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Strnad M, Koizumi N, Nakamura S, Vancová M, Rego ROM. It's not all about flagella - sticky invasion by pathogenic spirochetes. Trends Parasitol 2024; 40:378-385. [PMID: 38523038 DOI: 10.1016/j.pt.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/07/2024] [Accepted: 03/12/2024] [Indexed: 03/26/2024]
Abstract
Pathogenic spirochetes cause a range of serious human diseases such as Lyme disease (LD), syphilis, leptospirosis, relapsing fever (RF), and periodontal disease. Motility is a critical virulence factor for spirochetes. From the mechanical perspective of the infection, it has been widely believed that flagella are the sole key players governing the migration and dissemination of these pathogens in the host. Here, we highlight the important contribution of spirochetal surface-exposed adhesive molecules and their dynamic interactions with host molecules in the process of infection, specifically in spirochetal swimming and crawling migration. We believe that these recent findings overturn the prevailing view depicting the spirochetal body to be just an inert elastic bag, which does not affect spirochetal cell locomotion.
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Affiliation(s)
- Martin Strnad
- Institute of Parasitology, Biology Centre CAS, Branišovská 31, 37005, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic.
| | - Nobuo Koizumi
- Department of Bacteriology I, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Shuichi Nakamura
- Department of Applied Physics, Graduate School of Engineering, Tohoku University, 6-6-05 Aoba, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Marie Vancová
- Institute of Parasitology, Biology Centre CAS, Branišovská 31, 37005, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic
| | - Ryan O M Rego
- Institute of Parasitology, Biology Centre CAS, Branišovská 31, 37005, České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 1760, 37005, České Budějovice, Czech Republic
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2
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Damm AS, Reyer F, Langhoff L, Lin YP, Falcone FH, Kraiczy P. Multifunctional interaction of CihC/FbpC orthologs of relapsing fever spirochetes with host-derived proteins involved in adhesion, fibrinolysis, and complement evasion. Front Immunol 2024; 15:1390468. [PMID: 38726006 PMCID: PMC11079166 DOI: 10.3389/fimmu.2024.1390468] [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: 02/23/2024] [Accepted: 04/01/2024] [Indexed: 05/12/2024] Open
Abstract
Introduction Relapsing fever (RF) remains a neglected human disease that is caused by a number of diverse pathogenic Borrelia (B.) species. Characterized by high cell densities in human blood, relapsing fever spirochetes have developed plentiful strategies to avoid recognition by the host defense mechanisms. In this scenario, spirochetal lipoproteins exhibiting multifunctional binding properties in the interaction with host-derived molecules are known to play a key role in adhesion, fibrinolysis and complement activation. Methods Binding of CihC/FbpC orthologs to different human proteins and conversion of protein-bound plasminogen to proteolytic active plasmin were examined by ELISA. To analyze the inhibitory capacity of CihC/FbpC orthologs on complement activation, a microtiter-based approach was performed. Finally, AlphaFold predictions were utilized to identified the complement-interacting residues. Results and discussion Here, we elucidate the binding properties of CihC/FbpC-orthologs from distinct RF spirochetes including B. parkeri, B. hermsii, B. turicatae, and B. recurrentis to human fibronectin, plasminogen, and complement component C1r. All CihC/FbpC-orthologs displayed similar binding properties to fibronectin, plasminogen, and C1r, respectively. Functional studies revealed a dose dependent binding of plasminogen to all borrelial proteins and conversion to active plasmin. The proteolytic activity of plasmin was almost completely abrogated by tranexamic acid, indicating that lysine residues are involved in the interaction with this serine protease. In addition, a strong inactivation capacity toward the classical pathway could be demonstrated for the wild-type CihC/FbpC-orthologs as well as for the C-terminal CihC fragment of B. recurrentis. Pre-incubation of human serum with borrelial molecules except CihC/FbpC variants lacking the C-terminal region protected serum-susceptible Borrelia cells from complement-mediated lysis. Utilizing AlphaFold2 predictions and existing crystal structures, we mapped the putative key residues involved in C1r binding on the CihC/FbpC orthologs attempting to explain the relatively small differences in C1r binding affinity despite the substitutions of key residues. Collectively, our data advance the understanding of the multiple binding properties of structural and functional highly similar molecules of relapsing fever spirochetes proposed to be involved in pathogenesis and virulence.
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Affiliation(s)
- Ann-Sophie Damm
- Institute of Medical Microbiology and Infection Control, University Hospital of Frankfurt, Goethe University Frankfurt, Frankfurt, Germany
| | - Flavia Reyer
- Institute of Medical Microbiology and Infection Control, University Hospital of Frankfurt, Goethe University Frankfurt, Frankfurt, Germany
| | - Luisa Langhoff
- Institute of Medical Microbiology and Infection Control, University Hospital of Frankfurt, Goethe University Frankfurt, Frankfurt, Germany
| | - Yi-Pin Lin
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA, United States
| | - Franco Harald Falcone
- Institute of Parasitology, Biomedical Research Center Seltersberg, Justus Liebig University Giessen, Giessen, Germany
| | - Peter Kraiczy
- Institute of Medical Microbiology and Infection Control, University Hospital of Frankfurt, Goethe University Frankfurt, Frankfurt, Germany
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3
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Strnad M, Rudenko N, Rego RO. Pathogenicity and virulence of Borrelia burgdorferi. Virulence 2023; 14:2265015. [PMID: 37814488 PMCID: PMC10566445 DOI: 10.1080/21505594.2023.2265015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 09/25/2023] [Indexed: 10/11/2023] Open
Abstract
Infection with Borrelia burgdorferi often triggers pathophysiologic perturbations that are further augmented by the inflammatory responses of the host, resulting in the severe clinical conditions of Lyme disease. While our apprehension of the spatial and temporal integration of the virulence determinants during the enzootic cycle of B. burgdorferi is constantly being improved, there is still much to be discovered. Many of the novel virulence strategies discussed in this review are undetermined. Lyme disease spirochaetes must surmount numerous molecular and mechanical obstacles in order to establish a disseminated infection in a vertebrate host. These barriers include borrelial relocation from the midgut of the feeding tick to its body cavity and further to the salivary glands, deposition to the skin, haematogenous dissemination, extravasation from blood circulation system, evasion of the host immune responses, localization to protective niches, and establishment of local as well as distal infection in multiple tissues and organs. Here, the various well-defined but also possible novel strategies and virulence mechanisms used by B. burgdorferi to evade obstacles laid out by the tick vector and usually the mammalian host during colonization and infection are reviewed.
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Affiliation(s)
- Martin Strnad
- Biology Centre CAS, Institute of Parasitology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská, Czech Republic
| | - Natalie Rudenko
- Biology Centre CAS, Institute of Parasitology, České Budějovice, Czech Republic
| | - Ryan O.M. Rego
- Biology Centre CAS, Institute of Parasitology, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská, Czech Republic
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4
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Vaca DJ, Frenzel F, Ballhorn W, Torres SG, Leisegang MS, Günther S, Bender D, Kraiczy P, Göttig S, Kempf VAJ. Adhesion of human pathogenic bacteria to endothelial cells is facilitated by fibronectin interaction. Microbes Infect 2023; 25:105172. [PMID: 37343664 DOI: 10.1016/j.micinf.2023.105172] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 06/07/2023] [Accepted: 06/10/2023] [Indexed: 06/23/2023]
Abstract
Human pathogenic bacteria circulating in the bloodstream need to find a way to interact with endothelial cells (ECs) lining the blood vessels to infect and colonise the host. The extracellular matrix (ECM) of ECs might represent an attractive initial target for bacterial interaction, as many bacterial adhesins have reported affinities to ECM proteins, in particular to fibronectin (Fn). Here, we analysed the general role of EC-expressed Fn for bacterial adhesion. For this, we evaluated the expression levels of ECM coding genes in different ECs, revealing that Fn is the highest expressed gene and thereby, it is highly abundant in the ECM environment of ECs. The role of Fn as a mediator in bacterial cell-host adhesion was evaluated in adhesion assays of Acinetobacter baumannii, Bartonella henselae, Borrelia burgdorferi, and Staphylococcus aureus to ECs. The assays demonstrated that bacteria colocalised with Fn fibres, as observed by confocal laser scanning microscopy. Fn removal from the ECM environment (FN1 knockout ECs) diminished bacterial adherence to ECs in both static and dynamic adhesion assays to varying extents, as evaluated via absolute quantification using qPCR. Interactions between adhesins and Fn might represent the crucial step for the adhesion of human-pathogenic Gram-negative and Gram-positive bacteria targeting the ECs as a niche of infection.
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Affiliation(s)
- Diana J Vaca
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Fabienne Frenzel
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Wibke Ballhorn
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Sara Garcia Torres
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Matthias S Leisegang
- Institute for Cardiovascular Physiology, Goethe University, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany; German Center of Cardiovascular Research (DZHK), Partner Site RheinMain, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
| | - Stefan Günther
- Max Planck Institute for Heart and Lung Research, Parkstraße 1, 61231, Bad Nauheim, Germany.
| | - Daniela Bender
- Federal Institute for Vaccines and Biomedicines, Department of Virology, Paul Ehrlich Institute, Paul-Ehrlich-Straße 51-59, 63225, Langen, Germany.
| | - Peter Kraiczy
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Stephan Göttig
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
| | - Volkhard A J Kempf
- Institute of Medical Microbiology and Infection Control, Goethe University, Paul Ehrlich Straße 40, 60596, Frankfurt, Germany.
