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Hale M, Takehara KK, Thouvenel CD, Moustafa DA, Repele A, Fontana MF, Netland J, McNamara S, Gibson RL, Goldberg JB, Rawlings DJ, Pepper M. Monoclonal antibodies derived from B cells in subjects with cystic fibrosis reduce Pseudomonas aeruginosa burden in mice. bioRxiv 2024:2024.04.08.588618. [PMID: 38645147 PMCID: PMC11030358 DOI: 10.1101/2024.04.08.588618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Pseudomonas aeruginosa (PA) is an opportunistic, frequently multidrug-resistant pathogen that can cause severe infections in hospitalized patients. Antibodies against the PA virulence factor, PcrV, protect from death and disease in a variety of animal models. However, clinical trials of PcrV-binding antibody-based products have thus far failed to demonstrate benefit. Prior candidates were derivations of antibodies identified using protein-immunized animal systems and required extensive engineering to optimize binding and/or reduce immunogenicity. Of note, PA infections are common in people with cystic fibrosis (pwCF), who are generally believed to mount normal adaptive immune responses. Here we utilized a tetramer reagent to detect and isolate PcrV-specific B cells in pwCF and, via single-cell sorting and paired-chain sequencing, identified the B cell receptor (BCR) variable region sequences that confer PcrV-specificity. We derived multiple high affinity anti-PcrV monoclonal antibodies (mAbs) from PcrV-specific B cells across 3 donors, including mAbs that exhibit potent anti-PA activity in a murine pneumonia model. This robust strategy for mAb discovery expands what is known about PA-specific B cells in pwCF and yields novel mAbs with potential for future clinical use.
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Simonis A, Kreer C, Albus A, Rox K, Yuan B, Holzmann D, Wilms JA, Zuber S, Kottege L, Winter S, Meyer M, Schmitt K, Gruell H, Theobald SJ, Hellmann AM, Meyer C, Ercanoglu MS, Cramer N, Munder A, Hallek M, Fätkenheuer G, Koch M, Seifert H, Rietschel E, Marlovits TC, van Koningsbruggen-Rietschel S, Klein F, Rybniker J. Discovery of highly neutralizing human antibodies targeting Pseudomonas aeruginosa. Cell 2023; 186:5098-5113.e19. [PMID: 37918395 DOI: 10.1016/j.cell.2023.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 07/17/2023] [Accepted: 10/02/2023] [Indexed: 11/04/2023]
Abstract
Drug-resistant Pseudomonas aeruginosa (PA) poses an emerging threat to human health with urgent need for alternative therapeutic approaches. Here, we deciphered the B cell and antibody response to the virulence-associated type III secretion system (T3SS) in a cohort of patients chronically infected with PA. Single-cell analytics revealed a diverse B cell receptor repertoire directed against the T3SS needle-tip protein PcrV, enabling the production of monoclonal antibodies (mAbs) abrogating T3SS-mediated cytotoxicity. Mechanistic studies involving cryoelectron microscopy identified a surface-exposed C-terminal PcrV epitope as the target of highly neutralizing mAbs with broad activity against drug-resistant PA isolates. These anti-PcrV mAbs were as effective as treatment with conventional antibiotics in vivo. Our study reveals that chronically infected patients represent a source of neutralizing antibodies, which can be exploited as therapeutics against PA.
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Affiliation(s)
- Alexander Simonis
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany; German Center for Infection Research (DZIF), partner site Bonn-Cologne, 50937 Cologne, Germany.
| | - Christoph Kreer
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Alexandra Albus
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Katharina Rox
- Department of Chemical Biology, Helmholtz Centre for Infection Research (HZI), 38124 Braunschweig, Germany; German Center for Infection Research (DZIF), partner site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Biao Yuan
- Institute of Structural and Systems Biology, University Medical Center Hamburg-Eppendorf (UKE), 22607 Hamburg, Germany; Centre for Structural Systems Biology (CSSB), 22607 Hamburg, Germany; Deutsches Elektronen-Synchrotron Zentrum (DESY), 22607 Hamburg, Germany
| | - Dmitriy Holzmann
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Joana A Wilms
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Sylvia Zuber
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Lisa Kottege
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Sandra Winter
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Meike Meyer
- CF Centre, Pediatric Pulmonology and Allergology, University Children's Hospital Cologne, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Centre for Rare Diseases, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
| | - Kristin Schmitt
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Henning Gruell
- Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany; Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Sebastian J Theobald
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Anna-Maria Hellmann
- Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany; Department of Experimental Pediatric Oncology, University Children's Hospital Cologne, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
| | - Christina Meyer
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Meryem Seda Ercanoglu
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Nina Cramer
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, 30625 Hannover, Germany
| | - Antje Munder
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, 30625 Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease (BREATH), German Center for Lung Research, 30625 Hannover, Germany
| | - Michael Hallek
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Gerd Fätkenheuer
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; German Center for Infection Research (DZIF), partner site Bonn-Cologne, 50937 Cologne, Germany
| | - Manuel Koch
- Institute for Dental Research and Oral Musculoskeletal Biology, Center for Biochemistry, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Harald Seifert
- German Center for Infection Research (DZIF), partner site Bonn-Cologne, 50937 Cologne, Germany; Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine and University Hospital of Cologne, University of Cologne, 50935 Cologne, Germany
| | - Ernst Rietschel
- CF Centre, Pediatric Pulmonology and Allergology, University Children's Hospital Cologne, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Centre for Rare Diseases, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
| | - Thomas C Marlovits
- Institute of Structural and Systems Biology, University Medical Center Hamburg-Eppendorf (UKE), 22607 Hamburg, Germany; Centre for Structural Systems Biology (CSSB), 22607 Hamburg, Germany; Deutsches Elektronen-Synchrotron Zentrum (DESY), 22607 Hamburg, Germany
| | - Silke van Koningsbruggen-Rietschel
- CF Centre, Pediatric Pulmonology and Allergology, University Children's Hospital Cologne, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Centre for Rare Diseases, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany
| | - Florian Klein
- Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany; German Center for Infection Research (DZIF), partner site Bonn-Cologne, 50937 Cologne, Germany; Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Jan Rybniker
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50937 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany; German Center for Infection Research (DZIF), partner site Bonn-Cologne, 50937 Cologne, Germany.
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Sabino YNV, Cotter PD, Mantovani HC. Anti-virulence compounds against Staphylococcus aureus associated with bovine mastitis: A new therapeutic option? Microbiol Res 2023; 271:127345. [PMID: 36889204 DOI: 10.1016/j.micres.2023.127345] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 02/22/2023] [Accepted: 02/26/2023] [Indexed: 03/05/2023]
Abstract
Bovine mastitis represents a major economic burden faced by the dairy industry. S. aureus is an important and prevalent bovine mastitis-associated pathogen in dairy farms worldwide. The pathogenicity and persistence of S. aureus in the bovine mammary gland are associated with the expression of a range of virulence factors involved in biofilm formation and the production of several toxins. The traditional therapeutic approach to treating bovine mastitis includes the use of antibiotics, but the emergence of antibiotic-resistant strains has caused therapeutic failure. New therapeutic approaches targeting virulence factors of S. aureus rather than cell viability can have several advantages including lower selective pressure towards the development of resistance and little impact on the host commensal microbiota. This review summarizes the potential of anti-virulence therapies to control S. aureus associated with bovine mastitis focusing on anti-toxin, anti-biofilm, and anti-quorum sensing compounds. It also points to potential sources of new anti-virulence inhibitors and presents screening strategies for identifying these compounds.
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Affiliation(s)
| | | | - Hilario C Mantovani
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, Madison, WI, USA.
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Dalesandro BE, Pires MM. Immunotargeting of Gram-Positive Pathogens via a Cell Wall Binding Tick Antifreeze Protein. J Med Chem 2023; 66:503-515. [PMID: 36563000 DOI: 10.1021/acs.jmedchem.2c01464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Immunological agents that supplement or modulate the host immune response have proven to have powerful therapeutic potential, although this modality is less explored against bacterial pathogens. We describe the application of a bacterial binding protein to re-engage the immune system toward pathogenic bacteria. More specifically, a hapten was conjugated to a protein expressed by Ixodes scapularis ticks, called I. scapularis antifreeze glycoprotein (IAFGP), that has high affinity for the d-alanine residue on the bacterial peptidoglycan. We showed that a fragment of this protein retained high surface binding affinity. Moreover, conjugation of a hapten to this peptide led to the display of haptens on the cell surface of vancomycin-resistant Enterococcus faecalis. Hapten display then induced the recruitment of antibodies and promoted uptake of bacterial pathogens by immune cells. These results demonstrate the feasibility in using cell wall binding agents as the basis of a class of bacterial immunotherapies.
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Affiliation(s)
- Brianna E Dalesandro
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Marcos M Pires
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
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5
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Liao C, Huang X, Wang Q, Yao D, Lu W. Virulence Factors of Pseudomonas Aeruginosa and Antivirulence Strategies to Combat Its Drug Resistance. Front Cell Infect Microbiol 2022; 12:926758. [PMID: 35873152 PMCID: PMC9299443 DOI: 10.3389/fcimb.2022.926758] [Citation(s) in RCA: 58] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 06/09/2022] [Indexed: 11/24/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen causing nosocomial infections in severely ill and immunocompromised patients. Ubiquitously disseminated in the environment, especially in hospitals, it has become a major threat to human health due to the constant emergence of drug-resistant strains. Multiple resistance mechanisms are exploited by P. aeruginosa, which usually result in chronic infections difficult to eradicate. Diverse virulence factors responsible for bacterial adhesion and colonization, host immune suppression, and immune escape, play important roles in the pathogenic process of P. aeruginosa. As such, antivirulence treatment that aims at reducing virulence while sparing the bacterium for its eventual elimination by the immune system, or combination therapies, has significant advantages over traditional antibiotic therapy, as the former imposes minimal selective pressure on P. aeruginosa, thus less likely to induce drug resistance. In this review, we will discuss the virulence factors of P. aeruginosa, their pathogenic roles, and recent advances in antivirulence drug discovery for the treatment of P. aeruginosa infections.
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Affiliation(s)
- Chongbing Liao
- Key Laboratory of Medical Molecular Virology (Ministry of Education (MOE)/National Health Commission (NHC)/Chinese Academy of Medical Sciences (CAMS)), School of Basic Medical Science, Fudan University, Shanghai, China
| | - Xin Huang
- Key Laboratory of Medical Molecular Virology (Ministry of Education (MOE)/National Health Commission (NHC)/Chinese Academy of Medical Sciences (CAMS)), School of Basic Medical Science, Fudan University, Shanghai, China
| | - Qingxia Wang
- Key Laboratory of Medical Molecular Virology (Ministry of Education (MOE)/National Health Commission (NHC)/Chinese Academy of Medical Sciences (CAMS)), School of Basic Medical Science, Fudan University, Shanghai, China
| | - Dan Yao
- Key Laboratory of Medical Molecular Virology (Ministry of Education (MOE)/National Health Commission (NHC)/Chinese Academy of Medical Sciences (CAMS)), School of Basic Medical Science, Fudan University, Shanghai, China
| | - Wuyuan Lu
- Key Laboratory of Medical Molecular Virology (Ministry of Education (MOE)/National Health Commission (NHC)/Chinese Academy of Medical Sciences (CAMS)), School of Basic Medical Science, Fudan University, Shanghai, China.,Shanghai Institute of Infectious Disease and Biosecurity, School of Public Health, Fudan University, Shanghai, China
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6
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Cahuzac H, Sallustrau A, Malgorn C, Beau F, Barbe P, Babin V, Dubois S, Palazzolo A, Thai R, Correia I, Lee KB, Garcia-Argote S, Lequin O, Keck M, Nozach H, Feuillastre S, Ge X, Pieters G, Audisio D, Devel L. Monitoring In Vivo Performances of Protein-Drug Conjugates Using Site-Selective Dual Radiolabeling and Ex Vivo Digital Imaging. J Med Chem 2022; 65:6953-6968. [PMID: 35500280 PMCID: PMC9833330 DOI: 10.1021/acs.jmedchem.2c00401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In preclinical models, the development and optimization of protein-drug conjugates require accurate determination of the plasma and tissue profiles of both the protein and its conjugated drug. To this aim, we developed a bioanalytical strategy based on dual radiolabeling and ex vivo digital imaging. By combining enzymatic and chemical reactions, we obtained homogeneous dual-labeled anti-MMP-14 Fabs (antigen-binding fragments) conjugated to monomethyl auristatin E where the protein scaffold was labeled with carbon-14 (14C) and the conjugated drug with tritium (3H). These antibody-drug conjugates with either a noncleavable or a cleavable linker were then evaluated in vivo. By combining liquid scintillation counting and ex vivo dual-isotope radio-imaging, it was possible not only to monitor both components simultaneously during their circulation phase but also to quantify accurately their amount accumulated within the different organs.
