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Andresen E, Günther G, Bullwinkel J, Lange C, Heine H. Increased expression of beta-defensin 1 (DEFB1) in chronic obstructive pulmonary disease. PLoS One 2011; 6:e21898. [PMID: 21818276 PMCID: PMC3139569 DOI: 10.1371/journal.pone.0021898] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/08/2011] [Indexed: 12/21/2022] Open
Abstract
On-going airway inflammation is characteristic for the pathophysiology of chronic obstructive pulmonary disease (COPD). However, the key factors determining the decrease in lung function, an important clinical parameter of COPD, are not clear. Genome-wide linkage analyses provide evidence for significant linkage to airway obstruction susceptibility loci on chromosome 8p23, the location of the human defensin gene cluster. Moreover, a genetic variation in the defensin beta 1 (DEFB1) gene was found to be associated with COPD. Therefore, we hypothesized that DEFB1 is differently regulated and expressed in human lungs during COPD progression. Gene expression of DEFB1 was assessed in bronchial epithelium and BAL fluid cells of healthy controls and patients with COPD and using bisulfite sequencing and ChIP analysis, the epigenetic control of DEFB1 mRNA expression was investigated. We can demonstrate that DEFB1 mRNA expression was significantly increased in bronchopulmonary specimen of patients with COPD (n = 34) vs. healthy controls (n = 10) (p<0.0001). Furthermore, a significant correlation could be detected between DEFB1 and functional parameters such as FEV1 (p = 0.0024) and the FEV1/VC ratio (p = 0.0005). Upregulation of DEFB1 mRNA was paralleled by changes in HDAC1-3, HDAC5 and HDAC8 mRNA expression. Whereas bisulfite sequencing revealed no differences in the methylation state of DEFB1 promoter between patients with COPD and controls, ChIP analysis showed that enhanced DEFB1 mRNA expression was associated with the establishment of an active histone code. Thus, expression of human DEFB1 is upregulated and related to the decrease in pulmonary function in patients with COPD.
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Watson J, Selleck P, Axell A, Bruce K, Taylor T, Heine H, Daniels P, Jeggo M. Diagnosis of equine influenza virus infections in quarantine stations in Australia, 2007. Aust Vet J 2011; 89 Suppl 1:4-6. [DOI: 10.1111/j.1751-0813.2011.00722.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Fischer K, Stein K, Ulmer AJ, Lindner B, Heine H, Holst O. Cytokine-inducing lipoteichoic acids of the allergy-protective bacterium Lactococcus lactis G121 do not activate via Toll-like receptor 2. Glycobiology 2011; 21:1588-95. [DOI: 10.1093/glycob/cwr071] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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54
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Gisch N, Buske B, Heine H, Lindner B, Zähringer U. Synthesis of biotinylated muramyl tripeptides with NOD2-stimulating activity. Bioorg Med Chem Lett 2011; 21:3362-6. [DOI: 10.1016/j.bmcl.2011.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Revised: 03/30/2011] [Accepted: 04/03/2011] [Indexed: 10/18/2022]
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Heine H. TLRs, NLRs and RLRs: innate sensors and their impact on allergic diseases--a current view. Immunol Lett 2011; 139:14-24. [PMID: 21554901 DOI: 10.1016/j.imlet.2011.04.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 04/19/2011] [Accepted: 04/20/2011] [Indexed: 12/25/2022]
Abstract
Charles Janeway first wrote 1989 about how important recognition of "certain characteristics or patterns common on infectious agents but absent from the host" would be for our immune response [1]. Surprisingly, it almost took 10 years before his ideas would lead to the revolutionary findings that fundamentally changed the view of the innate immune system over the past decade. Recognition of invading microorganisms belongs to the primary tasks of the innate immune system and is achieved through different families of innate immune sensors. Among these, Toll-like receptors (TLRs), nucleotide-binding domain and leucine-rich repeat containing receptors (NLRs) and Rig-I-like receptors (RLRs) have drawn major interests over the last decade. These receptor families are targeted by overlapping classes of pathogens and share functional domains and signal transduction pathways (see Fig. 1 and Table 1 for an overview of their structural organization, ligands, adaptors and activated pathways). This current view describes our present knowledge about these three main innate immune receptor families and their importance for adaptive immune responses such as asthma and allergy.
