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Sharma-Kuinkel BK, Tkaczyk C, Bonnell J, Yu L, Tovchigrechko A, Tabor DE, Park LP, Ruffin F, Esser MT, Sellman BR, Fowler VG, Ruzin A. Associations of pathogen-specific and host-specific characteristics with disease outcome in patients with Staphylococcus aureus bacteremic pneumonia. Clin Transl Immunology 2019; 8:e01070. [PMID: 31360464 PMCID: PMC6640002 DOI: 10.1002/cti2.1070] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 06/24/2019] [Accepted: 06/30/2019] [Indexed: 11/08/2022] Open
Abstract
Objective To understand the relationships of Staphylococcus aureus (SA) bacteremic pneumonia (SABP) outcome with patient‐specific and SA‐specific variables. Methods We analysed SA bloodstream isolates and matching sera in SABP patients by sequencing SA isolates (n = 50) and measuring in vitro AT production, haemolytic activity and expression of ClfA and ClfB. Controls were sera from gram‐negative bacteremia patients with or without pneumonia and uninfected subjects. Levels of IgGs, IgMs and neutralizing antibodies (NAbs) against SA antigens were quantified and analysed by one‐way ANOVA. Associations of patient outcomes with patient variables, antibody levels and isolate characteristics were evaluated by univariate and multivariate logistic regression analyses. Results SABP patients had higher levels of IgGs against eight virulence factors and anti‐alpha toxin (AT) NAbs than uninfected controls. Levels of IgG against AT and IgMs against ClfA, FnbpA and SdrC were higher in clinically cured SABP patients than in clinical failures. Anti‐LukAB NAb levels were elevated in all cohorts. Increased odds of cure correlated with higher haemolytic activity of SA strains, longer time between surgery and bacteremia (> 30 days), longer duration of antibiotic therapy, lower acute physiology and total APACHE II scores, lack of persistent fever for > 72 h and higher levels of antibodies against AT (IgG), ClfA (IgM), FnbpA (IgM) and SdrC (IgM). Discussion Limitations included the cross‐sectional observational nature of the study, small sample size and inability to measure antibody levels against all SA virulence factors. Conclusion Our results suggest that SABP patients may benefit from immunotherapy targeting multiple SA antigens.
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Affiliation(s)
- Batu K Sharma-Kuinkel
- Division of Infectious Diseases, Department of Medicine, Duke University Durham NC USA
| | | | | | - Li Yu
- Statistical Sciences, AstraZeneca Gaithersburg MD USA
| | | | | | - Lawrence P Park
- Division of Infectious Diseases, Department of Medicine, Duke University Durham NC USA
| | - Felicia Ruffin
- Division of Infectious Diseases, Department of Medicine, Duke University Durham NC USA
| | - Mark T Esser
- Microbial Sciences, AstraZeneca Gaithersburg MD USA
| | | | - Vance G Fowler
- Division of Infectious Diseases, Department of Medicine, Duke University Durham NC USA
| | - Alexey Ruzin
- Microbial Sciences, AstraZeneca Gaithersburg MD USA
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Jones-Nelson O, Hilliard JJ, DiGiandomenico A, Warrener P, Alfaro A, Cheng L, Stover CK, Cohen TS, Sellman BR. The Neutrophilic Response to Pseudomonas Damages the Airway Barrier, Promoting Infection by Klebsiella pneumoniae. Am J Respir Cell Mol Biol 2019; 59:745-756. [PMID: 30109945 DOI: 10.1165/rcmb.2018-0107oc] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pseudomonas aeruginosa and Klebsiella pneumoniae are two common gram-negative pathogens that are associated with bacterial pneumonia and can often be isolated from the same patient. We used a mixed-pathogen pneumonia infection model in which mice were infected with sublethal concentrations of P. aeruginosa and K. pneumoniae, resulting in significant lethality, outgrowth of both bacteria in the lung, and systemic dissemination of K. pneumoniae. Inflammation, induced by P. aeruginosa activation of Toll-like receptor 5, results in prolonged neutrophil recruitment to the lung and increased levels of neutrophil elastase in the airway, resulting in lung damage and epithelial barrier dysfunction. Live P. aeruginosa was not required to potentiate K. pneumoniae infection, and flagellin alone was sufficient to induce lethality when delivered along with Klebsiella. Prophylaxis with an anti-Toll-like receptor 5 antibody or Sivelestat, a neutrophil elastase inhibitor, reduced neutrophil influx, inflammation, and mortality. Furthermore, pathogen-specific monoclonal antibodies targeting P. aeruginosa or K. pneumoniae prevented the outgrowth of both bacteria and reduced host inflammation and lethality. These findings suggest that coinfection with P. aeruginosa may enable the outgrowth and dissemination of K. pneumoniae, and that a pathogen- or host-specific prophylactic approach targeting P. aeruginosa may prevent or limit the severity of such infections by reducing neutrophil-induced lung damage.
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Affiliation(s)
| | | | | | | | - Alex Alfaro
- 2 Department of Laboratory Animal Research, and
| | - Lily Cheng
- 3 Department of Translational Science, MedImmune, LLC, Gaithersburg, Maryland
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Staphylococcus aureus Toxins: From Their Pathogenic Roles to Anti-virulence Therapy Using Natural Products. BIOTECHNOL BIOPROC E 2019. [DOI: 10.1007/s12257-019-0059-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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S. aureus Evades Macrophage Killing through NLRP3-Dependent Effects on Mitochondrial Trafficking. Cell Rep 2019; 22:2431-2441. [PMID: 29490278 PMCID: PMC7160668 DOI: 10.1016/j.celrep.2018.02.027] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 01/05/2018] [Accepted: 02/06/2018] [Indexed: 12/28/2022] Open
Abstract
Clinical severity of Staphylococcus aureus respiratory infection correlates with alpha toxin (AT) expression. AT activates the NLRP3 inflammasome; deletion of Nlrp3, or AT neutralization, protects mice from lethal S. aureus pneumonia. We tested the hypothesis that this protection is not due to a reduction in inflammasome-dependent cytokines (IL-1β/IL-18) but increased bactericidal function of macrophages. In vivo, neutralization of AT or NLRP3 improved bacterial clearance and survival, while blocking IL-1β/IL-18 did not. Primary human monocytes were used in vitro to determine the mechanism through which NLRP3 alters bacterial killing. In cells treated with small interfering RNA (siRNA) targeting NLRP3 or infected with AT-null S. aureus, mitochondria co-localize with bacterial-containing phagosomes. Mitochondrial engagement activates caspase-1, a process dependent on complex II of the electron transport chain, near the phagosome, promoting its acidification. These data demonstrate a mechanism utilized by S. aureus to sequester itself from antimicrobial processes within the cell.
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Abstract
Staphylococcus aureus has become a serious threat to human health. In addition to having increased antibiotic resistance, the bacterium is a master at adapting to its host by evading almost every facet of the immune system, the so-called immune evasion proteins. Many of these immune evasion proteins target neutrophils, the most important immune cells in clearing S. aureus infections. The neutrophil attacks pathogens via a plethora of strategies. Therefore, it is no surprise that S. aureus has evolved numerous immune evasion strategies at almost every level imaginable. In this review we discuss step by step the aspects of neutrophil-mediated killing of S. aureus, such as neutrophil activation, migration to the site of infection, bacterial opsonization, phagocytosis, and subsequent neutrophil-mediated killing. After each section we discuss how S. aureus evasion molecules are able to resist the neutrophil attack of these different steps. To date, around 40 immune evasion molecules of S. aureus are known, but its repertoire is still expanding due to the discovery of new evasion proteins and the addition of new functions to already identified evasion proteins. Interestingly, because the different parts of neutrophil attack are redundant, the evasion molecules display redundant functions as well. Knowing how and with which proteins S. aureus is evading the immune system is important in understanding the pathophysiology of this pathogen. This knowledge is crucial for the development of therapeutic approaches that aim to clear staphylococcal infections.
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56
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Zheng Y, Shang W, Peng H, Rao Y, Zhao X, Hu Z, Yang Y, Hu Q, Tan L, Xiong K, Li S, Zhu J, Hu X, Zhou R, Li M, Rao X. Virulence Determinants Are Required for Brain Abscess Formation Through Staphylococcus aureus Infection and Are Potential Targets of Antivirulence Factor Therapy. Front Microbiol 2019; 10:682. [PMID: 31024479 PMCID: PMC6460967 DOI: 10.3389/fmicb.2019.00682] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/19/2019] [Indexed: 11/24/2022] Open
Abstract
Bacterial brain abscesses (BAs) are difficult to treat with conventional antibiotics. Thus, the development of alternative therapeutic strategies for BAs is of high priority. Identifying the virulence determinants that contribute to BA formation induced by Staphylococcus aureus would improve the effectiveness of interventions for this disease. In this study, RT-qPCR was performed to compare the expression levels of 42 putative virulence determinants of S. aureus strains Newman and XQ during murine BA formation, ear colonization, and bacteremia. The alterations in the expression levels of 23 genes were further confirmed through specific TaqMan RT-qPCR. Eleven S. aureus genes that persistently upregulated expression levels during BA infection were identified, and their functions in BA formation were confirmed through isogenic mutant experiments. Bacterial loads and BA volumes in mice infected with isdA, isdC, lgt, hla, or spa deletion mutants and the hla/spa double mutant strain were lower than those in mice infected with the wild-type Newman strain. The therapeutic application of monoclonal antibodies against Hla and SpA decreased bacterial loads and BA volume in mice infected with Newman. This study provides insights into the virulence determinants that contribute to staphylococcal BA formation and a paradigm for antivirulence factor therapy against S. aureus infections.
