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Abstract
BACKGROUND The process of extravasation of leucocytes from the vasculature into an infected, inflamed or injured tissue, designated the leucocyte adhesion cascade, is a major process in innate and adaptive immunity. In every immune process, both agonists and inhibitors, that is, positive and negative regulators, exist. MATERIALS AND METHODS It was only recently that endogenous inhibitors of the leucocyte adhesion cascade were identified, whereas many selectin, integrin and immunoglobulin superfamily adhesion receptors as well as chemokines and chemokine receptors promoting leucocyte recruitment have been described over the last three decades. Endogenous negative regulators include for instance pentraxin-3 (PTX-3) that blocks selectin-dependent leucocyte rolling, or the endothelium-derived developmental endothelial locus-1 (Del-1) that antagonizes beta2-integrin-mediated firm adhesion of leucocytes to the endothelium. CONCLUSIONS As leucocyte infiltration is a major therapeutic target in inflammatory and autoimmune disease, it becomes obvious that such endogenous anti-adhesive and anti-inflammatory agents may represent an attractive novel therapeutic platform for inflammatory and immune disorders. This review focuses on these novel endogenous inhibitors of leucocyte recruitment.
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Affiliation(s)
- Triantafyllos Chavakis
- Division of Vascular Inflammation, Diabetes and Kidney, Department of Medicine and Institute of Physiology, University Dresden, Dresden, Germany.
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2
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de Gouw D, Diavatopoulos DA, Bootsma HJ, Hermans PW, Mooi FR. Pertussis: a matter of immune modulation. FEMS Microbiol Rev 2011; 35:441-74. [DOI: 10.1111/j.1574-6976.2010.00257.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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3
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Chavakis E, Choi EY, Chavakis T. Novel aspects in the regulation of the leukocyte adhesion cascade. Thromb Haemost 2009; 102:191-7. [PMID: 19652868 DOI: 10.1160/th08-12-0844] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Leukocyte recruitment plays a major role in the immune response to infectious pathogens and during inflammatory and autoimmune disorders. The process of leukocyte extravasation from the blood into the inflamed tissue requires a complex cascade of adhesive events between the leukocytes and the endothelium including leukocyte rolling, adhesion and transendothelial migration. Leukocyte-endothelial interactions are mediated by tightly regulated binding interactions between adhesion receptors on both cells. In this regard, leukocyte adhesion onto the endothelium is governed by leukocyte integrins and their endothelial counter-receptors of the immunoglobulin superfamily. The present review will focus on novel aspects with respect to the modulation of the leukocyte adhesion cascade.
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4
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Tagawa Y, Sanders JD, Uchida I, Bastida-Corcuera FD, Kawashima K, Corbeil LB. Genetic and functional analysis of Haemophilus somnus high molecular weight-immunoglobulin binding proteins. Microb Pathog 2005; 39:159-70. [PMID: 16169703 DOI: 10.1016/j.micpath.2005.08.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2005] [Accepted: 08/03/2005] [Indexed: 11/23/2022]
Abstract
Haemophilus somnus immunoglobulin binding proteins (IgBPs) are virulence associated but only one (p76) has been genetically defined. We determined the nucleotide sequence of the 5'-flanking region of the p76 gene. This region had been identified as the coding region for a series of high molecular weight (HMW)-IgBPs. Analysis of the nucleotide sequence indicated the gene (immunoglobulin binding protein A, ibpA) encoding the HMW and p76 IgBPs comprised a single open reading frame of 12,285 base pairs (bp). The ibpA gene is flanked by an upstream ORF of 1758bp, designated ibpB. The predicted amino acid sequences of these two genes demonstrate similarity to virulence exoproteins and their transporter proteins that comprise a two-partner secretion pathway in various Gram-negative bacteria. Motifs associated with binding to mammalian cells were also identified within the sequence. Competitive inhibition studies implicated a putative heparin-binding domain in adherence to bovine endothelial cells. Expression plasmids for glutathione S-transferase (GST)-fused recombinant fragments covered amino acid residues 972-3201. IgG2 Fc binding studies identified fragment 972-1515 (GST-IbpA3) as an Fc binding peptide. This peptide and GST-IbpA5 (aa 2071-2730) reacted strongly with convalescent phase serum. In a small preliminary study, calves immunized with the purified GST-IbpA3 peptide were protected against an intrabronchial H. somnus challenge.
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Affiliation(s)
- Yuichi Tagawa
- Department of Pathology, University of California, San Diego Medical Center, 200 West Arbor Drive, San Diego, CA 92103-8416, USA.