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Andresen E, Lange C, Strodthoff D, Goldmann T, Fischer N, Sahly H, Branscheid D, Heine H. S100A7/psoriasin expression in the human lung: unchanged in patients with COPD, but upregulated upon positive S. aureus detection. BMC Pulm Med 2011; 11:10. [PMID: 21324122 PMCID: PMC3050873 DOI: 10.1186/1471-2466-11-10] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 02/15/2011] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Progressive airway inflammation and susceptibility to the airway colonisation and infection are characteristic for the pathophysiology of chronic obstructive pulmonary disease (COPD). Antimicrobial peptides (AMPs) are central to the function of the innate host immune response against microbial pathogens and are regulators of inflammation and immunity. S100A7/psoriasin, a recently described AMP, is an essential component of the human epithelia against invading pathogens and acts as an effector molecule of the host innate defence in the skin. We hypothesized that S100A7/psoriasin is involved in the airway mucosal immunity and differently regulated and expressed in the lung during progression of COPD. METHODS S100A7/psoriasin gene expression was assessed in bronchial biopsies and bronchoalveolar lavage (BAL) fluid cells of healthy controls and COPD patients. Using confocal microscopy and immunohistochemistry, the protein expression of S100A7/psoriasin was investigated. RESULTS Here, we report that S100A7/psoriasin, the major antimicrobial peptide of the human skin, is constitutively expressed in perinuclear granules of human bronchial epithelial cells and alveolar macrophages. Whereas typical activators of the innate immune response like TLR ligands and cytokines induced the upregulation of CXCL-8 mRNA and release of CXCL-8 by epithelial cells, S100A7/psoriasin mRNA expression was not modulated. To investigate a potential association of S100A7/psoriasin with COPD, S100A7/psoriasin mRNA expression was assessed in bronchial biopsies and BAL fluid cells of patients at different stages of COPD and controls. Overall, 10 healthy individuals and 34 COPD patients were enrolled in this study. We found an association of S100A7/psoriasin mRNA expression with bacterial detection in the tracheobronchial system (p = 0.0304), which was the strongest in individuals positive for with S. aureus (p = 0.0005). However, S100A7/psoriasin mRNA expression was not altered during the progression of COPD. CONCLUSIONS S100A7/psoriasin gene expression is unchanged in the airways during COPD. The newly identified association of S100A7/psoriasin with S. aureus may provide new insights into the antimicrobial defence response of the human airways, leading to the induction of S100A7/psoriasin upon microbial challenge.
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Debarry J, Hanuszkiewicz A, Stein K, Holst O, Heine H. The allergy-protective properties of Acinetobacter lwoffii F78 are imparted by its lipopolysaccharide. Allergy 2010; 65:690-7. [PMID: 19909295 DOI: 10.1111/j.1398-9995.2009.02253.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
BACKGROUND An increasing number of epidemiological studies show that exposure to farming environment during early childhood strongly influences the development of allergic reactions later in life ('hygiene hypothesis'). Also, it had been shown that certain bacteria from this environment may have allergy-protective properties. In the present study, we further characterized one of these bacteria, namely Acinetobacter lwoffii F78, with regard to the bacteria-induced signaling and possible mechanisms of allergy protection. METHODS The impact of A. lwoffii F78 on human monocyte-derived dendritic cells especially with respect to their T(Helper) cell polarization capacity was investigated by ELISA and real-time PCR experiments as well as confocal microscopy. The responsible molecule for these effects was further characterized and identified using blocking experiments. RESULTS It was shown that A. lwoffii F78 induced a T(H)1-polarizing program in human dendritic cells which led to T(H)1 differentiation. In addition, a positive influence on the TBet/GATA3 level could be detected. Blocking experiments revealed that the lipopolysaccharide (LPS) of A. lwoffii F78 was the responsible molecule promoting these effects. CONCLUSION We found evidence that the allergy-protecting effects of A. lwoffii F78 are because of the activation of a T(H)1-polarizing program in human dendritic cells, and that the LPS of A. lwoffii F78 is responsible for these beneficial effects.
