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Vinţeler N, Feurdean CN, Petkes R, Barabas R, Boşca BA, Muntean A, Feștilă D, Ilea A. Biomaterials Functionalized with Inflammasome Inhibitors-Premises and Perspectives. J Funct Biomater 2024; 15:32. [PMID: 38391885 PMCID: PMC10889089 DOI: 10.3390/jfb15020032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 01/21/2024] [Accepted: 01/25/2024] [Indexed: 02/24/2024] Open
Abstract
This review aimed at searching literature for data regarding the inflammasomes' involvement in the pathogenesis of oral diseases (mainly periodontitis) and general pathologies, including approaches to control inflammasome-related pathogenic mechanisms. The inflammasomes are part of the innate immune response that activates inflammatory caspases by canonical and noncanonical pathways, to control the activity of Gasdermin D. Once an inflammasome is activated, pro-inflammatory cytokines, such as interleukins, are released. Thus, inflammasomes are involved in inflammatory, autoimmune and autoinflammatory diseases. The review also investigated novel therapies based on the use of phytochemicals and pharmaceutical substances for inhibiting inflammasome activity. Pharmaceutical substances can control the inflammasomes by three mechanisms: inhibiting the intracellular signaling pathways (Allopurinol and SS-31), blocking inflammasome components (VX-765, Emricasan and VX-740), and inhibiting cytokines mediated by the inflammasomes (Canakinumab, Anakinra and Rilonacept). Moreover, phytochemicals inhibit the inflammasomes by neutralizing reactive oxygen species. Biomaterials functionalized by the adsorption of therapeutic agents onto different nanomaterials could represent future research directions to facilitate multimodal and sequential treatment in oral pathologies.
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Affiliation(s)
- Norina Vinţeler
- Department of Oral Rehabilitation, Faculty of Dentistry, "Iuliu Hațieganu" University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
| | - Claudia Nicoleta Feurdean
- Department of Oral Rehabilitation, Faculty of Dentistry, "Iuliu Hațieganu" University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
| | - Regina Petkes
- Department of Chemistry and Chemical Engineering of Hungarian Line of Study, Faculty of Chemistry and Chemical Engineering, Babeș-Bolyai University, 400028 Cluj-Napoca, Romania
| | - Reka Barabas
- Department of Chemistry and Chemical Engineering of Hungarian Line of Study, Faculty of Chemistry and Chemical Engineering, Babeș-Bolyai University, 400028 Cluj-Napoca, Romania
| | - Bianca Adina Boşca
- Department of Histology, Faculty of Medicine, "Iuliu Hațieganu" University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
| | - Alexandrina Muntean
- Department of Paediatric, Faculty of Dentistry, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca 400012, Romania
| | - Dana Feștilă
- Department of Orthodontics, Faculty of Dentistry, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca 400012, Romania
| | - Aranka Ilea
- Department of Oral Rehabilitation, Faculty of Dentistry, "Iuliu Hațieganu" University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
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2
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Díaz-Alvarez L, Martínez-Sánchez ME, Gray E, Pérez-Figueroa E, Ortega E. Aminopeptidase N/CD13 Crosslinking Promotes the Activation and Membrane Expression of Integrin CD11b/CD18. Biomolecules 2023; 13:1488. [PMID: 37892170 PMCID: PMC10604325 DOI: 10.3390/biom13101488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
The β2 integrin CD11b/CD18, also known as complement receptor 3 (CR3), and the moonlighting protein aminopeptidase N (CD13), are two myeloid immune receptors with overlapping activities: adhesion, migration, phagocytosis of opsonized particles, and respiratory burst induction. Given their common functions, shared physical location, and the fact that some receptors can activate a selection of integrins, we hypothesized that CD13 could induce CR3 activation through an inside-out signaling mechanism and possibly have an influence on its membrane expression. We revealed that crosslinking CD13 on the surface of human macrophages not only activates CR3 but also influences its membrane expression. Both phenomena are affected by inhibitors of Src, PLCγ, Syk, and actin polymerization. Additionally, after only 10 min at 37 °C, cells with crosslinked CD13 start secreting pro-inflammatory cytokines like interferons type 1 and 2, IL-12p70, and IL-17a. We integrated our data with a bioinformatic analysis to confirm the connection between these receptors and to suggest the signaling cascade linking them. Our findings expand the list of features of CD13 by adding the activation of a different receptor via inside-out signaling. This opens the possibility of studying the joint contribution of CD13 and CR3 in contexts where either receptor has a recognized role, such as the progression of some leukemias.
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Affiliation(s)
- Laura Díaz-Alvarez
- Instituto de Investigaciones Biomédicas, Departamento de Inmunología, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- Posgrado en Ciencias Biológicas, Unidad de Posgrado, Edificio D, 1° Piso, Circuito de Posgrados, Ciudad Universitaria, Mexico City 04510, Mexico
| | | | - Eleanor Gray
- London Centre for Nanotechnology, Department of Physics and Astronomy, University College London, London WC2R 2LS, UK
| | - Erandi Pérez-Figueroa
- Laboratorio de Investigación en Inmunología y Proteómica, Hospital Infantil de México Federico Gómez, Mexico City 06720, Mexico
| | - Enrique Ortega
- Instituto de Investigaciones Biomédicas, Departamento de Inmunología, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
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3
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Colleselli K, Ebeyer-Masotta M, Neuditschko B, Stierschneider A, Pollhammer C, Potocnjak M, Hundsberger H, Herzog F, Wiesner C. Beyond Pattern Recognition: TLR2 Promotes Chemotaxis, Cell Adhesion, and Migration in THP-1 Cells. Cells 2023; 12:1425. [PMID: 37408259 DOI: 10.3390/cells12101425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 07/07/2023] Open
Abstract
The interaction between monocytes and endothelial cells in inflammation is central to chemoattraction, adhesion, and transendothelial migration. Key players, such as selectins and their ligands, integrins, and other adhesion molecules, and their functions in these processes are well studied. Toll-like receptor 2 (TLR2), expressed in monocytes, is critical for sensing invading pathogens and initiating a rapid and effective immune response. However, the extended role of TLR2 in monocyte adhesion and migration has only been partially elucidated. To address this question, we performed several functional cell-based assays using monocyte-like wild type (WT), TLR2 knock-out (KO), and TLR2 knock-in (KI) THP-1 cells. We found that TLR2 promotes the faster and stronger adhesion of monocytes to the endothelium and a more intense endothelial barrier disruption after endothelial activation. In addition, we performed quantitative mass spectrometry, STRING protein analysis, and RT-qPCR, which not only revealed the association of TLR2 with specific integrins but also uncovered novel proteins affected by TLR2. In conclusion, we show that unstimulated TLR2 influences cell adhesion, endothelial barrier disruption, migration, and actin polymerization.
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Affiliation(s)
- Katrin Colleselli
- Department of Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences, 3500 Krems, Austria
| | - Marie Ebeyer-Masotta
- Department for Biomedical Research, University for Continuing Education Krems, 3500 Krems, Austria
| | - Benjamin Neuditschko
- Institute Krems Bioanalytics, IMC University of Applied Sciences, 3500 Krems, Austria
| | - Anna Stierschneider
- Department of Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences, 3500 Krems, Austria
| | - Christopher Pollhammer
- Department of Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences, 3500 Krems, Austria
| | - Mia Potocnjak
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, 80539 Munich, Germany
| | - Harald Hundsberger
- Department of Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences, 3500 Krems, Austria
| | - Franz Herzog
- Institute Krems Bioanalytics, IMC University of Applied Sciences, 3500 Krems, Austria
| | - Christoph Wiesner
- Department of Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences, 3500 Krems, Austria
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4
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Uriarte SM, Hajishengallis G. Neutrophils in the periodontium: Interactions with pathogens and roles in tissue homeostasis and inflammation. Immunol Rev 2023; 314:93-110. [PMID: 36271881 PMCID: PMC10049968 DOI: 10.1111/imr.13152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Neutrophils are of key importance in periodontal health and disease. In their absence or when they are functionally defective, as occurs in certain congenital disorders, affected individuals develop severe forms of periodontitis in early age. These observations imply that the presence of immune-competent neutrophils is essential to homeostasis. However, the presence of supernumerary or hyper-responsive neutrophils, either because of systemic priming or innate immune training, leads to imbalanced host-microbe interactions in the periodontium that culminate in dysbiosis and inflammatory tissue breakdown. These disease-provoking imbalanced interactions are further exacerbated by periodontal pathogens capable of subverting neutrophil responses to their microbial community's benefit and the host's detriment. This review attempts a synthesis of these findings for an integrated view of the neutrophils' ambivalent role in periodontal disease and, moreover, discusses how some of these concepts underpin the development of novel therapeutic approaches to treat periodontal disease.
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Affiliation(s)
- Silvia M. Uriarte
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA
| | - George Hajishengallis
- Department of Basic and Translational Sciences, Laboratory of Innate Immunity and Inflammation, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
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5
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Tomasek K, Leithner A, Glatzova I, Lukesch MS, Guet CC, Sixt M. Type 1 piliated uropathogenic Escherichia coli hijack the host immune response by binding to CD14. eLife 2022; 11:78995. [PMID: 35881547 PMCID: PMC9359703 DOI: 10.7554/elife.78995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 07/19/2022] [Indexed: 11/13/2022] Open
Abstract
A key attribute of persistent or recurring bacterial infections is the ability of the pathogen to evade the host’s immune response. Many Enterobacteriaceae express type 1 pili, a pre-adapted virulence trait, to invade host epithelial cells and establish persistent infections. However, the molecular mechanisms and strategies by which bacteria actively circumvent the immune response of the host remain poorly understood. Here, we identified CD14, the major co-receptor for lipopolysaccharide detection, on mouse dendritic cells (DCs) as a binding partner of FimH, the protein located at the tip of the type 1 pilus of Escherichia coli. The FimH amino acids involved in CD14 binding are highly conserved across pathogenic and non-pathogenic strains. Binding of the pathogenic strain CFT073 to CD14 reduced DC migration by overactivation of integrins and blunted expression of co-stimulatory molecules by overactivating the NFAT (nuclear factor of activated T-cells) pathway, both rate-limiting factors of T cell activation. This response was binary at the single-cell level, but averaged in larger populations exposed to both piliated and non-piliated pathogens, presumably via the exchange of immunomodulatory cytokines. While defining an active molecular mechanism of immune evasion by pathogens, the interaction between FimH and CD14 represents a potential target to interfere with persistent and recurrent infections, such as urinary tract infections or Crohn’s disease.
