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Carnesecchi E, Langezaal I, Browne P, Batista-Leite S, Campia I, Coecke S, Dagallier B, Deceuninck P, Dorne JLC, Tarazona JV, Le Goff F, Leinala E, Morath S, Munn S, Richardson J, Paini A, Wittwehr C. OECD harmonised template 201: Structuring and reporting mechanistic information to foster the integration of new approach methodologies for hazard and risk assessment of chemicals. Regul Toxicol Pharmacol 2023:105426. [PMID: 37277057 DOI: 10.1016/j.yrtph.2023.105426] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 05/31/2023] [Accepted: 06/02/2023] [Indexed: 06/07/2023]
Abstract
In the European Union, the Chemicals Strategy for Sustainability (CSS) highlights the need to enhance the identification and assessment of substances of concern while reducing animal testing, thus fostering the development and use of New Approach Methodologies (NAMs) such as in silico, in vitro and in chemico. In the United States, the Tox21 strategy aims at shifting toxicological assessments away from traditional animal studies towards target-specific, mechanism-based and biological observations mainly obtained by using NAMs. Many other jurisdictions around the world are also increasing the use of NAMs. Hence, the provision of dedicated non-animal toxicological data and reporting formats as a basis for chemical risk assessment is necessary. Harmonising data reporting is crucial when aiming at re-using and sharing data for chemical risk assessment across jurisdictions. The OECD has developed a series of OECD Harmonised Templates (OHT), which are standard data formats designed for reporting information used for the risk assessment of chemicals relevant to their intrinsic properties, including effects on human health (e.g., toxicokinetics, skin sensitisation, repeated dose toxicity) and the environment (e.g., toxicity to test species and wildlife, biodegradation in soil, metabolism of residues in crops). The objective of this paper is to demonstrate the applicability of the OHT standard format for reporting information under various chemical risk assessment regimes, and to provide users with practical guidance on the use of OHT 201, in particular to report test results on intermediate effects and mechanistic information.
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Affiliation(s)
- Edoardo Carnesecchi
- Organisation for Economic Co-operation and Development (OECD), Environment Directorate, 75775, Paris CEDEX 16, France.
| | | | - Patience Browne
- Organisation for Economic Co-operation and Development (OECD), Environment Directorate, 75775, Paris CEDEX 16, France
| | | | - Ivana Campia
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Sandra Coecke
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Bertrand Dagallier
- Organisation for Economic Co-operation and Development (OECD), Environment Directorate, 75775, Paris CEDEX 16, France
| | | | - Jean Lou Cm Dorne
- European Food Safety Authority (EFSA), Via Carlo Magno, 1A, 43126, Parma, Italy
| | - Jose V Tarazona
- European Food Safety Authority (EFSA), Via Carlo Magno, 1A, 43126, Parma, Italy
| | - Francois Le Goff
- European Chemicals Agency (ECHA), Telakkakatu 6, P.O. Box 400, FI-0012, Helsinki, Finland
| | - Eeva Leinala
- Organisation for Economic Co-operation and Development (OECD), Environment Directorate, 75775, Paris CEDEX 16, France
| | | | - Sharon Munn
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Jane Richardson
- European Food Safety Authority (EFSA), Via Carlo Magno, 1A, 43126, Parma, Italy
| | - Alicia Paini
- European Commission, Joint Research Centre (JRC), Ispra, Italy
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Coecke S, Ahr H, Blaauboer BJ, Bremer S, Casati S, Castell J, Combes R, Corvi R, Crespi CL, Cunningham ML, Elaut G, Eletti B, Freidig A, Gennari A, Ghersi-Egea JF, Guillouzo A, Hartung T, Hoet P, Ingelman-Sundberg M, Munn S, Janssens W, Ladstetter B, Leahy D, Long A, Meneguz A, Monshouwer M, Morath S, Nagelkerke F, Pelkonen O, Ponti J, Prieto P, Richert L, Sabbioni E, Schaack B, Steiling W, Testai E, Vericat JA, Worth A. Metabolism: A Bottleneck in In Vitro Toxicological Test Development. Altern Lab Anim 2019; 34:49-84. [PMID: 16522150 DOI: 10.1177/026119290603400113] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Sandra Coecke
- ECVAM, Institute for Health and Consumer Protection, European Commission Joint Research Centre, Ispra, Italy
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3
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Gouliarmou V, Lostia AM, Coecke S, Bernasconi C, Bessems J, Dorne JL, Ferguson S, Testai E, Remy UG, Brian Houston J, Monshouwer M, Nong A, Pelkonen O, Morath S, Wetmore BA, Worth A, Zanelli U, Zorzoli MC, Whelan M. Establishing a systematic framework to characterise in vitro methods for human hepatic metabolic clearance. Toxicol In Vitro 2018; 53:233-244. [DOI: 10.1016/j.tiv.2018.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 07/17/2018] [Accepted: 08/08/2018] [Indexed: 12/26/2022]
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Hoffmann W, Gradinaru J, Farcal L, Caul-Futy M, Huang S, Wiszniewski L, Parissis N, Morath S, Fortaner S, Cole T, Reginato E, Carrupt PA, Constant S, Coecke S. Establishment of a Human 3D Tissue-Based Assay for Upper Respiratory Tract Absorption. ACTA ACUST UNITED AC 2018. [DOI: 10.1089/aivt.2017.0035] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Wiebke Hoffmann
- European Commission Joint Research Centre, The European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Ispra, Italy
- University of Vienna, Institute of Nutritional and Physiological Chemistry, Vienna, Austria
| | - Julieta Gradinaru
- Pharmacochemistry Unit, School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Lucian Farcal
- European Commission Joint Research Centre, The European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Ispra, Italy
- Douglas Connect GmbH, Basel, Switzerland
| | | | | | | | - Nikolaos Parissis
- European Commission Joint Research Centre, The European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Ispra, Italy
| | - Siegfried Morath
- European Commission Joint Research Centre, The European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Ispra, Italy
| | - Salvador Fortaner
- European Commission Joint Research Centre, The European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Ispra, Italy
| | - Thomas Cole
- European Commission Joint Research Centre, The European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Ispra, Italy
| | - Emilie Reginato
- Pharmacochemistry Unit, School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Pierre-Alain Carrupt
- Pharmacochemistry Unit, School of Pharmaceutical Sciences, University of Geneva, University of Lausanne, Geneva, Switzerland
| | | | - Sandra Coecke
- European Commission Joint Research Centre, The European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Ispra, Italy
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Abstract
The role of lipoteichoic acids (LTAs) from Gram-positive bacteria as immunostimulatory molecules was controversial for many years, as inadequate preparation methods as well as heterogeneous and endotoxin-contaminated commercial preparations led to conflicting results. An improved purification methodology for LTA now yields potent bioactive and chemically defined material, which is currently being characterized in various models. A synthetic analogue of Staphylococcus aureus LTA has proven the structure/function relationship. The key role of D-alanine esters for the immune response of LTA was confirmed by synthetic derivatives. The glycolipid anchor of LTA plays a central role analogous to the lipid A of LPS. Methodological aspects and criteria for quality assessment of LTA preparations are discussed.
