are observed in other mouse strains. CD11c(low) langerin+ cells represent skin-derived Langerhans cells, as demonstrated by their high expression of DEC-205/CD205, maturation markers, and recruitment to skin-draining lymph nodes upon imiquimod-induced inflammation. It will be of interest to determine the role of lymphoid tissue-resident compared to skin-derived langerin+ DC.
Kwan Wing-Hong, Navarro-Sanchez Erika, Dumortier Hélène, Decossas Marion, Vachon Hortense, dos Santos Flavia Barreto, Fridman Hervé W, Rey Félix A, Harris Eva, Despres Philippe, Mueller Christopher G
Dermal-type macrophages expressing CD209/DC-SIGN show inherent resistance to dengue virus growth Article de journal
Dans: PLoS neglected tropical diseases, vol. 2, no. 10, p. e311, 2008, ISSN: 1935-2735.
Résumé | Liens | BibTeX | Étiquettes: C-Type, Cell Adhesion Molecules, Cell Line, Cell Surface, Cells, Cultured, Dengue, Dengue virus, Dumortier, Gene Expression, Humans, I2CT, Lectins, Macrophages, Protein Binding, Receptors, Skin, Team-Dumortier, Team-Mueller, Viral Envelope Proteins
@article{kwan_dermal-type_2008,
title = {Dermal-type macrophages expressing CD209/DC-SIGN show inherent resistance to dengue virus growth},
author = {Wing-Hong Kwan and Erika Navarro-Sanchez and Hélène Dumortier and Marion Decossas and Hortense Vachon and Flavia Barreto dos Santos and Hervé W Fridman and Félix A Rey and Eva Harris and Philippe Despres and Christopher G Mueller},
doi = {10.1371/journal.pntd.0000311},
issn = {1935-2735},
year = {2008},
date = {2008-01-01},
journal = {PLoS neglected tropical diseases},
volume = {2},
number = {10},
pages = {e311},
abstract = {BACKGROUND: An important question in dengue pathogenesis is the identity of immune cells involved in the control of dengue virus infection at the site of the mosquito bite. There is evidence that infection of immature myeloid dendritic cells plays a crucial role in dengue pathogenesis and that the interaction of the viral envelope E glycoprotein with CD209/DC-SIGN is a key element for their productive infection. Dermal macrophages express CD209, yet little is known about their role in dengue virus infection.
METHODS AND FINDINGS: Here, we showed that dermal macrophages bound recombinant envelope E glycoprotein fused to green fluorescent protein. Because dermal macrophages stain for IL-10 in situ, we generated dermal-type macrophages from monocytes in the presence of IL-10 to study their infection by dengue virus. The macrophages were able to internalize the virus, but progeny virus production was undetectable in the infected cells. In addition, no IFN-alpha was produced in response to the virus. The inability of dengue virus to grow in the macrophages was attributable to accumulation of internalized virus particles into poorly-acidified phagosomes.
CONCLUSIONS: Aborting infection by viral sequestration in early phagosomes would present a novel means to curb infection of enveloped virus and may constitute a prime defense system to prevent dengue virus spread shortly after the bite of the infected mosquito.},
keywords = {C-Type, Cell Adhesion Molecules, Cell Line, Cell Surface, Cells, Cultured, Dengue, Dengue virus, Dumortier, Gene Expression, Humans, I2CT, Lectins, Macrophages, Protein Binding, Receptors, Skin, Team-Dumortier, Team-Mueller, Viral Envelope Proteins},
pubstate = {published},
tppubtype = {article}
}
BACKGROUND: An important question in dengue pathogenesis is the identity of immune cells involved in the control of dengue virus infection at the site of the mosquito bite. There is evidence that infection of immature myeloid dendritic cells plays a crucial role in dengue pathogenesis and that the interaction of the viral envelope E glycoprotein with CD209/DC-SIGN is a key element for their productive infection. Dermal macrophages express CD209, yet little is known about their role in dengue virus infection.
METHODS AND FINDINGS: Here, we showed that dermal macrophages bound recombinant envelope E glycoprotein fused to green fluorescent protein. Because dermal macrophages stain for IL-10 in situ, we generated dermal-type macrophages from monocytes in the presence of IL-10 to study their infection by dengue virus. The macrophages were able to internalize the virus, but progeny virus production was undetectable in the infected cells. In addition, no IFN-alpha was produced in response to the virus. The inability of dengue virus to grow in the macrophages was attributable to accumulation of internalized virus particles into poorly-acidified phagosomes.
CONCLUSIONS: Aborting infection by viral sequestration in early phagosomes would present a novel means to curb infection of enveloped virus and may constitute a prime defense system to prevent dengue virus spread shortly after the bite of the infected mosquito.
METHODS AND FINDINGS: Here, we showed that dermal macrophages bound recombinant envelope E glycoprotein fused to green fluorescent protein. Because dermal macrophages stain for IL-10 in situ, we generated dermal-type macrophages from monocytes in the presence of IL-10 to study their infection by dengue virus. The macrophages were able to internalize the virus, but progeny virus production was undetectable in the infected cells. In addition, no IFN-alpha was produced in response to the virus. The inability of dengue virus to grow in the macrophages was attributable to accumulation of internalized virus particles into poorly-acidified phagosomes.
CONCLUSIONS: Aborting infection by viral sequestration in early phagosomes would present a novel means to curb infection of enveloped virus and may constitute a prime defense system to prevent dengue virus spread shortly after the bite of the infected mosquito.
2005
Kocks Christine, Cho Ju Hyun, Nehme Nadine, Ulvila Johanna, Pearson Alan M, Meister Marie, Strom Charles, Conto Stephanie L, Hetru Charles, Stuart Lynda M, Stehle Thilo, Hoffmann Jules A, Reichhart Jean-Marc, Ferrandon Dominique, Rämet Mika, Ezekowitz Alan R B
Eater, a transmembrane protein mediating phagocytosis of bacterial pathogens in Drosophila Article de journal
Dans: Cell, vol. 123, no. 2, p. 335–346, 2005, ISSN: 0092-8674.
