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Schmidt G. Some Examples of Bacterial Toxins as Tools. Toxins (Basel) 2024; 16:202. [PMID: 38787054 PMCID: PMC11125981 DOI: 10.3390/toxins16050202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/18/2024] [Accepted: 04/20/2024] [Indexed: 05/25/2024] Open
Abstract
Pathogenic bacteria produce diverse protein toxins to disturb the host's defenses. This includes the opening of epithelial barriers to establish bacterial growth in deeper tissues of the host and to modulate immune cell functions. To achieve this, many toxins share the ability to enter mammalian cells, where they catalyze the modification of cellular proteins. The enzymatic activity is diverse and ranges from ribosyl- or glycosyl-transferase activity, the deamidation of proteins, and adenylate-cyclase activity to proteolytic cleavage. Protein toxins are highly active enzymes often with tight specificity for an intracellular protein or a protein family coupled with the intrinsic capability of entering mammalian cells. A broad understanding of their molecular mechanisms established bacterial toxins as powerful tools for cell biology. Both the enzymatic part and the pore-forming/protein transport capacity are currently used as tools engineered to study signaling pathways or to transport cargo like labeled compounds, nucleic acids, peptides, or proteins directly into the cytosol. Using several representative examples, this review is intended to provide a short overview of the state of the art in the use of bacterial toxins or parts thereof as tools.
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Affiliation(s)
- Gudula Schmidt
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Albertstr. 25, 79104 Freiburg, Germany
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2
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Badami GD, La Manna MP, Di Carlo P, Stanek O, Linhartova I, Caccamo N, Sebo P, Dieli F. Delivery of Mycobacterium tuberculosis epitopes by Bordetella pertussis adenylate cyclase toxoid expands HLA-E-restricted cytotoxic CD8 + T cells. Front Immunol 2023; 14:1289212. [PMID: 38106407 PMCID: PMC10722248 DOI: 10.3389/fimmu.2023.1289212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 11/10/2023] [Indexed: 12/19/2023] Open
Abstract
Introduction Tuberculosis (TB) remains the first cause of death from infection caused by a bacterial pathogen. Chemotherapy does not eradicate Mycobacterium tuberculosis (Mtb) from human lungs, and the pathogen causes a latent tuberculosis infection that cannot be prevented by the currently available Bacille Calmette Guerin (BCG) vaccine, which is ineffective in the prevention of pulmonary TB in adults. HLA-E-restricted CD8+ T lymphocytes are essential players in protective immune responses against Mtb. Hence, expanding this population in vivo or ex vivo may be crucial for vaccination or immunotherapy against TB. Methods The enzymatically inactive Bordetella pertussis adenylate cyclase (CyaA) toxoid is an effective tool for delivering peptide epitopes into the cytosol of antigen-presenting cells (APC) for presentation and stimulation of specific CD8+ T-cell responses. In this study, we have investigated the capacity of the CyaA toxoid to deliver Mtb epitopes known to bind HLA-E for the expansion of human CD8+ T cells in vitro. Results Our results show that the CyaA-toxoid containing five HLA-E-restricted Mtb epitopes causes significant expansion of HLA-E-restricted antigen-specific CD8+ T cells, which produce IFN-γ and exert significant cytotoxic activity towards peptide-pulsed macrophages. Discussion HLA-E represents a promising platform for the development of new vaccines; our study indicates that the CyaA construct represents a suitable delivery system of the HLA-E-binding Mtb epitopes for ex vivo and in vitro expansion of HLA-E-restricted CD8+ T cells inducing a predominant Tc1 cytokine profile with a significant increase of IFN-γ production, for prophylactic and immunotherapeutic applications against Mtb.