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Affiliation(s)
- Siegfried Morath
- Department of Biochemical Pharmacology, University of Konstanz, Konstanz, Germany, European Center for the Validation of Alternative Methods (ECVAM), Joint Research Center, Ispra, Italy
| | - Sonja von Aulock
- Department of Biochemical Pharmacology, University of Konstanz, Konstanz, Germany
| | - Thomas Hartung
- Department of Biochemical Pharmacology, University of Konstanz, Konstanz, Germany, , European Center for the Validation of Alternative Methods (ECVAM), Joint Research Center, Ispra, Italy
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Kaiser C, Stoll I, Ataseven B, Morath S, Schaff J, Eiermann W. Vaginale Hysterektomie und beidseitige Adnexektomie in interdisziplinärem Konzept bei Frau zu Mann – Transsexualismus. HANDCHIR MIKROCHIR P 2011; 43:240-5. [DOI: 10.1055/s-0030-1267241] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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Morath S, Papadopulos N, Schaff J. Operatives Management und Techniken der Mastektomie bei Frau-zu-Mann Transsexuellen. HANDCHIR MIKROCHIR P 2011; 43:232-9. [DOI: 10.1055/s-0031-1273735] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Dehus O, Pfitzenmaier M, Stuebs G, Fischer N, Schwaeble W, Morath S, Hartung T, Geyer A, Hermann C. Growth temperature-dependent expression of structural variants of Listeria monocytogenes lipoteichoic acid. Immunobiology 2011; 216:24-31. [PMID: 20413180 DOI: 10.1016/j.imbio.2010.03.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 03/12/2010] [Accepted: 03/14/2010] [Indexed: 11/23/2022]
Abstract
Investigating the expression of lipoteichoic acid (LTA) from Listeria monocytogenes, we found two distinct structural variants of LTA (LTA1 and LTA2) using NMR and MS technology. While both LTA consisted of a poly-glycerophosphate backbone (differing in length) bound via a disaccharide to a diacyl-glycerol moiety, one LTA type (LTA2) possessed a second diacyl-glycerol moiety linked to the disaccharide via a phosphodiester. As examined in vitro, LTA2 in contrast to LTA1 failed to activate the L-ficolin dependent pathway of complement. Most interestingly, growth temperature had a strong influence on the expression levels of LTA1 and LTA2 in the cell wall: while the amount of LTA1 was comparable, the expression of LTA2 was low when Listeria had grown at room temperature (ratio of LTA1 to LTA2 was 1:0.06), but increased when Listeria had been cultivated at 37°C (ratio of LTA1 to LTA2 was 1:0.68). The observed shift in LTA expression, probably accompanying the switch from the saprophytic to the virulent entity, indicates an important adaptation to the different structural requirements inside the host cells.
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Affiliation(s)
- Oliver Dehus
- Biochemical Pharmacology, University of Konstanz, Konstanz 78467, Germany.
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9
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Kaiser C, Stoll I, Ataseven B, Morath S, Schaff J, Eiermann W. Vaginale Hysterektomie und bilaterale Adnexektomie in interdisziplinärem Konzept bei Female-to-Male (FtM) Transsexualismus. Geburtshilfe Frauenheilkd 2010. [DOI: 10.1055/s-0030-1269941] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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10
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Buzanska L, Ruiz A, Ceriotti L, Sobanski T, Hogberg H, Morath S, Vojnits K, Zychowicz M, Whelan M, Colpo P, Rossi F, Coecke S. Stem cells in neurotoxicology: Human in vitro model combined with emerging technologies. Toxicol Lett 2008. [DOI: 10.1016/j.toxlet.2008.06.835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Kramer NE, Hasper HE, van den Bogaard PTC, Morath S, de Kruijff B, Hartung T, Smid EJ, Breukink E, Kok J, Kuipers OP. Increased D-alanylation of lipoteichoic acid and a thickened septum are main determinants in the nisin resistance mechanism of Lactococcus lactis. Microbiology (Reading) 2008; 154:1755-1762. [PMID: 18524930 DOI: 10.1099/mic.0.2007/015412-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Nisin is a post-translationally modified antimicrobial peptide produced by Lactococcus lactis which binds to lipid II in the membrane to form pores and inhibit cell-wall synthesis. A nisin-resistant (Nis(R)) strain of L. lactis, which is able to grow at a 75-fold higher nisin concentration than its parent strain, was investigated with respect to changes in the cell wall. Direct binding studies demonstrated that less nisin was able to bind to lipid II in the membranes of L. lactis Nis(R) than in the parent strain. In contrast to vancomycin binding, which showed ring-like binding, nisin was observed to bind in patches close to cell-division sites in both the wild-type and the Nis(R) strains. Comparison of modifications in lipoteichoic acid of the L. lactis strains revealed an increase in d-alanyl esters and galactose as substituents in L. lactis Nis(R), resulting in a less negatively charged cell wall. Moreover, the cell wall displays significantly increased thickness at the septum. These results indicate that shielding the membrane and thus the lipid II molecule, thereby decreasing abduction of lipid II and subsequent pore-formation, is a major defence mechanism of L. lactis against nisin.
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Affiliation(s)
- Naomi E Kramer
- Department of Biochemistry of Membranes, Center for Biomembranes and Lipid Enzymology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.,Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
| | - Hester E Hasper
- Department of Biochemistry of Membranes, Center for Biomembranes and Lipid Enzymology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Patrick T C van den Bogaard
- Eukaryotic Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
| | - Siegfried Morath
- European Commission, Joint Research Centre, IHCP, European Centre for the Validation of Alternative Methods, 21020 Ispra, Italy
| | - Ben de Kruijff
- Department of Biochemistry of Membranes, Center for Biomembranes and Lipid Enzymology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Thomas Hartung
- European Commission, Joint Research Centre, IHCP, European Centre for the Validation of Alternative Methods, 21020 Ispra, Italy
| | - Eddy J Smid
- NIZO Food Research, Flavour and Natural Ingredients Section, PO Box 20, 6710 BA Ede, The Netherlands
| | - Eefjan Breukink
- Department of Biochemistry of Membranes, Center for Biomembranes and Lipid Enzymology, Institute of Biomembranes, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Jan Kok
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
| | - Oscar P Kuipers
- Molecular Genetics Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, PO Box 14, 9750 AA Haren, The Netherlands
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Draing C, Traub S, Deininger S, Mang P, Möller HM, Manso M, Rossi F, Morath S, Hartung T, von Aulock S. Polypropylene glycol is a selective binding inhibitor for LTA and other structurally related TLR2 agonists. Eur J Immunol 2008; 38:797-808. [DOI: 10.1002/eji.200737466] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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13
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van Vliet E, Morath S, Eskes C, Linge J, Rappsilber J, Honegger P, Hartung T, Coecke S. A novel in vitro metabolomics approach for neurotoxicity testing, proof of principle for methyl mercury chloride and caffeine. Neurotoxicology 2008; 29:1-12. [DOI: 10.1016/j.neuro.2007.09.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 09/12/2007] [Accepted: 09/19/2007] [Indexed: 10/22/2022]
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Liljeroos M, Vuolteenaho R, Morath S, Hartung T, Hallman M, Ojaniemi M. Bruton's tyrosine kinase together with PI 3-kinase are part of Toll-like receptor 2 multiprotein complex and mediate LTA induced Toll-like receptor 2 responses in macrophages. Cell Signal 2007; 19:625-33. [PMID: 17020802 DOI: 10.1016/j.cellsig.2006.08.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Revised: 08/15/2006] [Accepted: 08/21/2006] [Indexed: 12/31/2022]
Abstract
Lipoteichoic acid (LTA) of Gram-positive bacteria initiates innate immune responses via Toll-like receptor-2 (TLR2), resulting in the activation of intracellular signaling and production of inflammatory cytokines in macrophages. Although Bruton's tyrosine kinase (Btk) is biologically important molecule implicated in immune regulation and recently in TLR signaling its importance for LTA-TLR2 mediated responses has not been evaluated. In this study, we detected Btk in the LTA signaling complex with TLR2 and PI 3-kinase (PI3K). The constitutive interaction of these proteins was mediated via PI3K Src homology (SH3) -domain. Both Btk and PI3K were activated by LTA stimulation and the LTA induced cytokine expression was differentially modulated by these kinases. LTA induced the activation of nuclear factor kappaB (NFkappaB), however, only Btk inhibition affected the LTA induced Ser536 phosphorylation and DNA-binding of NFkappaB. In conclusion, our results demonstrate that Btk and PI3K occupy important roles in TLR2-induced activation of macrophages, resulting in selective regulation of cytokines.
