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Ma J, Wang B, Yu L, Song B, Yu Y, Wu S, Dong Y, Zhu Z, Cui Y. The novel combinations of CTB, CpG, and aluminum hydroxide significantly enhanced the immunogenicity of clumping factor A 221-550 of Staphylococcus aureus. Biosci Biotechnol Biochem 2020; 84:1846-1855. [PMID: 32501144 DOI: 10.1080/09168451.2020.1771170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Here, we prepared the novel combined adjuvants, CTB as intra-molecular adjuvant, CpG and aluminum hydroxide (Alum) to strengthen the immunogenicity of clumping factor A221-550 of Staphylococcus aureus (S. aureus). The protein-immunoactive results showed CTB-ClfA221-550 elicited the strong immune responses to serum from mice immunized with CTB and ClfA221-550, respectively. The mice immunized with CTB-ClfA221-550 plus CpG and Alum adjuvant exhibited significantly stronger CD4+ T cell responses for IFN-γ, IL-2, IL-4, and IL-17 and displayed the higher proliferation response of splenic lymphocytes than the control groups, in addition, these mice generated the strongest humoral immune response against ClfA221-550 among all groups. Our results also showed CTB-ClfA221-550 plus CpG and Alum adjuvant obviously increased the survival percentage of the mice challenged by S. aureus. These data suggested that the novel combined adjuvants, CTB, CpG, and Alum, significantly enhance the immune responses triggered with ClfA221-550, and could provide a new approach against infection of S. aureus. ABBREVIATIONS CTB: Cholera Toxin B; CpG: Cytosine preceding Guanosine; ODN: Oligodeoxynucleotides; Alum: Aluminum hydroxide; TRAP: Target of RNAIII-activating Protein; TLR9: Toll-like Receptor 9; TMB: 3, 3', 5, 5'-tetramethylbenzidine; mAbs: Monoclonal Antibodies; OD: Optical Densities; S. aureus: Staphylococcus aureus; ClfA: Clumping factor A; FnBPA: Fibronection-binding protein A; IsdB: Iron-regulated surface determinant B; SasA: Staphylococcus aureus Surface Protein A; GapC: Glycer-aldehyde-3-phosphate dehydrogenase-C.
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Affiliation(s)
- Jinzhu Ma
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Beiyan Wang
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Liquan Yu
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Baifen Song
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Yongzhong Yu
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Shuangshuang Wu
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Yazun Dong
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Zhanbo Zhu
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University , Daqing, China
| | - Yudong Cui
- College of Life Science and Technology, Heilongjiang Bayi Agricultural University , Daqing, China
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Abstract
The main strategies used by pathogenic bacteria to infect eukaryotic tissue include their adherence to cells and the extracellular matrix (ECM), the subsequent colonization and invasion as well as the evasion of immune defences. A variety of structurally and functionally characterized adhesins and binding proteins of gram-positive bacteria facilitate these processes by specifically recognizing and interacting with various components of the host ECM, including different collagens, fibronectin and other macromolecules. The ECM affects the cellular physiology of our body and is critical for adhesion, migration, proliferation, and differentiation of many host cell types, but also provides the support for infiltrating pathogens, particularly under conditions of injury and trauma. Moreover, microbial binding to a variety of adhesive components in host tissue fluids leads to structural and/or functional alterations of host proteins and to the activation of cellular mechanisms that influence tissue and cell invasion of pathogens. Since the diverse interactions of gram-positive bacteria with the ECM represent important pathogenicity mechanisms, their characterization not only allows a better understanding of microbial invasion but also provides clues for the design of novel therapeutic strategies to manage infectious diseases.
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Harraghy N, Seiler S, Jacobs K, Hannig M, Menger MD, Herrmann M. Advances in in Vitro and in Vivo Models for Studying the Staphylococcal Factors Involved in Implant Infections. Int J Artif Organs 2018; 29:368-78. [PMID: 16705605 DOI: 10.1177/039139880602900406] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Implant infections due to staphylococci are one of the greatest threats facing patients receiving implant devices. For many years researchers have sought to understand the mechanisms involved in the adherence of the bacterium to the implanted device and the formation of the unique structure, the biofilm, which protects the indwelling bacteria from the host defence and renders them resistant to antibiotic treatment. A major goal has been to develop in vitro and in vivo models that adequately reflect the real-life situation. From the simple microtiter plate assay and scanning electron microscopy, tools for studying adherence and biofilm formation have since evolved to include specialised equipment for studying adherence, flow cell systems, real-time analysis of biofilm formation using reporter gene assays both in vitro and in vivo, and a wide variety of animal models. In this article, we discuss advances in the last few years in selected in vitro and in vivo models as well as future developments in the study of adherence and biofilm formation by the staphylococci.
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Affiliation(s)
- N Harraghy
- Institute of Medical Microbiology and Hygiene, University of Saarland, Homburg/Saar, Germany.
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Abstract
AbstractPersistent staphylococcal infections are a major medical problem, especially when they occur on implanted materials or intravascular catheters. This review describes some of the recently discovered molecular mechanisms ofStaphylococcus aureusattachment to host proteins coating biomedical implants. These interactions involve specific surface proteins, called bacterial adhesins, that recognize specific domains of host proteins deposited on indwelling devices, such as fibronectin, fibrinogen, or fibrin. Elucidation of molecular mechanisms ofS aureusadhesion to the different host proteins may lead to the development of specific inhibitors blocking attachment ofS aureus, which may decrease the risk of bacterial colonization of indwelling devices.