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Affiliation(s)
- Giusto D. Badami
- Central Laboratory of Advanced Diagnosis and Biomedical Research (CLADIBIOR), AOUP Paolo Giaccone, Palermo, Italy
- Department of Biomedicine, Neuroscience and Advanced Diagnosis (BIND), University of Palermo, Palermo, Italy
| | - Marco P. La Manna
- Central Laboratory of Advanced Diagnosis and Biomedical Research (CLADIBIOR), AOUP Paolo Giaccone, Palermo, Italy
- Department of Biomedicine, Neuroscience and Advanced Diagnosis (BIND), University of Palermo, Palermo, Italy
| | - Paola Di Carlo
- Department of Sciences for Health Promotion and Mother-Child Care “G. D’Alessandro”, University of Palermo, Palermo, Italy
| | - Ondrej Stanek
- Laboratory of Molecular Biology of Bacterial Pathogen, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Irena Linhartova
- Laboratory of Molecular Biology of Bacterial Pathogen, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Nadia Caccamo
- Central Laboratory of Advanced Diagnosis and Biomedical Research (CLADIBIOR), AOUP Paolo Giaccone, Palermo, Italy
- Department of Biomedicine, Neuroscience and Advanced Diagnosis (BIND), University of Palermo, Palermo, Italy
| | - Peter Sebo
- Laboratory of Molecular Biology of Bacterial Pathogen, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czechia
| | - Francesco Dieli
- Central Laboratory of Advanced Diagnosis and Biomedical Research (CLADIBIOR), AOUP Paolo Giaccone, Palermo, Italy
- Department of Biomedicine, Neuroscience and Advanced Diagnosis (BIND), University of Palermo, Palermo, Italy
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Holban AM, Gregoire CM, Gestal MC. Conquering the host: Bordetella spp. and Pseudomonas aeruginosa molecular regulators in lung infection. Front Microbiol 2022; 13:983149. [PMID: 36225372 PMCID: PMC9549215 DOI: 10.3389/fmicb.2022.983149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/17/2022] [Indexed: 11/27/2022] Open
Abstract
When bacteria sense cues from the host environment, stress responses are activated. Two component systems, sigma factors, small RNAs, ppGpp stringent response, and chaperones start coordinate the expression of virulence factors or immunomodulators to allow bacteria to respond. Although, some of these are well studied, such as the two-component systems, the contribution of other regulators, such as sigma factors or ppGpp, is increasingly gaining attention. Pseudomonas aeruginosa is the gold standard pathogen for studying the molecular mechanisms to sense and respond to environmental cues. Bordetella spp., on the other hand, is a microbial model for studying host-pathogen interactions at the molecular level. These two pathogens have the ability to colonize the lungs of patients with chronic diseases, suggesting that they have the potential to share a niche and interact. However, the molecular networks that facilitate adaptation of Bordetella spp. to cues are unclear. Here, we offer a side-by-side comparison of what is known about these diverse molecular mechanisms that bacteria utilize to counteract host immune responses, while highlighting the relatively unexplored interactions between them.
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Affiliation(s)
- Alina M. Holban
- Research Institute of the University of Bucharest (ICUB), Bucharest, Romania
- Department of Microbiology and Immunology, Faculty of Biology, University of Bucharest, Bucharest, Romania
| | - Courtney M. Gregoire
- Department of Microbiology and Immunology, Louisiana State University Health Science Center, Shreveport, LA, United States
| | - Monica C. Gestal
- Department of Microbiology and Immunology, Louisiana State University Health Science Center, Shreveport, LA, United States
- *Correspondence: Monica C. Gestal, ;
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D’haese S, Laeremans T, den Roover S, Allard SD, Vanham G, Aerts JL. Efficient Induction of Antigen-Specific CD8+ T-Cell Responses by Cationic Peptide-Based mRNA Nanoparticles. Pharmaceutics 2022; 14:pharmaceutics14071387. [PMID: 35890284 PMCID: PMC9321026 DOI: 10.3390/pharmaceutics14071387] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 06/24/2022] [Accepted: 06/28/2022] [Indexed: 11/16/2022] Open
Abstract
A major determinant for the success of mRNA-based vaccines is the composition of the nanoparticles (NPs) used for formulation and delivery. Cationic peptides represent interesting candidate carriers for mRNA, since they have been shown to efficiently deliver nucleic acids to eukaryotic cells. mRNA NPs based on arginine-rich peptides have previously been demonstrated to induce potent antigen-specific CD8+ T-cell responses. We therefore compared the histidine-rich amphipathic peptide LAH4-L1 (KKALLAHALHLLALLALHLAHALKKA) to the fully substituted arginine variant (LAH4-L1R) for their capacity to formulate mRNA and transfect dendritic cells (DCs). Although both peptides encapsulated mRNA to the same extent, and showed excellent uptake in DCs, the gene expression level was significantly higher for LAH4-L1. The LAH4-L1–mRNA NPs also resulted in enhanced antigen presentation in the context of MHC I compared to LAH4-L1R in primary murine CD103+ DCs. Both peptides induced DC maturation and inflammasome activation. Subsequent ex vivo stimulation of OT-I splenocytes with transfected CD103+ DCs resulted in a high proportion of polyfunctional CD8+ T cells for both peptides. In addition, in vivo immunization with LAH4-L1 or LAH4-L1R–mRNA NPs resulted in proliferation of antigen-specific T cells. In conclusion, although LAH4-L1 outperformed LAH4-L1R in terms of transfection efficiency, the immune stimulation ex vivo and in vivo was equally efficient.
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Affiliation(s)
- Sigrid D’haese
- Laboratory for Neuro-Aging and Viro-Immunotherapy (NAVI), Faculty of Pharmacy and Medicine, Vrije Universiteit Brussel, 1090 Brussels, Belgium; (S.D.); (T.L.); (S.d.R.)
| | - Thessa Laeremans
- Laboratory for Neuro-Aging and Viro-Immunotherapy (NAVI), Faculty of Pharmacy and Medicine, Vrije Universiteit Brussel, 1090 Brussels, Belgium; (S.D.); (T.L.); (S.d.R.)
| | - Sabine den Roover
- Laboratory for Neuro-Aging and Viro-Immunotherapy (NAVI), Faculty of Pharmacy and Medicine, Vrije Universiteit Brussel, 1090 Brussels, Belgium; (S.D.); (T.L.); (S.d.R.)
| | - Sabine D. Allard
- Department of Internal Medicine (IRG), Vrije Universiteit Brussel, Universitair Ziekenhuis Brussel, 1090 Brussels, Belgium;
| | - Guido Vanham
- Department of Virology, Institute of Tropical Medicine, University of Antwerp, 2000 Antwerp, Belgium;
| | - Joeri L. Aerts
- Laboratory for Neuro-Aging and Viro-Immunotherapy (NAVI), Faculty of Pharmacy and Medicine, Vrije Universiteit Brussel, 1090 Brussels, Belgium; (S.D.); (T.L.); (S.d.R.)
