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Zhang X, Mai Z, Gao Y, Zhao X, Zhang Y. Selecting potential biomarkers of plasma proteins in mares with endometritis. Equine Vet J 2024; 56:660-669. [PMID: 38616335 DOI: 10.1111/evj.14092] [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: 12/13/2023] [Accepted: 03/14/2024] [Indexed: 04/16/2024]
Abstract
BACKGROUND Endometritis is a common condition in mares that causes significant economic loss. Lacking obvious clinical signs, the clinical diagnosis of endometritis in mares relies on case-by-case clinical examinations, which can be particularly inefficient in large-scale farms. Therefore, the identification of potential biomarkers can serve as a non-invasive and efficient screening technique for endometritis in mares. OBJECTIVES To compare the blood proteome between fertile mares and mares with endometritis to identify biomarkers potentially associated with the development of endometritis and validate their predictive potential. STUDY DESIGN Observational and experimental study. METHODS Differentially expressed proteins were identified via Data Independent Acquisition (DIA) proteomic profiling in a screening cohort composed of eight healthy mares and eight mares with endometritis. Subsequently, enzyme-linked immunosorbent assay was employed that included a validation cohort of 40 healthy mares and 40 mares with endometritis to verify the accuracy and sensitivity of the identified proteins, thereby establishing a diagnostic threshold. RESULTS In the screening cohort, 12 proteins were significantly differentially expressed between endometritis mares and healthy controls (p < 0.05, outside the 1/1.2 to 1.2-fold). In the validation experiment, all six screened proteins were assessed with area under the curve (AUC) >0.8. MAIN LIMITATIONS The samples displayed certain levels of individual heterogeneity, and the number of samples analysed was limited. Additionally, the identified biomarkers were primarily associated with generalised inflammation, which potentially limited their specificity for endometritis. CONCLUSION Levels of plasma proteins are sensitive indicators of equine endometritis and potential tools for endometritis screening. In plasma, fetuin B, von Willebrand factor, vitamin K-dependent protein C, insulin-like growth factor binding protein 3, interleukin 1 receptor accessory protein, and type II cell cytoskeleton showed great predictive ability, with fetuin B being the best predictor (AUC = 0.93, 95% CI: 0.89-0.98), which performs better when combined with all six detected proteins (AUC = 1, 95% CI: 0.99-1.00).
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Affiliation(s)
- Xijun Zhang
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Gansu Key Laboratory of Animal Generational Physiology and Reproductive Regulation, Lanzhou, China
| | - Zhanhai Mai
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
| | - Yujin Gao
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Gansu Key Laboratory of Animal Generational Physiology and Reproductive Regulation, Lanzhou, China
| | - Xingxu Zhao
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Gansu Key Laboratory of Animal Generational Physiology and Reproductive Regulation, Lanzhou, China
| | - Yong Zhang
- College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China
- Gansu Key Laboratory of Animal Generational Physiology and Reproductive Regulation, Lanzhou, China
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2
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Gaudreau LI, Stewart EJ. Vasculature-on-a-chip technologies as platforms for advanced studies of bacterial infections. BIOMICROFLUIDICS 2024; 18:021503. [PMID: 38560344 PMCID: PMC10977040 DOI: 10.1063/5.0179281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 02/29/2024] [Indexed: 04/04/2024]
Abstract
Bacterial infections frequently occur within or near the vascular network as the vascular network connects organ systems and is essential in delivering and removing blood, essential nutrients, and waste products to and from organs. In turn, the vasculature plays a key role in the host immune response to bacterial infections. Technological advancements in microfluidic device design and development have yielded increasingly sophisticated and physiologically relevant models of the vasculature including vasculature-on-a-chip and organ-on-a-chip models. This review aims to highlight advancements in microfluidic device development that have enabled studies of the vascular response to bacteria and bacterial-derived molecules at or near the vascular interface. In the first section of this review, we discuss the use of parallel plate flow chambers and flow cells in studies of bacterial adhesion to the vasculature. We then highlight microfluidic models of the vasculature that have been utilized to study bacteria and bacterial-derived molecules at or near the vascular interface. Next, we review organ-on-a-chip models inclusive of the vasculature and pathogenic bacteria or bacterial-derived molecules that stimulate an inflammatory response within the model system. Finally, we provide recommendations for future research in advancing the understanding of host-bacteria interactions and responses during infections as well as in developing innovative antimicrobials for preventing and treating bacterial infections that capitalize on technological advancements in microfluidic device design and development.
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Affiliation(s)
- Lily Isabelle Gaudreau
- Chemical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, USA
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3
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Slavetinsky J, Lehmann E, Slavetinsky C, Gritsch L, van Dalen R, Kretschmer D, Bleul L, Wolz C, Weidenmaier C, Peschel A. Wall Teichoic Acid Mediates Staphylococcus aureus Binding to Endothelial Cells via the Scavenger Receptor LOX-1. ACS Infect Dis 2023; 9:2133-2140. [PMID: 37910786 DOI: 10.1021/acsinfecdis.3c00252] [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] [Indexed: 11/03/2023]
Abstract
The success of Staphylococcus aureus as a major cause for endovascular infections depends on effective interactions with blood-vessel walls. We have previously shown that S. aureus uses its wall teichoic acid (WTA), a surface glycopolymer, to attach to endothelial cells. However, the endothelial WTA receptor remained unknown. We show here that the endothelial oxidized low-density lipoprotein receptor 1 (LOX-1) interacts with S. aureus WTA and permits effective binding of S. aureus to human endothelial cells. Purified LOX-1 bound to isolated S. aureus WTA. Ectopic LOX-1 expression led to increased binding of S. aureus wild type but not of a WTA-deficient mutant to a cell line, and LOX-1 blockage prevented S. aureus binding to endothelial cells. Moreover, WTA and LOX-1 expression levels correlated with the efficacy of the S. aureus-endothelial interaction. Thus, LOX-1 is an endothelial ligand for S. aureus, whose blockage may help to prevent or treat severe endovascular infections.
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Affiliation(s)
- Jessica Slavetinsky
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Esther Lehmann
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Christoph Slavetinsky
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
- Pediatric Surgery and Urology, University Children's Hospital Tübingen, Tübingen 72076, Germany
| | - Lisa Gritsch
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Rob van Dalen
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Dorothee Kretschmer
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Lisa Bleul
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Christiane Wolz
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Christopher Weidenmaier
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
| | - Andreas Peschel
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen72076, Germany
- Cluster of Excellence EXC 2124 "Controlling Microbes to Fight Infections", University of Tübingen, Tübingen 72076, Germany
- German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen 72076 , Germany
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Papadogeorgou P, Boutsikou T, Boutsikou M, Pergantou E, Mantzou A, Papassotiriou I, Iliodromiti Z, Sokou R, Bouza E, Politou M, Iacovidou N, Valsami S. A Global Assessment of Coagulation Profile and a Novel Insight into Adamts-13 Implication in Neonatal Sepsis. BIOLOGY 2023; 12:1281. [PMID: 37886991 PMCID: PMC10604288 DOI: 10.3390/biology12101281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/19/2023] [Accepted: 09/21/2023] [Indexed: 10/28/2023]
Abstract
Neonatal sepsis is a life-threatening condition associated with significant morbidity and mortality. Sepsis-induced coagulopathy is a well-recognized entity, signifying the strong cross-talk between inflammation and coagulation. The aim of the present study was to compare the coagulation profile between the acute phase of sepsis and recovery in term and preterm neonates. Additional comparisons to healthy neonates were undertaken. Levels of clotting, anti-clotting factors and ADAMTS-13 (A disintegrin and metalloprotease with thrombospondin type-1 motives), the cleaving protein of von Willebrand factor (VWF), were measured in 16 term and preterm neonates in the acute phase of infection and following recovery, as well as in 18 healthy neonates. Clotting times were prolonged, while levels of particular clotting factors were lower in the acute phase of infection compared to controls and recovery. On the other hand, levels of fibrinogen, factor VIII (FVIII) and VWF were significantly higher in the acute phase in comparison to controls and recovery, while they remained persistently higher in the infection group compared to controls. In regard to the anticlotting mechanism, a clear suppression was observed in septic neonates. ADAMTS-13 levels were significantly lower in the acute phase of infection in comparison to controls and recovery (p = 0.015 and 0.004, respectively), while a trend toward superimposed normalization was demonstrated post infection, as higher ADAMTS-13 levels were measured in recovered neonates compared to controls (p = 0.002). The coagulation profile is considerably deranged in neonatal sepsis. ADAMTS-13 deficiency in septic neonates is a novel finding with promising future implications, as ADAMTS-13 substitution may serve as a useful therapeutic option in neonatal sepsis, prompting further investigation in future studies.
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Affiliation(s)
- Paraskevi Papadogeorgou
- Neonatal Department, Medical School, National and Kapodistrian University of Athens, Aretaieio Hospital, 115 28 Athens, Greece
| | - Theodora Boutsikou
- Neonatal Department, Medical School, National and Kapodistrian University of Athens, Aretaieio Hospital, 115 28 Athens, Greece
| | - Maria Boutsikou
- Neonatal Department, Medical School, National and Kapodistrian University of Athens, Aretaieio Hospital, 115 28 Athens, Greece
| | - Eleni Pergantou
- Haemostasis Unit/Haemophilia Centre, “Aghia Sophia” Children’s Hospital, 115 27 Athens, Greece
| | - Aimilia Mantzou
- First Department of Paediatrics, Medical School, National and Kapodistrian University of Athens, “Aghia Sophia” Children’s Hospital, 115 27 Athens, Greece
| | - Ioannis Papassotiriou
- First Department of Paediatrics, Medical School, National and Kapodistrian University of Athens, “Aghia Sophia” Children’s Hospital, 115 27 Athens, Greece
| | - Zoi Iliodromiti
- Neonatal Department, Medical School, National and Kapodistrian University of Athens, Aretaieio Hospital, 115 28 Athens, Greece
| | - Rozeta Sokou
- Neonatal Department, Medical School, National and Kapodistrian University of Athens, Aretaieio Hospital, 115 28 Athens, Greece
| | - Elena Bouza
- 2nd Neonatal Intensive Care Unit, “Aghia Sophia” Children’s Hospital, 115 27 Athens, Greece
| | - Marianna Politou
- Blood Transfusion Department, Aretaieio Hospital, Medical School, National and Kapodistrian University of Athens, 115 28 Athens, Greece
| | - Nikoletta Iacovidou
- Neonatal Department, Medical School, National and Kapodistrian University of Athens, Aretaieio Hospital, 115 28 Athens, Greece
| | - Serena Valsami
- Blood Transfusion Department, Aretaieio Hospital, Medical School, National and Kapodistrian University of Athens, 115 28 Athens, Greece
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5
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Nappi F, Avtaar Singh SS. Host-Bacterium Interaction Mechanisms in Staphylococcus aureus Endocarditis: A Systematic Review. Int J Mol Sci 2023; 24:11068. [PMID: 37446247 DOI: 10.3390/ijms241311068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/21/2023] [Accepted: 07/02/2023] [Indexed: 07/15/2023] Open
Abstract
Staphylococci sp. are the most commonly associated pathogens in infective endocarditis, especially within high-income nations. This along with the increasing burden of healthcare, aging populations, and the protracted infection courses, contribute to a significant challenge for healthcare systems. A systematic review was conducted using relevant search criteria from PubMed, Ovid's version of MEDLINE, and EMBASE, and data were tabulated from randomized controlled trials (RCT), observational cohort studies, meta-analysis, and basic research articles. The review was registered with the OSF register of systematic reviews and followed the PRISMA reporting guidelines. Thirty-five studies met the inclusion criteria and were included in the final systematic review. The role of Staphylococcus aureus and its interaction with the protective shield and host protection functions was identified and highlighted in several studies. The interaction between infective endocarditis pathogens, vascular endothelium, and blood constituents was also explored, giving rise to the potential use of antiplatelets as preventative and/or curative agents. Several factors allow Staphylococcus aureus infections to proliferate within the host with numerous promoting and perpetuating agents. The complex interaction with the hosts' innate immunity also potentiates its virulence. The goal of this study is to attain a better understanding on the molecular pathways involved in infective endocarditis supported by S. aureus and whether therapeutic avenues for the prevention and treatment of IE can be obtained. The use of antibiotic-treated allogeneic tissues have marked antibacterial action, thereby becoming the ideal substitute in native and prosthetic valvular infections. However, the development of effective vaccines against S. aureus still requires in-depth studies.
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Affiliation(s)
- Francesco Nappi
- Department of Cardiac Surgery, Centre Cardiologique du Nord, 93200 Saint-Denis, France
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6
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Chen X, Hu C, Shu Z, Wang X, Zhao Y, Song W, Chen X, Jin M, Xiu Y, Guo X, Kong X, Jiang Y, Guan J, Gongga L, Wang L, Wang B. Isovanillic acid protects mice against Staphylococcus aureus by targeting vWbp and Coa. Future Microbiol 2023; 18:735-749. [PMID: 37526178 DOI: 10.2217/fmb-2022-0219] [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] [Indexed: 08/02/2023] Open
Abstract
Aim: Our primary objective was to investigate the protective effects and mechanisms of isovanillic acid in mice infected with Staphylococcus aureus Newman. Methods: In vitro coagulation assays were used to validate vWbp and Coa as inhibitory targets of isovanillic acid. The binding mechanism of isovanillic acid to vWbp and Coa was investigated using molecular docking and point mutagenesis. Importantly, a lethal pneumonia mouse model was used to assess the effect of isovanillic acid on survival and pathological injury in mice. Results & Conclusion: Isovanillic acid reduced the virulence of S. aureus by directly binding to inhibit the clotting activity of vWbp and Coa, thereby reducing lung histopathological damage and improving the survival rate in mice with pneumonia.