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Affiliation(s)
- Héloïse Cahuzac
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Antoine Sallustrau
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SCBM, 91191 Gif-sur-Yvette, (France)
| | - Carole Malgorn
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Fabrice Beau
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Peggy Barbe
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Victor Babin
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SCBM, 91191 Gif-sur-Yvette, (France)
| | - Steven Dubois
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Alberto Palazzolo
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SCBM, 91191 Gif-sur-Yvette, (France)
| | - Robert Thai
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Isabelle Correia
- Sorbonne Université, Ecole Normale Supérieure, PSL University, CNRS, Laboratoire des Biomolécules, LBM, 75005 Paris, France
| | - Ki Baek Lee
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston 1825 Pressler St, Houston TX 77030
| | - Sébastien Garcia-Argote
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SCBM, 91191 Gif-sur-Yvette, (France)
| | - Olivier Lequin
- Sorbonne Université, Ecole Normale Supérieure, PSL University, CNRS, Laboratoire des Biomolécules, LBM, 75005 Paris, France
| | - Mathilde Keck
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Hervé Nozach
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France)
| | - Sophie Feuillastre
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SCBM, 91191 Gif-sur-Yvette, (France)
| | - Xin Ge
- Institute of Molecular Medicine, University of Texas Health Science Center at Houston 1825 Pressler St, Houston TX 77030
| | - Gregory Pieters
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SCBM, 91191 Gif-sur-Yvette, (France)
| | - Davide Audisio
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SCBM, 91191 Gif-sur-Yvette, (France)
| | - Laurent Devel
- Université Paris-Saclay, CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, 91191 Gif-sur-Yvette, (France),
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Goldberg JB, Crisan CV, Luu JM. Pseudomonas aeruginosa Antivirulence Strategies: Targeting the Type III Secretion System. Adv Exp Med Biol 2022; 1386:257-280. [PMID: 36258075 DOI: 10.1007/978-3-031-08491-1_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The Pseudomonas aeruginosa type III secretion system (T3SS) is a complex molecular machine that delivers toxic proteins from the bacterial cytoplasm directly into host cells. This apparatus spans the inner and outer membrane and employs a needle-like structure that penetrates through the eucaryotic cell membrane into the host cell cytosol. The expression of the P. aeruginosa T3SS is highly regulated by environmental signals including low calcium and host cell contact. P. aeruginosa strains with mutations in T3SS genes are less pathogenic, suggesting that the T3SS is a virulence mechanism. Given that P. aeruginosa is naturally antibiotic resistant and multidrug resistant isolates are rapidly emerging, new antibiotics to target P. aeruginosa are needed. Furthermore, even if new antibiotics were to be developed, the timeline between when an antibiotic is released and resistance development is relatively short. Therefore, the concept of targeting virulence factors has garnered attention. So-called "antivirulence" approaches do not kill the microbe but instead focus on rendering it harmless and therefore unable to cause damage. Since these therapies target a particular system or pathway, the normal microbiome is unlikely to be affected and there is less concern about the spread to other microbes. Finally, and most importantly, since any antivirulence drug does not kill the microbe, there should be less selective pressure to develop resistance to these inhibitors. The P. aeruginosa T3SS has been well studied due to its importance for pathogenesis in numerous human and animal infections. Thus, many P. aeruginosa T3SS inhibitors have been described as potential antivirulence therapeutics, some of which have progressed to clinical trials.
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Affiliation(s)
- Joanna B Goldberg
- Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Department of Pediatrics and Children's Healthcare of Atlanta, Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, GA, USA.
| | - Cristian V Crisan
- Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Department of Pediatrics and Children's Healthcare of Atlanta, Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, GA, USA
| | - Justin M Luu
- Division of Pulmonary, Asthma, Cystic Fibrosis, and Sleep, Department of Pediatrics and Children's Healthcare of Atlanta, Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, GA, USA
- Microbiology and Molecular Genetics Program, Graduate Division of Biological and Biomedical Sciences, Laney Graduate School, Emory University, Atlanta, GA, USA
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Proctor LL, Ward WL, Roggy CS, Koontz AG, Clark KM, Quinn AP, Schroeder M, Brooks AE, Small JM, Towne FD, Brooks BD. Potential Therapeutic Targets for Combination Antibody Therapy against Pseudomonas aeruginosa Infections. Antibiotics (Basel) 2021; 10:1530. [PMID: 34943742 DOI: 10.3390/antibiotics10121530] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/03/2021] [Accepted: 12/09/2021] [Indexed: 12/12/2022] Open
Abstract
Despite advances in antimicrobial therapy and even the advent of some effective vaccines, Pseudomonas aeruginosa (P. aeruginosa) remains a significant cause of infectious disease, primarily due to antibiotic resistance. Although P. aeruginosa is commonly treatable with readily available therapeutics, these therapies are not always efficacious, particularly for certain classes of patients (e.g., cystic fibrosis (CF)) and for drug-resistant strains. Multi-drug resistant P. aeruginosa infections are listed on both the CDC’s and WHO’s list of serious worldwide threats. This increasing emergence of drug resistance and prevalence of P. aeruginosa highlights the need to identify new therapeutic strategies. Combinations of monoclonal antibodies against different targets and epitopes have demonstrated synergistic efficacy with each other as well as in combination with antimicrobial agents typically used to treat these infections. Such a strategy has reduced the ability of infectious agents to develop resistance. This manuscript details the development of potential therapeutic targets for polyclonal antibody therapies to combat the emergence of multidrug-resistant P. aeruginosa infections. In particular, potential drug targets for combinational immunotherapy against P. aeruginosa are identified to combat current and future drug resistance.
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Karam S, Raigani M, Hassani Afshar S, Talebkhan Y, Bayat E, Komijani S, Nematollahi L, Barkhordari F, Shafiee Ardestani M, Davami F. Production of an Antibody Fragment (scFv) Targeting PcrV Protein of Pseudomonas aeruginosa in Fed-Batch Cultivation Mode. Iran Biomed J 2021; 25:390-8. [PMID: 34641643 DOI: 10.52547/ibj.25.6.390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background: Pseudomonas aeruginosa is one of the opportunistic pathogens causing frequent hospital-acquired life-threatening infections in mechanically ventilated patients. The most significant virulence factor of P. aeruginosa is T3SS. PcrV is an important structural protein of the T3SS. Methods: In the current investigation, a recombinant scFv mAb against the PcrV protein was expressed in EnBase® (fed-batch) cultivation mode. The pETiteTM N-His SUMO Kan vector, including anti-PcrV scFv gene, was transformed into Escherichia coli (BL21) cells. The expression and solubility of anti-PcrV scFv protein were investigated at two different temperatures (25 °C and 30 °C) and at different induction times (4, 6, 8, 12, and 24 hours). Results: Increased efficiency was achieved by EnBase® compared to LB broth; owing to the slow release of glucose, the maximum level of solubility and total protein expression was observed in EnBase® cultivation system at 30 °C and 24 h post induction. Furthermore, IC50 for anti-PcrV scFv protein was determined to be approximately 7 μg/mL. Conclusion: Anti-PcrV scFv produced in this study showed promising in vitro results, protecting RBC from lysis by P. aeruginosa (exoU+).
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Zahedi Bialvaei A, Razavi S, Notash Haghighat F, Hemmati A, Akhavan MM, Jeddi-Tehrani M, Irajian G. Monoclonal antibody directed to the PilQ -PilA DSL region in Pseudomonas aeruginosa improves survival of infected mice with antibiotic combination. Microb Pathog 2021; 158:105060. [PMID: 34153421 DOI: 10.1016/j.micpath.2021.105060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/14/2021] [Accepted: 06/15/2021] [Indexed: 11/27/2022]
Abstract
The infections caused by Pseudomonas aeruginosa are related to high mortality and morbidity in critically ill patients because of multidrug resistance. Thus, we performed the efficacy of the monoclonal antibody (mAb) against PilQ -PilA DSL region (QA) in combination with antibiotics in a model of P. aeruginosa infection. In the present study, three clinically applicable antibiotics (levofloxacin, ceftazidime and gentamicin) and the anti-QA mAb were utilized for treatment of P. aeruginosa sepsis in mice. Reliably, in comparison with other treatment groups (antibody or antibiotic administration), the combination of antibiotic and anti-QA mAb essentially enhanced the survival of mice infected with P. aeruginosa PAO1. This synergistic effect was due to improved bactericidal effect, which prevented bacterial dissemination to different organs. Consequently, the antibiotic and anti-QA mAb combination gives a new effective strategy for the treatment of P. aeruginosa sepsis, particularly when large numbers of exceptionally virulent strains are present.
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Affiliation(s)
- Abed Zahedi Bialvaei
- Microbial Biotechnology Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Shabnam Razavi
- Microbial Biotechnology Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Farzaneh Notash Haghighat
- Monoclonal Antibody Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran
| | - Azam Hemmati
- Monoclonal Antibody Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran
| | | | - Mahmood Jeddi-Tehrani
- Monoclonal Antibody Research Center, Avicenna Research Institute, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran.
| | - Gholamreza Irajian
- Microbial Biotechnology Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran.
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11
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Abadir E, Silveira PA, Gasiorowski RE, Ramesh M, Romano A, Mekkawy AH, Lo TH, Kabani K, Sutherland S, Pietersz GA, Ho PJ, Bryant CE, Larsen SR, Clark GJ. Targeting CD300f to enhance hematopoietic stem cell transplantation in acute myeloid leukemia. Blood Adv 2020; 4:1206-16. [PMID: 32215656 DOI: 10.1182/bloodadvances.2019001289] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/19/2020] [Indexed: 12/11/2022] Open
Abstract
Allogeneic hematopoietic stem cell transplantation (allo-HSCT) significantly reduces the rate of relapse in acute myeloid leukemia (AML) but comes at the cost of significant treatment-related mortality. Despite the reduction in relapse overall, it remains common, especially in high-risk groups. The outcomes for patients who relapse after transplant remains very poor. A large proportion of the morbidity that prevents most patients from accessing allo-HSCT is due to toxic nonspecific conditioning agents that are required to remove recipient hematopoietic stem and progenitor cells (HSPCs), allowing for successful donor engraftment. CD300f is expressed evenly across HSPC subtypes. CD300f has transcription and protein expression equivalent to CD33 on AML. We have developed an anti-CD300f antibody that efficiently internalizes into target cells. We have generated a highly potent anti-CD300f antibody-drug conjugate (ADC) with a pyrrolobenzodiazepine warhead that selectively depletes AML cell lines and colony forming units in vitro. The ADC synergizes with fludarabine, making it a natural combination to use in a minimal toxicity conditioning regimen. Our ADC prolongs the survival of mice engrafted with human cell lines and depletes primary human AML engrafted with a single injection. In a humanized mouse model, a single injection of the ADC depletes CD34+ HSPCs and CD34+CD38-CD90+ hematopoietic stem cells. This work establishes an anti-CD300f ADC as an attractive potential therapeutic that, if validated in transplant models using a larger cohort of primary AML samples, will reduce relapse rate and toxicity for patients with AML undergoing allo-HSCT.