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Affiliation(s)
- Ying Zheng
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Weilong Shang
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Huagang Peng
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Yifan Rao
- Institute of Modern Biopharmaceuticals, School of Life Sciences, Southwest University, Chongqing, China
| | - Xia Zhao
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Zhen Hu
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Yi Yang
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Qiwen Hu
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Li Tan
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Kun Xiong
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Shu Li
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Junmin Zhu
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Xiaomei Hu
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Renjie Zhou
- Department of Emergency, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Ming Li
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
| | - Xiancai Rao
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University, Key Laboratory of Microbial Engineering under the Educational Committee in Chongqing, Chongqing, China
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Xie X, Lyu J, Hussain T, Li M. Drug Prevention and Control of Ventilator-Associated Pneumonia. Front Pharmacol 2019; 10:298. [PMID: 31001116 PMCID: PMC6455059 DOI: 10.3389/fphar.2019.00298] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 03/11/2019] [Indexed: 01/10/2023] Open
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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Triplett KD, Pokhrel S, Castleman MJ, Daly SM, Elmore BO, Joyner JA, Sharma G, Herbert G, Campen MJ, Hathaway HJ, Prossnitz ER, Hall PR. GPER activation protects against epithelial barrier disruption by Staphylococcus aureus α-toxin. Sci Rep 2019; 9:1343. [PMID: 30718654 PMCID: PMC6362070 DOI: 10.1038/s41598-018-37951-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 12/07/2018] [Indexed: 02/07/2023] Open
Abstract
Sex bias in innate defense against Staphylococcus aureus skin and soft tissue infection (SSTI) is dependent on both estrogen production by the host and S. aureus secretion of the virulence factor, α-hemolysin (Hla). The impact of estrogen signaling on the immune system is most often studied in terms of the nuclear estrogen receptors ERα and ERβ. However, the potential contribution of the G protein-coupled estrogen receptor (GPER) to innate defense against infectious disease, particularly with respect to skin infection, has not been addressed. Using a murine model of SSTI, we found that GPER activation with the highly selective agonist G-1 limits S. aureus SSTI and Hla-mediated pathogenesis, effects that were absent in GPER knockout mice. Specifically, G-1 reduced Hla-mediated skin lesion formation and pro-inflammatory cytokine production, while increasing bacterial clearance. In vitro, G-1 reduced surface expression of the Hla receptor, ADAM10, in a human keratinocyte cell line and increased resistance to Hla-mediated permeability barrier disruption. This novel role for GPER activation in skin innate defense against infectious disease suggests that G-1 may have clinical utility in patients with epithelial permeability barrier dysfunction or who are otherwise at increased risk of S. aureus infection, including those with atopic dermatitis or cancer.
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Affiliation(s)
- Kathleen D Triplett
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Srijana Pokhrel
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Moriah J Castleman
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Seth M Daly
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Bradley O Elmore
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Jason A Joyner
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Geetanjali Sharma
- University of New Mexico School of Medicine, Department of Internal Medicine, Albuquerque, NM, 87131, USA
| | - Guy Herbert
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Matthew J Campen
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA
| | - Helen J Hathaway
- University of New Mexico School of Medicine, Department of Cell Biology & Physiology, Albuquerque, NM, 87131, USA
| | - Eric R Prossnitz
- University of New Mexico School of Medicine, Department of Internal Medicine, Albuquerque, NM, 87131, USA
| | - Pamela R Hall
- University of New Mexico College of Pharmacy, Department of Pharmaceutical Sciences, Albuquerque, NM, 87131, USA.
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Divyakolu S, Chikkala R, Ratnakar KS, Sritharan V. Hemolysins of <i>Staphylococcus aureus</i>—An Update on Their Biology, Role in Pathogenesis and as Targets for Anti-Virulence Therapy. ACTA ACUST UNITED AC 2019. [DOI: 10.4236/aid.2019.92007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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60
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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: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [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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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: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [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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62
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Pharmacological Targeting of Pore-Forming Toxins as Adjunctive Therapy for Invasive Bacterial Infection. Toxins (Basel) 2018; 10:toxins10120542. [PMID: 30562923 PMCID: PMC6316385 DOI: 10.3390/toxins10120542] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 12/10/2018] [Accepted: 12/14/2018] [Indexed: 12/23/2022] Open
Abstract
For many of the most important human bacterial infections, invasive disease severity is fueled by the cell damaging and pro-inflammatory effects of secreted pore-forming toxins (PFTs). Isogenic PFT-knockout mutants, e.g., Staphylococcus aureus lacking α-toxin or Streptococcus pneumoniae deficient in pneumolysin, show attenuation in animal infection models. This knowledge has inspired multi-model investigations of strategies to neutralize PFTs or counteract their toxicity as a novel pharmacological approach to ameliorate disease pathogenesis in clinical disease. Promising examples of small molecule, antibody or nanotherapeutic drug candidates that directly bind and neutralize PFTs, block their oligomerization or membrane receptor interactions, plug establishment membrane pores, or boost host cell resiliency to withstand PFT action have emerged. The present review highlights these new concepts, with a special focus on β-PFTs produced by leading invasive human Gram-positive bacterial pathogens. Such anti-virulence therapies could be applied as an adjunctive therapy to antibiotic-sensitive and -resistant strains alike, and further could be free of deleterious effects that deplete the normal microflora.
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63
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Domenech M, Sempere J, de Miguel S, Yuste J. Combination of Antibodies and Antibiotics as a Promising Strategy Against Multidrug-Resistant Pathogens of the Respiratory Tract. Front Immunol 2018; 9:2700. [PMID: 30515172 PMCID: PMC6256034 DOI: 10.3389/fimmu.2018.02700] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 11/01/2018] [Indexed: 12/13/2022] Open
Abstract
The emergence of clinical isolates associated to multidrug resistance is a serious threat worldwide in terms of public health since complicates the success of the antibiotic treatment and the resolution of the infectious process. This is of great concern in pathogens affecting the lower respiratory tract as these infections are one of the major causes of mortality in children and adults. In most cases where the respiratory pathogen is associated to multidrug-resistance, antimicrobial concentrations both in serum and at the site of infection may be insufficient and the resolution of the infection depends on the interaction of the invading pathogen with the host immune response. The outcome of these infections largely depends on the susceptibility of the pathogen to the antibiotic treatment, although the humoral and cellular immune responses also play an important role in this process. Hence, prophylactic measures or even immunotherapy are alternatives against these multi-resistant pathogens. In this sense, specific antibodies and antibiotics may act concomitantly against the respiratory pathogen. Alteration of cell surface structures by antimicrobial drugs even at sub-inhibitory concentrations might result in greater exposure of microbial ligands that are normally hidden or hardly exposed. This alteration of the bacterial envelope may stimulate opsonization by natural and/or specific antibodies or even by host defense components, increasing the recognition of the microbial pathogen by circulating phagocytes. In this review we will explain the most relevant studies, where vaccination or the use of monoclonal antibodies in combination with antimicrobial treatment has demonstrated to be an alternative strategy to overcome the impact of multidrug resistance in respiratory pathogens.
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Affiliation(s)
- Mirian Domenech
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Julio Sempere
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Sara de Miguel
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Jose Yuste
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
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Jing C, Liu C, Liu F, Gao Y, Liu Y, Guan Z, Xuan B, Yu Y, Yang G. Novel human monoclonal antibodies targeting the F subunit of leukocidins reduce disease progression and mortality caused by Staphylococcus aureus. BMC Microbiol 2018; 18:181. [PMID: 30419818 PMCID: PMC6233355 DOI: 10.1186/s12866-018-1312-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 10/11/2018] [Indexed: 01/17/2023] Open
Abstract
Background Staphylococcus aureus is a leading cause of Gram-positive bacterial infections worldwide; however, the treatment of S. aureus infection has become increasingly difficult due to the prevalence of methicillin-resistant S. aureus strains, highlighting the urgent need for the development of novel strategies. The complexity of S. aureus pathogenesis relies on virulence factors. Recent studies have demonstrated that leukocidins expressed by the majority of clinical isolates play important roles in the pathogenesis of S. aureus. Results In this study, we developed three human monoclonal antibodies against all F-components of leukocidins HlgABC, LukSF, and LukED with high affinity. These antibodies were found to be capable of blocking leukocidin-mediated cell lysis in vitro. Furthermore, the antibodies dramatically reduced disease progression and mortality after S. aureus infection in vivo. Conclusions Our findings revealed that neutralizing bicomponent leukocidins may be a promising strategy to combat infections caused by S. aureus. Electronic supplementary material The online version of this article (10.1186/s12866-018-1312-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chendi Jing
- Department of Infectious Diseases, Peking University First Hospital, Beijing, 100034, China
| | - Chenghua Liu
- Beijing Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Fangjie Liu
- Beijing Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Yaping Gao
- Beijing Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Yu Liu
- Beijing Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Zhangchun Guan
- Beijing Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Bo Xuan
- Beijing Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Yanyan Yu
- Department of Infectious Diseases, Peking University First Hospital, Beijing, 100034, China.
| | - Guang Yang
- Beijing Institute of Basic Medical Sciences, Beijing, 100850, China. .,State Key Laboratory of Toxicology and Medical Countermeasures, Beijing, China.
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Zhou K, Li C, Chen D, Pan Y, Tao Y, Qu W, Liu Z, Wang X, Xie S. A review on nanosystems as an effective approach against infections of Staphylococcus aureus. Int J Nanomedicine 2018; 13:7333-7347. [PMID: 30519018 PMCID: PMC6233487 DOI: 10.2147/ijn.s169935] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Staphylococcus aureus (S. aureus) is an important zoonotic bacteria and hazardous for the health of human beings and livestock globally. The characteristics like biofilm forming, facultative intracellular survival, and growing resistance of S. aureus pose a great challenge to its use in therapy. Nanoparticles are considered as a promising way to overcome the infections’ therapeutic problems caused by S. aureus. In this paper, the present progress and challenges of nanoparticles in the treatment of S. aureus infection are focused on stepwise. First, the survival and infection mechanism of S. aureus are analyzed. Second, the treatment challenges posed by S. aureus are provided, which is followed by the third step including the advantages of nanoparticles in improving the penetration and accumulation ability of their payload antibiotics into cell, inhibiting S. aureus biofilm formation, and enhancing the antibacterial activity against resistant isolates. Finally, the challenges and future perspective of nanoparticles for S. aureus infection therapy are introduced. This review will help the readers to realize that the nanosystems can effectively fight against the S. aureus infection by inhibiting biofilm formation, enhancing intracellular delivery, and improving activity against methicillin-resistant S. aureus and small colony variant phenotypes as well as aim to help researchers looking for more efficient nano-systems to combat the S. aureus infections.