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5
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Ohman L, Willén R, Hultgren OH, Hultgren Hörnquist E. Acellular Bordetella pertussis vaccine enhances mucosal interleukin-10 production, induces apoptosis of activated Th1 cells and attenuates colitis in Galphai2-deficient mice. Clin Exp Immunol 2005; 141:37-46. [PMID: 15958068 PMCID: PMC1809410 DOI: 10.1111/j.1365-2249.2005.02807.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Mice deficient for the inhibitory G protein subunit alpha2 (Galphai2(-/-)) spontaneously develop a progressive inflammatory bowel disease resembling ulcerative colitis, and have a T helper 1 (Th1)-dominated immune response prior to onset of colitis, which is further augmented after the onset of disease. The present study was performed to investigate whether the Galphai2(-/-) mice were able to down-regulate the Th1-dominated inflammatory mucosal immune response and/or induce an anti-inflammatory Th2/T regulatory response and thereby diminish the severity of colitis following treatment with acellular Bordetella pertussis vaccine. The acellular vaccine against B. pertussis, the causative agent of whooping cough, has been demonstrated to induce a Th2-mediated response in both man and mice. We therefore treated Galphai2(-/-) mice intraperitoneally with a three-component acellular B. pertussis vaccine. The treated Galphai2(-/-) mice showed significantly increased interleukin (IL)-10 production in intestinal tissue, associated with significantly reduced colitis and decreased mortality, compared to untreated Galphai2(-/-) mice. The attenuation of colitis in Galphai2(-/-) mice was due, at least partly, to the B. pertussis surface antigen filamentous haemagglutinin (FHA), which almost completely inhibited proliferation of CD4(+) T cells and stimulated apoptosis of activated CD4(+) T helper 1 cells. In conclusion, the three-component acellular B. pertussis vaccine containing filamentous haemagglutinin increases the production of IL-10 in the intestinal mucosa, induces apoptosis of activated Th1 cells and attenuates colitis in Galphai2(-/-) mice.
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MESH Headings
- Adhesins, Bacterial/immunology
- Animals
- Antigens, Bacterial/immunology
- Apoptosis/immunology
- Colitis, Ulcerative/immunology
- Colitis, Ulcerative/pathology
- Colitis, Ulcerative/therapy
- Disease Models, Animal
- GTP-Binding Protein alpha Subunits/deficiency
- Hemagglutinins/immunology
- Immunity, Mucosal
- Immunoglobulin G/blood
- Interleukin-10/biosynthesis
- Lymphocyte Activation
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Pertussis Vaccine/immunology
- Pertussis Vaccine/therapeutic use
- Survival Rate
- Th1 Cells/immunology
- Virulence Factors, Bordetella/immunology
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Affiliation(s)
- L Ohman
- Department of Clinical Immunology, The Sahlgrenska Academy of Göteborg University, Sweden.
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6
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van der Flier M, Coenjaerts FE, Mwinzi PN, Rijkers E, Ruyken M, Scharringa J, Kimpen JLL, Hoepelman AIM, Geelen SPM. Antibody neutralization of vascular endothelial growth factor (VEGF) fails to attenuate vascular permeability and brain edema in experimental pneumococcal meningitis. J Neuroimmunol 2005; 160:170-7. [PMID: 15710470 DOI: 10.1016/j.jneuroim.2004.11.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2004] [Revised: 10/07/2004] [Accepted: 11/24/2004] [Indexed: 11/18/2022]
Abstract
To determine the contribution of vascular endothelial growth factor (VEGF) to cerebral edema formation in bacterial meningitis, we used a VEGF neutralizing antibody to block VEGF in rabbits, following induction of meningitis by intracisternal inoculation with 10(9) heat-killed pneumococci. At 8 h, cerebrospinal fluid (CSF) VEGF was significantly elevated in infected untreated animals, and correlated with CSF white blood cell (WBC) count (r=0.56, P=0.004), and brain water content (r=0.42, P=0.04). Blocking of VEGF did not attenuate brain edema, blood-brain barrier disruption, or CSF pleocytosis. The functional role of VEGF in the pathophysiology of BM remains elusive.
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MESH Headings
- Animals
- Antibodies, Blocking/administration & dosage
- Antibodies, Blocking/pharmacology
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal, Humanized
- Bevacizumab
- Brain Edema/blood
- Brain Edema/cerebrospinal fluid
- Brain Edema/immunology
- Brain Edema/physiopathology
- Capillary Permeability/immunology
- Cell Movement/immunology
- Cisterna Magna
- Female
- Humans
- Injections, Intravenous
- Leukocytes/immunology
- Leukocytes/pathology
- Meningitis, Pneumococcal/blood
- Meningitis, Pneumococcal/cerebrospinal fluid
- Meningitis, Pneumococcal/immunology
- Meningitis, Pneumococcal/physiopathology
- Mice
- Rabbits
- Vascular Endothelial Growth Factor A/antagonists & inhibitors
- Vascular Endothelial Growth Factor A/blood
- Vascular Endothelial Growth Factor A/cerebrospinal fluid
- Vascular Endothelial Growth Factor A/immunology
- Water-Electrolyte Balance
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Affiliation(s)
- M van der Flier
- Wilhelmina Children's Hospital, University Medical Center, Room KE 04.1331, P.O. Box 85090, 3508 AB Utrecht, The Netherlands
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7
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Haggar A, Ehrnfelt C, Holgersson J, Flock JI. The extracellular adherence protein from Staphylococcus aureus inhibits neutrophil binding to endothelial cells. Infect Immun 2004; 72:6164-7. [PMID: 15385525 PMCID: PMC517550 DOI: 10.1128/iai.72.10.6164-6167.2004] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2004] [Revised: 04/23/2004] [Accepted: 06/25/2004] [Indexed: 11/20/2022] Open
Abstract
Extracellular adherence protein (Eap) from Staphylococcus aureus inhibits the adherence of neutrophils to nonstimulated and tumor necrosis factor alpha-stimulated endothelial cells in both static adhesion assays and flow adhesion assays. Consequently, Eap also impaired their transendothelial migration. During an S. aureus infection, Eap may thus serve to reduce inflammation by inhibiting neutrophil adhesion and extravasation.
