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Soltanmohammadi B, Piri‐Gavgani S, Basardeh E, Ghanei M, Azizi M, Khaksar Z, Sharifzadeh Z, Badmasti F, Soezi M, Fateh A, Azimi P, Siadat SD, Shooraj F, Bouzari S, Omrani MD, Rahimi‐Jamnani F. Bactericidal fully human single-chain fragment variable antibodies protect mice against methicillin-resistant Staphylococcus aureus bacteraemia. Clin Transl Immunology 2021; 10:e1302. [PMID: 34221401 PMCID: PMC8240403 DOI: 10.1002/cti2.1302] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 05/01/2021] [Accepted: 05/30/2021] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVES The increasing prevalence of antibiotic-resistant Staphylococcus aureus, besides the inadequate numbers of effective antibiotics, emphasises the need to find new therapeutic agents against this lethal pathogen. METHODS In this study, to obtain antibody fragments against S. aureus, a human single-chain fragment variable (scFv) library was enriched against living methicillin-resistant S. aureus (MRSA) cells, grown in three different conditions, that is human peripheral blood mononuclear cells with plasma, whole blood and biofilm. The antibacterial activity of scFvs was evaluated by the growth inhibition assay in vitro. Furthermore, the therapeutic efficacy of anti-S. aureus scFvs was appraised in a mouse model of bacteraemia. RESULTS Three scFv antibodies, that is MEH63, MEH158 and MEH183, with unique sequences, were found, which exhibited significant binding to S. aureus and reduced the viability of S. aureus in in vitro inhibition assays. Based on the results, MEH63, MEH158 and MEH183, in addition to their combination, could prolong the survival rate, reduce the bacterial burden in the blood and prevent inflammation and tissue destruction in the kidneys and spleen of mice with MRSA bacteraemia compared with the vehicle group (treated with normal saline). CONCLUSION The combination therapy with anti-S. aureus scFvs and conventional antibiotics might shed light on the treatment of patients with S. aureus infections.
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Affiliation(s)
- Behnoush Soltanmohammadi
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Somayeh Piri‐Gavgani
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Eilnaz Basardeh
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Mostafa Ghanei
- Chemical Injuries Research CenterSystems Biology and Poisoning InstituteBaqiyatallah University of Medical SciencesTehranIran
| | - Masoumeh Azizi
- Molecular Medicine Department, Biotechnology Research CenterPasteur Institute of IranTehranIran
| | - Zabihollah Khaksar
- Department of Basic SciencesSchool of Veterinary MedicineShiraz UniversityShirazIran
| | | | - Farzad Badmasti
- Department of BacteriologyPasteur Institute of IranTehranIran
| | - Mahdieh Soezi
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Abolfazl Fateh
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Parisa Azimi
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Seyed Davar Siadat
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Fahimeh Shooraj
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
| | - Saeid Bouzari
- Molecular Biology DepartmentPasteur Institute of IranTehranIran
| | - Mir Davood Omrani
- Department of Medical GeneticsSchool of MedicineShahid Beheshti University of Medical SciencesTehranIran
| | - Fatemeh Rahimi‐Jamnani
- Department of Mycobacteriology and Pulmonary ResearchPasteur Institute of IranTehranIran
- Microbiology Research CenterPasteur Institute of IranTehranIran
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2
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Mirzaei B, Babaei R, Valinejad S. Staphylococcal Vaccine Antigens related to biofilm formation. Hum Vaccin Immunother 2021; 17:293-303. [PMID: 32498595 PMCID: PMC7872035 DOI: 10.1080/21645515.2020.1767449] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Accepted: 05/05/2020] [Indexed: 10/24/2022] Open
Abstract
The number and frequency of multidrug-resistant (MDR) strains as a frequent cause of nosocomial infections have increased, especially for Methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis, in part due to device-related infections. The transition to antibiotic-resistance in related bacterial genes and the capability for immune escape have increased the sustainability of biofilms produced by these bacteria. The formation and changes in biofilms have been suggested as a target to prevent or treat staphylococcal infections. Thus, this study reviews the development of candidate staphylococcal vaccines by database searching, and evaluates the immunogenicity and efficacy profiles of bacterial components involved in biofilms. The literature suggests that using common staphylococcal vaccine antigens and multivalent vaccines should further enhance vaccine efficacy.