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Affiliation(s)
- M Liljeroos
- Department of Pediatrics, Biocenter Oulu, P.O. Box 5000, FIN-90014, University of Oulu, Oulu, Finland
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Triantafilou M, Gamper FGJ, Haston RM, Mouratis MA, Morath S, Hartung T, Triantafilou K. Membrane sorting of toll-like receptor (TLR)-2/6 and TLR2/1 heterodimers at the cell surface determines heterotypic associations with CD36 and intracellular targeting. J Biol Chem 2006; 281:31002-11. [PMID: 16880211 DOI: 10.1074/jbc.m602794200] [Citation(s) in RCA: 343] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Toll-like receptors (TLRs) are receptors of the innate immune system responsible for recognizing pathogen-associated molecular patterns. TLR2 seems to be the most promiscuous TLR receptor able to recognize the most diverse set of pathogen-associated patterns. Its promiscuity has been attributed to its unique ability to heterodimerize with TLRs 1 and 6 and, most recently, to its association with CD36 in response to diacylated lipoproteins. Thus, it seems that TLR2 forms receptor clusters in response to different microbial ligands. In this study we investigated TLR2 cell surface heterotypic interactions in response to different ligands as well as internalization and intracellular trafficking. Our data show that TLR2 forms heterodimers with TLR1 and TLR6 and that these heterodimer pre-exist and are not induced by the ligand. Upon stimulation by the specific ligand, these heterodimers are recruited within lipid rafts. In contrast, heterotypic associations of TLR2/6 with CD36 are not preformed and are ligand-induced. All TLR2 receptor clusters accumulate in lipid rafts and are targeted to the Golgi apparatus. This localization and targeting is ligand-specific. Activation occurs at the cell surface, and the observed trafficking is independent of signaling.
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Affiliation(s)
- Martha Triantafilou
- Infection and Immunity Group, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9QG, United Kingdom
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Lotz S, Starke A, Ziemann C, Morath S, Hartung T, Solbach W, Laskay T. Beta-lactam antibiotic-induced release of lipoteichoic acid from Staphylococcus aureus leads to activation of neutrophil granulocytes. Ann Clin Microbiol Antimicrob 2006; 5:15. [PMID: 16803618 PMCID: PMC1550251 DOI: 10.1186/1476-0711-5-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Accepted: 06/27/2006] [Indexed: 11/10/2022] Open
Abstract
Background Polymorphonuclear neutrophil granulocytes (PMN) are phagocytes of the first line of antimicrobial defense. Previously we demonstrated that lipoteichoic acid (LTA) from Staphylococcus aureus (S. aureus) directly activates neutrophil granulocytes. Others have reported that exposure of S. aureus to β-lactam antibiotics leads to LTA release. In the present study we addressed the question whether exposure of S. aureus to β-lactam antibiotics or antibiotics of other groups results in the generation of PMN-stimulating activity and whether this activity can be attributed to LTA. Methods S. aureus were exposed to flucloxacillin, a β-lactam antibiotic or to the protein synthesis-inhibitors erythromycin and gentamicin, or to ciprofloxacin, a gyrase inhibitor. Supernatants of the antibiotic-treated bacteria were assayed for their LTA content and for their effect on PMN functions. Results We observed that exposure of S. aureus to flucloxacillin and, to a lesser degree to ciprofloxacin, but not to erythromycin or gentamicin led to LTA release. Co-incubation of neutrophil granulocytes with LTA-containing supernatants led to PMN activation as assed by morphological changes, release of IL-8, delay of spontaneous apoptosis and enhanced phagocytic activity. Depletion of LTA from the supernatants markedly reduced their PMN-activating capacity. Conclusion The findings suggest that, via the activation of PMN, antibiotic-induced LTA release from S. aureus leads to enhanced antimicrobial activity of the innate immune defense mechanisms.
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Affiliation(s)
- Sonja Lotz
- Institute for Medical Microbiology and Hygiene, University of Lübeck, Germany
| | - Andrea Starke
- Institute for Medical Microbiology and Hygiene, University of Lübeck, Germany
| | - Christian Ziemann
- Institute for Medical Microbiology and Hygiene, University of Lübeck, Germany
| | | | - Thomas Hartung
- ECVAM, Joint Research Center, Ispra, Italy
- Department of Biochemical Pharmacology, University of Konstanz, Germany
| | - Werner Solbach
- Institute for Medical Microbiology and Hygiene, University of Lübeck, Germany
| | - Tamás Laskay
- Institute for Medical Microbiology and Hygiene, University of Lübeck, Germany
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Küpper FC, Gaquerel E, Boneberg EM, Morath S, Salaün JP, Potin P. Early events in the perception of lipopolysaccharides in the brown alga Laminaria digitata include an oxidative burst and activation of fatty acid oxidation cascades. J Exp Bot 2006; 57:1991-9. [PMID: 16690625 DOI: 10.1093/jxb/erj146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
This study provides evidence that bacterial lipopolysaccharides can be strong triggers of early events of defence reactions in the brown algal kelp Laminaria digitata, constituting the first report of a biological activity of this class of macromolecules in a marine alga. The early events include an oxidative burst, release of free saturated and unsaturated fatty acids (FFAs) and accumulation of oxylipins such as 13-hydroxyoctadecatrienoic acid and 15-hydroxyeicosapentaenoic acid. The formation of reactive oxygen species can be inhibited by diphenylene iodonium, suggesting that the source is an NAD(P)H oxidase and is similar to the oxidative burst in neutrophils and terrestrial plants. In addition and besides triggering an oxidative burst, the hypolipidemic drug clofibrate also induces the release of FFAs, to a lesser extent than lipopolysaccharides, but it does not induce oxylipin production. Other strong inducers of the oxidative burst in Laminaria such as oligoguluronates could not induce the release of FFAs nor oxylipin production. These results suggest that different signalling pathways are involved in the induction of the oxidative burst and oxylipin production.
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Affiliation(s)
- Frithjof C Küpper
- Station Biologique, UMR 7139 CNRS-UPMC and LIA DIAMS, BP 74, Roscoff, Brittany, France.
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18
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Palumbo E, Deghorain M, Cocconcelli PS, Kleerebezem M, Geyer A, Hartung T, Morath S, Hols P. D-alanyl ester depletion of teichoic acids in Lactobacillus plantarum results in a major modification of lipoteichoic acid composition and cell wall perforations at the septum mediated by the Acm2 autolysin. J Bacteriol 2006; 188:3709-15. [PMID: 16672624 PMCID: PMC1482858 DOI: 10.1128/jb.188.10.3709-3715.2006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Accepted: 02/27/2006] [Indexed: 11/20/2022] Open
Abstract
The insertional inactivation of the dlt operon from Lactobacillus plantarum NCIMB8826 had a strong impact on lipoteichoic acid (LTA) composition, resulting in a major reduction in D-alanyl ester content. Unexpectedly, mutant LTA showed high levels of glucosylation and were threefold longer than wild-type LTA. The dlt mutation resulted in a reduced growth rate and increased cell lysis during the exponential and stationary growth phases. Microscopy analysis revealed increased cell length, damaged dividing cells, and perforations of the envelope in the septal region. The observed defects in the separation process, cell envelope perforation, and autolysis of the dlt mutant could be partially attributed to the L. plantarum Acm2 peptidoglycan hydrolase.