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Affiliation(s)
- Axana Haggar
- Division of Clinical Bacteriology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden
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8
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van der Flier M, Geelen SPM, Kimpen JLL, Hoepelman IM, Tuomanen EI. Reprogramming the host response in bacterial meningitis: how best to improve outcome? Clin Microbiol Rev 2003; 16:415-29. [PMID: 12857775 PMCID: PMC164224 DOI: 10.1128/cmr.16.3.415-429.2003] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite effective antibiotic therapy, bacterial meningitis is still associated with high morbidity and mortality in both children and adults. Animal studies have shown that the host inflammatory response induced by bacterial products in the subarachnoid space is associated with central nervous system injury. Thus, attenuation of inflammation early in the disease process might improve the outcome. The feasibility of such an approach is demonstrated by the reduction in neurologic sequelae achieved with adjuvant dexamethasone therapy. Increased understanding of the pathways of inflammation and neuronal damage has suggested rational new targets to modulate the host response in bacterial meningitis, but prediction of which agents would be optimal has been difficult. This review compares the future promise of benefit from the use of diverse adjuvant agents. It appears unlikely that inhibition of a single proinflammatory mediator will prove useful in clinical practice, but several avenues to reprogram a wider array of mediators simultaneously are encouraging. Particularly promising are efforts to adjust combinations of cytokines, to inhibit neuronal apoptosis and to enhance brain repair.
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9
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Alverdy JC, Laughlin RS, Wu L. Influence of the critically ill state on host-pathogen interactions within the intestine: gut-derived sepsis redefined. Crit Care Med 2003; 31:598-607. [PMID: 12576972 DOI: 10.1097/01.ccm.0000045576.55937.67] [Citation(s) in RCA: 161] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Severe and prolonged states of catabolic stress have been shown to have profound effects on the intestinal tract microflora and intestinal function. Gut-derived sepsis is a term used to describe a state of systemic inflammation with organ dysfunction after severe catabolic stress hypothesized to be initiated and perpetuated by the intestinal tract microflora. Popular notions of the mechanism of this process have suggested that stress promotes the translocation of intestinal bacteria or their toxins into the systemic compartment resulting in the release of proinflammatory cytokines which participate in the systemic inflammatory response syndrome. This review is an attempt to redefine the mechanism of gut-derived sepsis by focusing on molecular events that result from host-pathogen interactions within the intestinal tract itself. This evidence-based review posits that gut-derived bacteremia, even with potent nosocomial pathogens, is an event of low proinflammatory potential and, itself, is an insufficient stimulus for the systemic inflammatory response and organ failure state typically seen after severe and prolonged catabolic stress. Mechanisms of this apparent paradox are discussed.
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Affiliation(s)
- John C Alverdy
- Department of Surgery, University of Chicago Medical Center, IL 60637, USA.
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10
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Forsyth CB, Mathews HL. Lymphocyte adhesion to Candida albicans. Infect Immun 2002; 70:517-27. [PMID: 11796578 PMCID: PMC127679 DOI: 10.1128/iai.70.2.517-527.2002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2001] [Revised: 07/23/2001] [Accepted: 10/10/2001] [Indexed: 11/20/2022] Open
Abstract
Adherence of lymphocytes to the fungus is the first step in the direct lymphocyte-mediated antifungal effect against Candida albicans. In this study we identified macrophage-1 antigen (Mac-1) (CD11b/CD18, alpha(M)/beta(2)) as the lymphocyte surface structure responsible for the adhesion of activated lymphocytes to the hyphal form of the fungus. Antibodies specific for epitopes of the alpha-subunit (CD11b) and the beta(2)-subunit (CD18) of Mac-1 were shown to completely eliminate lymphocyte adhesion to C. albicans hyphae. Lymphocyte adhesion to C. albicans was also inhibited significantly by known ligands of Mac-1, including the extracellular matrix proteins laminin and fibrinogen, as well as engineered peptides containing arginine-glycine-aspartic acid sequences and the disintegrin echistatin. N-Acetyl-D-glucosamine and beta-glucan, which inhibit Mac-1-mediated adhesion to the yeast, blocked lymphocyte adhesion to hyphae. NIH 3T3 fibroblast transfectants expressing human CD11b/CD18 bound to C. albicans, and their binding was inhibited by antibodies specific for CD11b/CD18. Finally, antibodies specific for CD11b/CD18 effectively inhibited the capacity of activated lymphocytes to have an antifungal effect against hyphae. Our results clearly identify Mac-1 (CD11b/CD18) as the lymphocyte surface structure that mediates activated lymphocyte adhesion to C. albicans and the resultant antifungal effect of the lymphocytes.