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Affiliation(s)
- Bahman Mirzaei
- Department of Medical Microbiology and Virology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
- Department of Medical Microbiology and Virology, School of Medicine, Zanjan University of Medical Science, Zanjan, Iran
| | - Ryhaneh Babaei
- Department of Medical Microbiology and Virology, School of Medicine, Zanjan University of Medical Science, Zanjan, Iran
| | - Sina Valinejad
- Department of Medical Microbiology and Virology, School of Medicine, Zanjan University of Medical Science, Zanjan, Iran
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3
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Overview of Staphylococcus epidermidis cell wall-anchored proteins: potential targets to inhibit biofilm formation. Mol Biol Rep 2019; 47:771-784. [DOI: 10.1007/s11033-019-05139-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 10/11/2019] [Indexed: 12/18/2022]
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4
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Hofmans D, Khodaparast L, Khodaparast L, Vanstreels E, Shahrooei M, Van Eldere J, Van Mellaert L. Ses proteins as possible targets for vaccine development against Staphylococcus epidermidis infections. J Infect 2018; 77:119-130. [DOI: 10.1016/j.jinf.2018.03.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 12/15/2022]
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5
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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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6
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Diep BA, Le VTM, Badiou C, Le HN, Pinheiro MG, Duong AH, Wang X, Dip EC, Aguiar-Alves F, Basuino L, Marbach H, Mai TT, Sarda MN, Kajikawa O, Matute-Bello G, Tkaczyk C, Rasigade JP, Sellman BR, Chambers HF, Lina G. IVIG-mediated protection against necrotizing pneumonia caused by MRSA. Sci Transl Med 2017; 8:357ra124. [PMID: 27655850 DOI: 10.1126/scitranslmed.aag1153] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 09/02/2016] [Indexed: 12/12/2022]
Abstract
New therapeutic approaches are urgently needed to improve survival outcomes for patients with necrotizing pneumonia caused by Staphylococcus aureus One such approach is adjunctive treatment with intravenous immunoglobulin (IVIG), but clinical practice guidelines offer conflicting recommendations. In a preclinical rabbit model, prophylaxis with IVIG conferred protection against necrotizing pneumonia caused by five different epidemic strains of community-associated methicillin-resistant S. aureus (MRSA) as well as a widespread strain of hospital-associated MRSA. Treatment with IVIG, either alone or in combination with vancomycin or linezolid, improved survival outcomes in this rabbit model. Two specific IVIG antibodies that neutralized the toxic effects of α-hemolysin (Hla) and Panton-Valentine leukocidin (PVL) conferred protection against necrotizing pneumonia in the rabbit model. This mechanism of action of IVIG was uncovered by analyzing loss-of-function mutant bacterial strains containing deletions in 17 genes encoding staphylococcal exotoxins, which revealed only Hla and PVL as having an impact on necrotizing pneumonia. These results demonstrate the potential clinical utility of IVIG in the treatment of severe pneumonia induced by S. aureus.
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Affiliation(s)
- Binh An Diep
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA.
| | - Vien T M Le
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Cedric Badiou
- INSERM U1111, Université Lyon 1, CNRS UMR5308, ENS Lyon, Lyon, France. Centre National de Référence des Staphylocoques, Hospices Civils de Lyon, Bron, France
| | - Hoan N Le
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Marcos Gabriel Pinheiro
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA. Pathology Program, Fluminense Federal University, Niterói, RJ, Brazil
| | - Au H Duong
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Xing Wang
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Etyene Castro Dip
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Fábio Aguiar-Alves
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA. Pathology Program, Fluminense Federal University, Niterói, RJ, Brazil
| | - Li Basuino
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Helene Marbach
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Thuy T Mai
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Marie N Sarda
- Laboratory of Immunology, Centre Hospitalier Lyon Sud, Hospices Civils de Lyon, Lyon, France
| | - Osamu Kajikawa
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98109, USA
| | - Gustavo Matute-Bello
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98109, USA
| | - Christine Tkaczyk
- Department of Infectious Diseases, MedImmune, LLC, Gaithersburg, MD 20878, USA
| | - Jean-Philippe Rasigade
- INSERM U1111, Université Lyon 1, CNRS UMR5308, ENS Lyon, Lyon, France. Centre National de Référence des Staphylocoques, Hospices Civils de Lyon, Bron, France
| | - Bret R Sellman
- Department of Infectious Diseases, MedImmune, LLC, Gaithersburg, MD 20878, USA
| | - Henry F Chambers
- Division of HIV, Infectious Diseases, and Global Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA 94110, USA
| | - Gerard Lina
- INSERM U1111, Université Lyon 1, CNRS UMR5308, ENS Lyon, Lyon, France. Centre National de Référence des Staphylocoques, Hospices Civils de Lyon, Bron, France.