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12
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Moir DT, Opperman TJ, Aron ZD, Bowlin TL. Adjunctive therapy for multidrug-resistant bacterial infections: Type III secretion system and efflux inhibitors. Drug Discov Today 2021; 26:2173-2181. [PMID: 33845218 DOI: 10.1016/j.drudis.2021.03.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/21/2021] [Accepted: 03/31/2021] [Indexed: 10/21/2022]
Abstract
The increasing prevalence of multidrug-resistant (MDR) bacterial infections has created a crucial need for new therapeutics that avoid or minimize existing resistance mechanisms. In this review, we describe the development of novel classes of small-molecule adjunctive agents targeting either a bacterial virulence factor, the Pseudomonas aeruginosa type III secretion system (T3SS), or an intrinsic resistance factor, resistance-nodulation-cell division superfamily (RND) efflux pumps of the Enterobacteriaceae. These agents are designed to be administered with antibacterials to improve their efficacy. T3SS inhibition rescues host innate immune system cells from injection with bacterial toxins, whereas RND efflux pump inhibition increases antibiotic susceptibility, in both cases improving the efficacy of the combined antibacterial.
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13
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Komijani S, Bayat E, Rismani E, Hosseini S, Moazzami R, Nematollahi L, Sardari S, Talebkhan Y, Davami F, Barkhordari F, Hosseini F, Jahandar H. Characterization of a novel mCH3 conjugated anti-PcrV scFv molecule. Sci Rep 2021; 11:7154. [PMID: 33785781 DOI: 10.1038/s41598-021-86491-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 03/16/2021] [Indexed: 11/25/2022] Open
Abstract
Pseudomonas aeruginosa (PA) is a leading cause of nosocomial infections and death in cystic fibrosis patients. The study was conducted to evaluate the physicochemical structure, biological activity and serum stability of a recombinant anti-PcrV single chain variable antibody fragment genetically attached to the mCH3cc domain. The stereochemical properties of scFv-mCH3 (YFL001) and scFv (YFL002) proteins as well as molecular interactions towards Pseudomonas aeruginosa PcrV were evaluated computationally. The subcloned fragments encoding YFL001 and YFL002 in pET28a were expressed within the E. coli BL21-DE3 strain. After Ni–NTA affinity chromatography, the biological activity of the proteins in inhibition of PA induced hemolysis as well as cellular cytotoxicity was assessed. In silico analysis revealed the satisfactory stereochemical quality of the models as well as common residues in their interface with PcrV. The structural differences of proteins through circular dichroism spectroscopy were confirmed by NMR analysis. Both proteins indicated inhibition of ExoU positive PA strains in hemolysis of red blood cells compared to ExoU negative strains as well as cytotoxicity effect on lung epithelial cells. The ELISA test showed the longer serum stability of the YFL001 molecule than YFL002. The results were encouraging to further evaluation of these two scFv molecules in animal models.
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14
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Moir DT, Bowlin NO, Berube BJ, Yabut J, Mills DM, Nguyen GT, Aron ZD, Williams JD, Mecsas J, Hauser AR, Bowlin TL. A Structure-Function-Inhibition Analysis of the Pseudomonas aeruginosa Type III Secretion Needle Protein PscF. J Bacteriol 2020; 202:e00055-20. [PMID: 32601072 PMCID: PMC7925083 DOI: 10.1128/jb.00055-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 06/19/2020] [Indexed: 01/10/2023] Open
Abstract
The Pseudomonas aeruginosa type III secretion system (T3SS) needle comprised of multiple PscF subunits is essential for the translocation of effector toxins into human cells, facilitating the establishment and dissemination of infection. Mutations in the pscF gene provide resistance to the phenoxyacetamide (PhA) series of T3SS inhibitory chemical probes. To better understand PscF functions and interactions with PhA, alleles of pscF with 71 single mutations altering 49 of the 85 residues of the encoded protein were evaluated for their effects on T3SS phenotypes. Of these, 37% eliminated and 63% maintained secretion, with representatives of both evenly distributed across the entire protein. Mutations in 14 codons conferred a degree of PhA resistance without eliminating secretion, and all but one were in the alpha-helical C-terminal 25% of PscF. PhA-resistant mutants exhibited no cross-resistance to two T3SS inhibitors with different chemical scaffolds. Two mutations caused constitutive T3SS secretion. The pscF allele at its native locus, whether wild type (WT), constitutive, or PhA resistant, was dominant over other pscF alleles expressed from nonnative loci and promoters, but mixed phenotypes were observed in chromosomal ΔpscF strains with both WT and mutant alleles at nonnative loci. Some PhA-resistant mutants exhibited reduced translocation efficiency that was improved in a PhA dose-dependent manner, suggesting that PhA can bind to those resistant needles. In summary, these results are consistent with a direct interaction between PhA inhibitors and the T3SS needle, suggest a mechanism of blocking conformational changes, and demonstrate that PscF affects T3SS regulation, as well as carrying out secretion and translocation.IMPORTANCEP. aeruginosa effector toxin translocation into host innate immune cells is critical for the establishment and dissemination of P. aeruginosa infections. The medical need for new anti-P. aeruginosa agents is evident by the fact that P. aeruginosa ventilator-associated pneumonia is associated with a high mortality rate (40 to 69%) and recurs in >30% of patients, even with standard-of-care antibiotic therapy. The results described here confirm roles for the PscF needle in T3SS secretion and translocation and suggest that it affects regulation, possibly by interaction with T3SS regulatory proteins. The results also support a model of direct interaction of the needle with PhA and suggest that, with further development, members of the PhA series may prove useful as drugs for P. aeruginosa infection.
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Affiliation(s)
| | | | - Bryan J Berube
- Department of Microbiology and Immunology, Northwestern University, Chicago, Illinois, USA
- Department of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Jaden Yabut
- Microbiotix, Inc., Worcester, Massachusetts, USA
| | | | - Giang T Nguyen
- Tufts Graduate School in Biomedical Sciences, Tufts University School of Medicine, Boston, Massachusetts, USA
| | | | | | - Joan Mecsas
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Alan R Hauser
- Department of Microbiology and Immunology, Northwestern University, Chicago, Illinois, USA
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Abstract
Despite ongoing efforts, a highly effective vaccine against Plasmodium falciparum remains elusive. Vaccines targeting the pre-erythrocytic stages of the P. falciparum life cycle are the most advanced to date, affording moderate levels of efficacy in field trials. However, the discovery that the members of the merozoite PfRH5-PfCyRPA-PfRipr (RCR) complex are capable of inducing strain-transcendent neutralizing antibodies has renewed enthusiasm for the possibility of preventing disease by targeting the parasite during the blood stage of infection. With Phase I/II clinical trials now underway using first-generation vaccines against PfRH5, and more on the horizon for PfCyRPA and PfRipr, this review explores the rationale and future potential of the RCR complex as a P. falciparum vaccine target.
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Affiliation(s)
- Robert J Ragotte
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK.
| | - Matthew K Higgins
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Simon J Draper
- The Jenner Institute, University of Oxford, Oxford, OX3 7DQ, UK.
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16
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Zurawski DV, McLendon MK. Monoclonal Antibodies as an Antibacterial Approach Against Bacterial Pathogens. Antibiotics (Basel) 2020; 9:antibiotics9040155. [PMID: 32244733 PMCID: PMC7235762 DOI: 10.3390/antibiotics9040155] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 03/14/2020] [Accepted: 03/16/2020] [Indexed: 12/11/2022] Open
Abstract
In the beginning of the 21st century, the frequency of antimicrobial resistance (AMR) has reached an apex, where even 4th and 5th generation antibiotics are becoming useless in clinical settings. In turn, patients are suffering from once-curable infections, with increases in morbidity and mortality. The root cause of many of these infections are the ESKAPEE pathogens (Enterococcus species, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species, and Escherichia coli), which thrive in the nosocomial environment and are the bacterial species that have seen the largest rise in the acquisition of antibiotic resistance genes. While traditional small-molecule development still dominates the antibacterial landscape for solutions to AMR, some researchers are now turning to biological approaches as potential game changers. Monoclonal antibodies (mAbs)—more specifically, human monoclonal antibodies (Hu-mAbs)—have been highly pursued in the anti-cancer, autoimmune, and antiviral fields with many success stories, but antibody development for bacterial infection is still just scratching the surface. The untapped potential for Hu-mAbs to be used as a prophylactic or therapeutic treatment for bacterial infection is exciting, as these biologics do not have the same toxicity hurdles of small molecules, could have less resistance as they often target virulence proteins rather than proteins required for survival, and are narrow spectrum (targeting just one pathogenic species), therefore avoiding the disruption of the microbiome. This mini-review will highlight the current antibacterial mAbs approved for patient use, the success stories for mAb development, and new Hu-mAb products in the antibacterial pipeline.
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17
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Kinoshita M, Shimizu M, Akiyama K, Kato H, Moriyama K, Sawa T. Epidemiological survey of serum titers from adults against various Gram-negative bacterial V-antigens. PLoS One 2020; 15:e0220924. [PMID: 32155175 PMCID: PMC7064248 DOI: 10.1371/journal.pone.0220924] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 02/24/2020] [Indexed: 11/18/2022] Open
Abstract
The V-antigen, a virulence-associated protein, was first identified in Yersinia pestis more than half a century ago. Since then, other V-antigen homologs and orthologs have been discovered and are now considered as critical molecules for the toxic effects mediated by the type III secretion system during infections caused by various pathogenic Gram-negative bacteria. After purifying recombinant V-antigen proteins, including PcrV from Pseudomonas aeruginosa, LcrV from Yersinia, LssV from Photorhabdus luminescens, AcrV from Aeromonas salmonicida, and VcrV from Vibrio parahaemolyticus, we developed an enzyme-linked immunoabsorbent assay to measure titers against each V-antigen in sera collected from 186 adult volunteers. Different titer-specific correlation levels were determined for the five V-antigens. The anti-LcrV and anti-AcrV titers shared the highest correlation with each other with a correlation coefficient of 0.84. The next highest correlation coefficient was between anti-AcrV and anti-VcrV titers at 0.79, while the lowest correlation was found between anti-LcrV and anti-VcrV titers, which were still higher than 0.7. Sera from mice immunized with one of the five recombinant V-antigens displayed cross-antigenicity with some of the other four V-antigens, supporting the results from the human sera. Thus, the serum anti-V-antigen titer measurement system may be used for epidemiological investigations of various pathogenic Gram-negative bacteria.