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Affiliation(s)
- Christopher B Forsyth
- Department of Microbiology and Immunology, Loyola University of Chicago, Maywood, Illinois 60153, USA
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11
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Abramson T, Kedem H, Relman DA. Proinflammatory and proapoptotic activities associated with Bordetella pertussis filamentous hemagglutinin. Infect Immun 2001; 69:2650-8. [PMID: 11254631 PMCID: PMC98203 DOI: 10.1128/iai.69.4.2650-2658.2001] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Filamentous hemagglutinin (FHA) is a dominant cell surface-associated Bordetella pertussis adhesin. Recognition that this protein is secreted in significant amounts and that bacterial adhesins may have other activities, prompted an assessment of FHA effects on human macrophages. Incubation of human macrophage-like U937 cells with preparations of FHA resulted in dose-dependent cytotoxicity, with death of 95% of treated cells after 24 h. Based on the use of four independent methods, death of these cells could be largely attributed to apoptosis. FHA-associated apoptosis was also observed in THP-1 macrophage-like cells, fresh human peripheral blood monocyte-derived macrophages (MDM), and BEAS-2B human bronchial epithelial cells. Infection of MDM with wild-type B. pertussis resulted in apoptosis within 6 h, while infection with an FHA-deficient derivative strain was only 50% as effective. FHA-associated cytotoxicity was preceded by host cell secretion of tumor necrosis factor alpha (TNF-alpha), a potential proapoptotic factor. However, pretreatment of cells with a neutralizing anti-TNF-alpha monoclonal antibody inhibited only 16% of the FHA-associated apoptosis. On the other hand, a blocking monoclonal antibody directed against TNF-alpha receptor 1 inhibited FHA-associated apoptosis by 47.7% (P = 0.0001), suggesting that this receptor may play a role in the death pathway activated by FHA. Our in vitro data indicate that secreted and cell-associated FHA elicits proinflammatory and proapoptotic responses in human monocyte-like cells, MDM, and bronchial epithelial cells and suggest a previously unrecognized role for this prominent virulence factor in the B. pertussis-host interaction.
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Affiliation(s)
- T Abramson
- Department of Medicine, Stanford University School of Medicine, Stanford, California 94305, USA
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12
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Tishkoff GH, Hunt LT. Unexpected molecular mimicry among peptides MHC class II, blood-clotting factor X, and HIV-1 envelope glycoprotein GP120. Thromb Res 2000; 98:343-6. [PMID: 10822081 DOI: 10.1016/s0049-3848(99)00245-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- G H Tishkoff
- Department of Medicine, Michigan State University, 48824, East Lansing, MI, USA
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13
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Jacob-Dubuisson F, Kehoe B, Willery E, Reveneau N, Locht C, Relman DA. Molecular characterization of Bordetella bronchiseptica filamentous haemagglutinin and its secretion machinery. MICROBIOLOGY (READING, ENGLAND) 2000; 146 ( Pt 5):1211-1221. [PMID: 10832649 DOI: 10.1099/00221287-146-5-1211] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Two closely related pathogens, Bordetella pertussis and Bordetella bronchiseptica, share a number of virulence factors. Filamentous haemagglutinin (FHA) is widely regarded as the dominant adhesin of B. pertussis, and its multiple binding activities have been well characterized. This large protein is produced and secreted at high levels by B. pertussis and significantly lower levels by B. bronchiseptica strains. FHA secretion is mediated by a single outer-membrane accessory protein, FhaC. The genes encoding FHA and FhaC in B. bronchiseptica were characterized by sequencing and functional analyses and are highly similar to those of B. pertussis. The most distinctive feature of B. bronchiseptica FHA is additional repeats in the N-terminal portion of the predicted protein. Interestingly, a point mutation in the fhaB promoter region of the B. bronchiseptica GP1 isolate, relative to other isolates, was found to be detrimental to promoter activity and to FHA production. FhaC and the N-terminal secretion domain of FHA of B. bronchiseptica were fully functional for secretion in B. pertussis. Thus, the different levels of FHA secretion by these Bordetella species might reflect differences in physiology, composition and structure of cell envelope, or differential protein degradation. Characterization of FHA expression and function may provide clues as to the basis of host species tropism, tissue localization and receptor recognition.
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Affiliation(s)
- Françoise Jacob-Dubuisson
- INSERM U447, Institut de Biologie de Lille1 and Département de Microbiologie des Ecosystèmes, Institut Pasteur de Lille2, 1 rue Calmette, F-59019 Lille Cedex, France
| | - Bettina Kehoe
- VA Palo Alto Health Care System 154T, 3801 Miranda Avenue, Palo Alto, CA 94304, USA4
- Departments of Medicine and Microbiology & Immunology, Stanford University, Stanford, CA 94305, USA3
| | - Eve Willery
- INSERM U447, Institut de Biologie de Lille1 and Département de Microbiologie des Ecosystèmes, Institut Pasteur de Lille2, 1 rue Calmette, F-59019 Lille Cedex, France
| | - Nathalie Reveneau
- INSERM U447, Institut de Biologie de Lille1 and Département de Microbiologie des Ecosystèmes, Institut Pasteur de Lille2, 1 rue Calmette, F-59019 Lille Cedex, France
| | - Camille Locht
- INSERM U447, Institut de Biologie de Lille1 and Département de Microbiologie des Ecosystèmes, Institut Pasteur de Lille2, 1 rue Calmette, F-59019 Lille Cedex, France
| | - David A Relman
- VA Palo Alto Health Care System 154T, 3801 Miranda Avenue, Palo Alto, CA 94304, USA4
- Departments of Medicine and Microbiology & Immunology, Stanford University, Stanford, CA 94305, USA3
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14
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Parent C, Eichacker PQ. Neutrophil and endothelial cell interactions in sepsis. The role of adhesion molecules. Infect Dis Clin North Am 1999; 13:427-47, x. [PMID: 10340176 DOI: 10.1016/s0891-5520(05)70084-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Although adhesion molecules present on circulating neutrophils and endothelial cells are essential for normal host defense, generalized activation of these molecules has been implicated in the inflammatory tissue injury occurring during sepsis and septic shock. A review of both preclinical and clinical studies suggests, however, that although these molecules mediate tissue injury related to a variety of microbial and host inflammatory mediators, their predominant role during sepsis with infection is a protective one.