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Affiliation(s)
- Emmanuelle Palumbo
- Unité de Génétique, Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-La-Neuve, Belgium.
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19
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Hattar K, Grandel U, Moeller A, Fink L, Iglhaut J, Hartung T, Morath S, Seeger W, Grimminger F, Sibelius U. Lipoteichoic acid (LTA) from Staphylococcus aureus stimulates human neutrophil cytokine release by a CD14-dependent, Toll-like-receptor-independent mechanism: Autocrine role of tumor necrosis factor-α in mediating LTA-induced interleukin-8 generation. Crit Care Med 2006; 34:835-41. [PMID: 16521278 DOI: 10.1097/01.ccm.0000202204.01230.44] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE In sepsis, Gram-positive and Gram-negative bacteria provoke similar inflammatory processes. Whereas lipopolysaccharides (LPSs) are acknowledged as the principal immunostimulatory components of Gram-negative bacteria, the effect of the Gram-positive cell wall component lipoteichoic acid (LTA) is less well characterized. In the present study, we investigated the effect of highly purified LTA from Staphylococcus aureus on cytokine generation by isolated human neutrophils. SUBJECTS Isolated human neutrophils from healthy volunteers. INTERVENTIONS Incubation of neutrophils with purified LTA from S. aureus in the absence or presence of interleukin (IL)-10, anti-CD14, or anti-Toll-like-receptor antibodies. MEASUREMENTS Measurement of tumor necrosis factor (TNF)-alpha, IL-1beta, and IL-8 by enzyme-linked immunosorbent assay. Analysis of IL-8 mRNA by reverse transcriptase polymerase chain reaction. CONCLUSIONS The LTA challenge provoked a dramatic release of cytokines, with an early appearance of TNF-alpha and IL-1beta and a delayed liberation of IL-8. The first phase of IL-8 production was induced directly by LTA, whereas the second phase was endogenously mediated by TNF-alpha, as it was largely abrogated by neutralizing anti-TNF-alpha antibodies. In contrast, IL1-beta was not involved in LTA-induced IL-8 generation. Interestingly, the late phase of IL-8 generation could also be attenuated by exogenous IL-10, probably as a consequence of its downregulatory effects on TNF-alpha generation. When investigating the mechanism of LTA-induced cellular activation, activity-neutralizing antibodies demonstrated that CD14 was involved in LTA-mediated neutrophil cytokine generation. Using antibodies that neutralize the activity of Toll-like receptor 2 (TLR2) or 4 (TLR4), we also show that CD14-dependent, LTA-induced neutrophil activation did not proceed via TLR2- or TLR4-mediated pathways. In conclusion, LTA is a potent activator of human neutrophil cytokine generation, with the synthesis of the chemokine IL-8 being largely dependent on TNF-alpha generation in an autocrine fashion. This LTA-induced effect was inhibited by IL-10, dependent on CD14, and independent of TLR 2 or 4.
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Affiliation(s)
- Katja Hattar
- Department of Internal Medicine, University of Giessen Lung Center, Germany
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20
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Abstract
The role of lipoteichoic acids (LTAs) from Gram-positive bacteria as immunostimulatory molecules was controversial for many years, as inadequate preparation methods as well as heterogeneous and endotoxin-contaminated commercial preparations led to conflicting results. An improved purification methodology for LTA now yields potent bioactive and chemically defined material, which is currently being characterized in various models. A synthetic analogue of Staphylococcus aureus LTA has proven the structure/function relationship. The key role of D-alanine esters for the immune response of LTA was confirmed by synthetic derivatives. The glycolipid anchor of LTA plays a central role analogous to the lipid A of LPS. Methodological aspects and criteria for quality assessment of LTA preparations are discussed.
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Affiliation(s)
- Siegfried Morath
- Department of Biochemical Pharmacology, University of Konstanz, Konstanz, Germany
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21
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Grandel U, Hopf M, Buerke M, Hattar K, Heep M, Fink L, Bohle RM, Morath S, Hartung T, Pullamsetti S, Schermuly RT, Seeger W, Grimminger F, Sibelius U. Mechanisms of Cardiac Depression Caused by Lipoteichoic Acids From
Staphylococcus aureus
in Isolated Rat Hearts. Circulation 2005; 112:691-8. [PMID: 16043646 DOI: 10.1161/circulationaha.104.503938] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Lipoteichoic acid (LTA) represents a major virulence factor in gram-positive sepsis.
Methods and Results—
In the present study we perfused isolated rat hearts for 180 minutes with highly purified LTA from
Staphylococcus aureus
. A progressive decline of left ventricular contractile function paralleled by the expression of myocardial tumor necrosis factor-α (TNF-α) mRNA and protein as well as the release of TNF-α into the perfusate was observed in LTA-perfused hearts. Employment of an anti–TNF-α antibody completely prevented the loss in contractile function. When CD14, a prominent pathogen recognition receptor, was blocked by a specific antibody, induction of TNF-α mRNA and protein release as well as the associated cardiodepression was diminished in response to LTA. Synthesis of TNF-α protein was located to interstitial cells of LTA-challenged hearts as detected by immunohistochemistry. Besides progressive cardiodepression, coronary perfusion pressure (CPP) was moderately increased in LTA-perfused hearts. This was accompanied by the release of thromboxane A
2
(TXA
2
) into the perfusate and the induction of cyclooxygenase (Cox)-2 mRNA and protein in the myocardium. Blocking of TXA
2
by the nonspecific Cox inhibitor indomethacin, the thromboxane receptor antagonist daltroban, or the selective Cox-2 inhibitor NS-398 prevented the increase in CPP.
Conclusions—
LTA causes cardiac depression by activating myocardial TNF-α synthesis via CD14 and induces coronary vascular disturbances by activating Cox-2–dependent TXA
2
synthesis. These phenomena may contribute to cardiac depression in gram-positive sepsis.
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Affiliation(s)
- Ulrich Grandel
- Department of Internal Medicine, Justus Liebig University, Giessen, Germany
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22
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Grangette C, Nutten S, Palumbo E, Morath S, Hermann C, Dewulf J, Pot B, Hartung T, Hols P, Mercenier A. Enhanced antiinflammatory capacity of a Lactobacillus plantarum mutant synthesizing modified teichoic acids. Proc Natl Acad Sci U S A 2005; 102:10321-6. [PMID: 15985548 PMCID: PMC1177390 DOI: 10.1073/pnas.0504084102] [Citation(s) in RCA: 322] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Teichoic acids (TAs), and especially lipoteichoic acids (LTAs), are one of the main immunostimulatory components of pathogenic Gram-positive bacteria. Their contribution to the immunomodulatory properties of commensal bacteria and especially of lactic acid bacteria has not yet been investigated in detail. To evaluate the role of TAs in the interaction between lactic acid bacteria and the immune system, we analyzed the antiinflammatory properties of a mutant of Lactobacillus plantarum NCIMB8826 affected in the TA biosynthesis pathway both in vitro (mononuclear cells stimulation) and in vivo (murine model of colitis). This Dlt- mutant was found to incorporate much less D-Ala in its TAs than the WT strain. This defect significantly impacted the immunomodulation reactions induced by the bacterium, as shown by a dramatically reduced secretion of proinflammatory cytokines by peripheral blood mononuclear cells and monocytes stimulated by the Dlt- mutant as compared with the parental strain. Concomitantly, a significant increase in IL-10 production was stimulated by the Dlt- mutant in comparison with the WT strain. Moreover, the proinflammatory capacity of L. plantarum-purified LTA was found to be Toll-like receptor 2-dependent. Consistent with the in vitro results, the Dlt- mutant was significantly more protective in a murine colitis model than its WT counterpart. The results indicated that composition of LTA within the whole-cell context of L. plantarum can modulate proinflammatory or antiinflammatory immune responses.