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Affiliation(s)
- Kathrin Tomasek
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | | | - Ivana Glatzova
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | | | - Calin C Guet
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Michael Sixt
- Institute of Science and Technology Austria, Klosterneuburg, Austria
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6
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Neves GWP, Wong SSW, Aimanianda V, Simenel C, Guijarro JI, Walls C, Willment JA, Gow NAR, Munro CA, Brown GD, Lopes-Bezerra LM. Complement-Mediated Differential Immune Response of Human Macrophages to Sporothrix Species Through Interaction With Their Cell Wall Peptidorhamnomannans. Front Immunol 2021; 12:749074. [PMID: 34867977 PMCID: PMC8636148 DOI: 10.3389/fimmu.2021.749074] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/25/2021] [Indexed: 12/23/2022] Open
Abstract
In this study, the human immune response mechanisms against Sporothrix brasiliensis and Sporothrix schenckii, two causative agents of human and animal sporotrichosis, were investigated. The interaction of S. brasiliensis and S. schenckii with human monocyte-derived macrophages (hMDMs) was shown to be dependent on the thermolabile serum complement protein C3, which facilitated the phagocytosis of Sporothrix yeast cells through opsonization. The peptidorhamnomannan (PRM) component of the cell walls of these two Sporothrix yeasts was found to be one of their surfaces exposed pathogen-associated molecular pattern (PAMP), leading to activation of the complement system and deposition of C3b on the Sporothrix yeast surfaces. PRM also showed direct interaction with CD11b, the specific component of the complement receptor-3 (CR3). Furthermore, the blockade of CR3 specifically impacted the interleukin (IL)-1β secretion by hMDM in response to both S. brasiliensis and S. schenckii, suggesting that the host complement system plays an essential role in the inflammatory immune response against these Sporothrix species. Nevertheless, the structural differences in the PRMs of the two Sporothrix species, as revealed by NMR, were related to the differences observed in the host complement activation pathways. Together, this work reports a new PAMP of the cell surface of pathogenic fungi playing a role through the activation of complement system and via CR3 receptor mediating an inflammatory response to Sporothrix species.
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Affiliation(s)
- Gabriela W. P. Neves
- Cell Biology Department, Rio de Janeiro State University, Rio de Janeiro, Brazil
| | | | | | - Catherine Simenel
- Institut Pasteur, Biological NMR and HDX-MS Technological Platform, CNRS UMR3528, Paris, France
| | - J. Iñaki Guijarro
- Institut Pasteur, Biological NMR and HDX-MS Technological Platform, CNRS UMR3528, Paris, France
| | - Catriona Walls
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Janet A. Willment
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom,Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, United Kingdom
| | - Neil A. R. Gow
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom,Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, United Kingdom
| | - Carol A. Munro
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Gordon D. Brown
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom,Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, United Kingdom
| | - Leila M. Lopes-Bezerra
- Cell Biology Department, Rio de Janeiro State University, Rio de Janeiro, Brazil,Biomedical Institute and Technology and Innovation Center (CIETEC), São Paulo University, São Paulo, Brazil,*Correspondence: Leila M. Lopes-Bezerra,
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7
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Hasegawa Y, Nagano K. Porphyromonas gingivalis FimA and Mfa1 fimbriae: Current insights on localization, function, biogenesis, and genotype. JAPANESE DENTAL SCIENCE REVIEW 2021; 57:190-200. [PMID: 34691295 PMCID: PMC8512630 DOI: 10.1016/j.jdsr.2021.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/16/2021] [Accepted: 09/21/2021] [Indexed: 11/16/2022] Open
Abstract
In general, the periodontal pathogen Porphyromonas gingivalis expresses distinct FimA and Mfa1 fimbriae. Each of these consists of five FimA–E and five Mfa1–5 proteins encoded by the fim and mfa gene clusters, respectively. The main shaft portion comprises FimA and Mfa1, whereas FimB and Mfa2 are localized on the basal portion and function as anchors and elongation terminators. FimC–E and Mfa3–5 participate in the assembly of an accessory protein complex on the tips of each fimbria. Hence, they serve as ligands for the receptors on host cells and other oral bacterial species. The crystal structures of FimA and Mfa1 fimbrial proteins were recently elucidated and new insights into the localization, function, and biogenesis of these proteins have been reported. Several studies indicated a correlation between P. gingivalis pathogenicity and the fimA genotype but not the mfa1 genotype. We recently revealed polymorphisms of all genes in the fim and mfa gene clusters. Intriguingly, mfa5 occurred in numerous different forms and underwent duplication. Detailed structural and functional knowledge of the fimbrial proteins in the context of the entire filament could facilitate the development of innovative therapeutic strategies for structure-based drug design.
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Affiliation(s)
- Yoshiaki Hasegawa
- Department of Microbiology, School of Dentistry, Aichi Gakuin University, Nagoya, Japan
| | - Keiji Nagano
- Division of Microbiology, Department of Oral Biology, School of Dentistry, Health Sciences University of Hokkaido, Hokkaido, Japan
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8
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Porphyromonas gingivalis Mfa1 Induces Chemokine and Cell Adhesion Molecules in Mouse Gingival Fibroblasts via Toll-Like Receptors. J Clin Med 2020; 9:jcm9124004. [PMID: 33322059 PMCID: PMC7764148 DOI: 10.3390/jcm9124004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 11/16/2022] Open
Abstract
Porphyromonas gingivalis Mfa1 fimbriae are thought to act as adhesion factors and to direct periodontal tissue destruction but their immunomodulatory actions are poorly understood. Here, we investigated the effect of Mfa1 stimulation on the immune and metabolic mechanisms of gingival fibroblasts from periodontal connective tissue. We also determined the role of Toll-like receptor (TLR) 2 and TLR4 in Mfa1 recognition. Mfa1 increased the expression of genes encoding chemokine (C-X-C motif) ligand (CXCL) 1, CXCL3, intercellular adhesion molecule (ICAM) 1 and Selectin endothelium (E) in gingival fibroblasts, but did not have a significant effect on genes that regulate metabolism. Mfa1-stimulated up-regulation of genes was significantly suppressed in Tlr4 siRNA-transfected cells compared with that in control siRNA-transfected cells, which indicates that recognition by TLR4 is essential for immunomodulation by Mfa1. Additionally, suppression of Tlr2 expression partially attenuated the stimulatory effect of Mfa1. Overall, these results help explain the involvement of P. gingivalis Mfa1 fimbriae in the progression of periodontal disease.
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9
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Autotransporter-Mediated Display of Complement Receptor Ligands by Gram-Negative Bacteria Increases Antibody Responses and Limits Disease Severity. Pathogens 2020; 9:pathogens9050375. [PMID: 32422907 PMCID: PMC7281241 DOI: 10.3390/pathogens9050375] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/06/2020] [Accepted: 05/11/2020] [Indexed: 12/13/2022] Open
Abstract
The targeting of immunogens/vaccines to specific immune cells is a promising approach for amplifying immune responses in the absence of exogenous adjuvants. However, the targeting approaches reported thus far require novel, labor-intensive reagents for each vaccine and have primarily been shown as proof-of-concept with isolated proteins and/or inactivated bacteria. We have engineered a plasmid-based, complement receptor-targeting platform that is readily applicable to live forms of multiple gram-negative bacteria, including, but not limited to, Escherichia coli, Klebsiella pneumoniae, and Francisella tularensis. Using F. tularensis as a model, we find that targeted bacteria show increased binding and uptake by macrophages, which coincides with increased p38 and p65 phosphorylation. Mice vaccinated with targeted bacteria produce higher titers of specific antibody that recognizes a greater diversity of bacterial antigens. Following challenge with homologous or heterologous isolates, these mice exhibited less weight loss and/or accelerated weight recovery as compared to counterparts vaccinated with non-targeted immunogens. Collectively, these findings provide proof-of-concept for plasmid-based, complement receptor-targeting of live gram-negative bacteria.
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10
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Hajishengallis G, Diaz PI. Porphyromonas gingivalis: Immune subversion activities and role in periodontal dysbiosis. ACTA ACUST UNITED AC 2020; 7:12-21. [PMID: 33344104 DOI: 10.1007/s40496-020-00249-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Purpose of review This review summarizes mechanisms by which Porphyromonas gingivalis interacts with community members and the host so that it can persist in the periodontium under inflammatory conditions that drive periodontal disease. Recent findings Recent advances indicate that, in great part, the pathogenicity of P. gingivalis is dependent upon its ability to establish residence in the subgingival environment and to subvert innate immunity in a manner that uncouples the nutritionally favorable (for the bacteria) inflammatory response from antimicrobial pathways. While the initial establishment of P. gingivalis is dependent upon interactions with early colonizing bacteria, the immune subversion strategies of P. gingivalis in turn benefit co-habiting species. Summary Specific interspecies interactions and subversion of the host response contribute to the emergence and persistence of dysbiotic communities and are thus targets of therapeutic approaches for the treatment of periodontitis.
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Affiliation(s)
- George Hajishengallis
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, 240 S. 40 Street, Philadelphia, PA 19104, USA
| | - Patricia I Diaz
- Division of Periodontology, Department of Oral Health and Diagnostic Sciences, UConn Health, 263 Farmington Avenue, Farmington, CT 06030, USA
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11
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Padhi A, Pattnaik K, Biswas M, Jagadeb M, Behera A, Sonawane A. Mycobacterium tuberculosisLprE Suppresses TLR2-Dependent Cathelicidin and Autophagy Expression to Enhance Bacterial Survival in Macrophages. THE JOURNAL OF IMMUNOLOGY 2019; 203:2665-2678. [DOI: 10.4049/jimmunol.1801301] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 09/15/2019] [Indexed: 12/20/2022]
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12
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Kumar V. The complement system, toll-like receptors and inflammasomes in host defense: three musketeers’ one target. Int Rev Immunol 2019; 38:131-156. [DOI: 10.1080/08830185.2019.1609962] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Vijay Kumar
- Children’s Health Queensland Clinical Unit, School of Clinical Medicine, Faculty of Medicine, Mater Research, University of Queensland, St Lucia, Brisbane, QLD, Australia
- School of Biomedical Sciences, Faculty of Medicine, University of Queensland, ST Lucia, Brisbane, QLD, Australia
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13
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Tamai R, Kiyoura Y. Heat-killed Candida albicans augments synthetic bacterial component-induced proinflammatory cytokine production. Folia Microbiol (Praha) 2019; 64:555-566. [PMID: 30656591 DOI: 10.1007/s12223-019-00679-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 01/07/2019] [Indexed: 12/23/2022]
Abstract
Candida albicans can enhance the invasion of oral epithelial cells by Porphyromonas gingivalis, although the fungus is not a periodontal pathogen. In this study, we investigated whether C. albicans augments proinflammatory cytokine production by mouse macrophage-like J774.1 cells incubated with synthetic bacterial components. Mouse macrophage-like J774.1 cells, mouse primary splenocytes, human THP-1 cells, and A549 cells were pretreated with or without heat-killed C. albicans (HKCA) or substitutes for C. albicans cell wall components in 96-well flat-bottomed plates. Cells were then washed and incubated with Pam3CSK4, a Toll-like receptor (TLR) 2 ligand, or lipid A, a TLR4 ligand. Culture supernatants were analyzed by ELISA for secreted IL-6, MCP-1, TNF-α, and IL-8. HKCA augmented TLR ligand-induced proinflammatory cytokine production by J774.1 cells, mouse splenocytes, and THP-1 cells, but not A549 cells. However, IL-6, MCP-1, and TNF-α production induced by Pam3CSK4 or lipid A was not augmented when cells were pretreated with curdlan, a dectin-1 ligand, or mannan, a dectin-2 ligand. In contrast, pretreatment of cells with TLR ligands upregulated the production of IL-6 and TNF-α, but not MCP-1, induced by Pam3CSK4 or lipid A. The results suggest that C. albicans augments synthetic bacterial component-induced cytokine production by J774.1 cells via the TLR pathway, but not the dectin-1 or dectin-2 pathway.