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Affiliation(s)
- Mao Kinoshita
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Masaru Shimizu
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Koichi Akiyama
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hideya Kato
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Kiyoshi Moriyama
- Department of Anesthesiology, School of Medicine, Kyorin University, Tokyo, Japan
| | - Teiji Sawa
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
- * E-mail:
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18
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Sundin C, Zetterström CE, Vo DD, Brkljača R, Urban S, Elofsson M. Exploring resveratrol dimers as virulence blocking agents - Attenuation of type III secretion in Yersinia pseudotuberculosis and Pseudomonas aeruginosa. Sci Rep 2020; 10:2103. [PMID: 32034212 DOI: 10.1038/s41598-020-58872-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 01/20/2020] [Indexed: 12/25/2022] Open
Abstract
Bacterial infections continue to threaten humankind and the rapid spread of antibiotic resistant bacteria is alarming. Current antibiotics target essential bacterial processes and thereby apply a strong selective pressure on pathogenic and non-pathogenic bacteria alike. One alternative strategy is to block bacterial virulence systems that are essential for the ability to cause disease but not for general bacterial viability. We have previously show that the plant natural product (-)-hopeaphenol blocks the type III secretion system (T3SS) in the Gram-negative pathogens Yersinia pseudotuberculosis and Pseudomonas aeruginosa. (-)-Hopeaphenol is a resveratrol tetramer and in the present study we explore various resveratrol dimers, including partial structures of (-)-hopeaphenol, as T3SS inhibitors. To allow rapid and efficient assessment of T3SS inhibition in P. aeruginosa, we developed a new screening method by using a green fluorescent protein reporter under the control of the ExoS promoter. Using a panel of assays we showed that compounds with a benzofuran core structure i.e. viniferifuran, dehydroampelopsin B, anigopreissin A, dehydro-δ-viniferin and resveratrol-piceatannol hybrid displayed significant to moderate activities towards the T3SS in Y. pseudotuberculosis and P. aeruginosa.
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Sawa T, Kinoshita M, Inoue K, Ohara J, Moriyama K. Immunoglobulin for Treating Bacterial Infections: One More Mechanism of Action. Antibodies (Basel) 2019; 8:antib8040052. [PMID: 31684203 PMCID: PMC6963986 DOI: 10.3390/antib8040052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 10/17/2019] [Accepted: 10/28/2019] [Indexed: 02/08/2023] Open
Abstract
The mechanisms underlying the effects of immunoglobulins on bacterial infections are thought to involve bacterial cell lysis via complement activation, phagocytosis via bacterial opsonization, toxin neutralization, and antibody-dependent cell-mediated cytotoxicity. Nevertheless, recent advances in the study of the pathogenicity of Gram-negative bacteria have raised the possibility of an association between immunoglobulin and bacterial toxin secretion. Over time, new toxin secretion systems like the type III secretion system have been discovered in many pathogenic Gram-negative bacteria. With this system, the bacterial toxins are directly injected into the cytoplasm of the target cell through a special secretory apparatus without any exposure to the extracellular environment, and therefore with no opportunity for antibodies to neutralize the toxin. However, antibodies against the V-antigen, which is located on the needle-shaped tip of the bacterial secretion apparatus, can inhibit toxin translocation, thus raising the hope that the toxin may be susceptible to antibody targeting. Because multi-drug resistant bacteria are now prevalent, inhibiting this secretion mechanism is an attractive alternative or adjunctive therapy against lethal bacterial infections. Thus, it is not unreasonable to define the blocking effect of anti-V-antigen antibodies as the fifth mechanism for immunoglobulin action against bacterial infections.
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Affiliation(s)
- Teiji Sawa
- Department of Anesthesiology, School of Medicine, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
| | - Mao Kinoshita
- Department of Anesthesiology, School of Medicine, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
| | - Keita Inoue
- Department of Anesthesiology, School of Medicine, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
| | - Junya Ohara
- Department of Anesthesiology, School of Medicine, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
| | - Kiyoshi Moriyama
- Department of Anesthesiology, Kyorin University School of Medicine, Tokyo 181-8611, Japan.
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Ranjbar M, Behrouz B, Norouzi F, Mousavi Gargari SL. Anti-PcrV IgY antibodies protect against Pseudomonas aeruginosa infection in both acute pneumonia and burn wound models. Mol Immunol 2019; 116:98-105. [PMID: 31634816 DOI: 10.1016/j.molimm.2019.10.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 10/04/2019] [Accepted: 10/07/2019] [Indexed: 12/11/2022]
Abstract
Pseudomonas aeruginosa is a common nosocomial pathogen in burn patients, and rapidly acquires antibiotic resistance; thus, developing an effective therapeutic approach is the most promising strategy for combating infection. Type III secretion system (T3SS) translocates bacterial toxins into the cytosol of the targeted eukaryotic cells, which plays important roles in the virulence of P. aeruginosa infections in both acute pneumonia and burn wound models. The PcrV protein, a T3SS translocating protein, is required for T3SS function and is a well-validated target in animal models of immunoprophylactic strategies targeting P. aeruginosa. In the present study, we evaluated the protective efficacy of chicken egg yolk antibodies (IgY) raised against recombinant PcrV (r-PcrV) in both acute pneumonia and burn wound models. R-PcrV protein was generated by expressing the pcrV gene (cloned in pET-28a vector) in E. coli BL-21. Anti-PcrV IgY was obtained by immunization of hen. Anti-PcrV IgY induced greater protection in P. aeruginosamurine acute pneumonia and burn wound models than control IgY (C-IgY) and PBS groups. Anti-PcrV IgY improved opsonophagocytic killing and inhibition of bacterial invasion of host cells. Taken together, our data provide evidence that anti-PcrV IgY can be a promising therapeutic candidate for combating P. aeruginosa infections.
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Affiliation(s)
- Mahya Ranjbar
- Department of Microbiology, Shahed University, Faculty of Medical Sciences, Tehran, Iran; Department of Biology, Faculty of Basic Science, Shahed University, Tehran, Iran
| | - Bahador Behrouz
- Department of Biology, Faculty of Basic Science, Shahed University, Tehran, Iran
| | - Fatemeh Norouzi
- Department of Biology, Faculty of Basic Science, Shahed University, Tehran, Iran
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Horcajada JP, Montero M, Oliver A, Sorlí L, Luque S, Gómez-Zorrilla S, Benito N, Grau S. Epidemiology and Treatment of Multidrug-Resistant and Extensively Drug-Resistant Pseudomonas aeruginosa Infections. Clin Microbiol Rev 2019; 32:32/4/e00031-19. [PMID: 31462403 PMCID: PMC6730496 DOI: 10.1128/cmr.00031-19] [Citation(s) in RCA: 401] [Impact Index Per Article: 80.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
In recent years, the worldwide spread of the so-called high-risk clones of multidrug-resistant or extensively drug-resistant (MDR/XDR) Pseudomonas aeruginosa has become a public health threat. This article reviews their mechanisms of resistance, epidemiology, and clinical impact and current and upcoming therapeutic options. In vitro and in vivo treatment studies and pharmacokinetic and pharmacodynamic (PK/PD) models are discussed. Polymyxins are reviewed as an important therapeutic option, outlining dosage, pharmacokinetics and pharmacodynamics, and their clinical efficacy against MDR/XDR P. aeruginosa infections. Their narrow therapeutic window and potential for combination therapy are also discussed. Other "old" antimicrobials, such as certain β-lactams, aminoglycosides, and fosfomycin, are reviewed here. New antipseudomonals, as well as those in the pipeline, are also reviewed. Ceftolozane-tazobactam has clinical activity against a significant percentage of MDR/XDR P. aeruginosa strains, and its microbiological and clinical data, as well as recommendations for improving its use against these bacteria, are described, as are those for ceftazidime-avibactam, which has better activity against MDR/XDR P. aeruginosa, especially strains with certain specific mechanisms of resistance. A section is devoted to reviewing upcoming active drugs such as imipenem-relebactam, cefepime-zidebactam, cefiderocol, and murepavadin. Finally, other therapeutic strategies, such as use of vaccines, antibodies, bacteriocins, anti-quorum sensing, and bacteriophages, are described as future options.
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Affiliation(s)
- Juan P Horcajada
- Service of Infectious Diseases, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Autònoma de Barcelona, Barcelona, Spain
- Spanish Network for Research in Infectious Diseases (REIPI), Madrid, Spain
| | - Milagro Montero
- Service of Infectious Diseases, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Autònoma de Barcelona, Barcelona, Spain
- Spanish Network for Research in Infectious Diseases (REIPI), Madrid, Spain
| | - Antonio Oliver
- Service of Microbiology, Hospital Son Espases, Instituto de Investigación Sanitaria Illes Balears (IdISBa), Palma de Mallorca, Spain
| | - Luisa Sorlí
- Service of Infectious Diseases, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Pompeu Fabra, Barcelona, Spain
- Spanish Network for Research in Infectious Diseases (REIPI), Madrid, Spain
| | - Sònia Luque
- Service of Pharmacy, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Silvia Gómez-Zorrilla
- Service of Infectious Diseases, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Pompeu Fabra, Barcelona, Spain
- Spanish Network for Research in Infectious Diseases (REIPI), Madrid, Spain
| | - Natividad Benito
- Infectious Diseases Unit, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomèdica Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Santiago Grau
- Service of Pharmacy, Hospital del Mar, Infectious Pathology and Antimicrobials Research Group, Institut Hospital del Mar d'Investigacions Mèdiques (IMIM), Universitat Autònoma de Barcelona, Barcelona, Spain
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22
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Feng C, Huang Y, He W, Cheng X, Liu H, Huang Y, Ma B, Zhang W, Liao C, Wu W, Shao Y, Xu D, Su Z, Lu W. Tanshinones: First-in-Class Inhibitors of the Biogenesis of the Type 3 Secretion System Needle of Pseudomonas aeruginosa for Antibiotic Therapy. ACS Cent Sci 2019; 5:1278-1288. [PMID: 31403076 PMCID: PMC6662154 DOI: 10.1021/acscentsci.9b00452] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Indexed: 05/17/2023]
Abstract
The type 3 secretion system (T3SS) found as cell-surface appendages of many pathogenic Gram-negative bacteria, although nonessential for bacterial survival, is an important therapeutic target for drug discovery and development aimed at inhibiting bacterial virulence without inducing antibiotic resistance. We designed a fluorescence-polarization-based assay for high-throughput screening as a mechanistically well-defined general strategy for antibiotic discovery targeting the T3SS and made a serendipitous discovery of a subset of tanshinones-natural herbal compounds in traditional Chinese medicine widely used for the treatment of cardiovascular and cerebrovascular diseases-as effective inhibitors of the biogenesis of the T3SS needle of multi-drug-resistant Pseudomonas aeruginosa. By inhibiting the T3SS needle assembly and, thus, cytotoxicity and pathogenicity, selected tanshinones reduced the secretion of bacterial virulence factors toxic to macrophages in vitro, and rescued experimental animals challenged with lethal doses of Pseudomonas aeruginosa in a murine model of acute pneumonia. As first-in-class inhibitors with a demonstrable safety profile in humans, tanshinones may be used directly to alleviate Pseudomonas-aeruginosa-associated pulmonary infections without inducing antibiotic resistance. Since the T3SS is highly conserved among Gram-negative bacteria, this antivirulence strategy may be applicable to the discovery and development of novel classes of antibiotics refractory to existing resistance mechanisms for the treatment of many bacterial infections.