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Affiliation(s)
- Kaixiang Zhou
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China,
| | - Chao Li
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China,
| | - Dongmei Chen
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Wuhan, Hubei, China
| | - Yuanhu Pan
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China,
| | - Yanfei Tao
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Wuhan, Hubei, China
| | - Wei Qu
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Wuhan, Hubei, China
| | - Zhenli Liu
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Wuhan, Hubei, China
| | - Xiaofang Wang
- Animal Husbandry and Veterinary Institute of Hebei Province, Baoding, Hebei, China,
| | - Shuyu Xie
- MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei, China,
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66
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Alanine Scanning Mutagenesis of the MEDI4893 (Suvratoxumab) Epitope Reduces Alpha Toxin Lytic Activity In Vitro and Staphylococcus aureus Fitness in Infection Models. Antimicrob Agents Chemother 2018; 62:AAC.01033-18. [PMID: 30150481 PMCID: PMC6201083 DOI: 10.1128/aac.01033-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 08/18/2018] [Indexed: 02/06/2023] Open
Abstract
Alpha toxin (AT) is a cytolytic pore-forming toxin that plays a key role in Staphylococcus aureus pathogenesis; consequently, extensive research was undertaken to understand the AT mechanism of action and its utility as a target for novel prophylaxis and treatment strategies against S. aureus infections. MEDI4893 (suvratoxumab) is a human anti-AT IgG1 monoclonal antibody (MAb) that targets AT and is currently in phase 2 clinical development. Alpha toxin (AT) is a cytolytic pore-forming toxin that plays a key role in Staphylococcus aureus pathogenesis; consequently, extensive research was undertaken to understand the AT mechanism of action and its utility as a target for novel prophylaxis and treatment strategies against S. aureus infections. MEDI4893 (suvratoxumab) is a human anti-AT IgG1 monoclonal antibody (MAb) that targets AT and is currently in phase 2 clinical development. As shown previously, the MEDI4893-binding epitope on AT is comprised of the highly conserved amino acid regions 177 to 200 and 261 to 271, suggesting these amino acids are important for AT function. To test this hypothesis and gain insight into the effect of mutations in the epitope on AT neutralization by MEDI4893, nine MEDI4893 contact residues in AT were individually mutated to alanine. Consistent with our hypothesis, 8 out of 9 mutants exhibited >2-fold loss in lytic activity resulting from a defect in cell binding and pore formation. MEDI4893 binding affinity was reduced >2-fold (2- to 27-fold) for 7 out of 9 mutants, and no binding was detected for the W187A mutant. MEDI4893 effectively neutralized all of the lytic mutants in vitro and in vivo. When the defective mutants were introduced into an S. aureus clinical isolate, the mutant-expressing strains exhibited less severe disease in mouse models and were effectively neutralized by MEDI4893. These results indicate the MEDI4893 epitope is highly conserved due in part to its role in AT pore formation and bacterial fitness, thereby decreasing the likelihood for the emergence of MAb-resistant variants.
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Aslam B, Wang W, Arshad MI, Khurshid M, Muzammil S, Rasool MH, Nisar MA, Alvi RF, Aslam MA, Qamar MU, Salamat MKF, Baloch Z. Antibiotic resistance: a rundown of a global crisis. Infect Drug Resist 2018; 11:1645-1658. [PMID: 30349322 PMCID: PMC6188119 DOI: 10.2147/idr.s173867] [Citation(s) in RCA: 1177] [Impact Index Per Article: 196.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The advent of multidrug resistance among pathogenic bacteria is imperiling the worth of antibiotics, which have previously transformed medical sciences. The crisis of antimicrobial resistance has been ascribed to the misuse of these agents and due to unavailability of newer drugs attributable to exigent regulatory requirements and reduced financial inducements. Comprehensive efforts are needed to minimize the pace of resistance by studying emergent microorganisms, resistance mechanisms, and antimicrobial agents. Multidisciplinary approaches are required across health care settings as well as environment and agriculture sectors. Progressive alternate approaches including probiotics, antibodies, and vaccines have shown promising results in trials that suggest the role of these alternatives as preventive or adjunct therapies in future.
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Affiliation(s)
- Bilal Aslam
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Wei Wang
- NHC Key Laboratory of Food Safety Risk Assessment, China National Center for Food Safety Risk Assessment, Beijing, China
| | - Muhammad Imran Arshad
- Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Mohsin Khurshid
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan.,College of Allied Health Professionals, Directorate of Medical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Saima Muzammil
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | | | - Muhammad Atif Nisar
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Ruman Farooq Alvi
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Muhammad Aamir Aslam
- Institute of Microbiology, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Muhammad Usman Qamar
- Department of Microbiology, Government College University Faisalabad, Faisalabad, Pakistan
| | | | - Zulqarnain Baloch
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China,
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68
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Askarian F, Wagner T, Johannessen M, Nizet V. Staphylococcus aureus modulation of innate immune responses through Toll-like (TLR), (NOD)-like (NLR) and C-type lectin (CLR) receptors. FEMS Microbiol Rev 2018; 42:656-671. [PMID: 29893825 PMCID: PMC6098222 DOI: 10.1093/femsre/fuy025] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 06/07/2018] [Indexed: 02/07/2023] Open
Abstract
Early recognition of pathogens by the innate immune system is crucial for bacterial clearance. Many pattern recognition receptors (PRRs) such as Toll-like (TLRs) and (NOD)-like (NLRs) receptors have been implicated in initial sensing of bacterial components. The intracellular signaling cascades triggered by these receptors result in transcriptional upregulation of inflammatory pathways. Although this step is crucial for bacterial elimination, it is also associated with the potential for substantial immunopathology, which underscores the need for tight control of inflammatory responses. The leading human bacterial pathogen Staphylococcus aureus expresses over 100 virulence factors that exert numerous effects upon host cells. In this manner, the pathogen seeks to avoid host recognition or perturb PRR-induced innate immune responses to allow optimal survival in the host. These immune system interactions may result in enhanced bacterial proliferation but also provoke systemic cytokine responses associated with sepsis. This review summarizes recent findings on the various mechanisms applied by S. aureus to modulate or interfere with inflammatory responses through PRRs. Detailed understanding of these complex interactions can provide new insights toward future immune-stimulatory therapeutics against infection or immunomodulatory therapeutics to suppress or correct dysregulated inflammation.
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Affiliation(s)
- Fatemeh Askarian
- Research Group of Host Microbe Interaction, Faculty of Health Sciences, UiT-The Arctic University of Norway, 9037 Tromsø, Norway
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, UC San Diego, La Jolla, CA 92093, USA
| | - Theresa Wagner
- Research Group of Host Microbe Interaction, Faculty of Health Sciences, UiT-The Arctic University of Norway, 9037 Tromsø, Norway
| | - Mona Johannessen
- Research Group of Host Microbe Interaction, Faculty of Health Sciences, UiT-The Arctic University of Norway, 9037 Tromsø, Norway
| | - Victor Nizet
- Division of Host-Microbe Systems & Therapeutics, Department of Pediatrics, UC San Diego, La Jolla, CA 92093, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, UC San Diego, La Jolla, CA 92093, USA
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69
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Nagy E, Nagy G, Power CA, Badarau A, Szijártó V. Anti-bacterial Monoclonal Antibodies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1053:119-153. [PMID: 29549638 DOI: 10.1007/978-3-319-72077-7_7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The failing efficacy of antibiotics and the high mortality rate among high-risk patients calls for new treatment modalities for bacterial infections. Due to the vastly divergent pathogenesis of human pathogens, each microbe requires a tailored approach. The main modes of action of anti-bacterial antibodies are virulence factor neutralization, complement-mediated bacterial lysis and enhancement of opsonophagocytic uptake and killing (OPK). Gram-positive bacteria cannot be lysed by complement and their pathogenesis often involves secreted toxins, therefore typically toxin-neutralization and OPK activity are required to prevent and ameliorate disease. In fact, the success stories in terms of approved products, in the anti-bacterial mAb field are based on toxin neutralization (Bacillus anthracis, Clostridium difficile). In contrast, Gram-negative bacteria are vulnerable to antibody-dependent complement-mediated lysis, while their pathogenesis rarely relies on secreted exotoxins, and involves the pro-inflammatory endotoxin (lipopolysaccharide). Given the complexity of bacterial pathogenesis, antibody therapeutics are expected to be most efficient upon targeting more than one virulence factor and/or combining different modes of action. The improved understanding of bacterial pathogenesis combined with the versatility and maturity of antibody discovery technologies available today are pivotal for the design of novel anti-bacterial therapeutics. The intensified research generating promising proof-of-concept data, and the increasing number of clinical programs with anti-bacterial mAbs, indicate that the field is ready to fulfill its promise in the coming years.
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Affiliation(s)
- Eszter Nagy
- Arsanis Biosciences GmbH/Arsanis, Inc, Vienna, Austria.
| | - Gábor Nagy
- Arsanis Biosciences GmbH/Arsanis, Inc, Vienna, Austria
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70
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Gonçalves MC, Horewicz VV, Lückemeyer DD, Prudente AS, Assreuy J. Experimental Sepsis Severity Score Associated to Mortality and Bacterial Spreading is Related to Bacterial Load and Inflammatory Profile of Different Tissues. Inflammation 2018; 40:1553-1565. [PMID: 28567497 DOI: 10.1007/s10753-017-0596-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Pneumonia-induced sepsis is responsible for about 50% of cases in the world. Patients who develop severe sepsis and septic shock present organ dysfunction and elevated plasma cytokine levels, which may lead to death. Clinical scores are important to evaluate the framework of septic patients and are used to predict the syndrome progress, prognostics, and mortality. The objective of the present study was to verify the applicability of a murine clinical score system to experimental sepsis (pneumonia-induced sepsis in male mice) and to correlate it with mortality and bacterial dissemination in different organs. Results demonstrated that animals which present higher clinical scores (>3) are more likely to die. Animals presenting high clinical scores exhibited transient bacteremia and displayed bacterial spreading to different organs such as heart, kidney, liver, and brain. There is a correlation between clinical score and bacterial dissemination and consequently greater risk of death. In addition, animals which showed bacterial dissemination in more than three organs and high clinical scores presented high levels of cytokines (TNF-α, MCP-1, IL-6, and IL-10) in plasma, lung, heart, liver, kidney, and brain. Therefore, our study suggests that (1) severity scores have predictive power in experimental models of sepsis and (2) high concentrations of tissue cytokines may contribute to localized inflammation and be one of the factors responsible for the systemic inflammatory syndrome of sepsis.
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Affiliation(s)
- Muryel Carvalho Gonçalves
- Department of Pharmacology, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Verônica Vargas Horewicz
- Department of Pharmacology, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Débora Denardin Lückemeyer
- Department of Pharmacology, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Arthur Silveira Prudente
- Department of Pharmacology, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Jamil Assreuy
- Department of Pharmacology, Center of Biological Sciences, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil. .,Department of Pharmacology, Block D/CCB, Universidade Federal de Santa Catarina, Florianópolis, SC, 88040-900, Brazil.