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5
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Tan X, Castellanos M, Chaconas G. Choreography of Lyme Disease Spirochete Adhesins To Promote Vascular Escape. Microbiol Spectr 2023; 11:e0125423. [PMID: 37255427 PMCID: PMC10434219 DOI: 10.1128/spectrum.01254-23] [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: 03/23/2023] [Accepted: 05/12/2023] [Indexed: 06/01/2023] Open
Abstract
The Lyme disease spirochete Borrelia burgdorferi sensu lato can cause a multitude of clinical manifestations because of its ability to disseminate into any organ system via migration through soft tissue, the lymphatic system, and the circulatory system. The latter is believed to constitute the predominant pathway for dissemination to distal sites from the inoculating tick bite. In spite of its importance, the hematogenous dissemination process remains largely uncharacterized, particularly due to difficulties studying this process in a living host and the lack of an in vitro system that recapitulates animal infection. In the current work, we provide the first information regarding the stage of the vascular transmigration pathway where three important adhesins function during invasion of mouse knee joint peripheral tissue from postcapillary venules. Using intravital imaging coupled with genetic experiments employing sequential double infection, we show a complex temporal choreography of P66, decorin binding proteins (DbpA/B), and outer surface protein C (OspC) at discrete steps along the pathway of vascular escape, underscoring the importance of B. burgdorferi adhesins in hematogenous dissemination in the mouse knee joint and the complexity of vascular transmigration by a disseminating pathogen. IMPORTANCE Lyme disease is caused by the spirochete Borrelia burgdorferi, which is transmitted by a bite from an infected tick. Disease development involves a complex series of host-pathogen interactions as well as dissemination of the infecting organisms to sites distal to the original tick bite. The predominant pathway for this is believed to be hematogenous dissemination. The mechanism by which the spirochetes escape circulation is unknown. Here, using intravital microscopy, where the Lyme spirochete can be observed in a living mouse, we have studied the stage in the vascular escape process where each of three surface adhesins functions to facilitate escape of the spirochete from postcapillary venules to invade mouse knee joint peripheral tissue. A complex pattern of involvement at various locations in the multistage process is described using a unique experimental approach that is applicable to other disseminating pathogens.
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Affiliation(s)
- Xi Tan
- Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada
| | - Mildred Castellanos
- Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada
| | - George Chaconas
- Department of Biochemistry & Molecular Biology, University of Calgary, Calgary, Alberta, Canada
- Department of Microbiology, Immunology & Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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6
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Flynn CD, Sandomierski M, Kim K, Lewis J, Lloyd V, Ignaszak A. Electrochemical Detection of Borrelia burgdorferi Using a Biomimetic Flow Cell System. ACS MEASUREMENT SCIENCE AU 2023; 3:208-216. [PMID: 37360035 PMCID: PMC10288608 DOI: 10.1021/acsmeasuresciau.3c00004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/11/2023] [Accepted: 03/13/2023] [Indexed: 06/28/2023]
Abstract
Lyme disease, caused by infection with pathogenic Borrelia bacteria, has emerged as a pervasive illness throughout North America and many other regions of the world in recent years, owing in part to climate-mediated habitat expansion of the tick vectors. Standard diagnostic testing has remained largely unchanged over the past several decades and is indirect, relying on detection of antibodies against the Borrelia pathogen, rather than detection of the pathogen itself. The development of new rapid, point-of-care tests for Lyme disease that directly detects the pathogen could drastically improve patient health by enabling faster and more frequent testing that could better inform patient treatment. Here, we describe a proof-of-concept electrochemical sensing approach to the detection of the Lyme disease-causing bacteria, which utilizes a biomimetic electrode to interact with the Borrelia bacteria that induce impedance alterations. In addition, the catch-bond mechanism between bacterial BBK32 protein and human fibronectin protein, which exhibits improved bond strength with increased tensile force, is tested within an electrochemical injection flow-cell to achieve Borrelia detection under shear stress.
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Affiliation(s)
- Connor D. Flynn
- Department
of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Department
of Chemistry, University of Toronto, Toronto, ON M5S 3G8, Canada
- Department
of Chemistry, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Mariusz Sandomierski
- Department
of Chemistry, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
- Institute
of Chemical Technology and Engineering, Poznan University of Technology, ul. Berdychowo 4, 60-965 Poznań, Poland
| | - Kelly Kim
- Department
of Chemistry, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Julie Lewis
- Department
of Biology, Mount Allison University, Sackville, NB E4L 1E2, Canada
| | - Vett Lloyd
- Department
of Biology, Mount Allison University, Sackville, NB E4L 1E2, Canada
| | - Anna Ignaszak
- Department
of Chemistry, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
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7
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Grassmann AA, Tokarz R, Golino C, McLain MA, Groshong AM, Radolf JD, Caimano MJ. BosR and PlzA reciprocally regulate RpoS function to sustain Borrelia burgdorferi in ticks and mammals. J Clin Invest 2023; 133:e166710. [PMID: 36649080 PMCID: PMC9974103 DOI: 10.1172/jci166710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 01/10/2023] [Indexed: 01/18/2023] Open
Abstract
The RNA polymerase alternative σ factor RpoS in Borrelia burgdorferi (Bb), the Lyme disease pathogen, is responsible for programmatic-positive and -negative gene regulation essential for the spirochete's dual-host enzootic cycle. RpoS is expressed during tick-to-mammal transmission and throughout mammalian infection. Although the mammalian-phase RpoS regulon is well described, its counterpart during the transmission blood meal is unknown. Here, we used Bb-specific transcript enrichment by tick-borne disease capture sequencing (TBDCapSeq) to compare the transcriptomes of WT and ΔrpoS Bb in engorged nymphs and following mammalian host-adaptation within dialysis membrane chambers. TBDCapSeq revealed dramatic changes in the contours of the RpoS regulon within ticks and mammals and further confirmed that RpoS-mediated repression is specific to the mammalian-phase of Bb's enzootic cycle. We also provide evidence that RpoS-dependent gene regulation, including repression of tick-phase genes, is required for persistence in mice. Comparative transcriptomics of engineered Bb strains revealed that the Borrelia oxidative stress response regulator (BosR), a noncanonical Fur family member, and the cyclic diguanosine monophosphate (c-di-GMP) effector PlzA reciprocally regulate the function of RNA polymerase complexed with RpoS. BosR is required for RpoS-mediated transcription activation and repression in addition to its well-defined role promoting transcription of rpoS by the RNA polymerase alternative σ factor RpoN. During transmission, ligand-bound PlzA antagonizes RpoS-mediated repression, presumably acting through BosR.
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Affiliation(s)
| | - Rafal Tokarz
- Center for Infection and Immunity and
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Caroline Golino
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
| | | | - Ashley M. Groshong
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
- Department of Pediatrics
| | - Justin D. Radolf
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
- Department of Pediatrics
- Department of Molecular Biology and Biophysics
- Department of Genetics and Genome Sciences, and
- Department of Immunology, UConn Health, Farmington, Connecticut, USA
| | - Melissa J. Caimano
- Department of Medicine, UConn Health, Farmington, Connecticut, USA
- Department of Pediatrics
- Department of Molecular Biology and Biophysics
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8
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A Live Cell Imaging Microfluidic Model for Studying Extravasation of Bloodborne Bacterial Pathogens. Cell Microbiol 2022. [DOI: 10.1155/2022/3130361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bacteria that migrate (extravasate) out of the bloodstream during vascular dissemination can cause secondary infections in many tissues and organs, including the brain, heart, liver, joints, and bone with clinically serious and sometimes fatal outcomes. The mechanisms by which bacteria extravasate through endothelial barriers in the face of blood flow-induced shear stress are poorly understood, in part because individual bacteria are rarely observed traversing endothelia in vivo, and in vitro model systems inadequately mimic the vascular environment. To enable the study of bacterial extravasation mechanisms, we developed a transmembrane microfluidics device mimicking human blood vessels. Fast, quantitative, three-dimensional live cell imaging in this system permitted single-cell resolution measurement of the Lyme disease bacterium Borrelia burgdorferi transmigrating through monolayers of primary human endothelial cells under physiological shear stress. This cost-effective, flexible method was 10,000 times more sensitive than conventional plate reader-based methods for measuring transendothelial migration. Validation studies confirmed that B. burgdorferi transmigrate actively and strikingly do so at similar rates under static and physiological flow conditions. This method has significant potential for future studies of B. burgdorferi extravasation mechanisms, as well as the transendothelial migration mechanisms of other disseminating bloodborne pathogens.