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Voynov V, Chennamsetty N, Kayser V, Helk B, Forrer K, Zhang H, Fritsch C, Heine H, Trout BL. Dynamic fluctuations of protein-carbohydrate interactions promote protein aggregation. PLoS One 2009; 4:e8425. [PMID: 20037630 PMCID: PMC2791859 DOI: 10.1371/journal.pone.0008425] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Accepted: 11/30/2009] [Indexed: 11/18/2022] Open
Abstract
Protein-carbohydrate interactions are important for glycoprotein structure and function. Antibodies of the IgG class, with increasing significance as therapeutics, are glycosylated at a conserved site in the constant Fc region. We hypothesized that disruption of protein-carbohydrate interactions in the glycosylated domain of antibodies leads to the exposure of aggregation-prone motifs. Aggregation is one of the main problems in protein-based therapeutics because of immunogenicity concerns and decreased efficacy. To explore the significance of intramolecular interactions between aromatic amino acids and carbohydrates in the IgG glycosylated domain, we utilized computer simulations, fluorescence analysis, and site-directed mutagenesis. We find that the surface exposure of one aromatic amino acid increases due to dynamic fluctuations. Moreover, protein-carbohydrate interactions decrease upon stress, while protein-protein and carbohydrate-carbohydrate interactions increase. Substitution of the carbohydrate-interacting aromatic amino acids with non-aromatic residues leads to a significantly lower stability than wild type, and to compromised binding to Fc receptors. Our results support a mechanism for antibody aggregation via decreased protein-carbohydrate interactions, leading to the exposure of aggregation-prone regions, and to aggregation.
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Ernst H, Heine H. Schilddrüsenkarzinom: Szintigraphischer Nachweis von Fernmetastasen bei negativem Röntgenbefund. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1226810] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Heinemann L, Heine H, Assmann A, Schädlich H, Barth W, Thiel C, Martin I, Eisenblätter D, Braun H, Johnsen D. Risk factors in the population of the GDR-MONICA Study (1983/84). ACTA MEDICA SCANDINAVICA. SUPPLEMENTUM 2009; 728:144-9. [PMID: 3202023 DOI: 10.1111/j.0954-6820.1988.tb05566.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The GDR-MONICA project comprises 25 administratively defined areas with a population of nearly two million people aged 25-64. Data from the first random sample survey are reported here. The survey gathered information regarding risk factors, dietary behaviour, physical activity and psychosocial factors from 11,281 persons aged 25-64. The average risk factor levels were high in the population: The mean casual blood pressure was 140/88 mmHg and 138/86 mmHg for men and women respectively. In both sexes the mean total cholesterol level exceeded 6.1 mmol/L, and the mean body mass index (BMI) was just over 26.0. The study population consumed, on average, excessive amounts of energy, fat, alcohol, and sodium, and too few carbohydrates. Preliminary conclusions regarding unfavourable trends in risk factor levels have been drawn by comparing the present data with other recent reliable epidemiological studies.
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Günther G, Andresen E, Bullwinkel J, Lange C, Heine H. Antimicrobial peptides in COPD. Pneumologie 2009. [DOI: 10.1055/s-0029-1214054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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62
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Andresen E, Bullwinkel J, Lange C, Heine H. Molecular basis of increased Defensin Beta-1 gene expression in the lung of COPD patients. Pneumologie 2009. [DOI: 10.1055/s-0029-1214059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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63
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Haase H, Ober-Blöbaum JL, Engelhardt G, Hebel S, Heit A, Heine H, Rink L. Zinc signals are essential for lipopolysaccharide-induced signal transduction in monocytes. THE JOURNAL OF IMMUNOLOGY 2009; 181:6491-502. [PMID: 18941240 DOI: 10.4049/jimmunol.181.9.6491] [Citation(s) in RCA: 208] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Cytosolic alterations of calcium ion concentrations are an integral part of signal transduction. Similar functions have been hypothesized for other metal ions, in particular zinc (Zn(2+)), but this still awaits experimental verification. Zn(2+) is important for multiple cellular functions, especially in the immune system. Among other effects, it influences formation and secretion of pro-inflammatory cytokines, including TNF-alpha. Here we demonstrate that these effects are due to a physiological signaling system involving intracellular Zn(2+) signals. An increase of the intracellular zinc ion concentration occurs upon stimulation of human leukocytes with Escherichia coli, LPS, Pam(3)CSK(4), TNF-alpha, or insulin, predominantly in monocytes. Chelating this zinc signal with the membrane permeable zinc-specific chelator TPEN (N,N,N',N'-tetrakis-(2-pyridyl-methyl)ethylenediamine) completely blocks activation of LPS-induced signaling pathways involving p38 MAPK, ERK1/2, and NF-kappaB, and abrogates the release of proinflammatory cytokines, including TNF-alpha. This function of Zn(2+) is not limited to monocytes or even the immune system, but seems to be another generalized signaling system based on intracellular fluctuations of metal ion concentrations, acting parallel to Ca(2+).
