1
|
Gupta LK, Molla J, Prabhu AA. Story of Pore-Forming Proteins from Deadly Disease-Causing Agents to Modern Applications with Evolutionary Significance. Mol Biotechnol 2024; 66:1327-1356. [PMID: 37294530 DOI: 10.1007/s12033-023-00776-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 05/21/2023] [Indexed: 06/10/2023]
Abstract
Animal venoms are a complex mixture of highly specialized toxic molecules. Among them, pore-forming proteins (PFPs) or toxins (PFTs) are one of the major disease-causing toxic elements. The ability of the PFPs in defense and toxicity through pore formation on the host cell surface makes them unique among the toxin proteins. These features made them attractive for academic and research purposes for years in the areas of microbiology as well as structural biology. All the PFPs share a common mechanism of action for the attack of host cells and pore formation in which the selected pore-forming motifs of the host cell membrane-bound protein molecules drive to the lipid bilayer of the cell membrane and eventually produces water-filled pores. But surprisingly their sequence similarity is very poor. Their existence can be seen both in a soluble state and also in transmembrane complexes in the cell membrane. PFPs are prevalent toxic factors that are predominately produced by all kingdoms of life such as virulence bacteria, nematodes, fungi, protozoan parasites, frogs, plants, and also from higher organisms. Nowadays, multiple approaches to applications of PFPs have been conducted by researchers both in basic as well as applied biological research. Although PFPs are very devastating for human health nowadays researchers have been successful in making these toxic proteins into therapeutics through the preparation of immunotoxins. We have discussed the structural, and functional mechanism of action, evolutionary significance through dendrogram, domain organization, and practical applications for various approaches. This review aims to emphasize the PFTs to summarize toxic proteins together for basic knowledge as well as to highlight the current challenges, and literature gap along with the perspective of promising biotechnological applications for their future research.
Collapse
Affiliation(s)
- Laxmi Kumari Gupta
- Bioprocess Development Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal, Telangana, 506004, India
| | - Johiruddin Molla
- Ghatal Rabindra Satabarsiki Mahavidyalaya Ghatal, Paschim Medinipur, Ghatal, West Bengal, 721212, India
| | - Ashish A Prabhu
- Bioprocess Development Laboratory, Department of Biotechnology, National Institute of Technology Warangal, Warangal, Telangana, 506004, India.
| |
Collapse
|
2
|
Serra S, Iannotti V, Ferrante M, Tofiño-Vian M, Baxendale J, Silberberg G, Kohler TP, Hammerschmidt S, Ulijasz AT, Iovino F. The single D380 amino acid substitution increases pneumolysin cytotoxicity toward neuronal cells. iScience 2024; 27:109583. [PMID: 38632998 PMCID: PMC11022043 DOI: 10.1016/j.isci.2024.109583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/16/2024] [Accepted: 03/25/2024] [Indexed: 04/19/2024] Open
Abstract
Bacterial meningitis, frequently caused by Streptococcus pneumoniae (pneumococcus), represents a substantial global health threat leading to long-term neurological disorders. This study focused on the cholesterol-binding toxin pneumolysin (PLY) released by pneumococci, specifically examining clinical isolates from patients with meningitis and comparing them to the PLY-reference S. pneumoniae strain D39. Clinical isolates exhibit enhanced PLY release, likely due to a significantly higher expression of the autolysin LytA. Notably, the same single amino acid (aa) D380 substitution in the PLY D4 domain present in all clinical isolates significantly enhances cholesterol binding, pore-forming activity, and cytotoxicity toward SH-SY5Y-derived neuronal cells. Scanning electron microscopy of human neuronal cells and patch clamp electrophysiological recordings on mouse brain slices confirm the enhanced neurotoxicity of the PLY variant carrying the single aa substitution. This study highlights how a single aa modification enormously alters PLY cytotoxic potential, emphasizing the importance of PLY as a major cause of the neurological sequelae associated with pneumococcal meningitis.
Collapse
Affiliation(s)
- Simona Serra
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Vittorio Iannotti
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | | | - Joseph Baxendale
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Gilad Silberberg
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Thomas P. Kohler
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Andrew T. Ulijasz
- Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL, USA
| | - Federico Iovino
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
3
|
Lux J, Portmann H, Sánchez García L, Erhardt M, Holivololona L, Laloli L, Licheri MF, Gallay C, Hoepner R, Croucher NJ, Straume D, Veening JW, Dijkman R, Heller M, Grandgirard D, Leib SL, Hathaway LJ. Klebsiella pneumoniae peptide hijacks a Streptococcus pneumoniae permease to subvert pneumococcal growth and colonization. Commun Biol 2024; 7:425. [PMID: 38589539 PMCID: PMC11001997 DOI: 10.1038/s42003-024-06113-9] [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: 11/22/2023] [Accepted: 03/26/2024] [Indexed: 04/10/2024] Open
Abstract
Treatment of pneumococcal infections is limited by antibiotic resistance and exacerbation of disease by bacterial lysis releasing pneumolysin toxin and other inflammatory factors. We identified a previously uncharacterized peptide in the Klebsiella pneumoniae secretome, which enters Streptococcus pneumoniae via its AmiA-AliA/AliB permease. Subsequent downregulation of genes for amino acid biosynthesis and peptide uptake was associated with reduction of pneumococcal growth in defined medium and human cerebrospinal fluid, irregular cell shape, decreased chain length and decreased genetic transformation. The bacteriostatic effect was specific to S. pneumoniae and Streptococcus pseudopneumoniae with no effect on Streptococcus mitis, Haemophilus influenzae, Staphylococcus aureus or K. pneumoniae. Peptide sequence and length were crucial to growth suppression. The peptide reduced pneumococcal adherence to primary human airway epithelial cell cultures and colonization of rat nasopharynx, without toxicity. We identified a peptide with potential as a therapeutic for pneumococcal diseases suppressing growth of multiple clinical isolates, including antibiotic resistant strains, while avoiding bacterial lysis and dysbiosis.
Collapse
Affiliation(s)
- Janine Lux
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Hannah Portmann
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Lucía Sánchez García
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Maria Erhardt
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Lalaina Holivololona
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Laura Laloli
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Manon F Licheri
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Clement Gallay
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Robert Hoepner
- Department of Neurology, Bern University Hospital and University of Bern, Bern, Switzerland
| | - Nicholas J Croucher
- MRC Centre for Global Infectious Disease Analysis, Sir Michael Uren Hub, White City Campus, Imperial College London, London, UK
| | - Daniel Straume
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1430, Ås, Norway
| | - Jan-Willem Veening
- Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Ronald Dijkman
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Manfred Heller
- Proteomics and Mass Spectrometry Core Facility, Department for BioMedical Research (DBMR), University of Bern, Bern, Switzerland
| | - Denis Grandgirard
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Stephen L Leib
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Lucy J Hathaway
- Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Bern, Switzerland.
| |
Collapse
|
4
|
Alfano DN, Miller MJ, Bubeck Wardenburg J. Endothelial ADAM10 utilization defines a molecular pathway of vascular injury in mice with bacterial sepsis. J Clin Invest 2023; 133:e168450. [PMID: 37788087 PMCID: PMC10688991 DOI: 10.1172/jci168450] [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: 01/04/2023] [Accepted: 09/28/2023] [Indexed: 10/05/2023] Open
Abstract
The endothelium plays a critical role in the host response to infection and has been a focus of investigation in sepsis. While it is appreciated that intravascular thrombus formation, severe inflammation, and loss of endothelial integrity impair tissue oxygenation during sepsis, the precise molecular mechanisms that lead to endothelial injury remain poorly understood. We demonstrate here that endothelial ADAM10 was essential for the pathogenesis of Staphylococcus aureus sepsis, contributing to α-toxin-mediated (Hla-mediated) microvascular thrombus formation and lethality. As ADAM10 is essential for endothelial development and homeostasis, we examined whether other major human sepsis pathogens also rely on ADAM10-dependent pathways in pathogenesis. Mice harboring an endothelium-specific knockout of ADAM10 were protected against lethal Pseudomonas aeruginosa and Streptococcus pneumoniae sepsis, yet remained fully susceptible to group B streptococci and Candida albicans sepsis. These studies illustrate a previously unknown role for ADAM10 in sepsis-associated endothelial injury and suggest that understanding pathogen-specific divergent host pathways in sepsis may enable more precise targeting of disease.
Collapse
Affiliation(s)
| | - Mark J. Miller
- Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | | |
Collapse
|
5
|
Chen Y, Li L, Wang C, Zhang Y, Zhou Y. Necrotizing Pneumonia in Children: Early Recognition and Management. J Clin Med 2023; 12:jcm12062256. [PMID: 36983257 PMCID: PMC10051935 DOI: 10.3390/jcm12062256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/27/2023] [Accepted: 03/02/2023] [Indexed: 03/17/2023] Open
Abstract
Necrotizing pneumonia (NP) is an uncommon complicated pneumonia with an increasing incidence. Early recognition and timely management can bring excellent outcomes. The diagnosis of NP depends on chest computed tomography, which has radiation damage and may miss the optimal treatment time. The present review aimed to elaborate on the reported predictors for NP. The possible pathogenesis of Streptococcus pneumoniae, Staphylococcus aureus, Mycoplasma pneumoniae and coinfection, clinical manifestations and management were also discussed. Although there is still a long way for these predictors to be used in clinical, it is necessary to investigate early predictors for NP in children.
Collapse
Affiliation(s)
- Yuanyuan Chen
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China
- National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Lanxin Li
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China
- National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Chenlu Wang
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China
- National Clinical Research Center for Child Health, Hangzhou 310052, China
| | - Yuanyuan Zhang
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China
- National Clinical Research Center for Child Health, Hangzhou 310052, China
- Correspondence: (Y.Z.); (Y.Z.)
| | - Yunlian Zhou
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou 310052, China
- National Clinical Research Center for Child Health, Hangzhou 310052, China
- Correspondence: (Y.Z.); (Y.Z.)
| |
Collapse
|
6
|
Barichello T, Rocha Catalão CH, Rohlwink UK, van der Kuip M, Zaharie D, Solomons RS, van Toorn R, Tutu van Furth M, Hasbun R, Iovino F, Namale VS. Bacterial meningitis in Africa. Front Neurol 2023; 14:822575. [PMID: 36864913 PMCID: PMC9972001 DOI: 10.3389/fneur.2023.822575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 01/18/2023] [Indexed: 02/16/2023] Open
Abstract
Bacterial meningitis differs globally, and the incidence and case fatality rates vary by region, country, pathogen, and age group; being a life-threatening disease with a high case fatality rate and long-term complications in low-income countries. Africa has the most significant prevalence of bacterial meningitis illness, and the outbreaks typically vary with the season and the geographic location, with a high incidence in the meningitis belt of the sub-Saharan area from Senegal to Ethiopia. Streptococcus pneumoniae (pneumococcus) and Neisseria meningitidis (meningococcus) are the main etiological agents of bacterial meningitis in adults and children above the age of one. Streptococcus agalactiae (group B Streptococcus), Escherichia coli, and Staphylococcus aureus are neonatal meningitis's most common causal agents. Despite efforts to vaccinate against the most common causes of bacterial neuro-infections, bacterial meningitis remains a significant cause of mortality and morbidity in Africa, with children below 5 years bearing the heaviest disease burden. The factors attributed to this continued high disease burden include poor infrastructure, continued war, instability, and difficulty in diagnosis of bacterial neuro-infections leading to delay in treatment and hence high morbidity. Despite having the highest disease burden, there is a paucity of African data on bacterial meningitis. In this article, we discuss the common etiologies of bacterial neuroinfectious diseases, diagnosis and the interplay between microorganisms and the immune system, and the value of neuroimmune changes in diagnostics and therapeutics.