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Rochford E, Poulsson A, Salavarrieta Varela J, Lezuo P, Richards R, Moriarty T. Bacterial adhesion to orthopaedic implant materials and a novel oxygen plasma modified PEEK surface. Colloids Surf B Biointerfaces 2014; 113:213-22. [DOI: 10.1016/j.colsurfb.2013.09.012] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Revised: 08/23/2013] [Accepted: 09/05/2013] [Indexed: 10/26/2022]
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Kawahara D, Matsuda T. Hydrodynamic shear-stress-dependent retention of endothelial and endothelial progenitor cells adhered to vascular endothelial growth factor-fixed surfaces. J Biomed Mater Res B Appl Biomater 2012; 100:1218-28. [DOI: 10.1002/jbm.b.32686] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 11/02/2012] [Accepted: 12/22/2011] [Indexed: 01/28/2023]
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[Inhibition of Staphylococcus epidermidis adhesion on titanium surface with bioactive water-soluble copolymers bearing sulfonate, phosphate or carboxylate functions]. ACTA ACUST UNITED AC 2012; 60:84-90. [PMID: 22406062 DOI: 10.1016/j.patbio.2010.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Accepted: 07/01/2010] [Indexed: 11/21/2022]
Abstract
Implanted prostheses are sometimes subject to bacterial infections, which can threat their benefit rule on a long-term basis. Various methods are studied to fight against these infections. Among them, the grafting of bioactive polymers onto the prosthesis surface shows up as a promising way to the problem of infections. This work presents the influence of various water-soluble bioactive polymers on the inhibition of the Staphylococcus epidermidis adhesion on the titanium samples surfaces initially preadsorbed with various proteins. Whatever the studied protein is, it is shown that the bioactive polymer containing sulfonate functions generates an inhibition of the adhesion of Staphylococcus epidermidis. For a plasma preadsorption, the inhibition rate rises up to 68% when the concentration of sulfonate function is 2.5μmol/L. Titanium surfaces grafted with the bioactive polymer were also tested. We find an inhibitive activity of the adhesion close to that of the previous case. These preliminary results can point up a clinical interest in the fight against the medical devices infection, because they highlight a clear local effect of S. epidermidis adhesion inhibition. Copolymers containing other functional groups (phosphate or carboxylate) were dissolved in a bacterial suspension to monitor the influence of the composition on the adhesion inhibition. Their inhibition rates are not significantly lower than those of pNaSS homopolymers, as much as the sulfonate function proportion remains higher than 50%. Thus, the sulfonate function is the main responsible for the inhibition of the S. epidermidis adhesion.
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Sabbadini PS, Genovez MRN, Silva CFD, Adelino TLN, Santos CSD, Pereira GA, Nagao PE, Dias AADSDO, Mattos-Guaraldi AL, Hirata Júnior R. Fibrinogen binds to nontoxigenic and toxigenic Corynebacterium diphtheriae strains. Mem Inst Oswaldo Cruz 2010; 105:706-11. [DOI: 10.1590/s0074-02762010000500018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 05/18/2010] [Indexed: 11/22/2022] Open
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Cell surface hydrophobicity, biofilm formation, adhesives properties and molecular detection of adhesins genes in Staphylococcus aureus associated to dental caries. Microb Pathog 2010; 49:14-22. [DOI: 10.1016/j.micpath.2010.03.007] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 03/09/2010] [Accepted: 03/10/2010] [Indexed: 11/18/2022]
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Kalasin S, Dabkowski J, Nüsslein K, Santore MM. The role of nano-scale heterogeneous electrostatic interactions in initial bacterial adhesion from flow: A case study with Staphylococcus aureus. Colloids Surf B Biointerfaces 2010; 76:489-95. [DOI: 10.1016/j.colsurfb.2009.12.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2009] [Revised: 12/13/2009] [Accepted: 12/15/2009] [Indexed: 11/25/2022]
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Kalasin S, Santore MM. Non-specific adhesion on biomaterial surfaces driven by small amounts of protein adsorption. Colloids Surf B Biointerfaces 2009; 73:229-36. [DOI: 10.1016/j.colsurfb.2009.05.028] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 05/05/2009] [Accepted: 05/25/2009] [Indexed: 01/07/2023]
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Zmantar T, Chaieb K, Makni H, Miladi H, Abdallah FB, Mahdouani K, Bakhrouf A. Detection by PCR of adhesins genes and slime production in clinicalStaphylococcus aureus. J Basic Microbiol 2008; 48:308-14. [DOI: 10.1002/jobm.200700289] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
AIMS We have recently found that preconditioning of stainless steel surfaces with an aqueous fish muscle extract can significantly impede bacterial adhesion. The purpose of this study was to identify and characterize the primary components associated with this bacteria-repelling effect. METHODS AND RESULTS The anti-adhesive activity was assayed against Escherchia coli K-12, and bacterial adhesion was quantified by crystal violet staining and sonication methods. Proteolytic digestion, elution and fractionation experiments revealed that the anti-adhesive activity of the extract was linked to the formation of a proteinaceous conditioning film composed primarily of fish tropomyosins. These fibrous proteins formed a considerable anti-adhesive conditioning layer on and reduced bacterial adhesion to several different materials including polystyrene, vinyl plastic, stainless steel and glass. The protein adsorption profiles obtained from the various materials did not differ significantly, but elution was often incomplete making minor qualitative/quantitative differences indiscernible. CONCLUSIONS The data highlights the significance of protein conditioning films on bacterial adhesion and emphasizes the importance of substratum's physiochemical properties and exposure time with regards to protein adsorption/elution efficiency and subsequent bacterial adhesion. SIGNIFICANCE AND IMPACT OF THE STUDY Fish tropomyosin-coatings could potentially offer a nontoxic and relatively inexpensive measure of reducing bacterial colonization of inert surfaces.
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Affiliation(s)
- R M Vejborg
- Microbial Adhesion Group, BioCentrum-DTU, Technical University of Denmark, Lyngby, Denmark
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Riffell JA, Zimmer RK. Sex and flow: the consequences of fluid shear for sperm–egg interactions. J Exp Biol 2007; 210:3644-60. [PMID: 17921166 DOI: 10.1242/jeb.008516] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SUMMARYFertilization is a complex interaction among biological traits of gametes and physical properties of the fluid environment. At the scale of fertilization (0.01–1 mm), sperm encounter eggs while being transported within a laminar (or viscous) shear flow. Varying laminar-shear in a Taylor-Couette flow tank, our experiments simulated important aspects of small-scale turbulence within the natural habitats of red abalone(Haliotis rufescens), a large marine mollusk and external fertilizer. Behavioral interactions between individual cells, sperm–egg encounter rates, and fertilization success were quantified, simultaneously, using a custom-built infrared laser and computer-assisted video imaging system. Relative to still water, sperm swam faster and moved towards an egg surface,but only in comparatively slow flows. Encounter rate, swim speed and orientation, and fertilization success each peaked at the lowest shear tested(0.1 s–1), and then decayed as shear increased beyond 1.0 s–1. The decay did not result, however, from damage to either sperm or eggs. Analytical and numerical models were used to estimate the propulsive force generated by sperm swimming (Fswim) and the shear force produced by fluid motion within the vicinity of a rotating egg(Fshear). To first order, male gametes were modeled as prolate spheroids. The ratio Fswim/Fshear was useful in explaining sperm–egg interactions. At low shears where Fswim/Fshear>1, sperm swam towards eggs, encounter rates were pronounced, and fertilization success was very high; behavior overpowered fluid motion. In contrast, sperm swimming,encounter rate and fertilization success all decayed rapidly when Fswim/Fshear<1; fluid motion dominated behavior. The shears maximizing fertilization success in the lab typically characterized natural flow microenvironments of spawning red abalone. Gamete behavior thus emerges as a critical determinant of sexual reproduction in the turbulent sea.