- Correspondence:
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Holubova J, Stanek O, Juhasz A, Hamidou Soumana I, Makovicky P, Sebo P. The Fim and FhaB adhesins play a crucial role in nasal cavity infection and Bordetella pertussis transmission in a novel mouse catarrhal infection model. PLoS Pathog 2022; 18:e1010402. [PMID: 35395059 PMCID: PMC9020735 DOI: 10.1371/journal.ppat.1010402] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 04/20/2022] [Accepted: 02/28/2022] [Indexed: 02/07/2023] Open
Abstract
Pulmonary infections caused by Bordetella pertussis used to be the prime cause of infant mortality in the pre-vaccine era and mouse models of pertussis pneumonia served in characterization of B. pertussis virulence mechanisms. However, the biologically most relevant catarrhal disease stage and B. pertussis transmission has not been adequately reproduced in adult mice due to limited proliferation of the human-adapted pathogen on murine nasopharyngeal mucosa. We used immunodeficient C57BL/6J MyD88 KO mice to achieve B. pertussis proliferation to human-like high counts of 108 viable bacteria per nasal cavity to elicit rhinosinusitis accompanied by robust shedding and transmission of B. pertussis bacteria to adult co-housed MyD88 KO mice. Experiments with a comprehensive set of B. pertussis mutants revealed that pertussis toxin, adenylate cyclase toxin-hemolysin, the T3SS effector BteA/BopC and several other known virulence factors were dispensable for nasal cavity infection and B. pertussis transmission in the immunocompromised MyD88 KO mice. In contrast, mutants lacking the filamentous hemagglutinin (FhaB) or fimbriae (Fim) adhesins infected the nasal cavity poorly, shed at low levels and failed to productively infect co-housed MyD88 KO or C57BL/6J mice. FhaB and fimbriae thus appear to play a critical role in B. pertussis transmission. The here-described novel murine model of B. pertussis-induced nasal catarrh opens the way to genetic dissection of host mechanisms involved in B. pertussis shedding and to validation of key bacterial transmission factors that ought to be targeted by future pertussis vaccines.
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Affiliation(s)
- Jana Holubova
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Ondrej Stanek
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Attila Juhasz
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Illiassou Hamidou Soumana
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America
| | - Peter Makovicky
- Institute of Molecular Genetics of the Czech Academy of Sciences, Czech Centre for Phenogenomics, Vestec, Czech Republic
| | - Peter Sebo
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
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6
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Filipi K, Rahman WU, Osickova A, Osicka R. Kingella kingae RtxA Cytotoxin in the Context of Other RTX Toxins. Microorganisms 2022; 10:518. [PMID: 35336094 PMCID: PMC8953716 DOI: 10.3390/microorganisms10030518] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/22/2022] [Accepted: 02/24/2022] [Indexed: 12/04/2022] Open
Abstract
The Gram-negative bacterium Kingella kingae is part of the commensal oropharyngeal flora of young children. As detection methods have improved, K. kingae has been increasingly recognized as an emerging invasive pathogen that frequently causes skeletal system infections, bacteremia, and severe forms of infective endocarditis. K. kingae secretes an RtxA cytotoxin, which is involved in the development of clinical infection and belongs to an ever-growing family of cytolytic RTX (Repeats in ToXin) toxins secreted by Gram-negative pathogens. All RTX cytolysins share several characteristic structural features: (i) a hydrophobic pore-forming domain in the N-terminal part of the molecule; (ii) an acylated segment where the activation of the inactive protoxin to the toxin occurs by a co-expressed toxin-activating acyltransferase; (iii) a typical calcium-binding RTX domain in the C-terminal portion of the molecule with the characteristic glycine- and aspartate-rich nonapeptide repeats; and (iv) a C-proximal secretion signal recognized by the type I secretion system. RTX toxins, including RtxA from K. kingae, have been shown to act as highly efficient 'contact weapons' that penetrate and permeabilize host cell membranes and thus contribute to the pathogenesis of bacterial infections. RtxA was discovered relatively recently and the knowledge of its biological role remains limited. This review describes the structure and function of RtxA in the context of the most studied RTX toxins, the knowledge of which may contribute to a better understanding of the action of RtxA in the pathogenesis of K. kingae infections.
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Affiliation(s)
| | | | | | - Radim Osicka
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic; (K.F.); (W.U.R.); (A.O.)
