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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] [What about the content of this article? (0)] [Affiliation(s)] [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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2
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Coenjaerts FE, Walenkamp AM, Mwinzi PN, Scharringa J, Dekker HA, van Strijp JA, Cherniak R, Hoepelman AI. Potent inhibition of neutrophil migration by cryptococcal mannoprotein-4-induced desensitization. J Immunol 2001; 167:3988-95. [PMID: 11564818 DOI: 10.4049/jimmunol.167.7.3988] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cryptococcal capsular Ags induce the production of proinflammatory cytokines in patients with cryptococcal meningitis. Despite this, their cerebrospinal fluid typically contains few neutrophils. Capsular glucuronoxylomannan is generally considered to mediate the inhibition of neutrophil extravasation. In the current study, culture supernatant harvested from the nonglucuronoxylomannan-producing strain CAP67 was found to be as potent as supernatant from wild-type strains in preventing migration. We identified capsular mannoprotein (MP)-4 as the causative agent. Purified MP-4 inhibited migration of neutrophils toward platelet-activating factor, IL-8, and fMLP, probably via a mechanism involving chemoattractant receptor cross-desensitization, as suggested by its direct chemotactic activity. Supporting this hypothesis, MP-4 elicited Ca(2+) transients that were inhibited by preincubation with either fMLP, IL-8, or C5a, but not platelet-activating factor, and vice versa. Moreover, MP-4 strongly decreased the neutrophil surface expression of L-selectin and induced shedding of TNF receptors p55/p75, whereas CD11b/18 increased. Finally, MP-4 was clearly detectable in both serum and cerebrospinal fluid of patients suffering from cryptococcal meningitis. These findings identify MP-4 as a novel capsular Ag prematurely activating neutrophils and desensitizing them toward a chemoattractant challenge.
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Affiliation(s)
- F E Coenjaerts
- Division Infectious Diseases and AIDS, Department of Medicine, University Medical Center, 3508 GA Utrecht, The Netherlands.
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Lipovsky MM, Tsenova L, Coenjaerts FE, Kaplan G, Cherniak R, Hoepelman AI. Cryptococcal glucuronoxylomannan delays translocation of leukocytes across the blood-brain barrier in an animal model of acute bacterial meningitis. J Neuroimmunol 2000; 111:10-4. [PMID: 11063816 DOI: 10.1016/s0165-5728(00)00354-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In bacterial meningitis, neurological damage is associated with a high influx of polymorphonuclear leukocytes (PMN) into the brain. Previous data suggest that the capsular component of the fungus C. neoformans, glucuronoxylomannan (GXM), interferes with PMN-migration into the cerebrospinal fluid (CSF). Therefore, a rabbit model of bacterial meningitis was treated intravenously with GXM. This resulted in (1) a reduction of PMN in the CSF at 6 h (P=0.05), (2) reduced peak TNF-alpha concentrations in the CSF, and (3) diminished tissue inflammation and intravascular margination of PMN in GXM-treated animals. Thus, GXM may represent a novel adjuvant anti-inflammatory agent in bacterial meningitis.
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Affiliation(s)
- M M Lipovsky
- Department of Medicine, Division of Infectious Diseases and AIDS, Eijkman Winkler Institute, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands
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Walenkamp AM, Scharringa J, Schramel FM, Coenjaerts FE, Hoepelman IM. Quantitative analysis of phagocytosis of Cryptococcus neoformans by adherent phagocytic cells by fluorescence multi-well plate reader. J Microbiol Methods 2000; 40:39-45. [PMID: 10739341 DOI: 10.1016/s0167-7012(99)00128-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Macrophages and monocytes are adherent phagocytic cells which play an important role in host defence against the yeast-like fungus Cryptococcus neoformans. Before, phagocytosis by adherent phagocytes could only be measured by means of microscopy or by a radioactive assay, which both have obvious disadvantages. We have developed a new, rapid and objective method to measure phagocytosis of C. neoformans by adherent phagocytes (e.g. alveolar macrophages) using a fluorescence multi-well plate reader. This method allows us to discriminate accurately between adherence and internalisation of C. neoformans by macrophages during long term incubation. In addition, the method was used to study the role of the mannose receptor in phagocytosis of the acapsular yeast in the absence of serum by human monocyte-derived macrophages (MDM).