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Riekenberg S, Farhat K, Debarry J, Heine H, Jung G, Wiesmüller KH, Ulmer AJ. Regulators of G-protein signalling are modulated by bacterial lipopeptides and lipopolysaccharide. FEBS J 2008; 276:649-59. [PMID: 19120454 DOI: 10.1111/j.1742-4658.2008.06813.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Regulators of G-protein signalling accelerate the GTPase activity of G(alpha) subunits, driving G proteins in their inactive GDP-bound form. This property defines them as GTPase activating proteins. Here the effect of different Toll-like receptor agonists on RGS1 and RGS2 expression in murine bone marrow-derived macrophages and J774 cells was analysed. After stimulation with TLR2/1 or TLR2/6 lipopeptide ligands and the TLR4/MD2 ligand lipopolysaccharide, microarray analyses show only modulation of RGS1 and RGS2 among all the regulators of G-protein signalling tested. Real-time PCR confirmed modulation of RGS1 and RGS2. In contrast to RGS2, which was always downregulated, RGS1 mRNA was upregulated during the first 30 min after stimulation, followed by downregulation. Similar results were also found in the murine macrophage cell line J774. The ligand for intracellular TLR9 modulates RGS1 and RGS2 in a similar manner. However, the TLR3 ligand poly(I:C) permanently upregulates RGS1 and RGS2 expression indicating a different modulation by the MyD88- and TRIF-signalling pathway. This was confirmed using MyD88(-/-) and TRIF(-/-) bone marrow-derived macrophages. Modulation of RGS1 and RGS2 by Toll-like receptor ligands plays an important role during inflammatory and immunological reactions after bacterial and viral infection.
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Hanuszkiewicz A, Kaczyński Z, Lindner B, Goldmann T, Vollmer E, Debarry J, Heine H, Holst O. Structural Analysis of the Capsular Polysaccharide fromAcinetobacter lwoffiiF78. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800887] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Hanuszkiewicz A, Hübner G, Vinogradov E, Lindner B, Brade L, Brade H, Debarry J, Heine H, Holst O. Structural and Immunochemical Analysis of the Lipopolysaccharide fromAcinetobacter lwoffii F78 Located OutsideChlamydiaceaewith aChlamydia-Specific Lipopolysaccharide Epitope. Chemistry 2008; 14:10251-8. [DOI: 10.1002/chem.200800958] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Heine H, Schmidt H, Anders G. Klinisches Bild und Therapieresultate bei Patienten mit Endangitis obliterans und peripherer Arteriosklerose. J Vasc Res 2008. [DOI: 10.1159/000157619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Vogel K, Blümer N, Korthals M, Mittelstädt J, Garn H, Ege M, von Mutius E, Gatermann S, Bufe A, Goldmann T, Schwaiger K, Renz H, Brandau S, Bauer J, Heine H, Holst O. Animal shed Bacillus licheniformis spores possess allergy-protective as well as inflammatory properties. J Allergy Clin Immunol 2008; 122:307-12, 312.e1-8. [PMID: 18582924 DOI: 10.1016/j.jaci.2008.05.016] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Revised: 04/09/2008] [Accepted: 05/14/2008] [Indexed: 12/17/2022]
Abstract
BACKGROUND Numerous epidemiologic studies have demonstrated an allergy-protective effect of farm life early in childhood. It has been hypothesized that environmental exposure to microbes may contribute to this effect. Because of their small size and thereby their potential for deposition in lower airways of small children, bacterial spores may be candidates for such allergy-protective effects. OBJECTIVE To investigate immune responses elicited by exposure to Bacillus spores in experimental settings. METHODS Animal shed and mattress dusts were analyzed for bacteria and fungi by aerobic and anaerobic growth. Bacillus licheniformis, the most prominent microorganism found in these samples, was investigated with respect to spore specific stimulation of pattern recognition receptors, monocyte-derived dendritic cells and T(H)-cell polarization in vitro as well as to the prevention of asthma development in a mouse model of allergic asthma. RESULTS In vitro, B. licheniformis spores activated a T(H)1 cytokine expression profile. In vivo application of these spores resulted in less spore-specific but long-lasting immune activation preventing eosinophilia and goblet cell hyperplasia; however, they provoked an influx of neutrophils in lung tissue of asthmatic mice. CONCLUSION Bacterial spores may contribute to the allergy-protective properties of farming environments, but their persistence in the lung causes ongoing immune activation in mouse experiments.