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Affiliation(s)
- Xiangqian Chen
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Chunjie Hu
- Changchun University of Chinese Medicine, Changchun, 130117, China
- Proctology Department, Affiliated Hospital of Changchun University of Chinese Medicine, Changchun, 130021, China
| | - Zunhua Shu
- Changchun University of Chinese Medicine, Changchun, 130117, China
- The Third Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, 130118, China
| | - Xingye Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Yicheng Zhao
- Changchun University of Chinese Medicine, Changchun, 130117, China
- Center for Pathogen Biology & Infectious Diseases, Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun,130021, China
| | - Wu Song
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xiaoyu Chen
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Mengli Jin
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Yang Xiu
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xuerui Guo
- School of Pharmacy, Jilin University, Changchun, 130021, China
| | - Xiangri Kong
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Yijing Jiang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Jiyu Guan
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Lanzi Gongga
- Tibet University Medical College, Tibet, 850000, China
| | - Li Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Bingmei Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
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Asp ME, Thanh MTH, Dutta S, Comstock JA, Welch RD, Patteson AE. Mechanobiology as a tool for addressing the genotype-to-phenotype problem in microbiology. BIOPHYSICS REVIEWS 2023; 4:021304. [PMID: 38504926 PMCID: PMC10903382 DOI: 10.1063/5.0142121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 04/03/2023] [Indexed: 03/21/2024]
Abstract
The central hypothesis of the genotype-phenotype relationship is that the phenotype of a developing organism (i.e., its set of observable attributes) depends on its genome and the environment. However, as we learn more about the genetics and biochemistry of living systems, our understanding does not fully extend to the complex multiscale nature of how cells move, interact, and organize; this gap in understanding is referred to as the genotype-to-phenotype problem. The physics of soft matter sets the background on which living organisms evolved, and the cell environment is a strong determinant of cell phenotype. This inevitably leads to challenges as the full function of many genes, and the diversity of cellular behaviors cannot be assessed without wide screens of environmental conditions. Cellular mechanobiology is an emerging field that provides methodologies to understand how cells integrate chemical and physical environmental stress and signals, and how they are transduced to control cell function. Biofilm forming bacteria represent an attractive model because they are fast growing, genetically malleable and can display sophisticated self-organizing developmental behaviors similar to those found in higher organisms. Here, we propose mechanobiology as a new area of study in prokaryotic systems and describe its potential for unveiling new links between an organism's genome and phenome.
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Infective Endocarditis in High-Income Countries. Metabolites 2022; 12:metabo12080682. [PMID: 35893249 PMCID: PMC9329978 DOI: 10.3390/metabo12080682] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 01/27/2023] Open
Abstract
Infective endocarditis remains an illness that carries a significant burden to healthcare resources. In recent times, there has been a shift from Streptococcus sp. to Staphylococcus sp. as the primary organism of interest. This has significant consequences, given the virulence of Staphylococcus and its propensity to form a biofilm, rendering non-surgical therapy ineffective. In addition, antibiotic resistance has affected treatment of this organism. The cohorts at most risk for Staphylococcal endocarditis are elderly patients with multiple comorbidities. The innovation of transcatheter technologies alongside other cardiac interventions such as implantable devices has contributed to the increased risk attributable to this cohort. We examined the pathophysiology of infective endocarditis carefully. Inter alia, the determinants of Staphylococcus aureus virulence, interaction with host immunity, as well as the discovery and emergence of a potential vaccine, were investigated. Furthermore, the potential role of prophylactic antibiotics during dental procedures was also evaluated. As rates of transcatheter device implantation increase, endocarditis is expected to increase, especially in this high-risk group. A high level of suspicion is needed alongside early initiation of therapy and referral to the heart team to improve outcomes.
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Xie W, Lorenz M, Poosch F, Palme R, Zechner D, Vollmar B, Grambow E, Strüder D. 3D-printed lightweight dorsal skin fold chambers from PEEK reduce chamber-related animal distress. Sci Rep 2022; 12:11599. [PMID: 35803979 PMCID: PMC9270450 DOI: 10.1038/s41598-022-13924-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 05/30/2022] [Indexed: 11/16/2022] Open
Abstract
The dorsal skinfold chamber is one of the most important in vivo models for repetitive longitudinal assessment of microcirculation and inflammation. This study aimed to refine this model by introducing a new lightweight chamber made from polyetheretherketone (PEEK). Body weight, burrowing activity, distress, faecal corticosterone metabolites and the tilting angle of the chambers were analysed in mice carrying either a standard titanium chamber or a PEEK chamber. Data was obtained before chamber preparation and over a postoperative period of three weeks. In the early postoperative phase, reduced body weight and increased faecal corticosterone metabolites were found in mice with titanium chambers. Chamber tilting and tilting-related complications were reduced in mice with PEEK chambers. The distress score was significantly increased in both groups after chamber preparation, but only returned to preoperative values in mice with PEEK chambers. In summary, we have shown that light chambers reduce animal distress and may extend the maximum dorsal skinfold chamber observation time. Chambers made of PEEK are particularly suitable for this purpose: They are autoclavable, sufficiently stable to withstand rodent bites, inexpensive, and widely available through 3D printing.
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Affiliation(s)
- Wentao Xie
- Institute for Experimental Surgery, Rostock University Medical Center, 18057, Rostock, Germany.,Department of Vascular and Thyroid Surgery, Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China
| | - Matthias Lorenz
- Faculty of Engineering, Technology, Business and Design, University of Applied Sciences, 23966, Wismar, Germany
| | - Friederike Poosch
- Department of Otorhinolaryngology, Head and Neck Surgery "Otto Koerner", Rostock University Medical Center, 18057, Rostock, Germany
| | - Rupert Palme
- Unit of Physiology, Pathophysiology and Experimental Endocrinology, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, 1210, Vienna, Austria
| | - Dietmar Zechner
- Institute for Experimental Surgery, Rostock University Medical Center, 18057, Rostock, Germany
| | - Brigitte Vollmar
- Institute for Experimental Surgery, Rostock University Medical Center, 18057, Rostock, Germany
| | - Eberhard Grambow
- Institute for Experimental Surgery, Rostock University Medical Center, 18057, Rostock, Germany. .,Department of General, Visceral, Thoracic, Vascular and Transplantation Surgery, Rostock University Medical Center, Schillingallee 35, 18057, Rostock, Germany.
| | - Daniel Strüder
- Institute for Experimental Surgery, Rostock University Medical Center, 18057, Rostock, Germany.,Department of Otorhinolaryngology, Head and Neck Surgery "Otto Koerner", Rostock University Medical Center, 18057, Rostock, Germany
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10
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Caldara M, Belgiovine C, Secchi E, Rusconi R. Environmental, Microbiological, and Immunological Features of Bacterial Biofilms Associated with Implanted Medical Devices. Clin Microbiol Rev 2022; 35:e0022120. [PMID: 35044203 PMCID: PMC8768833 DOI: 10.1128/cmr.00221-20] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The spread of biofilms on medical implants represents one of the principal triggers of persistent and chronic infections in clinical settings, and it has been the subject of many studies in the past few years, with most of them focused on prosthetic joint infections. We review here recent works on biofilm formation and microbial colonization on a large variety of indwelling devices, ranging from heart valves and pacemakers to urological and breast implants and from biliary stents and endoscopic tubes to contact lenses and neurosurgical implants. We focus on bacterial abundance and distribution across different devices and body sites and on the role of environmental features, such as the presence of fluid flow and properties of the implant surface, as well as on the interplay between bacterial colonization and the response of the human immune system.
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Affiliation(s)
- Marina Caldara
- Interdepartmental Center on Safety, Technologies, and Agri-food Innovation (SITEIA.PARMA), University of Parma, Parma, Italy
| | - Cristina Belgiovine
- IRCCS Humanitas Research Hospital, Rozzano–Milan, Italy
- Scuola di Specializzazione in Microbiologia e Virologia, Università degli Studi di Pavia, Pavia, Italy
| | - Eleonora Secchi
- Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
| | - Roberto Rusconi
- IRCCS Humanitas Research Hospital, Rozzano–Milan, Italy
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele–Milan, Italy
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11
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Lerche CJ, Schwartz F, Pries-Heje MM, Fosbøl EL, Iversen K, Jensen PØ, Høiby N, Hyldegaard O, Bundgaard H, Moser C. Potential Advances of Adjunctive Hyperbaric Oxygen Therapy in Infective Endocarditis. Front Cell Infect Microbiol 2022; 12:805964. [PMID: 35186793 PMCID: PMC8851036 DOI: 10.3389/fcimb.2022.805964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 01/06/2022] [Indexed: 12/22/2022] Open
Abstract
Patients with infective endocarditis (IE) form a heterogeneous group by age, co-morbidities and severity ranging from stable patients to patients with life-threatening complications with need for intensive care. A large proportion need surgical intervention. In-hospital mortality is 15-20%. The concept of using hyperbaric oxygen therapy (HBOT) in other severe bacterial infections has been used for many decades supported by various preclinical and clinical studies. However, the availability and capacity of HBOT may be limited for clinical practice and we still lack well-designed studies documenting clinical efficacy. In the present review we highlight the potential beneficial aspects of adjunctive HBOT in patients with IE. Based on the pathogenesis and pathophysiological conditions of IE, we here summarize some of the important mechanisms and effects by HBOT in relation to infection and inflammation in general. In details, we elaborate on the aspects and impact of HBOT in relation to the host response, tissue hypoxia, biofilm, antibiotics and pathogens. Two preclinical (animal) studies have shown beneficial effect of HBOT in IE, but so far, no clinical study has evaluated the feasibility of HBOT in IE. New therapeutic options in IE are much needed and adjunctive HBOT might be a therapeutic option in certain IE patients to decrease morbidity and mortality and improve the long-term outcome of this severe disease.
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Affiliation(s)
- Christian Johann Lerche
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Virus and Microbiology Special Diagnostics, Statens Serum Institut, Copenhagen, Denmark
- *Correspondence: Christian Johann Lerche,
| | - Franziska Schwartz
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
| | - Mia Marie Pries-Heje
- Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Emil Loldrup Fosbøl
- Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Kasper Iversen
- Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Herlev, Denmark
- Department of Emergency Medicine, Herlev and Gentofte Hospital, University of Copenhagen, Herlev, Denmark
| | - Peter Østrup Jensen
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Immunology and Microbiology, Costerton Biofilm Center, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Niels Høiby
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Immunology and Microbiology, Costerton Biofilm Center, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ole Hyldegaard
- Department of Anaesthesia, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Henning Bundgaard
- Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Claus Moser
- Department of Clinical Microbiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
- Department of Immunology and Microbiology, Costerton Biofilm Center, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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12
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Alfeo MJ, Pagotto A, Barbieri G, Foster TJ, Vanhoorelbeke K, De Filippis V, Speziale P, Pietrocola G. Staphylococcus aureus iron-regulated surface determinant B (IsdB) protein interacts with von Willebrand factor and promotes adherence to endothelial cells. Sci Rep 2021; 11:22799. [PMID: 34815454 PMCID: PMC8611056 DOI: 10.1038/s41598-021-02065-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/01/2021] [Indexed: 12/27/2022] Open
Abstract
Staphylococcus aureus is the cause of a spectrum of diseases in humans and animals. The molecular basis of this pathogenicity lies in the expression of a variety of virulence factors, including proteins that mediate adherence to the host plasma and extracellular matrix proteins. In this study, we discovered that the iron-regulated surface determinant B (IsdB) protein, besides being involved in iron transport and vitronectin binding, interacts with von Willebrand Factor (vWF). IsdB-expressing bacteria bound to both soluble and immobilized vWF. The binding of recombinant IsdB to vWF was blocked by heparin and reduced at high ionic strength. Furthermore, treatment with ristocetin, an allosteric agent that promotes the exposure of the A1 domain of vWF, potentiates the binding of IsdB to vWF. Both near-iron transporter motifs NEAT1 and NEAT2 of IsdB individually bound recombinant A1 domain with KD values in the micromolar range. The binding of IsdB and adhesion of S. aureus expressing IsdB to monolayers of activated endothelial cells was significantly inhibited by a monoclonal antibody against the A1 domain and by IsdB reactive IgG from patients with staphylococcal endocarditis. This suggests the importance of IsdB in adherence of S. aureus to the endothelium colonization and as potential therapeutic target.