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Affiliation(s)
- Jeffrey A. Riffell
- Department of Ecology and Evolutionary Biology, University of California,Los Angeles, CA 90095-1606, USA
| | - Richard K. Zimmer
- Department of Ecology and Evolutionary Biology, University of California,Los Angeles, CA 90095-1606, USA
- Neurosciences Program and Brain Research Institute, University of California, Los Angeles, CA 90095-1606, USA
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Anderson BN, Ding AM, Nilsson LM, Kusuma K, Tchesnokova V, Vogel V, Sokurenko EV, Thomas WE. Weak rolling adhesion enhances bacterial surface colonization. J Bacteriol 2006; 189:1794-802. [PMID: 17189376 PMCID: PMC1855705 DOI: 10.1128/jb.00899-06] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Bacterial adhesion to and subsequent colonization of surfaces are the first steps toward forming biofilms, which are a major concern for implanted medical devices and in many diseases. It has generally been assumed that strong irreversible adhesion is a necessary step for biofilm formation. However, some bacteria, such as Escherichia coli when binding to mannosylated surfaces via the adhesive protein FimH, adhere weakly in a mode that allows them to roll across the surface. Since single-point mutations or even increased shear stress can switch this FimH-mediated adhesion to a strong stationary mode, the FimH system offers a unique opportunity to investigate the role of the strength of adhesion independently from the many other factors that may affect surface colonization. Here we compare levels of surface colonization by E. coli strains that differ in the strength of adhesion as a result of flow conditions or point mutations in FimH. We show that the weak rolling mode of surface adhesion can allow a more rapid spreading during growth on a surface in the presence of fluid flow. Indeed, an attempt to inhibit the adhesion of strongly adherent bacteria by blocking mannose receptors with a soluble inhibitor actually increased the rate of surface colonization by allowing the bacteria to roll. This work suggests that (i) a physiological advantage to the weak adhesion demonstrated by commensal variants of FimH bacteria may be to allow rapid surface colonization and (ii) antiadhesive therapies intended to prevent biofilm formation can have the unintended effect of enhancing the rate of surface colonization.
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Affiliation(s)
- Brett N Anderson
- Department of Bioengineering, University of Washington, Seattle, WA 98195-5061, USA
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Liang X, Ji Y. Alpha-toxin interferes with integrin-mediated adhesion and internalization of Staphylococcus aureus by epithelial cells. Cell Microbiol 2006; 8:1656-68. [PMID: 16984420 DOI: 10.1111/j.1462-5822.2006.00740.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Staphylococcus aureus is an important human and animal pathogen. During infection, this bacterium is able to attach to and enter host cells by using its cell surface-associated factors to bind to the host's extracellular matrix (ECM) proteins. In this study, we determined that a protein exported by S. aureus, alpha-toxin, can interfere with the integrin-mediated adhesion and internalization of S. aureus by human lung epithelial cells (A549). The downregulation of alpha-toxin production significantly increased bacterial adhesion and invasion into the epithelial cells. In contrast, bacterial adhesion and invasion was inhibited by both overproduction of alpha-toxin and the addition of alpha-toxin to the culture medium. Moreover, our results showed that the quantitative effects on invasion closely parallel those of adherence. This suggests that the effect on invasion is probably secondary to, and a consequence of, the reduced adherence caused by alpha-toxin exposure. Specifically, we demonstrated that alpha-toxin interacts with the hosts' ECM protein's receptor, beta1-integrin, which indicates that beta1-integrin may be a potential receptor of alpha-toxin on epithelial cells. Taken together, our results indicate that exported alpha-toxin inhibits the adhesion and internalization of S. aureus by interfering with integrin-mediated pathogen-host cell interactions.
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Affiliation(s)
- Xudong Liang
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA
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Blickwede M, Goethe R, Wolz C, Valentin-Weigand P, Schwarz S. Molecular basis of florfenicol-induced increase in adherence of Staphylococcus aureus strain Newman. J Antimicrob Chemother 2005; 56:315-23. [PMID: 15983028 DOI: 10.1093/jac/dki233] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES The aim of this study was to determine the molecular basis of the florfenicol-dependent increased adherence of Staphylococcus aureus strain Newman to HEp-2 cells. METHODS AND RESULTS Northern slot blot analysis showed that mRNA expression of fnbA, fnbB, coa, emp and eap, coding for adhesins, was increased in the presence of 0.5 x MIC of florfenicol. Under the same conditions expression of cap5, coding for type 5 capsular polysaccharides, was distinctly decreased. Since global regulatory systems can modulate the expression of adhesins, their role in this process was investigated by including three isogenic mutants with functionally inactive global regulator systems, agr, sar or sae. Growth in the presence of 0.5 x MIC of florfenicol significantly increased the adherence to HEp-2 cells, fibronectin and fibrinogen of the Deltaagr and Deltasar mutant strains, but not that of the Deltasae mutant strain. In contrast to components of the agr or sar system, expression of saeRS was increased, suggesting a potential sae-directed decrease in the expression of cap5 and increase in the expression of genes coding for adhesins under the influence of florfenicol. Analysis of RNA stability revealed that the increased amount of transcripts of saeRS and adherence-associated genes was due to a stabilization of the respective mRNAs by florfenicol. CONCLUSIONS Our data provide evidence that an activation of the global regulator sae and a stabilization of mRNA coding for specific adhesins seem to act synergically in generating a more adherent phenotype in the presence of a high subinhibitory concentration of florfenicol.