Résumé | Liens | BibTeX | Étiquettes: Amino Acid, Amino Acid Motifs, Animals, Bacterial Infections, Cell Surface, Embryo, Escherichia coli, ferrandon, Flow Cytometry, Frameshift Mutation, Genes, Histidine, hoffmann, In Situ Hybridization, Insect, Insect Proteins, M3i, Macrophages, Membrane Proteins, messenger, Nonmammalian, Open Reading Frames, Phagocytosis, Receptors, reichhart, RNA, RNA Interference, Sequence Homology, Serratia marcescens
@article{kocks_eater_2005,
title = {Eater, a transmembrane protein mediating phagocytosis of bacterial pathogens in Drosophila},
author = {Christine Kocks and Ju Hyun Cho and Nadine Nehme and Johanna Ulvila and Alan M Pearson and Marie Meister and Charles Strom and Stephanie L Conto and Charles Hetru and Lynda M Stuart and Thilo Stehle and Jules A Hoffmann and Jean-Marc Reichhart and Dominique Ferrandon and Mika Rämet and Alan R B Ezekowitz},
doi = {10.1016/j.cell.2005.08.034},
issn = {0092-8674},
year = {2005},
date = {2005-10-01},
journal = {Cell},
volume = {123},
number = {2},
pages = {335--346},
abstract = {Phagocytosis is a complex, evolutionarily conserved process that plays a central role in host defense against infection. We have identified a predicted transmembrane protein, Eater, which is involved in phagocytosis in Drosophila. Transcriptional silencing of the eater gene in a macrophage cell line led to a significant reduction in the binding and internalization of bacteria. Moreover, the N terminus of the Eater protein mediated direct microbial binding which could be inhibited with scavenger receptor ligands, acetylated, and oxidized low-density lipoprotein. In vivo, eater expression was restricted to blood cells. Flies lacking the eater gene displayed normal responses in NF-kappaB-like Toll and IMD signaling pathways but showed impaired phagocytosis and decreased survival after bacterial infection. Our results suggest that Eater is a major phagocytic receptor for a broad range of bacterial pathogens in Drosophila and provide a powerful model to address the role of phagocytosis in vivo.},
keywords = {Amino Acid, Amino Acid Motifs, Animals, Bacterial Infections, Cell Surface, Embryo, Escherichia coli, ferrandon, Flow Cytometry, Frameshift Mutation, Genes, Histidine, hoffmann, In Situ Hybridization, Insect, Insect Proteins, M3i, Macrophages, Membrane Proteins, messenger, Nonmammalian, Open Reading Frames, Phagocytosis, Receptors, reichhart, RNA, RNA Interference, Sequence Homology, Serratia marcescens},
pubstate = {published},
tppubtype = {article}
}
Phagocytosis is a complex, evolutionarily conserved process that plays a central role in host defense against infection. We have identified a predicted transmembrane protein, Eater, which is involved in phagocytosis in Drosophila. Transcriptional silencing of the eater gene in a macrophage cell line led to a significant reduction in the binding and internalization of bacteria. Moreover, the N terminus of the Eater protein mediated direct microbial binding which could be inhibited with scavenger receptor ligands, acetylated, and oxidized low-density lipoprotein. In vivo, eater expression was restricted to blood cells. Flies lacking the eater gene displayed normal responses in NF-kappaB-like Toll and IMD signaling pathways but showed impaired phagocytosis and decreased survival after bacterial infection. Our results suggest that Eater is a major phagocytic receptor for a broad range of bacterial pathogens in Drosophila and provide a powerful model to address the role of phagocytosis in vivo.
Martinelli Cosimo, Reichhart Jean-Marc
Evolution and integration of innate immune systems from fruit flies to man: lessons and questions Article de journal
Dans: J. Endotoxin Res., vol. 11, no. 4, p. 243–248, 2005, ISSN: 0968-0519.
Résumé | Liens | BibTeX | Étiquettes: Animals, Biological Evolution, Cell Surface, Forecasting, Humans, Immunity, Immunological, Innate, M3i, Membrane Glycoproteins, Models, Receptors, reichhart, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors
@article{martinelli_evolution_2005,
title = {Evolution and integration of innate immune systems from fruit flies to man: lessons and questions},
author = {Cosimo Martinelli and Jean-Marc Reichhart},
doi = {10.1179/096805105X37411},
issn = {0968-0519},
year = {2005},
date = {2005-01-01},
journal = {J. Endotoxin Res.},
volume = {11},
number = {4},
pages = {243--248},
abstract = {Despite broad differences in morphology, ecology and behavior, the fruit fly Drosophila melanogaster and humans show a remarkably high degree of conservation for many molecular, cellular, and developmental aspects of their biology. During the last decade, similarities have also been discovered in some of the mechanisms regulating their innate immune system. These parallels regard mainly the Toll-like receptor family and the intracellular signaling pathways involved in the control of the immune response. However, if the overall similarities are important, the detailed pathogen recognition mechanisms differ significantly between fly and humans, highlighting a complicated evolutionary history of the metazoan innate defenses. In this review, we will discuss the main similarities and differences between the two types of organisms. We hope that this current knowledge will be used as a starting point for a more comprehensive view of innate immunity within the broad variety of metazoan phyla.},
keywords = {Animals, Biological Evolution, Cell Surface, Forecasting, Humans, Immunity, Immunological, Innate, M3i, Membrane Glycoproteins, Models, Receptors, reichhart, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Despite broad differences in morphology, ecology and behavior, the fruit fly Drosophila melanogaster and humans show a remarkably high degree of conservation for many molecular, cellular, and developmental aspects of their biology. During the last decade, similarities have also been discovered in some of the mechanisms regulating their innate immune system. These parallels regard mainly the Toll-like receptor family and the intracellular signaling pathways involved in the control of the immune response. However, if the overall similarities are important, the detailed pathogen recognition mechanisms differ significantly between fly and humans, highlighting a complicated evolutionary history of the metazoan innate defenses. In this review, we will discuss the main similarities and differences between the two types of organisms. We hope that this current knowledge will be used as a starting point for a more comprehensive view of innate immunity within the broad variety of metazoan phyla.
Weber Alexander N R, Moncrieffe Martin C, Gangloff Monique, Imler Jean-Luc, Gay Nicholas J
Ligand-receptor and receptor-receptor interactions act in concert to activate signaling in the Drosophila toll pathway Article de journal
Dans: The Journal of Biological Chemistry, vol. 280, no. 24, p. 22793–22799, 2005, ISSN: 0021-9258.
Résumé | Liens | BibTeX | Étiquettes: Amino Acid, Animals, Biophysical Phenomena, Biophysics, Body Patterning, Calorimetry, Cell Line, Cell Surface, Cross-Linking Reagents, Cytokines, dimerization, Electrophoresis, Humans, imler, ligands, Luciferases, M3i, Membrane Glycoproteins, Polyacrylamide Gel, Protein Binding, Protein Structure, Receptors, Recombinant Proteins, Sequence Homology, Signal Transduction, Tertiary, Time Factors, Toll-Like Receptors, Ultracentrifugation
@article{weber_ligand-receptor_2005,
title = {Ligand-receptor and receptor-receptor interactions act in concert to activate signaling in the Drosophila toll pathway},
author = {Alexander N R Weber and Martin C Moncrieffe and Monique Gangloff and Jean-Luc Imler and Nicholas J Gay},
doi = {10.1074/jbc.M502074200},
issn = {0021-9258},
year = {2005},
date = {2005-01-01},
journal = {The Journal of Biological Chemistry},
volume = {280},
number = {24},
pages = {22793--22799},
abstract = {In Drosophila, the signaling pathway mediated by the Toll receptor is critical for the establishment of embryonic dorso-ventral pattern and for innate immune responses to bacterial and fungal pathogens. Toll is activated by high affinity binding of the cytokine Spätzle, a dimeric ligand of the cystine knot family. In vertebrates, a related family of Toll-like receptors play a critical role in innate immune responses. Despite the importance of this family of receptors, little is known about the biochemical events that lead to receptor activation and signaling. Here, we show that Spätzle binds to the N-terminal region of Toll and, using biophysical methods, that the binding is complex. The two binding events that cause formation of the cross-linked complex are non-equivalent: the first Toll ectodomain binds Spätzle with an affinity 3-fold higher than the second molecule suggesting that pathway activation involves negative cooperativity. We further show that the Toll ectodomains are able to form low affinity dimers in solution and that juxtamembrane sequences of Toll are critical for the activation or derepression of the pathway. These results, taken together, suggest a mechanism of signal transduction that requires both ligand-receptor and receptor-receptor interactions.},
keywords = {Amino Acid, Animals, Biophysical Phenomena, Biophysics, Body Patterning, Calorimetry, Cell Line, Cell Surface, Cross-Linking Reagents, Cytokines, dimerization, Electrophoresis, Humans, imler, ligands, Luciferases, M3i, Membrane Glycoproteins, Polyacrylamide Gel, Protein Binding, Protein Structure, Receptors, Recombinant Proteins, Sequence Homology, Signal Transduction, Tertiary, Time Factors, Toll-Like Receptors, Ultracentrifugation},
pubstate = {published},
tppubtype = {article}
}
In Drosophila, the signaling pathway mediated by the Toll receptor is critical for the establishment of embryonic dorso-ventral pattern and for innate immune responses to bacterial and fungal pathogens. Toll is activated by high affinity binding of the cytokine Spätzle, a dimeric ligand of the cystine knot family. In vertebrates, a related family of Toll-like receptors play a critical role in innate immune responses. Despite the importance of this family of receptors, little is known about the biochemical events that lead to receptor activation and signaling. Here, we show that Spätzle binds to the N-terminal region of Toll and, using biophysical methods, that the binding is complex. The two binding events that cause formation of the cross-linked complex are non-equivalent: the first Toll ectodomain binds Spätzle with an affinity 3-fold higher than the second molecule suggesting that pathway activation involves negative cooperativity. We further show that the Toll ectodomains are able to form low affinity dimers in solution and that juxtamembrane sequences of Toll are critical for the activation or derepression of the pathway. These results, taken together, suggest a mechanism of signal transduction that requires both ligand-receptor and receptor-receptor interactions.