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Affiliation(s)
- Riyoko Tamai
- Department of Oral Medical Science, Ohu University School of Dentistry, 31-1 Misumido, Tomitamachi, Koriyama, Fukushima, 963-8611, Japan.
| | - Yusuke Kiyoura
- Department of Oral Medical Science, Ohu University School of Dentistry, 31-1 Misumido, Tomitamachi, Koriyama, Fukushima, 963-8611, Japan
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14
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Tseng HY, Samarelli AV, Kammerer P, Scholze S, Ziegler T, Immler R, Zent R, Sperandio M, Sanders CR, Fässler R, Böttcher RT. LCP1 preferentially binds clasped αMβ2 integrin and attenuates leukocyte adhesion under flow. J Cell Sci 2018; 131:jcs.218214. [PMID: 30333137 DOI: 10.1242/jcs.218214] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 09/07/2018] [Indexed: 12/13/2022] Open
Abstract
Integrins are α/β heterodimers that interconvert between inactive and active states. In the active state the α/β cytoplasmic domains recruit integrin-activating proteins and separate the transmembrane and cytoplasmic (TMcyto) domains (unclasped TMcyto). Conversely, in the inactive state the α/β TMcyto domains bind integrin-inactivating proteins, resulting in the association of the TMcyto domains (clasped TMcyto). Here, we report the isolation of integrin cytoplasmic tail interactors using either lipid bicelle-incorporated integrin TMcyto domains (α5, αM, αIIb, β1, β2 and β3 integrin TMcyto) or a clasped, lipid bicelle-incorporated αMβ2 TMcyto. Among the proteins found to preferentially bind clasped rather than the isolated αM and β2 subunits was L-plastin (LCP1, also known as plastin-2), which binds to and maintains the inactive state of αMβ2 integrin in vivo and thereby regulates leukocyte adhesion to integrin ligands under flow. Our findings offer a global view on cytoplasmic proteins interacting with different integrins and provide evidence for the existence of conformation-specific integrin interactors.
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Affiliation(s)
- Hui-Yuan Tseng
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Anna V Samarelli
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Patricia Kammerer
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Sarah Scholze
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Tilman Ziegler
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany
| | - Roland Immler
- Walter Brendel Center for Experimental Medicine, Ludwig-Maximilians-University, 81377 Munich, Germany
| | - Roy Zent
- Division of Nephrology, Department of Medicine, Vanderbilt University, Nashville, 37232 Tennessee, USA.,Department of Medicine, Veterans Affairs Medical Center, Nashville, 37232 Tennessee, USA
| | - Markus Sperandio
- Walter Brendel Center for Experimental Medicine, Ludwig-Maximilians-University, 81377 Munich, Germany
| | - Charles R Sanders
- Department of Biochemistry, Center for Structural Biology, and Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, 37232 Tennessee, USA
| | - Reinhard Fässler
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, 80802 Munich, Germany
| | - Ralph T Böttcher
- Department of Molecular Medicine, Max Planck Institute for Biochemistry, 82152 Martinsried, Germany .,DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, 80802 Munich, Germany
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15
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Wallet SM, Puri V, Gibson FC. Linkage of Infection to Adverse Systemic Complications: Periodontal Disease, Toll-Like Receptors, and Other Pattern Recognition Systems. Vaccines (Basel) 2018; 6:E21. [PMID: 29621153 PMCID: PMC6027258 DOI: 10.3390/vaccines6020021] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/25/2018] [Accepted: 03/30/2018] [Indexed: 12/13/2022] Open
Abstract
Toll-like receptors (TLRs) are a group of pattern recognition receptors (PRRs) that provide innate immune sensing of conserved pathogen-associated molecular patterns (PAMPs) to engage early immune recognition of bacteria, viruses, and protozoa. Furthermore, TLRs provide a conduit for initiation of non-infectious inflammation following the sensing of danger-associated molecular patterns (DAMPs) generated as a consequence of cellular injury. Due to their essential role as DAMP and PAMP sensors, TLR signaling also contributes importantly to several systemic diseases including cardiovascular disease, diabetes, and others. The overlapping participation of TLRs in the control of infection, and pathogenesis of systemic diseases, has served as a starting point for research delving into the poorly defined area of infection leading to increased risk of various systemic diseases. Although conflicting studies exist, cardiovascular disease, diabetes, cancer, rheumatoid arthritis, and obesity/metabolic dysfunction have been associated with differing degrees of strength to infectious diseases. Here we will discuss elements of these connections focusing on the contributions of TLR signaling as a consequence of bacterial exposure in the context of the oral infections leading to periodontal disease, and associations with metabolic diseases including atherosclerosis and type 2 diabetes.
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Affiliation(s)
- Shannon M Wallet
- Department of Oral Biology, College of Dental Medicine, University of Florida, Gainesville, FL 32610, USA.
| | - Vishwajeet Puri
- Department of Biomedical Sciences and Diabetes Institute, Ohio University, Athens, OH 45701, USA.
| | - Frank C Gibson
- Department of Oral Biology, College of Dental Medicine, University of Florida, Gainesville, FL 32610, USA.
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16
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Porphyromonas gulae Activates Unprimed and Gamma Interferon-Primed Macrophages via the Pattern Recognition Receptors Toll-Like Receptor 2 (TLR2), TLR4, and NOD2. Infect Immun 2017. [PMID: 28630066 DOI: 10.1128/iai.00282-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Porphyromonas gulae is an anaerobic, Gram-negative coccobacillus that has been associated with periodontal disease in companion animals. The aims of this study were to analyze the ligation of pattern recognition receptors by P. gulae and the subsequent activation of macrophages. Exposure of HEK cells transfected with Toll-like receptors (TLRs) or NOD-like receptors to P. gulae resulted in the ligation of TLR2, TLR4, and NOD2. The effects of this engagement of receptors were investigated by measuring the synthesis of nitric oxide (NO), CD86 expression, and inflammatory cytokine production by wild-type, TLR2-/-, and TLR4-/- macrophages. The addition of P. gulae to unprimed and gamma interferon (IFN-γ)-primed (M1 phenotype) macrophages significantly increased the surface expression of CD86, but only M1 macrophages produced nitric oxide. P. gulae-induced expression of CD86 on unprimed macrophages was dependent on both TLR2 and TLR4, but CD86 expression and NO production in M1 macrophages were only TLR2 dependent. P. gulae induced an increase in secretion of interleukin-1α (IL-1α), IL-1β, IL-6, IL-12p70, IL-13, tumor necrosis factor alpha (TNF-α), granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein 1 (MCP-1), and macrophage inflammatory protein 1α (MIP-1α) by M1 macrophages compared to that by unprimed controls. Among these cytokines, secretion of IL-6 and TNF-α by M1 macrophages was dependent on either TLR2 or TLR4. Our data indicate that TLR2 and TLR4 are important for P. gulae activation of unprimed macrophages and that activation and effector functions induced in M1 macrophages by P. gulae are mainly dependent on TLR2. In conclusion, P. gulae induces a strong TLR2-dependent inflammatory M1 macrophage response which may be important in establishing the chronic inflammation associated with periodontal disease in companion animals.
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17
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Hajishengallis G, Lambris JD. More than complementing Tolls: complement-Toll-like receptor synergy and crosstalk in innate immunity and inflammation. Immunol Rev 2017; 274:233-244. [PMID: 27782328 DOI: 10.1111/imr.12467] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Complement and Toll-like receptors (TLRs) play key roles in the host immune response and are swiftly activated by infection or other types of immunological stress. This review focuses on the capacity of complement and TLRs to engage in signaling crosstalk, ostensibly to coordinate immune and inflammatory responses through synergistic or antagonistic (regulatory) interactions. However, overactivation or dysregulation of either system may lead-often synergistically-to exaggerated inflammation and host tissue injury. Intriguingly, moreover, certain pathogens can manipulate complement-TLR crosstalk pathways in ways that undermine host immunity and favor their persistence. In the setting of polymicrobial inflammatory disease, subversion of complement-TLR crosstalk by keystone pathogens can promote dysbiosis. Knowledge of the molecular mechanisms underlying complement-TLR crosstalk pathways can, therefore, be used productively for tailored therapeutic approaches, such as, to enhance host immunity, mitigate destructive inflammation, or counteract microbial subversion of the host response.
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Affiliation(s)
- George Hajishengallis
- Department of Microbiology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA, USA.
| | - John D Lambris
- Perelman School of Medicine, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
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18
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Olsen I, Lambris JD, Hajishengallis G. Porphyromonas gingivalis disturbs host-commensal homeostasis by changing complement function. J Oral Microbiol 2017; 9:1340085. [PMID: 28748042 PMCID: PMC5508361 DOI: 10.1080/20002297.2017.1340085] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 06/06/2017] [Indexed: 02/07/2023] Open
Abstract
Porphyromonas gingivalis is a Gram-negative anaerobic rod that has been proposed as an orchestrator of complement-dependent dysbiotic inflammation. This notion was suggested from its capacities to manipulate the complement–Toll-like receptor crosstalk in ways that promote dysbiosis and periodontal disease in animal models. Specifically, while at low colonization levels, P. gingivalis interferes with innate immunity and leads to changes in the counts and composition of the oral commensal microbiota. The resulting dysbiotic microbial community causes disruption of host–microbial homeostasis, leading to inflammatory bone loss. These findings suggested that P. gingivalis can be considered as a keystone pathogen. The concept of keystone pathogens is one where their effects have community-wide significance and are disproportionate of their abundance. The present review summarizes the relevant literature and discusses whether the results from the animal models can be extrapolated to man.