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9
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Yuste RA, Muenkel M, Axarlis K, Gómez Benito MJ, Reuss A, Blacker G, Tal MC, Kraiczy P, Bastounis EE. Borrelia burgdorferi modulates the physical forces and immunity signaling in endothelial cells. iScience 2022; 25:104793. [PMID: 35992087 PMCID: PMC9389243 DOI: 10.1016/j.isci.2022.104793] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 06/09/2022] [Accepted: 07/13/2022] [Indexed: 12/04/2022] Open
Abstract
Borrelia burgdorferi (Bb), a vector-borne bacterial pathogen and the causative agent of Lyme disease, can spread to distant tissues in the human host by traveling in and through monolayers of endothelial cells (ECs) lining the vasculature. To examine whether Bb alters the physical forces of ECs to promote its dissemination, we exposed ECs to Bb and observed a sharp and transient increase in EC traction and intercellular forces, followed by a prolonged decrease in EC motility and physical forces. All variables returned to baseline at 24 h after exposure. RNA sequencing analysis revealed an upregulation of innate immune signaling pathways during early but not late Bb exposure. Exposure of ECs to heat-inactivated Bb recapitulated only the early weakening of EC mechanotransduction. The differential responses to live versus heat-inactivated Bb indicate a tight interplay between innate immune signaling and physical forces in host ECs and suggest their active modulation by Bb. Early exposure to Borrelia decreases endothelial cell motility and physical forces Early exposure to Borrelia also upregulates the host’s innate immune signaling pathways Host cell mechanics and signaling return to steady state at late exposure times Exposure to dead bacteria steadily reduces motility and physical forces of host cells
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10
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Booth CE, Powell-Pierce AD, Skare JT, Garcia BL. Borrelia miyamotoi FbpA and FbpB Are Immunomodulatory Outer Surface Lipoproteins With Distinct Structures and Functions. Front Immunol 2022; 13:886733. [PMID: 35693799 PMCID: PMC9186069 DOI: 10.3389/fimmu.2022.886733] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/19/2022] [Indexed: 01/04/2023] Open
Abstract
Pathogens that traffic in the blood of their hosts must employ mechanisms to evade the host innate immune system, including the complement cascade. The Lyme disease spirochete, Borreliella burgdorferi, has evolved numerous outer membrane lipoproteins that interact directly with host proteins. Compared to Lyme disease-associated spirochetes, relatively little is known about how an emerging tick-borne spirochetal pathogen, Borrelia miyamotoi, utilizes surface lipoproteins to interact with a human host. B. burgdorferi expresses the multifunctional lipoprotein, BBK32, that inhibits the classical pathway of complement through interaction with the initiating protease C1r, and also interacts with fibronectin using a separate intrinsically disordered domain. B. miyamotoi encodes two separate bbk32 orthologs denoted fbpA and fbpB; however, the activities of these proteins are unknown. Here, we show that B. miyamotoi FbpA binds human fibronectin in a manner similar to B. burgdorferi BBK32, whereas FbpB does not. FbpA and FbpB both bind human complement C1r and protect a serum-sensitive B. burgdorferi strain from complement-mediated killing, but surprisingly, differ in their ability to recognize activated C1r versus zymogen states of C1r. To better understand the observed differences in C1r recognition and inhibition properties, high-resolution X-ray crystallography structures were solved of the C1r-binding regions of B. miyamotoi FbpA and FbpB at 1.9Å and 2.1Å, respectively. Collectively, these data suggest that FbpA and FbpB have partially overlapping functions but are functionally and structurally distinct. The data presented herein enhances our overall understanding of how bloodborne pathogens interact with fibronectin and modulate the complement system.
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Affiliation(s)
- Charles E Booth
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
| | - Alexandra D Powell-Pierce
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Jon T Skare
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Brandon L Garcia
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, United States
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11
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Mechanical Forces Govern Interactions of Host Cells with Intracellular Bacterial Pathogens. Microbiol Mol Biol Rev 2022; 86:e0009420. [PMID: 35285720 PMCID: PMC9199418 DOI: 10.1128/mmbr.00094-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
To combat infectious diseases, it is important to understand how host cells interact with bacterial pathogens. Signals conveyed from pathogen to host, and vice versa, may be either chemical or mechanical. While the molecular and biochemical basis of host-pathogen interactions has been extensively explored, relatively less is known about mechanical signals and responses in the context of those interactions. Nevertheless, a wide variety of bacterial pathogens appear to have developed mechanisms to alter the cellular biomechanics of their hosts in order to promote their survival and dissemination, and in turn many host responses to infection rely on mechanical alterations in host cells and tissues to limit the spread of infection. In this review, we present recent findings on how mechanical forces generated by host cells can promote or obstruct the dissemination of intracellular bacterial pathogens. In addition, we discuss how in vivo extracellular mechanical signals influence interactions between host cells and intracellular bacterial pathogens. Examples of such signals include shear stresses caused by fluid flow over the surface of cells and variable stiffness of the extracellular matrix on which cells are anchored. We highlight bioengineering-inspired tools and techniques that can be used to measure host cell mechanics during infection. These allow for the interrogation of how mechanical signals can modulate infection alongside biochemical signals. We hope that this review will inspire the microbiology community to embrace those tools in future studies so that host cell biomechanics can be more readily explored in the context of infection studies.
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12
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Recombinant FimH Adhesin Demonstrates How the Allosteric Catch Bond Mechanism Can Support Fast and Strong Bacterial Attachment in the Absence of Shear. J Mol Biol 2022; 434:167681. [PMID: 35697293 DOI: 10.1016/j.jmb.2022.167681] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 06/07/2022] [Accepted: 06/07/2022] [Indexed: 11/23/2022]
Abstract
The FimH protein of Escherichia coli is a model two-domain adhesin that is able to mediate an allosteric catch bond mechanism of bacterial cell attachment, where the mannose-binding lectin domain switches from an 'inactive' conformation with fast binding to mannose to an 'active' conformation with slow detachment from mannose. Because mechanical tensile force favors separation of the domains and, thus, FimH activation, it has been thought that the catch bonds can only be manifested in a fluidic shear-dependent mode of adhesion. Here, we used recombinant FimH variants with a weakened inter-domain interaction and show that a fast and sustained allosteric activation of FimH can also occur under static, non-shear conditions. Moreover, it appears that lectin domain conformational activation happens intrinsically at a constant rate, independently from its ability to interact with the pilin domain or mannose. However, the latter two factors control the rate of FimH deactivation. Thus, the allosteric catch bond mechanism can be a much broader phenomenon involved in both fast and strong cell-pathogen attachments under a broad range of hydrodynamic conditions. This concept that allostery can enable more effective receptor-ligand interactions is fundamentally different from the conventional wisdom that allostery provides a mechanism to turn binding off under specific conditions.
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13
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Garrigues RJ, Powell-Pierce AD, Hammel M, Skare JT, Garcia BL. A Structural Basis for Inhibition of the Complement Initiator Protease C1r by Lyme Disease Spirochetes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2021; 207:2856-2867. [PMID: 34759015 PMCID: PMC8612984 DOI: 10.4049/jimmunol.2100815] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 09/23/2021] [Indexed: 12/26/2022]
Abstract
Complement evasion is a hallmark of extracellular microbial pathogens such as Borrelia burgdorferi, the causative agent of Lyme disease. Lyme disease spirochetes express nearly a dozen outer surface lipoproteins that bind complement components and interfere with their native activities. Among these, BBK32 is unique in its selective inhibition of the classical pathway. BBK32 blocks activation of this pathway by selectively binding and inhibiting the C1r serine protease of the first component of complement, C1. To understand the structural basis for BBK32-mediated C1r inhibition, we performed crystallography and size-exclusion chromatography-coupled small angle X-ray scattering experiments, which revealed a molecular model of BBK32-C in complex with activated human C1r. Structure-guided site-directed mutagenesis was combined with surface plasmon resonance binding experiments and assays of complement function to validate the predicted molecular interface. Analysis of the structures shows that BBK32 inhibits activated forms of C1r by occluding substrate interaction subsites (i.e., S1 and S1') and reveals a surprising role for C1r B loop-interacting residues for full inhibitory activity of BBK32. The studies reported in this article provide for the first time (to our knowledge) a structural basis for classical pathway-specific inhibition by a human pathogen.
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Affiliation(s)
- Ryan J Garrigues
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Alexandra D Powell-Pierce
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan/College Station, TX; and
| | - Michal Hammel
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA
| | - Jon T Skare
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan/College Station, TX; and
| | - Brandon L Garcia
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC;
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14
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Borrelia burgdorferi BmpA-BBK32 and BmpA-BBA64: New Recombinant Chimeric Proteins with Potential Diagnostic Value. Pathogens 2021; 10:pathogens10060767. [PMID: 34207025 PMCID: PMC8234703 DOI: 10.3390/pathogens10060767] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 11/17/2022] Open
Abstract
Currently, the diagnosis of Lyme disease is based mostly on two-tiered serologic testing. In the new generation of immunoenzymatic assays, antigens comprise whole-cell lysates of members of the Borrelia burgdorferi sensu lato (s.l.) species complex, with the addition of selected recombinant proteins. Due to the high diversity of members of the B. burgdorferi s.l. genospecies and the low degree of conservation among the amino acid sequences of their proteins, serodiagnostic methods currently in use are not sufficient for the correct diagnosis of borreliosis. Two divalent chimeric proteins (BmpA-BBK32 and BmpA-BBA64) were expressed in Escherichia coli. Following purification by one-step metal-affinity chromatography, preparations were obtained containing milligram levels of chimeric protein exhibiting electrophoretic purity in excess of 98%. Reactivity of the new chimeric proteins with specific human IgG antibodies was preliminarily determined by Western blot. For this purpose, 20 negative sera and 20 positive sera was used. The new chimeric proteins were highly reactive with IgG antibodies contained in the serum of patients suffering from borreliosis. Moreover, no immunoreactivity of chimeric proteins was observed with antibodies in the sera of healthy people. These promising results suggest that new chimeric proteins have the potential to discriminate between positive and negative sera.
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15
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The Brilliance of Borrelia: Mechanisms of Host Immune Evasion by Lyme Disease-Causing Spirochetes. Pathogens 2021; 10:pathogens10030281. [PMID: 33801255 PMCID: PMC8001052 DOI: 10.3390/pathogens10030281] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 01/31/2023] Open
Abstract
Lyme disease (LD) has become the most common vector-borne illness in the northern hemisphere. The causative agent, Borrelia burgdorferi sensu lato, is capable of establishing a persistent infection within the host. This is despite the activation of both the innate and adaptive immune responses. B. burgdorferi utilizes several immune evasion tactics ranging from the regulation of surface proteins, tick saliva, antimicrobial peptide resistance, and the disabling of the germinal center. This review aims to cover the various methods by which B. burgdorferi evades detection and destruction by the host immune response, examining both the innate and adaptive responses. By understanding the methods employed by B. burgdorferi to evade the host immune response, we gain a deeper knowledge of B. burgdorferi pathogenesis and Lyme disease, and gain insight into how to create novel, effective treatments.