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Affiliation(s)
- Maren Blickwede
- Institut für Tierzucht, Bundesforschungsanstalt für Landwirtschaft (FAL), Höltystrasse 10, 31535 Neustadt-Mariensee, Germany
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Weller GER, Villanueva FS, Tom EM, Wagner WR. Targeted ultrasound contrast agents: In vitro assessment of endothelial dysfunction and multi-targeting to ICAM-1 and sialyl Lewisx. Biotechnol Bioeng 2005; 92:780-8. [PMID: 16121392 DOI: 10.1002/bit.20625] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
An ultrasound-based molecular imaging technique capable of detecting endothelial cell markers of inflammation may allow early, non-invasive assessment of vascular disease. Clinical application of targeted, acoustically-active microbubbles requires optimization of microbubble-endothelial adhesion strength to maximize image signal-to-noise ratio, as well as the ability to discern the degree of inflammation along a continuum of dysfunction. Accordingly, we hypothesized that adhesion of intercellular adhesion molecule-1 (ICAM-1)-targeted microbubbles is dependent on the degree of endothelial inflammation, and that microbubbles multi-targeted to both ICAM-1 (via anti-ICAM-1 antibodies) and selectins (via sialyl Lewisx) demonstrate greater adhesion strength than microbubbles targeted to either inflammatory marker alone. In a radial flow chamber, microbubbles were perfused across endothelial cells activated with interleukin-1beta to four different levels of inflammation, as assessed by quantitative ICAM-1 expression. ICAM-1-targeted microbubble adhesion strength increased with increasing degree of inflammation, with a relationship that was both positive and linear (r > 0.99). Microbubble adhesion strength was significantly higher for the multi-targeted microbubbles than either of the single-targeted microbubbles. These data thus demonstrate that multi-targeting of contrast microbubbles may offer improved adhesion characteristics, allowing for greater sensitivity to inflammation. Furthermore, the adhesion strength of targeted microbubbles is linearly dependent on the degree of inflammation, suggesting that targeted ultrasound imaging may offer differentiation between various degrees of endothelial dysfunction, and thus detect not only the presence, but also the severity of inflammatory disease processes.
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Affiliation(s)
- Gregory E R Weller
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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Grundmeier M, Hussain M, Becker P, Heilmann C, Peters G, Sinha B. Truncation of fibronectin-binding proteins in Staphylococcus aureus strain Newman leads to deficient adherence and host cell invasion due to loss of the cell wall anchor function. Infect Immun 2004; 72:7155-63. [PMID: 15557640 PMCID: PMC529102 DOI: 10.1128/iai.72.12.7155-7163.2004] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus fibronectin-binding proteins (FnBPs) play a critical role in S. aureus pathogenesis. FnBPs mediate adhesion to fibronectin and invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, by fibronectin bridging to the host cell fibronectin receptor integrin (alpha(5))beta(1). Strain Newman is a laboratory strain frequently used for genetic, functional, and in vivo studies. However, despite pronounced production of FnBPs, strain Newman is only weakly adherent to immobilized Fn and weakly invasive. We examined whether these effects are due to a structural difference of FnBPs. Here, we show that both fnbA(Newman) and fnbB(Newman) contain a centrally located point mutation resulting in a stop codon. This leads to a truncation of both FnBPs at the end of the C domain at identical positions. Most likely, the stop codon occurred first in fnbB(Newman) and was subsequently transferred to fnbA(Newman) by replacement of the entire region encompassing the C, D, and W domains with the respective sequence of fnbB(Newman). Using heterologous expression in Staphylococcus carnosus, we found that truncated FnBPs were completely secreted into the culture medium and not anchored to the cell wall, since they lack the sortase motif (LPETG). Consequently, this led to a loss of FnBP-dependent functions, such as strong adhesion to immobilized fibronectin, binding of fibrinogen, and host cell invasion. This mutation may explain some of the earlier reported conflicting data with strain Newman. Thus, care should be taken when drawing negative conclusions about the role of FnBPs as a virulence factor in a given model.
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Affiliation(s)
- Matthias Grundmeier
- Institute of Medical Microbiology, University of Münster, Domagkstrasse 10, D-48149 Münster, Germany
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Bjerketorp J, Rosander A, Nilsson M, Jacobsson K, Frykberg L. Sorting a Staphylococcus aureus phage display library against ex vivo biomaterial. J Med Microbiol 2004; 53:945-951. [PMID: 15358815 DOI: 10.1099/jmm.0.45638-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A phage display library made from Staphylococcus aureus DNA was sorted against a central venous catheter (CVC) that had been removed from a patient 2 days after insertion. After the first panning, approximately 50% of the clones encoded proteins known to interact with mammalian proteins. After the second and third pannings, fibrinogen-binding and beta2-glycoprotein I (beta2-GPI)-binding phage particles were clearly dominating. Proteins adsorbed to different CVCs were investigated using specific antibodies. Among the proteins probed for, fibrinogen was most abundant, but, interestingly, beta2-GPI was also detected on all tested CVCs.
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Affiliation(s)
- Joakim Bjerketorp
- Department of Microbiology, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden
| | - Anna Rosander
- Department of Microbiology, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden
| | - Martin Nilsson
- Department of Microbiology, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden
| | - Karin Jacobsson
- Department of Microbiology, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden
| | - Lars Frykberg
- Department of Microbiology, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden
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Hall AE, Domanski PJ, Patel PR, Vernachio JH, Syribeys PJ, Gorovits EL, Johnson MA, Ross JM, Hutchins JT, Patti JM. Characterization of a protective monoclonal antibody recognizing Staphylococcus aureus MSCRAMM protein clumping factor A. Infect Immun 2004; 71:6864-70. [PMID: 14638774 PMCID: PMC308922 DOI: 10.1128/iai.71.12.6864-6870.2003] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Staphylococcus aureus MSCRAMM (microbial surface components recognizing adhesive matrix molecules) protein clumping factor A (ClfA) has been shown to be a critical virulence factor in several experimental models of infection. This report describes the generation, characterization, and in vivo evaluation of a murine monoclonal antibody (MAb) against ClfA. Flow cytometric analysis revealed that MAb 12-9 recognized ClfA protein expressed by all of the clinical S. aureus strains obtained from a variety of sources. In assays measuring whole-cell S. aureus binding to human fibrinogen, MAb 12-9 inhibited S. aureus binding by over 90% and displaced up to 35% of the previously adherent S. aureus bacteria. Furthermore, a single infusion of MAb 12-9 was protective against an intravenous challenge with a methicillin-resistant strain of S. aureus in a murine sepsis model (P < 0.0001). These data suggest that anti-ClfA MAb 12-9 should be further investigated as a novel immunotherapy for the treatment and prevention of life-threatening S. aureus infections.
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Ma H, Dickinson RB. Kinetic analysis of the attachment of a biological particle to a surface by macromolecular binding. J Theor Biol 2004; 226:237-50. [PMID: 14643193 DOI: 10.1016/j.jtbi.2003.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Motivated by the problem of microbial deposition, a dynamic model is developed for the attachment of a Brownian particle to a surface mediated by colloidal forces as well as macromolecular bridging. The model predicts the attachment probability of the particle to the surface based upon the free energy as a function of fluctuating bond number and separation distance from the surface. From this model, the mean first-passage time approach is used to predict the mean time required for the particle moving from the unattached state to the attached state based on the properties of the binding macromolecules. This approach provides an analytical approximation for mean transition time from the secondary energy minimum as well as the attachment rate constant for the general case where neither binding nor particle diffusion are necessarily rate-limiting.
