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Avdonin PP, Blinova MS, Generalova GA, Emirova KM, Avdonin PV. The Role of the Complement System in the Pathogenesis of Infectious Forms of Hemolytic Uremic Syndrome. Biomolecules 2023; 14:39. [PMID: 38254639 PMCID: PMC10813406 DOI: 10.3390/biom14010039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 11/24/2023] [Accepted: 12/18/2023] [Indexed: 01/24/2024] Open
Abstract
Hemolytic uremic syndrome (HUS) is an acute disease and the most common cause of childhood acute renal failure. HUS is characterized by a triad of symptoms: microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. In most of the cases, HUS occurs as a result of infection caused by Shiga toxin-producing microbes: hemorrhagic Escherichia coli and Shigella dysenteriae type 1. They account for up to 90% of all cases of HUS. The remaining 10% of cases grouped under the general term atypical HUS represent a heterogeneous group of diseases with similar clinical signs. Emerging evidence suggests that in addition to E. coli and S. dysenteriae type 1, a variety of bacterial and viral infections can cause the development of HUS. In particular, infectious diseases act as the main cause of aHUS recurrence. The pathogenesis of most cases of atypical HUS is based on congenital or acquired defects of complement system. This review presents summarized data from recent studies, suggesting that complement dysregulation is a key pathogenetic factor in various types of infection-induced HUS. Separate links in the complement system are considered, the damage of which during bacterial and viral infections can lead to complement hyperactivation following by microvascular endothelial injury and development of acute renal failure.
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Affiliation(s)
- Piotr P. Avdonin
- Koltzov Institute of Developmental Biology RAS, ul. Vavilova, 26, 119334 Moscow, Russia; (M.S.B.); (P.V.A.)
| | - Maria S. Blinova
- Koltzov Institute of Developmental Biology RAS, ul. Vavilova, 26, 119334 Moscow, Russia; (M.S.B.); (P.V.A.)
| | - Galina A. Generalova
- Saint Vladimir Moscow City Children’s Clinical Hospital, 107014 Moscow, Russia; (G.A.G.); (K.M.E.)
- Department of Pediatrics, A.I. Evdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
| | - Khadizha M. Emirova
- Saint Vladimir Moscow City Children’s Clinical Hospital, 107014 Moscow, Russia; (G.A.G.); (K.M.E.)
- Department of Pediatrics, A.I. Evdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
| | - Pavel V. Avdonin
- Koltzov Institute of Developmental Biology RAS, ul. Vavilova, 26, 119334 Moscow, Russia; (M.S.B.); (P.V.A.)
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2
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Oehmcke-Hecht S, Maletzki C, Surabhi S, Siemens N, Khaimov V, John LM, Peter SM, Hammerschmidt S, Kreikemeyer B. Procoagulant Activity of Blood and Microvesicles Is Disturbed by Pneumococcal Pneumolysin, Which Interacts with Coagulation Factors. J Innate Immun 2022; 15:136-152. [PMID: 35843205 PMCID: PMC10643893 DOI: 10.1159/000525479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 06/06/2022] [Indexed: 11/17/2023] Open
Abstract
The coagulation and contact systems are parts of the innate immune system as they prevent bleeding and dissemination of pathogens and also contribute to microbial killing by inflammatory reactions and the release of antimicrobial peptides. Here, we investigated the influence of Streptococcus pneumoniae on the coagulation and contact system. S. pneumoniae (pneumococci), but no other investigated streptococcal species, impairs coagulation of blood by autolysis and release of pneumolysin. Defective blood coagulation results from the lysis of tissue factor-producing mononuclear cells and their procoagulant microvesicles, which are the main trigger for blood coagulation during sepsis. In addition, pneumolysin binds coagulation and contact system factors, but this does not result in activation. Thus, pneumococci modulate activation of the coagulation system by releasing pneumolysin, which could potentiate lung injury during pneumonia.
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Affiliation(s)
- Sonja Oehmcke-Hecht
- Institute of Medical Microbiology, Virology and Hygiene, Rostock University Medical Center, Rostock, Germany
| | - Claudia Maletzki
- Department of Medicine, Clinic III-Hematology, Oncology, Palliative Medicine, Rostock University Medical Center, Rostock, Germany
| | - Surabhi Surabhi
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Nikolai Siemens
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Valeria Khaimov
- Institute for ImplantTechnology and Biomaterials e.V., Rostock, Germany
| | - Lisa Marie John
- Institute of Medical Microbiology, Virology and Hygiene, Rostock University Medical Center, Rostock, Germany
| | - Sina Mariella Peter
- Institute of Medical Microbiology, Virology and Hygiene, Rostock University Medical Center, Rostock, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Bernd Kreikemeyer
- Institute of Medical Microbiology, Virology and Hygiene, Rostock University Medical Center, Rostock, Germany
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3
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Jagau H, Packirisamy S, Brandon K, Herwald H. Plasma Protein Layer Concealment Protects Streptococcus pyogenes From Innate Immune Attack. Front Cell Infect Microbiol 2021; 11:633394. [PMID: 34094995 PMCID: PMC8173628 DOI: 10.3389/fcimb.2021.633394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 05/04/2021] [Indexed: 11/13/2022] Open
Abstract
Early recognition and elimination of invading pathogens by the innate immune system, is one of the most efficient host defense mechanisms preventing the induction of systemic complications from infection. To this end the host can mobilize endogenous antimicrobials capable of killing the intruder by perforating the microbial cell wall. Here, we show that Streptococcus pyogenes can shield its outer surface with a layer of plasma proteins. This mechanism protects the bacteria from an otherwise lytic attack by LL-37 and extracellular histones, allowing the bacteria to adjust their gene regulation to an otherwise hostile environment.