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Affiliation(s)
- A M Walenkamp
- The Eijkman-Winkler Institute for Microbiology, Infectious Diseases and Inflammation, Division of Vaccines, University Hospital Utrecht, The Netherlands
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Walenkamp AM, Chaka WS, Verheul AF, Vaishnav VV, Cherniak R, Coenjaerts FE, Hoepelman IM. Cryptococcus neoformans and its cell wall components induce similar cytokine profiles in human peripheral blood mononuclear cells despite differences in structure. FEMS Immunol Med Microbiol 1999; 26:309-18. [PMID: 10575143 DOI: 10.1111/j.1574-695x.1999.tb01403.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We studied the cytokine profile of peripheral blood mononuclear cells after stimulation with various cryptococcal strains or its purified cell wall components. After 3 h of stimulation, tumor necrosis factor (TNF) alpha levels were strongly increased, whereas interferon (IFN) gamma and interleukin (IL) 10 levels were increased only slightly, or not at all (respectively). In contrast, after 18 h, TNF-alpha and IFN-gamma levels were (strongly) decreased, whereas the IL-10 levels were increased. The IL-1beta, IL-6 and IL-8 levels were equally high throughout the experiment. In order to establish which of the cryptococcal envelope components contributed most to the observed cytokine profile induced by whole cryptococci, glucuronoxylomannan, galactoxylomannan and mannoproteins were purified and partially characterized biochemically. All cryptococcal components elicited a similar cytokine pattern despite the differences in structure.
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Affiliation(s)
- A M Walenkamp
- Eijkman-Winkler Institute for Microbiology, Infectious Diseases and Inflammation, University Hospital, room G04.614, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
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Verheule S, van Batenburg CA, Coenjaerts FE, Kirchhoff S, Willecke K, Jongsma HJ. Cardiac conduction abnormalities in mice lacking the gap junction protein connexin40. J Cardiovasc Electrophysiol 1999; 10:1380-9. [PMID: 10515563 DOI: 10.1111/j.1540-8167.1999.tb00194.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The gap junction protein connexin40 (Cx40) normally is expressed in the murine atrial myocardium and ventricular conduction system. In mice lacking Cx40, several changes in the surface ECG have been described. In this study, we analyzed cardiac conduction in more detail. METHODS AND RESULTS In open chest mice under urethane anesthesia, epicardial electrodes were used to determine a number of atrial and ventricular pacing parameters. The corrected sinus node recovery time was significantly longer in Cx40-/- mice than in Cx40+/+ mice (44.4 +/- 7.2 msec vs 35.5 +/- 8.0 msec). In addition, the Wenckebach period was longer in Cx40-/- mice compared with the wild type (84.6 +/- 5.4 msec vs 78.8 +/- 3.6 msec), with the AV node probably limiting AV conduction in both cases. Whereas arrhythmias could not be induced by ventricular burst pacing in any of the mice, atrial burst pacing induced atrial tachyarrhythmias in 5 of 10 Cx40-/- mice, but not in any of 9 Cx40+/+ mice. Conduction velocities were measured in vivo using an array of unipolar recording electrodes. Ventricular conduction velocity did not differ between the groups, but atrial conduction velocity was reduced by 30% in Cx40-/- mice compared with the wild type. Heterozygous Cx40+/- mice did not differ significantly from the wild type in any respect. CONCLUSION These findings indicate that in the atria and the AV conduction system, Cx40 is an important determinant of conduction.
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Affiliation(s)
- S Verheule
- Department of Medical Physiology and Sports Medicine, Utrecht University, The Netherlands.