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Affiliation(s)
- Mariangela J Alfeo
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Viale Taramelli 3/b, 27100, Pavia, Italy
| | - Anna Pagotto
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via Marzolo 5, 35131, Padua, Italy
| | - Giulia Barbieri
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - Timothy J Foster
- Microbiology Department, Trinity College Dublin, Dublin, Ireland
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
| | - Vincenzo De Filippis
- Department of Pharmaceutical and Pharmacological Sciences, University of Padua, Via Marzolo 5, 35131, Padua, Italy
| | - Pietro Speziale
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Viale Taramelli 3/b, 27100, Pavia, Italy
| | - Giampiero Pietrocola
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Viale Taramelli 3/b, 27100, Pavia, Italy.
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13
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Barnes AMT, Frank KL, Dunny GM. Enterococcal Endocarditis: Hiding in Plain Sight. Front Cell Infect Microbiol 2021; 11:722482. [PMID: 34527603 PMCID: PMC8435889 DOI: 10.3389/fcimb.2021.722482] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/09/2021] [Indexed: 12/12/2022] Open
Abstract
Enterococcus faecalis is a major opportunistic bacterial pathogen of increasing clinical relevance. A substantial body of experimental evidence suggests that early biofilm formation plays a critical role in these infections, as well as in colonization and persistence in the GI tract as a commensal member of the microbiome in most terrestrial animals. Animal models of experimental endocarditis generally involve inducing mechanical valve damage by cardiac catheterization prior to infection, and it has long been presumed that endocarditis vegetation formation resulting from bacterial attachment to the endocardial endothelium requires some pre-existing tissue damage. Here we review both historical and contemporary animal model studies demonstrating the robust ability of E. faecalis to directly attach and form stable microcolony biofilms encased within a bacterially-derived extracellular matrix on the undamaged endovascular endothelial surface. We also discuss the morphological similarities when these biofilms form on other host tissues, including when E. faecalis colonizes the GI epithelium as a commensal member of the normal vertebrate microbiome - hiding in plain sight where it can serve as a source for systemic infection via translocation. We propose that these phenotypes may allow the organism to persist as an undetected infection in asymptomatic individuals and thus provide an infectious reservoir for later clinical endocarditis.
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Affiliation(s)
- Aaron M. T. Barnes
- Department of Microbiology and Immunology, University of Minnesota School of Medicine, Minneapolis, MN, United States
- Department of Laboratory Medicine and Pathology, University of Minnesota School of Medicine, Minneapolis, MN, United States
| | - Kristi L. Frank
- Department of Microbiology and Immunology, University of Minnesota School of Medicine, Minneapolis, MN, United States
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Gary M. Dunny
- Department of Microbiology and Immunology, University of Minnesota School of Medicine, Minneapolis, MN, United States
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14
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Lerche CJ, Schwartz F, Theut M, Fosbøl EL, Iversen K, Bundgaard H, Høiby N, Moser C. Anti-biofilm Approach in Infective Endocarditis Exposes New Treatment Strategies for Improved Outcome. Front Cell Dev Biol 2021; 9:643335. [PMID: 34222225 PMCID: PMC8249808 DOI: 10.3389/fcell.2021.643335] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 05/04/2021] [Indexed: 12/13/2022] Open
Abstract
Infective endocarditis (IE) is a life-threatening infective disease with increasing incidence worldwide. From early on, in the antibiotic era, it was recognized that high-dose and long-term antibiotic therapy was correlated to improved outcome. In addition, for several of the common microbial IE etiologies, the use of combination antibiotic therapy further improves outcome. IE vegetations on affected heart valves from patients and experimental animal models resemble biofilm infections. Besides the recalcitrant nature of IE, the microorganisms often present in an aggregated form, and gradients of bacterial activity in the vegetations can be observed. Even after appropriate antibiotic therapy, such microbial formations can often be identified in surgically removed, infected heart valves. Therefore, persistent or recurrent cases of IE, after apparent initial infection control, can be related to biofilm formation in the heart valve vegetations. On this background, the present review will describe potentially novel non-antibiotic, antimicrobial approaches in IE, with special focus on anti-thrombotic strategies and hyperbaric oxygen therapy targeting the biofilm formation of the infected heart valves caused by Staphylococcus aureus. The format is translational from preclinical models to actual clinical treatment strategies.
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Affiliation(s)
- Christian Johann Lerche
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Franziska Schwartz
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Marie Theut
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Emil Loldrup Fosbøl
- Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Kasper Iversen
- Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen, Herlev, Denmark.,Department of Emergency Medicine, Herlev and Gentofte Hospital, University of Copenhagen, Herlev, Denmark
| | - Henning Bundgaard
- Department of Cardiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Niels Høiby
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.,Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Claus Moser
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
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15
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Staphylococcus aureus vWF-binding protein triggers a strong interaction between clumping factor A and host vWF. Commun Biol 2021; 4:453. [PMID: 33846500 PMCID: PMC8041789 DOI: 10.1038/s42003-021-01986-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 03/15/2021] [Indexed: 12/13/2022] Open
Abstract
The Staphylococcus aureus cell wall-anchored adhesin ClfA binds to the very large blood circulating protein, von Willebrand factor (vWF) via vWF-binding protein (vWbp), a secreted protein that does not bind the cell wall covalently. Here we perform force spectroscopy studies on living bacteria to unravel the molecular mechanism of this interaction. We discover that the presence of all three binding partners leads to very high binding forces (2000 pN), largely outperforming other known ternary complexes involving adhesins. Strikingly, our experiments indicate that a direct interaction involving features of the dock, lock and latch mechanism must occur between ClfA and vWF to sustain the extreme tensile strength of the ternary complex. Our results support a previously undescribed mechanism whereby vWbp activates a direct, ultra-strong interaction between ClfA and vWF. This intriguing interaction represents a potential target for therapeutic interventions, including synthetic peptides inhibiting the ultra-strong interactions between ClfA and its ligands. Through force spectroscopy studies on living bacteria, Viljoen et al. characterise the binding of S. aureus to host von Willebrand factor (vWF). They propose that S. aureus vWF-binding protein triggers an ultra-strong interaction between the adhesin clumping factor A and vWF.
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16
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Kisiela DI, Magala P, Interlandi G, Carlucci LA, Ramos A, Tchesnokova V, Basanta B, Yarov-Yarovoy V, Avagyan H, Hovhannisyan A, Thomas WE, Stenkamp RE, Klevit RE, Sokurenko EV. Toggle switch residues control allosteric transitions in bacterial adhesins by participating in a concerted repacking of the protein core. PLoS Pathog 2021; 17:e1009440. [PMID: 33826682 PMCID: PMC8064603 DOI: 10.1371/journal.ppat.1009440] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 04/23/2021] [Accepted: 03/02/2021] [Indexed: 11/18/2022] Open
Abstract
Critical molecular events that control conformational transitions in most allosteric proteins are ill-defined. The mannose-specific FimH protein of Escherichia coli is a prototypic bacterial adhesin that switches from an 'inactive' low-affinity state (LAS) to an 'active' high-affinity state (HAS) conformation allosterically upon mannose binding and mediates shear-dependent catch bond adhesion. Here we identify a novel type of antibody that acts as a kinetic trap and prevents the transition between conformations in both directions. Disruption of the allosteric transitions significantly slows FimH's ability to associate with mannose and blocks bacterial adhesion under dynamic conditions. FimH residues critical for antibody binding form a compact epitope that is located away from the mannose-binding pocket and is structurally conserved in both states. A larger antibody-FimH contact area is identified by NMR and contains residues Leu-34 and Val-35 that move between core-buried and surface-exposed orientations in opposing directions during the transition. Replacement of Leu-34 with a charged glutamic acid stabilizes FimH in the LAS conformation and replacement of Val-35 with glutamic acid traps FimH in the HAS conformation. The antibody is unable to trap the conformations if Leu-34 and Val-35 are replaced with a less bulky alanine. We propose that these residues act as molecular toggle switches and that the bound antibody imposes a steric block to their reorientation in either direction, thereby restricting concerted repacking of side chains that must occur to enable the conformational transition. Residues homologous to the FimH toggle switches are highly conserved across a diverse family of fimbrial adhesins. Replacement of predicted switch residues reveals that another E. coli adhesin, galactose-specific FmlH, is allosteric and can shift from an inactive to an active state. Our study shows that allosteric transitions in bacterial adhesins depend on toggle switch residues and that an antibody that blocks the switch effectively disables adhesive protein function.
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Affiliation(s)
- Dagmara I. Kisiela
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Pearl Magala
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Gianluca Interlandi
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Laura A. Carlucci
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Angelo Ramos
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Veronika Tchesnokova
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Benjamin Basanta
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
- Institute for Protein Design, University of Washington, Seattle, Washington, United States of America
| | - Vladimir Yarov-Yarovoy
- Department of Physiology and Membrane Biology, University of California, Davis, California, United States of America
| | - Hovhannes Avagyan
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Anahit Hovhannisyan
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
| | - Wendy E. Thomas
- Department of Bioengineering, University of Washington, Seattle, Washington, United States of America
| | - Ronald E. Stenkamp
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
- Department of Biological Structure, University of Washington, Seattle, Washington, United States of America
| | - Rachel E. Klevit
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Evgeni V. Sokurenko
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
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17
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Human blood plasma factors affect the adhesion kinetics of Staphylococcus aureus to central venous catheters. Sci Rep 2020; 10:20992. [PMID: 33268809 PMCID: PMC7710740 DOI: 10.1038/s41598-020-77168-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 10/27/2020] [Indexed: 01/03/2023] Open
Abstract
Staphylococcus aureus is a common cause of catheter-related blood stream infections (CRBSI). The bacterium has the ability to form multilayered biofilms on implanted material, which usually requires the removal of the implanted medical device. A first major step of this biofilm formation is the initial adhesion of the bacterium to the artificial surface. Here, we used single-cell force spectroscopy (SCFS) to study the initial adhesion of S. aureus to central venous catheters (CVCs). SCFS performed with S. aureus on the surfaces of naïve CVCs produced comparable maximum adhesion forces on three types of CVCs in the low nN range (~ 2–7 nN). These values were drastically reduced, when CVC surfaces were preincubated with human blood plasma or human serum albumin, and similar reductions were observed when S. aureus cells were probed with freshly explanted CVCs withdrawn from patients without CRBSI. These findings indicate that the initial adhesion capacity of S. aureus to CVC tubing is markedly reduced, once the CVC is inserted into the vein, and that the risk of contamination of the CVC tubing by S. aureus during the insertion process might be reduced by a preconditioning of the CVC surface with blood plasma or serum albumin.
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18
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John A, Günes C, Bolenz C, Vidal-Y-Sy S, Bauer AT, Schneider SW, Gorzelanny C. Bladder cancer-derived interleukin-1 converts the vascular endothelium into a pro-inflammatory and pro-coagulatory surface. BMC Cancer 2020; 20:1178. [PMID: 33267794 PMCID: PMC7709388 DOI: 10.1186/s12885-020-07548-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 10/21/2020] [Indexed: 12/31/2022] Open
Abstract
Background Bladder cancer cells orchestrate tumour progression by pro-inflammatory cytokines. Cytokines modulate the local tumour microenvironment and increase the susceptibility of tumour distant tissues for metastasis. Here, we investigated the impact of human bladder cancer cell derived factors on the ability to modulate and activate human vascular endothelial cells. Methods The pro-inflammatory and pro-coagulatory potential of four different bladder cancer cell lines was accessed by qRT-PCR arrays and ELISA. Modulation and activation of endothelial cells was studied in microfluidic devices. Clinical relevance of our findings was confirmed by immune histology in tissue samples of bladder cancer patients and public transcriptome data. Results The unbalanced ratio between interleukin (IL)-1 and IL-1 receptor antagonist (IL-1ra) in the secretome of bladder cancer cells converted the quiescent vascular endothelium into a pro-adhesive, pro-inflammatory, and pro-coagulatory surface. Microfluidic experiments showed that tumour cell induced endothelial cell activation promoted leukocyte recruitment and platelet adhesion. Human bladder cancer tissue analysis confirmed that loss of IL-1ra and elevated IL-1 expression was associated with enhanced cancer progression. Conclusions Our data indicate that IL-1 and IL-1ra were dysregulated in bladder cancer and could facilitate tumour dissemination through endothelial cell activation. Targeting the IL-1/IL-1ra axis might attenuate tumour-mediated inflammation and metastasis formation. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-020-07548-z.