2004
Bischoff Vincent, Vignal Cécile, Boneca Ivo G, Michel Tatiana, Hoffmann Jules A, Royet Julien
Function of the drosophila pattern-recognition receptor PGRP-SD in the detection of Gram-positive bacteria Article de journal
Dans: Nat. Immunol., vol. 5, no. 11, p. 1175–1180, 2004, ISSN: 1529-2908.
Résumé | Liens | BibTeX | Étiquettes: Animals, Carrier Proteins, Cell Surface, Gram-Positive Bacteria, Gram-Positive Bacterial Infections, hoffmann, M3i, Mutation, Mycoses, Receptors, Staphylococcus aureus, Toll-Like Receptors
@article{bischoff_function_2004,
title = {Function of the drosophila pattern-recognition receptor PGRP-SD in the detection of Gram-positive bacteria},
author = {Vincent Bischoff and Cécile Vignal and Ivo G Boneca and Tatiana Michel and Jules A Hoffmann and Julien Royet},
doi = {10.1038/ni1123},
issn = {1529-2908},
year = {2004},
date = {2004-11-01},
journal = {Nat. Immunol.},
volume = {5},
number = {11},
pages = {1175--1180},
abstract = {The activation of an immune response requires recognition of microorganisms by host receptors. In drosophila, detection of Gram-positive bacteria is mediated by cooperation between the peptidoglycan-recognition protein-SA (PGRP-SA) and Gram-negative binding protein 1 (GNBP1) proteins. Here we show that some Gram-positive bacterial species activate an immune response in a PGRP-SA- and GNBP1-independent manner, indicating that alternative receptors exist. Consistent with this, we noted that PGRP-SD mutants were susceptible to some Gram-positive bacteria and that a loss-of-function mutation in PGRP-SD severely exacerbated the PGRP-SA and GNBP1 mutant phenotypes. These data indicate that PGRP-SD can function as a receptor for Gram-positive bacteria and shows partial redundancy with the PGRP-SA-GNBP1 complex.},
keywords = {Animals, Carrier Proteins, Cell Surface, Gram-Positive Bacteria, Gram-Positive Bacterial Infections, hoffmann, M3i, Mutation, Mycoses, Receptors, Staphylococcus aureus, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The activation of an immune response requires recognition of microorganisms by host receptors. In drosophila, detection of Gram-positive bacteria is mediated by cooperation between the peptidoglycan-recognition protein-SA (PGRP-SA) and Gram-negative binding protein 1 (GNBP1) proteins. Here we show that some Gram-positive bacterial species activate an immune response in a PGRP-SA- and GNBP1-independent manner, indicating that alternative receptors exist. Consistent with this, we noted that PGRP-SD mutants were susceptible to some Gram-positive bacteria and that a loss-of-function mutation in PGRP-SD severely exacerbated the PGRP-SA and GNBP1 mutant phenotypes. These data indicate that PGRP-SD can function as a receptor for Gram-positive bacteria and shows partial redundancy with the PGRP-SA-GNBP1 complex.
Leclerc Vincent, Reichhart Jean-Marc
The immune response of Drosophila melanogaster Article de journal
Dans: Immunol. Rev., vol. 198, p. 59–71, 2004, ISSN: 0105-2896.
Résumé | BibTeX | Étiquettes: Animals, Cell Surface, Immunity, Immunological, Innate, M3i, Models, Receptors, reichhart, Signal Transduction, Toll-Like Receptors
@article{leclerc_immune_2004,
title = {The immune response of Drosophila melanogaster},
author = {Vincent Leclerc and Jean-Marc Reichhart},
issn = {0105-2896},
year = {2004},
date = {2004-04-01},
journal = {Immunol. Rev.},
volume = {198},
pages = {59--71},
abstract = {The response of the fruit fly Drosophila melanogaster to various microorganism infections relies on a multilayered defense. The epithelia constitute a first and efficient barrier. Innate immunity is activated when microorganisms succeed in entering the body cavity of the fly. Invading microorganisms are killed by the combined action of cellular and humoral processes. They are phagocytosed by specialized blood cells, surrounded by toxic melanin, or lysed by antibacterial peptides secreted into the hemolymph by fat body cells. During the last few years, research has focused on the mechanisms of microbial recognition by various pattern recognition receptors and of the subsequent induction of antimicrobial peptide expression. The cellular arm of the Drosophila innate immune system, which was somehow neglected, now constitutes the new frontier.},
keywords = {Animals, Cell Surface, Immunity, Immunological, Innate, M3i, Models, Receptors, reichhart, Signal Transduction, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The response of the fruit fly Drosophila melanogaster to various microorganism infections relies on a multilayered defense. The epithelia constitute a first and efficient barrier. Innate immunity is activated when microorganisms succeed in entering the body cavity of the fly. Invading microorganisms are killed by the combined action of cellular and humoral processes. They are phagocytosed by specialized blood cells, surrounded by toxic melanin, or lysed by antibacterial peptides secreted into the hemolymph by fat body cells. During the last few years, research has focused on the mechanisms of microbial recognition by various pattern recognition receptors and of the subsequent induction of antimicrobial peptide expression. The cellular arm of the Drosophila innate immune system, which was somehow neglected, now constitutes the new frontier.
Imler Jean-Luc, Zheng Liangbiao
Biology of Toll receptors: lessons from insects and mammals Article de journal
Dans: Journal of Leukocyte Biology, vol. 75, no. 1, p. 18–26, 2004, ISSN: 0741-5400.