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Belcher T, Dubois V, Rivera-Millot A, Locht C, Jacob-Dubuisson F. Pathogenicity and virulence of Bordetella pertussis and its adaptation to its strictly human host. Virulence 2021; 12:2608-2632. [PMID: 34590541 PMCID: PMC8489951 DOI: 10.1080/21505594.2021.1980987] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The highly contagious whooping cough agent Bordetella pertussis has evolved as a human-restricted pathogen from a progenitor which also gave rise to Bordetella parapertussis and Bordetella bronchiseptica. While the latter colonizes a broad range of mammals and is able to survive in the environment, B. pertussis has lost its ability to survive outside its host through massive genome decay. Instead, it has become a highly successful human pathogen by the acquisition of tightly regulated virulence factors and evolutionary adaptation of its metabolism to its particular niche. By the deployment of an arsenal of highly sophisticated virulence factors it overcomes many of the innate immune defenses. It also interferes with vaccine-induced adaptive immunity by various mechanisms. Here, we review data from invitro, human and animal models to illustrate the mechanisms of adaptation to the human respiratory tract and provide evidence of ongoing evolutionary adaptation as a highly successful human pathogen.
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Affiliation(s)
- Thomas Belcher
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Violaine Dubois
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Alex Rivera-Millot
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Camille Locht
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, Lille, France
| | - Françoise Jacob-Dubuisson
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, Lille, France
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8
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Pore-forming toxins in infection and immunity. Biochem Soc Trans 2021; 49:455-465. [PMID: 33492383 DOI: 10.1042/bst20200836] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 01/02/2021] [Accepted: 01/06/2021] [Indexed: 12/14/2022]
Abstract
The integrity of the plasma membranes is extremely crucial for the survival and proper functioning of the cells. Organisms from all kingdoms of life employ specialized pore-forming proteins and toxins (PFPs and PFTs) that perforate cell membranes, and cause detrimental effects. PFPs/PFTs exert their damaging actions by forming oligomeric pores in the membrane lipid bilayer. PFPs/PFTs play important roles in diverse biological processes. Many pathogenic bacteria secrete PFTs for executing their virulence mechanisms. The immune system of the higher vertebrates employs PFPs to kill pathogen-infected cells and transformed cancer cells. The most obvious consequence of membrane pore-formation by the PFPs/PFTs is the killing of the target cells due to the disruption of the permeability barrier function of the plasma membranes. PFPs/PFTs can also activate diverse cellular processes that include activation of the stress-response pathways, induction of programmed cell death, and inflammation. Upon attack by the PFTs, host cells may also activate pathways to repair the injured membranes, restore cellular homeostasis, and trigger inflammatory immune responses. In this article, we present an overview of the diverse cellular responses that are triggered by the PFPs/PFTs, and their implications in the process of pathogen infection and immunity.
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Tomala J, Spangler JB. Characterization of Immune Cell Subset Expansion in Response to Therapeutic Treatment in Mice. Methods Mol Biol 2020; 2111:101-114. [PMID: 31933202 DOI: 10.1007/978-1-0716-0266-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Flow cytometry has revolutionized the field of molecular immunology, enabling the monitoring and characterization of immune events at the single-cell level. Here, we describe a flow cytometry-based workflow to quantify the activation of specific immune cell subsets in mice in response to a molecular intervention. Compared to laborious long-term disease models, this technique allows for relatively rapid evaluation of candidate therapeutics designed to elicit a targeted immune response. This approach has the range to address both disease applications in which an immunostimulatory effect would be desired (e.g., cancer, infectious disease) or those in which an immunosuppressive effect would be desired (e.g., autoimmune disorders, transplantation medicine). Overall, our technique presents a powerful and accessible strategy for preliminary in vivo assessment of potential immunotherapeutics.
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Affiliation(s)
- Jakub Tomala
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jamie B Spangler
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA.
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA.
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Scanlon K, Skerry C, Carbonetti N. Role of Major Toxin Virulence Factors in Pertussis Infection and Disease Pathogenesis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1183:35-51. [PMID: 31376138 DOI: 10.1007/5584_2019_403] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Bordetella pertussis produces several toxins that affect host-pathogen interactions. Of these, the major toxins that contribute to pertussis infection and disease are pertussis toxin, adenylate cyclase toxin-hemolysin and tracheal cytotoxin. Pertussis toxin is a multi-subunit protein toxin that inhibits host G protein-coupled receptor signaling, causing a wide array of effects on the host. Adenylate cyclase toxin-hemolysin is a single polypeptide, containing an adenylate cyclase enzymatic domain coupled to a hemolysin domain, that primarily targets phagocytic cells to inhibit their antibacterial activities. Tracheal cytotoxin is a fragment of peptidoglycan released by B. pertussis that elicits damaging inflammatory responses in host cells. This chapter describes these three virulence factors of B. pertussis, summarizing background information and focusing on the role of each toxin in infection and disease pathogenesis, as well as their role in pertussis vaccination.