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Affiliation(s)
- Huilian Ma
- Department of Chemical Engineering, University of Florida, P.O. Box 116005, 221 CHE Bldg., Gainesville, FL 32611, USA
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Ardehali R, Shi L, Janatova J, Mohammad SF, Burns GL. The inhibitory activity of serum to prevent bacterial adhesion is mainly due to apo-transferrin. J Biomed Mater Res A 2003; 66:21-8. [PMID: 12833427 DOI: 10.1002/jbm.a.10493] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A marked, up to 5-fold, reduction in bacterial adhesion to Tecoflex polyurethane (PU) surfaces was observed in the presence of bovine/human serum or plasma at 0.5% or higher concentrations in the medium. Further investigation of the phenomenon resulted in identification, isolation, and characterization of the serum component with the ability to significantly reduce bacterial adhesion. Upon fractionation of bovine serum by an anion exchange chromatography, protein pools were made and analyzed by immunoelectrophoresis and by polyacrylamide gel electrophoresis in the presence of SDS and were examined for their effect on the adhesion of Staphylococcus epidermidis to PU surfaces. The pool exhibiting a significant inhibitory effect was subjected to further biochemical tests, which resulted in the identification of transferrin (Tf) as its predominant protein. Bacterial adhesion studies in the presence of purified Tf revealed that holo-Tf (iron-containing form) had no influence on bacterial adhesion at any concentration. Only apo-Tf (iron-lacking form) exerted the inhibitory effect, in a dose responsive manner at concentrations of 10 microg/mL or higher. Bacteria remained viable when suspended at the low apo-Tf concentrations, sufficient to prevent bacterial adhesion.
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Affiliation(s)
- Reza Ardehali
- Department of Bioengineering, University of Utah, Salt Lake City, Utah 84112-9202, USA
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25
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Abstract
Most bacteria that colonize eukaryotes must bind directly to host cells to establish a replicative niche. In enteric bacteria, adhesion to host cells is often promoted by a lectin found on surface-localized pili. Some pili promote efficient adhesion only when they are subjected to shear stress, as found during the flow of blood over endothelium or mucous over the surface of the epithelium.
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Thomas WE, Trintchina E, Forero M, Vogel V, Sokurenko EV. Bacterial adhesion to target cells enhanced by shear force. Cell 2002; 109:913-23. [PMID: 12110187 DOI: 10.1016/s0092-8674(02)00796-1] [Citation(s) in RCA: 417] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Surface adhesion of bacteria generally occurs in the presence of shear stress, and the lifetime of receptor bonds is expected to be shortened in the presence of external force. However, by using Escherichia coli expressing the lectin-like adhesin FimH and guinea pig erythrocytes in flow chamber experiments, we show that bacterial attachment to target cells switches from loose to firm upon a 10-fold increase in shear stress applied. Steered molecular dynamics simulations of tertiary structure of the FimH receptor binding domain and subsequent site-directed mutagenesis studies indicate that shear-enhancement of the FimH-receptor interactions involves extension of the interdomain linker chain under mechanical force. The ability of FimH to function as a force sensor provides a molecular mechanism for discrimination between surface-exposed and soluble receptor molecules.
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Brouillette E, Lacasse P, Shkreta L, Bélanger J, Grondin G, Diarra MS, Fournier S, Talbot BG. DNA immunization against the clumping factor A (ClfA) of Staphylococcus aureus. Vaccine 2002; 20:2348-57. [PMID: 12009291 DOI: 10.1016/s0264-410x(02)00100-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adhesins are considered the most important virulence factors during early phases Staphylococcus aureus infection. Antibodies induced by vaccination toward an adhesin should reduce the adherence of the pathogen and augment its phagocytosis. The present report describes the immune response of mice to a DNA vaccine directed against one of these adhesins, clumping factor A (ClfA). Injection of plasmids expressing the fibrinogen-binding region A of ClfA induced a strong and specific antibody response to ClfA in mice. In addition, splenocyte proliferation was provoked by in vitro stimulation with recombinant ClfA, thus, indicating direct implication of these cells in the immune response. Pre-incubation of S. aureus with sera of vaccinated mice reduced the pathogen's ability to bind fibrinogen by up to 92%. These pre-incubated bacteria were phagocytosed by macrophages at an increased level in vitro and were less virulent in vivo in a mouse mastitis model. However, DNA-immunized mice were not protected against an intraperitoneal challenge. Overall, the results suggest that DNA immunization against adhesins represents a new and valuable approach to combat S. aureus infections.
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Affiliation(s)
- Eric Brouillette
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, Canada
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28
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Tegoulia VA, Cooper SL. Staphylococcus aureus adhesion to self-assembled monolayers: effect of surface chemistry and fibrinogen presence. Colloids Surf B Biointerfaces 2002. [DOI: 10.1016/s0927-7765(01)00240-5] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Burdick MM, Bochner BS, Collins BE, Schnaar RL, Konstantopoulos K. Glycolipids support E-selectin-specific strong cell tethering under flow. Biochem Biophys Res Commun 2001; 284:42-9. [PMID: 11374868 DOI: 10.1006/bbrc.2001.4899] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This study provides functional evidence that glycosphingolipids constitute ligands for E-selectin but not P-selectin. Chinese hamster ovary (CHO) cells expressing E-selectin (CHO-E) or P-selectin (CHO-P) were perfused over alpha2,3-sialyl Lewis X (alpha2,3-sLe(x)) presented as the hexaosylceramide glycosphingolipid adsorbed in a monolayer containing phosphatidylcholine and cholesterol. CHO-E cells tethered extensively and formed slow, stable rolling interactions with alpha2,3-sLe(x) glycosphingolipid but not with the comparable alpha2,6-sLe(x) glycosphingolipid. Tethering/rolling varied with wall shear stress, selectin density, and ligand density. In contrast, alpha2,3-sLe(x) glycosphingolipid supported only limited, fast CHO-P cell rolling. As calculated from a stochastic model of cell rolling, the step size between successive bond releases from the alpha2,3-sLe(x) glycosphingolipid was smaller for CHO-E than CHO-P cells, whereas the opposite effect was observed for the waiting time between these events. Detachment assays revealed stronger adhesive interactions of CHO-E than CHO-P cells with alpha2,3-sLe(x) glycosphingolipid. These findings indicate that glycosphingolipids expressing an appropriate oligosaccharide mediate cell tethering/rolling via E-selectin but not P-selectin.