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Affiliation(s)
- Ingar Olsen
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - John D Lambris
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, PA, USA
| | - George Hajishengallis
- Department of Microbiology, School of Dental Medicine; University of Pennsylvania, PA, USA
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19
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Sochalska M, Potempa J. Manipulation of Neutrophils by Porphyromonas gingivalis in the Development of Periodontitis. Front Cell Infect Microbiol 2017; 7:197. [PMID: 28589098 PMCID: PMC5440471 DOI: 10.3389/fcimb.2017.00197] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 05/04/2017] [Indexed: 12/31/2022] Open
Abstract
The pathogenesis of the chronic periodontal disease is associated with a skewed host inflammatory response to periodontal pathogens, such as Porphyromonas gingivalis, that accounts for the majority of periodontal tissue damage. Neutrophils are the most abundant leukocytes in periodontal pockets and depending on the stage of the disease, also plentiful PMNs are present in the inflamed gingival tissue and the gingival crevice. They are the most efficient phagocytes and eliminate pathogens by a variety of means, which are either oxygen-dependent or -independent. However, these secretory lethal weapons do not strictly discriminate between pathogens and host tissue. Current studies describe conflicting findings about neutrophil involvement in periodontal disease. On one hand literature indicate that hyper-reactive neutrophils are the main immune cell type responsible for this observed tissue damage and disease progression. Deregulation of neutrophil survival and functions, such as chemotaxis, migration, secretion of antimicrobial peptides or enzymes, and production of reactive oxygen species, contribute to observed tissue injury and the clinical signs of periodontal disease. On the other hand neutrophils deficiencies in patients and mice also result in periodontal phenotype. Therefore, P. gingivalis represents a periodontal pathogen that manipulates the immune responses of PMNs, employing several virulence factors, such as gingipains, serine proteases, lipid phosphatases, or fimbriae. This review will sum up studies devoted to understanding different strategies utilized by P. gingivalis to manipulate PMNs survival and functions in order to inhibit killing by a granular content, prolong inflammation, and gain access to nutrient resources.
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Affiliation(s)
- Maja Sochalska
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian UniversityKrakow, Poland
| | - Jan Potempa
- Department of Microbiology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian UniversityKrakow, Poland.,Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of LouisvilleLouisville, KY, United States
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20
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Chen HY, Lin MH, Chen CC, Shu JC. The expression of fibronectin is significantly suppressed in macrophages to exert a protective effect against Staphylococcus aureus infection. BMC Microbiol 2017; 17:92. [PMID: 28407745 PMCID: PMC5390343 DOI: 10.1186/s12866-017-1003-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 04/07/2017] [Indexed: 11/20/2022] Open
Abstract
Background Fibronectin (Fn) plays a major role in the attachment of Staphylococcus aureus to host cells by bridging staphylococcal fibronectin-binding proteins (FnBPs) and cell-surface integrins. A previous study demonstrated that the phagocytosis of S. aureus by macrophages is enhanced in the presence of exogenous Fn. We recently found that FnBPs overexpression also enhances phagocytic activity. The effect of S. aureus infection on the expression of macrophage Fn was investigated. Result The level of Fn secreted by monocytes (THP-1), macrophages, human lung adenocarcinoma (A549) cells, and hepatocellular carcinoma (HepG2) cells in response to S. aureus infection was determined by Western blotting and it was significantly suppressed only in macrophages. The activation of signaling pathways associated with Fn regulation in macrophages and HepG2 cells was also investigated by Western blotting. Erk was activated in both macrophages and HepG2 cells, whereas Src-JNK-c-Jun signaling was only activated in macrophages. A significant decrease in macrophage viability was observed in response to S. aureus infection in the presence of exogenous Fn. Conclusion The Src-JNK-c-Jun signaling pathway was activated in macrophages in response to S. aureus infection and resulted in the suppression of Fn expression. This suppression may play a protective role in macrophages against S. aureus infection. This study provides the first demonstration that Fn is suppressed in macrophages by S. aureus infection. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-1003-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hong-Yi Chen
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, No. 259, Wenhua 1st Road, Guishan, Taoyuan, 333, Taiwan
| | - Mei-Hui Lin
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, No. 259, Wenhua 1st Road, Guishan, Taoyuan, 333, Taiwan.,Research Center for Pathogenic Bacteria, Chang Gung University, Taoyuan, Taiwan.,Department of Laboratory Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Chien-Cheng Chen
- Department of Biotechnology, National Kaohsiung Normal University, Kaohsiung, Taiwan
| | - Jwu-Ching Shu
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, No. 259, Wenhua 1st Road, Guishan, Taoyuan, 333, Taiwan. .,Research Center for Pathogenic Bacteria, Chang Gung University, Taoyuan, Taiwan. .,Department of Laboratory Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
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21
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Nozoe K, Sanui T, Takeshita M, Fukuda T, Haraguchi A, Aida Y, Nishimura F. Innate immune-stimulatory activity of Porphyromonas gingivalis fimbriae is eliminated by phase separation using Triton X-114. J Immunol Methods 2016; 441:31-38. [PMID: 27913143 DOI: 10.1016/j.jim.2016.11.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/19/2016] [Accepted: 11/21/2016] [Indexed: 01/01/2023]
Abstract
Fimbriae are virulence factors of Porphyromonas gingivalis (P. gingivalis). In this study, the action of fimbriae on neutrophil respiratory burst and cytokine production by mononuclear cells (MNC) were investigated. Native or denatured form of purified P. gingivalis fimbriae contained endotoxin at an equivalence of 1-3μglipopolysaccharides(LPS)/mg protein. The endotoxin could be reduced to the equivalent of 1ng-LPS/mg protein by phase separation using Triton X-114. Unfractionated fimbriae caused serum-dependent priming of neutrophils for enhanced respiratory burst, but both native and denatured forms of Triton X-114-fractionated fimbriae were not active at 100μg/mL. Unfractionated fimbriae induced serum-dependent production of IL-1β by MNC. Triton X-114-fractionated fimbriae (10μg/mL)-induced production of IL-1β, IL-8 or TNF-α was much lower than that induced by unfractionated fimbriae or 10ng/mL P. gingivalis-LPS preparation. Triton X-114-fractionated fimbriae immobilized on polystyrene tubes induced adhesion-stimulated superoxide release by LPS-primed neutrophils in a β2 integrin-dependent manner. P. gingivalis cells caused priming of neutrophils; however, Toll-like receptor (TLR) 4 antagonists did not affect this response. Thus, P. gingivalis fimbriae were ineffective in inducing innate immune response in leukocytes; however, they induced β2 integrin-mediated response by neutrophils. Immune-stimulatory components of P. gingivalis might be recognized by receptors other than TLR4.
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Affiliation(s)
- Kohji Nozoe
- Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Terukazu Sanui
- Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Masaaki Takeshita
- Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Takao Fukuda
- Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Akira Haraguchi
- Division of General Dentistry, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
| | - Yoshitomi Aida
- Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
| | - Fusanori Nishimura
- Section of Periodontology, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan
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22
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Hajishengallis G, Krauss JL, Jotwani R, Lambris JD. Differential capacity for complement receptor-mediated immune evasion by Porphyromonas gingivalis depending on the type of innate leukocyte. Mol Oral Microbiol 2016; 32:154-165. [PMID: 27081768 DOI: 10.1111/omi.12161] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2016] [Indexed: 01/02/2023]
Abstract
The complement system plays a central role in immunity and inflammation, although certain pathogens can exploit complement to undermine protective immunity. In this context, the periodontal keystone pathogen Porphyromonas gingivalis was previously shown by our group to evade killing by neutrophils or macrophages through exploitation of complement C5a receptor 1 (C5aR1) and complement receptor 3 (CR3). Here, we examined whether P. gingivalis uses complement receptors to also subvert killing by dendritic cells. In line with earlier independent studies, intracellular viable P. gingivalis bacteria could be recovered from mouse bone-marrow-derived dendritic cells (BMDC) or human monocyte-derived dendritic cells (MDDC) exposed to the pathogen. However, in the presence of C5a, the intracellular survival of P. gingivalis was significantly decreased in a C5aR1-dependent way. Further work using wild-type and receptor-knockout BMDC showed that, in the presence of C3a, the C3a receptor (C3aR) similarly enhanced the intracellular killing of P. gingivalis. In contrast, C5aR2, an alternative receptor for C5a (G protein-coupled receptor 77), was associated with increased intracellular P. gingivalis viable counts, consistent with the notion that C5aR2 functions as a negative regulator of C5aR1 activity. Moreover, P. gingivalis failed to use CR3 as a phagocytic receptor in BMDC, in contrast to our earlier findings in macrophages where CR3-mediated uptake promotes P. gingivalis survival. Collectively, these data show that complement receptors mediate cell-type-specific effects on how innate leukocytes handle P. gingivalis, which appears to exploit complement to preferentially evade those cells (neutrophils and macrophages) that are most often encountered in its predominant niche, the periodontal pocket.
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Affiliation(s)
- G Hajishengallis
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - J L Krauss
- Department of Oral Immunology and Infectious Diseases, University of Louisville, Louisville, KY, USA
| | - R Jotwani
- Department of Oral Immunology and Infectious Diseases, University of Louisville, Louisville, KY, USA
| | - J D Lambris
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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23
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PE_PGRS33 Contributes to Mycobacterium tuberculosis Entry in Macrophages through Interaction with TLR2. PLoS One 2016; 11:e0150800. [PMID: 26978522 PMCID: PMC4792380 DOI: 10.1371/journal.pone.0150800] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 02/20/2016] [Indexed: 01/01/2023] Open
Abstract
PE_PGRS represent a large family of proteins typical of pathogenic mycobacteria whose members are characterized by an N-terminal PE domain followed by a large Gly-Ala repeat-rich C-terminal domain. Despite the abundance of PE_PGRS-coding genes in the Mycobacterium tuberculosis (Mtb) genome their role and function in the biology and pathogenesis still remains elusive. In this study, we generated and characterized an Mtb H37Rv mutant (MtbΔ33) in which the structural gene of PE_PGRS33, a prototypical member of the protein family, was inactivated. We showed that this mutant entered macrophages with an efficiency up to ten times lower than parental or complemented strains, while its efficiency in infecting pneumocytes remained unaffected. Interestingly, the lack of PE_PGRS33 did not affect the intracellular growth of this mutant in macrophages. Using a series of functional deletion mutants of the PE_PGRS33 gene to complement the MtbΔ33 strain, we demonstrated that the PGRS domain is required to mediate cell entry into macrophages, with the key domain encompassing position 140–260 amino acids of PE_PGRS33. PE_PGRS33-mediated entry into macrophages was abolished in TLR2-deficient mice, as well as following treatment with wortmannin or an antibody against the complement receptor 3 (CR3), indicating that PE_PGRS33-mediated entry of Mtb in macrophages occurs through interaction with TLR2.