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Sabaté Brescó M, Harris LG, Thompson K, Stanic B, Morgenstern M, O'Mahony L, Richards RG, Moriarty TF. Pathogenic Mechanisms and Host Interactions in Staphylococcus epidermidis Device-Related Infection. Front Microbiol 2017; 8:1401. [PMID: 28824556 PMCID: PMC5539136 DOI: 10.3389/fmicb.2017.01401] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 07/11/2017] [Indexed: 12/25/2022] Open
Abstract
Staphylococcus epidermidis is a permanent member of the normal human microbiota, commonly found on skin and mucous membranes. By adhering to tissue surface moieties of the host via specific adhesins, S. epidermidis is capable of establishing a lifelong commensal relationship with humans that begins early in life. In its role as a commensal organism, S. epidermidis is thought to provide benefits to human host, including out-competing more virulent pathogens. However, largely due to its capacity to form biofilm on implanted foreign bodies, S. epidermidis has emerged as an important opportunistic pathogen in patients receiving medical devices. S. epidermidis causes approximately 20% of all orthopedic device-related infections (ODRIs), increasing up to 50% in late-developing infections. Despite this prevalence, it remains underrepresented in the scientific literature, in particular lagging behind the study of the S. aureus. This review aims to provide an overview of the interactions of S. epidermidis with the human host, both as a commensal and as a pathogen. The mechanisms retained by S. epidermidis that enable colonization of human skin as well as invasive infection, will be described, with a particular focus upon biofilm formation. The host immune responses to these infections are also described, including how S. epidermidis seems to trigger low levels of pro-inflammatory cytokines and high levels of interleukin-10, which may contribute to the sub-acute and persistent nature often associated with these infections. The adaptive immune response to S. epidermidis remains poorly described, and represents an area which may provide significant new discoveries in the coming years.
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Affiliation(s)
- Marina Sabaté Brescó
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland.,Molecular Immunology, Swiss Institute of Allergy and Asthma Research, University of ZurichDavos, Switzerland
| | - Llinos G Harris
- Microbiology and Infectious Diseases, Institute of Life Science, Swansea University Medical SchoolSwansea, United Kingdom
| | - Keith Thompson
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
| | - Barbara Stanic
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
| | - Mario Morgenstern
- Department of Orthopedic and Trauma Surgery, University Hospital BaselBasel, Switzerland
| | - Liam O'Mahony
- Molecular Immunology, Swiss Institute of Allergy and Asthma Research, University of ZurichDavos, Switzerland
| | - R Geoff Richards
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
| | - T Fintan Moriarty
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
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8
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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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9
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Targeting Alpha Toxin and ClfA with a Multimechanistic Monoclonal-Antibody-Based Approach for Prophylaxis of Serious Staphylococcus aureus Disease. mBio 2016; 7:mBio.00528-16. [PMID: 27353753 PMCID: PMC4937210 DOI: 10.1128/mbio.00528-16] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Staphylococcus aureus produces numerous virulence factors, each contributing different mechanisms to bacterial pathogenesis in a spectrum of diseases. Alpha toxin (AT), a cytolytic pore-forming toxin, plays a key role in skin and soft tissue infections and pneumonia, and a human anti-AT monoclonal antibody (MAb), MEDI4893*, has been shown to reduce disease severity in dermonecrosis and pneumonia infection models. However, interstrain diversity and the complex pathogenesis of S. aureus bloodstream infections suggests that MEDI4893* alone may not provide adequate protection against S. aureus sepsis. Clumping factor A (ClfA), a fibrinogen binding protein, is an important virulence factor facilitating S. aureus bloodstream infections. Herein, we report on the identification of a high-affinity anti-ClfA MAb, 11H10, that inhibits ClfA binding to fibrinogen, prevents bacterial agglutination in human plasma, and promotes opsonophagocytic bacterial killing (OPK). 