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Affiliation(s)
- Hilger Jagau
- Division of Infection Medicine, Department of Clinical Sciences, Lund, Lund University, Lund, Sweden
| | - Swathi Packirisamy
- Division of Infection Medicine, Department of Clinical Sciences, Lund, Lund University, Lund, Sweden
| | - Kyle Brandon
- Division of Infection Medicine, Department of Clinical Sciences, Lund, Lund University, Lund, Sweden.,UCD School of Medicine, University College Dublin, Dublin, Ireland
| | - Heiko Herwald
- Division of Infection Medicine, Department of Clinical Sciences, Lund, Lund University, Lund, Sweden
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Ploplis VA, Castellino FJ. Host Pathways of Hemostasis that Regulate Group A Streptococcus pyogenes Pathogenicity. Curr Drug Targets 2020; 21:193-201. [PMID: 31556853 PMCID: PMC7670306 DOI: 10.2174/1389450120666190926152914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/02/2019] [Accepted: 09/06/2019] [Indexed: 11/22/2022]
Abstract
A hallmark feature of severe Group A Streptococcus pyogenes (GAS) infection is dysregulated hemostasis. Hemostasis is the primary pathway for regulating blood flow through events that contribute towards clot formation and its dissolution. However, a number of studies have identified components of hemostasis in regulating survival and dissemination of GAS. Several proteins have been identified on the surface of GAS and they serve to either facilitate invasion to host distal sites or regulate inflammatory responses to the pathogen. GAS M-protein, a surface-exposed virulence factor, appears to be a major target for interactions with host hemostasis proteins. These interactions mediate biochemical events both on the surface of GAS and in the solution when M-protein is released into the surrounding environment through shedding or regulated proteolytic processes that dictate the fate of this pathogen. A thorough understanding of the mechanisms associated with these interactions could lead to novel approaches for altering the course of GAS pathogenicity.
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Affiliation(s)
- Victoria A. Ploplis
- University of Notre Dame, W.M. Keck Center for Transgene Research, 230 Raclin-Carmichael Hall, Notre Dame, IN 46556 USA
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Francis J. Castellino
- University of Notre Dame, W.M. Keck Center for Transgene Research, 230 Raclin-Carmichael Hall, Notre Dame, IN 46556 USA
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
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5
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Tati R, Nordin S, Abdillahi SM, Mörgelin M. Biological wound matrices with native dermis-like collagen efficiently modulate protease activity. J Wound Care 2018; 27:199-209. [DOI: 10.12968/jowc.2018.27.4.199] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Ramesh Tati
- Postdoctoral Researcher, Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-221 84 Lund, Sweden
| | - Sara Nordin
- Postdoctoral Researcher, Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-221 84 Lund, Sweden
| | - Suado M Abdillahi
- Postdoctoral Researcher, Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-221 84 Lund, Sweden
| | - Matthias Mörgelin
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-221 84 Lund, Sweden, Colzyx ltd, Medicon Village, Scheelevägen 2, SE-223 81 Lund, Sweden
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Abstract
The name human contact system is related to its mode of action, as "contact" with artificial negatively charged surfaces triggers its activation. Today, it is generally believed that the contact system is an inflammatory response mechanism not only against artificial material but also against misfolded proteins and foreign organisms. Upon activation, the contact system is involved in at least two distinct (patho)physiologic processes:i. the trigger of the intrinsic coagulation via factor XI and ii. the cleavage of high molecular weight kininogen with release of bradykinin and antimicrobial peptides (AMPs). Bradykinin is involved in the regulation of inflammatory processes, vascular permeability, and blood pressure. Due to the release of AMPs, the contact system is regarded as a branch of the innate immune defense against microorganisms. There is an increasing list of pathogens that interact with contact factors, in addition to bacteria also fungi and viruses bind and activate the system. In spite of that, pathogens have developed their own mechanisms to activate the contact system, resulting in manipulation of this host immune response. In this up-to-date review, we summarize present research on the interaction of pathogens with the human contact system, focusing particularly on bacterial and viral mechanisms that trigger inflammation via contact system activation.