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Affiliation(s)
- A John
- Department of Urology, University of Ulm, Ulm, Germany
| | - C Günes
- Department of Urology, University of Ulm, Ulm, Germany
| | - C Bolenz
- Department of Urology, University of Ulm, Ulm, Germany
| | - S Vidal-Y-Sy
- Department of Dermatology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - A T Bauer
- Department of Dermatology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - S W Schneider
- Department of Dermatology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - C Gorzelanny
- Department of Dermatology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
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19
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Ferraro F, Patella F, Costa JR, Ketteler R, Kriston‐Vizi J, Cutler DF. Modulation of endothelial organelle size as an antithrombotic strategy. J Thromb Haemost 2020; 18:3296-3308. [PMID: 32881285 PMCID: PMC8436738 DOI: 10.1111/jth.15084] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/31/2020] [Accepted: 08/24/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND It is long established that von Willebrand factor (VWF) is central to hemostasis and thrombosis. Endothelial VWF is stored in cell-specific secretory granules, Weibel-Palade bodies (WPBs), organelles generated in a wide range of lengths (0.5-5.0 µm). WPB size responds to physiological cues and pharmacological treatment, and VWF secretion from shortened WPBs dramatically reduces platelet and plasma VWF adhesion to an endothelial surface. OBJECTIVE We hypothesized that WPB-shortening represented a novel target for antithrombotic therapy. Our objective was to determine whether compounds exhibiting this activity do exist. METHODS Using a microscopy approach coupled to automated image analysis, we measured the size of WPB bodies in primary human endothelial cells treated with licensed compounds for 24 hours. RESULTS AND CONCLUSIONS A novel approach to identification of antithrombotic compounds generated a significant number of candidates with the ability to shorten WPBs. In vitro assays of two selected compounds confirm that they inhibit the pro-hemostatic activity of secreted VWF. This set of compounds acting at a very early stage of the hemostatic process could well prove to be a useful adjunct to current antithrombotic therapeutics. Further, in the current SARS-CoV-2 pandemic, with a considerable fraction of critically ill COVID-19 patients affected by hypercoagulability, these WPB size-reducing drugs might also provide welcome therapeutic leads for frontline clinicians and researchers.
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Affiliation(s)
- Francesco Ferraro
- Endothelial Cell Biology Group, MRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
- Present address:
Department of Biology and Evolution of Marine Organisms (BEOM)Stazione Zoologica Anton DohrnVilla ComunaleNaplesItaly
| | - Francesca Patella
- Endothelial Cell Biology Group, MRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
| | - Joana R. Costa
- Cell Signalling and Autophagy GroupMRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
- Present address:
Leukaemia Biology Research GroupDepartment of Haematology, Cancer InstituteUniversity College LondonLondonUK
| | - Robin Ketteler
- Cell Signalling and Autophagy GroupMRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
| | - Janos Kriston‐Vizi
- Bioinformatics Image Core (BIONIC)MRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
| | - Daniel F. Cutler
- Endothelial Cell Biology Group, MRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
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20
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Na M, Hu Z, Mohammad M, Stroparo MDN, Ali A, Fei Y, Jarneborn A, Verhamme P, Schneewind O, Missiakas D, Jin T. The Expression of von Willebrand Factor-Binding Protein Determines Joint-Invading Capacity of Staphylococcus aureus, a Core Mechanism of Septic Arthritis. mBio 2020; 11:e02472-20. [PMID: 33203754 PMCID: PMC7683397 DOI: 10.1128/mbio.02472-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/14/2020] [Indexed: 12/20/2022] Open
Abstract
Septic arthritis, one of the most dangerous joint diseases, is predominantly caused by Staphylococcus aureus In contrast, coagulase-negative staphylococci are rarely found in septic arthritis. We hypothesize that coagulases released by S. aureus, including coagulase (Coa) and von Willebrand factor-binding protein (vWbp), play potent roles in the induction of septic arthritis. Four isogenic S. aureus strains differing in expression of coagulases (wild-type [WT] Newman, Δcoa, Δvwb, and Δcoa Δvwb) were used to induce septic arthritis in both wild-type and von Willebrand factor (vWF)-deficient mice. Septic arthritis severity was greatly reduced when wild-type mice were infected with the Δcoa Δvwb and Δvwb variants compared to WT or Δcoa strains, suggesting that vWbp rather than Coa is a major virulence factor in S. aureus septic arthritis. vWF-deficient mice were more susceptible to bone damage in septic arthritis, especially when the Δvwb strain was used. Importantly, no difference in arthritis severity between the Δvwb and WT strains was observed in vWF-deficient mice. Collectively, we conclude that vWbp production by S. aureus enhances staphylococcal septic arthritis.IMPORTANCE Septic arthritis remains one of the most dangerous joint diseases with a rapidly progressive disease character. Despite advances in the use of antibiotics, permanent reductions in joint function due to joint deformation and deleterious contractures occur in up to 50% of patients with septic arthritis. So far, it is still largely unknown how S. aureus initiates and establishes joint infection. Here, we demonstrate that von Willebrand factor-binding protein expressed by S. aureus facilitates the initiation of septic arthritis. Such effect might be mediated through its interaction with a host factor (von Willebrand factor). Our finding contributes significantly to the full understanding of septic arthritis etiology and will pave the way for new therapeutic modalities for this devastating disease.
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Affiliation(s)
- Manli Na
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Zhicheng Hu
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- Department of Microbiology and Immunology, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Majd Mohammad
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Mariana do Nascimento Stroparo
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Abukar Ali
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Ying Fei
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- Department of Microbiology and Immunology, The Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Anders Jarneborn
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- Department of Rheumatology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Peter Verhamme
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Olaf Schneewind
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
| | | | - Tao Jin
- Department of Rheumatology and Inflammation Research, Institution of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- Department of Rheumatology, Sahlgrenska University Hospital, Gothenburg, Sweden
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21
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Gomand F, Mitchell WH, Burgain J, Petit J, Borges F, Spagnolie SE, Gaiani C. Shaving and breaking bacterial chains with a viscous flow. SOFT MATTER 2020; 16:9273-9291. [PMID: 32930313 DOI: 10.1039/d0sm00292e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Some food and ferment manufacturing steps such as spray-drying result in the application of viscous stresses to bacteria. This study explores how a viscous flow impacts both bacterial adhesion functionality and bacterial cell organization using a combined experimental and modeling approach. As a model organism we study Lactobacillus rhamnosus GG (LGG) "wild type" (WT), known to feature strong adhesive affinities towards beta-lactoglobulin thanks to pili produced by the bacteria on cell surfaces, along with three cell-surface mutant strains. Applying repeated flows with high shear-rates reduces bacterial adhesive abilities up to 20% for LGG WT. Bacterial chains are also broken by this process, into 2-cell chains at low industrial shear rates, and into single cells at very high shear rates. To rationalize the experimental observations we study numerically and analytically the Stokes equations describing viscous fluid flow around a chain of elastically connected spheroidal cell bodies. In this model setting we examine qualitatively the relationship between surface traction (force per unit area), a proxy for pili removal rate, and bacterial chain length (number of cells). Longer chains result in higher maximal surface tractions, particularly at the chain extremities, while inner cells enjoy a small protection from surface tractions due to hydrodynamic interactions with their neighbors. Chain rupture therefore may act as a mechanism to preserve surface adhesive functionality in bacteria.
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Affiliation(s)
- Faustine Gomand
- LIBio - Université de Lorraine, 2 avenue de la Forêt de Haye, 54500 Vandoeuvre-lès-Nancy, France. and Department of Mathematics, University of Wisconsin-Madison, 480 Lincoln Dr., Madison, WI 53706, USA.
| | - William H Mitchell
- Department of Mathematics, Statistics, and Computer Science, Macalester College, 1600 Grand Ave, St. Paul, MN 55105, USA.
| | - Jennifer Burgain
- LIBio - Université de Lorraine, 2 avenue de la Forêt de Haye, 54500 Vandoeuvre-lès-Nancy, France.
| | - Jérémy Petit
- LIBio - Université de Lorraine, 2 avenue de la Forêt de Haye, 54500 Vandoeuvre-lès-Nancy, France.
| | - Frédéric Borges
- LIBio - Université de Lorraine, 2 avenue de la Forêt de Haye, 54500 Vandoeuvre-lès-Nancy, France.
| | - Saverio E Spagnolie
- Department of Mathematics, University of Wisconsin-Madison, 480 Lincoln Dr., Madison, WI 53706, USA.
| | - Claire Gaiani
- LIBio - Université de Lorraine, 2 avenue de la Forêt de Haye, 54500 Vandoeuvre-lès-Nancy, France.
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Schneider MF, Fallah MA, Mess C, Obser T, Schneppenheim R, Alexander-Katz A, Schneider SW, Huck V. Platelet adhesion and aggregate formation controlled by immobilised and soluble VWF. BMC Mol Cell Biol 2020; 21:64. [PMID: 32917131 PMCID: PMC7488753 DOI: 10.1186/s12860-020-00309-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Accepted: 08/26/2020] [Indexed: 11/21/2022] Open
Abstract
Background It has been demonstrated that von Willebrand factor (VWF) mediated platelet-endothelium and platelet-platelet interactions are shear dependent. The VWF’s mobility under dynamic conditions (e.g. flow) is pivotal to platelet adhesion and VWF-mediated aggregate formation in the cascade of VWF-platelet interactions in haemostasis. Results Combining microfluidic tools with fluorescence and reflection interference contrast microscopy (RICM), here we show, that specific deletions in the A-domains of the biopolymer VWF affect both, adhesion and aggregation properties independently. Intuitively, the deletion of the A1-domain led to a significant decrease in both adhesion and aggregate formation of platelets. Nevertheless, the deletion of the A2-domain revealed a completely different picture, with a significant increase in formation of rolling aggregates (gain of function). We predict that the A2-domain effectively ‘masks’ the potential between the platelet glycoprotein (GP) Ib and the VWF A1-domain. Furthermore, the deletion of the A3-domain led to no significant variation in either of the two functional characteristics. Conclusions These data demonstrate that the macroscopic functional properties i.e. adhesion and aggregate formation cannot simply be assigned to the properties of one particular domain, but have to be explained by cooperative phenomena. The absence or presence of molecular entities likewise affects the properties (thermodynamic phenomenology) of its neighbours, therefore altering the macromolecular function.
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Affiliation(s)
- Matthias F Schneider
- Department of Physics, Medical and Biological Physics, Technical University Dortmund, Emil-Figge-Str. 50, 44227, Dortmund, Germany
| | - Mohammad A Fallah
- Department of Chemistry, University of Konstanz, Universitätsstr. 10, 78457, Constance, Germany
| | - Christian Mess
- University Medical Centre Hamburg-Eppendorf, Centre for Internal Medicine, Martinistr. 52, 20246, Hamburg, Germany
| | - Tobias Obser
- Department of Paediatric Haematology and Oncology, University Medical Centre Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Reinhard Schneppenheim
- Department of Paediatric Haematology and Oncology, University Medical Centre Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Alfredo Alexander-Katz
- Department of Materials Science and Engineerin, Massachusetts Institute of Technology, 400 Technology Sq. (NE46-605), Cambridge, MA, 02139, USA
| | - Stefan W Schneider
- University Medical Centre Hamburg-Eppendorf, Centre for Internal Medicine, Martinistr. 52, 20246, Hamburg, Germany
| | - Volker Huck
- University Medical Centre Hamburg-Eppendorf, Centre for Internal Medicine, Martinistr. 52, 20246, Hamburg, Germany. .,Heidelberg University, Medical Faculty Mannheim, Experimental Dermatology, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
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23
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Steinert M, Ramming I, Bergmann S. Impact of Von Willebrand Factor on Bacterial Pathogenesis. Front Med (Lausanne) 2020; 7:543. [PMID: 33015097 PMCID: PMC7494747 DOI: 10.3389/fmed.2020.00543] [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: 05/28/2020] [Accepted: 07/30/2020] [Indexed: 12/31/2022] Open
Abstract
Von Willebrand factor (VWF) is a mechano-sensitive protein with crucial functions in normal hemostasis, which are strongly dependant on the shear-stress mediated defolding and multimerization of VWF in the blood stream. Apart from bleeding disorders, higher plasma levels of VWF are often associated with a higher risk of cardiovascular diseases. Herein, the disease symptoms are attributed to the inflammatory response of the activated endothelium and share high similarities to the reaction of the host vasculature to systemic infections caused by pathogenic bacteria such as Staphylococcus aureus and Streptococcus pneumoniae. The bacteria recruit circulating VWF, and by binding to immobilized VWF on activated endothelial cells in blood flow, they interfere with the physiological functions of VWF, including platelet recruitment and coagulation. Several bacterial VWF binding proteins have been identified and further characterized by biochemical analyses. Moreover, the development of a combination of sophisticated cell culture systems simulating shear stress levels of the blood flow with microscopic visualization also provided valuable insights into the interaction mechanism between bacteria and VWF-strings. In vivo studies using mouse models of bacterial infection and zebrafish larvae provided evidence that the interaction between bacteria and VWF promotes bacterial attachment, coagulation, and thrombus formation, and thereby contributes to the pathophysiology of severe infectious diseases such as infective endocarditis and bacterial sepsis. This mini-review summarizes the current knowledge of the interaction between bacteria and the mechano-responsive VWF, and corresponding pathophysiological disease symptoms.