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Affiliation(s)
- Karen Scanlon
- Department of Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Ciaran Skerry
- Department of Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Nicholas Carbonetti
- Department of Microbiology & Immunology, University of Maryland School of Medicine, Baltimore, MD, USA.
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ATF4 Involvement in TLR4 and LOX-1-Induced Host Inflammatory Response to Aspergillus fumigatus Keratitis. J Ophthalmol 2018; 2018:5830202. [PMID: 30647960 PMCID: PMC6311808 DOI: 10.1155/2018/5830202] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 10/04/2018] [Accepted: 10/11/2018] [Indexed: 12/11/2022] Open
Abstract
Purpose Activating transcription factor 4 (ATF4) is induced by various stressors. Here, we investigated the expression of ATF4 in the host inflammatory response to Aspergillus fumigatus (A. fumigatus) keratitis. Methods A. fumigatus keratitis mouse models developed by intrastromal injection as well as corneal epithelium scratching were examined daily with a slit lamp microscope for corneal opacification and ulceration. Subsequent in vitro experimentation was carried out in human corneal epithelial cells (HCECs) as well as THP-1 macrophages infected with A. fumigatus. Inhibitors, including CLI-095, Poly (I), SCH772984, and SP600125, were used to assess the role of proteins like toll-like receptor 4 (TLR4), lectin-type oxidized LDL receptor 1 (LOX-1), extracellular signal-regulated kinases (ERK1/2), and c-Jun N-terminal kinase (JNK) in ATF4 expression as a response to A. fumigatus infection. This assessment was made in both mouse models and HCECs using western blot. Results Compared to the controls, ATF4 was increased in corneas from two kinds of A. fumigatus keratitis models at 3 days after infection. ATF4 expression was upregulated with A. fumigatus conidia both in HCECs and THP-1 macrophages 16 hours after stimulation. Furthermore, ATF4 expression in response to A. fumigatus infection was shown to be dependent on TLR4 and LOX-1 expression, and ERK1/2 and JNK contributed to the expression of ATF4 in response to A. fumigatus. Conclusion Our results clearly indicate that ATF4 was involved in the host antifungal immune response to A. fumigatus keratitis; expression was found to be dependent on TLR4, LOX-1 expression, and MAPKs pathway.
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12
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Voegele A, O'Brien DP, Subrini O, Sapay N, Cannella SE, Enguéné VYN, Hessel A, Karst J, Hourdel V, Perez ACS, Davi M, Veneziano R, Chopineau J, Vachette P, Durand D, Brier S, Ladant D, Chenal A. Translocation and calmodulin-activation of the adenylate cyclase toxin (CyaA) of Bordetella pertussis. Pathog Dis 2018; 76:5188676. [PMID: 30452651 DOI: 10.1093/femspd/fty085] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/16/2018] [Indexed: 01/19/2023] Open
Abstract
The adenylate cyclase toxin (CyaA) is a multi-domain protein secreted by Bordetella pertussis, the causative agent of whooping cough. CyaA is involved in the early stages of respiratory tract colonization by Bordetella pertussis. CyaA is produced and acylated in the bacteria, and secreted via a dedicated secretion system. The cell intoxication process involves a unique mechanism of transport of the CyaA toxin catalytic domain (ACD) across the plasma membrane of eukaryotic cells. Once translocated, ACD binds to and is activated by calmodulin and produces high amounts of cAMP, subverting the physiology of eukaryotic cells. Here, we review our work on the identification and characterization of a critical region of CyaA, the translocation region, required to deliver ACD into the cytosol of target cells. The translocation region contains a segment that exhibits membrane-active properties, i.e. is able to fold upon membrane interaction and permeabilize lipid bilayers. We proposed that this region is required to locally destabilize the membrane, decreasing the energy required for ACD translocation. To further study the translocation process, we developed a tethered bilayer lipid membrane (tBLM) design that recapitulate the ACD transport across a membrane separating two hermetic compartments. We showed that ACD translocation is critically dependent on calcium, membrane potential, CyaA acylation and on the presence of calmodulin in the trans compartment. Finally, we describe how calmodulin-binding triggers key conformational changes in ACD, leading to its activation and production of supraphysiological concentrations of cAMP.