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Affiliation(s)
- Chao Feng
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Yinong Huang
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Wangxiao He
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Xiyao Cheng
- Department
of Biological and Food Engineering, Hubei
University of Technology, Wuhan 430068, China
| | - Huili Liu
- State
Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese
Academy of Sciences, Wuhan 430071, China
| | - Yongqi Huang
- Department
of Biological and Food Engineering, Hubei
University of Technology, Wuhan 430068, China
| | - Bohan Ma
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Wei Zhang
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Chongbing Liao
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Weihui Wu
- State Key
Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular
Microbiology and Technology of the Ministry of Education, Department
of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yongping Shao
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Dan Xu
- Center
for Translational Medicine, Frontier Institute of Science
and Technology, Shaanxi Institute of Pediatric Diseases, Affiliated Children’s
Hospital, and Key Laboratory of Biomedical Information Engineering of the Ministry
of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710054, China
| | - Zhengding Su
- Department
of Biological and Food Engineering, Hubei
University of Technology, Wuhan 430068, China
| | - Wuyuan Lu
- Institute
of Human Virology and Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201, United States
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Abstract
Ventilator-associated pneumonia (VAP) is one of the most prevalent and serious complications of mechanical ventilation, which is considered a common nosocomial infection in critically ill patients. There are some great options for the prevention of VAP: (i) minimize ventilator exposure; (ii) intensive oral care; (iii) aspiration of subglottic secretions; (iv) maintain optimal positioning and encourage mobility; and (v) prophylactic probiotics. Furthermore, clinical management of VAP depends on appropriate antimicrobial therapy, which needs to be selected based on individual patient factors, such as previous antibacterial therapy, history of hospitalization or mechanical ventilation, and bacterial pathogens and antibiotic resistance patterns. In fact, antibiotic resistance has exponentially increased over the last decade, and the isolation of a multidrug-resistant (MDR) pathogen has been identified as an independent predictor of inadequate initial antibiotic therapy and which is significantly associated with increased mortality. Multiple attempts were used in the treatment of VAP, such as novel antibacterial agents, inhaled antibiotics and monoclonal antibodies. In this review, we summarize the current therapeutic options for the prevention and treatment of VAP, aiming to better management of VAP in clinical practice.
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Affiliation(s)
- Xinming Xie
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Jun Lyu
- Clinical Research Center, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Tafseel Hussain
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
| | - Manxiang Li
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an, China
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24
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Monserrat-Martinez A, Gambin Y, Sierecki E. Thinking Outside the Bug: Molecular Targets and Strategies to Overcome Antibiotic Resistance. Int J Mol Sci 2019; 20:ijms20061255. [PMID: 30871132 PMCID: PMC6470534 DOI: 10.3390/ijms20061255] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 03/04/2019] [Accepted: 03/04/2019] [Indexed: 12/25/2022] Open
Abstract
Since their discovery in the early 20th century, antibiotics have been used as the primary weapon against bacterial infections. Due to their prophylactic effect, they are also used as part of the cocktail of drugs given to treat complex diseases such as cancer or during surgery, in order to prevent infection. This has resulted in a decrease of mortality from infectious diseases and an increase in life expectancy in the last 100 years. However, as a consequence of administering antibiotics broadly to the population and sometimes misusing them, antibiotic-resistant bacteria have appeared. The emergence of resistant strains is a global health threat to humanity. Highly-resistant bacteria like Staphylococcus aureus (methicillin-resistant) or Enterococcus faecium (vancomycin-resistant) have led to complications in intensive care units, increasing medical costs and putting patient lives at risk. The appearance of these resistant strains together with the difficulty in finding new antimicrobials has alarmed the scientific community. Most of the strategies currently employed to develop new antibiotics point towards novel approaches for drug design based on prodrugs or rational design of new molecules. However, targeting crucial bacterial processes by these means will keep creating evolutionary pressure towards drug resistance. In this review, we discuss antibiotic resistance and new options for antibiotic discovery, focusing in particular on new alternatives aiming to disarm the bacteria or empower the host to avoid disease onset.
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Affiliation(s)
- Ana Monserrat-Martinez
- European Molecular Biology Laboratory Australia (EMBL Australia) Node in Single Molecule Science, Sydney, NSW 2031, Australia.
- School of Medical Sciences, The University of New South Wales, Sydney, NSW 2031, Australia.
| | - Yann Gambin
- European Molecular Biology Laboratory Australia (EMBL Australia) Node in Single Molecule Science, Sydney, NSW 2031, Australia.
- School of Medical Sciences, The University of New South Wales, Sydney, NSW 2031, Australia.
| | - Emma Sierecki
- European Molecular Biology Laboratory Australia (EMBL Australia) Node in Single Molecule Science, Sydney, NSW 2031, Australia.
- School of Medical Sciences, The University of New South Wales, Sydney, NSW 2031, Australia.
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25
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Naito Y, Hamaoka S, Kinoshita M, Kainuma A, Shimizu M, Katoh H, Moriyama K, Ishii KJ, Sawa T. The protective effects of nasal PcrV-CpG oligonucleotide vaccination against Pseudomonas aeruginosa pneumonia. Microbiol Immunol 2019; 62:774-785. [PMID: 30378708 DOI: 10.1111/1348-0421.12658] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/13/2018] [Accepted: 10/27/2018] [Indexed: 01/15/2023]
Abstract
An effective vaccine against Pseudomonas aeruginosa would be hugely beneficial to people who are susceptible to the serious infections it can cause. Vaccination against PcrV of the P. aeruginosa type III secretion system is a potential prophylactic strategy for improving the incidence and prognosis of P. aeruginosa pneumonia. Here, the effect of nasal PcrV adjuvanted with CpG oligodeoxynucleotide (CpG) was compared with a nasal PcrV/aluminum hydroxide gel (alum) vaccine. Seven groups of mice were vaccinated intranasally with one of the following: 1, PcrV-CpG; 2, PcrV-alum; 3, PcrV alone; 4, CpG alone; 5, alum alone; 6 and 7, saline control. Fifty days after the first immunization, anti-PcrV IgG, IgA and IgG isotype titers were measured; significant increases in these titers were detected only in the PcrV-CpG vaccinated mice. The vaccinated mice were then intratracheally infected with a lethal dose of P. aeruginosa and their body temperatures and survival monitored for 24 hr, edema, bacteria, myeloperoxidase activity and lung histology also being evaluated at 24 hr post-infection. It was found that 73% of the PcrV-CpG-vaccinated mice survived, whereas fewer than 30% of the mice vaccinated with PcrV-alum or adjuvant alone survived. Lung edema and other inflammation-related variables were less severe in the PcrV-CpG group. The significant increase in PcrV-specific IgA titers detected following PcrV-CpG vaccination is probably a component of the disease protection mechanism. Overall, our data show that intranasal PcrV-CpG vaccination has potential efficacy for clinical application against P. aeruginosa pneumonia.
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Affiliation(s)
- Yoshifumi Naito
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kawaramachi Hirokoji, Kamigyo, Kyoto, 602-8566, Japan
| | - Saeko Hamaoka
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kawaramachi Hirokoji, Kamigyo, Kyoto, 602-8566, Japan
| | - Mao Kinoshita
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kawaramachi Hirokoji, Kamigyo, Kyoto, 602-8566, Japan
| | - Atsushi Kainuma
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kawaramachi Hirokoji, Kamigyo, Kyoto, 602-8566, Japan
| | - Masaru Shimizu
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kawaramachi Hirokoji, Kamigyo, Kyoto, 602-8566, Japan
| | - Hideya Katoh
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kawaramachi Hirokoji, Kamigyo, Kyoto, 602-8566, Japan
| | - Kiyoshi Moriyama
- Department of Anesthesiology, School of Medicine, Kyorin University, 6-20-2 Shinkawa, Mitaka, Tokyo, 181-8611, Japan
| | - Ken J Ishii
- Laboratory of Adjuvant Innovation, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Asagi, Saito, Ibaraki, Osaka, 567-0085, Japan.,Laboratory of Vaccine Science, Immunology Frontier Research Center, World Premier International Research Center, Osaka University, 1-1 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Teiji Sawa
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, 465 Kajiicho, Kawaramachi Hirokoji, Kamigyo, Kyoto, 602-8566, Japan
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26
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Pelfrene E, Mura M, Cavaleiro Sanches A, Cavaleri M. Monoclonal antibodies as anti-infective products: a promising future? Clin Microbiol Infect 2019; 25:60-64. [PMID: 29715552 PMCID: PMC7128139 DOI: 10.1016/j.cmi.2018.04.024] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 04/19/2018] [Accepted: 04/23/2018] [Indexed: 01/04/2023]
Abstract
BACKGROUND The paucity of licensed monoclonal antibodies (mAbs) in the infectious diseases arena strongly contrasts with the ready availability of these therapeutics for use in other conditions. AIMS This narrative review aims to assess the potential of monoclonal antibody-based interventions for infectious diseases. SOURCES A review of the literature via the Medline database was performed and complemented by published official documents on licensed anti-infective mAbs. In addition, ongoing trials were identified through a search of the clinical trial registration platform ClinicalTrials.gov. CONTENT We identified the few infections for which mAbs have been added to the therapeutic armamentarium and stressed their potential in representing a readily available protection tool against biothreats and newly emerging and reemerging infectious agents. In reviewing the historical context and main features of mAbs, we assert a potentially wider applicability and cite relevant examples of ongoing therapeutic developments. Factors hindering successful introduction of mAbs on a larger scale are outlined and thoughts are offered on how to possibly address some of these limitations. IMPLICATIONS mAbs may represent important tools in treating or preventing infections occurring with reasonably sufficient prevalence to justify demand and for which existing alternatives are not deemed fully adequate. Future initiatives need to address the prohibitive costs encountered in the development process. The feasibility of more large-scale administration of alternative modalities merits further exploration. In order to ensure optimal prospect of regulatory success, an early dialogue with competent authorities is encouraged.
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Affiliation(s)
- E Pelfrene
- Office of Anti-infectives and Vaccines, Human Medicines Evaluation Division, European Medicines Agency, London, UK.
| | - M Mura
- Office of Anti-infectives and Vaccines, Human Medicines Evaluation Division, European Medicines Agency, London, UK
| | - A Cavaleiro Sanches
- Quality Office, Human Medicines Research & Development Support Division, European Medicines Agency, London, UK
| | - M Cavaleri
- Office of Anti-infectives and Vaccines, Human Medicines Evaluation Division, European Medicines Agency, London, UK
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27
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Naran K, Nundalall T, Chetty S, Barth S. Principles of Immunotherapy: Implications for Treatment Strategies in Cancer and Infectious Diseases. Front Microbiol 2018; 9:3158. [PMID: 30622524 PMCID: PMC6308495 DOI: 10.3389/fmicb.2018.03158] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 12/05/2018] [Indexed: 12/13/2022] Open
Abstract
The advances in cancer biology and pathogenesis during the past two decades, have resulted in immunotherapeutic strategies that have revolutionized the treatment of malignancies, from relatively non-selective toxic agents to specific, mechanism-based therapies. Despite extensive global efforts, infectious diseases remain a leading cause of morbidity and mortality worldwide, necessitating novel, innovative therapeutics that address the current challenges of increasing antimicrobial resistance. Similar to cancer pathogenesis, infectious pathogens successfully fashion a hospitable environment within the host and modulate host metabolic functions to support their nutritional requirements, while suppressing host defenses by altering regulatory mechanisms. These parallels, and the advances made in targeted therapy in cancer, may inform the rational development of therapeutic interventions for infectious diseases. Although "immunotherapy" is habitually associated with the treatment of cancer, this review accentuates the evolving role of key targeted immune interventions that are approved, as well as those in development, for various cancers and infectious diseases. The general features of adoptive therapies, those that enhance T cell effector function, and ligand-based therapies, that neutralize or eliminate diseased cells, are discussed in the context of specific diseases that, to date, lack appropriate remedial treatment; cancer, HIV, TB, and drug-resistant bacterial and fungal infections. The remarkable diversity and versatility that distinguishes immunotherapy is emphasized, consequently establishing this approach within the armory of curative therapeutics, applicable across the disease spectrum.