11H10 prophylaxis reduced disease severity in a mouse bacteremia model and was dependent on Fc effector function and OPK. Additionally, prophylaxis with 11H10 in combination with MEDI4893* provided enhanced strain coverage in this model and increased survival compared to that obtained with the individual MAbs. The MAb combination also reduced disease severity in murine dermonecrosis and pneumonia models, with activity similar to that of MEDI4893* alone. These results indicate that an MAb combination targeting multiple virulence factors provides benefit over a single MAb neutralizing one virulence mechanism by providing improved efficacy, broader strain coverage, and protection against multiple infection pathologies. Alternative strategies to broad-spectrum antibiotics are required to combat the antibiotic resistance epidemic. Previous attempts at active or passive immunization against Staphylococcus aureus targeting single antigens have failed in clinical trials despite positive preclinical data. To provide broad disease and isolate coverage, an effective immunization strategy likely must target multiple virulence mechanisms of the pathogen. Herein, we tested a multimechanistic MAb combination targeting alpha toxin (AT) and clumping factor A (ClfA) that neutralizes AT-mediated cytotoxicity, blocks fibrinogen binding by ClfA, prevents bacterial agglutination, targets the bacteria for opsonophagocytic killing, and provides broad isolate coverage in a lethal-bacteremia model. Although each MAb alone was effective in bacteremia against some individual isolates, the MAb combination provided improved protection against other isolates. These results illustrate the importance of targeting multiple virulence mechanisms and highlight the potential for an MAb combination targeting AT and ClfA to effectively prevent S. aureus disease.
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10
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Sause WE, Buckley PT, Strohl WR, Lynch AS, Torres VJ. Antibody-Based Biologics and Their Promise to Combat Staphylococcus aureus Infections. Trends Pharmacol Sci 2015; 37:231-241. [PMID: 26719219 DOI: 10.1016/j.tips.2015.11.008] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/18/2015] [Accepted: 11/19/2015] [Indexed: 11/26/2022]
Abstract
The growing incidence of serious infections mediated by methicillin-resistant Staphylococcus aureus (MRSA) strains poses a significant risk to public health. This risk is exacerbated by a prolonged void in the discovery and development of truly novel antibiotics and the absence of a vaccine. These gaps have created renewed interest in the use of biologics in the prevention and treatment of serious staphylococcal infections. In this review, we focus on efforts towards the discovery and development of antibody-based biologic agents and their potential as clinical agents in the management of serious S. aureus infections. Recent promising data for monoclonal antibodies (mAbs) targeting anthrax and Ebola highlight the potential of antibody-based biologics as therapeutic agents for serious infections.
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Affiliation(s)
- William E Sause
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
| | - Peter T Buckley
- Janssen Research & Development LLC, 1400 McKean Road, Spring House, PA 19477, USA
| | - William R Strohl
- Janssen Research & Development LLC, 1400 McKean Road, Spring House, PA 19477, USA
| | - A Simon Lynch
- Janssen Research & Development LLC, 1400 McKean Road, Spring House, PA 19477, USA.
| | - Victor J Torres
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA.