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71
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Yang H, Xu J, Li W, Wang S, Li J, Yu J, Li Y, Wei H. Staphylococcus aureus virulence attenuation and immune clearance mediated by a phage lysin-derived protein. EMBO J 2018; 37:embj.201798045. [PMID: 30037823 DOI: 10.15252/embj.201798045] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 06/20/2018] [Accepted: 06/27/2018] [Indexed: 01/04/2023] Open
Abstract
New anti-infective approaches are much needed to control multi-drug-resistant (MDR) pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA). Here, we found for the first time that a recombinant protein derived from the cell wall binding domain (CBD) of the bacteriophage lysin PlyV12, designated as V12CBD, could attenuate S. aureus virulence and enhance host immune defenses via multiple manners. After binding with V12CBD, S. aureus became less invasive to epithelial cells and more susceptible to macrophage killing. The expressions of multiple important virulence genes of S. aureus were reduced 2.4- to 23.4-fold as response to V12CBD More significantly, V12CBD could activate macrophages through NF-κB pathway and enhance phagocytosis against S. aureus As a result, good protections of the mice from MRSA infections were achieved in therapeutic and prophylactic models. These unique functions of V12CBD would render it a novel alternative molecule to control MDRS. aureus infections.
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Affiliation(s)
- Hang Yang
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Jingjing Xu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Wuyou Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Shujuan Wang
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Junhua Li
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Junping Yu
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Yuhong Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Hongping Wei
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
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Surewaard BGJ, Thanabalasuriar A, Zeng Z, Tkaczyk C, Cohen TS, Bardoel BW, Jorch SK, Deppermann C, Bubeck Wardenburg J, Davis RP, Jenne CN, Stover KC, Sellman BR, Kubes P. α-Toxin Induces Platelet Aggregation and Liver Injury during Staphylococcus aureus Sepsis. Cell Host Microbe 2018; 24:271-284.e3. [PMID: 30033122 DOI: 10.1016/j.chom.2018.06.017] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 05/15/2018] [Accepted: 06/27/2018] [Indexed: 01/09/2023]
Abstract
During sepsis, small blood vessels can become occluded by large platelet aggregates of poorly understood etiology. During Staphylococcal aureus infection, sepsis severity is linked to the bacterial α-toxin (α-hemolysin, AT) through unclear mechanisms. In this study, we visualized intravascular events in the microcirculation and found that intravenous AT injection induces rapid platelet aggregation, forming dynamic micro-thrombi in the microcirculation. These aggregates are retained in the liver sinusoids and kidney glomeruli, causing multi-organ dysfunction. Acute staphylococcal infection results in sequestration of most bacteria by liver macrophages. Platelets are initially recruited to these macrophages and help eradicate S. aureus. However, at later time points, AT causes aberrant and damaging thrombosis throughout the liver. Treatment with an AT neutralizing antibody (MEDI4893∗) prevents platelet aggregation and subsequent liver damage, without affecting the initial and beneficial platelet recruitment. Thus, AT neutralization may represent a promising approach to combat staphylococcal-induced intravascular coagulation and organ dysfunction.
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Affiliation(s)
- Bas G J Surewaard
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada; Department of Medical Microbiology, University Medical Center, Utrecht, the Netherlands
| | - Ajitha Thanabalasuriar
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| | - Zhutian Zeng
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| | - Christine Tkaczyk
- Department of Microbial Sciences, Medimmune, LLC, Gaithersburg, MD, USA
| | - Taylor S Cohen
- Department of Microbial Sciences, Medimmune, LLC, Gaithersburg, MD, USA
| | - Bart W Bardoel
- Department of Medical Microbiology, University Medical Center, Utrecht, the Netherlands
| | - Selina K Jorch
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| | - Carsten Deppermann
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| | - Juliane Bubeck Wardenburg
- Department of Pediatrics and Division of Pediatric Critical Care Medicine at Washington University School of Medicine, St. Louis, MO, USA
| | - Rachelle P Davis
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada; Department of Microbiology, Immunology and Infectious Disease, University of Calgary, Calgary, AB, Canada
| | - Craig N Jenne
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada; Department of Microbiology, Immunology and Infectious Disease, University of Calgary, Calgary, AB, Canada
| | - Kendall C Stover
- Department of Microbial Sciences, Medimmune, LLC, Gaithersburg, MD, USA
| | - Bret R Sellman
- Department of Microbial Sciences, Medimmune, LLC, Gaithersburg, MD, USA
| | - Paul Kubes
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada.
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Jatana S, Homer CR, Madajka M, Ponti AK, Kabi A, Papay F, McDonald C. Pyrimidine synthesis inhibition enhances cutaneous defenses against antibiotic resistant bacteria through activation of NOD2 signaling. Sci Rep 2018; 8:8708. [PMID: 29880914 PMCID: PMC5992176 DOI: 10.1038/s41598-018-27012-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 05/23/2018] [Indexed: 12/13/2022] Open
Abstract
Multidrug-resistant bacterial strains are a rapidly emerging healthcare threat; therefore it is critical to develop new therapies to combat these organisms. Prior antibacterial strategies directly target pathogen growth or viability. Host-directed strategies to increase antimicrobial defenses may be an effective alternative to antibiotics and reduce development of resistant strains. In this study, we demonstrated the efficacy of a pyrimidine synthesis inhibitor, N-phosphonacetyl-L-aspartate (PALA), to enhance clearance of methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Acinetobacter baumannii strains by primary human dermal fibroblasts in vitro. PALA did not have a direct bactericidal effect, but enhanced cellular secretion of the antimicrobial peptides human β-defensin 2 (HBD2) and HBD3 from fibroblasts. When tested in porcine and human skin explant models, a topical PALA formulation was efficacious to enhance MRSA, P. aeruginosa, and A. baumannii clearance. Topical PALA treatment of human skin explants also resulted in increased HBD2 and cathelicidin (LL-37) production. The antimicrobial actions of PALA required expression of nucleotide-binding, oligomerization domain 2 (NOD2), receptor-interacting serine/threonine-protein kinase 2 (RIP2), and carbamoyl phosphatase synthase II/aspartate transcarbamylase/dihydroorotase (CAD). Our results indicate that PALA may be a new option to combat multidrug-resistant bacterial infections of the skin through enhancement of an integral pathway of the cutaneous innate immune defense system.
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Affiliation(s)
- Samreen Jatana
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Craig R Homer
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Maria Madajka
- Department of Plastic Surgery, Dermatology and Plastic Surgery Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - András K Ponti
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Amrita Kabi
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Francis Papay
- Department of Plastic Surgery, Dermatology and Plastic Surgery Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Christine McDonald
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio, USA.
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75
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MEDI3902 Correlates of Protection against Severe Pseudomonas aeruginosa Pneumonia in a Rabbit Acute Pneumonia Model. Antimicrob Agents Chemother 2018; 62:AAC.02565-17. [PMID: 29483116 PMCID: PMC5923159 DOI: 10.1128/aac.02565-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/20/2018] [Indexed: 12/24/2022] Open
Abstract
Pseudomonas aeruginosa is among the most formidable antibiotic-resistant pathogens and is a leading cause of hospital-associated infections. With dwindling options for antibiotic-resistant infections, a new paradigm for treatment and disease resolution is required. MEDI3902, a bispecific antibody targeting the P. aeruginosa type III secretion (T3S) protein PcrV and Psl exopolysaccharide, was previously shown to mediate potent protective activity in murine infection models. With the current challenges associated with the clinical development of narrow-spectrum agents, robust preclinical efficacy data in multiple animal species are desirable. Here, we sought to develop a rabbit P. aeruginosa acute pneumonia model to further evaluate the activity of MEDI3902 intervention. In the rabbit model of acute pneumonia, prophylaxis with MEDI3902 exhibited potent dose-dependent protection, whereas those receiving control IgG developed fatal hemorrhagic necrotizing pneumonia between 12 and 54 h after infection. Blood biomarkers (e.g., partial pressure of oxygen [pO2], partial pressure of carbon dioxide [pCO2], base excess, lactate, and creatinine) were grossly deranged for the vast majority of control IgG-treated animals but remained within normal limits for MEDI3902-treated animals. In addition, MEDI3902-treated animals exhibited a profound reduction in P. aeruginosa organ burden and a marked reduction in the expression of proinflammatory mediators from lung tissue, which correlated with reduced lung histopathology. These results confirm that targeting PcrV and Psl via MEDI3902 is a promising candidate for immunotherapy against P. aeruginosa pneumonia.
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Alpha-Toxin Contributes to Biofilm Formation among Staphylococcus aureus Wound Isolates. Toxins (Basel) 2018; 10:toxins10040157. [PMID: 29659477 PMCID: PMC5923323 DOI: 10.3390/toxins10040157] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2018] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 01/03/2023] Open
Abstract
Biofilms complicate treatment of Staphylococcus aureus (SA) wound infections. Previously, we determined alpha-toxin (AT)-promoted SA biofilm formation on mucosal tissue. Therefore, we evaluated SA wound isolates for AT production and biofilm formation on epithelium and assessed the role of AT in biofilm formation. Thirty-eight wound isolates were molecularly typed by pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (ST), and spa typing. We measured biofilm formation of these SA isolates in vitro and ex vivo and quantified ex vivo AT production. We also investigated the effect of an anti-AT monoclonal antibody (MEDI4893*) on ex vivo biofilm formation by methicillin-resistant SA (USA 300 LAC) and tested whether purified AT rescued the biofilm defect of hla mutant SA strains. The predominant PFGE/ST combinations were USA100/ST5 (50%) and USA300/ST8 (33%) for methicillin-resistant SA (MRSA, n = 18), and USA200/ST30 (20%) for methicillin-susceptible SA (MSSA, n = 20). Ex vivo AT production correlated significantly with ex vivo SA wound isolate biofilm formation. Anti-alpha-toxin monoclonal antibody (MEDI4893*) prevented ex vivo biofilm formation by MRSA USA300 strain LAC. Wild-type AT rescued the ex vivo biofilm defect of non-AT producing SA strains. These findings provide evidence that AT plays a role in SA biofilm formation on epithelial surfaces and suggest that neutralization of AT may be useful in preventing and treating SA infections.
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Speziale P, Rindi S, Pietrocola G. Antibody-Based Agents in the Management of Antibiotic-Resistant Staphylococcus aureus Diseases. Microorganisms 2018. [PMID: 29533985 PMCID: PMC5874639 DOI: 10.3390/microorganisms6010025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Staphylococcus aureus is a human pathogen that can cause a wide spectrum of diseases, including sepsis, pneumonia, arthritis, and endocarditis. Ineffective treatment of a number of staphylococcal infections with antibiotics is due to the development and spread of antibiotic-resistant strains following decades of antibiotic usage. This has generated renewed interest within the scientific community in alternative therapeutic agents, such as anti-S. aureus antibodies. Although the role of antibodies in the management of S. aureus diseases is controversial, the success of this pathogen in neutralizing humoral immunity clearly indicates that antibodies offer the host extensive protection. In this review, we report an update on efforts to develop antibody-based agents, particularly monoclonal antibodies, and their therapeutic potential in the passive immunization approach to the treatment and prevention of S. aureus infections.