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Affiliation(s)
- Michael Steinert
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany.,Department of Infection Biology, Helmholtz Center for Infection Diseases, Braunschweig, Germany
| | - Isabell Ramming
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Simone Bergmann
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany
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25
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Schwarz C, Hoerr V, Töre Y, Hösker V, Hansen U, Van de Vyver H, Niemann S, Kuhlmann MT, Jeibmann A, Wildgruber M, Faber C. Isolating Crucial Steps in Induction of Infective Endocarditis With Preclinical Modeling of Host Pathogen Interaction. Front Microbiol 2020; 11:1325. [PMID: 32625192 PMCID: PMC7314968 DOI: 10.3389/fmicb.2020.01325] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 05/25/2020] [Indexed: 02/06/2023] Open
Abstract
Animal models of Staphylococcus aureus infective endocarditis (IE), especially in rodents, are commonly used to investigate the underlying pathogenesis, disease progression, potential diagnostic approaches, and therapeutic treatment. All these models are based on surgical interventions, and imply valve trauma by placing a polyurethane catheter at the aortic root. While the influence of endothelial damage and inflammation on the induction of IE has been studied intensively, the role of the catheter, as permanent source of bacteremia, and the interplay with bacterial virulence factors during the formation of IE is poorly understood. In our study, we aimed at identifying which set of preconditions is required for induction and formation of IE: (1) tissue injury, (2) permanent presence of bacteria, and (3) presence of the full bacterial repertoire of adhesion proteins. We investigated the manifestation of the disease in different modifications of the animal model, considering different degrees of endothelial damage and the presence or absence of the catheter. In four infection models the induction of IE was assessed by using two bacterial strains with different expression patterns of virulence factors – S. aureus 6850 and Newman. In vivo magnetic resonance imaging showed conspicuous morphological structures on the aortic valves, when an endothelial damage and a continuous bacterial source were present simultaneously. Cellular and inflammatory pathophysiology were characterized additionally by histology, real-time quantitative polymerase chain reaction analysis, and bacterial counts, revealing strain-specific pathogenesis and manifestation of IE, crucially influenced by bacterial adherence and toxicity. The severity of IE was dependent on the degree of endothelial irritation. However, even severe endothelial damage in the absence of a permanent bacterial source resulted in reduced valve infection. The spread of bacteria to other organs was also dependent on the pathogenic profile of the infectious agent.
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Affiliation(s)
- Christian Schwarz
- Translational Research Imaging Center, Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | - Verena Hoerr
- Translational Research Imaging Center, Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany.,Institute of Medical Microbiology, University Hospital Jena, Jena, Germany
| | - Yasemin Töre
- Translational Research Imaging Center, Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | - Vanessa Hösker
- Translational Research Imaging Center, Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
| | - Uwe Hansen
- Institute of Musculoskeletal Medicine, University Hospital Muenster, Muenster, Germany
| | - Hélène Van de Vyver
- Institute of Medical Microbiology, University Hospital Muenster, Muenster, Germany
| | - Silke Niemann
- Institute of Medical Microbiology, University Hospital Muenster, Muenster, Germany
| | - Michael T Kuhlmann
- European Institute for Molecular Imaging, University of Muenster, Muenster, Germany
| | - Astrid Jeibmann
- Institute for Neuropathology, University Hospital Muenster, Muenster, Germany
| | - Moritz Wildgruber
- Translational Research Imaging Center, Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany.,Klinik und Poliklinik für Radiologie, Klinikum der Universität München, Munich, Germany
| | - Cornelius Faber
- Translational Research Imaging Center, Department of Clinical Radiology, University Hospital Muenster, Muenster, Germany
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Liesenborghs L, Meyers S, Vanassche T, Verhamme P. Coagulation: At the heart of infective endocarditis. J Thromb Haemost 2020; 18:995-1008. [PMID: 31925863 DOI: 10.1111/jth.14736] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 01/02/2020] [Indexed: 12/11/2022]
Abstract
Infective endocarditis is a life-threatening and enigmatic disease with a mortality of 30% and a pathophysiology that is poorly understood. However, at its core, an endocarditis lesion is mainly a fibrin and platelet blood clot infested with bacteria, clinging at the cardiac valves. Infective endocarditis therefore serves as a paradigm of immunothrombosis gone wrong. Immunothrombosis refers to the entanglement of the coagulation system with innate immunity and the role of coagulation in the isolation and clearance of invading pathogens. However, in the case of infective endocarditis, instead of containing the infection, immunothrombosis inadvertently creates the optimal shelter from the immune system and allows some bacteria to grow almost unimpeded. In every step of the disease, the coagulation system is heavily involved. It mediates the initial adhesion of bacteria to the leaflets, fuels the growth and maturation of a vegetation, and facilitates complications such as embolization and valve destruction. In addition, the number one cause of infective endocarditis, Staphylococcus aureus, has proven to be a true manipulator of immunothrombosis and thrives in the fibrin rich environment of an endocarditis vegetation. Considering its central role in infective endocarditis, the coagulation system is an attractive therapeutic target for this deadly disease. There is, however, a very delicate balance at play and the use of antithrombotic drugs in patients with endocarditis is often accompanied with a high bleeding risk.
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Affiliation(s)
- Laurens Liesenborghs
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Severien Meyers
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Thomas Vanassche
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Peter Verhamme
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
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27
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John A, Robador JR, Vidal-Y-Sy S, Houdek P, Wladykowski E, Günes C, Bolenz C, Schneider SW, Bauer AT, Gorzelanny C. Urothelial Carcinoma of the Bladder Induces Endothelial Cell Activation and Hypercoagulation. Mol Cancer Res 2020; 18:1099-1109. [PMID: 32234826 DOI: 10.1158/1541-7786.mcr-19-1041] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 01/15/2020] [Accepted: 03/26/2020] [Indexed: 11/16/2022]
Abstract
Cancer-related venous thromboembolisms (VTE) are associated with metastasis and reduced survival in patients with urothelial cancer of the bladder. Although previous reports suggest the contribution of tissue factor and podoplanin, the mechanistic linkage between VTE and bladder cancer cell-derived molecules is unknown. Therefore, we compared distinct procoagulant pathways in four different cell lines. In vitro findings were further confirmed by microfluidic experiments mimicking the pathophysiology of tumor blood vessels and in tissue samples of patients with bladder cancer by transcriptome analysis and immunohistology. In vitro and microfluidic experiments identified bladder cancer-derived VEGF-A as highly procoagulant because it promoted the release of von Willebrand factor (VWF) from endothelial cells and thus platelet aggregation. In tissue sections from patients with bladder cancer, we found that VWF-mediated blood vessel occlusions were associated with a poor outcome. Transcriptome data further indicate that elevated expression levels of enzymes modulating VEGF-A availability were significantly connected to a decreased survival in patients with bladder cancer. In comparison with previously postulated molecular players, we identified tumor cell-derived VEGF-A and endothelial VWF as procoagulant mediators in bladder cancer. Therapeutic strategies that prevent the VEGF-A-mediated release of VWF may reduce tumor-associated hypercoagulation and metastasis in patients with bladder cancer. IMPLICATIONS: We identified the VEGF-A-mediated release of VWF from endothelial cells to be associated with bladder cancer progression.
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Affiliation(s)
- Axel John
- Department of Urology, University of Ulm, Ulm, Germany
| | - José R Robador
- Experimental Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sabine Vidal-Y-Sy
- Experimental Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Pia Houdek
- Experimental Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ewa Wladykowski
- Experimental Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Cagatay Günes
- Department of Urology, University of Ulm, Ulm, Germany
| | | | - Stefan W Schneider
- Experimental Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alexander T Bauer
- Experimental Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Gorzelanny
- Experimental Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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28
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Peetermans M, Meyers S, Liesenborghs L, Vanhoorelbeke K, De Meyer SF, Vandenbriele C, Lox M, Hoylaerts MF, Martinod K, Jacquemin M, Vanassche T, Verhamme P. Von Willebrand factor and ADAMTS13 impact on the outcome of Staphylococcus aureus sepsis. J Thromb Haemost 2020; 18:722-731. [PMID: 31758651 DOI: 10.1111/jth.14686] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 11/18/2019] [Indexed: 01/02/2023]
Abstract
BACKGROUND Previous clinical evidence correlates levels of von Willebrand factor (VWF) and its cleaving protease ADAMTS13 with outcome in septic patients. No previous studies addressed if VWF and ADAMTS13 affected the outcome of Staphylococcus aureus sepsis. OBJECTIVES We studied the role of VWF and ADAMTS13 in S. aureus sepsis both in patients and in mice. METHODS VWF levels and ADAMTS13 activity levels were measured in plasma samples from 89 S. aureus bacteremia patients by chemiluminescent assays and were correlated with clinical sepsis outcome parameters. In wild-type mice and mice deficient in VWF and ADAMTS13, we investigated the outcome of S. aureus sepsis and quantified bacterial clearance and organ microthrombi. RESULTS In patients with S. aureus bloodstream infections, high VWF levels and low ADAMTS13 activity levels correlated with disease severity and with parameters of inflammation and disseminated intravascular coagulation. In septic mice, VWF deficiency attenuated mortality, whereas ADAMTS13 deficiency increased mortality. Bacterial clearance was enhanced in VWF-deficient mice. The differences in mortality for the studied genotypes were associated with differential loads of organ microthrombi in both liver and kidneys. CONCLUSIONS In conclusion, this study reports the consistent relation of VWF, ADAMTS13 and their ratio to disease severity in patients and mice with S. aureus sepsis. Targeting VWF multimers and/or the relative ADAMTS13 deficiency that occurs in sepsis should be explored as a potential new therapeutic target in S. aureus endovascular infections.
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Affiliation(s)
- Marijke Peetermans
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Severien Meyers
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Laurens Liesenborghs
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Karen Vanhoorelbeke
- Laboratory for Thrombosis Research, University of Leuven campus Kulak Kortrijk, Kortrijk, Belgium
| | - Simon F De Meyer
- Laboratory for Thrombosis Research, University of Leuven campus Kulak Kortrijk, Kortrijk, Belgium
| | - Christophe Vandenbriele
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Marleen Lox
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Marc F Hoylaerts
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Kimberly Martinod
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Marc Jacquemin
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Thomas Vanassche
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Peter Verhamme
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
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Tan CAZ, Antypas H, Kline KA. Overcoming the challenge of establishing biofilms in vivo: a roadmap for Enterococci. Curr Opin Microbiol 2020; 53:9-18. [PMID: 32062025 DOI: 10.1016/j.mib.2020.01.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/10/2020] [Accepted: 01/15/2020] [Indexed: 12/28/2022]
Abstract
Enterococcus faecalis forms single and mixed-species biofilms on both tissue and medical devices in the host, often under exposure to fluid flow, giving rise to infections that are recalcitrant to treatment. The factors that drive enterococcal biofilm formation in the host, however, remain unclear. Recent reports in other pathogens show how surface sensing by bacteria can trigger the transition from planktonic to sessile lifestyle. Fluid flow can enhance initial adhesion, but also influence quorum sensing. Biofilm-specific factors, as well as biofilm size and extracellular polymeric substances, can compromise opsonization and phagocytosis. Bacterial interspecies synergy can create favorable conditions in the host for biofilm formation. Through these concepts, we define the knowledge gaps in understanding host-associated E. faecalis biofilm formation and propose a roadmap for future investigations.
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Affiliation(s)
- Casandra Ai Zhu Tan
- Singapore Centre for Environmental Life Sciences Engineering, School of Biological Sciences, Nanyang Technological University, Singapore
| | - Haris Antypas
- Singapore Centre for Environmental Life Sciences Engineering, School of Biological Sciences, Nanyang Technological University, Singapore
| | - Kimberly A Kline
- Singapore Centre for Environmental Life Sciences Engineering, School of Biological Sciences, Nanyang Technological University, Singapore.
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Ni W, Bao J, Mo B, Liu L, Li T, Pan G, Chen J, Zhou Z. Hemocytin facilitates host immune responses against Nosema bombycis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 103:103495. [PMID: 31618618 DOI: 10.1016/j.dci.2019.103495] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/09/2019] [Accepted: 09/09/2019] [Indexed: 06/10/2023]
Abstract
Invertebrates lack an adaptive immune response and thus are reliant on their innate immune response for eliminating invading pathogens. The innate immune responses of silkworms against the pathogen Nosema bombycis include: hemocyte aggregation, melanization, antimicrobial peptides, etc. In our current study, we discovered that a silkworm hemostasis-related protein, hemocytin, is up-regulated after Nosema bombycis infection. This novel finding lead to our hypothesis that hemocytin participates in immune responses against N. bombycis. We investigated this hypothesis by analyzing the adhesive effects of hemocytin to invading N. bombycis, and the hemocytin-mediated hemocyte aggregation and hemolymph melanization. We showed that hemocytin can adhere to the surface of N. bombycis, which facilitates the agglutination of N. bombycis and hemocytes as well as the subsequent melanization. Moreover, when we utilize RNAi technology to decrease in vivo hemocytin expression, we found that the proliferation of N. bombycis within the host significantly increased. These results support our hypothesis that hemocytin exerts pro-inflammatory effects by facilitating pathogen agglutination, along with hemocyte aggregation and melanization, to combat N. bombycis. Our study is the first to determine a function of hemocytin in innate immunity against N. bombycis. Moreover, our findings are of great importance to provide potential targets for developing novel strategy against microsporidia infection.
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Affiliation(s)
- Wenjia Ni
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Jialing Bao
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Biying Mo
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Lulu Liu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Tian Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Guoqing Pan
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Jie Chen
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China
| | - Zeyang Zhou
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China; Chongqing Key Laboratory of Microsporidia Infection and Control, Southwest University, Chongqing, China; Chongqing Normal University, Chongqing, China.