Collapse
Affiliation(s)
- Tatiana Barichello
- Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
- Faillace Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Carlos Henrique Rocha Catalão
- Faillace Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
- Department of Neuroscience and Behavioral Science, Ribeirao Preto Medical School, University of São Paulo (USP), Ribeirao Preto, SP, Brazil
| | - Ursula K. Rohlwink
- Pediatric Neurosurgery Unit, Red Cross War Memorial Children's Hospital, Cape Town, South Africa
- Division of Neurosurgery, University of Cape Town, Cape Town, South Africa
- Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Martijn van der Kuip
- Department of Pediatric Infectious Diseases and Immunology, Amsterdam Infection and Immunity Institute, Amsterdam University Medical Centers, Vrije Universiteit, Amsterdam, Netherlands
| | - Dan Zaharie
- Department of Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
- National Health Laboratory Services, Tygerberg Hospital, Cape Town, South Africa
| | - Regan S. Solomons
- Department of Pediatric and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Ronald van Toorn
- Department of Pediatric and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Marceline Tutu van Furth
- Department of Pediatric Infectious Diseases and Immunology, Amsterdam Infection and Immunity Institute, Amsterdam University Medical Centers, Vrije Universiteit, Amsterdam, Netherlands
| | - Rodrigo Hasbun
- Division of Infectious Diseases, Department of Internal Medicine, UT Health, McGovern Medical School, Houston, TX, United States
| | - Federico Iovino
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Vivian Ssonko Namale
- Columbia University Irving Medical Center and New York Presbyterian Hospital, New York, NY, United States
- Department of Paediatrics and Child Health, Makerere University College of Health Sciences, Kampala, Uganda
| |
Collapse
|
7
|
Cima Cabal MD, Molina F, López-Sánchez JI, Pérez-Santín E, Del Mar García-Suárez M. Pneumolysin as a target for new therapies against pneumococcal infections: A systematic review. PLoS One 2023; 18:e0282970. [PMID: 36947540 PMCID: PMC10032530 DOI: 10.1371/journal.pone.0282970] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 02/28/2023] [Indexed: 03/23/2023] Open
Abstract
BACKGROUND This systematic review evaluates pneumolysin (PLY) as a target for new treatments against pneumococcal infections. Pneumolysin is one of the main virulence factors produced by all types of pneumococci. This toxin (53 kDa) is a highly conserved protein that binds to cholesterol in eukaryotic cells, forming pores that lead to cell destruction. METHODS The databases consulted were MEDLINE, Web of Science, and Scopus. Articles were independently screened by title, abstract, and full text by two researchers, and using consensus to resolve any disagreements that occurred. Articles in other languages different from English, patents, cases report, notes, chapter books and reviews were excluded. Searches were restricted to the years 2000 to 2021. Methodological quality was evaluated using OHAT framework. RESULTS Forty-one articles describing the effects of different molecules that inhibit PLY were reviewed. Briefly, the inhibitory molecules found were classified into three main groups: those exerting a direct effect by binding and/or blocking PLY, those acting indirectly by preventing its effects on host cells, and those whose mechanisms are unknown. Although many molecules are proposed as toxin blockers, only some of them, such as antibiotics, peptides, sterols, and statins, have the probability of being implemented as clinical treatment. In contrast, for other molecules, there are limited studies that demonstrate efficacy in animal models with sufficient reliability. DISCUSSION Most of the studies reviewed has a good level of confidence. However, one of the limitations of this systematic review is the lack of homogeneity of the studies, what prevented to carry out a statistical comparison of the results or meta-analysis. CONCLUSION A panel of molecules blocking PLY activity are associated with the improvement of the inflammatory process triggered by the pneumococcal infection. Some molecules have already been used in humans for other purposes, so they could be safe for use in patients with pneumococcal infections. These patients might benefit from a second line treatment during the initial stages of the infection preventing acute respiratory distress syndrome and invasive pneumococcal diseases. Additional research using the presented set of compounds might further improve the clinical management of these patients.
Collapse
Affiliation(s)
- María Dolores Cima Cabal
- Escuela Superior de Ingeniería y Tecnología (ESIT), Universidad Internacional de La Rioja, UNIR, Logroño, La Rioja, Spain
| | - Felipe Molina
- Genética, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - José Ignacio López-Sánchez
- Escuela Superior de Ingeniería y Tecnología (ESIT), Universidad Internacional de La Rioja, UNIR, Logroño, La Rioja, Spain
| | - Efrén Pérez-Santín
- Escuela Superior de Ingeniería y Tecnología (ESIT), Universidad Internacional de La Rioja, UNIR, Logroño, La Rioja, Spain
| | - María Del Mar García-Suárez
- Escuela Superior de Ingeniería y Tecnología (ESIT), Universidad Internacional de La Rioja, UNIR, Logroño, La Rioja, Spain
| |
Collapse
|
8
|
The Importance of Pore-Forming Toxins in Multiple Organ Injury and Dysfunction. Biomedicines 2022; 10:biomedicines10123256. [PMID: 36552012 PMCID: PMC9776026 DOI: 10.3390/biomedicines10123256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/03/2022] [Accepted: 12/07/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Multiple organ injury and dysfunction often occurs in acute critical illness and adversely affects survival. However, in patients who survive, organ function usually recovers without permanent damage. It is, therefore, likely that there are reversible mechanisms, but this is poorly understood in the pathogenesis of multiple organ dysfunction syndrome (MODS). AIMS Based on our knowledge of extracellular histones and pneumolysin, as endogenous and exogenous pore-forming toxins, respectively, here we clarify if the extent of cell membrane disruption and recovery is important in MODS. METHODS This is a combination of retrospective clinical studies of a cohort of 98 patients from an intensive care unit (ICU) in a tertiary hospital, with interventional animal models and laboratory investigation. RESULTS In patients without septic shock and/or disseminate intravascular coagulation (DIC), circulating histones also strongly correlated with sequential organ failure assessment (SOFA) scores, suggesting their pore-forming property might play an important role. In vivo, histones or pneumolysin infusion similarly caused significant elevation of cell damage markers and multiple organ injury. In trauma and sepsis models, circulating histones strongly correlated with these markers, and anti-histone reagents significantly reduced their release. Comparison of pneumolysin deletion and its parental strain-induced sepsis mouse model showed that pneumolysin was not essential for sepsis development, but enhanced multiple organ damage and reduced survival time. In vitro, histones and pneumolysin treatment disrupt cell membrane integrity, resulting in changes in whole-cell currents and elevated intracellular Ca2+ to lead to Ca2+ overload. Cell-specific damage markers, lactate dehydrogenase (LDH), alanine aminotransferase (ALT), and cardiac troponin I (cTnI), were released from damaged cells. Once toxins were removed, cell membrane damage could be rapidly repaired and cellular function recovered. CONCLUSION This work has confirmed the importance of pore-forming toxins in the development of MODS and proposed a potential mechanism to explain the reversibility of MODS. This may form the foundation for the development of effective therapies.
Collapse
|
9
|
Involvement of Bacterial Extracellular Membrane Nanovesicles in Infectious Diseases and Their Application in Medicine. Pharmaceutics 2022; 14:pharmaceutics14122597. [PMID: 36559091 PMCID: PMC9784355 DOI: 10.3390/pharmaceutics14122597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 11/02/2022] [Accepted: 11/23/2022] [Indexed: 11/27/2022] Open
Abstract
Bacterial extracellular membrane nanovesicles (EMNs) are attracting the attention of scientists more and more every year. These formations are involved in the pathogenesis of numerous diseases, among which, of course, the leading role is occupied by infectious diseases, the causative agents of which are a range of Gram-positive and Gram-negative bacteria. A separate field for the study of the role of EMN is cancer. Extracellular membrane nanovesicles nowadays have a practical application as vaccine carriers for immunization against many infectious diseases. At present, the most essential point is their role in stimulating immune response to bacterial infections and tumor cells. The possibility of nanovesicles' practical use in several disease treatments is being evaluated. In our review, we listed diseases, focusing on their multitude and diversity, for which EMNs are essential, and also considered in detail the possibilities of using EMNs in the therapy and prevention of various pathologies.
Collapse
|
10
|
Batori RK, Chen F, Bordan Z, Haigh S, Su Y, Verin AD, Barman SA, Stepp DW, Chakraborty T, Lucas R, Fulton DJR. Protective role of Cav-1 in pneumolysin-induced endothelial barrier dysfunction. Front Immunol 2022; 13:945656. [PMID: 35967431 PMCID: PMC9363592 DOI: 10.3389/fimmu.2022.945656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/04/2022] [Indexed: 01/16/2023] Open
Abstract
Pneumolysin (PLY) is a bacterial pore forming toxin and primary virulence factor of Streptococcus pneumonia, a major cause of pneumonia. PLY binds cholesterol-rich domains of the endothelial cell (EC) plasma membrane resulting in pore assembly and increased intracellular (IC) Ca2+ levels that compromise endothelial barrier integrity. Caveolae are specialized plasmalemma microdomains of ECs enriched in cholesterol. We hypothesized that the abundance of cholesterol-rich domains in EC plasma membranes confers cellular susceptibility to PLY. Contrary to this hypothesis, we found increased PLY-induced IC Ca2+ following membrane cholesterol depletion. Caveolin-1 (Cav-1) is an essential structural protein of caveolae and its regulation by cholesterol levels suggested a possible role in EC barrier function. Indeed, Cav-1 and its scaffolding domain peptide protected the endothelial barrier from PLY-induced disruption. In loss of function experiments, Cav-1 was knocked-out using CRISPR-Cas9 or silenced in human lung microvascular ECs. Loss of Cav-1 significantly enhanced the ability of PLY to disrupt endothelial barrier integrity. Rescue experiments with re-expression of Cav-1 or its scaffolding domain peptide protected the EC barrier against PLY-induced barrier disruption. Dynamin-2 (DNM2) is known to regulate caveolar membrane endocytosis. Inhibition of endocytosis, with dynamin inhibitors or siDNM2 amplified PLY induced EC barrier dysfunction. These results suggest that Cav-1 protects the endothelial barrier against PLY by promoting endocytosis of damaged membrane, thus reducing calcium entry and PLY-dependent signaling.
Collapse
Affiliation(s)
- Robert K. Batori
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Feng Chen
- Department of Forensic Medicine, Nanjing Medical University, Nanjing, China
| | - Zsuzsanna Bordan
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Stephen Haigh
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Yunchao Su
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Alexander D. Verin
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
- Division of Critical Care and Pulmonary Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Scott A. Barman
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - David W. Stepp
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
- Department of Phyiology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Trinad Chakraborty
- Institute of Human Microbiology, Justus-Liebig University, Giessen, Germany
| | - Rudolf Lucas
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA, United States
- Division of Critical Care and Pulmonary Medicine, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - David J. R. Fulton
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, United States
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| |
Collapse
|
11
|
Magnetic Nanoclusters Increase the Sensitivity of Lateral Flow Immunoassays for Protein Detection: Application to Pneumolysin as a Biomarker for Streptococcus pneumoniae. NANOMATERIALS 2022; 12:nano12122044. [PMID: 35745381 PMCID: PMC9228753 DOI: 10.3390/nano12122044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/07/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022]
Abstract
Lateral flow immunoassays for detecting biomarkers in body fluids are simple, quick, inexpensive point-of-care tests widely used in disease surveillance, such as during the coronavirus disease 2019 (COVID-19) pandemic. Improvements in sensitivity would increase their utility in healthcare, food safety, and environmental control. Recently, biofunctional magnetic nanoclusters have been used to selectively label target proteins, which allows their detection and quantification with a magneto-inductive sensor. This type of detector is easily integrated with the lateral flow immunoassay format. Pneumolysin is a cholesterol-dependent cytolysin and one of the most important protein virulence factors of pneumonia produced by Streptococcus pneumoniae. It is recognized as an important biomarker for diagnosis in urine samples. Pneumonia is the infectious disease that causes the most deaths globally, especially among children under five years and adults over 65 years, most of them in low- and middle-income countries. There especially, a rapid diagnostic urine test for pneumococcal pneumonia with high sensitivity and specificity would be helpful in primary care. In this work, a lateral flow immunoassay with magnetic nanoclusters conjugated to anti-pneumolysin antibodies was combined with two strategies to increase the technique's performance. First, magnetic concentration of the protein before the immunoassay was followed by quantification by means of a mobile telephone camera, and the inductive sensor resulted in detection limits as low as 0.57 ng (telephone camera) and 0.24 ng (inductive sensor) of pneumolysin per milliliter. Second, magnetic relocation of the particles within the test strip after the immunoassay was completed increased the detected signal by 20%. Such results obtained with portable devices are promising when compared to non-portable conventional pneumolysin detection techniques such as enzyme-linked immunosorbent assays. The combination and optimization of these approaches would have excellent application in point-of-care biodetection to reduce antibiotic misuse, hospitalizations, and deaths from community-acquired pneumonia.
Collapse
|
12
|
Kwon K, Lee J, Lee S, Ree M, Kim H. Pneumolysin/Plasma Protein Adsorption, Bacterial Adherence, and Cell Adhesion Characteristics of a Cell-Membrane-Mimicking Polymer System. ACS APPLIED BIO MATERIALS 2022; 5:2240-2252. [PMID: 35436086 DOI: 10.1021/acsabm.2c00111] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This study delivers the first report on a cell-membrane-mimicking polymer system, poly[oxy(4-(13-cholenoatenonyl)-1,2,3-triazoyl-1-methyl)ethylene-random-oxy(4-(13-phosphorylcholinenonyl)-1,2,3-triazoyl-1-methyl)ethylene] (PGA-CholmPCn) films in various compositions in terms of physicochemical properties, protein adsorptions, bacterial adherences, and human cell adhesions. Higher Chol-containing PGA-CholmPCn in a self-assembled multi-bilayer membrane structure is confirmed to show excellently high affinity to pneumolysin (a cytolysin) and its C-terminal fragment (domain 4) but substantially suppressed affinity to the N-terminal fragment (domains 1-3) and further to plasma proteins. Furthermore, the adherences of pathogenic bacteria are increased favorably; however, the adhesion and proliferation of a human HEp-2 cell line are hindered severely. In contrast, higher-PC-containing PGA-CholmPCn membranes promote HEp-2 cell adhesion and proliferation but significantly suppress the adsorptions of pneumolysin and its fragments and plasma proteins as well as bacterial adherence. The results collectively confirm that PGA-CholmPCn can yield a membrane platform enriched with hydrophobic Chol and hydrophilic and zwitterionic PC moieties in any desired compositions, providing highly selective and sensitive physicochemical characters and biocompatibilities which are demanded for applications in various fields including biomedicine, cosmetics, and environmentally friendly consumer products.