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Affiliation(s)
- Corinne Grangette
- Laboratoire de Bactériologie des Ecosytèmes, Institut Pasteur de Lille-Institut de Biologie de Lille, 59019 Lille Cedex, France.
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23
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Henneke P, Morath S, Uematsu S, Weichert S, Pfitzenmaier M, Takeuchi O, Müller A, Poyart C, Akira S, Berner R, Teti G, Geyer A, Hartung T, Trieu-Cuot P, Kasper DL, Golenbock DT. Role of Lipoteichoic Acid in the Phagocyte Response to Group BStreptococcus. J Immunol 2005; 174:6449-55. [PMID: 15879147 DOI: 10.4049/jimmunol.174.10.6449] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Group B Streptococcus (GBS) cell walls potently activate phagocytes by a largely TLR2-independent mechanism. In contrast, the cell wall component lipoteichoic acid (LTA) from diverse Gram-positive bacterial species has been shown to engage TLR2. In this study we examined the role of LTA from GBS in phagocyte activation and the requirements for TLR-LTA interaction. Using cells from knockout mice and genetic complementation in epithelial cells we found that highly pure LTA from both GBS and Staphylococcus aureus interact with TLR2 and TLR6, but not TLR1, in contrast to previous reports. Furthermore, NF-kappaB activation by LTA required the integrity of two putative PI3K binding domains within TLR2 and was inhibited by wortmannin, indicating an essential role for PI3K in cellular activation by LTA. However, LTA from GBS proved to be a relatively weak stimulus of phagocytes containing approximately 20% of the activity observed with LTA from Staphylococcus aureus. Structural analysis by nuclear magnetic resonance spectrometry revealed important differences between LTA from GBS and S. aureus, specifically differences in glycosyl linkage, in the glycolipid anchor and a lack of N-acetylglucosamine substituents of the glycerophosphate backbone. Furthermore, GBS expressing LTA devoid of d-alanine residues, that are essential within immune activation by LTA, exhibited similar inflammatory potency as GBS with alanylated LTA. In conclusion, LTA from GBS is a TLR2/TLR6 ligand that might contribute to secreted GBS activity, but does not contribute significantly to GBS cell wall mediated macrophage activation.
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MESH Headings
- Alanine/genetics
- Alanine/metabolism
- Animals
- Cell Line
- Cells, Cultured
- Cytokines/metabolism
- Humans
- Inflammation Mediators/metabolism
- Lipopolysaccharides/chemistry
- Lipopolysaccharides/metabolism
- Lipopolysaccharides/pharmacology
- Macrophage Activation/genetics
- Macrophage Activation/immunology
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/metabolism
- Macrophages, Peritoneal/microbiology
- Membrane Glycoproteins/deficiency
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mutagenesis, Site-Directed
- NF-kappa B/metabolism
- Peptidoglycan/pharmacology
- Receptors, Cell Surface/deficiency
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/physiology
- Receptors, Immunologic/deficiency
- Receptors, Immunologic/genetics
- Receptors, Immunologic/physiology
- Staphylococcus aureus/chemistry
- Staphylococcus aureus/immunology
- Streptococcus agalactiae/genetics
- Streptococcus agalactiae/immunology
- Streptococcus agalactiae/metabolism
- Teichoic Acids/chemistry
- Teichoic Acids/metabolism
- Teichoic Acids/pharmacology
- Toll-Like Receptor 2
- Toll-Like Receptor 6
- Tyrosine/chemistry
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Affiliation(s)
- Philipp Henneke
- Zentrum für Kinderheilkunde und Jugendmedizin, Albert-Ludwigs Universität Freiburg, Freiburg, Germany.
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24
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Lund S, Porzgen P, Mortensen AL, Hasseldam H, Bozyczko-Coyne D, Morath S, Hartung T, Bianchi M, Ghezzi P, Bsibsi M, Dijkstra S, Leist M. Inhibition of microglial inflammation by the MLK inhibitor CEP-1347. J Neurochem 2005; 92:1439-51. [PMID: 15748162 DOI: 10.1111/j.1471-4159.2005.03014.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
CEP-1347 is a potent inhibitor of the mixed lineage kinases (MLKs), a distinct family of mitogen-activated protein kinase kinase kinases (MAPKKK). It blocks the activation of the c-Jun/JNK apoptotic pathway in neurons exposed to various stressors and attenuates neurodegeneration in animal models of Parkinson's disease (PD). Microglial activation may involve kinase pathways controlled by MLKs and might contribute to the pathology of neurodegenerative diseases. Therefore, the possibility that CEP-1347 modulates the microglial inflammatory response [tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and monocyte chemotactic protein-1 (MCP-1)] was explored. Indeed, the MLK inhibitor CEP-1347 reduced cytokine production in primary cultures of human and murine microglia, and in monocyte/macrophage-derived cell lines, stimulated with various endotoxins or the plaque forming peptide Abeta1-40. Moreover, CEP-1347 inhibited brain TNF production induced by intracerebroventricular injection of lipopolysaccharide in mice. As expected from a MLK inhibitor, CEP-1347 acted upstream of p38 and c-Jun activation in microglia by dampening the activity of both pathways. These data imply MLKs as important, yet unrecognized, modulators of microglial inflammation, and demonstrate a novel anti-inflammatory potential of CEP-1347.
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Affiliation(s)
- Søren Lund
- Disease Biology, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark.
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25
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Triantafilou M, Morath S, Mackie A, Hartung T, Triantafilou K. Lateral diffusion of Toll-like receptors reveals that they are transiently confined within lipid rafts on the plasma membrane. J Cell Sci 2005; 117:4007-14. [PMID: 15286178 DOI: 10.1242/jcs.01270] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The innate immune system utilises pattern recognition receptors in order to recognise microbial conserved molecular patterns. The family of Toll-like receptors (TLRs) has been shown to act as the main pattern recognition receptors for the innate immune system. Using biochemical as well as fluorescence imaging techniques, TLR2 and TLR4 were found to be recruited within microdomains upon stimulation by bacterial products. Furthermore their lateral diffusion in the cell membrane as determined by fluorescence recovery after photobleaching revealed that upon stimulation by bacterial products TLRs encounter barriers to their lateral movement, thus supporting the notion that specialised domains on the plasma membrane facilitate the innate recognition.
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Affiliation(s)
- Martha Triantafilou
- Infection and Immunity Group, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9QG, UK
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26
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Figueroa-Perez I, Stadelmaier A, Morath S, Hartung T, Schmidt RR. Synthesis of structural variants of Staphylococcus aureus lipoteichoic acid (LTA). ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.tetasy.2004.11.070] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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27
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von Aulock S, Morath S, Hareng L, Knapp S, van Kessel KPM, van Strijp JAG, Hartung T. Lipoteichoic acid from Staphylococcus aureus is a potent stimulus for neutrophil recruitment. Immunobiology 2004; 208:413-22. [PMID: 14748514 DOI: 10.1078/0171-2985-00285] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Lipoteichoic acid (LTA) is a major immunostimulatory principle of Gram-positive bacteria. Intranasal application of LTA from S. aureus to mice resulted in greatly increased neutrophil and macrophage counts in the bronchoalveolar lavage as well as increased levels of the chemokine KC. The potential of highly pure, bioactive LTA from S. aureus to induce neutrophil recruitment and activation was investigated further in the human system. Although neutrophils expressed the key known receptors, CD14, TLR2 and TLR6, LTA did not induce or prime neutrophils for oxidative burst, or release of chemokines, bactericidal permeability-increasing protein or myeloperoxidase. However, LTA induced a strong release of the chemoattractants LTB4, IL-8, C5a, MCP-1 and the colony-stimulating factor G-CSF in whole blood comparable to stimulation with the same concentration of LPS (S. abortus equi). Further, the cytokine and chemoattractant pattern induced by LTA correlated well with that induced by live S. aureus of the same strain. LTA does not appear to activate neutrophils directly, but is a strong stimulus for the recruitment of phagocytes to the site of infection.