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31
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Abstract
Von Willebrand factor (VWF) and coagulation factor VIII (FVIII) circulate as a complex in plasma and have a major role in the hemostatic system. VWF has a dual role in hemostasis. It promotes platelet adhesion by anchoring the platelets to the subendothelial matrix of damaged vessels and it protects FVIII from proteolytic degradation. Moreover, VWF is an acute phase protein that has multiple roles in vascular inflammation and is massively secreted from Weibel-Palade bodies upon endothelial cell activation. Activated FVIII on the other hand, together with coagulation factor IX forms the tenase complex, an essential feature of the propagation phase of coagulation on the surface of activated platelets. VWF deficiency, either quantitative or qualitative, results in von Willebrand disease (VWD), the most common bleeding disorder. The deficiency of FVIII is responsible for Hemophilia A, an X-linked bleeding disorder. Here, we provide an overview on the role of the VWF-FVIII interaction in vascular physiology.
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Affiliation(s)
- Klytaimnistra Kiouptsi
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Langenbeckstrasse 1, Building 708, 55131, Mainz, Germany
| | - Christoph Reinhardt
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Langenbeckstrasse 1, Building 708, 55131, Mainz, Germany.
- German Center for Cardiovascular Research (DZHK), Partner Site RheinMain, Mainz, Germany.
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A new role for host annexin A2 in establishing bacterial adhesion to vascular endothelial cells: lines of evidence from atomic force microscopy and an in vivo study. J Transl Med 2019; 99:1650-1660. [PMID: 31253864 PMCID: PMC6913097 DOI: 10.1038/s41374-019-0284-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 05/08/2019] [Accepted: 05/20/2019] [Indexed: 01/27/2023] Open
Abstract
Understanding bacterial adhesion is challenging and critical to our understanding of the initial stages of the pathogenesis of endovascular bacterial infections. The vascular endothelial cell (EC) is the main target of Rickettsia, an obligately intracellular bacterium that causes serious systemic disease in humans and animals. But the mechanism(s) underlying bacterial adherence to ECs under shear stress from flowing blood prior to activation are unknown for any bacteria. Although host surface annexin a2 (ANXA2) has been identified to participate in efficient bacterial invasion of epithelial cells, direct evidence is lacking in the field of bacterial infections of ECs. In the present study, we employ a novel, anatomically based, in vivo quantitative bacterial-adhesion-to-vascular-EC system, combined with atomic force microscopy (AFM), to examine the role of endothelial luminal surface ANXA2 during rickettsial adherence to ECs. We also examined whether ANXA2 antibody affected binding of Staphylococcus aureus to ECs. We found that deletion of ANXA2 impeded rickettsial attachment to the ECs in vitro and blocked rickettsial adherence to the blood vessel luminal surface in vivo. The AFM studies established that EC surface ANXA2 acts as an adherence receptor for rickettsiae, and that rickettsial adhesin OmpB is the associated bacterial ligand. Furthermore, pretreatment of ECs with anti-ANXA2 antibody reduced EC surface-associated S. aureus. We conclude that the endothelial surface ANXA2 plays an important role in initiating pathogen-host interactions, ultimately leading to bacterial anchoring on the vascular luminal surface.
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The endothelial glycocalyx anchors von Willebrand factor fibers to the vascular endothelium. Blood Adv 2019; 2:2347-2357. [PMID: 30237293 DOI: 10.1182/bloodadvances.2017013995] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 08/03/2018] [Indexed: 12/22/2022] Open
Abstract
The dynamic change from a globular conformation to an elongated fiber determines the ability of von Willebrand factor (VWF) to trap platelets. Fiber formation is favored by the anchorage of VWF to the endothelial cell surface, and VWF-platelet aggregates on the endothelium contribute to inflammation, infection, and tumor progression. Although P-selectin and ανβ3-integrins may bind VWF, their precise role is unclear, and additional binding partners have been proposed. In the present study, we evaluated whether the endothelial glycocalyx anchors VWF fibers to the endothelium. Using microfluidic experiments, we showed that stabilization of the endothelial glycocalyx by chitosan oligosaccharides or overexpression of syndecan-1 (SDC-1) significantly supports the binding of VWF fibers to endothelial cells. Heparinase-mediated degradation or impaired synthesis of heparan sulfate (HS), a major component of the endothelial glycocalyx, reduces VWF fiber-dependent platelet recruitment. Molecular interaction studies using flow cytometry and live-cell fluorescence microscopy provided further evidence that VWF binds to HS linked to SDC-1. In a murine melanoma model, we found that protection of the endothelial glycocalyx through the silencing of heparanase increases the number of VWF fibers attached to the wall of tumor blood vessels. In conclusion, we identified HS chains as a relevant binding factor for VWF fibers at the endothelial cell surface in vitro and in vivo.
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Wheeler JD, Secchi E, Rusconi R, Stocker R. Not Just Going with the Flow: The Effects of Fluid Flow on Bacteria and Plankton. Annu Rev Cell Dev Biol 2019; 35:213-237. [PMID: 31412210 DOI: 10.1146/annurev-cellbio-100818-125119] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Microorganisms often live in habitats characterized by fluid flow, from lakes and oceans to soil and the human body. Bacteria and plankton experience a broad range of flows, from the chaotic motion characteristic of turbulence to smooth flows at boundaries and in confined environments. Flow creates forces and torques that affect the movement, behavior, and spatial distribution of microorganisms and shapes the chemical landscape on which they rely for nutrient acquisition and communication. Methodological advances and closer interactions between physicists and biologists have begun to reveal the importance of flow-microorganism interactions and the adaptations of microorganisms to flow. Here we review selected examples of such interactions from bacteria, phytoplankton, larvae, and zooplankton. We hope that this article will serve as a blueprint for a more in-depth consideration of the effects of flow in the biology of microorganisms and that this discussion will stimulate further multidisciplinary effort in understanding this important component of microorganism habitats.
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Affiliation(s)
- Jeanette D Wheeler
- Institute of Environmental Engineering, Department of Civil, Environmental, and Geomatic Engineering, ETH Zürich, 8093 Zürich, Switzerland;
| | - Eleonora Secchi
- Institute of Environmental Engineering, Department of Civil, Environmental, and Geomatic Engineering, ETH Zürich, 8093 Zürich, Switzerland;
| | - Roberto Rusconi
- Department of Biomedical Sciences, Humanitas University, 20090 Pieve Emanuele (MI), Italy.,Humanitas Clinical and Research Center-IRCCS, 20089 Rozzano (MI), Italy
| | - Roman Stocker
- Institute of Environmental Engineering, Department of Civil, Environmental, and Geomatic Engineering, ETH Zürich, 8093 Zürich, Switzerland;
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35
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Liu X, Gorzelanny C, Schneider SW. Platelets in Skin Autoimmune Diseases. Front Immunol 2019; 10:1453. [PMID: 31333641 PMCID: PMC6620619 DOI: 10.3389/fimmu.2019.01453] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 06/10/2019] [Indexed: 12/11/2022] Open
Abstract
Systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and small vessel vasculitis are three autoimmune diseases frequently manifested in the skin. They share common pathogenic features, including production of autoantibodies, loss of tolerance to self-antigens, tissue necrosis and fibrosis, vasculopathy and activation of the coagulation system. Platelets occupy a central part within the coagulation cascade and are well-recognized for their hemostatic role. However, recent cumulative evidence implicates their additional and multifaceted immunoregulatory functions. Platelets express immune receptors and they store growth factors, cytokines, and chemokines in their granules enabling a significant contribution to inflammation. A plethora of activating triggers such as damage associated molecular patterns (DAMPs) released from damaged endothelial cells, immune complexes, or complement effector molecules can mediate platelet activation. Activated platelets further foster an inflammatory environment and the crosstalk with the endothelium and leukocytes by the release of immunoactive molecules and microparticles. Further insight into the pathogenic implications of platelet activation will pave the way for new therapeutic strategies targeting autoimmune diseases. In this review, we discuss the inflammatory functions of platelets and their mechanistic contribution to the pathophysiology of SSc, ANCA associated small vessel vasculitis and other autoimmune diseases affecting the skin.
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Affiliation(s)
- Xiaobo Liu
- Department of Dermatology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.,Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Gorzelanny
- Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan W Schneider
- Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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36
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Kwiecinski JM, Crosby HA, Valotteau C, Hippensteel JA, Nayak MK, Chauhan AK, Schmidt EP, Dufrêne YF, Horswill AR. Staphylococcus aureus adhesion in endovascular infections is controlled by the ArlRS-MgrA signaling cascade. PLoS Pathog 2019; 15:e1007800. [PMID: 31116795 PMCID: PMC6548404 DOI: 10.1371/journal.ppat.1007800] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 06/04/2019] [Accepted: 04/30/2019] [Indexed: 12/31/2022] Open
Abstract
Staphylococcus aureus is a leading cause of endovascular infections. This bacterial pathogen uses a diverse array of surface adhesins to clump in blood and adhere to vessel walls, leading to endothelial damage, development of intravascular vegetations and secondary infectious foci, and overall disease progression. In this work, we describe a novel strategy used by S. aureus to control adhesion and clumping through activity of the ArlRS two-component regulatory system, and its downstream effector MgrA. Utilizing a combination of in vitro cellular assays, and single-cell atomic force microscopy, we demonstrated that inactivation of this ArlRS—MgrA cascade inhibits S. aureus adhesion to a vast array of relevant host molecules (fibrinogen, fibronectin, von Willebrand factor, collagen), its clumping with fibrinogen, and its attachment to human endothelial cells and vascular structures. This impact on S. aureus adhesion was apparent in low shear environments, and in physiological levels of shear stress, as well as in vivo in mouse models. These effects were likely mediated by the de-repression of giant surface proteins Ebh, SraP, and SasG, caused by inactivation of the ArlRS—MgrA cascade. In our in vitro assays, these giant proteins collectively shielded the function of other surface adhesins and impaired their binding to cognate ligands. Finally, we demonstrated that the ArlRS—MgrA regulatory cascade is a druggable target through the identification of a small-molecule inhibitor of ArlRS signaling. Our findings suggest a novel approach for the pharmacological treatment and prevention of S. aureus endovascular infections through targeting the ArlRS—MgrA regulatory system. Adhesion is central to the success of Staphylococcus aureus as a bacterial pathogen. We describe a novel mechanism through which S. aureus alters adhesion to ligands by regulating expression of giant inhibitory surface proteins. These giant proteins shield normal surface adhesins, preventing binding to ligands commonly found in the bloodstream and vessel walls. Using this unique regulatory scheme, S. aureus can bypass the need for individualized regulation of numerous adhesins to control overall adhesive properties. Our study establishes the importance of these giant proteins for S. aureus pathogenesis and demonstrates that a single regulatory cascade can be targeted for treating infections.
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Affiliation(s)
- Jakub M. Kwiecinski
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Heidi A. Crosby
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Claire Valotteau
- Institute of Life Sciences, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Joseph A. Hippensteel
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Manasa K. Nayak
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Anil K. Chauhan
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, United States of America
| | - Eric P. Schmidt
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, United States of America
| | - Yves F. Dufrêne
- Institute of Life Sciences, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Wallonia, Belgium
| | - Alexander R. Horswill
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, United States of America
- Department of Veterans Affairs Eastern Colorado Healthcare System, Denver, Colorado, United States of America
- * E-mail:
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37
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Binding of Staphylococcus aureus Protein A to von Willebrand Factor Is Regulated by Mechanical Force. mBio 2019; 10:mBio.00555-19. [PMID: 31040240 PMCID: PMC6495375 DOI: 10.1128/mbio.00555-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Staphylococcus aureus protein A (SpA) binds to von Willebrand factor (vWF) under flow. While vWF binding to SpA plays a role in S. aureus adherence to platelets and endothelial cells under shear stress, the molecular basis of this stress-dependent interaction has not yet been elucidated. Here we show that the SpA-vWF interaction is regulated by a new force-dependent mechanism. The results suggest that mechanical extension of vWF may lead to the exposure of a high-affinity cryptic SpA-binding site, consistent with the shear force-controlled functions of vWF. Moreover, strong binding may be promoted by force-induced structural changes in the SpA domains. This study highlights the role of mechanoregulation in controlling the adhesion of S. aureus and shows promise for the design of small inhibitors capable of blocking colonization under high shear stress. Binding of Staphylococcus aureus to the large plasma glycoprotein von Willebrand factor (vWF) is controlled by hydrodynamic flow conditions. Currently, we know little about the molecular details of this shear-stress-dependent interaction. Using single-molecule atomic force microscopy, we demonstrate that vWF binds to the S. aureus surface protein A (SpA) via a previously undescribed force-sensitive mechanism. We identify an extremely strong SpA-vWF interaction, capable of withstanding forces of ∼2 nN, both in laboratory and in clinically relevant methicillin-resistant S. aureus (MRSA) strains. Strong bonds are activated by mechanical stress, consistent with flow experiments revealing that bacteria adhere in larger amounts to vWF surfaces when the shear rate is increased. We suggest that force-enhanced adhesion may involve conformational changes in vWF. Under force, elongation of vWF may lead to the exposure of a high-affinity cryptic SpA-binding site to which bacteria firmly attach. In addition, force-induced structural changes in the SpA domains may also promote strong, high-affinity binding. This force-regulated interaction might be of medical importance as it may play a role in bacterial adherence to platelets and to damaged blood vessels.