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Affiliation(s)
- Alexis Voegele
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France.,Université Paris Diderot Paris VII, 75013 Paris, France
| | - Darragh P O'Brien
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France.,University of Oxford, United Kingdom
| | - Orso Subrini
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Nicolas Sapay
- Bioaster Technology Research Institute, 69007 Lyon, France
| | - Sara E Cannella
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France.,University of Oxford, United Kingdom
| | - Véronique Yvette Ntsogo Enguéné
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Audrey Hessel
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Johanna Karst
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Véronique Hourdel
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Ana Cristina Sotomayor Perez
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Marilyne Davi
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Rémi Veneziano
- ICGM, UMR 5253 Univ Montpellier, CNRS, ENSCM, Montpellier 34095, France.,Department of Bioengineering, Volgenau School of Engineering, George Mason University, Fairfax, VA 22030-4422, USA
| | - Joel Chopineau
- ICGM, UMR 5253 Univ Montpellier, CNRS, ENSCM, Montpellier 34095, France
| | - Patrice Vachette
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex 91198, France
| | - Dominique Durand
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex 91198, France
| | - Sébastien Brier
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Daniel Ladant
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
| | - Alexandre Chenal
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR 3528, 28 Rue du Dr Roux, 75724 Paris, CEDEX 15, France
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13
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Chenal A, Ladant D. Bioengineering of Bordetella pertussis Adenylate Cyclase Toxin for Antigen-Delivery and Immunotherapy. Toxins (Basel) 2018; 10:E302. [PMID: 30037010 PMCID: PMC6070788 DOI: 10.3390/toxins10070302] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 07/16/2018] [Accepted: 07/18/2018] [Indexed: 11/16/2022] Open
Abstract
The adenylate cyclase toxin (CyaA) is one of the major virulence factors of Bordetella pertussis, the causative agent of whooping cough. CyaA is able to invade eukaryotic cells where, upon activation by endogenous calmodulin, it synthesizes massive amounts of cAMP that alters cellular physiology. The CyaA toxin is a 1706 residues-long bifunctional protein: the catalytic domain is located in the 400 amino-proximal residues, whereas the carboxy-terminal 1306 residues are implicated in toxin binding to the cellular receptor, the αMβ₂ (CD11b/CD18) integrin, and subsequently in the translocation of the catalytic domain across the cytoplasmic membrane of the target cells. Indeed, this protein is endowed with the unique capability of delivering its N-terminal catalytic domain directly across the plasma membrane of eukaryotic target cells. These properties have been exploited to engineer the CyaA toxin as a potent non-replicating vector able to deliver antigens into antigen presenting cells and elicit specific cell-mediated immune responses. Antigens of interest can be inserted into the CyaA protein to yield recombinant molecules that are targeted in vivo to dendritic cells, where the antigens are processed and presented by the major class I and class II histocompatibility complexes (MHC-I and II). CyaA turned out to be a remarkably effective and versatile vaccine vector capable of inducing all the components of the immune response (T-CD4, T-CD8, and antibody). In this chapter, we summarize the basic knowledge on the adenylate cyclase toxin and then describe the application of CyaA in vaccinology, including some recent results of clinical trials of immunotherapy using a recombinant CyaA vaccine.
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Affiliation(s)
- Alexandre Chenal
- Institut Pasteur, Biochemistry of Macromolecular Interactions Unit, UMR CNRS 3528, Structural Biology and Chemistry Department, 28 rue du Docteur Roux, 75724 Paris CEDEX 15, France.
| | - Daniel Ladant
- Institut Pasteur, Biochemistry of Macromolecular Interactions Unit, UMR CNRS 3528, Structural Biology and Chemistry Department, 28 rue du Docteur Roux, 75724 Paris CEDEX 15, France.
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14
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Structure-Function Relationships Underlying the Capacity of Bordetella Adenylate Cyclase Toxin to Disarm Host Phagocytes. Toxins (Basel) 2017; 9:toxins9100300. [PMID: 28946636 PMCID: PMC5666347 DOI: 10.3390/toxins9100300] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 09/19/2017] [Accepted: 09/21/2017] [Indexed: 01/18/2023] Open
Abstract
Bordetellae, pathogenic to mammals, produce an immunomodulatory adenylate cyclase toxin-hemolysin (CyaA, ACT or AC-Hly) that enables them to overcome the innate immune defense of the host. CyaA subverts host phagocytic cells by an orchestrated action of its functional domains, where an extremely catalytically active adenylyl cyclase enzyme is delivered into phagocyte cytosol by a pore-forming repeat-in-toxin (RTX) cytolysin moiety. By targeting sentinel cells expressing the complement receptor 3, known as the CD11b/CD18 (αMβ₂) integrin, CyaA compromises the bactericidal functions of host phagocytes and supports infection of host airways by Bordetellae. Here, we review the state of knowledge on structural and functional aspects of CyaA toxin action, placing particular emphasis on signaling mechanisms by which the toxin-produced 3',5'-cyclic adenosine monophosphate (cAMP) subverts the physiology of phagocytic cells.
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15
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Invasion of Dendritic Cells, Macrophages and Neutrophils by the Bordetella Adenylate Cyclase Toxin: A Subversive Move to Fool Host Immunity. Toxins (Basel) 2017; 9:toxins9100293. [PMID: 28934122 PMCID: PMC5666340 DOI: 10.3390/toxins9100293] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 09/14/2017] [Accepted: 09/15/2017] [Indexed: 01/27/2023] Open
Abstract
Adenylate cyclase toxin (CyaA) is released in the course of B. pertussis infection in the host’s respiratory tract in order to suppress its early innate and subsequent adaptive immune defense. CD11b-expressing dendritic cells (DC), macrophages and neutrophils are professional phagocytes and key players of the innate immune system that provide a first line of defense against invading pathogens. Recent findings revealed the capacity of B. pertussis CyaA to intoxicate DC with high concentrations of 3′,5′-cyclic adenosine monophosphate (cAMP), which ultimately skews the host immune response towards the expansion of Th17 cells and regulatory T cells. CyaA-induced cAMP signaling swiftly incapacitates opsonophagocytosis, oxidative burst and NO-mediated killing of bacteria by neutrophils and macrophages. The subversion of host immune responses by CyaA after delivery into DC, macrophages and neutrophils is the subject of this review.