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Choi SJ, Kim MH, Jeon J, Kim OY, Choi Y, Seo J, Hong SW, Lee WH, Jeon SG, Gho YS, Jee YK, Kim YK. Active Immunization with Extracellular Vesicles Derived from Staphylococcus aureus Effectively Protects against Staphylococcal Lung Infections, Mainly via Th1 Cell-Mediated Immunity. PLoS One 2015; 10:e0136021. [PMID: 26333035 PMCID: PMC4558092 DOI: 10.1371/journal.pone.0136021] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 07/30/2015] [Indexed: 01/26/2023] Open
Abstract
Staphylococcus aureus is an important pathogenic bacterium that causes various infectious diseases. Extracellular vesicles (EVs) released from S. aureus contain bacterial proteins, nucleic acids, and lipids. These EVs can induce immune responses leading to similar symptoms as during staphylococcal infection condition and have the potential as vaccination agent. Here, we show that active immunization (vaccination) with S. aureus-derived EVs induce adaptive immunity of antibody and T cell responses. In addition, these EVs have the vaccine adjuvant ability to induce protective immunity such as the up-regulation of co-stimulatory molecules and the expression of T cell polarizing cytokines in antigen-presenting cells. Moreover, vaccination with S. aureus EVs conferred protection against lethality induced by airway challenge with lethal dose of S. aureus and also pneumonia induced by the administration of sub-lethal dose of S. aureus. These protective effects were also found in mice that were adoptively transferred with splenic T cells isolated from S. aureus EV-immunized mice, but not in serum transferred mice. Furthermore, this protective effect of S. aureus EVs was significantly reduced by the absence of interferon-gamma, but not by the absence of interleukin-17. Together, the study herein suggests that S. aureus EVs are a novel vaccine candidate against S. aureus infections, mainly via Th1 cellular response.
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Affiliation(s)
- Seng Jin Choi
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Min-Hye Kim
- Department of Medicine, Ewha Womans University School of Medicine and Ewha Institute of Convergence Medicine, Ewha Womans Medical Center, Seoul, Republic of Korea
| | - Jinseong Jeon
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Oh Youn Kim
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Youngwoo Choi
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Jihye Seo
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Sung-Wook Hong
- Academy of Immunology and Microbiology (AIM), Institute for Basic Science (IBS), Pohang, Republic of Korea
- Department of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Won-Hee Lee
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Seong Gyu Jeon
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
- * E-mail: (YK); (SJ)
| | - Yong Song Gho
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Young-Koo Jee
- Department of Internal Medicine, Dankook University College of Medicine, Cheonan, Republic of Korea
| | - Yoon-Keun Kim
- Department of Medicine, Ewha Womans University School of Medicine and Ewha Institute of Convergence Medicine, Ewha Womans Medical Center, Seoul, Republic of Korea
- * E-mail: (YK); (SJ)
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12
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Scully IL, Timofeyeva Y, Keeney D, Matsuka YV, Severina E, McNeil LK, Nanra J, Hu G, Liberator PA, Jansen KU, Anderson AS. Demonstration of the preclinical correlate of protection for Staphylococcus aureus clumping factor A in a murine model of infection. Vaccine 2015; 33:5452-5457. [PMID: 26319743 DOI: 10.1016/j.vaccine.2015.08.029] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 06/04/2015] [Accepted: 08/11/2015] [Indexed: 10/23/2022]
Abstract
The Staphylococcus aureus virulence factor clumping factor A (ClfA) is a component of an investigational S. aureus prophylactic vaccine. ClfA enables S. aureus to bind to fibrinogen and platelets during the initial stages of invasive disease. Here we demonstrate that ectopic expression of ClfA is sufficient to render nonpathogenic Lactococcus lactis lethal in a murine model of systemic infection. In contrast, L. lactis expressing ClfAY338A, which cannot bind fibrinogen, did not cause death in the mice. Pathogenicity was also prevented by immunization with ClfA. This model was then used to define a preclinical correlate of protection by measuring functional antibody in a S. aureus fibrinogen binding inhibition assay (FBI) and correlating that titer with protective outcomes. Although many humans have pre-existing antibodies that bind to ClfA, only sera with a threshold functional titer in the FBI were protective in this preclinical model. This confirms that fibrinogen binding is critical for ClfA-mediated pathogenesis and demonstrates that functional antibodies against ClfA are sufficient to protect against ClfA-mediated pathogenesis in vivo, enabling the definition of a preclinical correlate of protection for ClfA-containing vaccines based on FBI titer.