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Affiliation(s)
- Pietro Speziale
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy.
- Department of Industrial and Information Engineering, University of Pavia, 27100 Pavia, Italy.
| | - Simonetta Rindi
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy.
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78
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Tan L, Li SR, Jiang B, Hu XM, Li S. Therapeutic Targeting of the Staphylococcus aureus Accessory Gene Regulator ( agr) System. Front Microbiol 2018; 9:55. [PMID: 29422887 PMCID: PMC5789755 DOI: 10.3389/fmicb.2018.00055] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 01/10/2018] [Indexed: 11/19/2022] Open
Abstract
Staphylococcus aureus can cause numerous different diseases, which has been attributed to its large repertoire of virulence factors, many of which are under the control of the accessory gene regulator (agr) quorum sensing system. Under conditions of high cell density, agr increases the production of many virulence factors, decreases expression of several colonization factors, and is intimately associated with the pathogenesis and biofilm formation of S. aureus. This review summarizes our current understanding of the molecular mechanisms underlying agr quorum sensing and the regulation of agr expression. The discussion also examines subgroups of agr and their association with different diseases, and concludes with an analysis of strategies for designing drugs and vaccines that target agr to combat S. aureus infections.
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Affiliation(s)
- Li Tan
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China
| | - Si Rui Li
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China
| | - Bei Jiang
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China
| | - Xiao Mei Hu
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China
| | - Shu Li
- Department of Microbiology, College of Basic Medical Sciences, Third Military Medical University, Chongqing, China
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79
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Ruzin A, Wu Y, Yu L, Yu XQ, Tabor DE, Mok H, Tkaczyk C, Jensen K, Bellamy T, Roskos L, Esser MT, Jafri HS. Characterisation of anti-alpha toxin antibody levels and colonisation status after administration of an investigational human monoclonal antibody, MEDI4893, against Staphylococcus aureus alpha toxin. Clin Transl Immunology 2018; 7:e1009. [PMID: 29484186 PMCID: PMC5822409 DOI: 10.1002/cti2.1009] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 12/20/2017] [Accepted: 12/29/2017] [Indexed: 01/07/2023] Open
Abstract
Objectives MEDI4893 is a novel, long‐acting human monoclonal antibody targeting Staphylococcus aureus (SA) alpha toxin (AT). This report presents the results of the exploratory analyses from a randomised phase 1 dose‐escalation study in healthy human subjects receiving single intravenous MEDI4893 doses or placebo. Methods Anti‐AT antibodies and AT expression were measured as described previously. Nasal swabs were analysed by culture and PCR. Data were summarised by treatment groups and visits by using SAS System Version 9.3. Results Subjects receiving 2250 or 5000 mg of MEDI4893 had the highest serum anti‐AT neutralising antibody (NAb) levels: approximately 180‐ to 240‐, 70‐ to 100‐ and sevenfold to 10‐fold higher than respective baseline levels at peak, 30 and 360 days, respectively. In these subjects, levels of serum anti‐AT NAbs were >3.2 International Units (IU) mL−1 for at least 211 days. In the upper respiratory tract, anti‐AT NAb levels increased with MEDI4893 dose. No apparent effect of MEDI4893 on SA nasal colonisation, hla gene sequence or AT expression was observed. Five AT variants were detected, their lytic activity was fully neutralised by MEDI4893. Discussion Our results indicate that (1) MEDI4893 administration at 2250 and 5000 mg would provide effective immunoprophylaxis against systemic SA disease; (2) MEDI4983 distributes to the upper respiratory tract and retains neutralising activity against AT; and (3) potential for emergence of MEDI4893 resistance is low. Conclusion Intravenous administration of MEDI4893 maintained levels of anti‐AT NAbs in serum and nasal mucosa that may provide effective immunoprophylaxis against SA disease and support continued clinical development of MEDI4893.
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Affiliation(s)
| | | | - Li Yu
- MedImmune Gaithersburg MD USA
| | - Xiang-Qing Yu
- MedImmune Gaithersburg MD USA.,Present address: Janssen Pharmaceuticals, Inc. Johnson & Johnson Spring House PA USA
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80
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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: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [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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81
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Kane TL, Carothers KE, Lee SW. Virulence Factor Targeting of the Bacterial Pathogen Staphylococcus aureus for Vaccine and Therapeutics. Curr Drug Targets 2018; 19:111-127. [PMID: 27894236 PMCID: PMC5957279 DOI: 10.2174/1389450117666161128123536] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/12/2016] [Accepted: 10/27/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND Staphylococcus aureus is a major bacterial pathogen capable of causing a range of infections in humans from gastrointestinal disease, skin and soft tissue infections, to severe outcomes such as sepsis. Staphylococcal infections in humans can be frequent and recurring, with treatments becoming less effective due to the growing persistence of antibiotic resistant S. aureus strains. Due to the prevalence of antibiotic resistance, and the current limitations on antibiotic development, an active and highly promising avenue of research has been to develop strategies to specifically inhibit the activity of virulence factors produced S. aureus as an alternative means to treat disease. OBJECTIVE In this review we specifically highlight several major virulence factors produced by S. aureus for which recent advances in antivirulence approaches may hold promise as an alternative means to treating diseases caused by this pathogen. Strategies to inhibit virulence factors can range from small molecule inhibitors, to antibodies, to mutant and toxoid forms of the virulence proteins. CONCLUSION The major prevalence of antibiotic resistant strains of S. aureus combined with the lack of new antibiotic discoveries highlight the need for vigorous research into alternative strategies to combat diseases caused by this highly successful pathogen. Current efforts to develop specific antivirulence strategies, vaccine approaches, and alternative therapies for treating severe disease caused by S. aureus have the potential to stem the tide against the limitations that we face in the post-antibiotic era.
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Affiliation(s)
- Trevor L. Kane
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Katelyn E. Carothers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Shaun W. Lee
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
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82
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Rouha H, Weber S, Janesch P, Maierhofer B, Gross K, Dolezilkova I, Mirkina I, Visram ZC, Malafa S, Stulik L, Badarau A, Nagy E. Disarming Staphylococcus aureus from destroying human cells by simultaneously neutralizing six cytotoxins with two human monoclonal antibodies. Virulence 2017; 9:231-247. [PMID: 29099326 PMCID: PMC5955178 DOI: 10.1080/21505594.2017.1391447] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Pathogenesis of Staphylococcus aureus is increasingly recognized to be driven by powerful toxins. Staphylococcus aureus employs up to six pore-forming toxins to subvert the human host defense and to promote bacterial invasion: alpha-hemolysin that disrupts epithelial and endothelial barriers and five leukocidins that lyse phagocytes involved in bacterial clearance. Previously, we described two human monoclonal antibodies (mAbs), ASN-1 that neutralizes alpha-hemolysin and four leukocidins (LukSF-PV, LukED, HlgAB, HlgCB), and ASN-2 that inactivates the 5th leukocidin, LukGH. In this study we tested the individual and combined effects of ASN-1 and ASN-2 in multiple in vitro models employing relevant human target cells. We found that diverse S. aureus isolates with different genetic backgrounds (based on MLST- and spa-typing) and antibiotic sensitivity (both MRSA and MSSA) displayed greatly different cytotoxin expression patterns influenced by the type of growth medium used. Both mAbs were required to fully prevent the lysis of human neutrophils exposed to the mixture of recombinant cytotoxins or native toxins present in the culture supernatants of S. aureus isolates. Flow cytometry confirmed the protective effects of ASN-1 + ASN-2 (known as ASN100) on granulocytes, monocytes, NK-cells and T-lymphocytes. ASN-1 alone preserved the integrity of a 3D-primary culture of human tracheal/bronchial mucociliary epithelial tissue infected with S. aureus. We conclude that simultaneous inhibition of alpha-hemolysin and five leukocidins by ASN100 blocks cytolytic activity of S. aureus towards human target cells in vitro.
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Affiliation(s)
- Harald Rouha
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Susanne Weber
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Philipp Janesch
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Barbara Maierhofer
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Karin Gross
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Ivana Dolezilkova
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Irina Mirkina
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Zehra C Visram
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Stefan Malafa
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Lukas Stulik
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Adriana Badarau
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
| | - Eszter Nagy
- a Arsanis Biosciences, Helmut-Qualtinger-Gasse 2, Campus Vienna Biocenter , Vienna , Austria
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83
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Immune stealth-driven O2 serotype prevalence and potential for therapeutic antibodies against multidrug resistant Klebsiella pneumoniae. Nat Commun 2017; 8:1991. [PMID: 29222409 PMCID: PMC5722860 DOI: 10.1038/s41467-017-02223-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 11/14/2017] [Indexed: 12/21/2022] Open
Abstract
Emerging multidrug-resistant bacteria are a challenge for modern medicine, but how these pathogens are so successful is not fully understood. Robust antibacterial vaccines have prevented and reduced resistance suggesting a pivotal role for immunity in deterring antibiotic resistance. Here, we show the increased prevalence of Klebsiella pneumoniae lipopolysaccharide O2 serotype strains in all major drug resistance groups correlating with a paucity of anti-O2 antibodies in human B cell repertoires. We identify human monoclonal antibodies to O-antigens that are highly protective in mouse models of infection, even against heavily encapsulated strains. These antibodies, including a rare anti-O2 specific antibody, synergistically protect against drug-resistant strains in adjunctive therapy with meropenem, a standard-of-care antibiotic, confirming the importance of immune assistance in antibiotic therapy. These findings support an antibody-based immunotherapeutic strategy even for highly resistant K. pneumoniae infections, and underscore the effect humoral immunity has on evolving drug resistance. Therapeutics to combat multidrug-resistant bacteria such as Klebsiella pneumoniae are needed. Here the authors show immune evasion drives lipopolysaccharide O2 serotype expansion in multidrug-resistant isolates, and anti-O-antigen human monoclonal antibodies synergize with antibiotics to protect mice from infection.