Collapse
Affiliation(s)
- Kyungho Kwon
- Hanwha Solution/Chemical Research & Development Institute, 76 Gajeong-ro, Yuseong-gu, Daejeon 34128, Republic of Korea
| | - Jongchan Lee
- Analytical Sciences, LG Chem R&D Center, 188 Munji-ro, Yuseong-gu, Daejeon 34122, Republic of Korea
| | - Soomin Lee
- Department of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea
| | - Moonhor Ree
- Surface Technology Institute, Ceko Corporation, 519 Dunchon-daero, Jungwon-gu, Seongnam 13216, Republic of Korea
| | - Heesoo Kim
- Department of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea
| |
Collapse
|
13
|
Pereira JM, Xu S, Leong JM, Sousa S. The Yin and Yang of Pneumolysin During Pneumococcal Infection. Front Immunol 2022; 13:878244. [PMID: 35529870 PMCID: PMC9074694 DOI: 10.3389/fimmu.2022.878244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/23/2022] [Indexed: 12/15/2022] Open
Abstract
Pneumolysin (PLY) is a pore-forming toxin produced by the human pathobiont Streptococcus pneumoniae, the major cause of pneumonia worldwide. PLY, a key pneumococcal virulence factor, can form transmembrane pores in host cells, disrupting plasma membrane integrity and deregulating cellular homeostasis. At lytic concentrations, PLY causes cell death. At sub-lytic concentrations, PLY triggers host cell survival pathways that cooperate to reseal the damaged plasma membrane and restore cell homeostasis. While PLY is generally considered a pivotal factor promoting S. pneumoniae colonization and survival, it is also a powerful trigger of the innate and adaptive host immune response against bacterial infection. The dichotomy of PLY as both a key bacterial virulence factor and a trigger for host immune modulation allows the toxin to display both "Yin" and "Yang" properties during infection, promoting disease by membrane perforation and activating inflammatory pathways, while also mitigating damage by triggering host cell repair and initiating anti-inflammatory responses. Due to its cytolytic activity and diverse immunomodulatory properties, PLY is integral to every stage of S. pneumoniae pathogenesis and may tip the balance towards either the pathogen or the host depending on the context of infection.
Collapse
Affiliation(s)
- Joana M. Pereira
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Molecular and Cellular (MC) Biology PhD Program, ICBAS - Instituto de Ciência Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - Shuying Xu
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States
- Graduate Program in Immunology, Tufts Graduate School of Biomedical Sciences, Boston, MA, United States
| | - John M. Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States
| | - Sandra Sousa
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| |
Collapse
|
14
|
Kopenhagen A, Ramming I, Camp B, Hammerschmidt S, Fulde M, Müsken M, Steinert M, Bergmann S. Streptococcus pneumoniae Affects Endothelial Cell Migration in Microfluidic Circulation. Front Microbiol 2022; 13:852036. [PMID: 35401456 PMCID: PMC8990767 DOI: 10.3389/fmicb.2022.852036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 02/04/2022] [Indexed: 01/12/2023] Open
Abstract
Bloodstream infections caused by Streptococcus pneumoniae induce strong inflammatory and procoagulant cellular responses and affect the endothelial barrier of the vascular system. Bacterial virulence determinants, such as the cytotoxic pore-forming pneumolysin, increase the endothelial barrier permeability by inducing cell apoptosis and cell damage. As life-threatening consequences, disseminated intravascular coagulation followed by consumption coagulopathy and low blood pressure is described. With the aim to decipher the role of pneumolysin in endothelial damage and leakage of the vascular barrier in more detail, we established a chamber-separation cell migration assay (CSMA) used to illustrate endothelial wound healing upon bacterial infections. We used chambered inlets for cell cultivation, which, after removal, provide a cell-free area of 500 μm in diameter as a defined gap in primary endothelial cell layers. During the process of wound healing, the size of the cell-free area is decreasing due to cell migration and proliferation, which we quantitatively determined by microscopic live cell monitoring. In addition, differential immunofluorescence staining combined with confocal microscopy was used to morphologically characterize the effect of bacterial attachment on cell migration and the velocity of gap closure. In all assays, the presence of wild-type pneumococci significantly inhibited endothelial gap closure. Remarkably, even in the presence of pneumolysin-deficient pneumococci, cell migration was significantly retarded. Moreover, the inhibitory effect of pneumococci on the proportion of cell proliferation versus cell migration within the process of endothelial gap closure was assessed by implementation of a fluorescence-conjugated nucleoside analogon. We further combined the endothelial CSMA with a microfluidic pump system, which for the first time enabled the microscopic visualization and monitoring of endothelial gap closure in the presence of circulating bacteria at defined vascular shear stress values for up to 48 h. In accordance with our CSMA results under static conditions, the gap remained cell free in the presence of circulating pneumococci in flow. Hence, our combined endothelial cultivation technique represents a complex in vitro system, which mimics the vascular physiology as close as possible by providing essential parameters of the blood flow to gain new insights into the effect of pneumococcal infection on endothelial barrier integrity in flow.
Collapse
Affiliation(s)
- Anna Kopenhagen
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Isabell Ramming
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany.,Department of Infectious Diseases, Robert Koch Institute, Wernigerode, Germany
| | - Belinda Camp
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany.,Department of Pneumology, University Hospital Magdeburg, Magdeburg, Germany
| | - Sven Hammerschmidt
- Institute for Genetics and Functional Genomics, Department of Molecular Genetics and Infection Biology, Universität Greifswald, Greifswald, Germany
| | - Marcus Fulde
- Institute of Microbiology and Epizootics, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Mathias Müsken
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Michael Steinert
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany.,Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Simone Bergmann
- Institut für Mikrobiologie, Technische Universität Braunschweig, Braunschweig, Germany
| |
Collapse
|
15
|
Stevens EJ, Morse DJ, Bonini D, Duggan S, Brignoli T, Recker M, Lees JA, Croucher NJ, Bentley S, Wilson DJ, Earle SG, Dixon R, Nobbs A, Jenkinson H, van Opijnen T, Thibault D, Wilkinson OJ, Dillingham MS, Carlile S, McLoughlin RM, Massey RC. Targeted control of pneumolysin production by a mobile genetic element in Streptococcus pneumoniae. Microb Genom 2022; 8:000784. [PMID: 35416147 PMCID: PMC9453066 DOI: 10.1099/mgen.0.000784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Streptococcus pneumoniae is a major human pathogen that can cause severe invasive diseases such as pneumonia, septicaemia and meningitis. Young children are at a particularly high risk, with an estimated 3-4 million cases of severe disease and between 300 000 and 500 000 deaths attributable to pneumococcal disease each year. The haemolytic toxin pneumolysin (Ply) is a primary virulence factor for this bacterium, yet despite its key role in pathogenesis, immune evasion and transmission, the regulation of Ply production is not well defined. Using a genome-wide association approach, we identified a large number of potential affectors of Ply activity, including a gene acquired horizontally on the antibiotic resistance-conferring Integrative and Conjugative Element (ICE) ICESp23FST81. This gene encodes a novel modular protein, ZomB, which has an N-terminal UvrD-like helicase domain followed by two Cas4-like domains with potent ATP-dependent nuclease activity. We found the regulatory effect of ZomB to be specific for the ply operon, potentially mediated by its high affinity for the BOX repeats encoded therein. Using a murine model of pneumococcal colonization, we further demonstrate that a ZomB mutant strain colonizes both the upper respiratory tract and lungs at higher levels when compared to the wild-type strain. While the antibiotic resistance-conferring aspects of ICESp23FST81 are often credited with contributing to the success of the S. pneumoniae lineages that acquire it, its ability to control the expression of a major virulence factor implicated in bacterial transmission is also likely to have played an important role.
Collapse
Affiliation(s)
- Emily J Stevens
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Daniel J Morse
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Dora Bonini
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Seána Duggan
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Tarcisio Brignoli
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK
| | - Mario Recker
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Exeter, TR10 9FE, UK.,Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - John A Lees
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, St. Mary's Campus, Imperial College London, London, W2 1PG, UK
| | - Nicholas J Croucher
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, St. Mary's Campus, Imperial College London, London, W2 1PG, UK
| | - Stephen Bentley
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Daniel J Wilson
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Oxford, OX3 7LF, UK
| | - Sarah G Earle
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Oxford, OX3 7LF, UK
| | - Robert Dixon
- Big Data Institute, Nuffield Department of Population Health, University of Oxford, Oxford, OX3 7LF, UK
| | - Angela Nobbs
- Bristol Dental School, University of Bristol, Bristol, BS1 2LY, UK
| | - Howard Jenkinson
- Bristol Dental School, University of Bristol, Bristol, BS1 2LY, UK
| | | | - Derek Thibault
- Biology Department, Boston College, Chestnut Hill, MA, USA
| | - Oliver J Wilkinson
- DNA-Protein Interactions Unit, School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - Mark S Dillingham
- DNA-Protein Interactions Unit, School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
| | - Simon Carlile
- Host Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Rachel M McLoughlin
- Host Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Ruth C Massey
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, BS8 1TD, UK.,Schools of Microbiology and Medicine and APC Microbiome Ireland, University College Cork, Cork, Ireland
| |
Collapse
|
16
|
Streptococcus pneumoniae exerts oxidative stress, subverts antioxidant signaling and autophagy in human corneal epithelial cells that is alleviated by tert-Butylhydroquinone. Med Microbiol Immunol 2022; 211:119-132. [PMID: 35325292 DOI: 10.1007/s00430-022-00731-y] [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: 08/07/2021] [Accepted: 03/07/2022] [Indexed: 10/18/2022]
Abstract
Streptococcus pneumoniae is one of the leading causes of bacterial keratitis in the developing world and globally. In the current study, we have determined oxidative stress as pathogenesis of S. pneumoniae infection in corneal tissues and human corneal epithelial cells (HCEC) and explored host immune response of HCEC towards S. pneumoniae. We also determined whether treatment with tert-Butylhydroquinone (tBHQ), a Nrf2 inducer, could alleviate oxidative stress and reduce bacterial cytotoxicity in these cells. Oxidative stress was determined in corneal tissues of patients and HCEC by immunohistochemistry and immunofluorescence analysis, respectively. The expression of antioxidant genes, cytokines and antimicrobial peptides was determined by quantitative PCR. Infection of HCEC by S. pneumoniae was determined by colony-forming units. The autophagy and cell death were determined by fluorescence microscopy. The phosphorylation of signaling proteins was evaluated by immunoblot analysis. S. pneumoniae induced oxidative stress during corneal infections and inhibited antioxidant signaling pathways and immune responses like autophagy. tBHQ aided in restoring Nrf2 activation, reduced reactive oxygen species generation and prevented cytotoxicity and cell death in S. pneumoniae-infected HCEC. tBHQ also induced autophagy in a Nrf2-dependent manner and reduced bacterial survival in HCEC. Increased expression of antimicrobial peptides by tBHQ might have contributed to a reduction of bacterial load and cytotoxicity, as exemplified in LL-37 depleted corneal epithelial cells exposed to S. pneumoniae compared to control siRNA-transfected cells. tBHQ mediates alleviation of oxidative stress induced by S. pneumoniae by activating Nrf2-mediated antioxidant signaling in corneal epithelial cells. tBHQ also enhances expression of antimicrobial peptides in corneal cells and aids in inhibition of bacterial survival and cytotoxicity of HCEC.
Collapse
|
17
|
Paulikat AD, Tölken LA, Jachmann LH, Burchhardt G, Hammerschmidt S, Siemens N. <b><i>Streptococcus pneumoniae</i></b> Impairs Maturation of Human Dendritic Cells and Consequent Activation of CD4<sup>+</sup> T Cells via Pneumolysin. J Innate Immun 2022; 14:569-580. [PMID: 35249041 PMCID: PMC9485967 DOI: 10.1159/000522339] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/25/2022] [Indexed: 01/11/2023] Open
Abstract
Influenza A Virus (IAV), Staphylococcus aureus (staphylococci), and Streptococcus pneumoniae (pneumococci) are leading viral and bacterial causes of pneumonia. Dendritic cells (DCs) are present in the lower respiratory tract. They are characterized by low expression of co-stimulatory molecules, including CD80 and CD86 and high capacity of antigen uptake. Subsequently, DCs upregulate co-stimulatory signals and cytokine secretion to effectively induce T-cell priming. Here, we investigated these processes in response to bacterial and viral single as well as coinfections using human monocyte-derived (mo)DCs. Irrespective of single or coinfections, moDCs matured in response to IAV and/or staphylococcal infections, secreted a wide range of cytokines, and activated CD4<sup>+</sup>, CD8<sup>+</sup> as well as double-negative T cells. In contrast, pneumococcal single and coinfections impaired moDC maturation, which was characterized by low expression of CD80 and CD86, downregulated expression of CD40, and a mild cytokine release resulting in abrogated CD4<sup>+</sup> T-cell activation. These actions were attributed to the cholesterol-dependent cytotoxin pneumolysin (Ply). Infections with a ply-deficient mutant resulted in restored moDC maturation and exclusive CD4<sup>+</sup> T-cell activation. These findings show that Ply has important immunomodulatory functions, supporting further investigations in specific modalities of Ply-DC interplay.