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Affiliation(s)
- Sonja Oehmcke-Hecht
- Institute of Medical Microbiology, Virology and Hygiene, Rostock University Medical Center, Rostock, Germany
| | - Juliane Köhler
- Institute of Medical Microbiology, Virology and Hygiene, Rostock University Medical Center, Rostock, Germany
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Yang A, Xie Z, Wang B, Colman RW, Dai J, Wu Y. An essential role of high-molecular-weight kininogen in endotoxemia. J Exp Med 2017; 214:2649-2670. [PMID: 28794132 PMCID: PMC5584120 DOI: 10.1084/jem.20161900] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 05/25/2017] [Accepted: 07/07/2017] [Indexed: 01/08/2023] Open
Abstract
High-molecular-weight kininogen (HK) is a plasma protein. Yang et al. show that HK binds LPS and supports endotoxemia. Blockade of their binding attenuates circulating LPS level. Therefore, HK is essential for endotoxemia and is a new target for LPS clearance and sepsis treatment. In this study, we show that mice lacking high-molecular-weight kininogen (HK) were resistant to lipopolysaccharide (LPS)-induced mortality and had significantly reduced circulating LPS levels. Replenishment of HK-deficient mice with human HK recovered the LPS levels and rendered the mice susceptible to LPS-induced mortality. Binding of HK to LPS occurred through the O-polysaccharide/core oligosaccharide, consistent with the ability to bind LPS from K. pneumoniae, P. aeruginosa, S. minnesota, and different E. coli strains. Binding of LPS induced plasma HK cleavage to the two-chain form (HKa, containing a heavy chain [HC] and a light chain [LC]) and bradykinin. Both HKa and the LC, but not the HC, could disaggregate LPS. The light chain bound LPS with high affinity (Kd = 1.52 × 10−9 M) through a binding site in domain 5 (DHG15). A monoclonal antibody against D5 significantly reduced LPS-induced mortality and circulating LPS levels in wild-type mice. Thus, HK, as a major LPS carrier in circulation, plays an essential role in endotoxemia.
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Affiliation(s)
- Aizhen Yang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Zhanli Xie
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Bo Wang
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China
| | - Robert W Colman
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA
| | - Jihong Dai
- Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA.,Department of Pathology and Laboratory Medicine, Rutgers-New Jersey Medical School, Newark, NJ
| | - Yi Wu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, China .,Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA
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8
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Hack K, Renzi F, Hess E, Lauber F, Douxfils J, Dogné JM, Cornelis GR. Inactivation of human coagulation factor X by a protease of the pathogen Capnocytophaga canimorsus. J Thromb Haemost 2017; 15:487-499. [PMID: 28029716 DOI: 10.1111/jth.13605] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Indexed: 01/13/2023]
Abstract
Essentials Capnocytophaga canimorsus causes severe dog bite related blood stream infections. We investigated if C. canimorsus contributes to bleeding abnormalities during infection. The C. canimorsus protease CcDPP7 causes factor X dysfunction by N-terminal cleavage. CcDPP7 inhibits coagulation in vivo, which could promote immune evasion and trigger hemorrhage. SUMMARY Background Capnocytophaga canimorsus is a Gram-negative bacterium that is present in the oral flora of dogs and causes fulminant sepsis in humans who have been bitten, licked, or scratched. In patients, bleeding abnormalities, such as petechiae, purpura fulminans, or disseminated intravascular coagulation (DIC), occur frequently. Objective To investigate whether C. canimorsus could actively contribute to these bleeding abnormalities. Methods Calibrated automated thrombogram and clotting time assays were performed to assess the anticoagulant activity of C. canimorsus 5 (Cc5), a strain isolated from a fatal human infection. Clotting factor activities were measured with factor-deficient plasma. Factor X cleavage was monitored with the radiolabeled zymogen and western blotting. Mutagenesis of Cc5 genes encoding putative serine proteases was performed to identify the protease that cleaves FX. Protein purification was performed with affinity chromatography. Edman degradation allowed the detection of N-terminal cleavage of FX. Tail bleeding times were measured in mice. Results We found that Cc5 inhibited thrombin generation and increased the prothrombin time and the activated partial thromboplastin time of human plasma via FX cleavage. A mutant that was unable to synthesize a type 7 dipeptidyl peptidase (DPP7) of the S46 serine protease family failed to proteolyse FX. The purified protease (CcDPP7) cleaved FX heavy and light chains from the N-terminus, and was active in vivo after intravenous injection. Conclusions This is, to our knowledge, the first study demonstrating a detailed mechanism for FX inactivation by a bacterial protease, and it is the first functional study associating DPP7 proteases with a potentially pathogenic outcome.
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Affiliation(s)
- K Hack
- Department of Biology, University of Namur, Namur, Belgium
| | - F Renzi
- Department of Biology, University of Namur, Namur, Belgium
| | - E Hess
- Department of Biology, University of Namur, Namur, Belgium
| | - F Lauber
- Department of Biology, University of Namur, Namur, Belgium
| | - J Douxfils
- Department of Pharmacy, University of Namur, Namur, Belgium
| | - J M Dogné
- Department of Pharmacy, University of Namur, Namur, Belgium
| | - G R Cornelis
- Department of Biology, University of Namur, Namur, Belgium
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9
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Tsai JYC, Loh JMS, Clow F, Lorenz N, Proft T. The Group A Streptococcus serotype M2 pilus plays a role in host cell adhesion and immune evasion. Mol Microbiol 2016; 103:282-298. [PMID: 27741558 DOI: 10.1111/mmi.13556] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2016] [Indexed: 01/22/2023]
Abstract
Group A Streptococcus (GAS), or Streptococcus pyogenes, is a human pathogen that causes diseases ranging from skin and soft tissue infections to severe invasive diseases, such as toxic shock syndrome. Each GAS strain carries a particular pilus type encoded in the variable fibronectin-binding, collagen-binding, T antigen (FCT) genomic region. Here, we describe the functional analysis of the serotype M2 pilus encoded in the FCT-6 region. We found that, in contrast to other investigated GAS pili, the ancillary pilin 1 lacks adhesive properties. Instead, the backbone pilin is important for host cell adhesion and binds several host factors, including fibronectin and fibrinogen. Using a panel of recombinant pilus proteins, GAS gene deletion mutants and Lactococcus lactis gain-of-function mutants we show that, unlike other GAS pili, the FCT-6 pilus also contributes to immune evasion. This was demonstrated by a delay in blood clotting, increased intracellular survival of the bacteria in macrophages, higher bacterial survival rates in human whole blood and greater virulence in a Galleria mellonella infection model in the presence of fully assembled FCT-6 pili.