Résumé | Liens | BibTeX | Étiquettes: Animals, Anopheles, Cell Surface, Humans, imler, M3i, Membrane Glycoproteins, Mice, Phylogeny, Plant Physiological Phenomena, Receptors, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors
@article{imler_biology_2004,
title = {Biology of Toll receptors: lessons from insects and mammals},
author = {Jean-Luc Imler and Liangbiao Zheng},
doi = {10.1189/jlb.0403160},
issn = {0741-5400},
year = {2004},
date = {2004-01-01},
journal = {Journal of Leukocyte Biology},
volume = {75},
number = {1},
pages = {18--26},
abstract = {Toll receptors are type I transmembrane proteins that play important roles in development and immunity in animals. Comparison of the genomes of mouse and human on one side and of the fruitfly Drosophila and the mosquito Anopheles (two dipteran insects) on the other, revealed that the four species possess a similar number of Toll receptors (approximately 10). However, phylogenetic analyses indicate that the families of Toll receptors expanded independently in insects and mammals. We review recent results on these receptors, which point to differences in the activation and signaling between Tolls in insects and Toll-like receptors (TLRs) in mammals. Whereas mammalian TLRs appear to be solely dedicated to host-defense, insect Tolls may be predominantly linked to other functions, probably developmental.},
keywords = {Animals, Anopheles, Cell Surface, Humans, imler, M3i, Membrane Glycoproteins, Mice, Phylogeny, Plant Physiological Phenomena, Receptors, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Toll receptors are type I transmembrane proteins that play important roles in development and immunity in animals. Comparison of the genomes of mouse and human on one side and of the fruitfly Drosophila and the mosquito Anopheles (two dipteran insects) on the other, revealed that the four species possess a similar number of Toll receptors (approximately 10). However, phylogenetic analyses indicate that the families of Toll receptors expanded independently in insects and mammals. We review recent results on these receptors, which point to differences in the activation and signaling between Tolls in insects and Toll-like receptors (TLRs) in mammals. Whereas mammalian TLRs appear to be solely dedicated to host-defense, insect Tolls may be predominantly linked to other functions, probably developmental.
Imler Jean-Luc, Ferrandon Dominique, Royet Julien, Reichhart Jean-Marc, Hetru Charles, Hoffmann Jules A
Toll-dependent and Toll-independent immune responses in Drosophila Article de journal
Dans: Journal of Endotoxin Research, vol. 10, no. 4, p. 241–246, 2004, ISSN: 0968-0519.
Résumé | Liens | BibTeX | Étiquettes: Acute-Phase Proteins, Animals, Blood Proteins, Cell Surface, ferrandon, hoffmann, imler, Insect Proteins, M3i, Membrane Glycoproteins, Receptors, reichhart, Toll-Like Receptor 5, Toll-Like Receptors, Up-Regulation
@article{imler_toll-dependent_2004,
title = {Toll-dependent and Toll-independent immune responses in Drosophila},
author = {Jean-Luc Imler and Dominique Ferrandon and Julien Royet and Jean-Marc Reichhart and Charles Hetru and Jules A Hoffmann},
doi = {10.1179/096805104225005887},
issn = {0968-0519},
year = {2004},
date = {2004-01-01},
journal = {Journal of Endotoxin Research},
volume = {10},
number = {4},
pages = {241--246},
abstract = {The multifaceted response of the fruitfly Drosophila melanogaster to infection by a wide range of microbes is complex and remarkably efficient. Its most prominent aspect is the immune-inducible expression of a set of potent antimicrobial peptides. Genetic analysis of the regulation of the genes encoding these peptides has led to the identification of the receptor Toll as an essential component of the fly's host defense system. In addition, these studies have revealed that the response to Gram-negative bacterial infections involves Toll-independent mechanisms, and that the sensing of infection involves two structurally distinct sets of molecules--the PGRPs and the GNBPs/betaGRPs.},
keywords = {Acute-Phase Proteins, Animals, Blood Proteins, Cell Surface, ferrandon, hoffmann, imler, Insect Proteins, M3i, Membrane Glycoproteins, Receptors, reichhart, Toll-Like Receptor 5, Toll-Like Receptors, Up-Regulation},
pubstate = {published},
tppubtype = {article}
}
The multifaceted response of the fruitfly Drosophila melanogaster to infection by a wide range of microbes is complex and remarkably efficient. Its most prominent aspect is the immune-inducible expression of a set of potent antimicrobial peptides. Genetic analysis of the regulation of the genes encoding these peptides has led to the identification of the receptor Toll as an essential component of the fly's host defense system. In addition, these studies have revealed that the response to Gram-negative bacterial infections involves Toll-independent mechanisms, and that the sensing of infection involves two structurally distinct sets of molecules--the PGRPs and the GNBPs/betaGRPs.
2003
Ligoxygakis Petros, Roth Siegfried, Reichhart Jean-Marc
A serpin regulates dorsal-ventral axis formation in the Drosophila embryo Article de journal
Dans: Curr. Biol., vol. 13, no. 23, p. 2097–2102, 2003, ISSN: 0960-9822.
Résumé | BibTeX | Étiquettes: Animals, Body Patterning, Cell Surface, Crosses, Female, Genetic, Immunohistochemistry, M3i, Microinjections, Receptors, reichhart, Serine Proteinase Inhibitors, Serpins, Signal Transduction, Toll-Like Receptors
@article{ligoxygakis_serpin_2003,
title = {A serpin regulates dorsal-ventral axis formation in the Drosophila embryo},
author = {Petros Ligoxygakis and Siegfried Roth and Jean-Marc Reichhart},
issn = {0960-9822},
year = {2003},
date = {2003-12-01},
journal = {Curr. Biol.},
volume = {13},
number = {23},
pages = {2097--2102},
abstract = {Extracellular serine protease cascades have evolved in vertebrates and invertebrates to mediate rapid, local reactions to physiological or pathological cues. The serine protease cascade that triggers the Toll signaling pathway in Drosophila embryogenesis shares several organizational characteristics with those involved in mammalian complement and blood clotting. One of the hallmarks of such cascades is their regulation by serine protease inhibitors (serpins). Serpins act as suicide substrates and are cleaved by their target protease, forming an essentially irreversible 1:1 complex. The biological importance of serpins is highlighted by serpin dysfunction diseases, such as thrombosis caused by a deficiency in antithrombin. Here, we describe how a serpin controls the serine protease cascade, leading to Toll pathway activation. Female flies deficient in Serpin-27A produce embryos that lack dorsal-ventral polarity and show uniform high levels of Toll signaling. Since this serpin has been recently shown to restrain an immune reaction in the blood of Drosophila, it demonstrates that proteolysis can be regulated by the same serpin in different biological contexts.},
keywords = {Animals, Body Patterning, Cell Surface, Crosses, Female, Genetic, Immunohistochemistry, M3i, Microinjections, Receptors, reichhart, Serine Proteinase Inhibitors, Serpins, Signal Transduction, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Extracellular serine protease cascades have evolved in vertebrates and invertebrates to mediate rapid, local reactions to physiological or pathological cues. The serine protease cascade that triggers the Toll signaling pathway in Drosophila embryogenesis shares several organizational characteristics with those involved in mammalian complement and blood clotting. One of the hallmarks of such cascades is their regulation by serine protease inhibitors (serpins). Serpins act as suicide substrates and are cleaved by their target protease, forming an essentially irreversible 1:1 complex. The biological importance of serpins is highlighted by serpin dysfunction diseases, such as thrombosis caused by a deficiency in antithrombin. Here, we describe how a serpin controls the serine protease cascade, leading to Toll pathway activation. Female flies deficient in Serpin-27A produce embryos that lack dorsal-ventral polarity and show uniform high levels of Toll signaling. Since this serpin has been recently shown to restrain an immune reaction in the blood of Drosophila, it demonstrates that proteolysis can be regulated by the same serpin in different biological contexts.
Reichhart Jean-Marc
TLR5 takes aim at bacterial propeller Article de journal
Dans: Nat. Immunol., vol. 4, no. 12, p. 1159–1160, 2003, ISSN: 1529-2908.