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Affiliation(s)
- Krupa Naran
- Medical Biotechnology and Immunotherapy Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Trishana Nundalall
- Medical Biotechnology and Immunotherapy Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Shivan Chetty
- Medical Biotechnology and Immunotherapy Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Stefan Barth
- Medical Biotechnology and Immunotherapy Unit, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- South African Research Chair in Cancer Biotechnology, Department of Integrative Biomedical Sciences, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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28
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Amato DN, Amato DV, Adewunmi Y, Mavrodi OV, Parsons KH, Swilley SN, Braasch DA, Walker WD, Mavrodi DV, Patton DL. Using Aldehyde Synergism To Direct the Design of Degradable Pro-Antimicrobial Networks. ACS Appl Bio Mater 2018; 1:1983-1991. [DOI: 10.1021/acsabm.8b00500] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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29
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Affiliation(s)
- Charlotte Gaviard
- Normandie Univ, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France
- PISSARO Proteomic Facility, IRIB, 76821 Mont-Saint-Aignan, France
| | - Isabelle Broutin
- LCRB, UMR 8015, CNRS, University Paris Descartes, Sorbonne Paris City, 75270 Paris Cedex 06, France
| | - Pascal Cosette
- Normandie Univ, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France
- PISSARO Proteomic Facility, IRIB, 76821 Mont-Saint-Aignan, France
| | - Emmanuelle Dé
- Normandie Univ, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France
- PISSARO Proteomic Facility, IRIB, 76821 Mont-Saint-Aignan, France
| | - Thierry Jouenne
- Normandie Univ, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France
- PISSARO Proteomic Facility, IRIB, 76821 Mont-Saint-Aignan, France
| | - Julie Hardouin
- Normandie Univ, UNIROUEN, INSA Rouen, CNRS, PBS, 76000 Rouen, France
- PISSARO Proteomic Facility, IRIB, 76821 Mont-Saint-Aignan, France
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30
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van Geelen L, Meier D, Rehberg N, Kalscheuer R. (Some) current concepts in antibacterial drug discovery. Appl Microbiol Biotechnol 2018; 102:2949-2963. [PMID: 29455386 DOI: 10.1007/s00253-018-8843-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/05/2018] [Accepted: 02/06/2018] [Indexed: 12/30/2022]
Abstract
The rise of multidrug resistance in bacteria rendering pathogens unresponsive to many clinical drugs is widely acknowledged and considered a critical global healthcare issue. There is broad consensus that novel antibacterial chemotherapeutic options are extremely urgently needed. However, the development pipeline of new antibacterial drug lead structures is poorly filled and not commensurate with the scale of the problem since the pharmaceutical industry has shown reduced interest in antibiotic development in the past decades due to high economic risks and low profit expectations. Therefore, academic research institutions have a special responsibility in finding novel treatment options for the future. In this mini review, we want to provide a broad overview of the different approaches and concepts that are currently pursued in this research field.
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Affiliation(s)
- Lasse van Geelen
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University Düsseldorf, 40225, Dusseldorf, Germany
| | - Dieter Meier
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University Düsseldorf, 40225, Dusseldorf, Germany
| | - Nidja Rehberg
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University Düsseldorf, 40225, Dusseldorf, Germany
| | - Rainer Kalscheuer
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University Düsseldorf, 40225, Dusseldorf, Germany.
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31
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Wang-Lin SX, Balthasar JP. Pharmacokinetic and Pharmacodynamic Considerations for the Use of Monoclonal Antibodies in the Treatment of Bacterial Infections. Antibodies (Basel) 2018; 7:antib7010005. [PMID: 31544858 PMCID: PMC6698815 DOI: 10.3390/antib7010005] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/01/2018] [Accepted: 01/02/2018] [Indexed: 12/17/2022] Open
Abstract
Antibiotic-resistant bacterial pathogens are increasingly implicated in hospital- and community-acquired infections. Recent advances in monoclonal antibody (mAb) production and engineering have led to renewed interest in the development of antibody-based therapies for treatment of drug-resistant bacterial infections. Currently, there are three antibacterial mAb products approved by the Food and Drug Administration (FDA) and at least nine mAbs are in clinical trials. Antibacterial mAbs are typically developed to kill bacteria or to attenuate bacterial pathological activity through neutralization of bacterial toxins and virulence factors. Antibodies exhibit distinct pharmacological mechanisms from traditional antimicrobials and, hence, cross-resistance between small molecule antimicrobials and antibacterial mAbs is unlikely. Additionally, the long biological half-lives typically found for mAbs may allow convenient dosing and vaccine-like prophylaxis from infection. However, the high affinity of mAbs and the involvement of the host immune system in their pharmacological actions may lead to complex and nonlinear pharmacokinetics and pharmacodynamics. In this review, we summarize the pharmacokinetics and pharmacodynamics of the FDA-approved antibacterial mAbs and those are currently in clinical trials. Challenges in the development of antibacterial mAbs are also discussed.
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Affiliation(s)
- Shun Xin Wang-Lin
- Department of Pharmaceutical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14214, USA.
| | - Joseph P Balthasar
- Department of Pharmaceutical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14214, USA.
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32
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Miller LA. The best defense is a good (Protease) offense: How Pseudomonas aeruginosa evades mucosal immunity in the lung. Virulence 2017; 8:625-627. [PMID: 28102763 DOI: 10.1080/21505594.2016.1278335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Lisa A Miller
- a Department of Anatomy , Physiology, and Cell Biology, UC Davis School of Veterinary Medicine & California National Primate Research Center , Davis , CA , USA
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33
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Gholizadeh P, Maftoon H, Aghazadeh M, Asgharzadeh M, Kafil HS. Current opinions in the infection control of carbapenem-resistant Enterobacteriaceae species and Pseudomonas aeruginosa. ACTA ACUST UNITED AC 2017; 28:97-103. [DOI: 10.1097/mrm.0000000000000107] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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34
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Hamaoka S, Naito Y, Katoh H, Shimizu M, Kinoshita M, Akiyama K, Kainuma A, Moriyama K, Ishii KJ, Sawa T. Efficacy comparison of adjuvants in PcrV vaccine against Pseudomonas aeruginosa pneumonia. Microbiol Immunol 2017; 61:64-74. [PMID: 28370521 DOI: 10.1111/1348-0421.12467] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 01/16/2017] [Accepted: 01/19/2017] [Indexed: 11/27/2022]
Abstract
Vaccination against the type III secretion system of P. aeruginosa is a potential prophylactic strategy for reducing the incidence and improving the poor prognosis of P. aeruginosa pneumonia. In this study, the efficacies of three different adjuvants, Freund's adjuvant (FA), aluminum hydroxide (alum) and CpG oligodeoxynucleotide (ODN), were examined from the viewpoint of inducing PcrV-specific immunity against virulent P. aeruginosa. Mice that had been immunized intraperitoneally with recombinant PcrV formulated with one of the above adjuvants were challenged intratracheally with a lethal dose of P. aeruginosa. The PcrV-FA immunized group attained a survival rate of 91%, whereas the survival rates of the PcrV-alum and PcrV-CpG groups were 73% and 64%, respectively. In terms of hypothermia recovery after bacterial instillation, PcrV-alum was the most protective, followed by PcrV-FA and PcrV-CpG. The lung edema index was lower in the PcrV-CpG vaccination group than in the other groups. PcrV-alum immunization was associated with the greatest decrease in myeloperoxidase in infected lungs, and also decreased the number of lung bacteria to a similar number as in the PcrV-FA group. There was less neutrophil recruitment in the lungs of mice vaccinated with PcrV-alum or PcrV-CpG than in those of mice vaccinated with PcrV-FA or PcrV alone. Overall, in terms of mouse survival the PcrV-CpG vaccine, which could be a relatively safe next-generation vaccine, showed a comparable effect to the PcrV-alum vaccine.
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Affiliation(s)
- Saeko Hamaoka
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Yoshifumi Naito
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Hideya Katoh
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Masaru Shimizu
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Mao Kinoshita
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Koichi Akiyama
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Atsushi Kainuma
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Kiyoshi Moriyama
- Department of Anesthesiology, School of Medicine, Kyorin University, Mitaka 181-8611, Japan
| | - Ken J Ishii
- Laboratory of Adjuvant Innovation, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Osaka 567-0085, Japan.,Laboratory of Vaccine Science, Immunology Frontier Research Center, World Premier International Research Center, Osaka University, Suita, Osaka 565-0871, Japan
| | - Teiji Sawa
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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35
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Abstract
The rapid evolution and dissemination of antibiotic resistance among bacterial pathogens are outpacing the development of new antibiotics, but antivirulence agents provide an alternative. These agents can circumvent antibiotic resistance by disarming pathogens of virulence factors that facilitate human disease while leaving bacterial growth pathways - the target of traditional antibiotics - intact. Either as stand-alone medications or together with antibiotics, these drugs are intended to treat bacterial infections in a largely pathogen-specific manner. Notably, development of antivirulence drugs requires an in-depth understanding of the roles that diverse virulence factors have in disease processes. In this Review, we outline the theory behind antivirulence strategies and provide examples of bacterial features that can be targeted by antivirulence approaches. Furthermore, we discuss the recent successes and failures of this paradigm, and new developments that are in the pipeline.
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Affiliation(s)
- Seth W Dickey
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, The National Institutes of Health, Bethesda, Maryland 20814, USA
| | - Gordon Y C Cheung
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, The National Institutes of Health, Bethesda, Maryland 20814, USA
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, The National Institutes of Health, Bethesda, Maryland 20814, USA
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Yasumoto H, Katoh H, Kinoshita M, Shimizu M, Hamaoka S, Akiyama K, Naito Y, Sawa T. Epidemiological analysis of serum anti-Pseudomonas aeruginosa PcrV titers in adults. Microbiol Immunol 2016; 60:114-20. [PMID: 26696420 DOI: 10.1111/1348-0421.12353] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 12/14/2015] [Accepted: 12/15/2015] [Indexed: 01/11/2023]
Abstract
Of the various virulence mechanisms of the opportunistic pathogen Pseudomonas aeruginosa, the type III secretion system (TTSS) has been characterized as a major factor associated with acute lung injury, bacteremia and mortality. In addition, PcrV, a component protein of the TTSS, has been characterized as a protective antigen against infection with P. aeruginosa. This study comprised an epidemiological analysis of serum anti-PcrV titers in a cohort of Japanese adults. From April 2012 to March 2013, serum anti-PcrV titers of 198 volunteer participants undergoing anesthesia for scheduled surgeries were measured. The median, minimum and maximum serum anti-PcrV titers among the 198 participants were 4.09 nM, 1.01 nM and 113.81 nM, respectively. The maximum peaks in the histogram were within the anti-PcrV 2.00-4.99 nM titer range; values for 115 participants (58.1%) were within this range. Anti-PcrV titers were more than approximately three-fold greater (>12 nM) than the median value in 21 participants (10.6%). Ten-year interval age increases, history of treatment for traffic trauma, and a history of past surgery each showed statistically significant associations with higher anti-PcrV titers (i.e., >10 nM) than did the other factors assessed by binomial analysis. This study revealed a considerable variation in anti-PcrV titers in adult subjects without any obvious histories of infection with P. aeruginosa.