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16
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Nanomechanical mechanisms of Lyme disease spirochete motility enhancement in extracellular matrix. Commun Biol 2021; 4:268. [PMID: 33649506 PMCID: PMC7921401 DOI: 10.1038/s42003-021-01783-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 02/01/2021] [Indexed: 01/31/2023] Open
Abstract
As opposed to pathogens passively circulating in the body fluids of their host, pathogenic species within the Spirochetes phylum are able to actively coordinate their movement in the host to cause systemic infections. Based on the unique morphology and high motility of spirochetes, we hypothesized that their surface adhesive molecules might be suitably adapted to aid in their dissemination strategies. Designing a system that mimics natural environmental signals, which many spirochetes face during their infectious cycle, we observed that a subset of their surface proteins, particularly Decorin binding protein (Dbp) A/B, can strongly enhance the motility of spirochetes in the extracellular matrix of the host. Using single-molecule force spectroscopy, we disentangled the mechanistic details of DbpA/B and decorin/laminin interactions. Our results show that spirochetes are able to leverage a wide variety of adhesion strategies through force-tuning transient molecular binding to extracellular matrix components, which concertedly enhance spirochetal dissemination through the host.
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17
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Bista S, Singh P, Bernard Q, Yang X, Hart T, Lin YP, Kitsou C, Singh Rana V, Zhang F, Linhardt RJ, Zhnag K, Akins DR, Hritzo L, Kim Y, Grab DJ, Dumler JS, Pal U. A Novel Laminin-Binding Protein Mediates Microbial-Endothelial Cell Interactions and Facilitates Dissemination of Lyme Disease Pathogens. J Infect Dis 2021; 221:1438-1447. [PMID: 31758693 DOI: 10.1093/infdis/jiz626] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 11/21/2019] [Indexed: 12/13/2022] Open
Abstract
Borrelia burgdorferi conserved gene products BB0406 and BB0405, members of a common B. burgdorferi paralogous gene family, share 59% similarity. Although both gene products can function as potential porins, only BB0405 is essential for infection. Here we show that, despite sequence homology and coexpression from the same operon, both proteins differ in their membrane localization attributes, antibody accessibility, and immunogenicity in mice. BB0406 is required for spirochete survival in mammalian hosts, particularly for the disseminated infection in distant organs. We identified that BB0406 interacts with laminin, one of the major constituents of the vascular basement membrane, and facilitates spirochete transmigration across host endothelial cell barriers. A better understanding of how B. burgdorferi transmigrates through dermal and tissue vascular barriers and establishes disseminated infections will contribute to the development of novel therapeutics to combat early infection.
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Affiliation(s)
- Sandhya Bista
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, USA
| | - Preeti Singh
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, USA
| | - Quentin Bernard
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, USA
| | - Xiuli Yang
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, USA
| | - Thomas Hart
- Department of Biological Science, State University of New York at Albany, Albany, New York, USA.,Division of Infectious Diseases, Wadsworth Center New York State Department of Health, Albany, New York, USA
| | - Yi-Pin Lin
- Department of Biological Science, State University of New York at Albany, Albany, New York, USA.,Department of Biomedical Science, State University of New York at Albany, Albany, New York, USA
| | - Chrysoula Kitsou
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, USA
| | - Vipin Singh Rana
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, USA
| | - Fuming Zhang
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Robert J Linhardt
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA.,Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York, USA.,Department of Biology and Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Kai Zhnag
- Oral and Craniofacial Molecular Biology, School of Dentistry, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Darrin R Akins
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Lucy Hritzo
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Yuri Kim
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Dennis J Grab
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - J Stephen Dumler
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - Utpal Pal
- Department of Veterinary Medicine, University of Maryland, College Park, Maryland, USA.,Virginia-Maryland College of Veterinary Medicine, College Park, Maryland
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18
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Chaconas G, Moriarty TJ, Skare J, Hyde JA. Live Imaging. Curr Issues Mol Biol 2020; 42:385-408. [PMID: 33310914 PMCID: PMC7946808 DOI: 10.21775/cimb.042.385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Being able to vizualize a pathogen at a site of interaction with a host is an aesthetically appealing idea and the resulting images can be both informative as well as enjoyable to view. Moreover, the approaches used to derive these images can be powerful in terms of offering data unobtainable by other methods. In this article, we review three primary modalities for live imaging Borrelia spirochetes: whole animal imaging, intravital microscopy and live cell imaging. Each method has strengths and weaknesses, which we review, as well as specific purposes for which they are optimally utilized. Live imaging borriliae is a relatively recent development and there was a need of a review to cover the area. Here, in addition to the methods themselves, we also review areas of spirochete biology that have been significantly impacted by live imaging and present a collection of images associated with the forward motion in the field driven by imaging studies.
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Affiliation(s)
- George Chaconas
- Department of Biochemistry and Molecular Biology and Department of Microbiology, Immunology and Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, T2N 4N1, Canada
| | - Tara J. Moriarty
- Faculties of Dentistry and Medicine (Laboratory Medicine and Pathobiology), University of Toronto, Toronto, Ontario, M5G 1G6, Canada
| | - Jon Skare
- Department of Microbial Pathogenesis and Immunology, Texas A & M University Health Science Center, Bryan, Texas, 77807, USA
| | - Jenny A. Hyde
- Department of Microbial Pathogenesis and Immunology, Texas A & M University Health Science Center, Bryan, Texas, 77807, USA
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19
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Abstract
Lyme disease (Lyme borreliosis) is a tick-borne, zoonosis of adults and children caused by genospecies of the Borrelia burgdorferi sensu lato complex. The ailment, widespread throughout the Northern Hemisphere, continues to increase globally due to multiple environmental factors, coupled with increased incursion of humans into habitats that harbor the spirochete. B. burgdorferi sensu lato is transmitted by ticks from the Ixodes ricinus complex. In North America, B. burgdorferi causes nearly all infections; in Europe, B. afzelii and B. garinii are most associated with human disease. The spirochete's unusual fragmented genome encodes a plethora of differentially expressed outer surface lipoproteins that play a seminal role in the bacterium's ability to sustain itself within its enzootic cycle and cause disease when transmitted to its incidental human host. Tissue damage and symptomatology (i.e., clinical manifestations) result from the inflammatory response elicited by the bacterium and its constituents. The deposition of spirochetes into human dermal tissue generates a local inflammatory response that manifests as erythema migrans (EM), the hallmark skin lesion. If treated appropriately and early, the prognosis is excellent. However, in untreated patients, the disease may present with a wide range of clinical manifestations, most commonly involving the central nervous system, joints, or heart. A small percentage (~10%) of patients may go on to develop a poorly defined fibromyalgia-like illness, post-treatment Lyme disease (PTLD) unresponsive to prolonged antimicrobial therapy. Below we integrate current knowledge regarding the ecologic, epidemiologic, microbiologic, and immunologic facets of Lyme disease into a conceptual framework that sheds light on the disorder that healthcare providers encounter.
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Affiliation(s)
- Justin D. Radolf
- Department of Medicine, UConn Health, Farmington, CT 06030, USA
- Department of Pediatrics, UConn Health, Farmington, CT 06030, USA
- Departments of Genetics and Genome Sciences, UConn Health, Farmington, CT 06030, USA
- Departments of Molecular Biology and Biophysics, UConn Health, Farmington, CT 06030, USA
- Department of Immunology, UConn Health, Farmington, CT 06030, USA
| | - Klemen Strle
- Division of Infectious Diseases, Wadsworth Center, NY Department of Health, Albany NY, 12208, USA
| | - Jacob E. Lemieux
- Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Franc Strle
- Department of Infectious Diseases, University Medical Center Ljubljana, Ljubljana, Slovenia
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20
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Xu J, Koizumi N, Nakamura S. Crawling Motility on the Host Tissue Surfaces Is Associated With the Pathogenicity of the Zoonotic Spirochete Leptospira. Front Microbiol 2020; 11:1886. [PMID: 32849465 PMCID: PMC7419657 DOI: 10.3389/fmicb.2020.01886] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 07/20/2020] [Indexed: 12/13/2022] Open
Abstract
Bacterial motility is crucial for many pathogenic species in the process of invasion and/or dissemination. The spirochete bacteria Leptospira spp. cause symptoms, such as hemorrhage, jaundice, and nephritis, in diverse mammals including humans. Although loss-of-motility attenuate the spirochete's virulence, the mechanism of the motility-dependent pathogenicity is unknown. Here, focusing on that Leptospira spp. swim in liquid and crawl on solid surfaces, we investigated the spirochetal dynamics on the host tissues by infecting cultured kidney cells from various species with pathogenic and non-pathogenic leptospires. We found that, in the case of the pathogenic leptospires, a larger fraction of bacteria attached to the host cells and persistently traveled long distances using the crawling mechanism. Our results associate the kinetics and kinematic features of the spirochetal pathogens with their virulence.