Liens | BibTeX | Étiquettes: Animals, Bacterial Physiological Phenomena, Cell Surface, Flagella, Flagellin, Humans, M3i, Membrane Glycoproteins, Receptors, reichhart, Toll-Like Receptor 5, Toll-Like Receptors
@article{reichhart_tlr5_2003,
title = {TLR5 takes aim at bacterial propeller},
author = {Jean-Marc Reichhart},
doi = {10.1038/ni1203-1159},
issn = {1529-2908},
year = {2003},
date = {2003-12-01},
journal = {Nat. Immunol.},
volume = {4},
number = {12},
pages = {1159--1160},
keywords = {Animals, Bacterial Physiological Phenomena, Cell Surface, Flagella, Flagellin, Humans, M3i, Membrane Glycoproteins, Receptors, reichhart, Toll-Like Receptor 5, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Gobert Vanessa, Gottar Marie, Matskevich Alexey A, Rutschmann Sophie, Royet Julien, Belvin Marcia, Hoffmann Jules A, Ferrandon Dominique
Dual activation of the Drosophila toll pathway by two pattern recognition receptors Article de journal
Dans: Science, vol. 302, no. 5653, p. 2126–2130, 2003, ISSN: 1095-9203.
Résumé | Liens | BibTeX | Étiquettes: Animals, Carrier Proteins, Cell Surface, DNA Transposable Elements, ferrandon, Gene Expression, Genes, Gram-Negative Bacteria, Gram-Positive Bacteria, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Mutation, Phenotype, Receptors, Serine Endopeptidases, Toll-Like Receptors
@article{gobert_dual_2003,
title = {Dual activation of the Drosophila toll pathway by two pattern recognition receptors},
author = {Vanessa Gobert and Marie Gottar and Alexey A Matskevich and Sophie Rutschmann and Julien Royet and Marcia Belvin and Jules A Hoffmann and Dominique Ferrandon},
doi = {10.1126/science.1085432},
issn = {1095-9203},
year = {2003},
date = {2003-12-01},
journal = {Science},
volume = {302},
number = {5653},
pages = {2126--2130},
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.},
keywords = {Animals, Carrier Proteins, Cell Surface, DNA Transposable Elements, ferrandon, Gene Expression, Genes, Gram-Negative Bacteria, Gram-Positive Bacteria, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Mutation, Phenotype, Receptors, Serine Endopeptidases, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
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.
Goto Akira, Blandin Stéphanie A, Royet Julien, Reichhart Jean-Marc, Levashina Elena A
Silencing of Toll pathway components by direct injection of double-stranded RNA into Drosophila adult flies Article de journal
Dans: Nucleic Acids Res., vol. 31, no. 22, p. 6619–6623, 2003, ISSN: 1362-4962.
Résumé | BibTeX | Étiquettes: Animals, blandin, Cell Surface, Double-Stranded, Epistasis, Female, Genetic, Green Fluorescent Proteins, Homeodomain Proteins, Luminescent Proteins, M3i, Phenotype, Receptors, reichhart, RNA, RNA Interference, Serpins, Signal Transduction, Time Factors, Toll-Like Receptors, Transcription Factors
@article{goto_silencing_2003,
title = {Silencing of Toll pathway components by direct injection of double-stranded RNA into Drosophila adult flies},
author = {Akira Goto and Stéphanie A Blandin and Julien Royet and Jean-Marc Reichhart and Elena A Levashina},
issn = {1362-4962},
year = {2003},
date = {2003-11-01},
journal = {Nucleic Acids Res.},
volume = {31},
number = {22},
pages = {6619--6623},
abstract = {Double-stranded RNA (dsRNA) gene interference is an efficient method to silence gene expression in a sequence-specific manner. Here we show that the direct injection of dsRNA can be used in adult Drosophila flies to disrupt function of endogenous genes in vivo. As a proof of principle, we have used this method to silence components of a major signaling cascade, the Toll pathway, which controls fruit fly resistance to fungal and Gram-positive bacterial infections. We demonstrate that the knockout is efficient only if dsRNA is injected in 4- or more day-old flies and that it lasts for at least 1 week. Furthermore, we report dsRNA-based epistatic gene analysis via injection of a mixture of two dsRNAs and propose that injection of dsRNA represents a powerful method for rapid functional analysis of genes in Drosophila melanogaster adults, particularly of those whose mutations are lethal during development.},
keywords = {Animals, blandin, Cell Surface, Double-Stranded, Epistasis, Female, Genetic, Green Fluorescent Proteins, Homeodomain Proteins, Luminescent Proteins, M3i, Phenotype, Receptors, reichhart, RNA, RNA Interference, Serpins, Signal Transduction, Time Factors, Toll-Like Receptors, Transcription Factors},
pubstate = {published},
tppubtype = {article}
}
Double-stranded RNA (dsRNA) gene interference is an efficient method to silence gene expression in a sequence-specific manner. Here we show that the direct injection of dsRNA can be used in adult Drosophila flies to disrupt function of endogenous genes in vivo. As a proof of principle, we have used this method to silence components of a major signaling cascade, the Toll pathway, which controls fruit fly resistance to fungal and Gram-positive bacterial infections. We demonstrate that the knockout is efficient only if dsRNA is injected in 4- or more day-old flies and that it lasts for at least 1 week. Furthermore, we report dsRNA-based epistatic gene analysis via injection of a mixture of two dsRNAs and propose that injection of dsRNA represents a powerful method for rapid functional analysis of genes in Drosophila melanogaster adults, particularly of those whose mutations are lethal during development.
Hoffmann Jules A
The immune response of Drosophila Article de journal
Dans: Nature, vol. 426, no. 6962, p. 33–38, 2003, ISSN: 1476-4687.
Résumé | Liens | BibTeX | Étiquettes: Animals, Cell Surface, hoffmann, Immunity, Innate, M3i, Membrane Glycoproteins, Receptors, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors
@article{hoffmann_immune_2003,
title = {The immune response of Drosophila},
author = {Jules A Hoffmann},
doi = {10.1038/nature02021},
issn = {1476-4687},
year = {2003},
date = {2003-11-01},
journal = {Nature},
volume = {426},
number = {6962},
pages = {33--38},
abstract = {Drosophila mounts a potent host defence when challenged by various microorganisms. Analysis of this defence by molecular genetics has now provided a global picture of the mechanisms by which this insect senses infection, discriminates between various classes of microorganisms and induces the production of effector molecules, among which antimicrobial peptides are prominent. An unexpected result of these studies was the discovery that most of the genes involved in the Drosophila host defence are homologous or very similar to genes implicated in mammalian innate immune defences. Recent progress in research on Drosophila immune defence provides evidence for similarities and differences between Drosophila immune responses and mammalian innate immunity.},
keywords = {Animals, Cell Surface, hoffmann, Immunity, Innate, M3i, Membrane Glycoproteins, Receptors, Signal Transduction, Toll-Like Receptor 5, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Drosophila mounts a potent host defence when challenged by various microorganisms. Analysis of this defence by molecular genetics has now provided a global picture of the mechanisms by which this insect senses infection, discriminates between various classes of microorganisms and induces the production of effector molecules, among which antimicrobial peptides are prominent. An unexpected result of these studies was the discovery that most of the genes involved in the Drosophila host defence are homologous or very similar to genes implicated in mammalian innate immune defences. Recent progress in research on Drosophila immune defence provides evidence for similarities and differences between Drosophila immune responses and mammalian innate immunity.