Collapse
|
18
|
Lane JR, Tata M, Briles DE, Orihuela CJ. A Jack of All Trades: The Role of Pneumococcal Surface Protein A in the Pathogenesis of Streptococcus pneumoniae. Front Cell Infect Microbiol 2022; 12:826264. [PMID: 35186799 PMCID: PMC8847780 DOI: 10.3389/fcimb.2022.826264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/10/2022] [Indexed: 12/11/2022] Open
Abstract
Streptococcus pneumoniae (Spn), or the pneumococcus, is a Gram-positive bacterium that colonizes the upper airway. Spn is an opportunistic pathogen capable of life-threatening disease should it become established in the lungs, gain access to the bloodstream, or disseminate to vital organs including the central nervous system. Spn is encapsulated, allowing it to avoid phagocytosis, and current preventative measures against infection include polyvalent vaccines composed of capsular polysaccharide corresponding to its most prevalent serotypes. The pneumococcus also has a plethora of surface components that allow the bacteria to adhere to host cells, facilitate the evasion of the immune system, and obtain vital nutrients; one family of these are the choline-binding proteins (CBPs). Pneumococcal surface protein A (PspA) is one of the most abundant CBPs and confers protection against the host by inhibiting recognition by C-reactive protein and neutralizing the antimicrobial peptide lactoferricin. Recently our group has identified two new roles for PspA: binding to dying host cells via host-cell bound glyceraldehyde 3-phosphate dehydrogenase and co-opting of host lactate dehydrogenase to enhance lactate availability. These properties have been shown to influence Spn localization and enhance virulence in the lower airway, respectively. Herein, we review the impact of CBPs, and in particular PspA, on pneumococcal pathogenesis. We discuss the potential and limitations of using PspA as a conserved vaccine antigen in a conjugate vaccine formulation. PspA is a vital component of the pneumococcal virulence arsenal - therefore, understanding the molecular aspects of this protein is essential in understanding pneumococcal pathogenesis and utilizing PspA as a target for treating or preventing pneumococcal pneumonia.
Collapse
Affiliation(s)
| | | | | | - Carlos J. Orihuela
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, United States
| |
Collapse
|
19
|
Intracellularly Released Cholesterol from Polymer-Based Delivery Systems Alters Cellular Responses to Pneumolysin and Promotes Cell Survival. Metabolites 2021; 11:metabo11120821. [PMID: 34940579 PMCID: PMC8709088 DOI: 10.3390/metabo11120821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 11/30/2022] Open
Abstract
Cholesterol is highly abundant within all human body cells and modulates critical cellular functions related to cellular plasticity, metabolism, and survival. The cholesterol-binding toxin pneumolysin represents an essential virulence factor of Streptococcus pneumoniae in establishing pneumonia and other pneumococcal infections. Thus, cholesterol scavenging of pneumolysin is a promising strategy to reduce S. pneumoniae induced lung damage. There may also be a second cholesterol-dependent mechanism whereby pneumococcal infection and the presence of pneumolysin increase hepatic sterol biosynthesis. Here we investigated a library of polymer particles varying in size and composition that allow for the cellular delivery of cholesterol and their effects on cell survival mechanisms following pneumolysin exposure. Intracellular delivery of cholesterol by nanocarriers composed of Eudragit E100–PLGA rescued pneumolysin-induced alterations of lipid homeostasis and enhanced cell survival irrespective of neutralization of pneumolysin.
Collapse
|
20
|
Green AE, Howarth D, Chaguza C, Echlin H, Langendonk RF, Munro C, Barton TE, Hinton JCD, Bentley SD, Rosch JW, Neill DR. Pneumococcal Colonization and Virulence Factors Identified Via Experimental Evolution in Infection Models. Mol Biol Evol 2021; 38:2209-2226. [PMID: 33502519 PMCID: PMC8136498 DOI: 10.1093/molbev/msab018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Streptococcus pneumoniae is a commensal of the human nasopharynx and a major cause of respiratory and invasive disease. We examined adaptation and evolution of pneumococcus, within nasopharynx and lungs, in an experimental system where the selective pressures associated with transmission were removed. This was achieved by serial passage of pneumococci, separately, in mouse models of nasopharyngeal carriage or pneumonia. Passaged pneumococci became more effective colonizers of the respiratory tract and we observed several examples of potential parallel evolution. The cell wall-modifying glycosyltransferase LafA was under strong selection during lung passage, whereas the surface expressed pneumococcal vaccine antigen gene pvaA and the glycerol-3-phosphate dehydrogenase gene gpsA were frequent targets of mutation in nasopharynx-passaged pneumococci. These mutations were not identified in pneumococci that were separately evolved by serial passage on laboratory agar. We focused on gpsA, in which the same single nucleotide polymorphism arose in two independently evolved nasopharynx-passaged lineages. We describe a new role for this gene in nasopharyngeal carriage and show that the identified single nucleotide change confers resistance to oxidative stress and enhanced nasopharyngeal colonization potential. We demonstrate that polymorphisms in gpsA arise and are retained during human colonization. These findings highlight how within-host environmental conditions can determine trajectories of bacterial evolution. Relative invasiveness or attack rate of pneumococcal lineages may be defined by genes that make niche-specific contributions to bacterial fitness. Experimental evolution in animal infection models is a powerful tool to investigate the relative roles played by pathogen virulence and colonization factors within different host niches.
Collapse
Affiliation(s)
- Angharad E Green
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Deborah Howarth
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Chrispin Chaguza
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
| | - Haley Echlin
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - R Frèdi Langendonk
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Connor Munro
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Thomas E Barton
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Jay C D Hinton
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Stephen D Bentley
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, United Kingdom
| | - Jason W Rosch
- Department of Infectious Disease, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Daniel R Neill
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| |
Collapse
|
21
|
Pospiech M, Owens SE, Miller DJ, Austin-Muttitt K, Mullins JGL, Cronin JG, Allemann RK, Sheldon IM. Bisphosphonate inhibitors of squalene synthase protect cells against cholesterol-dependent cytolysins. FASEB J 2021; 35:e21640. [PMID: 33991130 DOI: 10.1096/fj.202100164r] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 04/09/2021] [Accepted: 04/19/2021] [Indexed: 01/29/2023]
Abstract
Certain species of pathogenic bacteria damage tissues by secreting cholesterol-dependent cytolysins, which form pores in the plasma membranes of animal cells. However, reducing cholesterol protects cells against these cytolysins. As the first committed step of cholesterol biosynthesis is catalyzed by squalene synthase, we explored whether inhibiting this enzyme protected cells against cholesterol-dependent cytolysins. We first synthesized 22 different nitrogen-containing bisphosphonate molecules that were designed to inhibit squalene synthase. Squalene synthase inhibition was quantified using a cell-free enzyme assay, and validated by computer modeling of bisphosphonate molecules binding to squalene synthase. The bisphosphonates were then screened for their ability to protect HeLa cells against the damage caused by the cholesterol-dependent cytolysin, pyolysin. The most effective bisphosphonate reduced pyolysin-induced leakage of lactate dehydrogenase into cell supernatants by >80%, and reduced pyolysin-induced cytolysis from >75% to <25%. In addition, this bisphosphonate reduced pyolysin-induced leakage of potassium from cells, limited changes in the cytoskeleton, prevented mitogen-activated protein kinases cell stress responses, and reduced cellular cholesterol. The bisphosphonate also protected cells against another cholesterol-dependent cytolysin, streptolysin O, and protected lung epithelial cells and primary dermal fibroblasts against cytolysis. Our findings imply that treatment with bisphosphonates that inhibit squalene synthase might help protect tissues against pathogenic bacteria that secrete cholesterol-dependent cytolysins.
Collapse
Affiliation(s)
- Mateusz Pospiech
- Swansea University Medical School, Swansea University, Swansea, UK
| | - Siân E Owens
- Swansea University Medical School, Swansea University, Swansea, UK
| | | | | | | | - James G Cronin
- Swansea University Medical School, Swansea University, Swansea, UK
| | | | - I Martin Sheldon
- Swansea University Medical School, Swansea University, Swansea, UK
| |
Collapse
|
22
|
Kamruzzaman M, Wu AY, Iredell JR. Biological Functions of Type II Toxin-Antitoxin Systems in Bacteria. Microorganisms 2021; 9:microorganisms9061276. [PMID: 34208120 PMCID: PMC8230891 DOI: 10.3390/microorganisms9061276] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 12/14/2022] Open
Abstract
After the first discovery in the 1980s in F-plasmids as a plasmid maintenance system, a myriad of toxin-antitoxin (TA) systems has been identified in bacterial chromosomes and mobile genetic elements (MGEs), including plasmids and bacteriophages. TA systems are small genetic modules that encode a toxin and its antidote and can be divided into seven types based on the nature of the antitoxin molecules and their mechanism of action to neutralise toxins. Among them, type II TA systems are widely distributed in chromosomes and plasmids and the best studied so far. Maintaining genetic material may be the major function of type II TA systems associated with MGEs, but the chromosomal TA systems contribute largely to functions associated with bacterial physiology, including the management of different stresses, virulence and pathogenesis. Due to growing interest in TA research, extensive work has been conducted in recent decades to better understand the physiological roles of these chromosomally encoded modules. However, there are still controversies about some of the functions associated with different TA systems. This review will discuss the most current findings and the bona fide functions of bacterial type II TA systems.
Collapse
Affiliation(s)
- Muhammad Kamruzzaman
- Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia;
- Correspondence: (M.K.); (J.R.I.)
| | - Alma Y. Wu
- Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia;
| | - Jonathan R. Iredell
- Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, The University of Sydney, Westmead, NSW 2145, Australia;
- Westmead Hospital, Westmead, NSW 2145, Australia
- Correspondence: (M.K.); (J.R.I.)
| |
Collapse
|
23
|
Abstract
Childhood pneumococcal infection is a growing concern among paediatricians especially, in countries where there is no routine vaccination program against Streptococcal pneumoniae. The disease is associated with significant morbidity and mortality in young children particularly those who are under the age of two years. Its main virulent factors include polysaccharide capsule, autolysin, pneumolysin, choline-binding Protein A, the higher chance for genetic transformation, and the presence of pilli that facilitate enhanced binding of bacteria to host cellular surfaces. More severe and invasive pneumococcal infections are seen in children with immunodeficiencies, hypofunctional spleen, malnutrition, chronic lung disease and nephrotic syndrome. The disease spectrum includes a range of manifestations from trivial upper respiratory tract infections to severe invasive pneumococcal disease (PD). The basis of diagnosis is the isolation of bacteria in the culture of body fluids including blood. Antibiotics are best guided by sensitivity patterns and the emergence of resistance is a growing concern.
Collapse
|
24
|
Tabusi M, Thorsdottir S, Lysandrou M, Narciso AR, Minoia M, Srambickal CV, Widengren J, Henriques-Normark B, Iovino F. Neuronal death in pneumococcal meningitis is triggered by pneumolysin and RrgA interactions with β-actin. PLoS Pathog 2021; 17:e1009432. [PMID: 33760879 PMCID: PMC7990213 DOI: 10.1371/journal.ppat.1009432] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 02/28/2021] [Indexed: 12/14/2022] Open
Abstract
Neuronal damage is a major consequence of bacterial meningitis, but little is known about mechanisms of bacterial interaction with neurons leading to neuronal cell death. Streptococcus pneumoniae (pneumococcus) is a leading cause of bacterial meningitis and many survivors develop neurological sequelae after the acute infection has resolved, possibly due to neuronal damage. Here, we studied mechanisms for pneumococcal interactions with neurons. Using human primary neurons, pull-down experiments and mass spectrometry, we show that pneumococci interact with the cytoskeleton protein β-actin through the pilus-1 adhesin RrgA and the cytotoxin pneumolysin (Ply), thereby promoting adhesion and invasion of neurons, and neuronal death. Using our bacteremia-derived meningitis mouse model, we observe that RrgA- and Ply-expressing pneumococci co-localize with neuronal β-actin. Using purified proteins, we show that Ply, through its cholesterol-binding domain 4, interacts with the neuronal plasma membrane, thereby increasing the exposure on the outer surface of β-actin filaments, leading to more β-actin binding sites available for RrgA binding, and thus enhanced pneumococcal interactions with neurons. Pneumococcal infection promotes neuronal death possibly due to increased intracellular Ca2+ levels depending on presence of Ply, as well as on actin cytoskeleton disassembly. STED super-resolution microscopy showed disruption of β-actin filaments in neurons infected with pneumococci expressing RrgA and Ply. Finally, neuronal death caused by pneumococcal infection could be inhibited using antibodies against β-actin. The generated data potentially helps explaining mechanisms for why pneumococci frequently cause neurological sequelae.