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Affiliation(s)
- Ingrid L Scully
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
| | | | - David Keeney
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
| | - Yury V Matsuka
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
| | - Elena Severina
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
| | - Lisa K McNeil
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
| | - Jasdeep Nanra
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
| | - George Hu
- Pfizer Drug Safety Research & Development, Pearl River, NY 10965, USA
| | - Paul A Liberator
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
| | - Kathrin U Jansen
- Pfizer Vaccine Research and Development, Pearl River, NY 10965, USA
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Generation of a Novel Staphylococcus aureus Ghost Vaccine and Examination of Its Immunogenicity against Virulent Challenge in Rats. Infect Immun 2015; 83:2957-65. [PMID: 25964469 DOI: 10.1128/iai.00009-15] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 05/02/2015] [Indexed: 01/05/2023] Open
Abstract
Staphylococcus aureus is a Gram-positive pathogen that causes a wide range of infections in humans and animals. Bacterial ghosts are nonliving, empty cell envelopes and are well represented as novel vaccine candidates. In this study, we examined the immunogenicity and protective efficacy of S. aureus ghosts (SAGs) against a virulent challenge in rats. Nonliving SAGs were generated by using the MIC of sodium hydroxide. The formation of a transmembrane lysis tunnel structure in SAGs was visualized by scanning electron microscopy. To investigate these SAGs as a vaccine candidate, rats were divided into four groups, A (nonimmunized control), B (orally immunized), C (subcutaneously immunized), and D (intravenously immunized). The IgG antibody responses were significantly stronger in the SAG-immunized groups than in the nonimmunized control group (P < 0.05). Moreover, a significant increase in the populations of CD4(+) and CD8(+) T cells was observed in all three immunized groups (P < 0.05). We also found that serum bactericidal antibodies were significantly elicited in the SAG-immunized groups (P < 0.05). Most importantly, the bacterial loads in the immunized groups were significantly lower than those in the nonimmunized control group (P < 0.01). These results suggest that immunization with SAGs induces immune responses and provides protection against a virulent S. aureus challenge.
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Abstract
Prosthetic joint infection (PJI) still remains a significant problem. In line with the forecasted rise in joint replacement procedures, the number of cases of PJI is also anticipated to rise. The formation of biofilm by causative pathogens is central to the occurrence and the recalcitrance of PJI. The subject of microbial biofilms is receiving increasing attention, probably as a result of the wide acknowledgement of the ubiquity of biofilms in the natural, industrial, and clinical contexts, as well as the notorious difficulty in eradicating them. In this review, we discuss the pertinent issues surrounding PJI and the challenges posed by biofilms regarding diagnosis and treatment. In addition, we discuss novel strategies of prevention and treatment of biofilm-related PJI.
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Affiliation(s)
| | | | - Jason C Webb
- Avon Orthopedic Centre, Southmead Hospital,University of Bristol
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15
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Van Mellaert L, Shahrooei M, Hofmans D, Eldere JV. Immunoprophylaxis and immunotherapy ofStaphylococcus epidermidisinfections: challenges and prospects. Expert Rev Vaccines 2014; 11:319-34. [DOI: 10.1586/erv.11.190] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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16
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Use of a human-like low-grade bacteremia model of experimental endocarditis to study the role of Staphylococcus aureus adhesins and platelet aggregation in early endocarditis. Infect Immun 2012; 81:697-703. [PMID: 23250949 DOI: 10.1128/iai.01030-12] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Animal models of infective endocarditis (IE) induced by high-grade bacteremia revealed the pathogenic roles of Staphylococcus aureus surface adhesins and platelet aggregation in the infection process. In humans, however, S. aureus IE possibly occurs through repeated bouts of low-grade bacteremia from a colonized site or intravenous device. Here we used a rat model of IE induced by continuous low-grade bacteremia to explore further the contributions of S. aureus virulence factors to the initiation of IE. Rats with aortic vegetations were inoculated by continuous intravenous infusion (0.0017 ml/min over 10 h) with 10(6) CFU of Lactococcus lactis pIL253 or a recombinant L. lactis strain expressing an individual S. aureus surface protein (ClfA, FnbpA, BCD, or SdrE) conferring a particular adhesive or platelet aggregation property. Vegetation infection was assessed 24 h later. Plasma was collected at 0, 2, and 6 h postinoculation to quantify the expression of tumor necrosis factor (TNF), interleukin 1α (IL-1α), IL-1β, IL-6, and IL-10. The percentage of vegetation infection relative to that with strain pIL253 (11%) increased when binding to fibrinogen was conferred on L. lactis (ClfA strain) (52%; P = 0.007) and increased further with adhesion to fibronectin (FnbpA strain) (75%; P < 0.001). Expression of fibronectin binding alone was not sufficient to induce IE (BCD strain) (10% of infection). Platelet aggregation increased the risk of vegetation infection (SdrE strain) (30%). Conferring adhesion to fibrinogen and fibronectin favored IL-1β and IL-6 production. Our results, with a model of IE induced by low-grade bacteremia, resembling human disease, extend the essential role of fibrinogen binding in the initiation of S. aureus IE. Triggering of platelet aggregation or an inflammatory response may contribute to or promote the development of IE.