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38
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Jagau H, Behrens IK, Lahme K, Lorz G, Köster RW, Schneppenheim R, Obser T, Brehm MA, König G, Kohler TP, Rohde M, Frank R, Tegge W, Fulde M, Hammerschmidt S, Steinert M, Bergmann S. Von Willebrand Factor Mediates Pneumococcal Aggregation and Adhesion in Blood Flow. Front Microbiol 2019; 10:511. [PMID: 30972039 PMCID: PMC6443961 DOI: 10.3389/fmicb.2019.00511] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 02/27/2019] [Indexed: 12/24/2022] Open
Abstract
Streptococcus pneumoniae is a major cause of community acquired pneumonia and septicaemia in humans. These diseases are frequently associated with thromboembolic cardiovascular complications. Pneumococci induce the exocytosis of endothelial Weibel-Palade Bodies and thereby actively stimulate the release of von Willebrand factor (VWF), which is an essential glycoprotein of the vascular hemostasis. Both, the pneumococcus induced pulmonary inflammation and the thromboembolytic complications are characterized by a dysbalanced hemostasis including a marked increase in VWF plasma concentrations. Here, we describe for the first time VWF as a novel interaction partner of capsulated and non-encapsulated pneumococci. Moreover, cell culture infection analyses with primary endothelial cells characterized VWF as bridging molecule that mediates bacterial adherence to endothelial cells in a heparin-sensitive manner. Due to the mechanoresponsive changes of the VWF protein conformation and multimerization status, which occur in the blood stream, we used a microfluidic pump system to generate shear flow-induced multimeric VWF strings on endothelial cell surfaces and analyzed attachment of RFP-expressing pneumococci in flow. By applying immunofluorescence visualization and additional electron microscopy, we detected a frequent and enduring bacterial attachment to the VWF strings. Bacterial attachment to the endothelium was confirmed in vivo using a zebrafish infection model, which is described in many reports and acknowledged as suitable model to study hemostasis mechanisms and protein interactions of coagulation factors. Notably, we visualized the recruitment of zebrafish-derived VWF to the surface of pneumococci circulating in the blood stream and detected a VWF-dependent formation of bacterial aggregates within the vasculature of infected zebrafish larvae. Furthermore, we identified the surface-exposed bacterial enolase as pneumococcal VWF binding protein, which interacts with the VWF domain A1 and determined the binding kinetics by surface plasmon resonance. Subsequent epitope mapping using an enolase peptide array indicates that the peptide 181YGAEIFHALKKILKS195 might serve as a possible core sequence of the VWF interaction site. In conclusion, we describe a VWF-mediated mechanism for pneumococcal anchoring within the bloodstream via surface-displayed enolase, which promotes intravascular bacterial aggregation.
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Affiliation(s)
- Hilger Jagau
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Ina-Kristin Behrens
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Karen Lahme
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Georgina Lorz
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
| | - Reinhard W Köster
- Zoological Institute, Technische Universität Braunschweig, Braunschweig, Germany
| | - Reinhard Schneppenheim
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf (UKE Hamburg), Hamburg, Germany
| | - Tobias Obser
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf (UKE Hamburg), Hamburg, Germany
| | - Maria A Brehm
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf (UKE Hamburg), Hamburg, Germany
| | - Gesa König
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf (UKE Hamburg), Hamburg, Germany
| | - Thomas P Kohler
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Universität Greifswald, Greifswald, Germany
| | - Manfred Rohde
- Helmholtz Centre for Infection Research, Central Facility for Microscopy, Braunschweig, Germany
| | - Ronald Frank
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Werner Tegge
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Marcus Fulde
- Centre for Infection Medicine, Institute of Microbiology and Epizootics, Freie Universität Berlin, Berlin, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Universität Greifswald, Greifswald, Germany
| | - Michael Steinert
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany.,Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Simone Bergmann
- Institute of Microbiology, Technische Universität Braunschweig, Braunschweig, Germany
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39
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Feuillie C, Vitry P, McAleer MA, Kezic S, Irvine AD, Geoghegan JA, Dufrêne YF. Adhesion of Staphylococcus aureus to Corneocytes from Atopic Dermatitis Patients Is Controlled by Natural Moisturizing Factor Levels. mBio 2018; 9:e01184-18. [PMID: 30108169 PMCID: PMC6094479 DOI: 10.1128/mbio.01184-18] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/06/2018] [Indexed: 02/06/2023] Open
Abstract
The bacterial pathogen Staphylococcus aureus plays an important role in atopic dermatitis (AD), a chronic disorder that mostly affects children. Colonization of the skin of AD patients by S. aureus exacerbates the disease, but the molecular determinants of the bacterium-skin adhesive interactions are poorly understood. Specifically, reduced levels of natural moisturizing factor (NMF) in the stratum corneum have been shown to be associated with more severe AD symptoms, but whether this is directly related to S. aureus adhesion is still an open question. Here, we demonstrate a novel relationship between NMF expression in AD skin and strength of bacterial adhesion. Low-NMF corneocytes, unlike high-NMF ones, are covered by a dense layer of nanoscale villus protrusions. S. aureus bacteria isolated from AD skin bind much more strongly to corneocytes when the NMF level is reduced. Strong binding forces originate from a specific interaction between the bacterial adhesion clumping factor B (ClfB) and skin ligands. Remarkably, mechanical tension dramatically strengthens ClfB-mediated adhesion, as observed with catch bonds, demonstrating that physical stress plays a role in promoting colonization of AD skin by S. aureus Collectively, our findings demonstrate that patient NMF levels regulate the strength of S. aureus-corneocyte adhesion, the first step in skin colonization, and suggest that the ClfB binding mechanism could represent a potential target for new therapeutic treatments.IMPORTANCE Bacterium-skin interactions play important roles in skin disorders, yet their molecular details are poorly understood. In this study, we decipher the molecular forces at play during adhesion of Staphylococcus aureus to skin corneocytes in the clinically important context of atopic dermatitis (AD), also known as eczema. We identify a unique relationship between the level of natural moisturizing factor (NMF) in the skin and the strength of bacterium-corneocyte adhesion. Bacterial adhesion is primarily mediated by the surface protein clumping factor B (ClfB) and is enhanced by physical stress, highlighting the role of protein mechanobiology in skin colonization. Similar to a catch bond behavior, this mechanism represents a promising target for the development of novel antistaphylococcal agents.
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Affiliation(s)
- Cécile Feuillie
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Pauline Vitry
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Maeve A McAleer
- National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland
- Pediatric Dermatology, Our Lady's Children's Hospital, Dublin, Ireland
- Clinical Medicine, Trinity College Dublin, Dublin, Ireland
| | - Sanja Kezic
- Coronel Institute of Occupational Health, Academic Medical Center, Amsterdam, The Netherlands
| | - Alan D Irvine
- National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland
- Pediatric Dermatology, Our Lady's Children's Hospital, Dublin, Ireland
- Clinical Medicine, Trinity College Dublin, Dublin, Ireland
| | - Joan A Geoghegan
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Yves F Dufrêne
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Wavre, Belgium
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40
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Nicolay JP, Thorn V, Daniel C, Amann K, Siraskar B, Lang F, Hillgruber C, Goerge T, Hoffmann S, Gorzelanny C, Huck V, Mess C, Obser T, Schneppenheim R, Fleming I, Schneider MF, Schneider SW. Cellular stress induces erythrocyte assembly on intravascular von Willebrand factor strings and promotes microangiopathy. Sci Rep 2018; 8:10945. [PMID: 30026593 PMCID: PMC6053440 DOI: 10.1038/s41598-018-28961-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 07/01/2018] [Indexed: 11/17/2022] Open
Abstract
Microangiopathy with subsequent organ damage represents a major complication in several diseases. The mechanisms leading to microvascular occlusion include von Willebrand factor (VWF), notably the formation of ultra-large von Willebrand factor fibers (ULVWFs) and platelet aggregation. To date, the contribution of erythrocytes to vascular occlusion is incompletely clarified. We investigated the platelet-independent interaction between stressed erythrocytes and ULVWFs and its consequences for microcirculation and organ function under dynamic conditions. In response to shear stress, erythrocytes interacted strongly with VWF to initiate the formation of ULVWF/erythrocyte aggregates via the binding of Annexin V to the VWF A1 domain. VWF-erythrocyte adhesion was attenuated by heparin and the VWF-specific protease ADAMTS13. In an in vivo model of renal ischemia/reperfusion injury, erythrocytes adhered to capillaries of wild-type but not VWF-deficient mice and later resulted in less renal damage. In vivo imaging in mice confirmed the adhesion of stressed erythrocytes to the vessel wall. Moreover, enhanced eryptosis rates and increased VWF binding were detected in blood samples from patients with chronic renal failure. Our study demonstrates that stressed erythrocytes have a pronounced binding affinity to ULVWFs. The discovered mechanisms suggest that erythrocytes are essential for the pathogenesis of microangiopathies and renal damage by actively binding to ULVWFs.
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Affiliation(s)
- Jan P Nicolay
- Department of Dermatology, Venereology and Allergy, University Medical Center Mannheim, Ruprecht-Karls-University of Heidelberg, Mannheim, Germany. .,Division of Immunogenetics, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Verena Thorn
- Department of Dermatology, Venereology and Allergy, University Medical Center Mannheim, Ruprecht-Karls-University of Heidelberg, Mannheim, Germany
| | - Christoph Daniel
- Department of Nephropathology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | - Kerstin Amann
- Department of Nephropathology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Erlangen, Germany
| | | | - Florian Lang
- Department of Physiology, University of Tübingen, Tübingen, Germany
| | - Carina Hillgruber
- Department of Dermatology, University Hospital Münster, Münster, Germany
| | - Tobias Goerge
- Department of Dermatology, University Hospital Münster, Münster, Germany
| | - Stefan Hoffmann
- Institute of Plant Biology and Biotechnology (IBBP), Westfälische Wilhelms-Universität Münster, Münster, Germany
| | - Christian Gorzelanny
- Department of Dermatology, Venereology and Allergy, University Medical Center Mannheim, Ruprecht-Karls-University of Heidelberg, Mannheim, Germany.,Department of Dermatology and Venerology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Volker Huck
- Department of Dermatology, Venereology and Allergy, University Medical Center Mannheim, Ruprecht-Karls-University of Heidelberg, Mannheim, Germany.,Department of Dermatology and Venerology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Mess
- Department of Dermatology and Venerology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tobias Obser
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Reinhard Schneppenheim
- Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ingrid Fleming
- Institute for Vascular Signalling, Centre for Molecular Medicine, Goethe University, Frankfurt am Main, Germany
| | | | - Stefan W Schneider
- Department of Dermatology and Venerology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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41
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Liesenborghs L, Verhamme P, Vanassche T. Staphylococcus aureus, master manipulator of the human hemostatic system. J Thromb Haemost 2018; 16:441-454. [PMID: 29251820 DOI: 10.1111/jth.13928] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Indexed: 12/15/2022]
Abstract
The coagulation system does not only offer protection against bleeding, but also aids in our defense against invading microorganisms. The hemostatic system and innate immunity are strongly entangled, which explains why so many infections are complicated by either bleeding or thrombosis. Staphylococcus aureus (S. aureus), currently the most deadly infectious agent in the developed world, causes devastating intravascular infections such as sepsis and infective endocarditis. During these infections S. aureus comes in close contact with the host hemostatic system and proves to be a master in manipulating coagulation. The coagulases of S. aureus directly induce coagulation by activating prothrombin. S. aureus also manipulates fibrinolysis by triggering plasminogen activation via staphylokinase. Furthermore, S. aureus binds and activates platelets and interacts with key coagulation proteins such as fibrin(ogen), fibronectin and von Willebrand factor. By manipulating the coagulation system S. aureus gains a significant advantage over the host defense mechanisms. Studying the interplay between S. aureus and the hemostatic system can therefore lead to new innovative therapies for battling S. aureus infections.
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Affiliation(s)
- L Liesenborghs
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, KULeuven - University Hospitals Leuven, Leuven, Belgium
| | - P Verhamme
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, KULeuven - University Hospitals Leuven, Leuven, Belgium
| | - T Vanassche
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, KULeuven - University Hospitals Leuven, Leuven, Belgium
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42
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Hoerr V, Franz M, Pletz MW, Diab M, Niemann S, Faber C, Doenst T, Schulze PC, Deinhardt-Emmer S, Löffler B. S. aureus endocarditis: Clinical aspects and experimental approaches. Int J Med Microbiol 2018. [PMID: 29526448 DOI: 10.1016/j.ijmm.2018.02.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Infective endocarditis (IE) is a life-threatening disease, caused by septic vegetations and inflammatory foci on the surface of the endothelium and the valves. Due to its complex and often indecisive presentation the mortality rate is still about 30%. Most frequently bacterial microorganisms entering the bloodstream are the underlying origin of the intracardiac infection. While the disease was primarily restricted to younger patients suffering from rheumatic heart streptococci infections, new at risk categories for Staphylococcus (S.) aureus infections arose over the last years. Rising patient age, increasing drug resistance, intensive treatment conditions such as renal hemodialysis, immunosuppression and long term indwelling central venous catheters but also the application of modern cardiac device implants and valve prosthesis have led to emerging incidences of S. aureus IE in health care settings and community. The aetiologic change has impact on the pathophysiology of IE, the clinical presentation and the overall patient management. Despite intensive research on appropriate in vitro and in vivo models of IE and gained knowledge about the fundamental mechanisms in the formation of bacterial vegetations and extracardiac complications, improved understanding of relevant bacterial virulence factors and triggered host immune responses is required to help developing novel antipathogenic treatment strategies and pathogen specific diagnostic markers. In this review, we summarize and discuss the two main areas affected by the changing patient demographics and provide first, recent knowledge about the pathogenic strategies of S. aureus in the induction of IE, including available experimental models of IE used to study host-pathogen interactions and diagnostic and therapeutic targets. In a second focus we present diagnostic (imaging) regimens for patients with S. aureus IE according to current guidelines as well as treatment strategies and surgical recommendations.