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Affiliation(s)
- Jia-Yun C Tsai
- Department of Molecular Medicine & Pathology, School of Medical Sciences.,Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand
| | - Jacelyn M S Loh
- Department of Molecular Medicine & Pathology, School of Medical Sciences.,Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand
| | - Fiona Clow
- Department of Molecular Medicine & Pathology, School of Medical Sciences
| | - Natalie Lorenz
- Department of Molecular Medicine & Pathology, School of Medical Sciences
| | - Thomas Proft
- Department of Molecular Medicine & Pathology, School of Medical Sciences.,Maurice Wilkins Centre, The University of Auckland, Auckland, New Zealand
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10
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Saliva-Induced Clotting Captures Streptococci: Novel Roles for Coagulation and Fibrinolysis in Host Defense and Immune Evasion. Infect Immun 2016; 84:2813-23. [PMID: 27456827 PMCID: PMC5038080 DOI: 10.1128/iai.00307-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 07/18/2016] [Indexed: 11/20/2022] Open
Abstract
Streptococcal pharyngitis is among the most common bacterial infections, but the molecular mechanisms involved remain poorly understood. Here we investigate the interactions among three major players in streptococcal pharyngitis: streptococci, plasma, and saliva. We find that saliva activates the plasma coagulation system through both the extrinsic and the intrinsic pathways, entrapping the bacteria in fibrin clots. The bacteria escape the clots by activating host plasminogen. Our results identify a potential function for the intrinsic pathway of coagulation in host defense and a corresponding role for fibrinolysis in streptococcal immune evasion.
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Thomer L, Schneewind O, Missiakas D. Pathogenesis of Staphylococcus aureus Bloodstream Infections. ANNUAL REVIEW OF PATHOLOGY 2016; 11:343-64. [PMID: 26925499 PMCID: PMC5068359 DOI: 10.1146/annurev-pathol-012615-044351] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Staphylococcus aureus, a Gram-positive bacterium colonizing nares, skin, and the gastrointestinal tract, frequently invades the skin, soft tissues, and bloodstreams of humans. Even with surgical and antibiotic therapy, bloodstream infections are associated with significant mortality. The secretion of coagulases, proteins that associate with and activate the host hemostatic factor prothrombin, and the bacterial surface display of agglutinins, proteins that bind polymerized fibrin, are key virulence strategies for the pathogenesis of S. aureus bloodstream infections, which culminate in the establishment of abscess lesions. Pathogen-controlled processes, involving a wide spectrum of secreted factors, are responsible for the recruitment and destruction of immune cells, transforming abscess lesions into purulent exudate, with which staphylococci disseminate to produce new infectious lesions or to infect new hosts. Research on S. aureus bloodstream infections is a frontier for the characterization of protective vaccine antigens and the development of immune therapeutics aiming to prevent disease or improve outcomes.
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Affiliation(s)
- Lena Thomer
- Department of Microbiology, University of Chicago, Chicago, Illinois 60637;
| | - Olaf Schneewind
- Department of Microbiology, University of Chicago, Chicago, Illinois 60637;
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Choi KM, Jeong JM, Bae JS, Cho DH, Jung SH, Hwang JY, Baeck GW, Park CI. Coagulation factor II from rock bream (Oplegnathus fasciatus): First report on the molecular biological function and expression analysis in the teleost. FISH & SHELLFISH IMMUNOLOGY 2016; 48:145-153. [PMID: 26626585 DOI: 10.1016/j.fsi.2015.11.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 11/19/2015] [Accepted: 11/22/2015] [Indexed: 06/05/2023]
Abstract
The rapid haemostasis of fish prevents bleeding or infection that could be caused by physical properties of the aquatic environment. Additionally, the innate immune system is the first line of defence against infection and is responsible for the recognition of pathogen-associated molecular patterns, which are important for the activation of acquired immune responses. Coagulation factor II (CFII) is an important factor in the coagulation system and is involved in recognition and interaction with various bacterial and extracellular proteins. In this study, we identified and characterised the gene encoding CFII in rock bream (Oplegnathus fasciatus) (RbCFII) and analysed its expression in various tissues after a pathogen challenge. The full-length RbCFII cDNA (2079 bp) contained an open reading frame of 1854 bp encoding 617 amino acids. Alignment analysis revealed that a gamma-carboxyglutamic acid-rich domain, two kringle domains, and a trypsin-like serine protease domain of the deduced protein were well conserved. RbCFII was ubiquitously expressed in all tissues examined but, predominantly detected in the liver and skin. RbCFII expression was dramatically up-regulated in the kidney, spleen and liver after infection with Edwardsiella tarda, Streptococcus iniae, or red seabream iridovirus. The recombinant protein RbCFII (rRbCFII) produced using an Escherichia coli expression system was able to bind all examined bacteria. Interestingly, rRbCFII has agglutination activities towards E. coli and E. tarda, while no agglutination was shown toward Vibrio ordalii and S. iniae. These findings indicate that rRbCFII performs an immunological function in the immune response, and might be involved in innate immunity as well as blood coagulation.