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Andresen E, Bullwinkel J, Lange C, Heine H. Epigenetic regulation of defensin gene expression in lung epithelial cells and COPD. Pneumologie 2008. [DOI: 10.1055/s-2008-1074128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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70
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Zähringer U, Lindner B, Inamura S, Heine H, Alexander C. TLR2 - promiscuous or specific? A critical re-evaluation of a receptor expressing apparent broad specificity. Immunobiology 2008; 213:205-24. [PMID: 18406368 DOI: 10.1016/j.imbio.2008.02.005] [Citation(s) in RCA: 302] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2007] [Revised: 02/28/2008] [Accepted: 02/28/2008] [Indexed: 11/19/2022]
Abstract
Of all pattern recognition receptors (PRR) in innate immunity, Toll-like receptor 2 (TLR2) recognizes the structurally broadest range of different bacterial compounds known as pathogen-associated molecular patterns (PAMPs). TLR2 agonists identified so far are lipopolysaccharides (LPSs) from different bacterial strains, lipoproteins, (synthetic) lipopeptides, lipoarabinomannans, lipomannans, glycosylphosphatidylinositol, lipoteichoic acids (LTA), various proteins including lipoproteins and glycoproteins, zymosan, and peptidoglycan (PG). Because these molecules are structurally diverse, it seems unlikely that TLR2 has the capability to react with all agonists to the same degree. The aim of this review is to identify and describe well-defined structure-function relationships for TLR2. Because of its biomedical importance and because its genetics and biochemistry are presently most completely known among all Gram-positive bacteria, we have chosen Staphylococcus aureus as a focus. Our data together with those reported by other groups reveal that only lipoproteins/lipopeptides are sensed at physiologically concentrations by TLR2 at picomolar levels. This finding implies that the activity of all other putative bacterial compounds so far reported as TLR2 agonists was most likely due to contaminating highly active natural lipoproteins and/or lipopeptides.
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Walter S, Letiembre M, Liu Y, Heine H, Penke B, Hao W, Bode B, Manietta N, Walter J, Schulz-Schuffer W, Fassbender K. Role of the toll-like receptor 4 in neuroinflammation in Alzheimer's disease. Cell Physiol Biochem 2007; 20:947-56. [PMID: 17982277 DOI: 10.1159/000110455] [Citation(s) in RCA: 388] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2007] [Indexed: 11/19/2022] Open
Abstract
Microglial activation is a key feature in Alzheimer's disease and is considered to contribute to progressive neuronal injury by release of neurotoxic products. The innate immune receptor Toll-like-receptor 4 (TLR4), localized on the surface of microglia, is a first-line host defense receptor against invading microorganisms. Here, we show that a spontaneous loss-of-function mutation in the Tlr4 gene strongly inhibits microglial and monocytic activation by aggregated Alzheimer amyloid peptide resulting in a significantly lower release of the inflammatory products IL-6, TNFalpha and nitric oxide. Treatment of primary murine neuronal cells with supernatant of amyloid peptide-stimulated microglia demonstrates that Tlr4 contributes to amyloid peptide-induced microglial neurotoxicity. In addition, stimulation experiments in transfected HEK293 cells allowed to define a tri-molecular receptor complex consisting of TLR4, MD-2 and CD14 necessary for full cellular activation by aggregated amyloid peptide. A clinical relevance of these findings is supported by a marked upregulation of Tlr4 mRNA in APP transgenic mice and by an increased expression of TLR4 in Alzheimer's disease brain tissue associated with amyloid plaque deposition. Together, these observations provide the first evidence for a role of the key innate immune receptor, TLR4, in neuroinflammation in Alzheimer's disease.