Collapse
Affiliation(s)
- Mahebali Tabusi
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, BioClinicum J7:20, Stockholm, Sweden
- Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - Sigrun Thorsdottir
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, BioClinicum J7:20, Stockholm, Sweden
- Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - Maria Lysandrou
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, BioClinicum J7:20, Stockholm, Sweden
- Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - Ana Rita Narciso
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, BioClinicum J7:20, Stockholm, Sweden
- Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - Melania Minoia
- Department of Molecular Biosciences, The Wenner-Gren Institutet, Stockholm University, Stockholm, Sweden
| | | | - Jerker Widengren
- Department of Applied Physics, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Birgitta Henriques-Normark
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, BioClinicum J7:20, Stockholm, Sweden
- Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
| | - Federico Iovino
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, BioClinicum J7:20, Stockholm, Sweden
- Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden
- * E-mail:
| |
Collapse
|
25
|
Streptococcus pneumoniae and Its Virulence Factors H 2O 2 and Pneumolysin Are Potent Mediators of the Acute Chest Syndrome in Sickle Cell Disease. Toxins (Basel) 2021; 13:toxins13020157. [PMID: 33671422 PMCID: PMC7922783 DOI: 10.3390/toxins13020157] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 01/27/2023] Open
Abstract
Sickle cell disease (SCD) is one of the most common autosomal recessive disorders in the world. Due to functional asplenia, a dysfunctional antibody response, antibiotic drug resistance and poor response to immunization, SCD patients have impaired immunity. A leading cause of hospitalization and death in SCD patients is the acute chest syndrome (ACS). This complication is especially manifested upon infection of SCD patients with Streptococcus pneumoniae (Spn)—a facultative anaerobic Gram-positive bacterium that causes lower respiratory tract infections. Spn has developed increased rates of antibiotics resistance and is particularly virulent in SCD patients. The primary defense against Spn is the generation of reactive oxygen species (ROS) during the oxidative burst of neutrophils and macrophages. Paradoxically, Spn itself produces high levels of the ROS hydrogen peroxide (H2O2) as a virulence strategy. Apart from H2O2, Spn also secretes another virulence factor, i.e., the pore-forming exotoxin pneumolysin (PLY), a potent mediator of lung injury in patients with pneumonia in general and particularly in those with SCD. PLY is released early on in infection either by autolysis or bacterial lysis following the treatment with antibiotics and has a broad range of biological activities. This review will discuss recent findings on the role of pneumococci in ACS pathogenesis and on strategies to counteract the devastating effects of its virulence factors on the lungs in SCD patients.
Collapse
|
26
|
Bayly-Jones C, Pang SS, Spicer BA, Whisstock JC, Dunstone MA. Ancient but Not Forgotten: New Insights Into MPEG1, a Macrophage Perforin-Like Immune Effector. Front Immunol 2020; 11:581906. [PMID: 33178209 PMCID: PMC7593815 DOI: 10.3389/fimmu.2020.581906] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 09/25/2020] [Indexed: 12/29/2022] Open
Abstract
Macrophage-expressed gene 1 [MPEG1/Perforin-2 (PRF2)] is an ancient metazoan protein belonging to the Membrane Attack Complex/Perforin (MACPF) branch of the MACPF/Cholesterol Dependent Cytolysin (CDC) superfamily of pore-forming proteins (PFPs). MACPF/CDC proteins are a large and extremely diverse superfamily that forms large transmembrane aqueous channels in target membranes. In humans, MACPFs have known roles in immunity and development. Like perforin (PRF) and the membrane attack complex (MAC), MPEG1 is also postulated to perform a role in immunity. Indeed, bioinformatic studies suggest that gene duplications of MPEG1 likely gave rise to PRF and MAC components. Studies reveal partial or complete loss of MPEG1 causes an increased susceptibility to microbial infection in both cells and animals. To this end, MPEG1 expression is upregulated in response to proinflammatory signals such as tumor necrosis factor α (TNFα) and lipopolysaccharides (LPS). Furthermore, germline mutations in MPEG1 have been identified in connection with recurrent pulmonary mycobacterial infections in humans. Structural studies on MPEG1 revealed that it can form oligomeric pre-pores and pores. Strikingly, the unusual domain arrangement within the MPEG1 architecture suggests a novel mechanism of pore formation that may have evolved to guard against unwanted lysis of the host cell. Collectively, the available data suggest that MPEG1 likely functions as an intracellular pore-forming immune effector. Herein, we review the current understanding of MPEG1 evolution, regulation, and function. Furthermore, recent structural studies of MPEG1 are discussed, including the proposed mechanisms of action for MPEG1 bactericidal activity. Lastly limitations, outstanding questions, and implications of MPEG1 models are explored in the context of the broader literature and in light of newly available structural data.
Collapse
Affiliation(s)
- Charles Bayly-Jones
- ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia.,Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Siew Siew Pang
- ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia.,Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Bradley A Spicer
- ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia.,Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - James C Whisstock
- ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia.,Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia.,John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Michelle A Dunstone
- ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Melbourne, VIC, Australia.,Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| |
Collapse
|
27
|
Shoji K, Kawano R, White RJ. Analysis of Membrane Protein Deinsertion-Associated Currents with Nanoneedle-Supported Bilayers to Discover Pore Formation Mechanisms. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:10012-10021. [PMID: 32787048 DOI: 10.1021/acs.langmuir.0c00833] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Analysis of the pore formation mechanisms of biological nanopores can provide insight into pore-forming peptide-induced diseases and into the characterization of nanopores employed in sensing methods. Evaluation of pore formation mechanisms is typically performed using microscopy including atomic force microscopy, transmission electron microscopy, as well as electrically via channel current measurements using a patch-clamp amplifier. However, due to the relatively low temporal resolution of the above-mentioned microscopy techniques and the low analysis accuracy of the channel current measurements, new analytical methods are required. Here, we describe a new analytical strategy to measure and analyze both ionic currents associated with biological nanopore insertion and deinsertion into and out of lipid bilayers to determine pore formation mechanisms for several representative proteins. The current changes associated with protein deinsertion are monitored as the lipid membrane leaflets are pulled apart-a unique phenomenon enabled by our gold nanoneedle measurement probe. This deinsertion current analysis (DiCA) is performed using a gold nanoneedle-supported lipid bilayer at which a bilayer membrane is formed by bringing together two lipid monolayers on the surface of the nanoneedle and at the interface of an aqueous solution and a lipid/oil mixture. The lipid bilayer can be pulled apart by removing the nanoneedle from this interface. In this study, we demonstrate the determination of pore formation mechanisms for four different pore-forming proteins and peptides-α-hemolysin, streptolysin O, alamethicin, and amyloid β 1-42 using DiCA. As a result, we successfully discern the pore formation mechanism, either addition or expansion, for each protein/peptide by analyzing the ratio and magnitude of insertion and deinsertion current events.
Collapse
Affiliation(s)
- Kan Shoji
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
- Department of Mechanical Engineering, Nagaoka University of Technology, Nagaoka, Niigata 840-2188, Japan
| | - Ryuji Kawano
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | | |
Collapse
|
28
|
Thanawastien A, Joyce KE, Cartee RT, Haines LA, Pelton SI, Tweten RK, Killeen KP. Preclinical in vitro and in vivo profile of a highly-attenuated, broadly efficacious pneumolysin genetic toxoid. Vaccine 2020; 39:1652-1660. [PMID: 32532546 PMCID: PMC8237519 DOI: 10.1016/j.vaccine.2020.04.064] [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: 10/08/2019] [Revised: 04/03/2020] [Accepted: 04/26/2020] [Indexed: 02/05/2023]
Abstract
Pneumolysin is a highly conserved, cholesterol-dependent cytolysin that is an important Streptococcus pneumoniae virulence factor and an attractive target for vaccine development. To attenuate pneumolysin toxicity, a genetic toxoid was constructed with two amino acid changes, G293S and L460D, termed PLY-D, that reduced cytolytic activity > 125,000-fold. In mice, PLY-D elicited high anti-PLY IgG antibody titers that neutralized the cytolytic activity of the wild-type toxin in vitro. To evaluate the protective efficacy of PLY-D, mice were immunized intramuscularly and then challenged intranasally with a lethal dose of 28 clinical isolates of S. pneumoniae originating from different geographical locations, disease states (i.e. bacteremia, pneumonia), or body sites (i.e. sputum, blood). PLY-D immunization conferred significant protection from challenge with 17 of 20 serotypes (85%) and 22 of 28 strains (79%). Further, we demonstrated that immunization with PLY-D provided statistically significant improvement in survival against challenge with serotype 4 and 18C strains compared to mice immunized with a pneumococcal conjugate vaccine Prevnar 13® (PCV13). Co-administration of PLY-D and PCV13 conferred greater protection against challenge with a serotype 6B strain than immunization with either vaccine alone. These data indicate that PLY-D is a broadly protective antigen with the potential to serve as a serotype-independent vaccine against invasive pneumococcal disease either alone or in combination with PCVs.
Collapse
Affiliation(s)
- Ann Thanawastien
- Matrivax Research & Development Corporation, Boston, MA, United States
| | - Kelsey E Joyce
- Matrivax Research & Development Corporation, Boston, MA, United States
| | - Robert T Cartee
- Matrivax Research & Development Corporation, Boston, MA, United States
| | - Laurel A Haines
- Matrivax Research & Development Corporation, Boston, MA, United States
| | - Stephen I Pelton
- Boston University Schools of Medicine and Public Health, Boston Medical Center, Boston, MA, United States
| | - Rodney K Tweten
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, United States
| | - Kevin P Killeen
- Matrivax Research & Development Corporation, Boston, MA, United States.
| |
Collapse
|
29
|
Iwahashi J, Kamei K, Watanabe H. Disruption of Aspergillus fumigatus biofilm by Streptococcus pneumoniae: Mycelial fragmentation by hydrogen peroxide. J Infect Chemother 2020; 26:831-837. [PMID: 32414689 DOI: 10.1016/j.jiac.2020.03.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/07/2020] [Accepted: 03/24/2020] [Indexed: 01/06/2023]
Abstract
Biofilm is a complex structure consisting of microorganisms such as bacteria, fungi and an extracellular matrix (ECM). Biofilms are involved in most microbial infections and show persistent resistance to antibiotic treatment and immune response. Both Aspergillus fumigatus and Streptococcus pneumoniae are colonizers that can form biofilms in the respiratory tract. These pathogens have been simultaneously isolated from the same patient, but their interaction is poorly understood. We observed morphological changes in single- and mixed-species biofilms prepared for confocal laser scanning microscopy and scanning electron microscopy (SEM). Pneumococci suppressed the development of a fungal biofilm, and it even disrupted a preformed fungal biofilm. When a preformed fungal biofilm was treated with pneumococci, the mycelial network was fragmented, and only bacteria could develop. SEM revealed that the fragmented mycelium was further disrupted into fine filaments as treatment time progressed, and that the ECM of the preformed fungal biofilm had disappeared. The pneumococcal culture supernatant contained mycelial fragmentation activity that was heat-sensitive. The culture supernatant of a mutant pneumococcal strain deficient in pneumolysin (Δply) also exhibited the mycelial fragmentation activity. Enolase and lactate oxidase, which are involved in glycolysis and hydrogen peroxide production, were identified in the culture supernatant of the Δply mutant. Neither the wild type nor the mutant strain could fragment the mycelium in the presence of catalase. These data suggest that hydrogen peroxide could fragment the mycelium and would terminate the co-existence of A. fumigatus and S. pneumoniae in biofilm.
Collapse
Affiliation(s)
- Jun Iwahashi
- Department of Infection Control and Prevention, Kurume University School of Medicine, 67 Asahi-machi, Kurume City, Fukuoka 830-0011, Japan.
| | - Katsuhiko Kamei
- Division of Clinical Research, Medical Mycology Research Center, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba 260-8673, Japan
| | - Hiroshi Watanabe
- Department of Infection Control and Prevention, Kurume University School of Medicine, 67 Asahi-machi, Kurume City, Fukuoka 830-0011, Japan
| |
Collapse
|
30
|
Truncated Pneumolysin from Streptococcus pneumoniae as a TLR4-Antagonizing New Drug for Chronic Inflammatory Conditions. Cells 2020; 9:cells9051183. [PMID: 32397494 PMCID: PMC7290803 DOI: 10.3390/cells9051183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/05/2020] [Accepted: 05/07/2020] [Indexed: 11/17/2022] Open
Abstract
Microbial proteins have recently been found to have more benefits in clinical disease treatment because of their better-developed strategy and properties than traditional medicine. In this study, we investigated the effectiveness of a truncated peptide synthesized from the C-terminal sequence of pneumolysin, i.e., C70PLY4, in Streptococcus pneumoniae, in treating chronic inflammatory conditions. It has been shown that C70PLY4 significantly blocks the transendothelial migration of neutrophils and attenuates the formation of atherosclerotic plaque and the secretion of soluble forms of the intercellular adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule 1 (VCAM-1), and E-selectin in high-fat-diet/streptozotocin-induced inflammatory rats. The mechanism and the docking simulation analysis further indicated that C70PLY4 might serve as a Toll-like receptor 4 (TLR4) antagonist by competing for the binding site of MD2, an indispensable protein for lipopolysaccharide (LPS)–TLR4 interaction signaling, on the TLR4 structure. Moreover, compared to the full-length PLY, C70PLY4 seems to have no cytotoxicity in human vascular endothelial cells. Our study elucidated a possible therapeutic efficacy of C70PLY4 in reducing chronic inflammatory conditions and clarified the underlying mechanism. Thus, our findings identify a new drug candidate that, by blocking TLR4 activity, could be an effective treatment for patients with chronic inflammatory diseases.