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Affiliation(s)
- Kwang-Min Choi
- Department of Marine Biology and Aquaculture, College of Marine Science, Gyeongsang National University, 38 Cheondaegukchi-Gil, Tongyeong, Gyeongnam 650-160, Republic of Korea
| | - Ji-Min Jeong
- Department of Marine Biology and Aquaculture, College of Marine Science, Gyeongsang National University, 38 Cheondaegukchi-Gil, Tongyeong, Gyeongnam 650-160, Republic of Korea
| | - Jin-Sol Bae
- Department of Marine Biology and Aquaculture, College of Marine Science, Gyeongsang National University, 38 Cheondaegukchi-Gil, Tongyeong, Gyeongnam 650-160, Republic of Korea
| | - Dong-Hee Cho
- Department of Marine Biology and Aquaculture, College of Marine Science, Gyeongsang National University, 38 Cheondaegukchi-Gil, Tongyeong, Gyeongnam 650-160, Republic of Korea
| | - Sung Hee Jung
- Pathology Division, National Fisheries Research and Development Institute, Busan 619-900, Republic of Korea
| | - Jee-Youn Hwang
- Pathology Division, National Fisheries Research and Development Institute, Busan 619-900, Republic of Korea
| | - Gun-Wook Baeck
- Department of Marine Biology and Aquaculture, College of Marine Science, Gyeongsang National University, 38 Cheondaegukchi-Gil, Tongyeong, Gyeongnam 650-160, Republic of Korea
| | - Chan-Il Park
- Department of Marine Biology and Aquaculture, College of Marine Science, Gyeongsang National University, 38 Cheondaegukchi-Gil, Tongyeong, Gyeongnam 650-160, Republic of Korea.
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Naudin C, Hurley SM, Malmström E, Plug T, Shannon O, Meijers JCM, Mörgelin M, Björck L, Herwald H. Active but inoperable thrombin is accumulated in a plasma protein layer surrounding Streptococcus pyogenes. Thromb Haemost 2015; 114:717-26. [PMID: 25994766 DOI: 10.1160/th15-02-0127] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 04/15/2015] [Indexed: 12/23/2022]
Abstract
Activation of thrombin is a critical determinant in many physiological and pathological processes including haemostasis and inflammation. Under physiological conditions many of these functions are involved in wound healing or eradication of an invading pathogen. However, when activated systemically, thrombin can contribute to severe and life-threatening conditions by causing complications such as multiple multi-organ failure and disseminated intravascular coagulation. In the present study we investigated how the activity of thrombin is modulated when it is bound to the surface of Streptococcus pyogenes. Our data show that S. pyogenes bacteria become covered with a proteinaceous layer when incubated with human plasma, and that thrombin is a constituent of this layer. Though the coagulation factor is found attached to the bacteria with a functional active site, thrombin has lost its capacity to interact with its natural substrates and inhibitors. Thus, the interaction of bacteria with human plasma renders thrombin completely inoperable at the streptococcal surface. This could represent a host defense mechanism to avoid systemic activation of coagulation which could be otherwise induced when bacteria enter the circulation and cause systemic infection.
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Affiliation(s)
- Clément Naudin
- Clément Naudin, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center (BMC), Floor B14, Tornavägen 10, 22184 Lund, Sweden, Tel.: + 46 46 2226807, Fax: + 46 46 157756, E-mail:
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14
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Thomer L, Schneewind O, Missiakas D. Multiple ligands of von Willebrand factor-binding protein (vWbp) promote Staphylococcus aureus clot formation in human plasma. J Biol Chem 2013; 288:28283-92. [PMID: 23960083 DOI: 10.1074/jbc.m113.493122] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Staphylococcus aureus secretes coagulase (Coa) and von Willebrand factor-binding protein (vWbp) to activate host prothrombin and form fibrin cables, thereby promoting the establishment of infectious lesions. The D1-D2 domains of Coa and vWbp associate with, and non-proteolytically activate prothrombin. Moreover, Coa encompasses C-terminal tandem repeats for binding to fibrinogen, whereas vWbp has been reported to associate with von Willebrand factor and fibrinogen. Here we used affinity chromatography with non-catalytic Coa and vWbp to identify the ligands for these virulence factors in human plasma. vWbp bound to prothrombin, fibrinogen, fibronectin, and factor XIII, whereas Coa co-purified with prothrombin and fibrinogen. vWbp association with fibrinogen and factor XIII, but not fibronectin, required prothrombin and triggered the non-proteolytic activation of FXIII in vitro. Staphylococcus aureus coagulation of human plasma was associated with the recruitment of prothrombin, FXIII, and fibronectin as well as the formation of cross-linked fibrin. FXIII activity in staphylococcal clots could be attributed to thrombin-dependent proteolytic activation as well as vWbp-mediated non-proteolytic activation of FXIII zymogen.