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Affiliation(s)
- V Hoerr
- Institute of Medical Microbiology, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany.
| | - M Franz
- Department of Internal Medicine I, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
| | - M W Pletz
- Institute for Infectious Diseases and Infection Control, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
| | - M Diab
- Department of Cardiothoracic Surgery, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
| | - S Niemann
- Institute of Medical Microbiology, University Hospital Münster, Domagkstr. 10, 48149 Münster, Germany
| | - C Faber
- Department of Clinical Radiology, University Hospital Münster, Albert-Schweitzer-Campus 1, Building A16, 48149 Münster, Germany
| | - T Doenst
- Department of Cardiothoracic Surgery, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
| | - P C Schulze
- Department of Internal Medicine I, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
| | - S Deinhardt-Emmer
- Institute of Medical Microbiology, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
| | - B Löffler
- Institute of Medical Microbiology, Jena University Hospital, Am Klinikum 1, 07747 Jena, Germany
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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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Vitry P, Valotteau C, Feuillie C, Bernard S, Alsteens D, Geoghegan JA, Dufrêne YF. Force-Induced Strengthening of the Interaction between Staphylococcus aureus Clumping Factor B and Loricrin. mBio 2017; 8:e01748-17. [PMID: 29208742 PMCID: PMC5717387 DOI: 10.1128/mbio.01748-17] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 10/27/2017] [Indexed: 02/02/2023] Open
Abstract
Bacterial pathogens that colonize host surfaces are subjected to physical stresses such as fluid flow and cell surface contacts. How bacteria respond to such mechanical cues is an important yet poorly understood issue. Staphylococcus aureus uses a repertoire of surface proteins to resist shear stress during the colonization of host tissues, but whether their adhesive functions can be modulated by physical forces is not known. Here, we show that the interaction of S. aureus clumping factor B (ClfB) with the squamous epithelial cell envelope protein loricrin is enhanced by mechanical force. We find that ClfB mediates S. aureus adhesion to loricrin through weak and strong molecular interactions both in a laboratory strain and in a clinical isolate. Strong forces (~1,500 pN), among the strongest measured for a receptor-ligand bond, are consistent with a high-affinity "dock, lock, and latch" binding mechanism involving dynamic conformational changes in the adhesin. Notably, we demonstrate that the strength of the ClfB-loricrin bond increases as mechanical force is applied. These findings favor a two-state model whereby bacterial adhesion to loricrin is enhanced through force-induced conformational changes in the ClfB molecule, from a weakly binding folded state to a strongly binding extended state. This force-sensitive mechanism may provide S. aureus with a means to finely tune its adhesive properties during the colonization of host surfaces, helping cells to attach firmly under high shear stress and to detach and spread under low shear stress.IMPORTANCEStaphylococcus aureus colonizes the human skin and the nose and can cause various disorders, including superficial skin lesions and invasive infections. During nasal colonization, the S. aureus surface protein clumping factor B (ClfB) binds to the squamous epithelial cell envelope protein loricrin, but the molecular interactions involved are poorly understood. Here, we unravel the molecular mechanism guiding the ClfB-loricrin interaction. We show that the ClfB-loricrin bond is remarkably strong, consistent with a high-affinity "dock, lock, and latch" binding mechanism. We discover that the ClfB-loricrin interaction is enhanced under tensile loading, thus providing evidence that the function of an S. aureus surface protein can be activated by physical stress.
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Affiliation(s)
- Pauline Vitry
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Claire Valotteau
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Cécile Feuillie
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Simon Bernard
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - David Alsteens
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Joan A Geoghegan
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Yves F Dufrêne
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Wavre, Belgium
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45
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Grønnemose RB, Saederup KL, Kolmos HJ, Hansen SWK, Asferg CA, Rasmussen KJ, Palarasah Y, Andersen TE. A novel in vitro model for haematogenous spreading ofS. aureusdevice biofilms demonstrating clumping dispersal as an advantageous dissemination mechanism. Cell Microbiol 2017; 19. [DOI: 10.1111/cmi.12785] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 07/28/2017] [Indexed: 01/07/2023]
Affiliation(s)
- R. B. Grønnemose
- Department of Clinical Microbiology; University of Southern Denmark and Odense University Hospital; Odense Denmark
| | - K. L. Saederup
- Department of Cancer and Inflammation Research; University of Southern Denmark; Odense Denmark
| | - H. J. Kolmos
- Department of Clinical Microbiology; University of Southern Denmark and Odense University Hospital; Odense Denmark
| | - S. W. K. Hansen
- Department of Cancer and Inflammation Research; University of Southern Denmark; Odense Denmark
| | - C. A. Asferg
- Department of Clinical Microbiology; University of Southern Denmark and Odense University Hospital; Odense Denmark
| | - K. J. Rasmussen
- Department of Cancer and Inflammation Research; University of Southern Denmark; Odense Denmark
| | - Y. Palarasah
- Unit for Thrombosis Research, Department of Clinical Biochemistry; University of Southern Denmark; Esbjerg Denmark
| | - T. E. Andersen
- Department of Clinical Microbiology; University of Southern Denmark and Odense University Hospital; Odense Denmark
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46
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C1q/TNF-related protein 1 promotes endothelial barrier dysfunction under disturbed flow. Biochem Biophys Res Commun 2017. [DOI: 10.1016/j.bbrc.2017.06.081] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Gragnano F, Crisci M, Bigazzi MC, Bianchi R, Sperlongano S, Natale F, Fimiani F, Concilio C, Cesaro A, Pariggiano I, Diana V, Limongelli G, Cirillo P, Russo M, Golia E, Calabrò P. Von Willebrand Factor as a Novel Player in Valvular Heart Disease: From Bench to Valve Replacement. Angiology 2017; 69:103-112. [PMID: 28481153 DOI: 10.1177/0003319717708070] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
von Willebrand Factor (vWF) is a well-known mediator of hemostasis and vascular inflammation. Its dynamic modulation in the bloodstream, according to hemodynamic conditions, makes it an appealing biomarker in patients with valvular heart disease (VHD). Recent studies highlight the close connection between vWF and VHD, with possible implications in the pathogenesis of VHD, promoting valve aging and calcification or favoring the development of infective endocarditis. Moreover, vWF has been recently proposed as a new diagnostic and prognostic tool in patients with valve stenosis or regurgitation, showing a strict correlation with severity of valve disease, outcome, and bleeding (Heyde syndrome). A novel role for vWF is also emerging in patients undergoing percutaneous or surgical valve repair/replacement to select and stratify patients, evaluate periprocedural bleeding risk, and detect procedural complications. We also report our single-center experience, suggesting, for the first time, possible clinical implications for vWF in percutaneous mitral valve repair (MitraClip). This review summarizes recent advances in the role of vWF in VHD with an updated overview going from bench to operating room.
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Affiliation(s)
- Felice Gragnano
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Mario Crisci
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Maurizio Cappelli Bigazzi
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Renatomaria Bianchi
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Simona Sperlongano
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Francesco Natale
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Fabio Fimiani
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Claudia Concilio
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Arturo Cesaro
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Ivana Pariggiano
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Vincenzo Diana
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Giuseppe Limongelli
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Plinio Cirillo
- 2 Department of Advanced Biological Sciences, Federico II University, Naples, Italy
| | - Mariagiovanna Russo
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Enrica Golia
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Paolo Calabrò
- 1 Division of Cardiology, Department of Cardio-thoracic and Respiratory Sciences, A.O. dei Colli Monaldi Hospital, University of Campania "Luigi Vanvitelli", Naples, Italy
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Claes J, Liesenborghs L, Peetermans M, Veloso TR, Missiakas D, Schneewind O, Mancini S, Entenza JM, Hoylaerts MF, Heying R, Verhamme P, Vanassche T. Clumping factor A, von Willebrand factor-binding protein and von Willebrand factor anchor Staphylococcus aureus to the vessel wall. J Thromb Haemost 2017; 15:1009-1019. [PMID: 28182324 PMCID: PMC6232194 DOI: 10.1111/jth.13653] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Indexed: 01/10/2023]
Abstract
Essentials Staphylococcus aureus (S. aureus) binds to endothelium via von Willebrand factor (VWF). Secreted VWF-binding protein (vWbp) mediates S. aureus adhesion to VWF under shear stress. vWbp interacts with VWF and the Sortase A-dependent surface protein Clumping factor A (ClfA). VWF-vWbp-ClfA anchor S. aureus to vascular endothelium under shear stress. SUMMARY Objective When establishing endovascular infections, Staphylococcus aureus (S. aureus) overcomes shear forces of flowing blood by binding to von Willebrand factor (VWF). Staphylococcal VWF-binding protein (vWbp) interacts with VWF, but it is unknown how this secreted protein binds to the bacterial cell wall. We hypothesized that vWbp interacts with a staphylococcal surface protein, mediating the adhesion of S. aureus to VWF and vascular endothelium under shear stress. Methods We studied the binding of S. aureus to vWbp, VWF and endothelial cells in a micro-parallel flow chamber using various mutants deficient in Sortase A (SrtA) and SrtA-dependent surface proteins, and Lactococcus lactis expressing single staphylococcal surface proteins. In vivo adhesion of bacteria was evaluated in the murine mesenteric circulation using real-time intravital vascular microscopy. Results vWbp bridges the bacterial cell wall and VWF, allowing shear-resistant binding of S. aureus to inflamed or damaged endothelium. Absence of SrtA and Clumping factor A (ClfA) reduced adhesion of S. aureus to vWbp, VWF and activated endothelial cells. ADAMTS-13 and an anti-VWF A1 domain antibody, when combined, reduced S. aureus adhesion to activated endothelial cells by 90%. Selective overexpression of ClfA in the membrane of Lactococcus lactis enabled these bacteria to bind to VWF and activated endothelial cells but only in the presence of vWbp. Absence of ClfA abolished bacterial adhesion to the activated murine vessel wall. Conclusions vWbp interacts with VWF and with the SrtA-dependent staphylococcal surface protein ClfA. The complex formed by VWF, secreted vWbp and bacterial ClfA anchors S. aureus to vascular endothelium under shear stress.
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Affiliation(s)
- J Claes
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
- Cardiovascular Developmental Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - L Liesenborghs
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - M Peetermans
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - T R Veloso
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
- Cardiovascular Developmental Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - D Missiakas
- Department of Microbiology, University of Chicago, Chicago, IL, USA
| | - O Schneewind
- Department of Microbiology, University of Chicago, Chicago, IL, USA
| | - S Mancini
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - J M Entenza
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - M F Hoylaerts
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - R Heying
- Cardiovascular Developmental Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - P Verhamme
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
| | - T Vanassche
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
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49
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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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50
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Thomer L, Schneewind O, Missiakas D. Pathogenesis of Staphylococcus aureus Bloodstream Infections. ANNUAL REVIEW OF PATHOLOGY 2016; 11:343-64. [PMID: 26925499 PMCID: PMC5068359 DOI: 10.1146/annurev-pathol-012615-044351] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Staphylococcus aureus, a Gram-positive bacterium colonizing nares, skin, and the gastrointestinal tract, frequently invades the skin, soft tissues, and bloodstreams of humans. Even with surgical and antibiotic therapy, bloodstream infections are associated with significant mortality. The secretion of coagulases, proteins that associate with and activate the host hemostatic factor prothrombin, and the bacterial surface display of agglutinins, proteins that bind polymerized fibrin, are key virulence strategies for the pathogenesis of S. aureus bloodstream infections, which culminate in the establishment of abscess lesions. Pathogen-controlled processes, involving a wide spectrum of secreted factors, are responsible for the recruitment and destruction of immune cells, transforming abscess lesions into purulent exudate, with which staphylococci disseminate to produce new infectious lesions or to infect new hosts. Research on S. aureus bloodstream infections is a frontier for the characterization of protective vaccine antigens and the development of immune therapeutics aiming to prevent disease or improve outcomes.
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Affiliation(s)
- Lena Thomer
- Department of Microbiology, University of Chicago, Chicago, Illinois 60637;
| | - Olaf Schneewind
- Department of Microbiology, University of Chicago, Chicago, Illinois 60637;
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