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Farhat K, Riekenberg S, Heine H, Debarry J, Lang R, Mages J, Buwitt-Beckmann U, Röschmann K, Jung G, Wiesmüller KH, Ulmer AJ. Heterodimerization of TLR2 with TLR1 or TLR6 expands the ligand spectrum but does not lead to differential signaling. J Leukoc Biol 2007; 83:692-701. [DOI: 10.1189/jlb.0807586] [Citation(s) in RCA: 223] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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von Bülow V, Dubben S, Engelhardt G, Hebel S, Plümäkers B, Heine H, Rink L, Haase H. Zinc-dependent suppression of TNF-alpha production is mediated by protein kinase A-induced inhibition of Raf-1, I kappa B kinase beta, and NF-kappa B. THE JOURNAL OF IMMUNOLOGY 2007; 179:4180-6. [PMID: 17785857 DOI: 10.4049/jimmunol.179.6.4180] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Excessive and permanent cytokine production in response to bacterial LPS causes cell and tissue damage, and hence organ failure during sepsis. We have previously demonstrated that zinc treatment prevents LPS-induced TNF-alpha expression and production in human monocytes by inhibiting cyclic nucleotide phosphodiesterase (PDE) activity and expression, and subsequent elevation of the cyclic nucleotide cGMP. In the present study, we investigated the molecular mechanism by which cGMP signaling affects the LPS-induced signaling cascade to suppress TNF-alpha transcription and release from monocytes. Zinc-mediated cGMP elevation led to cross activation of protein kinase A. This zinc-induced protein kinase A activation inhibited Raf-1 activity by phosphorylation at serine 259, preventing activation of Raf-1 by phosphorylation of serine 338. By this mechanism, zinc suppressed LPS-induced activation of IkappaB kinase beta (IKKbeta) and NF-kappaB, and subsequent TNF-alpha production. Our study shows that PDE inhibition by zinc modulates the monocytic immune response by selectively intervening in the Raf-1/IKKbeta/NF-kappaB pathway, which may constitute a common mechanism for the anti-inflammatory action of PDE inhibitors.
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Pallister J, Gould A, Harrison D, Hyatt A, Jancovich J, Heine H. Development of real-time PCR assays for the detection and differentiation of Australian and European ranaviruses. JOURNAL OF FISH DISEASES 2007; 30:427-38. [PMID: 17584440 DOI: 10.1111/j.1365-2761.2007.00828.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Serious systemic disease in fish and amphibians is associated with the ranaviruses, epizootic haematopoietic necrosis virus (EHNV) and Bohle iridovirus (BIV) in Australia, and European sheatfish virus (ESV) and European catfish virus (ECV) in Europe. EHNV, ESV and ECV are recognized causative agents of the OIE (Office International des Epizooties) notifiable systemic necrotizing iridovirus syndrome and are currently identified by protein-based assays, none of which are able to rapidly identify the specific agents. The aim of this study was to develop TaqMan real-time PCR assays that differentiated these viruses using nucleotide sequence variation in two ranavirus genes. A conserved probe representing 100% sequence homology was used as a reference for virus-specific probes. The virus-specific probes produced a similar signal level to the conserved probe while those probes binding to non-target viral DNA produced an altered fluorescent curve. The pattern of probe binding was characteristic for each virus. Sensitivity, specificity and dynamic range of the assay were assessed. The test is currently useful as a research and initial screening tool, with the potential to become a sensitive and specific method for detection and differentiation of ranaviruses with further development.
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Debarry J, Garn H, Hanuszkiewicz A, Dickgreber N, Blümer N, von Mutius E, Bufe A, Gatermann S, Renz H, Holst O, Heine H. Acinetobacter lwoffii and Lactococcus lactis strains isolated from farm cowsheds possess strong allergy-protective properties. J Allergy Clin Immunol 2007; 119:1514-21. [PMID: 17481709 DOI: 10.1016/j.jaci.2007.03.023] [Citation(s) in RCA: 193] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Revised: 03/20/2007] [Accepted: 03/22/2007] [Indexed: 02/02/2023]
Abstract
BACKGROUND Children who grow up in a farming environment show lower levels of atopic sensitization, hay fever, and asthma than children of the same age not living in such an environment. A number of investigations provided good evidence that this is due to an early-life contact with cowsheds, farm animals, and/or consumption of products like raw milk. Also, it had been indicated that microorganisms might have an important effect on the development of allergies, and thus the question arose of which farm microbial organisms, their products, or both might induce or influence allergy-protective mechanisms. OBJECTIVE We sought to gain further insight into the potential allergy-protective properties of microbes isolated from the farming environment. METHODS Of a number of bacterial species identified in cowsheds of farms, 2 were selected, isolated, and characterized, namely Acinetobacter lwoffii F78 and Lactococcus lactis G121. The isolates were investigated with regard to their activation of pattern-recognition receptors, the maturation of human monocyte-derived dendritic cells, the upregulation of inflammatory cytokines, the T(H)1-polarizing Notch ligand expression, and their influence on the allergic phenotype. RESULTS It is shown that both bacterial isolates were able to reduce allergic reactions in mice, to activate mammalian cells in vitro, and to induce a T(H)1-polarizing program in dendritic cells. CONCLUSION Our data strongly support the hygiene hypothesis, which states that an environment rich in microbiologic structures, such as a farming environment, might protect against the development of allergies. CLINICAL IMPLICATIONS This work provides the first data on a potential application of cowshed bacteria in allergy protection.
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