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Affiliation(s)
- C Parent
- Critical Care Medicine Department, National Institutes of Health, Bethesda, Maryland, USA
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15
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Schnitzler N, Haase G, Podbielski A, Lütticken R, Schweizer KG. A co-stimulatory signal through ICAM-beta2 integrin-binding potentiates neutrophil phagocytosis. Nat Med 1999; 5:231-5. [PMID: 9930874 DOI: 10.1038/5597] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The beta2 integrin LFA-1 (lymphocyte function associated antigen; CD11a/CD18) is the common ligand for the intercellular adhesion molecules (ICAMs). Integrins support cell function by providing co-stimulatory second signals that are a precondition for full cell activation first described for ICAM-1-binding to LFA-1 in lymphocytes. Integrins can also serve to activate functions associated with distinct subunits of other integrins. In addition to LFA-1, neutrophils express the beta2 integrin Mac-1 (CD11b/CD18; CR3) that apparently contains multiple sites that bind invading microbes directly or through surface-fixed C3, resulting in activation of the phagocyte function. Expression of the LFA-1 counter-receptor ICAM-1 on endothelial cells occurs only at the site of inflammation. Therefore, in neutrophils, ICAM-1 ligand binding could, as with lymphocytes, also play a part as a co-stimulatory signal to induce full phagocytotic function. We show that in neutrophils, the LFA-1 ligand interaction is the stimulatory signal to express full phagocytotic activation. This is best demonstrated by the rapid association of Streptococcus pyogenes with neutrophils, followed by ingestion, strong oxidative-burst induction and enhanced killing of these bacteria, which are well-known for their resistance to human neutrophil defense. These findings may contribute to the development of therapeutic strategies targeting the modulation of ICAM-1-leukocyte interaction.
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Affiliation(s)
- N Schnitzler
- Institute of Medical Immunology, National Reference Center for Streptococci, University Hospital, RWTH Aachen, Germany
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16
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Wilson DR, Siebers A, Finlay BB. Antigenic analysis of Bordetella pertussis filamentous hemagglutinin with phage display libraries and rabbit anti-filamentous hemagglutinin polyclonal antibodies. Infect Immun 1998; 66:4884-94. [PMID: 9746593 PMCID: PMC108604 DOI: 10.1128/iai.66.10.4884-4894.1998] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/1998] [Accepted: 07/24/1998] [Indexed: 11/20/2022] Open
Abstract
Although substantial advancements have been made in the development of efficacious acellular vaccines against Bordetella pertussis, continued progress requires better understanding of the antigenic makeup of B. pertussis virulence factors, including filamentous hemagglutinin (FHA). To identify antigenic regions of FHA, phage display libraries constructed by using random fragments of the 10-kbp EcoRI fragment of B. pertussis fhaB were affinity selected with rabbit anti-FHA polyclonal antibodies. Characterization of antibody-reactive clones displaying FHA-derived peptides identified 14 antigenic regions, each containing one or more epitopes. A number of clones mapped within regions containing known or putative FHA adhesin domains and may be relevant for the generation of protective antibodies. The immunogenic potential of the phage-displayed peptides was assessed indirectly by comparing their recognition by antibodies elicited by sodium dodecyl sulfate (SDS)-denatured and native FHA and by measuring the inhibition of this recognition by purified FHA. FHA residues 1929 to 2019 may contain the most dominant linear epitope of FHA. Clones mapping to this region accounted for ca. 20% of clones recovered from the initial library selection and screening procedures. They are strongly recognized by sera against both SDS-denatured and native FHA, and this recognition is readily inhibited by purified FHA. Given also that this region includes a factor X homolog (J. Sandros and E. Tuomanen, Trends Microbiol. 1:192-196, 1993) and that the single FHA epitope (residues 2001 to 2015) was unequivocally defined in a comparable study by E. Leininger et al. (J. Infect. Dis. 175:1423-1431, 1997), peptides derived from residues of 1929 to 2019 of FHA are strong candidates for future protection studies.