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MESH Headings
- Adenoviruses, Human/genetics
- Adenoviruses, Human/metabolism
- Base Sequence
- Centrifugation, Zonal/methods
- Chromatography, Ion Exchange/methods
- DNA Replication
- DNA, Viral/biosynthesis
- DNA, Viral/chemistry
- DNA, Viral/isolation & purification
- DNA-Binding Proteins/analysis
- DNA-Binding Proteins/isolation & purification
- DNA-Binding Proteins/metabolism
- DNA-Directed DNA Polymerase/isolation & purification
- DNA-Directed DNA Polymerase/metabolism
- HeLa Cells
- Humans
- Kinetics
- Models, Structural
- Molecular Sequence Data
- Phosphoproteins/isolation & purification
- Phosphoproteins/metabolism
- Plasmids
- Protein Precursors/isolation & purification
- Protein Precursors/metabolism
- Repetitive Sequences, Nucleic Acid
- Replication Origin
- Templates, Genetic
- Transcription Factors/isolation & purification
- Transcription Factors/metabolism
- Viral Proteins/analysis
- Viral Proteins/isolation & purification
- Viral Proteins/metabolism
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Affiliation(s)
- F E Coenjaerts
- Laboratory for Physiological Chemistry, Utrecht University, The Netherlands
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Coenjaerts FE, van der Vliet PC. Early dissociation of nuclear factor I from the origin during initiation of adenovirus DNA replication studied by origin immobilization. Nucleic Acids Res 1994; 22:5235-40. [PMID: 7816611 PMCID: PMC332066 DOI: 10.1093/nar/22.24.5235] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The DNA-binding domain of Nuclear Factor I (NFIBD) enhances initiation of adenovirus DNA replication up to 50-fold by binding to the auxiliary region of the origin and positioning the viral DNA polymerase. To study if and when NFIBD dissociates from the template, we immobilized origin DNA to glutathione-agarose beads by means of a GST-NFIBD fusion protein. This immobilized template is active in replication. By analyzing the release of prelabeled templates from the beads under different conditions, we show that NFIBD dissociates already early during initiation. During preinitiation NFIBD remains bound, but as soon as dCTP, dATP or dTTP are added, efficient dissociation occurs. A much lower dissociation level was induced by addition of dGTP. Since dCTP, dATP and dTTP are required for formation of a pTP-CAT initiation intermediate, we explain our results by conformational changes occurring in the polymerase during initiation leading to disruption of both the interaction between the polymerase and NFI as well as the interaction between NFI and the DNA.
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Affiliation(s)
- F E Coenjaerts
- Laboratory for Physiological Chemistry, Utrecht University, The Netherlands
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Coenjaerts FE, van Oosterhout JA, van der Vliet PC. The Oct-1 POU domain stimulates adenovirus DNA replication by a direct interaction between the viral precursor terminal protein-DNA polymerase complex and the POU homeodomain. EMBO J 1994; 13:5401-9. [PMID: 7957106 PMCID: PMC395497 DOI: 10.1002/j.1460-2075.1994.tb06875.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The bipartite POU domain of transcription factor Oct-1 stimulates adenovirus DNA replication through an interaction with the octamer sequence present in the auxiliary origin. Employing an immobilized in vitro DNA replication system, we show that the POU domain enhances the formation of a pre-initiation complex composed of the viral precursor terminal protein-DNA polymerase (pTP-pol) complex and the origin. To investigate the mechanism of stimulation we have explored protein-protein interactions between the POU domain and the pTP-pol complex. Such an interaction could be detected using a GST-POU fusion protein bound to glutathione-agarose beads. Binding was also observed with the POU homeodomain (POUHD), albeit weaker than with the intact POU domain, but not with the POU specific subdomain. Four point mutations localized in the POUHD were analyzed for pTP-pol binding. Two of these, E22A and E30A, bound pTP-pol equally as well as the wild-type, while the other two, Q24A and E29A, were able to bind 2- to 4-fold better. These mutations are localized in the same region where the HSV transactivator VP16 binds, but did not coincide with the VP16 contacts. A direct correlation between pTP-pol binding and stimulation of DNA replication in vitro was observed for all mutants, suggesting that stimulation by the POU domain is caused by an interaction with the viral pTP-pol complex.