Collapse
|
31
|
Wagner A, Weinberger B. Vaccines to Prevent Infectious Diseases in the Older Population: Immunological Challenges and Future Perspectives. Front Immunol 2020; 11:717. [PMID: 32391017 PMCID: PMC7190794 DOI: 10.3389/fimmu.2020.00717] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 03/30/2020] [Indexed: 12/15/2022] Open
Abstract
Infectious diseases are a major cause for morbidity and mortality in the older population. Demographic changes will lead to increasing numbers of older persons over the next decades. Prevention of infections becomes increasingly important to ensure healthy aging for the individual, and to alleviate the socio-economic burden for societies. Undoubtedly, vaccines are the most efficient health care measure to prevent infections. Age-associated changes of the immune system are responsible for decreased immunogenicity and clinical efficacy of most currently used vaccines in older age. Efficacy of standard influenza vaccines is only 30-50% in the older population. Several approaches, such as higher antigen dose, use of MF59 as adjuvant and intradermal administration have been implemented in order to specifically target the aged immune system. The use of a 23-valent polysaccharide vaccine against Streptococcus pneumoniae has been amended by a 13-valent conjugated pneumococcal vaccine originally developed for young children several years ago to overcome at least some of the limitations of the T cell-independent polysaccharide antigens, but still is only approximately 50% protective against pneumonia. A live-attenuated vaccine against herpes zoster, which has been available for several years, demonstrated efficacy of 51% against herpes zoster and 67% against post-herpetic neuralgia. Protection was lower in the very old and decreased several years after vaccination. Recently, a recombinant vaccine containing the viral glycoprotein gE and the novel adjuvant AS01B has been licensed. Phase III studies demonstrated efficacy against herpes zoster of approx. 90% even in the oldest age groups after administration of two doses and many countries now recommend the preferential use of this vaccine. There are still many infectious diseases causing substantial morbidity in the older population, for which no vaccines are available so far. Extensive research is ongoing to develop vaccines against novel targets with several vaccine candidates already being clinically tested, which have the potential to substantially reduce health care costs and to save many lives. In addition to the development of novel and improved vaccines, which specifically target the aged immune system, it is also important to improve uptake of the existing vaccines in order to protect the vulnerable, older population.
Collapse
Affiliation(s)
- Angelika Wagner
- Department of Pathophysiology, Infectiology, and Immunology, Institute of Specific Prophylaxis and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Birgit Weinberger
- Institute for Biomedical Aging Research, Universität Innsbruck, Innsbruck, Austria
| |
Collapse
|
32
|
Lucas R, Hadizamani Y, Gonzales J, Gorshkov B, Bodmer T, Berthiaume Y, Moehrlen U, Lode H, Huwer H, Hudel M, Mraheil MA, Toque HAF, Chakraborty T, Hamacher J. Impact of Bacterial Toxins in the Lungs. Toxins (Basel) 2020; 12:toxins12040223. [PMID: 32252376 PMCID: PMC7232160 DOI: 10.3390/toxins12040223] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/30/2020] [Accepted: 03/31/2020] [Indexed: 12/13/2022] Open
Abstract
Bacterial toxins play a key role in the pathogenesis of lung disease. Based on their structural and functional properties, they employ various strategies to modulate lung barrier function and to impair host defense in order to promote infection. Although in general, these toxins target common cellular signaling pathways and host compartments, toxin- and cell-specific effects have also been reported. Toxins can affect resident pulmonary cells involved in alveolar fluid clearance (AFC) and barrier function through impairing vectorial Na+ transport and through cytoskeletal collapse, as such, destroying cell-cell adhesions. The resulting loss of alveolar-capillary barrier integrity and fluid clearance capacity will induce capillary leak and foster edema formation, which will in turn impair gas exchange and endanger the survival of the host. Toxins modulate or neutralize protective host cell mechanisms of both the innate and adaptive immunity response during chronic infection. In particular, toxins can either recruit or kill central players of the lung's innate immune responses to pathogenic attacks, i.e., alveolar macrophages (AMs) and neutrophils. Pulmonary disorders resulting from these toxin actions include, e.g., acute lung injury (ALI), the acute respiratory syndrome (ARDS), and severe pneumonia. When acute infection converts to persistence, i.e., colonization and chronic infection, lung diseases, such as bronchitis, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) can arise. The aim of this review is to discuss the impact of bacterial toxins in the lungs and the resulting outcomes for pathogenesis, their roles in promoting bacterial dissemination, and bacterial survival in disease progression.
Collapse
Affiliation(s)
- Rudolf Lucas
- Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Department of Medicine and Division of Pulmonary Critical Care Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Correspondence: (R.L.); (J.H.); Tel.: +41-31-300-35-00 (J.H.)
| | - Yalda Hadizamani
- Lungen-und Atmungsstiftung, Bern, 3012 Bern, Switzerland;
- Pneumology, Clinic for General Internal Medicine, Lindenhofspital Bern, 3012 Bern, Switzerland
| | - Joyce Gonzales
- Department of Medicine and Division of Pulmonary Critical Care Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
| | - Boris Gorshkov
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
| | - Thomas Bodmer
- Labormedizinisches Zentrum Dr. Risch, Waldeggstr. 37 CH-3097 Liebefeld, Switzerland;
| | - Yves Berthiaume
- Department of Medicine, Faculty of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada;
| | - Ueli Moehrlen
- Pediatric Surgery, University Children’s Hospital, Zürich, Steinwiesstrasse 75, CH-8032 Zürch, Switzerland;
| | - Hartmut Lode
- Insitut für klinische Pharmakologie, Charité, Universitätsklinikum Berlin, Reichsstrasse 2, D-14052 Berlin, Germany;
| | - Hanno Huwer
- Department of Cardiothoracic Surgery, Voelklingen Heart Center, 66333 Voelklingen/Saar, Germany;
| | - Martina Hudel
- Justus-Liebig-University, Biomedical Research Centre Seltersberg, Schubertstr. 81, 35392 Giessen, Germany; (M.H.); (M.A.M.); (T.C.)
| | - Mobarak Abu Mraheil
- Justus-Liebig-University, Biomedical Research Centre Seltersberg, Schubertstr. 81, 35392 Giessen, Germany; (M.H.); (M.A.M.); (T.C.)
| | - Haroldo Alfredo Flores Toque
- Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
| | - Trinad Chakraborty
- Justus-Liebig-University, Biomedical Research Centre Seltersberg, Schubertstr. 81, 35392 Giessen, Germany; (M.H.); (M.A.M.); (T.C.)
| | - Jürg Hamacher
- Lungen-und Atmungsstiftung, Bern, 3012 Bern, Switzerland;
- Pneumology, Clinic for General Internal Medicine, Lindenhofspital Bern, 3012 Bern, Switzerland
- Medical Clinic V-Pneumology, Allergology, Intensive Care Medicine and Environmental Medicine, Faculty of Medicine, Saarland University, University Medical Centre of the Saarland, D-66421 Homburg, Germany
- Institute for Clinical & Experimental Surgery, Faculty of Medicine, Saarland University, D-66421 Homburg, Germany
- Correspondence: (R.L.); (J.H.); Tel.: +41-31-300-35-00 (J.H.)
| |
Collapse
|
33
|
Liang J, Mantelos A, Toh ZQ, Tortorella SM, Ververis K, Vongsvivut J, Bambery KR, Licciardi PV, Hung A, Karagiannis TC. Investigation of potential anti-pneumococcal effects of l-sulforaphane and metabolites: Insights from synchrotron-FTIR microspectroscopy and molecular docking studies. J Mol Graph Model 2020; 97:107568. [PMID: 32097886 DOI: 10.1016/j.jmgm.2020.107568] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 02/10/2020] [Indexed: 01/06/2023]
Abstract
Streptococcus pneumoniae infection can lead to pneumococcal disease, a major cause of mortality in children under the age of five years. In low- and middle-income country settings where pneumococcal disease burden is high, vaccine use is low and widespread antibiotic use has led to increased rates of multi-drug resistant pneumococci. l-sulforaphane (LSF), derived from broccoli and other cruciferous vegetables, has established anti-inflammatory, antioxidant, and anti-microbial properties. Hence, we sought to investigate the potential role of LSF against pneumococcal infection. Using a combination of in vitro and computational methods, the results showed that LSF and relevant metabolites had a potential to reduce pneumococcal adherence through modulation of host receptors, regulation of inflammation, or through direct modification of bacterial factors. Treatment with LSF and metabolites reduced pneumococcal adherence to respiratory epithelial cells. Synchrotron-Fourier transform infrared microspectroscopy (S-FTIR) revealed biochemical changes in protein and lipid profiles of lung epithelial cells following treatment with LSF or metabolites. Molecular docking studies of 116 pneumococcal and 89 host factors revealed a potent effect for the metabolite LSF-glutathione (GSH). A comprehensive list of factors involved in interactions between S. pneumoniae and host cells was compiled to construct a bacterium and host interaction network. Network analysis revealed plasminogen, fibronectin, and RrgA as key factors involved in pneumococcal-host interactions. Therefore, we propose that these constitute critical targets for direct inhibition by LSF and/or metabolites, which may disrupt pneumococcal-host adherence. Overall, our findings further enhance understanding of the potential role of LSF to modulate pneumococcal-host dynamics.
Collapse
Affiliation(s)
- Julia Liang
- Epigenomic Medicine, Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia; School of Science, RMIT University, VIC, 3001, Australia
| | - Anita Mantelos
- Epigenomic Medicine, Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia; Murdoch Children's Research Institute, Melbourne, Parkville, VIC, 3052, Australia; Department of Paediatrics, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Zheng Quan Toh
- Murdoch Children's Research Institute, Melbourne, Parkville, VIC, 3052, Australia
| | - Stephanie M Tortorella
- Epigenomic Medicine, Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | - Katherine Ververis
- Epigenomic Medicine, Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | | | - Keith R Bambery
- ANSTO Australian Synchrotron, 800 Blackburn Road, Clayton, VIC, 3168, Australia
| | - Paul V Licciardi
- Murdoch Children's Research Institute, Melbourne, Parkville, VIC, 3052, Australia; Department of Paediatrics, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Andrew Hung
- School of Science, RMIT University, VIC, 3001, Australia
| | - Tom C Karagiannis
- Epigenomic Medicine, Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia; Department of Clinical Pathology, The University of Melbourne, Parkville, VIC, 3052, Australia.
| |
Collapse
|
34
|
Abstract
PURPOSE OF REVIEW Pneumonia, an inflammatory disease, is the single largest infectious cause of death. Pneumonia has recently been established as an important contributing factor to major adverse cardiovascular events including heart failure. Developing an intermechanistic understanding of pneumonia and cardiovascular disease is crucial for successful future drug therapy and reducing healthcare expenditure. RECENT FINDINGS Up to 30% of patients admitted with pneumonia develop cardiovascular complications such as heart failure within 10 years of hospital discharge. Recent mechanistic studies have identified inflammation, pneumolysin, platelet activation, and thrombus formation at the center of cardiovascular disease progression. SUMMARY In this review, we will detail current knowledge of the mechanistic interaction between pneumonia and development of cardiovascular disease as well as discuss the current and potential drug therapy targets.
Collapse
|
35
|
Smith RP, Barraza I, Quinn RJ, Fortoul MC. The mechanisms and cell signaling pathways of programmed cell death in the bacterial world. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 352:1-53. [PMID: 32334813 DOI: 10.1016/bs.ircmb.2019.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
While programmed cell death was once thought to be exclusive to eukaryotic cells, there are now abundant examples of well regulated cell death mechanisms in bacteria. The mechanisms by which bacteria undergo programmed cell death are diverse, and range from the use of toxin-antitoxin systems, to prophage-driven cell lysis. Moreover, some bacteria have learned how to coopt programmed cell death systems in competing bacteria. Interestingly, many of the potential reasons as to why bacteria undergo programmed cell death may parallel those observed in eukaryotic cells, and may be altruistic in nature. These include protection against infection, recycling of nutrients, to ensure correct morphological development, and in response to stressors. In the following chapter, we discuss the molecular and signaling mechanisms by which bacteria undergo programmed cell death. We conclude by discussing the current open questions in this expanding field.