Weber Alexander N R, Tauszig-Delamasure Servane, Hoffmann Jules A, Lelièvre Eric, Gascan Hugues, Ray Keith P, Morse Mary A, Imler Jean-Luc, Gay Nicholas J
Binding of the Drosophila cytokine Spätzle to Toll is direct and establishes signaling Article de journal
Dans: Nature Immunology, vol. 4, no. 8, p. 794–800, 2003, ISSN: 1529-2908.
Résumé | Liens | BibTeX | Étiquettes: Animals, Cell Surface, hoffmann, imler, Insect Proteins, M3i, Protein Binding, Protein Structure, Receptors, Signal Transduction, Tertiary, Toll-Like Receptors
@article{weber_binding_2003,
title = {Binding of the Drosophila cytokine Spätzle to Toll is direct and establishes signaling},
author = {Alexander N R Weber and Servane Tauszig-Delamasure and Jules A Hoffmann and Eric Lelièvre and Hugues Gascan and Keith P Ray and Mary A Morse and Jean-Luc Imler and Nicholas J Gay},
doi = {10.1038/ni955},
issn = {1529-2908},
year = {2003},
date = {2003-08-01},
journal = {Nature Immunology},
volume = {4},
number = {8},
pages = {794--800},
abstract = {The extracellular protein Spätzle is required for activation of the Toll signaling pathway in the embryonic development and innate immune defense of Drosophila. Spätzle is synthesized as a pro-protein and is processed to a functional form by a serine protease. We show here that the mature form of Spätzle triggers a Toll-dependent immune response after injection into the hemolymph of flies. Spätzle specifically bound to Drosophila cells and to Cos-7 cells expressing Toll. Furthermore, in vitro experiments showed that the mature form of Spätzle bound to the Toll ectodomain with high affinity and with a stoichiometry of one Spätzle dimer to two receptors. The Spätzle pro-protein was inactive in all these assays, indicating that the pro-domain sequence, which is natively unstructured, acts to prevent interaction of the cytokine and its receptor Toll. These results show that, in contrast to the human Toll-like receptors, Drosophila Toll requires only an endogenous protein ligand for activation and signaling.},
keywords = {Animals, Cell Surface, hoffmann, imler, Insect Proteins, M3i, Protein Binding, Protein Structure, Receptors, Signal Transduction, Tertiary, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The extracellular protein Spätzle is required for activation of the Toll signaling pathway in the embryonic development and innate immune defense of Drosophila. Spätzle is synthesized as a pro-protein and is processed to a functional form by a serine protease. We show here that the mature form of Spätzle triggers a Toll-dependent immune response after injection into the hemolymph of flies. Spätzle specifically bound to Drosophila cells and to Cos-7 cells expressing Toll. Furthermore, in vitro experiments showed that the mature form of Spätzle bound to the Toll ectodomain with high affinity and with a stoichiometry of one Spätzle dimer to two receptors. The Spätzle pro-protein was inactive in all these assays, indicating that the pro-domain sequence, which is natively unstructured, acts to prevent interaction of the cytokine and its receptor Toll. These results show that, in contrast to the human Toll-like receptors, Drosophila Toll requires only an endogenous protein ligand for activation and signaling.
Bilak Hana, Tauszig-Delamasure S, Imler Jean-Luc
Toll and Toll-like receptors in Drosophila Article de journal
Dans: Biochemical Society Transactions, vol. 31, no. Pt 3, p. 648–651, 2003, ISSN: 0300-5127.
Résumé | Liens | BibTeX | Étiquettes: Animals, Biological Evolution, Cell Surface, Fungi, Genome, Gram-Negative Bacteria, Gram-Positive Bacteria, imler, M3i, Membrane Glycoproteins, Receptors, Toll-Like Receptor 5, Toll-Like Receptors
@article{bilak_toll_2003,
title = {Toll and Toll-like receptors in Drosophila},
author = {Hana Bilak and S Tauszig-Delamasure and Jean-Luc Imler},
doi = {10.1042/},
issn = {0300-5127},
year = {2003},
date = {2003-06-01},
journal = {Biochemical Society Transactions},
volume = {31},
number = {Pt 3},
pages = {648--651},
abstract = {The Drosophila Toll receptor controls the immune response to Gram-positive bacteria and fungi by activating a signalling pathway partially conserved throughout evolution. The Drosophila genome encodes eight additional Toll-related receptors, most of which appear to carry out developmental rather than immune functions. One exception may be Toll-9, which shares structural and functional similarities with mammalian TLRs.},
keywords = {Animals, Biological Evolution, Cell Surface, Fungi, Genome, Gram-Negative Bacteria, Gram-Positive Bacteria, imler, M3i, Membrane Glycoproteins, Receptors, Toll-Like Receptor 5, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The Drosophila Toll receptor controls the immune response to Gram-positive bacteria and fungi by activating a signalling pathway partially conserved throughout evolution. The Drosophila genome encodes eight additional Toll-related receptors, most of which appear to carry out developmental rather than immune functions. One exception may be Toll-9, which shares structural and functional similarities with mammalian TLRs.
Luna C, Hoa N T, Zhang J, Kanzok S M, Brown S E, Imler Jean-Luc, Knudson D L, Zheng L
Characterization of three Toll-like genes from mosquito Aedes aegypti Article de journal
Dans: Insect Molecular Biology, vol. 12, no. 1, p. 67–74, 2003, ISSN: 0962-1075.
Résumé | BibTeX | Étiquettes: Aedes, Animals, Base Sequence, Cell Surface, Chimera, Cloning, Developmental, Female, Gene Expression Regulation, Genetic, imler, Insect Proteins, M3i, Male, messenger, Models, Molecular, Mutagenesis, Promoter Regions, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA, Sequence Alignment, Signal Transduction, Site-Directed, Transfection
@article{luna_characterization_2003,
title = {Characterization of three Toll-like genes from mosquito Aedes aegypti},
author = {C Luna and N T Hoa and J Zhang and S M Kanzok and S E Brown and Jean-Luc Imler and D L Knudson and L Zheng},
issn = {0962-1075},
year = {2003},
date = {2003-02-01},
journal = {Insect Molecular Biology},
volume = {12},
number = {1},
pages = {67--74},
abstract = {Three Toll-related genes (AeToll1A, AeToll1B and AeToll5) were cloned and characterized from the yellow fever vector mosquito, Aedes aegypti. All three genes exhibited high levels of amino acid sequence similarity with Drosophila melanogaster (Dm)Toll1 and DmTehao (Toll5). AeToll1A and AeToll1B are 1124 and 1076 amino acid residues long, respectively. Both contain a carboxyl extension downstream of the Toll/interleukin-1 receptor (TIR) domain. AeToll5 is 1007 residues long and, like DmTehao, lacks the carboxyl terminal extension. Expression of these three genes was examined throughout development and after immune challenge. Both AeToll1A and AeToll5, like their Drosophila counterparts, activate transcription of drosomycin promoter in both Aedes and Drosophila cell lines. Deletion of the carboxyl extension of AeToll1A did not result in a further elevated level of the antifungal response. The intracellular signalling process appears to be species specific based on two observations. (1) DmToll is completely inactive in an Aedes cell line, suggesting a higher specificity requirement for DmToll in the intracellular signalling process. (2) Only one of three amino acid residues essential for DmToll function is required for AeToll1A function.},
keywords = {Aedes, Animals, Base Sequence, Cell Surface, Chimera, Cloning, Developmental, Female, Gene Expression Regulation, Genetic, imler, Insect Proteins, M3i, Male, messenger, Models, Molecular, Mutagenesis, Promoter Regions, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA, Sequence Alignment, Signal Transduction, Site-Directed, Transfection},
pubstate = {published},
tppubtype = {article}
}
Three Toll-related genes (AeToll1A, AeToll1B and AeToll5) were cloned and characterized from the yellow fever vector mosquito, Aedes aegypti. All three genes exhibited high levels of amino acid sequence similarity with Drosophila melanogaster (Dm)Toll1 and DmTehao (Toll5). AeToll1A and AeToll1B are 1124 and 1076 amino acid residues long, respectively. Both contain a carboxyl extension downstream of the Toll/interleukin-1 receptor (TIR) domain. AeToll5 is 1007 residues long and, like DmTehao, lacks the carboxyl terminal extension. Expression of these three genes was examined throughout development and after immune challenge. Both AeToll1A and AeToll5, like their Drosophila counterparts, activate transcription of drosomycin promoter in both Aedes and Drosophila cell lines. Deletion of the carboxyl extension of AeToll1A did not result in a further elevated level of the antifungal response. The intracellular signalling process appears to be species specific based on two observations. (1) DmToll is completely inactive in an Aedes cell line, suggesting a higher specificity requirement for DmToll in the intracellular signalling process. (2) Only one of three amino acid residues essential for DmToll function is required for AeToll1A function.