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16
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Cyclic AMP-Elevating Capacity of Adenylate Cyclase Toxin-Hemolysin Is Sufficient for Lung Infection but Not for Full Virulence of Bordetella pertussis. Infect Immun 2017; 85:IAI.00937-16. [PMID: 28396322 DOI: 10.1128/iai.00937-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 04/02/2017] [Indexed: 02/05/2023] Open
Abstract
The adenylate cyclase toxin-hemolysin (CyaA, ACT, or AC-Hly) of Bordetella pertussis targets phagocytic cells expressing the complement receptor 3 (CR3, Mac-1, αMβ2 integrin, or CD11b/CD18). CyaA delivers into cells an N-terminal adenylyl cyclase (AC) enzyme domain that is activated by cytosolic calmodulin and catalyzes unregulated conversion of cellular ATP into cyclic AMP (cAMP), a key second messenger subverting bactericidal activities of phagocytes. In parallel, the hemolysin (Hly) moiety of CyaA forms cation-selective hemolytic pores that permeabilize target cell membranes. We constructed the first B. pertussis mutant secreting a CyaA toxin having an intact capacity to deliver the AC enzyme into CD11b-expressing (CD11b+) host phagocytes but impaired in formation of cell-permeabilizing pores and defective in cAMP elevation in CD11b- cells. The nonhemolytic AC+ Hly- bacteria inhibited the antigen-presenting capacities of coincubated mouse dendritic cells in vitro and skewed their Toll-like receptor (TLR)-triggered maturation toward a tolerogenic phenotype. The AC+ Hly- mutant also infected mouse lungs as efficiently as the parental AC+ Hly+ strain. Hence, elevation of cAMP in CD11b- cells and/or the pore-forming capacity of CyaA were not required for infection of mouse airways. The latter activities were, however, involved in bacterial penetration across the epithelial layer, enhanced neutrophil influx into lung parenchyma during sublethal infections, and the exacerbated lung pathology and lethality of B. pertussis infections at higher inoculation doses (>107 CFU/mouse). The pore-forming activity of CyaA further synergized with the cAMP-elevating activity in downregulation of major histocompatibility complex class II (MHC-II) molecules on infiltrating myeloid cells, likely contributing to immune subversion of host defenses by the whooping cough agent.
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17
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Cerny O, Anderson KE, Stephens LR, Hawkins PT, Sebo P. cAMP Signaling of Adenylate Cyclase Toxin Blocks the Oxidative Burst of Neutrophils through Epac-Mediated Inhibition of Phospholipase C Activity. THE JOURNAL OF IMMUNOLOGY 2016; 198:1285-1296. [PMID: 28039302 DOI: 10.4049/jimmunol.1601309] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 11/16/2016] [Indexed: 01/08/2023]
Abstract
The adenylate cyclase toxin-hemolysin (CyaA) plays a key role in immune evasion and virulence of the whooping cough agent Bordetella pertussis. CyaA penetrates the complement receptor 3-expressing phagocytes and ablates their bactericidal capacities by catalyzing unregulated conversion of cytosolic ATP to the key second messenger molecule cAMP. We show that signaling of CyaA-generated cAMP blocks the oxidative burst capacity of neutrophils by two converging mechanisms. One involves cAMP/protein kinase A-mediated activation of the Src homology region 2 domain-containing phosphatase-1 (SHP-1) and limits the activation of MAPK ERK and p38 that are required for assembly of the NADPH oxidase complex. In parallel, activation of the exchange protein directly activated by cAMP (Epac) provokes inhibition of the phospholipase C by an as yet unknown mechanism. Indeed, selective activation of Epac by the cell-permeable analog 8-(4-chlorophenylthio)-2'-O-methyladenosine-3',5'-cyclic monophosphate counteracted the direct activation of phospholipase C by 2,4,6-trimethyl-N-[3-(trifluoromethyl)phenyl]benzenesulfonamide. Hence, by inhibiting production of the protein kinase C-activating lipid, diacylglycerol, cAMP/Epac signaling blocks the bottleneck step of the converging pathways of oxidative burst triggering. Manipulation of neutrophil membrane composition by CyaA-produced signaling of cAMP thus enables B. pertussis to evade the key innate host defense mechanism of reactive oxygen species-mediated killing of bacteria by neutrophils.