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Affiliation(s)
- Jun Xu
- Department of Animal Microbiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
| | - Nobuo Koizumi
- Department of Bacteriology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Shuichi Nakamura
- Department of Applied Physics, Graduate School of Engineering, Tohoku University, Sendai, Japan
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21
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Lin YP, Tan X, Caine JA, Castellanos M, Chaconas G, Coburn J, Leong JM. Strain-specific joint invasion and colonization by Lyme disease spirochetes is promoted by outer surface protein C. PLoS Pathog 2020; 16:e1008516. [PMID: 32413091 PMCID: PMC7255614 DOI: 10.1371/journal.ppat.1008516] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/28/2020] [Accepted: 04/03/2020] [Indexed: 01/06/2023] Open
Abstract
Lyme disease, caused by Borrelia burgdorferi, B. afzelii and B. garinii, is a chronic, multi-systemic infection and the spectrum of tissues affected can vary with the Lyme disease strain. For example, whereas B. garinii infection is associated with neurologic manifestations, B. burgdorferi infection is associated with arthritis. The basis for tissue tropism is poorly understood, but has been long hypothesized to involve strain-specific interactions with host components in the target tissue. OspC (outer surface protein C) is a highly variable outer surface protein required for infectivity, and sequence differences in OspC are associated with variation in tissue invasiveness, but whether OspC directly influences tropism is unknown. We found that OspC binds to the extracellular matrix (ECM) components fibronectin and/or dermatan sulfate in an OspC variant-dependent manner. Murine infection by isogenic B. burgdorferi strains differing only in their ospC coding region revealed that two OspC variants capable of binding dermatan sulfate promoted colonization of all tissues tested, including joints. However, an isogenic strain producing OspC from B. garinii strain PBr, which binds fibronectin but not dermatan sulfate, colonized the skin, heart and bladder, but not joints. Moreover, a strain producing an OspC altered to recognize neither fibronectin nor dermatan sulfate displayed dramatically reduced levels of tissue colonization that were indistinguishable from a strain entirely deficient in OspC. Finally, intravital microscopy revealed that this OspC mutant, in contrast to a strain producing wild type OspC, was defective in promoting joint invasion by B. burgdorferi in living mice. We conclude that OspC functions as an ECM-binding adhesin that is required for joint invasion, and that variation in OspC sequence contributes to strain-specific differences in tissue tropism displayed among Lyme disease spirochetes. Infection by different Lyme disease bacteria is associated with different manifestations, such as cardiac, neurologic, or, in the case of B. burgdorferi, the major cause of Lyme disease in the U.S., joint disease. The basis for these differences is unknown, but likely involve strain-specific interactions with host components in the target tissue. The sequence of the outer surface lipoprotein OspC varies with the strains, and we found that this variation influences the spectrum of host extracellular matrix components recognized. Infection of mice with strains that are identical except for ospC revealed that OspC variants that differ in binding spectrum promote infection of different tissues. A strain producing OspC invaded and colonized the joint in living animals, but an altered OspC protein incapable of binding tissue components did not. Thus, tissue-binding by OspC is critical for infection and joint invasion, and OspC variation directly influences tissue tropism.
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Affiliation(s)
- Yi-Pin Lin
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
- Division of Infectious Diseases, New York State Department of Health, Wadsworth Center, Albany, New York, United States of America
| | - Xi Tan
- Departments of Biochemistry & Molecular Biology and Microbiology, Immunology & Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Jennifer A. Caine
- Division of Infectious Diseases, and Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Mildred Castellanos
- Departments of Biochemistry & Molecular Biology and Microbiology, Immunology & Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - George Chaconas
- Departments of Biochemistry & Molecular Biology and Microbiology, Immunology & Infectious Diseases, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Jenifer Coburn
- Division of Infectious Diseases, and Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- * E-mail: (JC); (JML)
| | - John M. Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
- * E-mail: (JC); (JML)
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22
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Lin YP, Yu Y, Marcinkiewicz AL, Lederman P, Hart TM, Zhang F, Linhardt RJ. Non-anticoagulant Heparin as a Pre-exposure Prophylaxis Prevents Lyme Disease Infection. ACS Infect Dis 2020; 6:503-514. [PMID: 31961652 DOI: 10.1021/acsinfecdis.9b00425] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Lyme disease (LD) is caused by the spirochete Borrelia burgdorferi sensu lato (Bbsl). After transmission to humans by ticks, Bbsl spreads to multiple organs, leading to arthritis, carditis, and neuroborreliosis. No effective prophylaxis against human LD prior to tick exposure is currently available. Thus, a pre-exposure prophylaxis (PrEP) against LD is needed. The establishment of LD bacteria at diverse sites is dictated partly by the binding of Bbsl to proteoglycans (PGs) and glycosaminoglycans (GAGs) in tissues. The drug heparin is structurally similar to these GAGs and inhibits Bbsl attachment to PGs, GAGs, cells, and tissues, suggesting its potential to prevent LD. However, the anticoagulant activity of heparin often results in hemorrhage, hampering the development of this compound as LD PrEP. We have previously synthesized a non-anticoagulant version of heparin (NACH), which was verified for safety in mice and humans. Here, we showed that NACH blocks Bbsl attachment to PGs, GAGs, and mammalian cells. We also found that treating mice with NACH prior to the exposure of ticks carrying Bbsl followed by continuous administration of this compound prevents tissue colonization by Bbsl. Furthermore, NACH-treated mice develop greater levels of IgG and IgM against Bbsl at early stages of infection, suggesting that the upregulation of antibody immune responses may be one of the mechanisms for NACH-mediated LD prevention. This is one of the first studies examining the ability of a heparin-based compound to prevent LD prior to tick exposure. The information presented might also be extended to prevent other infectious diseases agents.
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Affiliation(s)
- Yi-Pin Lin
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, Albany, New York 12208, United States
- Department of Biomedical Sciences, State University of New York at Albany, 1400 Washington Avenue, Albany, New York 12222, United States
| | - Yanlei Yu
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
| | - Ashley L. Marcinkiewicz
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, Albany, New York 12208, United States
| | - Patricia Lederman
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, Albany, New York 12208, United States
| | - Thomas M. Hart
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, 120 New Scotland Avenue, Albany, New York 12208, United States
- Department of Biological Science, State University of New York at Albany, 1400 Washington Avenue, Albany, New York 12222, United States
| | - Fuming Zhang
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
| | - Robert J. Linhardt
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
- Departments of Biology and Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, United States
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23
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Novel targets and strategies to combat borreliosis. Appl Microbiol Biotechnol 2020; 104:1915-1925. [PMID: 31953560 PMCID: PMC7222997 DOI: 10.1007/s00253-020-10375-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/05/2020] [Accepted: 01/12/2020] [Indexed: 12/12/2022]
Abstract
Lyme borreliosis is a bacterial infection that can be spread to humans by infected ticks and may severely affect many organs and tissues. Nearly four decades have elapsed since the discovery of the disease agent called Borrelia burgdorferi. Although there is a plethora of knowledge on the infectious agent and thousands of scientific publications, an effective way on how to combat and prevent Lyme borreliosis has not been found yet. There is no vaccine for humans available, and only one active vaccine program in clinical development is currently running. A spirited search for possible disease interventions is of high public interest as surveillance data indicates that the number of cases of Lyme borreliosis is steadily increasing in Europe and North America. This review provides a condensed digest of the history of vaccine development up to new promising vaccine candidates and strategies that are targeted against Lyme borreliosis, including elements of the tick vector, the reservoir hosts, and the Borrelia pathogen itself.
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24
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Bamm VV, Ko JT, Mainprize IL, Sanderson VP, Wills MKB. Lyme Disease Frontiers: Reconciling Borrelia Biology and Clinical Conundrums. Pathogens 2019; 8:E299. [PMID: 31888245 PMCID: PMC6963551 DOI: 10.3390/pathogens8040299] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 12/06/2019] [Accepted: 12/12/2019] [Indexed: 12/18/2022] Open
Abstract
Lyme disease is a complex tick-borne zoonosis that poses an escalating public health threat in several parts of the world, despite sophisticated healthcare infrastructure and decades of effort to address the problem. Concepts like the true burden of the illness, from incidence rates to longstanding consequences of infection, and optimal case management, also remain shrouded in controversy. At the heart of this multidisciplinary issue are the causative spirochetal pathogens belonging to the Borrelia Lyme complex. Their unusual physiology and versatile lifestyle have challenged microbiologists, and may also hold the key to unlocking mysteries of the disease. The goal of this review is therefore to integrate established and emerging concepts of Borrelia biology and pathogenesis, and position them in the broader context of biomedical research and clinical practice. We begin by considering the conventions around diagnosing and characterizing Lyme disease that have served as a conceptual framework for the discipline. We then explore virulence from the perspective of both host (genetic and environmental predispositions) and pathogen (serotypes, dissemination, and immune modulation), as well as considering antimicrobial strategies (lab methodology, resistance, persistence, and clinical application), and borrelial adaptations of hypothesized medical significance (phenotypic plasticity or pleomorphy).
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Affiliation(s)
| | | | | | | | - Melanie K. B. Wills
- G. Magnotta Lyme Disease Research Lab, Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada; (V.V.B.); (J.T.K.); (I.L.M.); (V.P.S.)