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Affiliation(s)
- M M Burdick
- Department of Chemical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
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30
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Que YA, Haefliger JA, Francioli P, Moreillon P. Expression of Staphylococcus aureus clumping factor A in Lactococcus lactis subsp. cremoris using a new shuttle vector. Infect Immun 2000; 68:3516-22. [PMID: 10816506 PMCID: PMC97637 DOI: 10.1128/iai.68.6.3516-3522.2000] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Staphylococcus aureus harbors redundant adhesins mediating tissue colonization and infection. To evaluate their intrinsic role outside of the staphylococcal background, a system was designed to express them in Lactococcus lactis subsp. cremoris 1363. This bacterium is devoid of virulence factors and has a known genetic background. A new Escherichia coli-L. lactis shuttle and expression vector was constructed for this purpose. First, the high-copy-number lactococcal plasmid pIL253 was equipped with the oriColE1 origin, generating pOri253 that could replicate in E. coli. Second, the lactococcal promoters P23 or P59 were inserted at one end of the pOri253 multicloning site. Gene expression was assessed by a luciferase reporter system. The plasmid carrying P23 (named pOri23) expressed luciferase constitutively at a level 10,000 times greater than did the P59-containing plasmid. Transcription was absent in E. coli. The staphylococcal clumping factor A (clfA) gene was cloned into pOri23 and used as a model system. Lactococci carrying pOri23-clfA produced an unaltered and functional 130-kDa ClfA protein attached to their cell walls. This was indicated both by the presence of the protein in Western blots of solubilized cell walls and by the ability of ClfA-positive lactococci to clump in the presence of plasma. ClfA-positive lactococci had clumping titers (titer of 4,112) similar to those of S. aureus Newman in soluble fibrinogen and bound equally well to solid-phase fibrinogen. These experiments provide a new way to study individual staphylococcal pathogenic factors and might complement both classical knockout mutagenesis and modern in vivo expression technology and signature tag mutagenesis.
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Affiliation(s)
- Y A Que
- Division of Infectious Diseases, Department of Internal Medicine, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland
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31
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Falkenback D, Lundberg F, Ribbe E, Ljungh A. Exposure of plasma proteins on Dacron and ePTFE vascular graft material in a perfusion model. Eur J Vasc Endovasc Surg 2000; 19:468-75. [PMID: 10828226 DOI: 10.1053/ejvs.1999.1075] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVES to compare the exposure of plasma proteins adsorbed onto three vascular graft materials (polytetrafluoroethylene ePTFE and two modifications of polyethyleneterephthalate Dacron). METHODS surface exposure of fibronectin, vitronectin, thrombospondin, antithrombin III, IgG, high molecular-weight kininogen, fibrinogen, albumin and plasminogen was studied by incubation with radiolabelled antibodies in a perfusion model. Perfusion times with human plasma were 1, 4, 24 and 48 hours. RESULTS all proteins could be detected at 1, 4, 24 and 48 hours after the start of perfusion. Overall, the least amount of proteins adsorbed onto ePTFE. CONCLUSIONS the low adsorption of proteins onto ePTFE may be one of the reasons for the lower incidence of infections reported with this material.
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Affiliation(s)
- D Falkenback
- Department of Infectious Diseases and Medical Microbiology, Lund University, Lund, Sweden
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32
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Francois P, Schrenzel J, Stoerman-Chopard C, Favre H, Herrmann M, Foster TJ, Lew DP, Vaudaux P. Identification of plasma proteins adsorbed on hemodialysis tubing that promote Staphylococcus aureus adhesion. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 2000; 135:32-42. [PMID: 10638692 DOI: 10.1016/s0022-2143(00)70018-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Risk factors for Staphylococcus aureus infections in patients undergoing hemodialysis include underlying disease, material-induced host defects, and the presence of vascular access catheters. To determine the specific contribution of various potentially adsorbed plasma components in promoting S aureus adhesion to shunt tubing during chronic hemodialysis, we quantified their respective amounts by Western immunoblotting and densitometry and estimated their individual adhesion-promoting activities with specific adhesion-modified bacterial mutants. Fibrinogen, which was the only component consistently present in tubing protein extracts from all patients, was adsorbed in significantly higher amounts on predialyzer than on postdialyzer tubing segments. In contrast, fibronectin and von Willebrand factor were irregularly present in patients' tubing, whereas vitronectin or thrombospondin remained undetectable in all samples. The contribution of fibrinogen in promoting S aureus attachment to hemodialysis tubing was demonstrated by (1) the significantly lower adhesion of a cIfA mutant of strain Newman compared with its parent; (2) the increased attachment of strain 8325-4 after complementation with the cloned cIfA gene on the multicopy plasmid pCF4; and (3) the general tendency for strains Newman and 8325-4(pCF4) to express higher attachment on predialyzer compared with postdialyzer tubing segments in relationship with the higher content of fibrinogen on the former material. However, the specific S aureus attachment-promoting activity of both prefilter and postfilter tubing-adsorbed fibrinogen were much lower than that of the native in vitro-adsorbed protein and may reflect masking or inactivation of the in vivo-adsorbed protein by unknown mechanisms.
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Affiliation(s)
- P Francois
- Department of Medicine, University Hospital, Geneva, Switzerland
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33
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Dominiecki ME, Weiss J. Antibacterial action of extracellular mammalian group IIA phospholipase A2 against grossly clumped Staphylococcus aureus. Infect Immun 1999; 67:2299-305. [PMID: 10225887 PMCID: PMC115970 DOI: 10.1128/iai.67.5.2299-2305.1999] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fibrinogen-dependent interactions of Staphylococcus aureus are believed to contribute to bacterial virulence by promoting bacterial attachment to fibrinogen-coated surfaces and inducing the formation of bacterial clumps that are likely resistant to phagocytosis. Although S. aureus produces several fibrinogen-binding proteins, the cell wall-associated protein clumping factor (encoded by clfA) appears to be most important in bacterial interactions with immobilized or soluble purified fibrinogen. We have compared bacterial clumping in several strains of S. aureus, including isogenic ClfA+ and ClfA- Newman strains, in the presence of purified rabbit fibrinogen, human plasma, and inflammatory fluid and examined the effect of clumping on bacterial sensitivity to mammalian group IIA phospholipase A2 (PLA2). This enzyme is the major extracellular bactericidal agent in inflammatory fluid active against S. aureus. Both ClfA-dependent and ClfA-independent bacterial clumping was observed, depending on the source and fibrinogen content of the biological fluid. In each case, clumping only partially reduced the antibacterial activity of PLA2, suggesting that this extracellular enzyme can substantially penetrate dense bacterial clumps. Bacterial clumps could be dispersed by added proteases, restoring full antibacterial activity to PLA2. Thus, the extracellular mobilization of group IIA PLA2 during inflammation may provide a mechanism by which the host can control the proliferation and survival of S. aureus even after bacterial clumping.