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Affiliation(s)
- Sonja von Aulock
- Biochemical Pharmacology, University of Konstanz, 78457 Konstanz, Germany
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28
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Triantafilou M, Manukyan M, Mackie A, Morath S, Hartung T, Heine H, Triantafilou K. Lipoteichoic Acid and Toll-like Receptor 2 Internalization and Targeting to the Golgi Are Lipid Raft-dependent. J Biol Chem 2004; 279:40882-9. [PMID: 15247273 DOI: 10.1074/jbc.m400466200] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Lipoteichoic acid (LTA), a key cell wall component of Gram-positive bacteria, seems to function as an immune activator with characteristics very similar to lipopolysaccharide from Gram-negative bacteria. It has been shown that LTA binds CD14 and triggers activation via Toll-like receptor 2, but whether the activation occurs at the cell surface or internalization is required to trigger signaling has yet to be demonstrated. In this work we have investigated LTA binding and internalization and found that LTA and its receptor molecules accumulate in lipid rafts and are subsequently targeted rapidly to the Golgi apparatus. This internalization seems to be lipid raft-dependent because raft-disrupting drugs inhibited LTA/Toll-like receptor 2 colocalization in the Golgi. Similarly to lipopolysaccharide, LTA activation occurs at the cell surface, and the observed trafficking is independent of signaling.
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Affiliation(s)
- Martha Triantafilou
- Infection and Immunity Group, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, United Kingdom
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29
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Mattsson E, Hartung T, Morath S, Egesten A. Highly purified lipoteichoic acid from Staphylococcus aureus induces procoagulant activity and tissue factor expression in human monocytes but is a weak inducer in whole blood: comparison with peptidoglycan. Infect Immun 2004; 72:4322-6. [PMID: 15213184 PMCID: PMC427414 DOI: 10.1128/iai.72.7.4322-4326.2004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipoteichoic acid from Staphylococcus aureus was a potent inducer of procoagulant activity in isolated mononuclear cells but not in whole blood. In contrast, staphylococcal peptidoglycan showed equal levels of potency in isolated mononuclear cells and whole blood, suggesting that peptidoglycan is an important inducer of procoagulant activity in severe sepsis involving gram-positive bacteria.
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Affiliation(s)
- Eva Mattsson
- Department of Clinical Microbiology, University Hospital Utrecht, Heidelberglaan 100, P.O. Box 85.500, 3508 GA Utrecht, Holland.
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30
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Traub S, Kubasch N, Morath S, Kresse M, Hartung T, Schmidt RR, Hermann C. Structural Requirements of Synthetic Muropeptides to Synergize with Lipopolysaccharide in Cytokine Induction. J Biol Chem 2004; 279:8694-700. [PMID: 14668350 DOI: 10.1074/jbc.m310556200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Muropeptides contribute to the recognition of bacteria by modulating immune responses: the structural requirements for adjuvant activity were described in the seventies. During the last years, our knowledge of bacterial pattern recognition has increased dramatically and the importance of the absence of contaminations in both muropeptide preparations and other bacterial stimuli has become clear. We investigated a panel of 15 synthetic Limulus-negative muropeptides, four of them synthesized for the first time, as to their potency to synergize with lipopolysaccharide (LPS) in cytokine induction in human whole blood. No muropeptide was capable of stimulating cytokine release from human blood. However, as little as 20 nM of the muropeptides N-acetyl-muramyl-l-alanyl-d-isoglutamine (muramyl dipeptide, M(AdiQ)), N-acetyl-glucosamine-muramyl dipeptide GM(AdiQ), or C(18)M(AdiQ), which carries a non-natural additional fatty acid, sufficed to induce an up to 3 log-order shift in tumor necrosis factor alpha-release in response to 100 pg/ml LPS. The release of interleukin-1beta, interleukin-6, and interleukin-10 was also significantly enhanced although to a lesser extent. The synergistic effect was stereoselective with M(AdiQ) being the minimal active principle. Synergy was also observed on the transcriptional level by means of real-time PCR. Smaller molecules like N-acetylmuramic acid (M), aM, carrying a naturally occurring 1,6-anhydro-bound in M or M(A), containing only the amino acid l-alanine neither synergized with LPS nor influenced the synergy of other muropeptides with LPS. In conclusion, these data show that nanomolar quantities of muropeptides dramatically potentiate LPS-induced monocyte activation. This has implications for pyrogenicity testing and endotoxemia in patients.
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Affiliation(s)
- Stephanie Traub
- Department of Biochemical Pharmacology, University of Konstanz, Konstanz 78457, Germany
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31
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Lynch NJ, Roscher S, Hartung T, Morath S, Matsushita M, Maennel DN, Kuraya M, Fujita T, Schwaeble WJ. L-ficolin specifically binds to lipoteichoic acid, a cell wall constituent of Gram-positive bacteria, and activates the lectin pathway of complement. J Immunol 2004; 172:1198-202. [PMID: 14707097 DOI: 10.4049/jimmunol.172.2.1198] [Citation(s) in RCA: 195] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The lectin pathway of complement is activated when a carbohydrate recognition complex and associated serine proteases binds to the surface of a pathogen. Three recognition subcomponents have been shown to form active initiation complexes: mannan-binding lectin (MBL), L-ficolin, and H-ficolin. The importance of MBL in antimicrobial host defense is well recognized, but the role of the ficolins remains largely undefined. This report shows that L-ficolin specifically binds to lipoteichoic acid (LTA), a cell wall component found in all Gram-positive bacteria. Immobilized LTA from Staphylococcus aureus binds L-ficolin complexes from sera, and these complexes initiate lectin pathway-dependent C4 turnover. C4 activation correlates with serum L-ficolin concentration, but not with serum MBL levels. L-ficolin binding and corresponding levels of C4 turnover were observed on LTA purified from other clinically important bacteria, including Streptococcus pyogenes and Streptococcus agalactiae. None of the LTA preparations bound MBL, H-ficolin, or the classical pathway recognition molecule, C1q.
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Affiliation(s)
- Nicholas J Lynch
- Department of Infection, Immunity and Inflammation, University of Leicester, University Road, Leicester LE1 9HN, U.K
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32
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Schröder NWJ, Morath S, Alexander C, Hamann L, Hartung T, Zähringer U, Göbel UB, Weber JR, Schumann RR. Lipoteichoic acid (LTA) of Streptococcus pneumoniae and Staphylococcus aureus activates immune cells via Toll-like receptor (TLR)-2, lipopolysaccharide-binding protein (LBP), and CD14, whereas TLR-4 and MD-2 are not involved. J Biol Chem 2003; 278:15587-94. [PMID: 12594207 DOI: 10.1074/jbc.m212829200] [Citation(s) in RCA: 462] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Lipoteichoic acid (LTA) derived from Streptococcus pneumoniae, purified employing a chloroform/methanol protocol, and from Staphylococcus aureus, prepared by the recently described butanol extraction procedure, was investigated regarding its interaction with lipopolysaccharide (LPS)-binding protein (LBP), CD14, Toll-like receptors (TLRs)-2 and -4, and MD-2. LTA from both organisms induced cytokine synthesis in human mononuclear phagocytes. Activation was LBP- and CD14-dependent, and formation of complexes of LTA with LBP and soluble CD14 as well as catalytic transfer of LTA to CD14 by LBP was verified by PhastGel(TM) native gel electrophoresis. Human embryonic kidney (HEK) 293/CD14 cells and Chinese hamster ovary (CHO) cells were responsive to LTA only after transfection with TLR-2. Additional transfection with MD-2 did not affect stimulation of these cells by LTA. Our data suggest that innate immune recognition of LTA via LBP, CD14, and TLR-2 represents an important mechanism in the pathogenesis of systemic complications in the course of infectious diseases brought about by the clinically most important Gram-positive pathogens. However, the involvement of TLR-4 and MD-2 in this process was ruled out.