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24
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Hussein HAM, Walker LR, Abdel-Raouf UM, Desouky SA, Montasser AKM, Akula SM. Beyond RGD: virus interactions with integrins. Arch Virol 2015; 160:2669-81. [PMID: 26321473 PMCID: PMC7086847 DOI: 10.1007/s00705-015-2579-8] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 08/21/2015] [Indexed: 12/30/2022]
Abstract
Viruses successfully infect host cells by initially binding to the surfaces of the cells, followed by an intricate entry process. As multifunctional heterodimeric cell-surface receptor molecules, integrins have been shown to usefully serve as entry receptors for a plethora of viruses. However, the exact role(s) of integrins in viral pathogen internalization has yet to be elaborately described. Notably, several viruses harbor integrin-recognition motifs displayed on viral envelope/capsid-associated proteins. The most common of these motifs is the minimal peptide sequence for binding integrins, RGD (Arg-Gly-Asp), which is known for its role in virus infection via its ability to interact with over half of the more than 20 known integrins. Not all virus-integrin interactions are RGD-dependent, however. Non-RGD-binding integrins have also been shown to effectively promote virus entry and infection as well. Such virus-integrin binding is shown to facilitate adhesion, cytoskeleton rearrangement, integrin activation, and increased intracellular signaling. Also, we have attempted to discuss the role of carbohydrate moieties in virus interactions with receptor-like host cell surface integrins that drive the process of internalization. As much as possible, this article examines the published literature regarding the role of integrins in terms of virus infection and virus-encoded glycosylated proteins that mediate interactions with integrins, and it explores the idea of targeting these receptors as a therapeutic treatment option.
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Affiliation(s)
- Hosni A M Hussein
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, 27834, USA
| | - Lia R Walker
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, 27834, USA
| | - Usama M Abdel-Raouf
- Faculty of Science, Al Azhar University, Assiut Branch, Assiut, 71524, Egypt
| | - Sayed A Desouky
- Faculty of Science, Al Azhar University, Assiut Branch, Assiut, 71524, Egypt
| | | | - Shaw M Akula
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, 27834, USA.
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25
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CR3 and Dectin-1 Collaborate in Macrophage Cytokine Response through Association on Lipid Rafts and Activation of Syk-JNK-AP-1 Pathway. PLoS Pathog 2015; 11:e1004985. [PMID: 26132276 PMCID: PMC4488469 DOI: 10.1371/journal.ppat.1004985] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Accepted: 05/27/2015] [Indexed: 01/08/2023] Open
Abstract
Collaboration between heterogeneous pattern recognition receptors (PRRs) leading to synergistic coordination of immune response is important for the host to fight against invading pathogens. Although complement receptor 3 (CR3) and Dectin-1 are major PRRs to detect fungi, crosstalk between these two receptors in antifungal immunity is largely undefined. Here we took advantage of Histoplasma capsulatum which is known to interact with both CR3 and Dectin-1 and specific particulate ligands to study the collaboration of CR3 and Dectin-1 in macrophage cytokine response. By employing Micro-Western Array (MWA), genetic approach, and pharmacological inhibitors, we demonstrated that CR3 and Dectin-1 act collaboratively to trigger macrophage TNF and IL-6 response through signaling integration at Syk kinase, allowing subsequent enhanced activation of Syk-JNK-AP-1 pathway. Upon engagement, CR3 and Dectin-1 colocalize and form clusters on lipid raft microdomains which serve as a platform facilitating their cooperation in signaling activation and cytokine production. Furthermore, in vivo studies showed that CR3 and Dectin-1 cooperatively participate in host defense against disseminated histoplasmosis and instruct adaptive immune response. Taken together, our findings define the mechanism of receptor crosstalk between CR3 and Dectin-1 and demonstrate the importance of their collaboration in host defense against fungal infection. The incidence of life-threatening fungal infections is increasing during the last decades. A better understanding of the interactions between fungal pathogen and its host cell is important to the development of new therapeutic strategies against fungal infections. Dimorphic fungus Histoplasma capsulatum becomes disseminated and threatens life in immunocompromised individuals. This fungal pathogen utilizes complement receptor 3 (CR3) and Dectin-1, two pattern recognition receptors on the surface of innate immune cells, to induce macrophage cytokine response. In this study, we demonstrated that CR3 and Dectin-1 act collaboratively to induce macrophage TNF and IL-6 response through a mechanism dependent on activation of the Syk-JNK-AP-1 signaling axis. CR3 and Dectin-1 are recruited and form clusters on lipid raft microdomains upon stimulation by H. capsulatum, leading to activation of their signaling convergence at Syk kinase and induction of subsequent cytokine response. In addition, we showed that CR3 and Dectin-1 cooperatively instruct the adaptive antifungal immunity to defense against H. capsulatum infection. Our findings define the molecular mechanisms underlying receptor crosstalk between CR3 and Dectin-1 and provide a valuable model for receptor collaboration in the context of host-fungus interactions.
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26
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The negative feedback regulation of microRNA-146a in human periodontal ligament cells after Porphyromonas gingivalis lipopolysaccharide stimulation. Inflamm Res 2015; 64:441-51. [DOI: 10.1007/s00011-015-0824-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 04/20/2015] [Accepted: 04/20/2015] [Indexed: 12/18/2022] Open
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27
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Adhesion of monocytes to periodontal fibroblasts requires activation of NOD1/2- and TLR4-mediated LFA-1 and VLA-4. Arch Oral Biol 2014; 60:834-44. [PMID: 25791323 DOI: 10.1016/j.archoralbio.2014.12.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 12/12/2014] [Accepted: 12/14/2014] [Indexed: 12/17/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the roles of nucleotide-binding oligomerization domain-containing protein 1/2 (NOD1/2) and Toll-like receptor 4 (TLR4) in mediating the adhesion of monocytes to periodontal fibroblasts through leucocyte function-associated antigen-1 (LFA-1) and very late antigen-4 (VLA-4). DESIGN The expression of NOD1, NOD2, and TLR4 was detected in the gingival tissue of patients with chronic periodontitis by immunohistochemistry. Then the adhesion of cells of human monocytic cell line U937 to human gingival fibroblasts (hGFs) and human periodontal ligament cells (hPDLCs) was investigated after U937 cells were treated with the agonists of NOD1, NOD2, and TLR4 for 24 h, or transfected with small interfering RNAs (siRNAs) targeting NOD1, NOD2, and TLR4 for 48 h. Meanwhile, the expression of LFA-1 and VLA-4 was examined in U937 cells through real-time polymerase chain reaction (PCR), Western blot, and flow cytometry. To confirm the roles of LFA-1 and VLA-4 involved in the process of adhesion, the adhesion blockade assay was performed using the corresponding blocking antibodies against these adhesion molecules. RESULTS The immunostaining results showed that NOD1, NOD2, and TLR4 were highly expressed in the gingival tissue of patients with periodontitis, especially in the monocyte-infiltrated area. The activation of these receptors by agonists upregulated the expression of LFA-1 and VLA-4 in U937 cells, and it increased the affinity of U937 cells to hGFs or hPDLCs. On the other hand, knockdown of these receptors by specific siRNAs resulted in the opposite results. In addition, blocking either LFA-1 or VLA-4 in U937 cells significantly attenuated the agonist-triggered adhesion of U937 to periodontal fibroblasts (P<0.001). CONCLUSIONS These results suggested that NOD1/2 and TLR4 mediated monocyte-periodontal fibroblast adhesion via the modulation of LFA-1 and VLA-4.
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28
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Ji S, Choi YS, Choi Y. Bacterial invasion and persistence: critical events in the pathogenesis of periodontitis? J Periodontal Res 2014; 50:570-85. [DOI: 10.1111/jre.12248] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2014] [Indexed: 12/22/2022]
Affiliation(s)
- S. Ji
- Department of Periodontology Anam Hospital Korea University Seoul Korea
| | - Y. S. Choi
- Department of Immunology and Molecular Microbiology and Dental Research Institute School of Dentistry Seoul National University Seoul Korea
| | - Y. Choi
- Department of Immunology and Molecular Microbiology and Dental Research Institute School of Dentistry Seoul National University Seoul Korea
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Mitroulis I, Alexaki VI, Kourtzelis I, Ziogas A, Hajishengallis G, Chavakis T. Leukocyte integrins: role in leukocyte recruitment and as therapeutic targets in inflammatory disease. Pharmacol Ther 2014; 147:123-135. [PMID: 25448040 DOI: 10.1016/j.pharmthera.2014.11.008] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 11/06/2014] [Indexed: 02/06/2023]
Abstract
Infection or sterile inflammation triggers site-specific attraction of leukocytes. Leukocyte recruitment is a process comprising several steps orchestrated by adhesion molecules, chemokines, cytokines and endogenous regulatory molecules. Distinct adhesive interactions between endothelial cells and leukocytes and signaling mechanisms contribute to the temporal and spatial fine-tuning of the leukocyte adhesion cascade. Central players in the leukocyte adhesion cascade include the leukocyte adhesion receptors of the β2-integrin family, such as the αLβ2 and αMβ2 integrins, or of the β1-integrin family, such as the α4β1-integrin. Given the central involvement of leukocyte recruitment in different inflammatory and autoimmune diseases, the leukocyte adhesion cascade in general, and leukocyte integrins in particular, represent key therapeutic targets. In this context, the present review focuses on the role of leukocyte integrins in the leukocyte adhesion cascade. Experimental evidence that has implicated leukocyte integrins as targets in animal models of inflammatory disorders, such as experimental autoimmune encephalomyelitis, psoriasis, inflammatory bone loss and inflammatory bowel disease as well as preclinical and clinical therapeutic applications of antibodies that target leukocyte integrins in various inflammatory disorders are presented. Finally, we review recent findings on endogenous inhibitors that modify leukocyte integrin function, which could emerge as promising therapeutic targets.