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Affiliation(s)
- Hiroaki Yasumoto
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Hideya Katoh
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Mao Kinoshita
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Masaru Shimizu
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Saeko Hamaoka
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Koichi Akiyama
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Yoshifumi Naito
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Teiji Sawa
- Department of Anesthesiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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Apgar JR, Mader M, Agostinelli R, Benard S, Bialek P, Johnson M, Gao Y, Krebs M, Owens J, Parris K, St. Andre M, Svenson K, Morris C, Tchistiakova L. Beyond CDR-grafting: Structure-guided humanization of framework and CDR regions of an anti-myostatin antibody. MAbs 2016; 8:1302-1318. [PMID: 27625211 PMCID: PMC5058614 DOI: 10.1080/19420862.2016.1215786] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 06/23/2016] [Accepted: 07/18/2016] [Indexed: 01/29/2023] Open
Abstract
Antibodies are an important class of biotherapeutics that offer specificity to their antigen, long half-life, effector function interaction and good manufacturability. The immunogenicity of non-human-derived antibodies, which can be a major limitation to development, has been partially overcome by humanization through complementarity-determining region (CDR) grafting onto human acceptor frameworks. The retention of foreign content in the CDR regions, however, is still a potential immunogenic liability. Here, we describe the humanization of an anti-myostatin antibody utilizing a 2-step process of traditional CDR-grafting onto a human acceptor framework, followed by a structure-guided approach to further reduce the murine content of CDR-grafted antibodies. To accomplish this, we solved the co-crystal structures of myostatin with the chimeric (Protein Databank (PDB) id 5F3B) and CDR-grafted anti-myostatin antibody (PDB id 5F3H), allowing us to computationally predict the structurally important CDR residues as well as those making significant contacts with the antigen. Structure-based rational design enabled further germlining of the CDR-grafted antibody, reducing the murine content of the antibody without affecting antigen binding. The overall "humanness" was increased for both the light and heavy chain variable regions.
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Affiliation(s)
| | | | | | - Susan Benard
- Biomedicine Design, Pfizer Inc., Cambridge, MA, USA
| | - Peter Bialek
- Rare Disease Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Mark Johnson
- Rare Disease Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Yijie Gao
- Biomedicine Design, Pfizer Inc., Cambridge, MA, USA
| | - Mark Krebs
- Biomedicine Design, Pfizer Inc., Cambridge, MA, USA
| | - Jane Owens
- Rare Disease Research Unit, Pfizer Inc., Cambridge, MA, USA
| | - Kevin Parris
- Biomedicine Design, Pfizer Inc., Cambridge, MA, USA
| | | | - Kris Svenson
- Biomedicine Design, Pfizer Inc., Cambridge, MA, USA
| | - Carl Morris
- Rare Disease Research Unit, Pfizer Inc., Cambridge, MA, USA
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Kinoshita M, Kato H, Yasumoto H, Shimizu M, Hamaoka S, Naito Y, Akiyama K, Moriyama K, Sawa T. The prophylactic effects of human IgG derived from sera containing high anti-PcrV titers against pneumonia-causing Pseudomonas aeruginosa. Hum Vaccin Immunother 2016; 12:2833-2846. [PMID: 27454613 DOI: 10.1080/21645515.2016.1209280] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The PcrV cap structure of the type III secretory apparatus of Pseudomonas aeruginosa is a vaccine target. Human immunoglobulin G (IgG) molecules extracted from sera containing high or low anti-PcrV titers were tested for their effects against P. aeruginosa pneumonia in a mouse model. Among 198 volunteers, we selected the top 10 high anti-PcrV titer sera and the bottom 10 low anti-PcrV titer sera and extracted the IgG fraction from each serum sample. First, we examined the effects of the IgG against virulent P. aeruginosa. A lethal dose of P. aeruginosa premixed with saline, low titer human IgG, high titer human IgG, or rabbit-derived polyclonal anti-PcrV IgG was intratracheally administered into the lungs of mice, and their survival and lung inflammation were evaluated for 24 h. The high anti-PcrV titer human IgG had a prophylactic effect. Next, the prophylactic effects of intravenous administration of extracted and pooled high or low anti-PcrV titer human IgG were examined. Here, prophylactic intravenous administration of pooled high anti-PcrV titer human IgG, which showed binding capacity to P. aeruginosa PcrV, was more effective than the administration of its low titer pooled equivalent, and the measured physiological and inflammatory parameters correlated with the anti-PcrV titer levels. This result indirectly implies that high anti-PcrV titers in blood can help to protect against virulent P. aeruginosa infections. In addition, the IgG fractions from such high titer sera have potential to be a source of specific intravenous immunoglobulin products for passive vaccination against virulent P. aeruginosa infections.
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Affiliation(s)
- Mao Kinoshita
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
| | - Hideya Kato
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
| | - Hiroaki Yasumoto
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
| | - Masaru Shimizu
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
| | - Saeko Hamaoka
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
| | - Yoshifumi Naito
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
| | - Koichi Akiyama
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
| | - Kiyoshi Moriyama
- b Department of Anesthesiology , School of Medicine, Kyorin University , Mitaka , Japan
| | - Teiji Sawa
- a Department of Anesthesiology , Kyoto Prefectural University of Medicine , Kyoto , Japan
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Anantharajah A, Mingeot-Leclercq MP, Van Bambeke F. Targeting the Type Three Secretion System in Pseudomonas aeruginosa. Trends Pharmacol Sci 2016; 37:734-749. [PMID: 27344210 DOI: 10.1016/j.tips.2016.05.011] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 05/15/2016] [Accepted: 05/17/2016] [Indexed: 12/11/2022]
Abstract
The injectisome type three secretion system (T3SS) is a major virulence factor in Pseudomonas aeruginosa. This bacterium is responsible for severe infections in immunosuppressed or cystic fibrosis patients and has become resistant to many antibiotics. Inhibitors of T3SS may therefore constitute an innovative therapeutic target. After a brief description of the T3SS and its regulation, this review presents strategies to inhibit T3SS-mediated toxicity and describes the main families of existing inhibitors. Over the past few years, 12 classes of small-molecule inhibitors and two types of antibody have been discovered and evaluated in vitro for their capacity to inhibit T3SS expression or function, and to protect host cells from T3SS-mediated cytotoxicity. While only one small molecule has been tested in vivo, a bifunctional antibody targeting both the translocation apparatus of the T3SS and a surface polysaccharide is currently in Phase II clinical trials.
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Affiliation(s)
- Ahalieyah Anantharajah
- Pharmacologie Cellulaire et Moléculaire, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Marie-Paule Mingeot-Leclercq
- Pharmacologie Cellulaire et Moléculaire, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Françoise Van Bambeke
- Pharmacologie Cellulaire et Moléculaire, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium.
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De Tavernier E, Detalle L, Morizzo E, Roobrouck A, De Taeye S, Rieger M, Verhaeghe T, Correia A, Van Hegelsom R, Figueirido R, Noens J, Steffensen S, Stöhr T, Van de Velde W, Depla E, Dombrecht B. High Throughput Combinatorial Formatting of PcrV Nanobodies for Efficient Potency Improvement. J Biol Chem 2016; 291:15243-55. [PMID: 27226529 DOI: 10.1074/jbc.m115.684241] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Indexed: 11/06/2022] Open
Abstract
Improving potencies through concomitant blockage of multiple epitopes and avid binding by fusing multiple (different) monovalent Nanobody building blocks via linker sequences into one multivalent polypeptide chain is an elegant alternative to affinity maturation. We explored a large and random formatting library of bivalent (combinations of two identical) and biparatopic (combinations of two different) Nanobodies for functional blockade of Pseudomonas aeruginosa PcrV. PcrV is an essential part of the P. aeruginosa type III secretion system (T3SS), and its oligomeric nature allows for multiple complex binding and blocking options. The library screening yielded a large number of promising biparatopic lead candidates, revealing significant (and non-trivial) preferences in terms of Nanobody building block and epitope bin combinations and orientations. Excellent potencies were confirmed upon further characterization in two different P. aeruginosa T3SS-mediated cytotoxicity assays. Three biparatopic Nanobodies were evaluated in a lethal mouse P. aeruginosa challenge pneumonia model, conferring 100% survival upon prophylactic administration and reducing lung P. aeruginosa burden by up to 2 logs. At very low doses, they protected the mice from P. aeruginosa infection-related changes in lung histology, myeloperoxidase production, and lung weight. Importantly, the most potent Nanobody still conferred protection after therapeutic administration up to 24 h post-infection. The concept of screening such formatting libraries for potency improvement is applicable to other targets and biological therapeutic platforms.
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Affiliation(s)
| | | | - Erika Morizzo
- From Ablynx N.V., Technologiepark 21, 9052 Ghent, Belgium
| | | | | | - Melanie Rieger
- From Ablynx N.V., Technologiepark 21, 9052 Ghent, Belgium
| | - Tom Verhaeghe
- From Ablynx N.V., Technologiepark 21, 9052 Ghent, Belgium
| | | | | | | | - Jeroen Noens
- From Ablynx N.V., Technologiepark 21, 9052 Ghent, Belgium
| | | | - Thomas Stöhr
- From Ablynx N.V., Technologiepark 21, 9052 Ghent, Belgium
| | | | - Erik Depla
- From Ablynx N.V., Technologiepark 21, 9052 Ghent, Belgium
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Katoh H, Yasumoto H, Shimizu M, Hamaoka S, Kinoshita M, Akiyama K, Sawa T. IV Immunoglobulin for Acute Lung Injury and Bacteremia in Pseudomonas aeruginosa Pneumonia. Crit Care Med 2016; 44:e12-24. [PMID: 26317571 DOI: 10.1097/CCM.0000000000001271] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVES Virulent and multidrug-resistant Pseudomonas aeruginosa causes a lethal pneumonia, especially in patients who are artificially ventilated. It has been reported that the virulence mechanism used by P. aeruginosa, which is linked to acute lung injury, is strongly associated with the type III secretion system, and specific antibodies targeting this system have shown a protective effect in both experimental and clinical settings. We investigated the effect of administering IV immunoglobulins on P. aeruginosa pneumonia, including its associated bacteremia and mortality, although focusing especially on type III secretion system-associated P. aeruginosa virulence. DESIGN Prospective randomized and controlled animal study. SETTING University laboratory. SUBJECTS Male ICR mice. INTERVENTIONS Mice were infected intratracheally with a lethal dose of the virulent P. aeruginosa PA103 strain. IV immunoglobulin administration was examined in three different settings: 1) premixed; 2) pre-IV, prophylactic administration before bacterial infection; and 3) post-IV, therapeutic administration after bacterial infection. The effect of specific antigen titer depletion of IV immunoglobulins was also examined. MEASUREMENTS AND MAIN RESULTS Survival and body temperature were monitored for 24 hours. Bacteremia, cytokine concentration, myeloperoxidase activity, WBC counts in the blood, and lung bacterial load were evaluated. Survival improved significantly in mice that received IV immunoglobulins (p < 0.05). Lung edema, lung bacteriologic load, and bacteremia decreased significantly in the IV immunoglobulin-treated mice (p < 0.05). The mechanism of protection was associated with the presence of antibodies against both PcrV and some bacterial surface antigens in the IV immunoglobulins. CONCLUSIONS IV immunoglobulin administration had a significantly protective effect against lethal infection from virulent P. aeruginosa. Prophylactic IV immunoglobulin administration at the highest dose was comparable with that achieved by administrating a specific anti-PcrV polyclonal IgG into the mice. The mechanism of protection is likely to involve the synergic action of anti-PcrV titers and antibodies against some surface antigen(s) that block the type III secretion system-associated virulence of P. aeruginosa.