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Affiliation(s)
- F E Coenjaerts
- Laboratory for Physiological Chemistry, University of Utrecht, The Netherlands
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10
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Tucker PA, Tsernoglou D, Tucker AD, Coenjaerts FE, Leenders H, van der Vliet PC. Crystal structure of the adenovirus DNA binding protein reveals a hook-on model for cooperative DNA binding. EMBO J 1994; 13:2994-3002. [PMID: 8039495 PMCID: PMC395187 DOI: 10.1002/j.1460-2075.1994.tb06598.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The adenovirus single-stranded DNA binding protein (Ad DBP) is a multifunctional protein required, amongst other things, for DNA replication and transcription control. It binds to single- and double-stranded DNA, as well as to RNA, in a sequence-independent manner. Like other single-stranded DNA binding proteins, it binds ssDNA, cooperatively. We report the crystal structure, at 2.6 A resolution, of the nucleic acid binding domain. This domain is active in DNA replication. The protein contains two zinc atoms in different, novel coordinations. The zinc atoms appear to be required for the stability of the protein fold rather than being involved in direct contacts with the DNA. The crystal structure shows that the protein contains a 17 amino acid C-terminal extension which hooks onto a second molecule, thereby forming a protein chain. Deletion of this C-terminal arm reduces cooperativity in DNA binding, suggesting a hook-on model for cooperativity. Based on this structural work and mutant studies, we propose that DBP forms a protein core around which the single-stranded DNA winds.
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Affiliation(s)
- P A Tucker
- European Molecular Biology Laboratory, Heidelberg, Germany
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Coenjaerts FE, De Vries E, Pruijn GJ, Van Driel W, Bloemers SM, Van der Lugt NM, Van der Vliet PC. Enhancement of DNA replication by transcription factors NFI and NFIII/Oct-1 depends critically on the positions of their binding sites in the adenovirus origin of replication. Biochim Biophys Acta 1991; 1090:61-9. [PMID: 1883843 DOI: 10.1016/0167-4781(91)90037-m] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The origin of DNA replication of many human adenoviruses is composed of a highly conserved core origin and an auxiliary region, containing the binding sites for NFI and NFIII/Oct-1. We examined enhancement of DNA replication in vitro by the purified functional DNA-binding domains of NFI (NFI-BD) and NFIII/Oct-1 (the POU domain), using origins in which the positions of the binding sites for these proteins were transposed. Insertion or deletion of two or three base pairs between the core origin and the NFI binding site resulted in a 3-5-fold decrease of stimulation, whereas larger insertions gradually reduced the stimulation further. Mutants in which the NFI binding site was separated approximately one or two helical turns from the core origin by AT-rich sequences could still be stimulated by NFI. In contrast, insertion of two or more base pairs between the NFI and NFIII/Oct-1 binding sites abolished stimulation by NFIII/Oct-1 almost completely. Furthermore, stimulation by this protein was lost when the Ad2 NFIII/Oct-1 binding site was transposed to a position closer to the core origin, destroying the NFI binding site. This shows that the position of the NFIII/Oct-1 binding site is essential for stimulation. Models to explain these position-dependent effects on stimulation are discussed.
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Affiliation(s)
- F E Coenjaerts
- Laboratory for Physiological Chemistry, University of Utrecht, The Netherlands
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Abstract
We have isolated a cDNA encoding the 84-kD subunit of NFIV. Tryptic peptide sequences were identified within the coding sequences, confirming its proper identity. The primary sequence of the protein is identical to that of the large subunit of the Ku autoantigen. A missing NFIV peptide sequence was identified within the sequence of the small subunit of Ku. In addition, the proteins are identical in immunological aspects. We suggest that the Ku and NFIV proteins are identical. This connection adds new biochemical data to our knowledge of the Ku autoantigen.
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Affiliation(s)
- M H Stuiver
- Laboratory for Physiological Chemistry, University of Utrecht, The Netherlands
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