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Affiliation(s)
- D R Wilson
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
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17
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Feng Y, Chung D, Garrard L, McEnroe G, Lim D, Scardina J, McFadden K, Guzzetta A, Lam A, Abraham J, Liu D, Endemann G. Peptides derived from the complementarity-determining regions of anti-Mac-1 antibodies block intercellular adhesion molecule-1 interaction with Mac-1. J Biol Chem 1998; 273:5625-30. [PMID: 9488691 DOI: 10.1074/jbc.273.10.5625] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Peptides or small molecules that can block the interaction of the integrin Mac-1 with its receptor, intercellular adhesion molecule-1 (ICAM-1), have not previously been developed. We studied this interaction by measuring the adherence of ICAM-1-expressing Chinese hamster ovary (CHO) cells to immobilized, purified Mac-1. Nucleotide sequence information was obtained for the complementarity determining regions (CDRs) of three antibodies (44aacb, MY904, and 118.1) shown to block Mac-1-mediated cell adherence. Peptides were synthesized based on the predicted amino acid sequences of the CDRs and tested for the ability to block cell adhesion to Mac-1. Peptides derived from CDR1 of 44aacb, CDR2 of 118.1, and CDRs 1 and 3 of MY904 heavy chains were found to possess blocking activity at 10-100 muM. This may indicate that one or two CDRs contribute disproportionately to the antibody binding affinity. The binding of ligands to Mac-1 has been shown to require a region of the alpha-chain known as the I- or A-domain. We have recombinantly produced Mac-1 I-domain, and show that it is also capable of supporting the adherence of ICAM-1-expressing CHO cells. The adherence of ICAM-1-CHO cells to the I-domain is inhibited by 44aacb and 118.1 and by the CDR peptides from 44aacb and 118.1. By using phage display of peptide libraries based on the 118.1 CDR peptide with five residues randomized, we were able to identify a novel peptide inhibitor of Mac-1 with substitutions at all five positions. These peptides provide lead structures for development of Mac-1 antagonists.
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Affiliation(s)
- Y Feng
- Scios Inc., Sunnyvale, California 94086, USA
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18
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Mesri M, Plescia J, Altieri DC. Dual regulation of ligand binding by CD11b I domain. Inhibition of intercellular adhesion and monocyte procoagulant activity by a factor X-derived peptide. J Biol Chem 1998; 273:744-8. [PMID: 9422726 DOI: 10.1074/jbc.273.2.744] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The role of coagulation factor X as a ligand for CD11b/CD18 (Mac-1, alphaMbeta2) in leukocyte adhesion was investigated. A factor X peptide, (G)L238YQAKRFKV246(G), blocked ligand binding to CD11b/CD18 and prevented monocyte procoagulant activity. This peptide also inhibited monocytic THP-1 cell adhesion to tumor necrosis factor alpha-stimulated endothelium and blocked neutrophil migration through tumor necrosis factor alpha-activated endothelial cell monolayers. In contrast, other factor X-derived peptides were ineffective. Radiolabeled peptide (G)LYQAKRFKV(G) bound specifically and saturably to isolated recombinant CD11b I domain. Functionally, the factor X sequence (G)LYQAKRFKV(G) dose-dependently inhibited THP-1 cell attachment to intercellular adhesion molecule 1 (ICAM-1) transfectants (IC50 = approximately 50 microg/ml), indistinguishably from anti-CD18 monoclonal antibodies 60.3 and IB4. In contrast, peptide (G)LYQAKRFKV(G) failed to reduce binding of 125I-fibrinogen to immobilized CD11b I domain, which was abolished by the fibrinogen-derived peptide KYG190WTVFQKRLDGSV202. By Lineweaver-Burke analysis, peptide (G)LYQAKRFKV(G) inhibited factor X binding to CD11b/CD18 in a noncompetitive fashion, and intact factor X did not reduce monocyte-endothelial cell interaction. These data suggest that the factor X sequence (G)LYQAKRFKV(G) defines an ICAM-1-binding site on CD11b I domain physically distinct from and nonoverlapping with the fibrinogen interacting region(s). Engagement of this site induces a conformational change in the holoreceptor, which disrupts a distant factor X-binding site required for monocyte procoagulant activity. These observations demonstrate a dual regulatory role of CD11b I domain in ligand binding and provide a molecular basis for the recently reported anti-inflammatory properties of factor X homologous sequences in vivo.
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Affiliation(s)
- M Mesri
- Department of Pathology, Boyer Center for Molecular Medicine, Yale University School of Medicine, New Haven, Connecticut 06536, USA
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19
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Neumann FJ, Marx N, Gawaz M, Brand K, Ott I, Rokitta C, Sticherling C, Meinl C, May A, Schömig A. Induction of cytokine expression in leukocytes by binding of thrombin-stimulated platelets. Circulation 1997; 95:2387-94. [PMID: 9170401 DOI: 10.1161/01.cir.95.10.2387] [Citation(s) in RCA: 230] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Activated platelets tether and activate myeloid leukocytes. To investigate the potential relevance of this mechanism in acute myocardial infarction (AMI), we examined cytokine induction by leukocyte-platelet adhesion and the occurrence of leukocyte-platelet conjugates in patients with AMI. METHODS AND RESULTS We obtained peripheral venous blood samples in 20 patients with AMI before and daily for 5 days after direct percutaneous transluminal coronary angioplasty (PTCA) and in 20 patients undergoing elective PTCA. Throughout the study period, CD41 immunofluorescence of leukocytes (flow cytometry) revealed increased leukocyte-platelet adhesion in patients with AMI compared with control patients (mean +/- SE of fluorescence [channels] before PTCA: 77 +/- 16 versus 35 +/- 9; P = .003). In vitro, thrombin-stimulated fixed platelets bound to neutrophils and monocytes. Within 2 hours, this resulted in increased mRNA for interleukin (IL),1 beta, IL-8, and monocyte chemoattractant protein (MCP)-1 in unfractionated leukocytes. After 4 hours, IL-1 beta and IL-8 concentration of the cell-free supernatant had increased by 268 +/- 36% and 210 +/- 7%, respectively, and cellular MCP-1 content had increased by 170 +/- 8%. Addition of activated platelets to adherent monocytes had a similar effect and was associated with nuclear factor-kappa B activation. Inhibition of binding by anti-P selectin antibodies reduced the effect of activated platelets on cytokine production. CONCLUSIONS In patients with AMI, leukocyte-platelet adhesion is increased. Binding of activated platelets induces IL-1 beta, IL-8, and MCP-1 in leukocytes. Our findings suggest that leukocyte-platelet adhesion contributes to the regulation of inflammatory responses in AMI.