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Affiliation(s)
- Lena Thomer
- From the Department of Microbiology, University of Chicago, Chicago, Illinois 60637
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15
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Bacterial plasminogen receptors utilize host plasminogen system for effective invasion and dissemination. J Biomed Biotechnol 2012; 2012:482096. [PMID: 23118509 PMCID: PMC3477821 DOI: 10.1155/2012/482096] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 07/24/2012] [Accepted: 08/13/2012] [Indexed: 01/06/2023] Open
Abstract
In order for invasive pathogens to migrate beyond the site of infection, host physiological barriers such as the extracellular matrix, the basement membrane, and encapsulating fibrin network must be degraded. To circumvent these impediments, proteolytic enzymes facilitate the dissemination of the microorganism. Recruitment of host proteases to the bacterial surface represents a particularly effective mechanism for enhancing invasiveness. Plasmin is a broad spectrum serine protease that degrades fibrin, extracellular matrices, and connective tissue. A large number of pathogens express plasminogen receptors which immobilize plasmin(ogen) on the bacterial surface. Surface-bound plasminogen is then activated by plasminogen activators to plasmin through limited proteolysis thus triggering the development of a proteolytic surface on the bacteria and eventually assisting the spread of bacteria. The host hemostatic system plays an important role in systemic infection. The interplay between hemostatic processes such as coagulation and fibrinolysis and the inflammatory response constitutes essential components of host defense and bacterial invasion. The goal of this paper is to highlight mechanisms whereby pathogenic bacteria, by engaging surface receptors, utilize and exploit the host plasminogen and fibrinolytic system for the successful dissemination within the host.
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16
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Coagulation, an ancestral serine protease cascade, exerts a novel function in early immune defense. Blood 2011; 118:2589-98. [PMID: 21613262 DOI: 10.1182/blood-2011-02-337568] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Phylogenetically conserved serine protease cascades play an important role in invertebrate and vertebrate immunity. The mammalian coagulation system can be traced back some 400 million years and shares homology with ancestral serine proteinase cascades that are involved in, for example, Toll receptor signaling in insects and release of antimicrobial peptides during hemolymph clotting. In the present study, we show that the induction of coagulation by bacteria leads to immobilization and killing of Streptococcus pyogenes bacteria inside the clot. The entrapment is mediated via cross-linking of bacteria to fibrin fibers by the action of coagulation factor XIII (fXIII), an evolutionarily conserved transglutaminase. In a streptococcal skin infection model, fXIII(-/-) mice developed severe signs of pathologic inflammation at the local site of infection, and fXIII treatment of wild-type animals dampened bacterial dissemination during early infection. Bacterial killing and cross-linking to fibrin networks was also detected in tissue biopsies from patients with streptococcal necrotizing fasciitis, supporting the concept that coagulation is part of the early innate immune system.
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17
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Murphy EC, Mörgelin M, Cooney JC, Frick IM. Interaction of Bacteroides fragilis and Bacteroides thetaiotaomicron with the kallikrein-kinin system. MICROBIOLOGY-SGM 2011; 157:2094-2105. [PMID: 21527472 PMCID: PMC3167891 DOI: 10.1099/mic.0.046862-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Many bacterial pathogens interfere with the contact system (kallikrein-kinin system) in human plasma. Activation of this system has two consequences: cleavage of high-molecular-mass kininogen (HK) resulting in release of the potent proinflammatory peptide bradykinin, and initiation of the intrinsic pathway of coagulation. In this study, two species of the Gram-negative anaerobic commensal organism Bacteroides, namely Bacteroides fragilis and Bacteroides thetaiotaomicron, were found to bind HK and fibrinogen, the major clotting protein, from human plasma as shown by immunoelectron microscopy and Western blot analysis. In addition, these Bacteroides species were capable of activating the contact system at its surface leading to a significant prolongation of the intrinsic coagulation time and also to the release of bradykinin. Members of the genus Bacteroides have been known to act as opportunistic pathogens outside the gut, with B. fragilis being the most common isolate from clinical infections, such as intra-abdominal abscesses and bacteraemia. The present results thus provide more insight into how Bacteroides species cause infection.
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Affiliation(s)
- Elizabeth C Murphy
- Department of Life Sciences and Materials and Surface Science Institute, University of Limerick, Limerick, Ireland.,Department of Clinical Sciences, Lund, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden
| | - Matthias Mörgelin
- Department of Clinical Sciences, Lund, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden
| | - Jakki C Cooney
- Department of Life Sciences and Materials and Surface Science Institute, University of Limerick, Limerick, Ireland
| | - Inga-Maria Frick
- Department of Clinical Sciences, Lund, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden
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18
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Tillmann HL, McHutchison JG. Use of thrombopoietic agents for the thrombocytopenia of liver disease. Semin Hematol 2011; 47:266-73. [PMID: 20620438 DOI: 10.1053/j.seminhematol.2010.04.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Thrombocytopenia can be a sign of advanced liver disease. This complicates the management of these patients, as patients with advanced liver disease frequently need therapeutic interventions, which are associated with an increased risk of bleeding. Thrombocytopenia may even be more pronounced in patients with hepatitis C virus (HCV) infection. This can limit current and future treatments for HCV, which remains based on interferon therapy, and this therapy can worsen thrombocytopenia. Thus, the ability to increase platelets to higher and safer levels would be desirable, but no treatment has yet been proven effective and safe in this setting. The small molecule thrombopoietin mimetic, eltrombopag, has demonstrated a dose-response increase in platelet counts in a phase II study in HCV patients without significant side effects, allowing initiation and completion of a 12-week course of pegylated interferon plus ribavirin in 36%, 53%, and 65% of patients receiving 30 mg, 50 mg, or 75 mg eltrombopag daily, respectively, compared to only 6% in the placebo arm. A current phase III study is currently evaluating whether this treatment allows successful outcomes and sustained viral eradication.