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25
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Structural determination of the complement inhibitory domain of Borrelia burgdorferi BBK32 provides insight into classical pathway complement evasion by Lyme disease spirochetes. PLoS Pathog 2019; 15:e1007659. [PMID: 30897158 PMCID: PMC6445466 DOI: 10.1371/journal.ppat.1007659] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 04/02/2019] [Accepted: 02/26/2019] [Indexed: 01/07/2023] Open
Abstract
The carboxy-terminal domain of the BBK32 protein from Borrelia burgdorferi sensu stricto, termed BBK32-C, binds and inhibits the initiating serine protease of the human classical complement pathway, C1r. In this study we investigated the function of BBK32 orthologues of the Lyme-associated Borrelia burgdorferi sensu lato complex, designated BAD16 from B. afzelii strain PGau and BGD19 from B. garinii strain IP90. Our data show that B. afzelii BAD16-C exhibits BBK32-C-like activities in all assays tested, including high-affinity binding to purified C1r protease and C1 complex, and potent inhibition of the classical complement pathway. Recombinant B. garinii BGD19-C also bound C1 and C1r with high-affinity yet exhibited significantly reduced in vitro complement inhibitory activities relative to BBK32-C or BAD16-C. Interestingly, natively produced BGD19 weakly recognized C1r relative to BBK32 and BAD16 and, unlike these proteins, BGD19 did not confer significant protection from serum killing. Site-directed mutagenesis was performed to convert BBK32-C to resemble BGD19-C at three residue positions that are identical between BBK32 and BAD16 but different in BGD19. The resulting chimeric protein was designated BXK32-C and this BBK32-C variant mimicked the properties observed for BGD19-C. To query the disparate complement inhibitory activities of BBK32 orthologues, the crystal structure of BBK32-C was solved to 1.7Å limiting resolution. BBK32-C adopts an anti-parallel four-helix bundle fold with a fifth alpha-helix protruding from the helical core. The structure revealed that the three residues targeted in the BXK32-C chimera are surface-exposed, further supporting their potential relevance in C1r binding and inhibition. Additional binding assays showed that BBK32-C only recognized C1r fragments containing the serine protease domain. The structure-function studies reported here improve our understanding of how BBK32 recognizes and inhibits C1r and provide new insight into complement evasion mechanisms of Lyme-associated spirochetes of the B. burgdorferi sensu lato complex.
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Cuellar J, Pietikäinen A, Glader O, Liljenbäck H, Söderström M, Hurme S, Salo J, Hytönen J. Borrelia burgdorferi Infection in Biglycan Knockout Mice. J Infect Dis 2019; 220:116-126. [DOI: 10.1093/infdis/jiz050] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 01/28/2019] [Indexed: 12/25/2022] Open
Affiliation(s)
- Julia Cuellar
- Institute of Biomedicine, University of Turku
- Turku Doctoral Programme of Molecular Medicine, Faculty of Medicine, University of Turku
| | - Annukka Pietikäinen
- Institute of Biomedicine, University of Turku
- Turku Doctoral Programme of Molecular Medicine, Faculty of Medicine, University of Turku
| | - Otto Glader
- Institute of Biomedicine, University of Turku
| | - Heidi Liljenbäck
- Turku Center for Disease Modeling, University of Turku
- Turku PET Centre, University of Turku
| | - Mirva Söderström
- Department of Pathology and Forensic Medicine, University of Turku and Turku University Hospital
| | - Saija Hurme
- Department of Biostatistics, University of Turku
| | | | - Jukka Hytönen
- Institute of Biomedicine, University of Turku
- Laboratory Division, Unit of Clinical Microbiology, Turku University Hospital, Turku, Finland
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27
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Vechtova P, Sterbova J, Sterba J, Vancova M, Rego ROM, Selinger M, Strnad M, Golovchenko M, Rudenko N, Grubhoffer L. A bite so sweet: the glycobiology interface of tick-host-pathogen interactions. Parasit Vectors 2018; 11:594. [PMID: 30428923 PMCID: PMC6236881 DOI: 10.1186/s13071-018-3062-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 08/14/2018] [Indexed: 11/10/2022] Open
Abstract
Vector-borne diseases constitute 17% of all infectious diseases in the world; among the blood-feeding arthropods, ticks transmit the highest number of pathogens. Understanding the interactions between the tick vector, the mammalian host and the pathogens circulating between them is the basis for the successful development of vaccines against ticks or the tick-transmitted pathogens as well as for the development of specific treatments against tick-borne infections. A lot of effort has been put into transcriptomic and proteomic analyses; however, the protein-carbohydrate interactions and the overall glycobiology of ticks and tick-borne pathogens has not been given the importance or priority deserved. Novel (bio)analytical techniques and their availability have immensely increased the possibilities in glycobiology research and thus novel information in the glycobiology of ticks and tick-borne pathogens is being generated at a faster pace each year. This review brings a comprehensive summary of the knowledge on both the glycosylated proteins and the glycan-binding proteins of the ticks as well as the tick-transmitted pathogens, with emphasis on the interactions allowing the infection of both the ticks and the hosts by various bacteria and tick-borne encephalitis virus.
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Affiliation(s)
- Pavlina Vechtova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic. .,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic.
| | - Jarmila Sterbova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Jan Sterba
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Marie Vancova
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Ryan O M Rego
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Martin Selinger
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Martin Strnad
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
| | - Maryna Golovchenko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic
| | - Nataliia Rudenko
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic
| | - Libor Grubhoffer
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-37005, České Budějovice, Czech Republic.,Faculty of Science, University of South Bohemia, Branišovská 1760, CZ-37005, České Budějovice, Czech Republic
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28
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Investigating disease severity in an animal model of concurrent babesiosis and Lyme disease. Int J Parasitol 2018; 49:145-151. [PMID: 30367867 DOI: 10.1016/j.ijpara.2018.06.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/11/2018] [Accepted: 06/19/2018] [Indexed: 02/04/2023]
Abstract
The incidence of babesiosis, Lyme disease and other tick-borne diseases has increased steadily in Europe and North America during the last five decades. Babesia microti is transmitted by species of Ixodes, the same ticks that transmit the Lyme disease-causing spirochete, Borrelia burgdorferi. B. microti can also be transmitted through transfusion of blood products and is the most common transfusion-transmitted infection in the U.S.A. Ixodes ticks are commonly infected with both B. microti and B. burgdorferi, and are competent vectors for transmitting them together into hosts. Few studies have examined the effects of coinfections on humans and they had somewhat contradictory results. One study linked coinfection with B. microti to a greater number of symptoms of overall disease in patients, while another report indicated that B. burgdorferi infection either did not affect babesiosis symptoms or decreased its severity. Mouse models of infection that manifest pathological effects similar to those observed in human babesiosis and Lyme disease offer a unique opportunity to thoroughly investigate the effects of coinfection on the host. Lyme disease has been studied using the susceptible C3H mouse infection model, which can also be used to examine B. microti infection to understand pathological mechanisms of human diseases, both during a single infection and during coinfections. We observed that high B. microti parasitaemia leads to low haemoglobin levels in infected mice, reflecting the anaemia observed in human babesiosis. Similar to humans, B. microti coinfection appears to enhance the severity of Lyme disease-like symptoms in mice. Coinfected mice have lower peak B. microti parasitaemia compared to mice infected with B. microti alone, which may reflect attenuation of babesiosis symptoms reported in some human coinfections. These findings suggest that B. burgdorferi coinfection attenuates parasite growth while B. microti presence exacerbates Lyme disease-like symptoms in mice.
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Cell behavior of the highly sticky bacterium Acinetobacter sp. Tol 5 during adhesion in laminar flows. Sci Rep 2018; 8:8285. [PMID: 29844614 PMCID: PMC5974025 DOI: 10.1038/s41598-018-26699-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/11/2018] [Indexed: 12/17/2022] Open
Abstract
It is important to characterize how medically, industrially, or environmentally important bacteria adhere to surfaces in liquid flows in order to control their cell adhesion and subsequent biofilm formation. Acinetobacter sp. Tol 5 is a remarkably sticky bacterium that autoagglutinates through the adhesive nanofiber protein AtaA, which is applicable to cell immobilization in bioprocesses. In this study, the adhesion and behavior of Tol 5 cells in laminar flows were investigated using flow cell systems. Tol 5 cells autoagglutinated through AtaA and formed cell clumps during flowing. The cell clumps rather than single cells went downward due to gravity and adhered to the bottom surface. Under appropriate shear stress, a twin vortex was caused by a separated flow generated at the rear of the pre-immobilized cell clumps and carried the small cell clumps to this location, resulting in their stacking there. The rearward immobilized cell clumps developed into a large, stable aggregate with a streamlined shape, independent of cell growth. Cell clumps hardly ever developed under weak shear stress that could not generate a twin vortex and were broken up under excessively strong shear stress. These cell behaviors including the importance of clumping are interesting features in the bacterial adhesion processes.
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30
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Pedersen RM, Grønnemose RB, Stærk K, Asferg CA, Andersen TB, Kolmos HJ, Møller-Jensen J, Andersen TE. A Method for Quantification of Epithelium Colonization Capacity by Pathogenic Bacteria. Front Cell Infect Microbiol 2018; 8:16. [PMID: 29450193 PMCID: PMC5799267 DOI: 10.3389/fcimb.2018.00016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 01/12/2018] [Indexed: 11/13/2022] Open
Abstract
Most bacterial infections initiate at the mucosal epithelium lining the gastrointestinal, respiratory, and urogenital tracts. At these sites, bacterial pathogens must adhere and increase in numbers to effectively breach the outer barrier and invade the host. If the bacterium succeeds in reaching the bloodstream, effective dissemination again requires that bacteria in the blood, reestablish contact to distant endothelium sites and form secondary site foci. The infectious potential of bacteria is therefore closely linked to their ability to adhere to, colonize, and invade epithelial and endothelial surfaces. Measurement of bacterial adhesion to epithelial cells is therefore standard procedure in studies of bacterial virulence. Traditionally, such measurements have been conducted with microtiter plate cell cultures to which bacteria are added, followed by washing procedures and final quantification of retained bacteria by agar plating. This approach is fast and straightforward, but yields only a rough estimate of the adhesive properties of the bacteria upon contact, and little information on the ability of the bacterium to colonize these surfaces under relevant physiological conditions. Here, we present a method in which epithelia/endothelia are simulated by flow chamber-grown human cell layers, and infection is induced by seeding of pathogenic bacteria on these surfaces under conditions that simulate the physiological microenvironment. Quantification of bacterial adhesion and colonization of the cell layers is then performed by in situ time-lapse fluorescence microscopy and automatic detection of bacterial surface coverage. The method is demonstrated in three different infection models, simulating Staphylococcus aureus endothelial infection and Escherichia coli intestinal- and uroepithelial infection. The approach yields valuable information on the fitness of the bacterium to successfully adhere to and colonize epithelial surfaces and can be used to evaluate the influence of specific virulence genes, growth conditions, and antimicrobial treatment on this process.