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Affiliation(s)
- Ondrej Cerny
- Laboratory of Molecular Biology of Bacterial Pathogens, Institute of Microbiology of the CAS, v.v.i., 142 20 Prague, Czech Republic; and
| | - Karen E Anderson
- Signalling Programme, Babraham Institute, Babraham, Cambridge CB22 3AT, United Kingdom
| | - Len R Stephens
- Signalling Programme, Babraham Institute, Babraham, Cambridge CB22 3AT, United Kingdom
| | - Phillip T Hawkins
- Signalling Programme, Babraham Institute, Babraham, Cambridge CB22 3AT, United Kingdom
| | - Peter Sebo
- Laboratory of Molecular Biology of Bacterial Pathogens, Institute of Microbiology of the CAS, v.v.i., 142 20 Prague, Czech Republic; and
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18
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Masin J, Osickova A, Sukova A, Fiser R, Halada P, Bumba L, Linhartova I, Osicka R, Sebo P. Negatively charged residues of the segment linking the enzyme and cytolysin moieties restrict the membrane-permeabilizing capacity of adenylate cyclase toxin. Sci Rep 2016; 6:29137. [PMID: 27581058 PMCID: PMC5007505 DOI: 10.1038/srep29137] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/15/2016] [Indexed: 11/10/2022] Open
Abstract
The whooping cough agent, Bordetella pertussis, secretes an adenylate cyclase toxin-hemolysin (CyaA) that plays a crucial role in host respiratory tract colonization. CyaA targets CR3-expressing cells and disrupts their bactericidal functions by delivering into their cytosol an adenylate cyclase enzyme that converts intracellular ATP to cAMP. In parallel, the hydrophobic domain of CyaA forms cation-selective pores that permeabilize cell membrane. The invasive AC and pore-forming domains of CyaA are linked by a segment that is unique in the RTX cytolysin family. We used mass spectrometry and circular dichroism to show that the linker segment forms α-helical structures that penetrate into lipid bilayer. Replacement of the positively charged arginine residues, proposed to be involved in target membrane destabilization by the linker segment, reduced the capacity of the toxin to translocate the AC domain across cell membrane. Substitutions of negatively charged residues then revealed that two clusters of negative charges within the linker segment control the size and the propensity of CyaA pore formation, thereby restricting the cell-permeabilizing capacity of CyaA. The ‘AC to Hly-linking segment’ thus appears to account for the smaller size and modest cell-permeabilizing capacity of CyaA pores, as compared to typical RTX hemolysins.
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Affiliation(s)
- Jiri Masin
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Adriana Osickova
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - Anna Sukova
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Radovan Fiser
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - Petr Halada
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Ladislav Bumba
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Irena Linhartova
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Radim Osicka
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Peter Sebo
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
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19
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Masin J, Osicka R, Bumba L, Sebo P. Bordetella adenylate cyclase toxin: a unique combination of a pore-forming moiety with a cell-invading adenylate cyclase enzyme. Pathog Dis 2015; 73:ftv075. [PMID: 26391732 DOI: 10.1093/femspd/ftv075] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2015] [Indexed: 12/30/2022] Open
Abstract
The adenylate cyclase toxin-hemolysin (CyaA, ACT or AC-Hly) is a key virulence factor of the whooping cough agent Bordetella pertussis. CyaA targets myeloid phagocytes expressing the complement receptor 3 (CR3, known as αMβ2 integrin CD11b/CD18 or Mac-1) and translocates by a poorly understood mechanism directly across the cytoplasmic membrane into cell cytosol of phagocytes an adenylyl cyclase(AC) enzyme. This binds intracellular calmodulin and catalyzes unregulated conversion of cytosolic ATP into cAMP. Among other effects, this yields activation of the tyrosine phosphatase SHP-1, BimEL accumulation and phagocyte apoptosis induction. In parallel, CyaA acts as a cytolysin that forms cation-selective pores in target membranes. Direct penetration of CyaA into the cytosol of professional antigen-presenting cells allows the use of an enzymatically inactive CyaA toxoid as a tool for delivery of passenger antigens into the cytosolic pathway of processing and MHC class I-restricted presentation, which can be exploited for induction of antigen-specific CD8(+) cytotoxic T-lymphocyte immune responses.
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Affiliation(s)
- Jiri Masin
- Laboratory of Molecular Biology of Bacterial Pathogens, Institute of Microbiology of the ASCR, v.v.i., Czech Academy of Sciences, 142 20, Prague 4, Czech Republic
| | - Radim Osicka
- Laboratory of Molecular Biology of Bacterial Pathogens, Institute of Microbiology of the ASCR, v.v.i., Czech Academy of Sciences, 142 20, Prague 4, Czech Republic
| | - Ladislav Bumba
- Laboratory of Molecular Biology of Bacterial Pathogens, Institute of Microbiology of the ASCR, v.v.i., Czech Academy of Sciences, 142 20, Prague 4, Czech Republic
| | - Peter Sebo
- Laboratory of Molecular Biology of Bacterial Pathogens, Institute of Microbiology of the ASCR, v.v.i., Czech Academy of Sciences, 142 20, Prague 4, Czech Republic
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