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Affiliation(s)
- F J Neumann
- Medizinische Klinik, Technischen Universität München, Germany.
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20
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Giuntoli DL, Retzinger GS. Evidence for prothrombin production and thrombin expression by phorbol ester-treated THP-1 cells. Exp Mol Pathol 1997; 64:53-62. [PMID: 9203509 DOI: 10.1006/exmp.1997.2209] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
With the addition of fibrinogen, fibrin clots form in serum-free culture medium recovered from phorbol ester-treated THP-1 cells. We attribute this coagulant activity to thrombin generated as a consequence of cell stimulation because the coagulant activity exists in serum-free culture medium from treated cells only, and it is inhibited by hirudin. The thrombin does not derive from a prothrombin/thrombin contaminant since no detectable prothrombin/thrombin preexists in either the serum-free culture medium or the fibrinogen preparations used for our experiments. We hypothesized that the thrombin is synthesized by the cells themselves. In support of this hypothesis, we found that prothrombin mRNA is expressed in THP-1 cells following their treatment with phorbol ester. Accompanying expression of this mRNA, prothrombin antigen becomes detectable in lysates of PMA-treated THP-1 cells, and thrombin antigen and activity become detectable in both lysates and culture medium of treated cells. These results are consistent with the notion that certain cells of myelomonocytic lineage are capable of synthesizing proteins relevant to coagulation.
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Affiliation(s)
- D L Giuntoli
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Ohio 45267-0529, USA
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21
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Plescia J, Altieri DC. Activation of Mac-1 (CD11b/CD18)-bound factor X by released cathepsin G defines an alternative pathway of leucocyte initiation of coagulation. Biochem J 1996; 319 ( Pt 3):873-9. [PMID: 8920993 PMCID: PMC1217869 DOI: 10.1042/bj3190873] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Leucocyte initiation of coagulation preserves the haemostatic balance and may aberrantly contribute to vascular injury. In addition to the extrinsic activation mediated by tissue factor: factor VIIa, monocytes express an alternative procoagulant response after binding of the zymogen factor X to the integrin Mac-1 (CD11b/CD18). Here, factor X-activating activity was found in purified monocyte granules, and coincided with size-chromatographed fractions containing cathepsin G. In contrast, elastase-containing granule fractions did not activate factor X. In the presence of Ca2+ ions, purified cathepsin G, but not elastase, cleaved factor X to a approximately 54 kDa catalytically active derivative, structurally indistinguishable from the procoagulant product generated on monocytes after binding to Mac-1. Factor X activation by purified cathepsin G involved limited proteolysis of a novel Leu177-Leu178 peptide bond in the zymogen's activation peptide. Cathepsin G activation of factor X was completely inhibited by alpha 1 antichymotrypsin, or soybean trypsin inhibitor, or by a neutralizing antiserum to cathepsin G, while eglin, or an anti-elastase antibody, were ineffective. Affinity chromatography on active-site-dependent inhibitors Glu-Gly-Arg-chloromethyl ketone or benzamidine completely abolished factor Xa activity generated by cathepsin G. Cathepsin G was not constitutively detected on the monocyte surface by flow cytometry. However, inflammatory stimuli, including formyl peptide or phorbol ester, or Mac-1 engagement with its ligands fibrinogen, factor X or serum-opsonized zymosan, triggered monocyte degranulation and cathepsin G activation of factor X. These findings demonstrate that monocytes can alternatively initiate coagulation in a sequential three-step cascade, including (i) binding of factor X to Mac-1, (ii) discharge of azurophil granules, and (iii) limited proteolytic activation of membranebound factor X by cathepsin G. By rapidly forming thrombin and factor Xa in a protected membrane microenvironment, this pathway may contribute a "priming' signal for clotting, anticoagulation and vascular cell signal transduction, in vivo.