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Affiliation(s)
- Rune M Pedersen
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Rasmus B Grønnemose
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Kristian Stærk
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Cecilie A Asferg
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Thea B Andersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Hans J Kolmos
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
| | - Jakob Møller-Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Thomas E Andersen
- Research Unit of Clinical Microbiology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark
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31
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Lin YP, Li L, Zhang F, Linhardt RJ. Borrelia burgdorferi glycosaminoglycan-binding proteins: a potential target for new therapeutics against Lyme disease. MICROBIOLOGY-SGM 2017; 163:1759-1766. [PMID: 29116038 DOI: 10.1099/mic.0.000571] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The spirochete bacterium Borrelia burgdorferi sensu lato is the causative agent of Lyme disease, the most common vector-borne disease in Europe and the United States. The spirochetes can be transmitted to humans via ticks, and then spread to different tissues, leading to arthritis, carditis and neuroborreliosis. Although antibiotics have commonly been used to treat infected individuals, some treated patients do not respond to antibiotics and experience persistent, long-term arthritis. Thus, there is a need to investigate alternative therapeutics against Lyme disease. The spirochete bacterium colonization is partly attributed to the binding of the bacterial outer-surface proteins to the glycosaminoglycan (GAG) chains of host proteoglycans. Blocking the binding of these proteins to GAGs is a potential strategy to prevent infection. In this review, we have summarized the recent reports of B. burgdorferi sensu lato GAG-binding proteins and discussed the potential use of synthetic and semi-synthetic compounds, including GAG analogues, to block pathogen interaction with GAGs. Such information should motivate the discovery and development of novel GAG analogues as new therapeutics for Lyme disease. New therapeutic approaches should eventually reduce the burden of Lyme disease and improve human health.
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Affiliation(s)
- Yi-Pin Lin
- Department of Biomedical Science, State University of New York at Albany, Albany, NY, USA.,Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Lingyun Li
- Division of Environmental Health Science, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Fuming Zhang
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Robert J Linhardt
- Departments of Biology and Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA.,Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA.,Department of Chemistry and Chemical Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA
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32
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Kumar B, Miller K, Charon NW, Legleiter J. Periplasmic flagella in Borrelia burgdoferi function to maintain cellular integrity upon external stress. PLoS One 2017; 12:e0184648. [PMID: 28898274 PMCID: PMC5595309 DOI: 10.1371/journal.pone.0184648] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 08/28/2017] [Indexed: 12/15/2022] Open
Abstract
Tapping mode atomic force microscopy (AFM) in solution was used to analyze the role of the internally located periplasmic flagella (PFs) of the Lyme disease spirochete Borrelia burgdorferi in withstanding externally applied cellular stresses. By systematically imaging immobilized spirochetes with increasing tapping forces, we found that mutants that lack PFs are more readily compressed and damaged by the imaging process compared to wild-type cells. This finding suggest that the PFs, aside from being essential for motility and involved in cell shape, play a cytoskeletal role in dissipating energy and maintaining cellular integrity in the presence of external stress.
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Affiliation(s)
- Bharath Kumar
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
| | - Kelly Miller
- Department of Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia, United States of America
| | - Nyles W. Charon
- Department of Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia, United States of America
- WVU nanoSAFE, West Virginia University, Morgantown, West Virginia, United States of America
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia, United States of America
- WVU nanoSAFE, West Virginia University, Morgantown, West Virginia, United States of America
- Blanchette Rockefeller Neurosciences Institute, West Virginia University, Morgantown, West Virginia, United States of America
- * E-mail:
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Pietikäinen A, Siitonen R, Liljenbäck H, Eskola O, Söderström M, Roivainen A, Hytönen J. In vivo imaging of Lyme arthritis in mice by [ 18F]fluorodeoxyglucose positron emission tomography/computed tomography. Scand J Rheumatol 2017. [PMID: 28649922 DOI: 10.1080/03009742.2017.1287306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Lyme borreliosis (LB) is a tick-borne infectious disease caused by Borrelia burgdorferi spirochaetes, which are able to disseminate from the tick-bite site to distant organs. Mouse models are widely used to study LB and especially Lyme arthritis (LA), but only a few whole-animal in vivo imaging studies on the pathogenesis of B. burgdorferi infection in mice have been published so far. The existing imaging techniques have their drawbacks and, therefore, novel tools to complement the array of available LB imaging methodologies are needed. METHOD The applicability of positron emission tomography combined with computed tomography (PET/CT) imaging was evaluated as a method to monitor LB and especially LA in the C3H/HeN mouse model infected with wild-type B. burgdorferi N40 bacteria. The imaging results were compared with the traditional LA analysis methods, such as tibiotarsal joint swelling and histopathological assessment of joint inflammation. RESULTS PET/CT imaging provided high-resolution images with quantitative information on the spatial and temporal distribution of the [18F]fluorodeoxyglucose ([18F]FDG) tracer in B. burgdorferi-infected mice. The [18F]FDG accumulated in the affected joints and activated lymph nodes of infected mice, while the tracer signal could not be visualized in these organs in uninfected control animals. Importantly, in vivo PET/CT imaging data were in agreement with the histopathological scoring of inflammation of mouse joints. CONCLUSION PET/CT imaging with [18F]FDG is a reliable method to longitudinally monitor the development and progression of B. burgdorferi infection-induced inflammation in vivo in mouse joints.
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Affiliation(s)
- A Pietikäinen
- a Department of Medical Microbiology and Immunology , University of Turku , Turku , Finland.,b Turku Doctoral Programme for Molecular Medicine , University of Turku , Turku , Finland
| | - R Siitonen
- c Turku PET Centre , Turku University Hospital and University of Turku , Turku , Finland
| | - H Liljenbäck
- c Turku PET Centre , Turku University Hospital and University of Turku , Turku , Finland.,d Turku Center for Disease Modeling , University of Turku , Turku , Finland
| | - O Eskola
- c Turku PET Centre , Turku University Hospital and University of Turku , Turku , Finland
| | - M Söderström
- e Department of Pathology and Forensic Medicine , Turku University Hospital and University of Turku , Turku , Finland
| | - A Roivainen
- c Turku PET Centre , Turku University Hospital and University of Turku , Turku , Finland.,d Turku Center for Disease Modeling , University of Turku , Turku , Finland
| | - J Hytönen
- a Department of Medical Microbiology and Immunology , University of Turku , Turku , Finland.,f Department of Clinical Microbiology and Immunology , Turku University Hospital , Turku , Finland
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Kao WCA, Pětrošová H, Ebady R, Lithgow KV, Rojas P, Zhang Y, Kim YE, Kim YR, Odisho T, Gupta N, Moter A, Cameron CE, Moriarty TJ. Identification of Tp0751 (Pallilysin) as a Treponema pallidum Vascular Adhesin by Heterologous Expression in the Lyme disease Spirochete. Sci Rep 2017; 7:1538. [PMID: 28484210 PMCID: PMC5431505 DOI: 10.1038/s41598-017-01589-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 03/29/2017] [Indexed: 11/25/2022] Open
Abstract
Treponema pallidum subsp. pallidum, the causative agent of syphilis, is a highly invasive spirochete pathogen that uses the vasculature to disseminate throughout the body. Identification of bacterial factors promoting dissemination is crucial for syphilis vaccine development. An important step in dissemination is bacterial adhesion to blood vessel surfaces, a process mediated by bacterial proteins that can withstand forces imposed on adhesive bonds by blood flow (vascular adhesins). The study of T. pallidum vascular adhesins is hindered by the uncultivable nature of this pathogen. We overcame these limitations by expressing T. pallidum adhesin Tp0751 (pallilysin) in an adhesion-attenuated strain of the cultivable spirochete Borrelia burgdorferi. Under fluid shear stress representative of conditions in postcapillary venules, Tp0751 restored bacterial-vascular interactions to levels similar to those observed for infectious B. burgdorferi and a gain-of-function strain expressing B. burgdorferi vascular adhesin BBK32. The strength and stability of Tp0751- and BBK32-dependent endothelial interactions under physiological shear stress were similar, although the mechanisms stabilizing these interactions were distinct. Tp0751 expression also permitted bacteria to interact with postcapillary venules in live mice as effectively as BBK32-expressing strains. These results demonstrate that Tp0751 can function as a vascular adhesin.
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Affiliation(s)
- Wei-Chien Andrew Kao
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Helena Pětrošová
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Rhodaba Ebady
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Karen V Lithgow
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - Pablo Rojas
- Charité University Medicine Berlin, Berlin, Germany
| | - Yang Zhang
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Yae-Eun Kim
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Yae-Ram Kim
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Tanya Odisho
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Nupur Gupta
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada
| | - Annette Moter
- Biofilmcenter, German Heart Center Berlin, Berlin, Germany
| | - Caroline E Cameron
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada.
| | - Tara J Moriarty
- Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada. .,Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
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André A, Mouton A, Millien V, Michaux J. Liver microbiome of Peromyscus leucopus, a key reservoir host species for emerging infectious diseases in North America. INFECTION GENETICS AND EVOLUTION 2017; 52:10-18. [PMID: 28412525 DOI: 10.1016/j.meegid.2017.04.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 03/31/2017] [Accepted: 04/11/2017] [Indexed: 12/21/2022]
Abstract
Microbiome studies generally focus on the gut microbiome, which is composed of a large proportion of commensal bacteria. Here we propose a first analysis of the liver microbiome using next generation sequencing as a tool to detect potentially pathogenic strains. We used Peromyscus leucopus, the main reservoir host species of Lyme disease in eastern North America, as a model and sequenced V5-V6 regions of the 16S gene from 18 populations in southern Quebec (Canada). The Lactobacillus genus was found to dominate the liver microbiome. We also detected a large proportion of individuals infected by Bartonella vinsonii arupensis, a human pathogenic bacteria responsible for endocarditis, as well as Borrelia burgdorferi, the pathogen responsible for Lyme disease in North America. We then compared the microbiomes among two P. leucopus genetic clusters occurring on either side of the St. Lawrence River, and did not detect any effect of the host genotype on their liver microbiome assemblage. Finally, we report, for the first time, the presence of B. burgdorferi in a small mammal host from the northern side of the St. Lawrence River, in support of models that have predicted the northern spread of Lyme disease in Canada.