Imler Jean-Luc, Hoffmann Jules A
Toll signaling: the TIReless quest for specificity Article de journal
Dans: Nature Immunology, vol. 4, no. 2, p. 105–106, 2003, ISSN: 1529-2908.
Liens | BibTeX | Étiquettes: Animals, Cell Surface, Dendritic Cells, hoffmann, Humans, imler, Immunological, Interferon-beta, M3i, Membrane Glycoproteins, Mice, Models, Protein Structure, Receptors, Signal Transduction, Tertiary, Toll-Like Receptors
@article{imler_toll_2003,
title = {Toll signaling: the TIReless quest for specificity},
author = {Jean-Luc Imler and Jules A Hoffmann},
doi = {10.1038/ni0203-105},
issn = {1529-2908},
year = {2003},
date = {2003-02-01},
journal = {Nature Immunology},
volume = {4},
number = {2},
pages = {105--106},
keywords = {Animals, Cell Surface, Dendritic Cells, hoffmann, Humans, imler, Immunological, Interferon-beta, M3i, Membrane Glycoproteins, Mice, Models, Protein Structure, Receptors, Signal Transduction, Tertiary, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Kambris Zakaria, Bilak Hana, D'Alessandro Rosalba, Belvin Marcia, Imler Jean-Luc, Capovilla Maria
DmMyD88 controls dorsoventral patterning of the Drosophila embryo Article de journal
Dans: EMBO reports, vol. 4, no. 1, p. 64–69, 2003, ISSN: 1469-221X.
Résumé | Liens | BibTeX | Étiquettes: Adaptor Proteins, Alleles, Animals, Antigens, Base Sequence, Cell Surface, Complementary, Developmental, Differentiation, DNA, DNA Transposable Elements, Egg Proteins, Embryo, Exons, Female, Gene Expression Regulation, Genetically Modified, Genotype, imler, Immunity, Immunologic, Innate, Insertional, M3i, Male, messenger, Morphogenesis, Mutagenesis, Myeloid Differentiation Factor 88, Nonmammalian, Oocytes, Protein Biosynthesis, Protein Structure, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA, Signal Transducing, Tertiary, Toll-Like Receptors, Zygote
@article{kambris_dmmyd88_2003,
title = {DmMyD88 controls dorsoventral patterning of the Drosophila embryo},
author = {Zakaria Kambris and Hana Bilak and Rosalba D'Alessandro and Marcia Belvin and Jean-Luc Imler and Maria Capovilla},
doi = {10.1038/sj.embor.embor714},
issn = {1469-221X},
year = {2003},
date = {2003-01-01},
journal = {EMBO reports},
volume = {4},
number = {1},
pages = {64--69},
abstract = {MyD88 is an adapter protein in the signal transduction pathway mediated by interleukin-1 (IL-1) and Toll-like receptors. A Drosophila homologue of MyD88 (DmMyD88) was recently shown to be required for the Toll-mediated immune response. In Drosophila, the Toll pathway was originally characterized for its role in the dorsoventral patterning of the embryo. We found that, like Toll, DmMyD88 messenger RNA is maternally supplied to the embryo. Here we report the identification of a new mutant allele of DmMyD88, which generates a protein lacking the carboxy-terminal extension, normally located downstream of the Toll/IL-1 receptor domain. Homozygous mutant female flies lay dorsalized embryos that are rescued by expression of a transgenic DmMyD88 complementary DNA. The DmMyD88 mutation blocks the ventralizing activity of a gain-of-function Toll mutation. These results show that DmMyD88 encodes an essential component of the Toll pathway in dorsoventral pattern formation.},
keywords = {Adaptor Proteins, Alleles, Animals, Antigens, Base Sequence, Cell Surface, Complementary, Developmental, Differentiation, DNA, DNA Transposable Elements, Egg Proteins, Embryo, Exons, Female, Gene Expression Regulation, Genetically Modified, Genotype, imler, Immunity, Immunologic, Innate, Insertional, M3i, Male, messenger, Morphogenesis, Mutagenesis, Myeloid Differentiation Factor 88, Nonmammalian, Oocytes, Protein Biosynthesis, Protein Structure, Receptors, Reverse Transcriptase Polymerase Chain Reaction, RNA, Signal Transducing, Tertiary, Toll-Like Receptors, Zygote},
pubstate = {published},
tppubtype = {article}
}
MyD88 is an adapter protein in the signal transduction pathway mediated by interleukin-1 (IL-1) and Toll-like receptors. A Drosophila homologue of MyD88 (DmMyD88) was recently shown to be required for the Toll-mediated immune response. In Drosophila, the Toll pathway was originally characterized for its role in the dorsoventral patterning of the embryo. We found that, like Toll, DmMyD88 messenger RNA is maternally supplied to the embryo. Here we report the identification of a new mutant allele of DmMyD88, which generates a protein lacking the carboxy-terminal extension, normally located downstream of the Toll/IL-1 receptor domain. Homozygous mutant female flies lay dorsalized embryos that are rescued by expression of a transgenic DmMyD88 complementary DNA. The DmMyD88 mutation blocks the ventralizing activity of a gain-of-function Toll mutation. These results show that DmMyD88 encodes an essential component of the Toll pathway in dorsoventral pattern formation.
2002
Ligoxygakis Petros, Pelte Nadège, Ji Chuanyi, Leclerc Vincent, Duvic Bernard, Belvin Marcia, Jiang Haobo, Hoffmann Jules A, Reichhart Jean-Marc
A serpin mutant links Toll activation to melanization in the host defence of Drosophila Article de journal
Dans: EMBO J., vol. 21, no. 23, p. 6330–6337, 2002, ISSN: 0261-4189.