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Affiliation(s)
- Ioannis Mitroulis
- Department of Clinical Pathobiochemistry and Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
| | - Vasileia I Alexaki
- Department of Clinical Pathobiochemistry and Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
| | - Ioannis Kourtzelis
- Department of Clinical Pathobiochemistry and Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
| | - Athanassios Ziogas
- Department of Clinical Pathobiochemistry and Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
| | - George Hajishengallis
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Triantafyllos Chavakis
- Department of Clinical Pathobiochemistry and Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
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Costalonga M, Herzberg MC. The oral microbiome and the immunobiology of periodontal disease and caries. Immunol Lett 2014; 162:22-38. [PMID: 25447398 DOI: 10.1016/j.imlet.2014.08.017] [Citation(s) in RCA: 381] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 07/31/2014] [Accepted: 08/08/2014] [Indexed: 12/22/2022]
Abstract
The composition of the oral microbiome differs from one intraoral site to another, reflecting in part the host response and immune capacity at each site. By focusing on two major oral infections, periodontal disease and caries, new principles of disease emerge. Periodontal disease affects the soft tissues and bone that support the teeth. Caries is a unique infection of the dental hard tissues. The initiation of both diseases is marked by an increase in the complexity of the microbiome. In periodontitis, pathobionts and keystone pathogens such as Porphyromonas gingivalis appear in greater proportion than in health. As a keystone pathogen, P. gingivalis impairs host immune responses and appears necessary but not sufficient to cause periodontitis. Historically, dental caries had been causally linked to Streptococcus mutans. Contemporary microbiome studies now indicate that singular pathogens are not obvious in either caries or periodontitis. Both diseases appear to result from a perturbation among relatively minor constituents in local microbial communities resulting in dysbiosis. Emergent consortia of the minor members of the respective microbiomes act synergistically to stress the ability of the host to respond and protect. In periodontal disease, host protection first occurs at the level of innate gingival epithelial immunity. Secretory IgA antibody and other salivary antimicrobial systems also act against periodontopathic and cariogenic consortia. When the gingival immune response is impaired, periodontal tissue pathology results when matrix metalloproteinases are released from neutrophils and T cells mediate alveolar bone loss. In caries, several species are acidogenic and aciduric and appear to work synergistically to promote demineralization of the enamel and dentin. Whereas technically possible, particularly for caries, vaccines are unlikely to be commercialized in the near future because of the low morbidity of caries and periodontitis.
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Affiliation(s)
- Massimo Costalonga
- Division of Periodontology, Department of Developmental and Surgical Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, United States.
| | - Mark C Herzberg
- Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, United States; Mucosal and Vaccine Research Center, Minneapolis VA Medical Center, Minneapolis, MN 55417, United States
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Chung KJ, Mitroulis I, Wiessner JR, Zheng YY, Siegert G, Sperandio M, Chavakis T. A novel pathway of rapid TLR-triggered activation of integrin-dependent leukocyte adhesion that requires Rap1 GTPase. Mol Biol Cell 2014; 25:2948-55. [PMID: 25057020 PMCID: PMC4230584 DOI: 10.1091/mbc.e14-04-0867] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
TLR2 and TLR5 ligation directly induces β2-integrin activation, promoting cell adhesion to ICAM-1. Systemic in vivo administration of the TLR2 ligand Pam3CSK4 increases integrin-dependent adhesion to endothelium within minutes. The signaling pathway linking TLR ligation with β2-integin activation involves Rac-1, NADPH oxidase 2, and Rap1-GTPase. Rapid β2-integrin activation is indispensable for leukocyte adhesion and recruitment to sites of infection and is mediated by chemokine- or P-selectin glycoprotein ligand-1–induced inside-out signaling. Here we uncovered a novel pathway for rapid activation of integrin-dependent leukocyte adhesion, triggered by toll-like receptor (TLR)–mediated signaling. TLR2 or TLR5 ligation rapidly activated integrin-dependent leukocyte adhesion to immobilized ICAM-1 and fibronectin. Consistently, in vivo administration of the TLR2-ligand Pam3CSK4 increased integrin-dependent slow rolling and adhesion to endothelium within minutes, as identified by intravital microscopy in the cremaster model. TLR2 and TLR5 ligation increased β2-integrin affinity, as assessed by the detection of activation-dependent neoepitopes. TLR2- and TLR5-triggered integrin activation in leukocytes required enhanced Rap1 GTPase activity, which was mediated by Rac1 activation and NADPH oxidase-2–dependent reactive oxygen species production. This novel direct pathway linking initial pathogen recognition by TLRs to rapid β2-integrin activation may critically regulate acute leukocyte infiltration to sites of pathogen invasion.
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Affiliation(s)
- Kyoung-Jin Chung
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, 01309 Dresden, Germany Institute of Physiology, Technische Universität Dresden, 01309 Dresden, Germany
| | - Ioannis Mitroulis
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, 01309 Dresden, Germany Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01309 Dresden, Germany
| | - Johannes R Wiessner
- Walter Brendel Center of Experimental Medicine, Ludwig-Maximilians Universität, 80539 Munich, Germany
| | - Ying Yi Zheng
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL 32610
| | - Gabriele Siegert
- Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01309 Dresden, Germany
| | - Markus Sperandio
- Walter Brendel Center of Experimental Medicine, Ludwig-Maximilians Universität, 80539 Munich, Germany
| | - Triantafyllos Chavakis
- Department of Clinical Pathobiochemistry, Technische Universität Dresden, 01309 Dresden, Germany Institute of Physiology, Technische Universität Dresden, 01309 Dresden, Germany Institute for Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, 01309 Dresden, Germany Department of Medicine III, Technische Universität Dresden, 01309 Dresden, Germany
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Hajishengallis G, Lamont RJ. Breaking bad: manipulation of the host response by Porphyromonas gingivalis. Eur J Immunol 2014; 44:328-38. [PMID: 24338806 DOI: 10.1002/eji.201344202] [Citation(s) in RCA: 214] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 12/02/2013] [Accepted: 12/09/2013] [Indexed: 02/06/2023]
Abstract
Recent metagenomic and mechanistic studies are consistent with a new model of periodontal pathogenesis. This model proposes that periodontal disease is initiated by a synergistic and dysbiotic microbial community rather than by a select few bacteria traditionally known as "periopathogens." Low-abundance bacteria with community-wide effects that are critical for the development of dysbiosis are now known as keystone pathogens, the best-documented example of which is Porphyromonas gingivalis. Here, we review established mechanisms by which P. gingivalis interferes with host immunity and enables the emergence of dysbiotic communities. We integrate the role of P. gingivalis with that of other bacteria acting upstream and downstream in pathogenesis. Accessory pathogens act upstream to facilitate P. gingivalis colonization and co-ordinate metabolic activities, whereas commensals-turned pathobionts act downstream and contribute to destructive inflammation. The recent concepts of keystone pathogens, along with polymicrobial synergy and dysbiosis, have profound implications for the development of therapeutic options for periodontal disease.
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Affiliation(s)
- George Hajishengallis
- Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Lam HM, Ouyang B, Chen J, Ying J, Wang J, Wu CL, Li J, Medvedovic M, Vessella RL, Ho SM. Targeting GPR30 with G-1: a new therapeutic target for castration-resistant prostate cancer. Endocr Relat Cancer 2014; 21:903-14. [PMID: 25287069 PMCID: PMC4233119 DOI: 10.1530/erc-14-0402] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Castration-resistant prostate cancer (CRPC) is an advanced-stage prostate cancer (PC) associated with high mortality. We reported that G-1, a selective agonist of G protein-coupled receptor 30 (GPR30), inhibited PC cell growth by inducing G2 cell cycle arrest and arrested PC-3 xenograft growth. However, the therapeutic actions of G-1 and their relationships with androgen in vivo are unclear. Using the LNCaP xenograft to model PC growth during the androgen-sensitive (AS) versus the castration-resistant (CR) phase, we found that G-1 inhibited growth of CR but not AS tumors with no observable toxicity to the host. Substantial necrosis (approximately 65%) accompanied by marked intratumoral infiltration of neutrophils was observed only in CR tumors. Global transcriptome profiling of human genes identified 99 differentially expressed genes with 'interplay between innate and adaptive immune responses' as the top pathway. Quantitative PCR confirmed upregulation of neutrophil-related chemokines and inflammation-mediated cytokines only in the G-1-treated CR tumors. Expression of murine neutrophil-related cytokines also was elevated in these tumors. GPR30 (GPER1) expression was significantly higher in CR tumors than in AS tumors. In cell-based experiments, androgen repressed GPR30 expression, a response reversible by anti-androgen or siRNA-induced androgen receptor silencing. Finally, in clinical specimens, 80% of CRPC metastases (n=123) expressed a high level of GPR30, whereas only 54% of the primary PCs (n=232) showed high GPR30 expression. Together, these results provide the first evidence, to our knowledge, that GPR30 is an androgen-repressed target and G-1 mediates the anti-tumor effect via neutrophil-infiltration-associated necrosis in CRPC. Additional studies are warranted to firmly establish GPR30 as a therapeutic target in CRPC.
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MESH Headings
- Androgens/pharmacology
- Animals
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Blotting, Western
- Cell Proliferation/drug effects
- Chromatin Immunoprecipitation
- Cohort Studies
- Cyclopentanes/pharmacology
- Follow-Up Studies
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic/drug effects
- Humans
- Immunoenzyme Techniques
- Male
- Mice
- Neoplasm Metastasis
- Neoplasm Staging
- Prognosis
- Prostatic Neoplasms, Castration-Resistant/drug therapy
- Prostatic Neoplasms, Castration-Resistant/metabolism
- Prostatic Neoplasms, Castration-Resistant/pathology
- Quinolines/pharmacology
- RNA, Messenger/genetics
- RNA, Small Interfering/genetics
- Real-Time Polymerase Chain Reaction
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Receptors, Estrogen/antagonists & inhibitors
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Receptors, G-Protein-Coupled/antagonists & inhibitors
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Tumor Cells, Cultured
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Hung-Ming Lam
- Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH
| | - Bin Ouyang
- Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH
| | - Jing Chen
- Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH
| | - Jun Ying
- Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH
| | - Jiang Wang
- Department of Pathology and Laboratory Medicine, University of Cincinnati Medical Center, Cincinnati, OH
| | - Chin-Lee Wu
- Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Jia Li
- Department of Medicine, Center for Pharmacogenomics, Washington University School of Medicine, St. Louis, MO
| | - Mario Medvedovic
- Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH
- Center for Environmental Genetics, University of Cincinnati Medical Center, Cincinnati, OH
| | | | - Shuk-Mei Ho
- Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH
- Center for Environmental Genetics, University of Cincinnati Medical Center, Cincinnati, OH
- Cincinnati Veterans Affairs Medical Center, Cincinnati, OH
- Cincinnati Cancer Center, Cincinnati, OH
- Corresponding author: Shuk-Mei Ho, Room 128 Kettering Complex, Department of Environmental Health, University of Cincinnati Medical Center, Cincinnati, OH 45267-0056, USA. Tel: 513-558-5701, Fax: 513-558-4397,
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Nagano K. FimA Fimbriae of the Periodontal Disease-associated Bacterium Porphyromonas gingivalis. YAKUGAKU ZASSHI 2013; 133:963-74. [DOI: 10.1248/yakushi.13-00177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Keiji Nagano
- Department of Microbiology, School of Dentistry, Aichi Gakuin University
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35
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Hypermethylation and low transcription of TLR2 gene in chronic periodontitis. Hum Immunol 2013; 74:1231-6. [PMID: 23747679 DOI: 10.1016/j.humimm.2013.04.037] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 02/06/2013] [Accepted: 04/23/2013] [Indexed: 11/20/2022]
Abstract
Periodontitis is an inflammatory disorder characterized by interactions between periodontal pathogens and host's immune response. Epigenetic may contribute to disease development and outcome by influencing the expression of genes involved in the immune response. It has been shown that Toll-like receptors (TLR) play an important role in the response to periodontopathic bacteria. The aim of study was to evaluate the methylation status and the expression of TLR2 gene in gingival samples from individuals with and without periodontitis. DNA was analyzed using the Methyl Profiler DNA Methylation qPCR assay. DNA methylation and transcript levels were evaluated by real-time polymerase chain reaction. The periodontitis group showed a hypermethylated profile and a low expression of gene. Positive correlation between the TLR2 methylation frequency and probing depth was observed. This study gives the first evidence of methylation frequency in inflamed periodontal tissues and of the possible participation of methylation in the development of periodontitis.