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Affiliation(s)
- Hans L Tillmann
- Duke Clinical Research Institute, Duke University Medical Center, Durham, NC 27715-7969, USA.
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19
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Histidine-rich glycoprotein promotes bacterial entrapment in clots and decreases mortality in a mouse model of sepsis. Blood 2010; 116:2365-72. [DOI: 10.1182/blood-2010-02-271858] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Streptococcus pyogenes is a significant bacterial pathogen in humans. In this study, histidine-rich glycoprotein (HRG), an abundant plasma protein, was found to kill S pyogenes. Furthermore, S pyogenes grew more efficiently in HRG-deficient plasma, and clots formed in this plasma were significantly less effective at bacterial entrapment and killing. HRG-deficient mice were strikingly more susceptible to S pyogenes infection. These animals failed to control the infection at the local subcutaneous site, and abscess formation and inflammation were diminished compared with control animals. As a result, bacterial dissemination occurred more rapidly in HRG-deficient mice, and they died earlier and with a significantly higher mortality rate than control animals. HRG-deficient mice supplemented with purified HRG gave the same phenotype as control animals, demonstrating that the lack of HRG was responsible for the increased susceptibility. The results demonstrate a previously unappreciated role for HRG as a regulator of inflammation and in the defense at the local site of bacterial infection.
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20
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Oehmcke S, Shannon O, Mörgelin M, Herwald H. Streptococcal M proteins and their role as virulence determinants. Clin Chim Acta 2010; 411:1172-80. [PMID: 20452338 DOI: 10.1016/j.cca.2010.04.032] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 04/30/2010] [Indexed: 01/08/2023]
Abstract
Group A streptococci (GAS, Streptococcus pyogenes) are exclusive human pathogens that have been extensively studied for many decades. The spectrum of diseases caused by these bacteria ranges from uncomplicated and superficial to severe and invasive infections. In order to give rise to these complications, GAS have evolved a number of surface-bound and secreted virulence factors, of which the M proteins are probably the best characterized. Evidence has emerged that M proteins are multifunctional pathogenic determinants, and over the years many interactions between M proteins and the human host have been reported. The present review article aims to present a state-of-the-art overview of the most important virulence mechanisms employed by M proteins to trigger disease.
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Affiliation(s)
- Sonja Oehmcke
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden.
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21
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Treatment of invasive streptococcal infection with a peptide derived from human high-molecular weight kininogen. Blood 2009; 114:444-51. [PMID: 19433860 DOI: 10.1182/blood-2008-10-182527] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sepsis and septic shock remain an important medical problem, emphasizing the need to identify novel therapeutic opportunities. Hypovolemic hypotension, coagulation dysfunction, disturbed microcirculation, and multiorgan failure resulting from vascular leakage are often observed in these severe conditions. In the present study, we find that HKH20, a peptide derived from human high molecular weight kininogen (HK), down-regulates inflammatory reactions caused by Streptococcus pyogenes in a mouse model of sepsis. HK is a component of the pro-inflammatory and pro-coagulant contact system. Activation of the contact system in the bloodstream by S pyogenes leads to massive tissue damage in the lungs of the infected mice, which eventually results in the death of the animals. HKH20 inhibits activation of the contact system and protects mice with invasive S pyogenes infection from lung damage. In combination with clindamycin treatment, the peptide also significantly prolongs the survival of infected mice.
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Cunningham MW. Pathogenesis of Group A Streptococcal Infections and Their Sequelae. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 609:29-42. [PMID: 18193655 DOI: 10.1007/978-0-387-73960-1_3] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Madeleine W Cunningham
- University of Oklahoma Health Sciences Center, Biomedical Research Center, Oklahoma City, OK 73104, USA.
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Påhlman LI, Marx PF, Mörgelin M, Lukomski S, Meijers JCM, Herwald H. Thrombin-activatable Fibrinolysis Inhibitor Binds to Streptococcus pyogenes by Interacting with Collagen-like Proteins A and B. J Biol Chem 2007; 282:24873-81. [PMID: 17553807 DOI: 10.1074/jbc.m610015200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Regulation of proteolysis is a critical element of the host immune system and plays an important role in the induction of pro- and anti-inflammatory reactions in response to infection. Some bacterial species take advantage of these processes and recruit host proteinases to their surface in order to counteract the host attack. Here we show that Thrombin-activatable Fibrinolysis Inhibitor (TAFI), a zinc-dependent procarboxypeptidase, binds to the surface of group A streptococci of an M41 serotype. The interaction is mediated by the streptococcal collagen-like surface proteins A and B (SclA and SclB), and the streptococcal-associated TAFI is then processed at the bacterial surface via plasmin and thrombin-thrombomodulin. These findings suggest an important role for TAFI in the modulation of host responses by streptococci.