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84
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Azeredo da Silveira S, Perez A. Improving the fate of severely infected patients: the promise of anti-toxin treatments and superiority trials. Expert Rev Anti Infect Ther 2017; 15:973-975. [DOI: 10.1080/14787210.2017.1400908] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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85
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Karau MJ, Tilahun ME, Krogman A, Osborne BA, Goldsby RA, David CS, Mandrekar JN, Patel R, Rajagopalan G. Passive therapy with humanized anti-staphylococcal enterotoxin B antibodies attenuates systemic inflammatory response and protects from lethal pneumonia caused by staphylococcal enterotoxin B-producing Staphylococcus aureus. Virulence 2017; 8:1148-1159. [PMID: 27925510 PMCID: PMC5711449 DOI: 10.1080/21505594.2016.1267894] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 11/21/2016] [Accepted: 11/28/2016] [Indexed: 02/08/2023] Open
Abstract
Drugs such as linezolid that inhibit bacterial protein synthesis may be beneficial in treating infections caused by toxigenic Staphylococcus aureus. As protein synthesis inhibitors have no effect on preformed toxins, neutralization of pathogenic exotoxins with anti-toxin antibodies may be beneficial in conjunction with antibacterial therapy. Herein, we evaluated the efficacy of human-mouse chimeric high-affinity neutralizing anti-staphylococcal enterotoxin B (SEB) antibodies in the treatment of experimental pneumonia caused by SEB-producing S. aureus. Since HLA class II transgenic mice mount a stronger systemic immune response following challenge with SEB and are more susceptible to SEB-induced lethal toxic shock than conventional mice strains, HLA-DR3 transgenic mice were used. Lethal pneumonia caused by SEB-producing S. aureus in HLA-DR3 transgenic mice was characterized by robust T cell activation and elevated systemic levels of several pro-inflammatory cytokines and chemokines. Prophylactic administration of a single dose of linezolid 30 min prior to the onset of infection attenuated the systemic inflammatory response and protected from mortality whereas linezolid administered 60 min after the onset of infection failed to confer significant protection. Human-mouse chimeric high-affinity neutralizing anti-SEB antibodies alone, but not polyclonal human IgG, mitigated this response and protected from death when administered immediately after initiation of infection. Further, anti-SEB antibodies as well as intact polyclonal human IgG, but not its Fab or Fc fragments, protected from lethal pneumonia when followed with linezolid therapy 60 min later. In conclusion, neutralization of superantigens with high-affinity antibodies may have beneficial effects in pneumonia.
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Affiliation(s)
- Melissa J. Karau
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Mulualem E. Tilahun
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, USA
- Department of Biology, Amherst College, Amherst, MA, USA
| | - Ashton Krogman
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Barbara A. Osborne
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, USA
| | | | - Chella S. David
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Jayawant N. Mandrekar
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Robin Patel
- Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, MN, USA
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Govindarajan Rajagopalan
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic College of Medicine, Rochester, MN, USA
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86
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Paling FP, Troeman DPR, Wolkewitz M, Kalyani R, Prins DR, Weber S, Lammens C, Timbermont L, Goossens H, Malhotra-Kumar S, Sifakis F, Bonten MJM, Kluytmans JAJW. Rationale and design of ASPIRE-ICU: a prospective cohort study on the incidence and predictors of Staphylococcus aureus and Pseudomonas aeruginosa pneumonia in the ICU. BMC Infect Dis 2017; 17:643. [PMID: 28946849 PMCID: PMC5613521 DOI: 10.1186/s12879-017-2739-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 09/14/2017] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND The epidemiology of ICU pneumonia caused by Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) is not fully described, but is urgently needed to support the development of effective interventions. The objective of this study is to estimate the incidence of S. aureus and P. aeruginosa ICU pneumonia and to assess its association with patient-related and contextual risk factors. METHODS ASPIRE-ICU is a prospective, observational, multi-center cohort study nested within routine surveillance among ICU patients in Europe describing the occurrence of S. aureus and P. aeruginosa ICU pneumonia. Two thousand (2000) study cohort subjects will be enrolled (50% S. aureus colonized) in which specimens and data will be collected. Study cohort subjects will be enrolled from a larger surveillance population, in which basic surveillance data is captured. The primary outcomes are the incidence of S. aureus ICU acquired pneumonia and the incidence of P. aeruginosa ICU acquired pneumonia through ICU stay. The analysis will include advanced survival techniques (competing risks and multistate models) for each event separately as well as for the sub-distribution of ICU pneumonia to determine independent association of outcomes with risk factors.. A risk prediction model will be developed to quantify the risk for acquiring S. aureus or P. aeruginosa ICU pneumonia during ICU stay by using a composite score of independent risk factors. DISCUSSION The diagnosis of pathogen-specific ICU pneumonia is difficult, however, the criteria used in this study are objective and comparable to those in the literature. TRIAL REGISTRATION This study is registered on clinicaltrials.gov under identifier NCT02413242 .
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Affiliation(s)
- Fleur P Paling
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, HP Stratenum 6.131, PO Box 85500, 3508 GA, Utrecht, The Netherlands.
| | - Darren P R Troeman
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, HP Stratenum 6.131, PO Box 85500, 3508 GA, Utrecht, The Netherlands
| | - Martin Wolkewitz
- Institute for Medical Biometry and Statistics, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | | | - Daniël R Prins
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, HP Stratenum 6.131, PO Box 85500, 3508 GA, Utrecht, The Netherlands
| | - Susanne Weber
- Institute for Medical Biometry and Statistics, Faculty of Medicine and Medical Center, University of Freiburg, Freiburg, Germany
| | - Christine Lammens
- Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO), University of Antwerp, Wilrijk, Belgium
| | - Leen Timbermont
- Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO), University of Antwerp, Wilrijk, Belgium
| | - Herman Goossens
- Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO), University of Antwerp, Wilrijk, Belgium
| | - Surbhi Malhotra-Kumar
- Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO), University of Antwerp, Wilrijk, Belgium
| | | | - Marc J M Bonten
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, HP Stratenum 6.131, PO Box 85500, 3508 GA, Utrecht, The Netherlands.,Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Jan A J W Kluytmans
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, HP Stratenum 6.131, PO Box 85500, 3508 GA, Utrecht, The Netherlands.,Amphia Hospital, Breda, The Netherlands
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87
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Yu B, Shen Y, Qiao J, Cui Q. Geniposide attenuates Staphylococcus aureus-induced pneumonia in mice by inhibiting NF-κB activation. Microb Pathog 2017; 112:117-121. [PMID: 28958950 DOI: 10.1016/j.micpath.2017.09.050] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 09/11/2017] [Accepted: 09/24/2017] [Indexed: 02/07/2023]
Abstract
Staphylococcus aureus (S. aureus) is a major cause of pneumonia that often affects young and immunocompetent patients. Inflammation plays an important role in the development of S. aureus-induced pneumonia. Geniposide, a major iridoid glucoside component of gardenia fruit, has been reported to have anti-inflammatory and anti-oxidative effects. The purpose of this study was to investigate the protective effects of geniposide on S. aureus-induced pneumonia in mice. Lung histopathological changes were detected by hematoxylin-eosin (H&E) staining. Lung myeloperoxidase (MPO) activity, wet-to-dry (W/D) ratio, and inflammatory cytokine levels in bronchoalveolar lavage fluid (BALF) were measured. The results showed that S. aureus-induced lung histopathological changes were attenuated by geniposide. S. aureus-induced MPO activity and lung W/D ratio were inhibited by treatment of geniposide. Furthermore, the levels of TNF-α and IL-1β in the BALF were also suppressed by geniposide. In addition, geniposide significantly inhibited S. aureus-induced nuclear factor kappa B (NF-κB) activation. Taken together, these results showed that geniposide inhibited S. aureus-induced pneumonia in mice by inhibiting NF-κB signaling pathway. Geniposide might be used as a potential agent for the treatment of S. aureus-induced pneumonia.
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Affiliation(s)
- Bin Yu
- Department of Pediatrics, The First Hospital of Harbin Medical University, Harbin, China
| | - Yongbin Shen
- Department of Vascular Surgery, The Second Hospital of Harbin Medical University, Harbin, China
| | - Jiutao Qiao
- Department of Orthopedics, The Second Hospital of Harbin Medical University, Harbin, China
| | - Qingbo Cui
- Department of Pediatric Surgery, The Second Hospital of Harbin Medical University, Harbin, China.
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88
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Lacoma A, Cano V, Moranta D, Regueiro V, Domínguez-Villanueva D, Laabei M, González-Nicolau M, Ausina V, Prat C, Bengoechea JA. Investigating intracellular persistence of Staphylococcus aureus within a murine alveolar macrophage cell line. Virulence 2017; 8:1761-1775. [PMID: 28762868 PMCID: PMC5810471 DOI: 10.1080/21505594.2017.1361089] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Objective: Staphylococcus aureus is a particularly difficult pathogen to eradicate from the respiratory tract. Previous studies have highlighted the intracellular capacity of S.aureus in several phagocytic and non-phagocytic cells. The aim of this study was to define S.aureus interaction within a murine alveolar macrophage cell line. Methods: Cell line MH-S was infected with Newman strain. Molecular mechanisms involved in phagocytosis were explored. To assess whether S.aureus survives intracellularly quantitative (gentamicin protection assays and bacterial plating) and qualitative analysis (immunofluorescence microscopy) were performed. Bacterial colocalization with different markers of the endocytic pathway was examined to characterize its intracellular trafficking. Results: We found that S.aureus uptake requires host actin polymerization, microtubule assembly and activation of phosphatidylinositol 3-kinase signaling. Time course experiments showed that Newman strain was able to persist within macrophages at least until 28.5 h post infection. We observed that intracellular bacteria are located inside an acidic subcellular compartment, which co-localizes with the late endosome/lysosome markers Lamp-1, Rab7 and RILP. Colocalization counts with TMR-dextran might reflect a balance between bacterial killing and intracellular survival. Conclusions: This study indicates that S.aureus persists and replicates inside murine alveolar macrophages, representing a privileged niche that can potentially offer protection from antimicrobial activity and immunological host defense mechanisms.