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Hajishengallis G, Lambris JD. Complement and dysbiosis in periodontal disease. Immunobiology 2013; 217:1111-6. [PMID: 22964237 DOI: 10.1016/j.imbio.2012.07.007] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2012] [Revised: 07/13/2012] [Accepted: 07/14/2012] [Indexed: 12/16/2022]
Abstract
Signaling crosstalk between complement and Toll-like receptors (TLRs) normally serves to coordinate host immunity. However, the periodontal bacterium Porphyromonas gingivalis expresses C5 convertase-like enzymatic activity and adeptly exploits complement-TLR crosstalk to subvert host defenses and escape elimination. Intriguingly, this defective immune surveillance leads to the remodeling of the periodontal microbiota to a dysbiotic state that causes inflammatory periodontitis. Understanding the mechanisms by which P. gingivalis modulates complement function to cause dysbiosis offers new targets for complement therapeutics.
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Affiliation(s)
- George Hajishengallis
- University of Pennsylvania School of Dental Medicine, Department of Microbiology, Philadelphia, PA 19104, USA.
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Fine tuning inflammation at the front door: macrophage complement receptor 3-mediates phagocytosis and immune suppression for Francisella tularensis. PLoS Pathog 2013; 9:e1003114. [PMID: 23359218 PMCID: PMC3554622 DOI: 10.1371/journal.ppat.1003114] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 11/19/2012] [Indexed: 12/11/2022] Open
Abstract
Complement receptor 3 (CR3, CD11b/CD18) is a major macrophage phagocytic receptor. The biochemical pathways through which CR3 regulates immunologic responses have not been fully characterized. Francisella tularensis is a remarkably infectious, facultative intracellular pathogen of macrophages that causes tularemia. Early evasion of the host immune response contributes to the virulence of F. tularensis and CR3 is an important receptor for its phagocytosis. Here we confirm that efficient attachment and uptake of the highly virulent Type A F. tularensis spp. tularensis strain Schu S4 by human monocyte-derived macrophages (hMDMs) requires complement C3 opsonization and CR3. However, despite a>40-fold increase in uptake following C3 opsonization, Schu S4 induces limited pro-inflammatory cytokine production compared with non-opsonized Schu S4 and the low virulent F. novicida. This suggests that engagement of CR3 by opsonized Schu S4 contributes specifically to the immune suppression during and shortly following phagocytosis which we demonstrate by CD11b siRNA knockdown in hMDMs. This immune suppression is concomitant with early inhibition of ERK1/2, p38 MAPK and NF-κB activation. Furthermore, TLR2 siRNA knockdown shows that pro-inflammatory cytokine production and MAPK activation in response to non-opsonized Schu S4 depends on TLR2 signaling providing evidence that CR3-TLR2 crosstalk mediates immune suppression for opsonized Schu S4. Deletion of the CD11b cytoplasmic tail reverses the CR3-mediated decrease in ERK and p38 activation during opsonized Schu-S4 infection. The CR3-mediated signaling pathway involved in this immune suppression includes Lyn kinase and Akt activation, and increased MKP-1, which limits TLR2-mediated pro-inflammatory responses. These data indicate that while the highly virulent F. tularensis uses CR3 for efficient uptake, optimal engagement of this receptor down-regulates TLR2-dependent pro-inflammatory responses by inhibiting MAPK activation through outside-in signaling. CR3-linked immune suppression is an important mechanism involved in the pathogenesis of F. tularensis infection.
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Hajishengallis G, McIntosh ML, Nishiyama SI, Yoshimura F. Mechanism and implications of CXCR4-mediated integrin activation by Porphyromonas gingivalis. Mol Oral Microbiol 2013; 28:239-49. [PMID: 23331495 DOI: 10.1111/omi.12021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2012] [Indexed: 12/14/2022]
Abstract
In monocytes and macrophages, the interaction of Porphyromonas gingivalis with Toll-like receptor 2 (TLR2) leads to the activation of a MyD88-dependent antimicrobial pathway and a phosphatidylinositol-3 kinase (PI3K) -dependent pro-adhesive pathway, which activates the β2 -integrin complement receptor 3 (CR3). By means of its fimbriae, P. gingivalis binds CXC-chemokine receptor 4 (CXCR4) and induces crosstalk with TLR2 that inhibits the MyD88-dependent antimicrobial pathway. In this paper, we investigated the impact of the P. gingivalis-CXCR4 interaction on the pro-adhesive pathway. Using human monocytes, mouse macrophages, or receptor-transfected cell lines, we showed that the binding of P. gingivalis fimbriae to CXCR4 induces CR3 activation via PI3K, albeit in a TLR2-independent manner. An isogenic strain of P. gingivalis expressing mutant fimbriae that do not interact with CXCR4 failed to efficiently activate CR3, leading to enhanced susceptibility to killing in vivo compared with the wild-type organism. This in vivo observation is consistent with previous findings that activated CR3 mediates safe entry of P. gingivalis into macrophages. Taken together with our previous work, these results indicate that the interaction of P. gingivalis with CXCR4 leads to inhibition of antimicrobial responses and enhancement of pro-adhesive responses, thereby maximizing its adaptive fitness in the mammalian host.
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Affiliation(s)
- G Hajishengallis
- Department of Microbiology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA.
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Papadopoulos G, Weinberg EO, Massari P, Gibson FC, Wetzler LM, Morgan EF, Genco CA. Macrophage-specific TLR2 signaling mediates pathogen-induced TNF-dependent inflammatory oral bone loss. THE JOURNAL OF IMMUNOLOGY 2012; 190:1148-57. [PMID: 23264656 DOI: 10.4049/jimmunol.1202511] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Porphyromonas gingivalis is a primary etiological agent of chronic periodontal disease, an infection-driven chronic inflammatory disease that leads to the resorption of tooth-supporting alveolar bone. We previously reported that TLR2 is required for P. gingivalis-induced alveolar bone loss in vivo, and our in vitro work implicated TNF as a key downstream mediator. In this study, we show that TNF-deficient (Tnf(-/-)) mice are resistant to alveolar bone loss following oral infection with P. gingivalis, and thus establish a central role for TNF in experimental periodontal disease. Using bone marrow-derived macrophages (BMDM) from wild-type and gene-specific knockout mice, we demonstrate that the initial inflammatory response to P. gingivalis in naive macrophages is MyD88 dependent and requires cooperative signaling of TLR2 and TLR4. The ability of P. gingivalis to activate cells via TLR2 or TLR4 was confirmed in TLR2- or TLR4-transformed human embryonic kidney cells. Additional studies using bacterial mutants demonstrated a role for fimbriae in the modulation of TLR-mediated activation of NF-κB. Whereas both TLR2 and TLR4 contributed to TNF production in naive macrophages, P. gingivalis preferentially exploited TLR2 in endotoxin-tolerant BMDM to trigger excessive TNF production. We found that TNF induced surface TLR2 expression and augmented TLR-induced cytokine production in P. gingivalis-stimulated BMDM, establishing a previously unidentified TNF-dependent feedback loop. Adoptive transfer of TLR2-expressing macrophages to TLR2-deficient mice restored the ability of P. gingivalis to induce alveolar bone loss in vivo. Collectively, our results identify a TLR2- and TNF-dependent macrophage-specific mechanism underlying pathogen-induced inflammatory bone loss in vivo.
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Affiliation(s)
- George Papadopoulos
- Section of Infectious Diseases, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
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40
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CD14 cooperates with complement receptor 3 to mediate MyD88-independent phagocytosis of Borrelia burgdorferi. Proc Natl Acad Sci U S A 2012; 109:1228-32. [PMID: 22232682 DOI: 10.1073/pnas.1112078109] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Phagocytosis of Borrelia burgdorferi, the causative agent of Lyme disease, is a poorly understood process, despite its importance during the host immune response to infection. B. burgdorferi has been shown to bind to different receptors on the surface of phagocytic cells, including the β(2) integrin, complement receptor 3 (CR3). However, whether these receptors mediate the phagocytosis of the spirochete remains unknown. We now demonstrate that CR3 mediates the phagocytosis of the spirochete by murine macrophages and human monocytes. Interaction of B. burgdorferi with the integrin is not sufficient, however, to internalize the spirochete; phagocytosis requires the interaction of CR3 with the GPI-anchored protein, CD14, independently of TLR/MyD88-induced or inside-out signals. Interestingly, the absence of CR3 leads to marked increases in the production of TNF in vitro and in vivo, despite reduced spirochetal uptake. Furthermore, the absence of CR3 during infection with B. burgdorferi results in the inefficient control of bacterial burdens in the heart and increased Lyme carditis. Overall, our data identify CR3 as a MyD88-independent phagocytic receptor for B. burgdorferi that also participates in the modulation of the proinflammatory output of macrophages. These data also establish a unique mechanism of CR3-mediated phagocytosis that requires the direct cooperation of GPI-anchored proteins.
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41
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Pathogenic microbes and community service through manipulation of innate immunity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 946:69-85. [PMID: 21948363 DOI: 10.1007/978-1-4614-0106-3_5] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The periodontal pathogen Porphyromonas gingivalis undermines major components of innate immunity, such as complement, Toll-like receptors (TLR), and their crosstalk pathways. At least in principle, these subversive activities could promote the adaptive fitness of the entire periodontal biofilm community. In this regard, the virulence factors responsible for complement and TLR exploitation (gingipain enzymes, atypical lipopolysaccharide molecules, and fimbriae) are released as components of readily diffusible membrane vesicles, which can thus become available to other biofilm organisms. This review summarizes important immune subversive tactics of P. gingivalis which might enable it to exert a supportive impact on the oral microbial community.