Collapse
Affiliation(s)
- Robert P Smith
- Department of Biological Sciences, Nova Southeastern University, Fort Lauderdale, FL, United States.
| | - Ivana Barraza
- Department of Biological Sciences, Nova Southeastern University, Fort Lauderdale, FL, United States
| | - Rebecca J Quinn
- Department of Biological Sciences, Nova Southeastern University, Fort Lauderdale, FL, United States
| | - Marla C Fortoul
- Department of Biological Sciences, Nova Southeastern University, Fort Lauderdale, FL, United States
| |
Collapse
|
36
|
Domain 4 of pneumolysin from Streptococcus pneumoniae is a multifunctional domain contributing TLR4 activating and hemolytic activity. Biochem Biophys Res Commun 2019; 517:596-602. [PMID: 31395343 DOI: 10.1016/j.bbrc.2019.07.063] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 07/18/2019] [Indexed: 11/21/2022]
Abstract
The pneumolysin (Ply) protein of Streptococcus pneumoniae is composed of four domains and possesses several different but related activities. In this study, recombinant Ply and two truncated forms, Ply domain 1-3 and Ply domain 4 (rPly4), were expressed and characterized regarding their participation in apoptosis, the stimulation of cytokine production, hemolytic activity and virulence. rPly4 activated murine bone marrow-derived dendritic cells in a Toll-like receptor (TLR) 4-dependent manner. The rPly4 alone was able to produce hemolytic activity at high concertation and penetrate the lipid bilayer. We further demonstrated that domain 4 of Ply involved in the virulence of the bacteria in mouse model. In the absence of apoptotic activity, the virulence level caused by rPly4 was similar to that of full length Ply. Our data suggested that domain 4 of Ply alone with TLR4 agonist and hemolytic activity may play roles in virulence of Streptococcus pneumoniae.
Collapse
|
37
|
Translating Recent Microbiome Insights in Otitis Media into Probiotic Strategies. Clin Microbiol Rev 2019; 32:32/4/e00010-18. [PMID: 31270125 DOI: 10.1128/cmr.00010-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The microbiota of the upper respiratory tract (URT) protects the host from bacterial pathogenic colonization by competing for adherence to epithelial cells and by immune response regulation that includes the activation of antimicrobial and (anti-)inflammatory components. However, environmental or host factors can modify the microbiota to an unstable community that predisposes the host to infection or inflammation. One of the URT diseases most often encountered in children is otitis media (OM). The role of pathogenic bacteria like Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in the pathogenesis of OM is well documented. Results from next-generation-sequencing (NGS) studies reveal other bacterial taxa involved in OM, such as Turicella and Alloiococcus Such studies can also identify bacterial taxa that are potentially protective against URT infections, whose beneficial action needs to be substantiated in relevant experimental models and clinical trials. Of note, lactic acid bacteria (LAB) are members of the URT microbiota and associated with a URT ecosystem that is deemed healthy, based on NGS and some experimental and clinical studies. These observations have formed the basis of this review, in which we describe the current knowledge of the molecular and clinical potential of LAB in the URT, which is currently underexplored in microbiome and probiotic research.
Collapse
|
38
|
Surve MV, Banerjee A. Cell-to-cell phenotypic heterogeneity in pneumococcal pathogenesis. Future Microbiol 2019; 14:647-651. [PMID: 31148481 DOI: 10.2217/fmb-2019-0096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Manalee Vishnu Surve
- Bacterial Pathogenesis Lab, Department of Biosciences & Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Anirban Banerjee
- Bacterial Pathogenesis Lab, Department of Biosciences & Bioengineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| |
Collapse
|
39
|
Laterre PF, Colin G, Dequin PF, Dugernier T, Boulain T, Azeredo da Silveira S, Lajaunias F, Perez A, François B. CAL02, a novel antitoxin liposomal agent, in severe pneumococcal pneumonia: a first-in-human, double-blind, placebo-controlled, randomised trial. THE LANCET. INFECTIOUS DISEASES 2019; 19:620-630. [PMID: 31056427 DOI: 10.1016/s1473-3099(18)30805-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/10/2018] [Accepted: 12/14/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND Severe community-acquired pneumonia caused by Streptococcus pneumoniae is associated with high morbidity and mortality rates. CAL02, a novel antitoxin agent with an unprecedented mode of action, consists of liposomes that capture bacterial toxins known to dysregulate inflammation, cause organ damage, and impede immune defence. We aimed to assess the safety of CAL02 as an add-on therapy to antibiotics. METHODS This randomised, double-blind, multicentre, placebo-controlled trial was done in ten intensive care units (ICUs) in France and Belgium (but only six units enrolled patients), in patients with severe community-acquired pneumococcal pneumonia who required ICU admission and had been identified as being infected with S pneumoniae. We randomly assigned participants in two stages-the first stage randomly assigned six patients (1:1) to either low-dose CAL02 or placebo, and the second stage randomly assigned 18 patients (14:4) to either high-dose CAL02 or placebo, and stratified in four blocks (4:1, 4:1, 3:1, and 3:1), in addition to standard of care. Block randomisation was done with a computer-generated random number list. Participants, investigators, other site study personnel, the sponsor, and the sponsor's designees involved in study management and monitoring were masked to the randomisation list and treatment assignment. Patients were treated with low-dose (4 mg/kg) or high-dose (16 mg/kg) CAL02 or placebo (saline), in addition to standard antibiotic therapy. Two intravenous doses of study treatment were infused, with a 24 h interval, at a concentration of 10 mg/mL, stepwise, over a maximum of 2 h on days 1 and 2. The primary objective of the study was to assess the safety and tolerability of low-dose and high-dose CAL02 in patients with severe community-acquired pneumonia treated with standard antibiotic therapy, and the primary analysis was done on the safety population (all patients who received at least one dose of the study treatment). Efficacy was a secondary outcome. This trial is registered with ClinicalTrials.gov, number NCT02583373. FINDINGS Between March 21, 2016, and Jan 13, 2018, we screened 280 patients with community-acquired pneumonia. 19 patients were enrolled and randomly assigned, resulting in 13 patients in the CAL02 groups (three assigned to low-dose CAL02 and ten assigned to high-dose CAL02) and six in the placebo group. One patient randomly assigned to placebo was allocated to the wrong treatment group and received high-dose CAL02 instead of placebo. Thus, 14 patients received CAL02 (three received low-dose CAL02 and 11 received high-dose CAL02) and five patients received placebo, constituting the safety population. At baseline, the mean APACHE II score for the total study population was 21·5 (SD 4·9; 95% CI 19·3-23·7) and 11 (58%) of 19 patients had septic shock. Adverse events occurred in 12 (86%) of 14 patients in the CAL02 treatment groups combined and all five (100%) patients in the placebo group. Serious adverse events occurred in four (29%) of 14 patients in the CAL02 treatment groups combined and two (40%) of five patients in the placebo group. One non-serious adverse event (mild increase in triglycerides) in a patient in the high-dose CAL02 group was reported as related to study drug. However, analysis of the changes in triglyceride levels in the CAL02 groups compared with the placebo group revealed no correlation with administration of CAL02. No adverse events were linked to local tolerability events. All patients, apart from one who died in the low CAL02 group (death not related to the study drug) achieved clinical cure at the test of cure visit between days 15 and 22. The sequential organ failure assessment score decreased by mean 65·0% (95% CI 50·7-79·4) in the combined CAL02 groups compared with 29·2% (12·8-45·5) in the placebo group between baseline and day 8. INTERPRETATION The nature of adverse events was consistent with the profile of the study population and CAL02 showed a promising safety profile and tolerability. However, the difference between high-dose and low-dose CAL02 could not be assessed in this study. Efficacy was in line with the expected benefits of neutralising toxins. The results of this study support further clinical development of CAL02 and provide a solid basis for a larger clinical study. FUNDING Combioxin.
Collapse
Affiliation(s)
- Pierre-François Laterre
- Intensive Care Unit, Cliniques Universitaires Saint-Luc, Université catholique de Louvain (UCL), Brussels, Belgium.
| | - Gwenhael Colin
- Medical-Surgical Intensive Care Unit, District Hospital Center, La Roche-sur-Yon, France
| | | | | | - Thierry Boulain
- Service de Médecine Intensive Réanimation, Hôpital La Source, Centre Hospitalier Régional d'Orléans, Orléans, France
| | | | | | | | - Bruno François
- Medical-Surgical Intensive Care Unit, University Hospital Limoges Dupuytren Hospital, Limoges, France; Inserm CIC-1435, University Hospital Limoges Dupuytren Hospital, Limoges, France; Inserm UMR 1092, Faculté de Médecine, Université de Limoges, Limoges, France
| |
Collapse
|
40
|
Sharma P, Sharma N, Mishra P, Joseph J, Mishra DK, Garg P, Roy S. Differential Expression of Antimicrobial Peptides in Streptococcus pneumoniae Keratitis and STAT3-Dependent Expression of LL-37 by Streptococcus pneumoniae in Human Corneal Epithelial Cells. Pathogens 2019; 8:pathogens8010031. [PMID: 30845777 PMCID: PMC6470555 DOI: 10.3390/pathogens8010031] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/27/2019] [Accepted: 03/01/2019] [Indexed: 12/15/2022] Open
Abstract
Streptococcus pneumoniae is the leading cause of bacterial keratitis in the developing world with a growing trend of acquiring resistance against various antibiotics. In the current study, we determined the expression of different antimicrobial peptides (AMPs) in response to S. pneumoniae in patients, as well as in primary and immortalized human corneal epithelial cells. We further focused on LL-37 and determined its expression in human cornea infected with S. pneumoniae and studied the killing ability of LL-37 against S. pneumoniae. The expression of AMPs was determined by quantitative PCR and the phosphorylation of signaling proteins was evaluated by immunoblot analysis. LL-37 expression was also determined by immunofluorescence and Western blot method and the killing ability of LL-37 against S. pneumoniae was determined by colony-forming units. Differential expression of antimicrobial peptides was observed in patients with S. pneumoniae keratitis. Although S. pneumoniae induced expression of the AMPs in human corneal epithelial cells (HCEC), it did not induce AMP expression in U937, a human monocyte cell line. S. pneumoniae also caused activation of nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB)and mitogen activated protein kinase (MAPK) pathways in corneal epithelial cells. LL-37 was found to be effective against both laboratory and clinical strains of S. pneumoniae. LL-37 induction by S. pneumoniae in human corneal epithelial cells was mediated by signal transducer and activator of transcription 3 (STAT3) activation, and inhibition of STAT3 activation significantly reduced LL-37 expression. Our study determines an extensive profile of AMPs expressed in the human cornea during S. pneumoniae infection, and suggests the potential of LL-37 to be developed as an alternative therapeutic intervention to fight increasing antibiotic resistance among bacteria.
Collapse
Affiliation(s)
- Prerana Sharma
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
- Department of Animal Sciences, University of Hyderabad, Hyderabad 500046, India.
| | - Natalia Sharma
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Priyasha Mishra
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Joveeta Joseph
- Jhaveri Microbiology Centre, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Dilip K Mishra
- Pathology Department, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Prashant Garg
- Tej Kohli Cornea Institute, Hyderabad 500034, India.
| | - Sanhita Roy
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
- Tej Kohli Cornea Institute, Hyderabad 500034, India.
| |
Collapse
|
41
|
Divyakolu S, Chikkala R, Ratnakar KS, Sritharan V. Hemolysins of <i>Staphylococcus aureus</i>—An Update on Their Biology, Role in Pathogenesis and as Targets for Anti-Virulence Therapy. ACTA ACUST UNITED AC 2019. [DOI: 10.4236/aid.2019.92007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
42
|
Lee J, Suh E, Byambabaatar S, Lee S, Kim H, Jin KS, Ree M. Structural Characteristics of Pneumolysin and Its Domains in a Biomimetic Solution. ACS OMEGA 2018; 3:9453-9461. [PMID: 31459080 PMCID: PMC6644606 DOI: 10.1021/acsomega.8b01212] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/06/2018] [Indexed: 06/10/2023]
Abstract
Pneumolysin (PLY) and its truncated fragments, domains 1-3 (D1-3), and domain 4 (D4), were purified as recombinant proteins after being cloned and over-expressed in Escherichia coli. The three-dimensional structures of these proteins were quantitatively investigated in a biomimetic condition, phosphate buffered saline (PBS) by synchrotron X-ray scattering. X-ray scattering analysis revealed important structural features including structural parameters. PLY was present as a monomeric form in PBS. The monomeric form resembled its crystallographic structure with a discrepancy of only 6.3%, confirming that PLY forms a stable structure and, thus, retains its structure in the crystalline state and even in PBS solution. D4 was also present as a monomeric form, but its structure was very different from that of the corresponding part in the crystallographic PLY structure; the discrepancy was 92.0%. Such a dissimilar structure might originate from a less folded-chain conformation. This result suggested that the structure of D4 is highly dependent on the crystalline or solution state and further on the presence or absence of the D1-3 unit. In contrast, D1-3 was dimeric rather than monomeric. Its structure was close to the most probable dimeric form of the corresponding part in the crystallographic PLY structure with 13.1% discrepancy. This fact indicated that the D1-3 unit forms a stable structure and, indeed, such structure is well maintained in the crystalline state as well as in PBS although presented as a dimer. This result further supported that the whole structural stability of PLY is mainly attributed to the structure of D1-3. All of PLY, D1-3, and D4 revealed aggregation tendencies during purification and storage. Overall, the structural characteristics of PLY and its domains in PBS may correlate to the PLY oligomer formation yielding large pore structures for the penetration of cell membranes.