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Affiliation(s)
- Nicolas W J Schröder
- Institut für Mikrobiologie und Hygiene, Universitätsklinikum Charité, Medizinische Fakultät der Humboldt-Universität zu Berlin, Dorotheenstrasse 96, D-10117 Berlin, Germany
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33
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Deininger S, Stadelmaier A, von Aulock S, Morath S, Schmidt RR, Hartung T. Definition of structural prerequisites for lipoteichoic acid-inducible cytokine induction by synthetic derivatives. J Immunol 2003; 170:4134-8. [PMID: 12682244 DOI: 10.4049/jimmunol.170.8.4134] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The controversy about the immune stimulatory properties of lipoteichoic acid (LTA) from Staphylococcus aureus was solved recently by showing decomposition and inactivation of LTA obtained by conventional purification strategies, as well as pronounced LPS contamination of commercial preparations. By introducing a novel preparation method, the structure of bioactive LTA was elucidated. This structure was confirmed by chemical synthesis. In this work, synthetic LTA derivatives were employed to study the structure-function relationship of cytokine induction in human monocytes. Synthetic LTA induced the same cytokine pattern as highly purified natural LTA. The gentiobiose core could be omitted without affecting bioactivity. The polyglycerophosphate backbone amplified the response to the lipid anchor ( approximately 100-fold) only when substituted with D-alanine, whereas alpha-D-N-acetylglucosamine substituents could be omitted. Replacing D-alanine substituents with L-alanine reduced the activity of the molecule at least 10-fold, indicating stereoselectivity. These results define for the first time the crucial patterns required for the immune recognition of LTA.
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Affiliation(s)
- Susanne Deininger
- Biochemical Pharmacology and Department of Chemistry, University of Konstanz, Konstanz, Germany
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34
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35
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Affiliation(s)
- Andreas Stadelmaier
- Fachbereich Chemie, Universität Konstanz, Fach M 725, 78457 Konstanz, Germany
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36
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Abstract
The innate immune system recognizes pathogen-associated molecular patterns (PAMP) to cope with evolving infections. Toll-like receptors (TLRs) play a pivotal role in recognition of PAMPs. In the course of infection not a single but rather a full panel of different microbial components interacts with distinct TLRs simultaneously. Only limited information is available on effects of combinations of TLR agonists. Here, we have analyzed the effects of lipoteichoic acid (LTA), CpG-DNA and combinations thereof on innate immune cells in vitro. Although proinflammatory cytokines like TNF-alpha were induced by these agonists in quite similar amounts, CpG DNA was superior in its potency to induce IL-12p40 reflecting important differences in the biological valence of LTA and CpG-DNA. When given in combination, LTA and CpG-DNA were additive in induction of TNF-alpha, IL-6 and nitric oxide in RAW 264 macrophages, peritoneal macrophages and dendritic cells. Additive effects were also observed in regard to TNF-alpha mRNA. In contrast, LTA suppressed IL12p40 secretion induced by CpG-DNA in RAW cells and peritoneal macrophages but not in dendritic cells. Intracellular signal cascades (NFkappaB and p38 MAP kinase) showed additive effects after simultaneous triggering. mRNA expression ofTLRs showed only minor regulation after CpG or LTA application and thus does not account for the additive/suppressive effects observed. These results indicate that the consequences of interaction of innate immune cells with microbial pattern depend on the responding cell type and might be differential for certain effector mechanisms. Thus, the pathogen-characteristic panel of TLR ligands will induce pathogen-specific innate responses decisive for the inflammatory reactions.
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Affiliation(s)
- Alexander H Dalpke
- Institute of Medical Microbiology and Hygiene, Philipps-University, Marburg, Germany
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37
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Abstract
We recently purified lipoteichoic acid (LTA) from Staphylococcus aureus to more than 99% purity by a novel preparation method and deduced its structure with the first nuclear magnetic resonance (NMR) of a complete LTA. In contrast to Gram-negative lipopolysaccharides, this LTA requires the toll-like receptor (TLR)-2 and not TLR-4 for cytokine induction in monocytes and macrophages. To elucidate the structure-function relationships for LTA from S. aureus, the lipid anchor was prepared by either acidic hydrolysis of native LTA or chemical synthesis (gentiobiosyl-sn-dimyristoylglycerol). Next, a complete LTA molecule with six glycerophosphate units carrying four alanine plus one N-acetyl-glucosamine substituent was synthesized, which displayed the same potency to activate monocytes as native LTA. However, 100-1,000 times higher concentrations of the lipid anchor were required for cytokine induction. It is worthy to note that replacing D-alanine with L-alanine blunted the effect indicating stereoselective recognition. The structure identification of this synthesized and biologically active LTA was proven by NMR and matrix-assisted laser desorption-ionization mass spectrometry. We concluded that the lipid anchor, with its fatty acids, represents an integral part of the immunostimulatory activity of LTA, but requires additional structural components on the polyglycerophosphate backbone.
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38
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Ellingsen E, Morath S, Flo T, Schromm A, Hartung T, Thiemermann C, Espevik T, Golenbock D, Foster D, Solberg R, Aasen A, Wang J. Induction of cytokine production in human T cells and monocytes by highly purified lipoteichoic acid: involvement of Toll-like receptors and CD14. Med Sci Monit 2002; 8:BR149-56. [PMID: 12011760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
BACKGROUND The pro-inflammatory potential of lipoteichoic acid (LTA) from Staphylococcus aureus is controversial. The present study was undertaken to examine the ability of highly purified and characterized S. aureus LTA to stimulate the production of pro-inflammatory cytokines in human leukocytes at both mRNA and protein level, and to study the involvement of Toll-like receptors (TLRs) and CD14 in this response. MATERIAL/METHODS Purified LTA was administered to whole human blood ex-vivo (or primary adherent monocytes) and the cytokine response assessed in plasma by EIA. Cytokine mRNA was measured by RT-PCR on leukocyte subsets isolated following stimulation. To study the involvement of specific receptors for LTA signaling, CHO cells transfected with CD14 and/or TLR2, TLR4 were used, as well as antibodies directed against these receptors. RESULTS Addition of highly purified LTA to human whole blood or primary adherent human monocytes elicited a time and concentration dependent release of tumor necrosis factor alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), IL-6 and IL-8. Messenger RNA encoding TNF-alpha, IL-1 beta and IL-6 seemed to be accumulated in monocytes and T cells, but not in granulocytes and B cells. Expression of TLR2, but not TLR4, in chinese hamster ovary cells conferred responsiveness to LTA. However, antibodies directed towards TLR2 (clone TL2.1) or TLR4 (clone HTA125) failed to inhibit TNF-a release induced by LTA in both the whole blood model and in adherent monocytes. In contrast, blockade of the CD14 receptor with MAb18D11 strongly attenuated the LTA induced release of TNF-alpha in both models. CONCLUSIONS We propose that (i) LTA from S. aureus triggers the release of cytokines during staphylococcal infections, and (ii) both monocytes and T cells contribute to cytokine production induced by LTA. TLR2 may mediate cellular activation by LTA, but the functional significance of this receptor during staphylococcal infections remains elusive.