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Affiliation(s)
- M E Dominiecki
- Department of Microbiology, New York University School of Medicine, New York, New York 10016, USA
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34
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Navarre WW, Schneewind O. Surface proteins of gram-positive bacteria and mechanisms of their targeting to the cell wall envelope. Microbiol Mol Biol Rev 1999; 63:174-229. [PMID: 10066836 PMCID: PMC98962 DOI: 10.1128/mmbr.63.1.174-229.1999] [Citation(s) in RCA: 925] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The cell wall envelope of gram-positive bacteria is a macromolecular, exoskeletal organelle that is assembled and turned over at designated sites. The cell wall also functions as a surface organelle that allows gram-positive pathogens to interact with their environment, in particular the tissues of the infected host. All of these functions require that surface proteins and enzymes be properly targeted to the cell wall envelope. Two basic mechanisms, cell wall sorting and targeting, have been identified. Cell well sorting is the covalent attachment of surface proteins to the peptidoglycan via a C-terminal sorting signal that contains a consensus LPXTG sequence. More than 100 proteins that possess cell wall-sorting signals, including the M proteins of Streptococcus pyogenes, protein A of Staphylococcus aureus, and several internalins of Listeria monocytogenes, have been identified. Cell wall targeting involves the noncovalent attachment of proteins to the cell surface via specialized binding domains. Several of these wall-binding domains appear to interact with secondary wall polymers that are associated with the peptidoglycan, for example teichoic acids and polysaccharides. Proteins that are targeted to the cell surface include muralytic enzymes such as autolysins, lysostaphin, and phage lytic enzymes. Other examples for targeted proteins are the surface S-layer proteins of bacilli and clostridia, as well as virulence factors required for the pathogenesis of L. monocytogenes (internalin B) and Streptococcus pneumoniae (PspA) infections. In this review we describe the mechanisms for both sorting and targeting of proteins to the envelope of gram-positive bacteria and review the functions of known surface proteins.
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Affiliation(s)
- W W Navarre
- Department of Microbiology & Immunology, UCLA School of Medicine, Los Angeles, California 90095, USA
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35
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Mempel M, Schmidt T, Weidinger S, Schnopp C, Foster T, Ring J, Abeck D. Role of Staphylococcus aureus surface-associated proteins in the attachment to cultured HaCaT keratinocytes in a new adhesion assay. J Invest Dermatol 1998; 111:452-6. [PMID: 9740240 DOI: 10.1046/j.1523-1747.1998.00293.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Colonization of human skin with Staphylococcus aureus is a common feature in a variety of dermatologic diseases. In order to reproducibly investigate the adherence of Staphylococcus aureus to human epidermal cells, an in vitro assay was established using the biotin/streptavidine labeling system and the HaCaT cell line. This assay was used to define the role of several Staphylococcus aureus surface proteins with regard to their function in the staphylococcal adhesion process. Our studies included the standard laboratory strain Newman as well as its genetically constructed mutants DU5873, DU5852, DU5854, and DU5886 generated by allele replacement or transposon mutagenesis, which are deficient in the elaboration of staphylococcal protein A (spa), clumping factor (clfA), coagulase (coa), and the fibronectin-binding proteins A and B (fnbA/B), respectively. In comparison with strain Newman all mutants showed remarkably reduced adherence to the HaCaT keratinocyte cell line in our assay, yielding only between 43% and 60% of the adherence capacity of strain Newman after 60 min. Bacterial adherence could be re-established by introducing the cloned wild-type genes for the surface proteins on shuttle plasmids into the chromosomally defective mutants, thus suggesting a pathogenetic role of these proteins in the attachment of Staphylococcus aureus to human keratinocytes. Bacterial adherence was additionally enhanced by alkaline pH-values that are characteristic for skin conditions with epidermal barrier dysfunction. The use of Staphylococcus aureus mutant strains, deficient in the elaboration of defined proteins, allows specific investigation of colonization and virulence factors of this dermatologic relevant microorganism.
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Affiliation(s)
- M Mempel
- Department of Dermatology and Allergy, Biederstein, Munich, Germany
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36
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Baumgartner JN, Cooper SL. Influence of thrombus components in mediating Staphylococcus aureus adhesion to polyurethane surfaces. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1998; 40:660-70. [PMID: 9599043 DOI: 10.1002/(sici)1097-4636(19980615)40:4<660::aid-jbm18>3.0.co;2-j] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The role of protein and cellular components of thrombi in mediating bacterial adhesion on artificial surfaces was investigated in this study. The attachment of Staphylococcus aureus on polyurethane surfaces was observed directly using an automated video microscopy system. Surfaces were preconditioned with components of platelet-fibrin thrombi, including fibrinogen, thrombin, plasma, and isolated platelets. Experiments were performed in a radial flow chamber, and attachment rate constants were compared on the preconditioned surfaces in an effort to understand the complex relationship that exists between bacterial infection and thrombosis on synthetic biomaterials. Preadsorption of fibrinogen to surfaces significantly increased S. aureus adhesion compared to those preadsorbed with albumin alone while the presence of fibrin dramatically increased bacterial attachment compared to plasma preadsorbed surfaces. While the presence of adherent platelets also increased bacterial attachment, fibrin appeared to play a larger role in mediating bacterial adhesion on polyurethane surfaces. Striking results were obtained on the zwitterionic phosphonated polyurethane for a number of pretreatment conditions with regard to decreased bacterial adhesion and fibrinogen deposition.