Résumé | BibTeX | Étiquettes: Animals, Cell Surface, Hemolymph, hoffmann, infection, M3i, Melanins, Receptors, reichhart, Serpins, Toll-Like Receptors
@article{ligoxygakis_serpin_2002,
title = {A serpin mutant links Toll activation to melanization in the host defence of Drosophila},
author = {Petros Ligoxygakis and Nadège Pelte and Chuanyi Ji and Vincent Leclerc and Bernard Duvic and Marcia Belvin and Haobo Jiang and Jules A Hoffmann and Jean-Marc Reichhart},
issn = {0261-4189},
year = {2002},
date = {2002-12-01},
journal = {EMBO J.},
volume = {21},
number = {23},
pages = {6330--6337},
abstract = {A prominent response during the Drosophila host defence is the induction of proteolytic cascades, some of which lead to localized melanization of pathogen surfaces, while others activate one of the major players in the systemic antimicrobial response, the Toll pathway. Despite the fact that gain-of-function mutations in the Toll receptor gene result in melanization, a clear link between Toll activation and the melanization reaction has not been firmly established. Here, we present evidence for the coordination of hemolymph-borne melanization with activation of the Toll pathway in the Drosophila host defence. The melanization reaction requires Toll pathway activation and depends on the removal of the Drosophila serine protease inhibitor Serpin27A. Flies deficient for this serpin exhibit spontaneous melanization in larvae and adults. Microbial challenge induces its removal from the hemolymph through Toll-dependent transcription of an acute phase immune reaction component.},
keywords = {Animals, Cell Surface, Hemolymph, hoffmann, infection, M3i, Melanins, Receptors, reichhart, Serpins, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
A prominent response during the Drosophila host defence is the induction of proteolytic cascades, some of which lead to localized melanization of pathogen surfaces, while others activate one of the major players in the systemic antimicrobial response, the Toll pathway. Despite the fact that gain-of-function mutations in the Toll receptor gene result in melanization, a clear link between Toll activation and the melanization reaction has not been firmly established. Here, we present evidence for the coordination of hemolymph-borne melanization with activation of the Toll pathway in the Drosophila host defence. The melanization reaction requires Toll pathway activation and depends on the removal of the Drosophila serine protease inhibitor Serpin27A. Flies deficient for this serpin exhibit spontaneous melanization in larvae and adults. Microbial challenge induces its removal from the hemolymph through Toll-dependent transcription of an acute phase immune reaction component.
Kambris Zakaria, Hoffmann Jules A, Imler Jean-Luc, Capovilla Maria
Tissue and stage-specific expression of the Tolls in Drosophila embryos Article de journal
Dans: Gene expression patterns: GEP, vol. 2, no. 3-4, p. 311–317, 2002, ISSN: 1567-133X.
Résumé | BibTeX | Étiquettes: Animals, Blotting, Cell Surface, Gene Expression Profiling, hoffmann, imler, Larva, M3i, Multigene Family, Northern, Receptors, Toll-Like Receptors
@article{kambris_tissue_2002,
title = {Tissue and stage-specific expression of the Tolls in Drosophila embryos},
author = {Zakaria Kambris and Jules A Hoffmann and Jean-Luc Imler and Maria Capovilla},
issn = {1567-133X},
year = {2002},
date = {2002-12-01},
journal = {Gene expression patterns: GEP},
volume = {2},
number = {3-4},
pages = {311--317},
abstract = {The Drosophila transmembrane receptor Toll plays a key role in specifying the dorsoventral axis of the embryo. At later stages of development, it controls the immune response of the fly to fungal and Gram-positive bacterial infections. The Drosophila genome has a total of nine Toll-like genes, including the previously characterized Toll (Toll-1) and 18-wheeler (Toll-2). Here we describe the embryonic expression patterns of the seven Toll-like genes Toll-3 through Toll-9. We find that these genes have distinct expression domains and that their expression is dynamically changing throughout embryonic development. This complex and tissue-specific regulation of Toll-like gene expression strongly suggests a role in embryonic development for most Drosophila Tolls. The evolving picture on the Toll family members in Drosophila contrasts with that of mammalian Toll-like receptors, which are predominantly expressed in immune responsive cells where their activation occurs via microbial structural determinants.},
keywords = {Animals, Blotting, Cell Surface, Gene Expression Profiling, hoffmann, imler, Larva, M3i, Multigene Family, Northern, Receptors, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
The Drosophila transmembrane receptor Toll plays a key role in specifying the dorsoventral axis of the embryo. At later stages of development, it controls the immune response of the fly to fungal and Gram-positive bacterial infections. The Drosophila genome has a total of nine Toll-like genes, including the previously characterized Toll (Toll-1) and 18-wheeler (Toll-2). Here we describe the embryonic expression patterns of the seven Toll-like genes Toll-3 through Toll-9. We find that these genes have distinct expression domains and that their expression is dynamically changing throughout embryonic development. This complex and tissue-specific regulation of Toll-like gene expression strongly suggests a role in embryonic development for most Drosophila Tolls. The evolving picture on the Toll family members in Drosophila contrasts with that of mammalian Toll-like receptors, which are predominantly expressed in immune responsive cells where their activation occurs via microbial structural determinants.
Ligoxygakis Petros, Pelte Nadège, Hoffmann Jules A, Reichhart Jean-Marc
Activation of Drosophila Toll during fungal infection by a blood serine protease Article de journal
Dans: Science, vol. 297, no. 5578, p. 114–116, 2002, ISSN: 1095-9203.
Résumé | Liens | BibTeX | Étiquettes: Animals, Cell Surface, Chromosome Mapping, Escherichia coli, Female, Gene Expression Regulation, Genes, Gram-Positive Cocci, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Male, Mutation, Protein Sorting Signals, Protein Structure, Receptors, reichhart, Serine Endopeptidases, Tertiary, Toll-Like Receptors
@article{ligoxygakis_activation_2002,
title = {Activation of Drosophila Toll during fungal infection by a blood serine protease},
author = {Petros Ligoxygakis and Nadège Pelte and Jules A Hoffmann and Jean-Marc Reichhart},
doi = {10.1126/science.1072391},
issn = {1095-9203},
year = {2002},
date = {2002-07-01},
journal = {Science},
volume = {297},
number = {5578},
pages = {114--116},
abstract = {Drosophila host defense to fungal and Gram-positive bacterial infection is mediated by the Spaetzle/Toll/cactus gene cassette. It has been proposed that Toll does not function as a pattern recognition receptor per se but is activated through a cleaved form of the cytokine Spaetzle. The upstream events linking infection to the cleavage of Spaetzle have long remained elusive. Here we report the identification of a central component of the fungal activation of Toll. We show that ethylmethane sulfonate-induced mutations in the persephone gene, which encodes a previously unknown serine protease, block induction of the Toll pathway by fungi and resistance to this type of infection.},
keywords = {Animals, Cell Surface, Chromosome Mapping, Escherichia coli, Female, Gene Expression Regulation, Genes, Gram-Positive Cocci, Hemolymph, hoffmann, Hypocreales, Insect, Insect Proteins, M3i, Male, Mutation, Protein Sorting Signals, Protein Structure, Receptors, reichhart, Serine Endopeptidases, Tertiary, Toll-Like Receptors},
pubstate = {published},
tppubtype = {article}
}
Drosophila host defense to fungal and Gram-positive bacterial infection is mediated by the Spaetzle/Toll/cactus gene cassette. It has been proposed that Toll does not function as a pattern recognition receptor per se but is activated through a cleaved form of the cytokine Spaetzle. The upstream events linking infection to the cleavage of Spaetzle have long remained elusive. Here we report the identification of a central component of the fungal activation of Toll. We show that ethylmethane sulfonate-induced mutations in the persephone gene, which encodes a previously unknown serine protease, block induction of the Toll pathway by fungi and resistance to this type of infection.
Hoffmann Jules A, Reichhart Jean-Marc
Drosophila innate immunity: an evolutionary perspective Article de journal
Dans: Nat. Immunol., vol. 3, no. 2, p. 121–126, 2002, ISSN: 1529-2908.