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Affiliation(s)
- Espen Ellingsen
- Institute for Surgical Research, Rikshospitalet - National Hospital, N-0027 Oslo, Norway
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39
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Kanz KG, Morath S, Lackner CK, Mutschler W. [Personal safety of rescue workers has the highest priority. Acute management of electric accidents]. MMW Fortschr Med 2002; 144:43-6. [PMID: 12014278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Affiliation(s)
- K G Kanz
- Chirurg. Klinik und Poliklinik-Innenstadt, Klinikum, Ludwig-Maximilians-Universität München.
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40
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Hermann C, Spreitzer I, Schröder NWJ, Morath S, Lehner MD, Fischer W, Schütt C, Schumann RR, Hartung T. Cytokine induction by purified lipoteichoic acids from various bacterial species--role of LBP, sCD14, CD14 and failure to induce IL-12 and subsequent IFN-gamma release. Eur J Immunol 2002; 32:541-51. [PMID: 11828371 DOI: 10.1002/1521-4141(200202)32:2<541::aid-immu541>3.0.co;2-p] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We have recently shown that highly purified lipoteichoic acid (LTA) represents a major immunostimulatory principle of Staphylococcus aureus. In order to test whether this translates to other bacterial species, we extracted and purified LTA from 12 laboratory-grown species. All LTA induced the release of TNF-alpha, IL-1beta, IL-6 and IL-10 in human whole blood. Soluble CD14 (sCD14) inhibited monokine induction by LTA but failed to confer LTA responsiveness for IL-6 and IL-8 release of human umbilical vein endothelial cells (HUVEC). In a competitive LPS-binding protein (LBP) binding assay, the IC(50) of the tested LTA preparations was up to 3,230-fold higher than for LPS. LBP enhanced TNF-alpha release of human peripheral blood mononuclear cells (PBMC) upon LPS but not LTA stimulation. These data demonstrate a differential role for the serum proteins LBP and sCD14 in the recognition of LPS and LTA. Different efficacies of various anti-CD14 antibodies against LPS vs. LTA-induced cytokine release suggest that the recognition sites of CD14 for LPS and LTA are distinct with a partial overlap. While the maximal achievable monokine release in response to LTA was comparable to LPS, all LTA induced significantly less IL-12 and IFN-gamma. IL-12 substitution increased LTA-inducible IFN-gamma release up to 180-fold, suggesting a critical role of poor LTA-inducible IL-12 for IFN-gamma formation. Pretreatment with IFN-gamma rendered galactosamine-sensitized mice sensitive to challenge with LTA. In conclusion, LTA compared to LPS, are weak inducers of IL-12 and subsequent IFN-gamma formation which might explain their lower toxicity in vivo.
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Affiliation(s)
- Corinna Hermann
- Biochemical Pharmacology, University of Konstanz, D-78457 Konstanz, Germany
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41
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Hermann C, Spreitzer I, Schröder NWJ, Morath S, Lehner MD, Fischer W, Schütt C, Schumann RR, Hartung T. Cytokine induction by purified lipoteichoic acids from various bacterial species - Role of LBP, sCD14, CD14 and failure to induce IL-12 and subsequent IFN-γ release. Eur J Immunol 2002. [DOI: 10.1002/1521-4141(200202)32:2%3c541::aid-immu541%3e3.0.co;2-p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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42
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Abstract
Fractionation of commercial preparations of lipoteichoic acids (LTA) by hydrophobic interaction chromatography (HIC) and nuclear magnetic resonance spectroscopy revealed very inhomogeneous compositions and decomposition of the LTA structure: LTA content of the preparations averaged 61% for Streptococcus pyogenes, 16% for Bacillus subtilis, and 75% for Staphylococcus aureus. The decomposition was characterized by a loss of glycerophosphate units as well as alanine and N-acetylglucosamine substituents. All preparations contained-to varying degrees-non-LTA, non-lipopolysaccharide (LPS) immunostimulatory components as indicated by their elution profile in HIC, lack of phosphate, and negative Limulus amoebocyte lysate (LAL) test results. After purification, the commercial LTA from Bacillus subtilis and S. pyogenes but not LTA from S. aureus induced the release of tumor necrosis factor alpha, interleukin 1 beta (IL-1beta), IL-6, and IL-10 in human blood. While pure LTA are negative in the LAL assay, endotoxin equivalents of more than 10 ng of LPS/mg of LTA were found in the commercial preparations. Taken together, these data indicate that these crude preparations with relatively high endotoxin contamination are not suitable for characterizing the activation of immune cells by LTA.
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Affiliation(s)
- Siegfried Morath
- University of Konstanz, Biochemical Pharmacology, Konstanz, Germany
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43
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Lehner MD, Morath S, Michelsen KS, Schumann RR, Hartung T. Induction of cross-tolerance by lipopolysaccharide and highly purified lipoteichoic acid via different Toll-like receptors independent of paracrine mediators. J Immunol 2001; 166:5161-7. [PMID: 11290799 DOI: 10.4049/jimmunol.166.8.5161] [Citation(s) in RCA: 221] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Exposure of macrophages to LPS induces a state of hyporesponsiveness to subsequent stimulation with LPS termed LPS desensitization or tolerance. To date, it is not known whether similar mechanisms of macrophage refractoriness are induced on contact with components of Gram-positive bacteria. In the present study, we demonstrate that pretreatment with highly purified lipoteichoic acid (LTA) results in suppression of cytokine release on restimulation with LTA in vitro and in vivo in both C3H/HeN and C3H/HeJ mice, but not in macrophages from Toll-like receptor (TLR)-2-deficient mice. Furthermore, desensitization in response to LPS or LTA exposure also inhibits responses to the other stimulus ("cross-tolerance"), suggesting that signaling pathways shared by TLR2 and TLR4 are impaired during tolerance. Finally, we show that LPS- or LTA-induced cross-tolerance is not transferred to hyporesponsive cells cocultured with LPS/LTA-responsive macrophages, showing that soluble mediators do not suffice for tolerance induction in neighboring cells.
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Affiliation(s)
- M D Lehner
- Biochemical Pharmacology, University of Konstanz, Konstanz, Germany
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44
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Abstract
Lipoteichoic acids (LTAs) have been proposed as putative Gram-positive immunostimulatory counterparts to Gram-negative lipopolysaccharides. However, LTA from Staphylococcus aureus, the clinically most frequent Gram-positive pathogen, was inactive after purification. Here, a novel isolation procedure to prepare pure (>99%) biologically active LTA, allowing the first structural analysis by nuclear magnetic resonance and mass spectrometry, is described. A comparison with LTA purified by standard techniques revealed that alanine substituents are lost during standard purification, resulting in attenuated cytokine induction activity. In line with this finding, hydrolysis of alanine substituents of active LTA decimated cytokine induction. LTA represents a major immunostimulatory component of S. aureus.
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Affiliation(s)
- Siegfried Morath
- Department of Biochemical Pharmacology, University of Konstanz, D-78457 Konstanz, Germany
| | - Armin Geyer
- Department of Chemistry, University of Konstanz, D-78457 Konstanz, Germany
| | - Thomas Hartung
- Department of Biochemical Pharmacology, University of Konstanz, D-78457 Konstanz, Germany
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