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Affiliation(s)
- J N Baumgartner
- Department of Chemical Engineering, University of Delaware, College of Engineering, Newark 19716, USA
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37
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Baumgartner JN, Yang CZ, Cooper SL. Physical property analysis and bacterial adhesion on a series of phosphonated polyurethanes. Biomaterials 1997; 18:831-7. [PMID: 9184746 DOI: 10.1016/s0142-9612(96)00197-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Glycerophosphorylcholine (GPC) was incorporated as the chain extender in a series of poly(tetramethylene oxide)-based polyurethane block copolymers. In order to determine the feasibility of use of these polyurethanes in biomedical devices, the effects of GPC incorporation on physical properties were studied. The effect of soft-segment molecular weight was also investigated. Biocompatibility of these materials was studied with regard to bacterial adhesion and protein deposition. Tensile testing showed that as GPC content increased, elongation at break decreased, while Young's modulus increased. Differential scanning calorimetry (DSC) results showed slightly decreased glass transition temperatures (Tgs) with increasing GPC content, indicating increased phase separation. Dynamic mechanical analysis (DMA) confirmed the decrease in Tg and the increase in rubbery plateau modulus with increasing GPC content. Water absorption was also increased with GPC content. Decreased bacterial adhesion was found on the GPC-containing materials compared to other functionalized polyurethanes. These experiments were carried out in a radial flow chamber utilizing automated video microscopy. Bacterial attachment was found to be lower on the GPC-containing polyurethanes both in the absence of and after pre-adsorption with plasma proteins.
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Affiliation(s)
- J N Baumgartner
- Department of Chemical Engineering, University of Delaware, Newark 19716, USA
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38
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Abstract
The use of central venous catheters to deliver parenteral nutrition therapy is often complicated by infection. The original source of these infections has been debated but it appears that organisms colonizing the skin or those contaminating the catheter hub are most often responsible. Before forming a biofilm, an organism must first successfully attach to a surface. To do this, microbes have evolved strategies that allow them to adhere to surfaces and evade forces that would favor their detachment. Once a biofilm is formed on a catheter, the organisms are relatively safe from a host immune response and antibiotics. In this review, what is known about these interactions is discussed.
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Affiliation(s)
- W J Lewis
- Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157, USA
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40
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Wolz C, McDevitt D, Foster TJ, Cheung AL. Influence of agr on fibrinogen binding in Staphylococcus aureus Newman. Infect Immun 1996; 64:3142-7. [PMID: 8757845 PMCID: PMC174199 DOI: 10.1128/iai.64.8.3142-3147.1996] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The ability of Staphylococcus aureus to bind fibrinogen is believed to be important in promoting bacterial adherence to both intravascular catheters and host tissues during infection. We investigated the influence of the global regulator agr on the fibrinogen binding capacity and its relationship to the expression of coagulase (encoded by coa) and clumping factor (encoded by clfA) in strain Newman. Strains were obtained by transducing site-specific mutations of clfA, coa, and agr into strain Newman to obtain single, double, and triple mutants of the respective genes. As expected, the clfA mutant bound less soluble 125I-labeled fibrinogen than the corresponding coa mutant in agr+ strains; however, with agr mutant strains, the upregulation in fibrinogen binding capacity correlated mostly with the increased expression and transcription of coagulase as shown by Western (immunoblot) and Northern (RNA) blot analysis. In particular, the coa agr double mutant resulted in a significant reduction in fibrinogen binding compared with that of the agr mutant. The contribution of clfA to fibrinogen binding in agr-negative strains was less than that of coa (32,740 +/- 1,189 versus 18,141 +/- 334 and 38,919 +/- 1,021 cpm for clfA agr, coa agr, and the single agr mutant, respectively). Thus, coagulase is a major binding protein for soluble fibrinogen in the agr-negative background. In in vitro microtiter and catheter adherence assays with solid-phase fibrinogen, clumping factor, but not coagulase, plays a major role in binding to immobilized fibrinogen. coa transcription was negatively modulated by agr and occurred mainly during the exponential growth phase. In contrast, clfA transcription was agr independent and was strongest during the postexponential phase. Although an agr coa clfA triple mutant bound less soluble fibrinogen than the agr coa double mutant (8,504 +/- 831 versus 18,141 +/- 334 cpm), significant residual fibrinogen binding capacity remained in the triple mutant, thus suggesting an additional fibrinogen binding component. By using direct ligand affinity blotting with 125I-fibrinogen, we could identify coagulase and an additional unidentified 52-kDa protein as a fibrinogen binding component in cell extracts. This band was absent in the extract of the coa clfA double mutant.
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Affiliation(s)
- C Wolz
- The Laboratory of Bacterial Pathogenesis and Immunology, The Rockefeller University, New York, New York 10021, USA
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41
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François P, Vaudaux P, Foster TJ, Lew DP. Host-Bacteria Interactions in Foreign Body Infections. Infect Control Hosp Epidemiol 1996. [DOI: 10.2307/30141285] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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42
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Moreillon P, Entenza JM, Francioli P, McDevitt D, Foster TJ, François P, Vaudaux P. Role of Staphylococcus aureus coagulase and clumping factor in pathogenesis of experimental endocarditis. Infect Immun 1995; 63:4738-43. [PMID: 7591130 PMCID: PMC173679 DOI: 10.1128/iai.63.12.4738-4743.1995] [Citation(s) in RCA: 292] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The pathogenic role of staphylococcal coagulase and clumping factor was investigated in the rat model of endocarditis. The coagulase-producing and clumping factor-producing parent strain Staphylococcus aureus Newman and a series of mutants defective in either coagulase, clumping factor, or both were tested for their ability (i) to attach in vitro to either rat fibrinogen or platelet-fibrin clots and (ii) to produce endocarditis in rats with catheter-induced aortic vegetations. In vitro, the clumping factor-defective mutants were up to 100 times less able than the wild type strain to attach to fibrinogen and also significantly less adherent than the parents to platelet-fibrin clots. Coagulase-defective mutants, in contrast, were not altered in their in vitro adherence phenotype. The rate of in vivo infection was inoculum dependent. Clumping factor-defective mutants produced ca. 50% less endocarditis than the parent organisms when injected at inoculum sizes infecting, respectively, 40 and 80% (ID40 and ID80, respectively) of rats with the wild-type strain. This was a trend at the ID40 but was statistically significant at the ID80 (P < 0.05). Coagulase-defective bacteria were not affected in their infectivity. Complementation of a clumping factor-defective mutant with a copy of the wild-type clumping factor gene restored both its in vitro adherence and its in vivo infectivity. These results show that clumping factor plays a specific role in the pathogenesis of S. aureus endocarditis. Nevertheless, the rate of endocarditis with clumping factor-defective mutants increased with larger inocula, indicating the contribution of additional pathogenic determinants in the infective process.
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Affiliation(s)
- P Moreillon
- Department of Internal Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
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