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Affiliation(s)
- A Lacoma
- a Servei de Microbiologia , Hospital Universitari "Germans Trias i Pujol," Institut en Ciències de la Salut "Germans Trias i Pujol," Universitat Autònoma de Barcelona , Badalona , Spain.,b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain
| | - V Cano
- b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain.,c Laboratory "Infection and Immunity," Fundación de Investigación Sanitaria de las Islas Baleares (FISIB), Instituto de Investigación Sanitaria de Palma (IdISPa) , Palma , Spain
| | - D Moranta
- b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain.,c Laboratory "Infection and Immunity," Fundación de Investigación Sanitaria de las Islas Baleares (FISIB), Instituto de Investigación Sanitaria de Palma (IdISPa) , Palma , Spain
| | - V Regueiro
- b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain.,c Laboratory "Infection and Immunity," Fundación de Investigación Sanitaria de las Islas Baleares (FISIB), Instituto de Investigación Sanitaria de Palma (IdISPa) , Palma , Spain
| | - D Domínguez-Villanueva
- a Servei de Microbiologia , Hospital Universitari "Germans Trias i Pujol," Institut en Ciències de la Salut "Germans Trias i Pujol," Universitat Autònoma de Barcelona , Badalona , Spain
| | - M Laabei
- a Servei de Microbiologia , Hospital Universitari "Germans Trias i Pujol," Institut en Ciències de la Salut "Germans Trias i Pujol," Universitat Autònoma de Barcelona , Badalona , Spain
| | - M González-Nicolau
- b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain.,c Laboratory "Infection and Immunity," Fundación de Investigación Sanitaria de las Islas Baleares (FISIB), Instituto de Investigación Sanitaria de Palma (IdISPa) , Palma , Spain
| | - V Ausina
- a Servei de Microbiologia , Hospital Universitari "Germans Trias i Pujol," Institut en Ciències de la Salut "Germans Trias i Pujol," Universitat Autònoma de Barcelona , Badalona , Spain.,b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain
| | - C Prat
- a Servei de Microbiologia , Hospital Universitari "Germans Trias i Pujol," Institut en Ciències de la Salut "Germans Trias i Pujol," Universitat Autònoma de Barcelona , Badalona , Spain.,b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain
| | - J A Bengoechea
- b CIBER Enfermedades Respiratorias (CIBERES) , Instituto de Salud Carlos III , Madrid , Spain.,c Laboratory "Infection and Immunity," Fundación de Investigación Sanitaria de las Islas Baleares (FISIB), Instituto de Investigación Sanitaria de Palma (IdISPa) , Palma , Spain.,d Consejo Superior de Investigaciones Científicas , Madrid , Spain.,e Centre for Experimental Medicine , Queen's University Belfast , UK
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89
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Multimechanistic Monoclonal Antibodies (MAbs) Targeting Staphylococcus aureus Alpha-Toxin and Clumping Factor A: Activity and Efficacy Comparisons of a MAb Combination and an Engineered Bispecific Antibody Approach. Antimicrob Agents Chemother 2017; 61:AAC.00629-17. [PMID: 28584141 PMCID: PMC5527613 DOI: 10.1128/aac.00629-17] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 05/28/2017] [Indexed: 12/23/2022] Open
Abstract
Secreted alpha-toxin and surface-localized clumping factor A (ClfA) are key virulence determinants in Staphylococcus aureus bloodstream infections. We previously demonstrated that prophylaxis with a multimechanistic monoclonal antibody (MAb) combination against alpha-toxin (MEDI4893*) and ClfA (11H10) provided greater strain coverage and improved efficacy in an S. aureus lethal bacteremia model. Subsequently, 11H10 was found to exhibit reduced affinity and impaired inhibition of fibrinogen binding to ClfA002 expressed by members of a predominant hospital-associated methicillin-resistant S. aureus (MRSA) clone, ST5. Consequently, we identified another anti-ClfA MAb (SAR114) from human tonsillar B cells with >100-fold increased affinity for three prominent ClfA variants, including ClfA002, and potent inhibition of bacterial agglutination by 112 diverse clinical isolates. We next constructed bispecific Abs (BiSAbs) comprised of 11H10 or SAR114 as IgG scaffolds and grafted anti-alpha-toxin (MEDI4893*) single-chain variable fragment to the amino or carboxy terminus of the anti-ClfA heavy chains. Although the BiSAbs exhibited in vitro potencies similar to those of the parental MAbs, only 11H10-BiSAb, but not SAR114-BiSAb, showed protective activity in murine infection models comparable to the respective MAb combination. In vivo activity with SAR114-BiSAb was observed in infection models with S. aureus lacking ClfA. Our data suggest that high-affinity binding to ClfA sequesters the SAR114-BiSAb to the bacterial surface, thereby reducing both alpha-toxin neutralization and protection in vivo These results indicate that a MAb combination targeting ClfA and alpha-toxin is more promising for future development than the corresponding BiSAb.
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90
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Bassetti M, Poulakou G, Ruppe E, Bouza E, Van Hal SJ, Brink A. Antimicrobial resistance in the next 30 years, humankind, bugs and drugs: a visionary approach. Intensive Care Med 2017; 43:1464-1475. [PMID: 28733718 DOI: 10.1007/s00134-017-4878-x] [Citation(s) in RCA: 159] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 06/24/2017] [Indexed: 02/06/2023]
Abstract
PURPOSE To describe the current standards of care and major recent advances with regard to antimicrobial resistance (AMR) and to give a prospective overview for the next 30 years in this field. METHODS Review of medical literature and expert opinion were used in the development of this review. RESULTS There is undoubtedly a large clinical and public health burden associated with AMR in ICU, but it is challenging to quantify the associated excess morbidity and mortality. In the last decade, antibiotic stewardship and infection prevention and control have been unable to prevent the rapid spread of resistant Gram-negative bacteria (GNB), in particular carbapenem-resistant Pseudomonas aeruginosa (and other non-fermenting GNB), extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistant Enterobacteriaceae (CRE). The situation appears more optimistic currently for Gram-positive, where Staphylococcus aureus, and particularly methicillin-resistant S. aureus (MRSA), remains a cardinal cause of healthcare-associated infections worldwide. Recent advancements in laboratory techniques allow for a rapid identification of the infecting pathogen and antibiotic susceptibility testing. Their impact can be particularly relevant in settings with prevalence of MDR, since they may guide fine-tuning of empirically selected regimen, facilitate de-escalation of unnecessary antimicrobials, and support infection control decisions. Currently, antibiotics are the primary anti-infective solution for patients with known or suspected MDR bacteria in intensive care. Numerous incentives have been provided to encourage researchers to work on alternative strategies to reverse this trend and to provide a means to treat these pathogens. Although some promising antibiotics currently in phase 2 and 3 of development will soon be licensed and utilized in ICU, the continuous development of an alternative generation of compounds is extremely important. There are currently several promising avenues available to fight antibiotic resistance, such as faecal microbiota, and phage therapy.
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Affiliation(s)
- Matteo Bassetti
- Department of Medicine, Infectious Diseases Clinic, University of Udine and Azienda Sanitaria Universitaria Integrata, Piazzale S. Maria Della Misericordia 15, 33100, Udine, Italy.
| | - Garyphallia Poulakou
- Fourth Department of Internal Medicine, School of Medicine, Attikon University General Hospital, Athens National and Kapodistrian University, 1 Rimini St, 12462, Athens, Greece
| | - Etienne Ruppe
- Genomic Research Laboratory, Division of Infectious Diseases, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205, Geneva, Switzerland
| | - Emilio Bouza
- Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Department of Medicine, School of Medicine, Universidad Complutense de Madrid, Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES CB06/06/0058), Madrid, Spain
| | - Sebastian J Van Hal
- Department of Microbiology and Infectious Diseases, Royal Prince Alfred Hospital, Sydney, NSW, Australia
| | - Adrian Brink
- Ampath National Laboratory Services, Department of Clinical Microbiology, Milpark Hospital, Johannesburg, South Africa
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, Groote Schuur Hospital, University of Cape Town, Cape Town, South Africa
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91
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Mouse model of hematogenous implant-related Staphylococcus aureus biofilm infection reveals therapeutic targets. Proc Natl Acad Sci U S A 2017; 114:E5094-E5102. [PMID: 28607050 DOI: 10.1073/pnas.1703427114] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Infection is a major complication of implantable medical devices, which provide a scaffold for biofilm formation, thereby reducing susceptibility to antibiotics and complicating treatment. Hematogenous implant-related infections following bacteremia are particularly problematic because they can occur at any time in a previously stable implant. Herein, we developed a model of hematogenous infection in which an orthopedic titanium implant was surgically placed in the legs of mice followed 3 wk later by an i.v. exposure to Staphylococcus aureus This procedure resulted in a marked propensity for a hematogenous implant-related infection comprised of septic arthritis, osteomyelitis, and biofilm formation on the implants in the surgical legs compared with sham-operated surgical legs without implant placement and with contralateral nonoperated normal legs. Neutralizing human monoclonal antibodies against α-toxin (AT) and clumping factor A (ClfA), especially in combination, inhibited biofilm formation in vitro and the hematogenous implant-related infection in vivo. Our findings suggest that AT and ClfA are pathogenic factors that could be therapeutically targeted against Saureus hematogenous implant-related infections.
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92
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Hepburn L, Hijnen D, Sellman B, Mustelin T, Sleeman M, May R, Strickland I. The complex biology and contribution of Staphylococcus aureus
in atopic dermatitis, current and future therapies. Br J Dermatol 2017; 177:63-71. [DOI: 10.1111/bjd.15139] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2016] [Indexed: 12/22/2022]
Affiliation(s)
- L. Hepburn
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
| | - D.J. Hijnen
- University Medical Center Utrecht; Department of Dermatology; Utrecht the Netherlands
| | | | | | - M.A. Sleeman
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
| | - R.D. May
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
| | - I. Strickland
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
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93
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Kwon SJ, Kim D, Lee I, Kim J, Dordick JS. In vitro gene expression-coupled bacterial cell chip for screening species-specific antimicrobial enzymes. Biotechnol Bioeng 2017; 114:1648-1657. [PMID: 28369698 DOI: 10.1002/bit.26300] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Revised: 03/17/2017] [Accepted: 03/22/2017] [Indexed: 12/22/2022]
Abstract
Targeting infectious bacterial pathogens is important for reducing the evolution of antibiotic-resistant bacteria and preserving the endogenous human microbiome. Cell lytic enzymes including bacteriophage endolysins, bacterial autolysins, and other bacteriolysins are useful antibiotic alternatives due to their exceptional target selectivity, which may be used to lysins rapidly kill target bacteria and their high specificity permit the normal commensal microflora to be left undisturbed. Genetic information of numerous lysins is currently available, but the identification of their antimicrobial function and specificity has been limited because most lysins are often poorly expressed and exhibit low solubilities. Here, we report the development of bacterial cell chip for rapidly accessing the function of diverse genes that are suggestive of encoding lysins. This approach can be used to evaluate rapidly the species-specific antimicrobial activity of diverse lysins synthesized from in vitro transcription and translation (TNT) of plasmid DNA. In addition, new potent lysins can be assessed that are not expressed in hosts and display low solubility. As a result of evaluating the species-specific antimicrobial function of 11 (un)known lysins with an in vitro TNT-coupled bacterial cell chip, a potent recombinant lysin against Staphylococcus strains, SA1, was identified. The SA1 was highly potent against not only S. aureus, but also both lysostaphin-resistant S. simulans and S. epidermidis cells. To this end, the SA1 may be applicable to treat both methicillin-resistant S. aureus (MRSA) and lysostaphin-resistant MRSA mutants. Biotechnol. Bioeng. 2017;114: 1648-1657. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Seok-Joon Kwon
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York, 12180
| | - Domyoung Kim
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York, 12180
| | - Inseon Lee
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Jungbae Kim
- Department of Chemical and Biological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Jonathan S Dordick
- Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York, 12180
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94
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Sampedro GR, Bubeck Wardenburg J. Staphylococcus aureus in the Intensive Care Unit: Are These Golden Grapes Ripe for a New Approach? J Infect Dis 2017; 215:S64-S70. [PMID: 28003353 DOI: 10.1093/infdis/jiw581] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Staphylococcus aureus is the leading cause of infection in the setting of critical illness and injury. This pathogen causes life-threatening infection in otherwise healthy individuals and also complicates the clinical course of patients requiring intensive care as a result of their primary medical or surgical disease processes. S. aureus infection in the intensive care unit (ICU) most commonly manifests as sepsis, ventilator-associated pneumonia, and infection of surgical sites and indwelling medical devices. With the epidemic spread of methicillin-resistant S. aureus, many cases of staphylococcal infection in the ICU are now classified as drug resistant, prompting hospital-based screening for methicillin-resistant S. aureus and implementation of both isolation practices and decolonization strategies in ICU patients. The genetic adaptability of S. aureus, heterogeneity of disease presentation, clinical course, and outcome between individual S. aureus-infected ICU patients remains enigmatic, suggesting a need to define disease classification subtypes that inform disease progression and therapy. We propose that S. aureus infection in the ICU now presents a unique opportunity for individualized risk stratification coupled with the investigation of novel approaches to mitigate disease. Given our increasing knowledge of the molecular pathogenesis of S. aureus disease, we suggest that the application of molecular pathological epidemiology to S. aureus infection can usher in a new era of highly focused personalized therapy that may be particularly beneficial in the setting of critical illness and injury.