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42
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Batsford S, Dunn J, Mihatsch M. Induction of Experimental Arthritis by Borrelial Lipoprotein and CpG Motifs: Are Toll-Like Receptors 2, 4, 9 or CD-14 Involved? Open Rheumatol J 2011; 5:18-23. [PMID: 21804904 PMCID: PMC3141342 DOI: 10.2174/1874312901105010018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 05/02/2011] [Accepted: 05/13/2011] [Indexed: 12/22/2022] Open
Abstract
Bacterial lipoproteins and CpG-DNA are ligands for Toll-Like-Receptors (TLR) 2 and 9 respectively. Both classes of molecules were reported to induce experimental arthritis in rodents following direct intra-articular injection. Here we studied: 1) whether arthritis induction by Outer surface (Lipo)protein A (OspA) (B.burgdorferi) involved the TLR-2 as well as the TLR-4 or the CD-14 receptors in addition, and 2) re-examined the arthritogenic potential of CpG-DNA motifs in mice. Following intra-articular injection of the test substances [20µg recombinant, lipidated OspA; 1nM(6µg) to 10nM(60µg) synthetic CpG-DNA], inflammation was monitored by 99Tc scintigraphy (ratio left/right knee joint uptake > 1.1 indicates inflammation) and by histology. Lipoprotein OspA induced severe, acute arthritis in TLR-2+/+ w.t. but not in TLR-2-/- mice (p<0.01). There were no significant differences in the severity of arthritis induced in TLR-4+/+ w.t. and TLR-4-/- mutant mice, or between CD14+/+ w.t. and CD14-/- mice. CpG-DNA (1or 10 nM) did not cause notable inflammation in C57BL/6 mice; 99Tc ratios were < 1.0 and histology showed only minimal changes. Induction of arthritis by the OspA lipoprotein of B.burgdorferi involves the TLR-2 receptor, no evidence for additional participation of TLR-4 or CD14 receptors was found. Intra-articular injection of CpG-DNA did not produce manifest joint injury in mice, at variance with previous reports.
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Affiliation(s)
- Stephen Batsford
- Department of Immunology, Institute of Medical Microbiology and Hygiene, Albert Ludwigs University Freiburg, D-79104 Germany
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Hajishengallis G, Lambris JD. Microbial manipulation of receptor crosstalk in innate immunity. Nat Rev Immunol 2011; 11:187-200. [PMID: 21350579 DOI: 10.1038/nri2918] [Citation(s) in RCA: 222] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the arms race of host-microbe co-evolution, successful microbial pathogens have evolved ingenious ways to evade host immune responses. In this Review, we focus on 'crosstalk manipulation' - the microbial strategies that instigate, subvert or disrupt the molecular signalling crosstalk between receptors of the innate immune system. This proactive interference undermines host defences and contributes to microbial adaptive fitness and persistent infections. Understanding how pathogens exploit host receptor crosstalk mechanisms and infiltrate the host signalling network is essential for developing interventions to redirect the host response and achieve protective immunity.
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Affiliation(s)
- George Hajishengallis
- University of Louisville, Department of Microbiology and Immunology, Louisville, Kentucky 40292, USA.
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Alvarez Y, Municio C, Hugo E, Zhu J, Alonso S, Hu X, Fernández N, Sánchez Crespo M. Notch- and transducin-like enhancer of split (TLE)-dependent histone deacetylation explain interleukin 12 (IL-12) p70 inhibition by zymosan. J Biol Chem 2011; 286:16583-95. [PMID: 21402701 DOI: 10.1074/jbc.m111.222158] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The fungal analog zymosan induces IL-23 and low amounts of IL-12 p70. This study addresses the molecular mechanisms underlying this cytokine pattern in human monocyte-derived dendritic cells. The transcriptional regulation of il23a, one of the chains of IL-23, depended on the activation of c-Rel and histone H3 phosphorylation, as judged from the association of c-Rel with the il23a promoter and the correlation between IL-23 production and Ser-10-histone H3 phosphorylation. Consistent with its reduced ability to produce IL-12 p70, zymosan induced a transient occupancy of the il12a promoter by c-Rel, blocked the production of IL-12 p70 and the transcription of il12a induced by other stimuli, and triggered the expression and nuclear translocation of the transcriptional repressors of the Notch family hairy and enhancer of split (Hes)-1, Hes5, hairy/enhancer-of-split related with YRPW motif protein (Hey)-1, and transducin-like enhancer of split (TLE). Zymosan also induced the interaction of Hes1 and TLE with histone H3 phosphorylated on Ser-10 and deacetylated on Lys-14. Inhibition of class III histone deacetylases increased the production of IL-12 p70 and partially blunted the inhibitory effect of zymosan on the production of IL-12 p70 elicited by LPS and IFN-γ. These results indicate that the selective induction of IL-23 by β-glucans is explained by the activation of c-Rel associated with Ser-10-histone H3 phosphorylation in the il23a promoter mediated by mitogen- and stress-activated kinase and/or protein kinase A and inhibition of il12a transcription by a mechanism involving activation of several corepressors with the ability to bind TLE and to promote histone deacetylation.
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Affiliation(s)
- Yolanda Alvarez
- Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas, 47003-Valladolid, Spain
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Lipoxin A₄ inhibits porphyromonas gingivalis-induced aggregation and reactive oxygen species production by modulating neutrophil-platelet interaction and CD11b expression. Infect Immun 2011; 79:1489-97. [PMID: 21263017 DOI: 10.1128/iai.00777-10] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Porphyromonas gingivalis is an etiological agent that is strongly associated with periodontal disease, and it correlates with numerous inflammatory disorders, such as cardiovascular disease. Circulating bacteria may contribute to atherogenesis by promoting CD11b/CD18-mediated interactions between neutrophils and platelets, causing reactive oxygen species (ROS) production and aggregation. Lipoxin A₄ (LXA₄) is an endogenous anti-inflammatory and proresolving mediator that is protective of inflammatory disorders. The aim of this study was to investigate the effect of LXA₄ on the P. gingivalis-induced activation of neutrophils and platelets and the possible involvement of Rho GTPases and CD11b/CD18 integrins. Platelet/leukocyte aggregation and ROS production was examined by lumiaggregometry and fluorescence microscopy. Integrin activity was studied by flow cytometry, detecting the surface expression of CD11b/CD18 as well as the exposure of the high-affinity integrin epitope, whereas the activation of Rac2/Cdc42 was examined using a glutathione S-transferase pulldown assay. The study shows that P. gingivalis activates Rac2 and Cdc42 and upregulates CD11b/CD18 and its high-affinity epitope on neutrophils, and that these effects are diminished by LXA₄. Furthermore, we found that LXA₄ significantly inhibits P. gingivalis-induced aggregation and ROS generation in whole blood. However, in platelet-depleted blood and in isolated neutrophils and platelets, LXA₄ was unable to inhibit either aggregation or ROS production, respectively. In conclusion, this study suggests that LXA₄ antagonizes P. gingivalis-induced cell activation in a manner that is dependent on leukocyte-platelet interaction, likely via the inhibition of Rho GTPase signaling and the downregulation of CD11b/CD18. These findings may contribute to new strategies in the prevention and treatment of periodontitis-induced inflammatory disorders, such as atherosclerosis.
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Brown J, Wang H, Hajishengallis GN, Martin M. TLR-signaling networks: an integration of adaptor molecules, kinases, and cross-talk. J Dent Res 2010; 90:417-27. [PMID: 20940366 DOI: 10.1177/0022034510381264] [Citation(s) in RCA: 411] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED Toll-like receptors play a critical role in innate immunity by detecting invading pathogens. The ability of TLRs to engage different intracellular signaling molecules and cross-talk with other regulatory pathways is an important factor in shaping the type, magnitude, and duration of the inflammatory response. The present review will cover the fundamental signaling pathways utilized by TLRs and how these pathways regulate the innate immune response to pathogens. ABBREVIATIONS TLR, Toll-like receptor; PRR, pattern recognition receptor; PAMP, pathogen-associated molecular pattern; LPS, lipopolysaccharide; APC, antigen-presenting cell; IL, interleukin; TIR, Toll/IL-1R homology; MyD88, myeloid differentiation factor 88; IFN, interferon; TRIF, TIR-domain-containing adapter-inducing interferon-β; IRAK, IL-1R-associated kinase; TAK1, TGF-β-activated kinase; TAB1, TAK1-binding protein; NF-κB, nuclear factor kappa-light-chain-enhancer of activated B-cells; MAPK, mitogen-activated protein kinase; NLR, NOD-like receptors; LRR, leucine-rich repeats; DC, dendritic cell; PI3K, phosphoinositide 3-kinases; GSK3, glycogen synthase kinase-3; mTOR, mammalian target of rapamycin; DAF, decay-accelerating factor; IKK, IκB kinase; IRF, interferon regulatory factors; TBK1, TANK-binding kinase 1; CARD, caspase activation and recruitment domain; PYD, pyrin N-terminal homology domain; ATF, activating transcription factor; and PTEN, phosphatase and tensin homolog.
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Affiliation(s)
- J Brown
- Department of Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, KY 40202, USA
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Sun Y, Shu R, Li CL, Zhang MZ. Gram-Negative Periodontal Bacteria Induce the Activation of Toll-Like Receptors 2 and 4, and Cytokine Production in Human Periodontal Ligament Cells. J Periodontol 2010; 81:1488-96. [DOI: 10.1902/jop.2010.100004] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Kebschull M, Demmer RT, Papapanou PN. "Gum bug, leave my heart alone!"--epidemiologic and mechanistic evidence linking periodontal infections and atherosclerosis. J Dent Res 2010; 89:879-902. [PMID: 20639510 DOI: 10.1177/0022034510375281] [Citation(s) in RCA: 319] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Evidence from epidemiologic studies suggests that periodontal infections are independently associated with subclinical and clinical atherosclerotic vascular disease. Although the strength of the reported associations is modest, the consistency of the data across diverse populations and a variety of exposure and outcome variables suggests that the findings are not spurious or attributable only to the effects of confounders. Analysis of limited data from interventional studies suggests that periodontal treatment generally results in favorable effects on subclinical markers of atherosclerosis, although such analysis also indicates considerable heterogeneity in responses. Experimental mechanistic in vitro and in vivo studies have established the plausibility of a link between periodontal infections and atherogenesis, and have identified biological pathways by which these effects may be mediated. However, the utilized models are mostly mono-infections of host cells by a limited number of 'model' periodontal pathogens, and therefore may not adequately portray human periodontitis as a polymicrobial, biofilm-mediated disease. Future research must identify in vivo pathways in humans that may (i) lead to periodontitis-induced atherogenesis, or (ii) result in treatment-induced reduction of atherosclerosis risk. Data from these studies will be essential for determining whether periodontal interventions have a role in the primary or secondary prevention of atherosclerosis.
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Affiliation(s)
- M Kebschull
- Division of Periodontics, Section of Oral and Diagnostic Sciences, College of Dental Medicine, 630 W 168th Street, PH-7-E-110, New York, NY 10032, USA
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Analysis of immunostimulatory activity of Porphyromonas gingivalis fimbriae conferred by Toll-like receptor 2. Biochem Biophys Res Commun 2010; 398:86-91. [DOI: 10.1016/j.bbrc.2010.06.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2010] [Accepted: 06/09/2010] [Indexed: 11/18/2022]
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