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Affiliation(s)
- J Plescia
- Boyer Center for Molecular Medicine, Department of Pathology, Yale University School of Medicine, New Haven, CT 06536, USA
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22
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Herzberg MC. Platelet-streptococcal interactions in endocarditis. CRITICAL REVIEWS IN ORAL BIOLOGY AND MEDICINE : AN OFFICIAL PUBLICATION OF THE AMERICAN ASSOCIATION OF ORAL BIOLOGISTS 1996; 7:222-36. [PMID: 8909879 DOI: 10.1177/10454411960070030201] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Infective endocarditis is characterized by the formation of septic masses of platelets on the surfaces of heart valves and is most commonly caused by viridans streptococci. Streptococcal virulence in endocarditis involves factors that promote infectivity and pathogenicity. Adhesins and exopolysaccharide (glycocalyx) contribute to infectivity. Although many factors may contribute to pathogenicity, the platelet aggregation-associated protein (PAAP) of Streptococcus sanguis contributes directly to the development of experimental endocarditis. PAAP is synthesized as a rhamnose-rich glycoprotein of 115 kDa and contains a collagen-like platelet-interactive domain, pro-gly-glu-gln-gly-pro-lys. Expressed on the cell wall of platelet aggregation-inducing strains (Agg+) of S. sanguis, PAAP apparently interacts with a signal-transducing receptor complex on platelets, which includes a novel 175-kDa alpha 2-integrin-associated protein and a 65-kDa collagen-binding component. From available data, the role of PAAP in the pathogenesis of experimental endocarditis may be explained by a proposed mechanistic model. On injured heart valves, PAAP first enhances platelet accumulation into a fibrin-enmeshed thrombus (vegetation), within which S. sanguis colonizes. Colonizing bacteria must resist platelet microbicidal protein (PMPR). The aggregation of platelets on the heart valve may be potentiated by an ectoATPase expressed on the surface of the S. sanguis and platelet alpha-adrenoreceptors that respond to endogenous catecholamines. The expression of PAAP may be modified during infection. Collagen is exposed on damaged heart valves; fever (heat shock) occurs during endocarditis. In response to heat shock or collagen in vitro, PAAP expression is altered. After colonization, streptococcal exotoxin(s) may cause fever. Proteases and other enzymes from streptococci and host sources may directly destroy the heart valves. When PAAP is unexpressed or neutralized with specific antibodies, experimental endocarditis runs a milder course and vegetations are smaller. The data suggest strongly, therefore, that the role of PAAP may overlap the colonization function of putative adhesins such as FimA or SsaB. Finally, PAAP also contributes to the development of the characteristic septic mural thrombus (vegetation) of infective endocarditis and the signs of valvular pathology.
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Affiliation(s)
- M C Herzberg
- Department of Preventive Sciences, School of Dentistry, University of Minnesota, Minneopolis 55455, USA
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Geuijen CA, Willems RJ, Mooi FR. The major fimbrial subunit of Bordetella pertussis binds to sulfated sugars. Infect Immun 1996; 64:2657-65. [PMID: 8698492 PMCID: PMC174123 DOI: 10.1128/iai.64.7.2657-2665.1996] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Bordetella pertussis fimbriae are composed of major and minor subunits, and recently it was shown that the minor fimbrial subunit binds to Vla-5, a receptor located on monocytes (W. Hazenbos, C. Geuijen, B. van den Berg, F. Mooi, and R. van Furth, J. Infect. Dis. 171:924-929, 1995). Here we present evidence that the major subunits bind to sulfated sugars, which are ubiquitous in the respiratory tract. Binding was observed to chondroitin sulfate, heparan sulfate, and dextran sulfate but not to dextran. Removal of the minor subunit from fimbriae did not significantly affect binding to sulfated sugars, indicating that the major subunit alone is sufficient for this binding. Fimbriae were also able to bind HEp-2 cells, which are known to display glycoconjugates on their surface. This binding was not dependent on the presence of the minor subunit. However, binding was dependent on the sulfation state of the glycoconjugates, since inhibition of the sulfation resulted in a significant reduction of fimbria binding. The specificity of fimbria binding was further characterized by using heparan sulfate-derived disaccharides in inhibition assays. Two disaccharides were highly effective inhibitors, and it was observed that both the degree of sulfation and the arrangement of the sulfate groups on the disaccharides were important for binding to fimbriae. B. pertussis bacteria also bound to sulfated sugars and HEp-2 cells, and analysis of B. pertussis mutants indicated that both filamentous hemagglutinin and fimbriae were required for this binding. A host protein present in the extracellular matrix, fibronectin, has binding activities similar to those of B. pertussis fimbriae, binding to both Vla-5 and sulfated sugars. Two regions in the major fimbrial subunit were identified which showed similarity with fibronectin peptides which bind to sulfated sugars. Thus, B. pertussis fimbriae exemplify molecular mimicry and may co-opt host processes by mimicking natural ligand-receptor interactions.
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Affiliation(s)
- C A Geuijen
- Molecular Microbiology Unit, National Institute of Health and Environmental Protection, The Netherlands
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Abstract
The identification of the blood-clotting inhibitor, protein S, as a ligand for a previously 'orphan' family of receptor tyrosine kinases demonstrates a new role for clotting and anti-clotting proteins in regulating cell proliferation.
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Affiliation(s)
- C T Esmon
- Oklahoma Medical Research Foundation, Department of Pathology and Biochemistry, University of Oklahoma Health Sciences Center, Oklahoma City, USA
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