Collapse
Affiliation(s)
- Jongchan Lee
- Department
of Chemistry, Division of Advanced Materials Science,
and Polymer Research Institute and Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Eunae Suh
- Department
of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 38066, Republic of Korea
| | - Sumiya Byambabaatar
- Department
of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 38066, Republic of Korea
| | - Soomin Lee
- Department
of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 38066, Republic of Korea
| | - Heesoo Kim
- Department
of Microbiology and Dongguk Medical Institute, Dongguk University College of Medicine, Gyeongju 38066, Republic of Korea
| | - Kyeong Sik Jin
- Department
of Chemistry, Division of Advanced Materials Science,
and Polymer Research Institute and Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Moonhor Ree
- Department
of Chemistry, Division of Advanced Materials Science,
and Polymer Research Institute and Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| |
Collapse
|
43
|
Al-Obaidi MMJ, Desa MNM. Mechanisms of Blood Brain Barrier Disruption by Different Types of Bacteria, and Bacterial-Host Interactions Facilitate the Bacterial Pathogen Invading the Brain. Cell Mol Neurobiol 2018; 38:1349-1368. [PMID: 30117097 DOI: 10.1007/s10571-018-0609-2] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 08/06/2018] [Indexed: 12/19/2022]
Abstract
This review aims to elucidate the different mechanisms of blood brain barrier (BBB) disruption that may occur due to invasion by different types of bacteria, as well as to show the bacteria-host interactions that assist the bacterial pathogen in invading the brain. For example, platelet-activating factor receptor (PAFR) is responsible for brain invasion during the adhesion of pneumococci to brain endothelial cells, which might lead to brain invasion. Additionally, the major adhesin of the pneumococcal pilus-1, RrgA is able to bind the BBB endothelial receptors: polymeric immunoglobulin receptor (pIgR) and platelet endothelial cell adhesion molecule (PECAM-1), thus leading to invasion of the brain. Moreover, Streptococcus pneumoniae choline binding protein A (CbpA) targets the common carboxy-terminal domain of the laminin receptor (LR) establishing initial contact with brain endothelium that might result in BBB invasion. Furthermore, BBB disruption may occur by S. pneumoniae penetration through increasing in pro-inflammatory markers and endothelial permeability. In contrast, adhesion, invasion, and translocation through or between endothelial cells can be done by S. pneumoniae without any disruption to the vascular endothelium, upon BBB penetration. Internalins (InlA and InlB) of Listeria monocytogenes interact with its cellular receptors E-cadherin and mesenchymal-epithelial transition (MET) to facilitate invading the brain. L. monocytogenes species activate NF-κB in endothelial cells, encouraging the expression of P- and E-selectin, intercellular adhesion molecule 1 (ICAM-1), and Vascular cell adhesion protein 1 (VCAM-1), as well as IL-6 and IL-8 and monocyte chemoattractant protein-1 (MCP-1), all these markers assist in BBB disruption. Bacillus anthracis species interrupt both adherens junctions (AJs) and tight junctions (TJs), leading to BBB disruption. Brain microvascular endothelial cells (BMECs) permeability and BBB disruption are induced via interendothelial junction proteins reduction as well as up-regulation of IL-1α, IL-1β, IL-6, TNF-α, MCP-1, macrophage inflammatory proteins-1 alpha (MIP1α) markers in Staphylococcus aureus species. Streptococcus agalactiae or Group B Streptococcus toxins (GBS) enhance IL-8 and ICAM-1 as well as nitric oxide (NO) production from endothelial cells via the expression of inducible nitric oxide synthase (iNOS) enhancement, resulting in BBB disruption. While Gram-negative bacteria, Haemophilus influenza OmpP2 is able to target the common carboxy-terminal domain of LR to start initial interaction with brain endothelium, then invade the brain. H. influenza type b (HiB), can induce BBB permeability through TJ disruption. LR and PAFR binding sites have been recognized as common routes of CNS entrance by Neisseria meningitidis. N. meningitidis species also initiate binding to BMECs and induces AJs deformation, as well as inducing specific cleavage of the TJ component occludin through the release of host MMP-8. Escherichia coli bind to BMECs through LR, resulting in IL-6 and IL-8 release and iNOS production, as well as resulting in disassembly of TJs between endothelial cells, facilitating BBB disruption. Therefore, obtaining knowledge of BBB disruption by different types of bacterial species will provide a picture of how the bacteria enter the central nervous system (CNS) which might support the discovery of therapeutic strategies for each bacteria to control and manage infection.
Collapse
Affiliation(s)
- Mazen M Jamil Al-Obaidi
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
| | - Mohd Nasir Mohd Desa
- Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
- Halal Products Research Institute, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.
| |
Collapse
|
44
|
Brooks LRK, Mias GI. Streptococcus pneumoniae's Virulence and Host Immunity: Aging, Diagnostics, and Prevention. Front Immunol 2018; 9:1366. [PMID: 29988379 PMCID: PMC6023974 DOI: 10.3389/fimmu.2018.01366] [Citation(s) in RCA: 118] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/01/2018] [Indexed: 12/14/2022] Open
Abstract
Streptococcus pneumoniae is an infectious pathogen responsible for millions of deaths worldwide. Diseases caused by this bacterium are classified as pneumococcal diseases. This pathogen colonizes the nasopharynx of its host asymptomatically, but overtime can migrate to sterile tissues and organs and cause infections. Pneumonia is currently the most common pneumococcal disease. Pneumococcal pneumonia is a global health concern and vastly affects children under the age of five as well as the elderly and individuals with pre-existing health conditions. S. pneumoniae has a large selection of virulence factors that promote adherence, invasion of host tissues, and allows it to escape host immune defenses. A clear understanding of S. pneumoniae's virulence factors, host immune responses, and examining the current techniques available for diagnosis, treatment, and disease prevention will allow for better regulation of the pathogen and its diseases. In terms of disease prevention, other considerations must include the effects of age on responses to vaccines and vaccine efficacy. Ongoing work aims to improve on current vaccination paradigms by including the use of serotype-independent vaccines, such as protein and whole cell vaccines. Extending our knowledge of the biology of, and associated host immune response to S. pneumoniae is paramount for our improvement of pneumococcal disease diagnosis, treatment, and improvement of patient outlook.
Collapse
Affiliation(s)
- Lavida R. K. Brooks
- Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, United States
- Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, United States
| | - George I. Mias
- Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, United States
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, United States
| |
Collapse
|
45
|
Xu G, Liu X, Wang Y. The cerebral protective effect and mechanism of action of vitamin B6 adjuvant ceftriaxone in experimental pneumococcal meningitis. Brain Res 2018; 1695:53-64. [PMID: 29800553 DOI: 10.1016/j.brainres.2018.05.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 05/18/2018] [Accepted: 05/20/2018] [Indexed: 12/27/2022]
Abstract
BACKGROUND Pneumococcal meningitis is one of the most common infectious diseases with a high-mortality rate and long-term neurological sequelae, affecting up to 50% of survivors. Pneumococcal compounds are pro-inflammatory mediators that induce an innate immune response and tryptophan degradation through the kynurenine pathway. Vitamin B6 (vitB6) is an important vitamin which acts as a cofactor at the active sites of enzymes that catalyze a great number of reactions involved in the metabolism of tryptophan through the kynurenine pathway and may thus limit the accumulation of neurotoxic metabolites and preserve the cellular energy status. The aim of this study was to investigate the neuroprotective effect of adjuvant treatment with vitB6 in pneumococcal meningitis. METHODS The effects of vitB6 on the clinical symptoms, the expression of kynureninase (KYN), Kynurenic acid (KYNA), nicotinamide adenine dinucleotide (NAD) and cytokines in brain tissue and memory of infant Wistar rats subjected to pneumococcal meningitis were researched. At the same time, Kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 was applied in order to further investigate the brain protective effect of vitB6 in bacterial meningitis. RESULTS Adjuvant therapy of bacterial meningitis with vitB6 could improve the clinical symptoms, learning performance, lead to the maintenance of cellular NAD+ and ATP homeostasis and significantly down-regulate the levels of cytokines in the brain tissue by affecting the KYN pathway. CONCLUSIONS Adjuvant treatment with vitB6 in pneumococcal meningitis could exert neuroprotective effect via increasing the preservation of cellular energy through affecting the KYN pathway and reducing of the inflammatory response.
Collapse
Affiliation(s)
- Guixia Xu
- The Pediatric Department of Qilu Hospital, Shandong University, PR China; The Pediatric Department of the Second People's Hospital of Liaocheng, PR China
| | - Xinjie Liu
- The Pediatric Department of Qilu Hospital, Shandong University, PR China.
| | - Ying Wang
- The Pediatric Department of the People's Hospital in Zoucheng, PR China
| |
Collapse
|
46
|
|
47
|
Anderson R, Nel JG, Feldman C. Multifaceted Role of Pneumolysin in the Pathogenesis of Myocardial Injury in Community-Acquired Pneumonia. Int J Mol Sci 2018; 19:E1147. [PMID: 29641429 PMCID: PMC5979279 DOI: 10.3390/ijms19041147] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 03/14/2018] [Accepted: 03/21/2018] [Indexed: 12/14/2022] Open
Abstract
Pneumolysin (PLY), a member of the family of Gram-positive bacterial, cholesterol-dependent, β-barrel pore-forming cytolysins, is the major protein virulence factor of the dangerous respiratory pathogen, Streptococcus pneumoniae (pneumococcus). PLY plays a major role in the pathogenesis of community-acquired pneumonia (CAP), promoting colonization and invasion of the upper and lower respiratory tracts respectively, as well as extra-pulmonary dissemination of the pneumococcus. Notwithstanding its role in causing acute lung injury in severe CAP, PLY has also been implicated in the development of potentially fatal acute and delayed-onset cardiovascular events, which are now recognized as being fairly common complications of this condition. This review is focused firstly on updating mechanisms involved in the immunopathogenesis of PLY-mediated myocardial damage, specifically the direct cardiotoxic and immunosuppressive activities, as well as the indirect pro-inflammatory/pro-thrombotic activities of the toxin. Secondly, on PLY-targeted therapeutic strategies including, among others, macrolide antibiotics, natural product antagonists, cholesterol-containing liposomes, and fully humanized monoclonal antibodies, as well as on vaccine-based preventive strategies. These sections are preceded by overviews of CAP in general, the role of the pneumococcus as the causative pathogen, the occurrence and types of CAP-associated cardiac complication, and the structure and biological activities of PLY.
Collapse
Affiliation(s)
- Ronald Anderson
- Department of Immunology and Institute for Cellular and Molecular Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria 0001, South Africa.
| | - Jan G Nel
- Department of Haematology, Faculty of Health Sciences, University of Pretoria and Tshwane Academic Division of the National Health Laboratory Service, Pretoria 0001, South Africa.
| | - Charles Feldman
- Division of Pulmonology, Department of Internal Medicine, Charlotte Maxeke Johannesburg Academic Hospital and Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 0002, South Africa.
| |
Collapse
|
48
|
DNA-release by Streptococcus pneumoniae autolysin LytA induced Krueppel-like factor 4 expression in macrophages. Sci Rep 2018; 8:5723. [PMID: 29636524 PMCID: PMC5893607 DOI: 10.1038/s41598-018-24152-1] [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: 07/24/2017] [Accepted: 03/20/2018] [Indexed: 12/22/2022] Open
Abstract
The recruitment of myeloid cells to the lung is of utmost importance for the elimination of invading pathogens. We investigated the Streptococcus pneumoniae-dependent induction mechanism of KLF4 in macrophages as a potential regulator of the macrophage immune response. We demonstrated that only viable pneumococci, which have direct contact to the host cells and release LytA-dependent DNA, induced KLF4. Exogenous supplementation of pneumococcal, other bacterial, eukaryotic foreign (human) or self (mouse) DNA to autolysis-deficient pneumococci restored (at least in part) pneumococci-related KLF4 induction. Experiments using TLR9, TRIF and MyD88 knockout macrophages revealed that TLR9, TRIF and MyD88 were partly involved in the S. pneumoniae-induced KLF4 expression. BMMs missing important DNA receptor related molecules (ASC−/−, STING−/−) showed no differences in pneumococci-related KLF4 expression. Similar results were observed with IFNAR−/− BMMs and Type I IFN stimulated cells. LyzMcre mediated knockdown of KLF4 in BMMs resulted in a decreased secretion of proinflammatory cytokines and enhanced IL-10 release. In summary, we showed that pneumococci-related KLF4 induction in macrophages is mediated via a PAMP-DAMP induction mechanism involving a hitherto unknown host cell DNA sensor leading to a more proinflammatory macrophage phenotype.
Collapse
|
49
|
Azeredo da Silveira S, Perez A. Improving the fate of severely infected patients: the promise of anti-toxin treatments and superiority trials. Expert Rev Anti Infect Ther 2017; 15:973-975. [DOI: 10.1080/14787210.2017.1400908] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
50
|
Principi N, Esposito S. Development of pneumococcal vaccines over the last 10 years. Expert Opin Biol Ther 2017; 18:7-17. [DOI: 10.1080/14712598.2018.1384462] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Nicola Principi
- Pediatric Highly Intensive Care Unit, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Università degli Studi di Milano, Milan, Italy
| | - Susanna Esposito
- Paediatric Clinic, Department of Surgical and Biomedical Sciences, Università degli Studi di Perugia, Perugia, Italy
| |
Collapse
|