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Affiliation(s)
- Lisa I Påhlman
- Department of Clinical Sciences, Section for Clinical and Experimental Infection Medicine, Lund University, SE-22184 Lund, Sweden.
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24
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Pietrocola G, Visai L, Valtulina V, Vignati E, Rindi S, Arciola CR, Piazza R, Speziale P. Multiple Interactions of FbsA, a Surface Protein from Streptococcus agalactiae, with Fibrinogen: Affinity, Stoichiometry, and Structural Characterization. Biochemistry 2006; 45:12840-52. [PMID: 17042502 DOI: 10.1021/bi060696u] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Streptococcus agalactiae is an etiological agent of several infective diseases in humans. We previously demonstrated that FbsA, a fibrinogen-binding protein expressed by this bacterium, elicits a fibrinogen-dependent aggregation of platelets. In the present communication, we show that the binding of FbsA to fibrinogen is specific and saturable, and that the FbsA-binding site resides in the D region of fibrinogen. In accordance with the repetitive nature of the protein, we found that FbsA contains multiple binding sites for fibrinogen. By using several biophysical methods, we provide evidence that the addition of FbsA induces extensive fibrinogen aggregation and has noticeable effects on thrombin-catalyzed fibrin clot formation. Fibrinogen aggregation was also found to depend on FbsA concentration and on the number of FbsA repeat units. Scanning electron microscopy evidentiated that, while fibrin clot is made of a fine fibrillar network, FbsA-induced Fbg aggregates consist of thicker fibers organized in a cage-like structure. The structural difference of the two structures was further indicated by the diverse immunological reactivity and capability to bind tissue-type plasminogen activator or plasminogen. The mechanisms of FbsA-induced fibrinogen aggregation and fibrin polymerization followed distinct pathways since Fbg assembly was not inhibited by GPRP, a specific inhibitor of fibrin polymerization. This finding was supported by the different sensitivity of the aggregates to the disruptive effects of urea and guanidine hydrochloride. We suggest that FbsA and fibrinogen play complementary roles in contributing to thrombogenesis associated with S. agalactiae infection.
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Affiliation(s)
- Giampiero Pietrocola
- Department of Biochemistry, University of Pavia, Viale Taramelli 3/B 27100 Pavia, Italy
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26
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Gebbink MFBG, Claessen D, Bouma B, Dijkhuizen L, Wösten HAB. Amyloids--a functional coat for microorganisms. Nat Rev Microbiol 2005; 3:333-41. [PMID: 15806095 DOI: 10.1038/nrmicro1127] [Citation(s) in RCA: 214] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Amyloids are filamentous protein structures approximately 10 nm wide and 0.1-10 mum long that share a structural motif, the cross-beta structure. These fibrils are usually associated with degenerative diseases in mammals. However, recent research has shown that these proteins are also expressed on bacterial and fungal cell surfaces. Microbial amyloids are important in mediating mechanical invasion of abiotic and biotic substrates. In animal hosts, evidence indicates that these protein structures also contribute to colonization by activating host proteases that are involved in haemostasis, inflammation and remodelling of the extracellular matrix. Activation of proteases by amyloids is also implicated in modulating blood coagulation, resulting in potentially life-threatening complications.
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Affiliation(s)
- Martijn F B G Gebbink
- Department of Haematology, Thrombosis and Haemostasis Laboratory, Institute of Biomembranes, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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27
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Herwald H, Cramer H, Mörgelin M, Russell W, Sollenberg U, Norrby-Teglund A, Flodgaard H, Lindbom L, Björck L. M protein, a classical bacterial virulence determinant, forms complexes with fibrinogen that induce vascular leakage. Cell 2004; 116:367-79. [PMID: 15016372 DOI: 10.1016/s0092-8674(04)00057-1] [Citation(s) in RCA: 248] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2003] [Revised: 12/18/2003] [Accepted: 12/18/2003] [Indexed: 11/26/2022]
Abstract
Increased vascular permeability is a key feature of inflammatory conditions. In severe infections, leakage of plasma from the vasculature induces a life-threatening hypotension. Streptococcus pyogenes, a major human bacterial pathogen, causes a toxic shock syndrome (STSS) characterized by excessive plasma leakage and multi-organ failure. Here we find that M protein, released from the streptococcal surface, forms complexes with fibrinogen, which by binding to beta2 integrins of neutrophils, activate these cells. As a result, neutrophils release heparin binding protein, an inflammatory mediator inducing vascular leakage. In mice, injection of M protein or subcutaneous infection with S. pyogenes causes severe pulmonary damage characterized by leakage of plasma and blood cells. These lesions were prevented by treatment with a beta2 integrin antagonist. In addition, M protein/fibrinogen complexes were identified in tissue biopsies from a patient with necrotizing fasciitis and STSS, further underlining the pathogenic significance of such complexes in severe streptococcal infections.
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Affiliation(s)
- Heiko Herwald
- Department of Cell and Molecular Biology, Lund University, Tornavägen 10, S-221 84 Lund, Sweden.
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