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Affiliation(s)
- A André
- Conservation Genetics Laboratory, University of Liège, Boulevard du Rectorat 26, 4000 Liège, Belgium; Redpath Museum, McGill University, 859 Sherbrooke West, Montreal, QC H3A OC4, Canada.
| | - A Mouton
- Conservation Genetics Laboratory, University of Liège, Boulevard du Rectorat 26, 4000 Liège, Belgium
| | - V Millien
- Redpath Museum, McGill University, 859 Sherbrooke West, Montreal, QC H3A OC4, Canada
| | - J Michaux
- Conservation Genetics Laboratory, University of Liège, Boulevard du Rectorat 26, 4000 Liège, Belgium; CIRAD, UR AGIRs, F-34398 Montpellier, France
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Plasma fibronectin stabilizes Borrelia burgdorferi-endothelial interactions under vascular shear stress by a catch-bond mechanism. Proc Natl Acad Sci U S A 2017; 114:E3490-E3498. [PMID: 28396443 DOI: 10.1073/pnas.1615007114] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Bacterial dissemination via the cardiovascular system is the most common cause of infection mortality. A key step in dissemination is bacterial interaction with endothelia lining blood vessels, which is physically challenging because of the shear stress generated by blood flow. Association of host cells such as leukocytes and platelets with endothelia under vascular shear stress requires mechanically specialized interaction mechanisms, including force-strengthened catch bonds. However, the biomechanical mechanisms supporting vascular interactions of most bacterial pathogens are undefined. Fibronectin (Fn), a ubiquitous host molecule targeted by many pathogens, promotes vascular interactions of the Lyme disease spirochete Borrelia burgdorferi Here, we investigated how B. burgdorferi exploits Fn to interact with endothelia under physiological shear stress, using recently developed live cell imaging and particle-tracking methods for studying bacterial-endothelial interaction biomechanics. We found that B. burgdorferi does not primarily target insoluble matrix Fn deposited on endothelial surfaces but, instead, recruits and induces polymerization of soluble plasma Fn (pFn), an abundant protein in blood plasma that is normally soluble and nonadhesive. Under physiological shear stress, caps of polymerized pFn at bacterial poles formed part of mechanically loaded adhesion complexes, and pFn strengthened and stabilized interactions by a catch-bond mechanism. These results show that B. burgdorferi can transform a ubiquitous but normally nonadhesive blood constituent to increase the efficiency, strength, and stability of bacterial interactions with vascular surfaces. Similar mechanisms may promote dissemination of other Fn-binding pathogens.
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Hyde JA. Borrelia burgdorferi Keeps Moving and Carries on: A Review of Borrelial Dissemination and Invasion. Front Immunol 2017; 8:114. [PMID: 28270812 PMCID: PMC5318424 DOI: 10.3389/fimmu.2017.00114] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 01/25/2017] [Indexed: 12/21/2022] Open
Abstract
Borrelia burgdorferi is the etiological agent of Lyme disease, a multisystemic, multistage, inflammatory infection resulting in patients experiencing cardiac, neurological, and arthritic complications when not treated with antibiotics shortly after exposure. The spirochetal bacterium transmits through the Ixodes vector colonizing the dermis of a mammalian host prior to hematogenous dissemination and invasion of distal tissues all the while combating the immune response as it traverses through its pathogenic lifecycle. The innate immune response controls the borrelial burden in the dermis, but is unable to clear the infection and thereby prevent progression of disease. Dissemination in the mammalian host requires temporal regulation of virulence determinants to allow for vascular interactions, invasion, and colonization of distal tissues. Virulence determinants and/or adhesins are highly heterogenetic among environmental B. burgdorferi strains with particular genotypes being associated with the ability to disseminate to specific tissues and the severity of disease, but fail to generate cross-protective immunity between borrelial strains. The unique motility of B. burgdorferi rendered by the endoflagella serves a vital function for dissemination and protection from immune recognition. Progress has been made toward understanding the chemotactic regulation coordinating the activity of the two polar localized flagellar motors and their role in borrelial virulence, but this regulation is not yet fully understood. Distinct states of motility allow for dynamic interactions between several B. burgdorferi adhesins and host targets that play roles in transendothelial migration. Transmigration across endothelial and blood-brain barriers allows for the invasion of tissues and elicits localized immune responses. The invasive nature of B. burgdorferi is lacking in proactive mechanisms to modulate disease, such as secretion systems and toxins, but recent work has shown degradation of host extracellular matrices by B. burgdorferi contributes to the invasive capabilities of the pathogen. Additionally, B. burgdorferi may use invasion of eukaryotic cells for immune evasion and protection against environmental stresses. This review provides an overview of B. burgdorferi mechanisms for dissemination and invasion in the mammalian host, which are essential for pathogenesis and the development of persistent infection.
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Affiliation(s)
- Jenny A Hyde
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M Health Science Center , Bryan, TX , USA
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Tracy KE, Baumgarth N. Borrelia burgdorferi Manipulates Innate and Adaptive Immunity to Establish Persistence in Rodent Reservoir Hosts. Front Immunol 2017; 8:116. [PMID: 28265270 PMCID: PMC5316537 DOI: 10.3389/fimmu.2017.00116] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 01/25/2017] [Indexed: 01/17/2023] Open
Abstract
Borrelia burgdorferi sensu lato species complex is capable of establishing persistent infections in a wide variety of species, particularly rodents. Infection is asymptomatic or mild in most reservoir host species, indicating successful co-evolution of the pathogen with its natural hosts. However, infected humans and other incidental hosts can develop Lyme disease, a serious inflammatory syndrome characterized by tissue inflammation of joints, heart, muscles, skin, and CNS. Although B. burgdorferi infection induces both innate and adaptive immune responses, they are ultimately ineffective in clearing the infection from reservoir hosts, leading to bacterial persistence. Here, we review some mechanisms by which B. burgdorferi evades the immune system of the rodent host, focusing in particular on the effects of innate immune mechanisms and recent findings suggesting that T-dependent B cell responses are subverted during infection. A better understanding of the mechanisms causing persistence in rodents may help to increase our understanding of the pathogenesis of Lyme disease and ultimately aid in the development of therapies that support effective clearance of the bacterial infection by the host’s immune system.
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Affiliation(s)
- Karen E Tracy
- Graduate Group in Immunology, University of California Davis, Davis, CA, USA; Center for Comparative Medicine, University of California Davis, Davis, CA, USA
| | - Nicole Baumgarth
- Graduate Group in Immunology, University of California Davis, Davis, CA, USA; Center for Comparative Medicine, University of California Davis, Davis, CA, USA; Department of Pathology, Microbiology and Immunology, University of California Davis, Davis, CA, USA
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Caine JA, Coburn J. Multifunctional and Redundant Roles of Borrelia burgdorferi Outer Surface Proteins in Tissue Adhesion, Colonization, and Complement Evasion. Front Immunol 2016; 7:442. [PMID: 27818662 PMCID: PMC5073149 DOI: 10.3389/fimmu.2016.00442] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 10/07/2016] [Indexed: 12/24/2022] Open
Abstract
Borrelia burgdorferi is the causative agent of Lyme disease in the U.S., with at least 25,000 cases reported to the CDC each year. B. burgdorferi is thought to enter and exit the bloodstream to achieve rapid dissemination to distal tissue sites during infection. Travel through the bloodstream requires evasion of immune surveillance and pathogen clearance in the host, a process at which B. burgdorferi is adept. B. burgdorferi encodes greater than 19 adhesive outer surface proteins many of which have been found to bind to host cells or components of the extracellular matrix. Several others bind to host complement regulatory factors, in vitro. Production of many of these adhesive proteins is tightly regulated by environmental cues, and some have been shown to aid in vascular interactions and tissue colonization, as well as survival in the blood, in vivo. Recent work has described multifaceted and redundant roles of B. burgdorferi outer surface proteins in complement component interactions and tissue targeted adhesion and colonization, distinct from their previously identified in vitro binding capabilities. Recent insights into the multifunctional roles of previously well-characterized outer surface proteins such as BBK32, DbpA, CspA, and OspC have changed the way we think about the surface proteome of these organisms during the tick-mammal life cycle. With the combination of new and old in vivo models and in vitro techniques, the field has identified distinct ligand binding domains on BBK32 and DbpA that afford tissue colonization or blood survival to B. burgdorferi. In this review, we describe the multifunctional and redundant roles of many adhesive outer surface proteins of B. burgdorferi in tissue adhesion, colonization, and bloodstream survival that, together, promote the survival of Borrelia spp. throughout maintenance in their multi-host lifestyle.
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Affiliation(s)
- Jennifer A. Caine
- Division of Infectious Disease, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Jenifer Coburn
- Division of Infectious Disease, Center for Infectious Disease Research, Medical College of Wisconsin, Milwaukee, WI, USA
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