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Affiliation(s)
- Georgia R Sampedro
- Departments of 1 Microbiology and.,Pediatrics, University of Chicago, Illinois
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95
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Cohen TS, Pelletier M, Cheng L, Pennini ME, Bonnell J, Cvitkovic R, Chang CS, Xiao X, Cameroni E, Corti D, Semenova E, Warrener P, Sellman BR, Suzich J, Wang Q, Stover CK. Anti-LPS antibodies protect against Klebsiella pneumoniae by empowering neutrophil-mediated clearance without neutralizing TLR4. JCI Insight 2017; 2:92774. [PMID: 28469079 DOI: 10.1172/jci.insight.92774] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/29/2017] [Indexed: 12/22/2022] Open
Abstract
Initial promising results with immune sera guided early human mAb approaches against Gram-negative sepsis to an LPS neutralization mechanism, but these efforts failed in human clinical trials. Emergence of multidrug resistance has renewed interest in pathogen-specific mAbs. We utilized a pair of antibodies targeting Klebsiella pneumoniae LPS, one that both neutralizes LPS/TLR4 signaling and mediates opsonophagocytic killing (OPK) (54H7) and one that only promotes OPK (KPE33), to better understand the contribution of each mechanism to mAb protection in an acutely lethal pneumonia model. Passive immunization 24 hours prior to infection with KPE33 protected against lethal infection significantly better than 54H7, while delivery of either mAb 1 hour after infection resulted in similar levels of protection. These data suggest that early neutralization of LPS-induced signaling limits protection afforded by these mAbs. LPS neutralization prevented increases in the numbers of γδT cells, a major producer of the antimicrobial cytokine IL-17A, the contribution of which was confirmed using il17a-knockout mice. We conclude that targeting LPS for OPK without LPS signaling neutralization has potential to combat Gram-negative infection by engaging host immune defenses, rather than inhibiting beneficial innate immune pathways.
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Affiliation(s)
| | | | | | | | | | | | - Chew-Shun Chang
- Antibody Discovery and Protein Engineering, MedImmune, Gaithersburg, Maryland, USA
| | - Xiaodong Xiao
- Antibody Discovery and Protein Engineering, MedImmune, Gaithersburg, Maryland, USA
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96
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Stulik L, Hudcova J, Craven DE, Nagy G, Nagy E. Low Efficacy of Antibiotics Against Staphylococcus aureus Airway Colonization in Ventilated Patients. Clin Infect Dis 2017; 64:1081-1088. [PMID: 28158685 DOI: 10.1093/cid/cix055] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 02/02/2017] [Indexed: 11/14/2022] Open
Abstract
Background Airway-colonization by Staphylococcus aureus predisposes to the development of ventilator-associated tracheobronchitis (VAT) and ventilator-associated pneumonia (VAP). Despite extensive antibiotic treatment of intensive care unit patients, limited data are available on the efficacy of antibiotics on bacterial airway colonization and/or prevention of infections. Therefore, microbiologic responses to antibiotic treatment were evaluated in ventilated patients. Methods Results of semiquantitative analyses of S. aureus burden in serial endotracheal-aspirate (ETA) samples and VAT/VAP diagnosis were correlated to antibiotic treatment. Minimum inhibitory concentrations of relevant antibiotics using serially collected isolates were evaluated. Results Forty-eight mechanically ventilated patients who were S. aureus positive by ETA samples and treated with relevant antibiotics for at least 2 consecutive days were included in the study. Vancomycin failed to reduce methicillin-resistant S. aureus (MRSA) or methicillin-susceptible S. aureus (MSSA) burden in the airways. Oxacillin was ineffective for MSSA colonization in approximately 30% of the patients, and responders were typically coadministered additional antibiotics. Despite antibiotic exposure, 15 of the 39 patients (approximately 38%) colonized only by S. aureus and treated with appropriate antibiotic for at least 2 days still progressed to VAP. Importantly, no change in antibiotic susceptibility of S. aureus isolates was observed during treatment. Staphylococcus aureus colonization levels inversely correlated with the presence of normal respiratory flora. Conclusions Antibiotic treatment is ineffective in reducing S. aureus colonization in the lower airways and preventing VAT or VAP. Staphylococcus aureus is in competition for colonization with the normal respiratory flora. To improve patient outcomes, alternatives to antibiotics are urgently needed.
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Affiliation(s)
- Lukas Stulik
- Arsanis Biosciences GmbH, Vienna, Austria.,Arsanis, Inc, Waltham, MA, USA
| | - Jana Hudcova
- Department of Surgical Critical Care, Lahey Hospital and Medical Center, Burlington, MA, USA
| | - Donald E Craven
- Infectious Diseases, Lahey Hospital and Medical Center, Burlington, Massachusetts, USA
| | - Gabor Nagy
- Arsanis Biosciences GmbH, Vienna, Austria.,Arsanis, Inc, Waltham, MA, USA
| | - Eszter Nagy
- Arsanis Biosciences GmbH, Vienna, Austria.,Arsanis, Inc, Waltham, MA, USA
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97
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Targeting Alpha Toxin To Mitigate Its Lethal Toxicity in Ferret and Rabbit Models of Staphylococcus aureus Necrotizing Pneumonia. Antimicrob Agents Chemother 2017; 61:AAC.02456-16. [PMID: 28115346 DOI: 10.1128/aac.02456-16] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 01/15/2017] [Indexed: 11/20/2022] Open
Abstract
The role broad-spectrum antibiotics play in the spread of antimicrobial resistance, coupled with their effect on the healthy microbiome, has led to advances in pathogen-specific approaches for the prevention or treatment of serious bacterial infections. One approach in clinical testing is passive immunization with a monoclonal antibody (MAb) targeting alpha toxin for the prevention or treatment of Staphylococcus aureus pneumonia. Passive immunization with the human anti-alpha toxin MAb, MEDI4893*, has been shown to improve disease outcome in murine S. aureus pneumonia models. The species specificity of some S. aureus toxins necessitates testing anti-S. aureus therapeutics in alternate species. We developed a necrotizing pneumonia model in ferrets and utilized an existing rabbit pneumonia model to characterize MEDI4893* protective activity in species other than mice. MEDI4893* prophylaxis reduced disease severity in ferret and rabbit pneumonia models against both community-associated methicillin-resistant S. aureus (MRSA) and hospital-associated MRSA strains. In addition, adjunctive treatment of MEDI4893* with either vancomycin or linezolid provided enhanced protection in rabbits relative to the antibiotics alone. These results confirm that MEDI4893 is a promising candidate for immunotherapy against S. aureus pneumonia.
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98
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Babb R, Pirofski LA. Help is on the way: Monoclonal antibody therapy for multi-drug resistant bacteria. Virulence 2017; 8:1055-1058. [PMID: 28306387 PMCID: PMC5711430 DOI: 10.1080/21505594.2017.1306620] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Rachelle Babb
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, NY, USA
| | - Liise-anne Pirofski
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, NY, USA,CONTACT Liise-anne Pirofski Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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99
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Munguia J, Nizet V. Pharmacological Targeting of the Host-Pathogen Interaction: Alternatives to Classical Antibiotics to Combat Drug-Resistant Superbugs. Trends Pharmacol Sci 2017; 38:473-488. [PMID: 28283200 DOI: 10.1016/j.tips.2017.02.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Revised: 02/13/2017] [Accepted: 02/14/2017] [Indexed: 01/17/2023]
Abstract
The rise of multidrug-resistant pathogens and the dearth of new antibiotic development place an existential strain on successful infectious disease therapy. Breakthrough strategies that go beyond classical antibiotic mechanisms are needed to combat this looming public health catastrophe. Reconceptualizing antibiotic therapy in the richer context of the host-pathogen interaction is required for innovative solutions. By defining specific virulence factors, the essence of a pathogen, and pharmacologically neutralizing their activities, one can block disease progression and sensitize microbes to immune clearance. Likewise, host-directed strategies to boost phagocyte bactericidal activity, enhance leukocyte recruitment, or reverse pathogen-induced immunosuppression seek to replicate the success of cancer immunotherapy in the field of infectious diseases. The answer to the threat of multidrug-resistant pathogens lies 'outside the box' of current antibiotic paradigms.
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Affiliation(s)
- Jason Munguia
- Department of Pediatrics, Division of Host-Microbe Systems and Therapeutics, University of California San Diego, La Jolla, CA 92093, USA; Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA 92093, USA
| | - Victor Nizet
- Department of Pediatrics, Division of Host-Microbe Systems and Therapeutics, University of California San Diego, La Jolla, CA 92093, USA; Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, CA 92093, USA; Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA; Rady Children's Hospital, San Diego, CA 92123, USA.
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100
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Bagnoli F. Staphylococcus aureus toxin antibodies: Good companions of antibiotics and vaccines. Virulence 2017; 8:1037-1042. [PMID: 28267417 DOI: 10.1080/21505594.2017.1295205] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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