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Shimizu M, Katoh H, Hamaoka S, Kinoshita M, Akiyama K, Naito Y, Sawa T. Protective effects of intravenous immunoglobulin and antimicrobial agents on acute pneumonia in leukopenic mice. J Infect Chemother 2016; 22:240-7. [DOI: 10.1016/j.jiac.2016.01.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 12/10/2015] [Accepted: 01/06/2016] [Indexed: 01/08/2023]
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Falcó V, Burgos J, Papiol E, Ferrer R, Almirante B. Investigational drugs in phase I and phase II clincial trials for the treatment of hospital-acquired pneumonia. Expert Opin Investig Drugs 2016; 25:653-65. [PMID: 26998623 DOI: 10.1517/13543784.2016.1168803] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Hospital acquired pneumonia (HAP) is one of the main infections acquired by patients during a stay in hospital. The main issue when dealing with patients with HAP and ventilator associated pneumonia (VAP) is the increasing role of multi-drug resistant organisms (MDROs). AREAS COVERED In this review the authors summarize the actual situation of MDROs as a cause of HAP and VAP. They also review the current treatment options stated in the most important international guidelines. Finally, they focus on the investigational drugs that have reached the phase III stage of development and the novel compounds that are being studied in phase I and II clinical trials. EXPERT OPINION Thanks to their excellent activity against MDROs, drugs in development for the treatment of HAP and VAP can significantly improve the therapeutic options available. In selected patients, the possibility to administer directed therapy with monoclonal antibodies to specific pathogens is an exciting strategy in the fight against widespread resistance.
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Affiliation(s)
- Vicenç Falcó
- a Infectious Diseases Department, University Hospital Vall d'Hebron , Universitat Autònoma de Barcelona , Barcelona , Spain
| | - Joaquin Burgos
- a Infectious Diseases Department, University Hospital Vall d'Hebron , Universitat Autònoma de Barcelona , Barcelona , Spain
| | - Elisabeth Papiol
- b Intensive Care Department, University Hospital Vall d'Hebron , Universitat Autònoma de Barcelona , Barcelona , Spain
| | - Ricard Ferrer
- b Intensive Care Department, University Hospital Vall d'Hebron , Universitat Autònoma de Barcelona , Barcelona , Spain
| | - Benito Almirante
- a Infectious Diseases Department, University Hospital Vall d'Hebron , Universitat Autònoma de Barcelona , Barcelona , Spain
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Abstract
Antibodies and passive antibody therapy in the treatment of infectious diseases is the story of a treatment concept which dates back more than 120 years, to the 1890s, when the use of serum from immunized animals provided the first effective treatment options against infections with Clostridium tetani and Corynebacterium diphtheriae. However, after the discovery of penicillin by Fleming in 1928, and the subsequent introduction of the much cheaper and safer antibiotics in the 1930s, serum therapy was largely abandoned. However, the broad and general use of antibiotics in human and veterinary medicine has resulted in the development of multi-resistant strains of bacteria with limited to no response to existing treatments and the need for alternative treatment options. The combined specificity and flexibility of antibody-based treatments makes them very valuable tools for designing specific antibody treatments to infectious agents. These attributes have already caused a revolution in new antibody-based treatments in oncology and inflammatory diseases, with many approved products. However, only one monoclonal antibody, palivizumab, for the prevention and treatment of respiratory syncytial virus, is approved for infectious diseases. The high cost of monoclonal antibody therapies, the need for parallel development of diagnostics, and the relatively small markets are major barriers for their development in the presence of cheap antibiotics. It is time to take a new and revised look into the future to find appropriate niches in infectious diseases where new antibody-based treatments or combinations with existing antibiotics, could prove their value and serve as stepping stones for broader acceptance of the potential for and value of these treatments.
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Abstract
Pseudomonas aeruginosa is an opportunistic bacterial pathogen that causes fatal acute lung infections in critically ill individuals. Its pathogenesis is associated with bacterial virulence conferred by the type III secretion system (TTSS), through which P. aeruginosa causes necrosis of the lung epithelium and disseminates into the circulation, resulting in bacteremia, sepsis, and mortality. TTSS allows P. aeruginosa to directly translocate cytotoxins into eukaryotic cells, inducing cell death. The P. aeruginosa V-antigen PcrV, a homolog of the Yersinia V-antigen LcrV, is an indispensable contributor to TTS toxin translocation. Vaccination against PcrV ensures the survival of challenged mice and decreases lung inflammation and injury. Both the rabbit polyclonal anti-PcrV antibody and the murine monoclonal anti-PcrV antibody, mAb166, inhibit TTS toxin translocation. mAb166 IgG was cloned, and a molecular engineered humanized anti-PcrV IgG antigen-binding fragment, KB001, was developed for clinical use. KB001 is currently undergoing Phase-II clinical trials for ventilator-associated pneumonia in France and chronic pneumonia in cystic fibrosis in USA. In these studies, KB001 has demonstrated its safety, a favorable pharmacokinetic profile, and promising potential as a nonantibiotic strategy to reduce airway inflammation and damage in P. aeruginosa pneumonia.
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Key Words
- CF, cystic fibrosis
- Fab, fragment antigen binding
- Fc, fragment crystallizable region
- MDR, multidrug resistant
- MDRP, multidrug resistant Pseudomonas aeruginosa
- P. aeruginosa, Pseudomonas aeruginosa
- PcrV
- Pseudomonas aeruginosa
- TTS, type III secretory
- TTSS, type III secretion system
- V-antigen
- VAP, ventilator-associated pneumonia
- antibody
- immunoglobulin G, IgG
- mAb, monoclonal antibody
- type III secretion system
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Affiliation(s)
- Teiji Sawa
- a Department of Anesthesiology ; Kyoto Prefectural University of Medicine ; Kyoto , Japan
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Thaden JT, Keller AE, Shire NJ, Camara MM, Otterson L, Huband M, Guenther CM, Zhao W, Warrener P, Stover CK, Fowler VG, DiGiandomenico A. Pseudomonas aeruginosa Bacteremic Patients Exhibit Nonprotective Antibody Titers Against Therapeutic Antibody Targets PcrV and Psl Exopolysaccharide. J Infect Dis 2015; 213:640-8. [PMID: 26333940 DOI: 10.1093/infdis/jiv436] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 08/26/2015] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND The type 3 secretion protein PcrV and Psl exopolysaccharide are promising therapeutic antibody targets against Pseudomonas aeruginosa. We examined P. aeruginosa bloodstream infection (BSI) isolates for the ability to express PcrV and Psl and evaluated corresponding patient serum for active titers to these targets. METHODS We identified 114 patients with acute P. aeruginosa BSI; 56 cases were accompanied by acute sera. Serum was evaluated for PcrV- and Psl-specific immunoglobulin G (IgG) and for cytotoxicity and opsonophagocytosis. Isolates were evaluated for susceptibility to antibiotics, expression of PcrV and Psl, and susceptibility to the anti-PcrV/Psl bispecific antibody and clinical candidate MEDI3902. RESULTS In-hospital mortality for patients with P. aeruginosa BSI was 39%. A total of 26% of isolates were resistant to ≥3 antibiotic classes. Although PcrV and/or Psl were detected in 99% of isolates, a majority of patients lacked active titers to PcrV (100%) and Psl (98%). In addition, MEDI3902 was active against all tested isolates. CONCLUSIONS A vast majority of P. aeruginosa BSI isolates express PcrV and Psl; however, patient sera most often lacked IgG and functionally active responses to these targets. These results suggest that therapies directed at PcrV and Psl could be a promising approach for combating P. aeruginosa bloodstream infections.
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Affiliation(s)
- Joshua T Thaden
- Division of Infectious Diseases, Duke University, Durham, North Carolina
| | | | | | | | | | | | | | - Wei Zhao
- MedImmune, LLC, Gaithersburg, Maryland
| | | | | | - Vance G Fowler
- Division of Infectious Diseases, Duke University, Durham, North Carolina
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DiGiandomenico A, Sellman BR. Antibacterial monoclonal antibodies: the next generation? Curr Opin Microbiol 2015; 27:78-85. [PMID: 26302478 DOI: 10.1016/j.mib.2015.07.014] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 07/28/2015] [Accepted: 07/30/2015] [Indexed: 12/21/2022]
Abstract
There is a clear need for renewed efforts to combat the increasing incidence of antibiotic resistance. While the antibiotic resistance epidemic is due in part to the misuse of antibiotics, even proper empiric antibiotic therapy increases the selective pressure and potential for drug-resistance and spread of resistance mechanisms between bacteria. Antibiotic resistance coupled with the detrimental effects of broad-spectrum antibiotics on the healthy microbiome, have led the field to explore pathogen specific antibacterials such as monoclonal antibodies (mAbs). Medical need along with advances in mAb discovery, engineering, and production have driven significant effort developing mAb-based antibacterials. If successful, they will provide physicians with precision weapons to combat bacterial infections and can help prevent a return to a pre-antibiotic era.
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Abstract
Whereas active immunity refers to the process of exposing the individual to an antigen to generate an adaptive immune response, passive immunity refers to the transfer of antibodies from one individual to another. Passive immunity provides immediate but short-lived protection, lasting several weeks up to 3 or 4 months. Passive immunity can occur naturally, when maternal antibodies are transferred to the fetus through the placenta or from breast milk to the gut of the infant. It can also be produced artificially, when antibody preparations derived from sera or secretions of immunized donors or, more recently, different antibody producing platforms are transferred via systemic or mucosal route to nonimmune individuals. Passive immunization has recently become an attractive approach because of the emergence of new and drug-resistant microorganisms, diseases that are unresponsive to drug therapy and individuals with an impaired immune system who are unable to respond to conventional vaccines. This chapter addresses the contributions of natural and artificial acquired passive immunity in understanding the concept of passive immunization. We will mainly focus on administration of antibodies for protection against various infectious agents entering through mucosal surfaces.
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50
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Sawa T, Shimizu M, Moriyama K, Wiener-Kronish JP. Association between Pseudomonas aeruginosa type III secretion, antibiotic resistance, and clinical outcome: a review. Crit Care 2014; 18:668. [PMID: 25672496 PMCID: PMC4331484 DOI: 10.1186/s13054-014-0668-9] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Pseudomonas aeruginosa uses a complex type III secretion system to inject the toxins ExoS, ExoT, ExoU, and ExoY into the cytosol of target eukaryotic cells. This system is regulated by the exoenzyme S regulon and includes the transcriptional activator ExsA. Of the four toxins, ExoU is characterized as the major virulence factor responsible for alveolar epithelial injury in patients with P. aeruginosa pneumonia. Virulent strains of P. aeruginosa possess the exoU gene, whereas non-virulent strains lack this particular gene. The mechanism of virulence for the exoU+ genotype relies on the presence of a pathogenic gene cluster (PAPI-2) encoding exoU and its chaperone, spcU. The ExoU toxin has a patatin-like phospholipase domain in its N-terminal, exhibits phospholipase A2 activity, and requires a eukaryotic cell factor for activation. The C-terminal of ExoU has a ubiquitinylation mechanism of activation. This probably induces a structural change in enzymatic active sites required for phospholipase A2 activity. In P. aeruginosa clinical isolates, the exoU+ genotype correlates with a fluoroquinolone resistance phenotype. Additionally, poor clinical outcomes have been observed in patients with pneumonia caused by exoU+-fluoroquinolone-resistant isolates. Therefore, the potential exists to improve clinical outcomes in patients with P. aeruginosa pneumonia by identifying virulent and antimicrobial drug-resistant strains through exoU genotyping or ExoU protein phenotyping or both.
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