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Maira-Litrán T, Bentancor LV, Bozkurt-Guzel C, O'Malley JM, Cywes-Bentley C, Pier GB. Synthesis and evaluation of a conjugate vaccine composed of Staphylococcus aureus poly-N-acetyl-glucosamine and clumping factor A. PLoS One 2012; 7:e43813. [PMID: 22970144 PMCID: PMC3435376 DOI: 10.1371/journal.pone.0043813] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Accepted: 07/26/2012] [Indexed: 11/18/2022] Open
Abstract
The increasing frequency, severity and antimicrobial resistance of Staphylococcus aureus infections has made the development of immunotherapies against this pathogen more urgent than ever. Previous immunization attempts using monovalent antigens resulted in at best partial levels of protection against S. aureus infection. We therefore reasoned that synthesizing a bivalent conjugate vaccine composed of two widely expressed antigens of S. aureus would result in additive/synergetic activities by antibodies to each vaccine component and/or in increased strain coverage. For this we used reductive amination, to covalently link the S. aureus antigens clumping factor A (ClfA) and deacetylated poly-N-β-(1-6)-acetyl-glucosamine (dPNAG). Mice immunized with 1, 5 or 10 µg of the dPNAG-ClfA conjugate responded in a dose-dependent manner with IgG to dPNAG and ClfA, whereas mice immunized with a mixture of ClfA and dPNAG developed significantly lower antibody titers to ClfA and no antibodies to PNAG. The dPNAG-ClfA vaccine was also highly immunogenic in rabbits, rhesus monkeys and a goat. Moreover, affinity-purified, antibodies to ClfA from dPNAG-ClfA immune serum blocked the binding of three S. aureus strains to immobilized fibrinogen. In an opsonophagocytic assay (OPKA) goat antibodies to dPNAG-ClfA vaccine, in the presence of complement and polymorphonuclear cells, killed S. aureus Newman and, to a lower extent, S. aureus Newman ΔclfA. A PNAG-negative isogenic mutant was not killed. Moreover, PNAG antigen fully inhibited the killing of S. aureus Newman by antisera to dPNAG-ClfA vaccine. Finally, mice passively vaccinated with goat antisera to dPNAG-ClfA or dPNAG-diphtheria toxoid conjugate had comparable levels of reductions of bacteria in the blood 2 h after infection with three different S. aureus strains as compared to mice given normal goat serum. In conclusion, ClfA is an immunogenic carrier protein that elicited anti-adhesive antibodies that fail to augment the OPK and protective activities of antibodies to the PNAG cell surface polysaccharide.
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Affiliation(s)
- Tomás Maira-Litrán
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America.
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Hofmann CM, Anderson JM, Marchant RE. Targeted delivery of vancomycin to Staphylococcus epidermidis biofilms using a fibrinogen-derived peptide. J Biomed Mater Res A 2012; 100:2517-25. [PMID: 22623343 PMCID: PMC3461832 DOI: 10.1002/jbm.a.34166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Accepted: 02/06/2012] [Indexed: 11/08/2022]
Abstract
This study reports on the use of a fibrinogen-derived peptide for the specific targeting and delivery of vancomycin to Staphylococcus epidermidis biofilms. One method by which S. epidermidis initially adheres to biomaterials uses the plasma protein fibrinogen as an intermediary, where the S. epidermidis surface protein SdrG binds to a short amino acid sequence near the amino terminus of the Bβ chain of fibrinogen. We mimicked this binding interaction and demonstrated the use of a synthetic fibrinogen-based β6-20 peptide to target and deliver vancomycin to S. epidermidis in vitro. The β6-20 peptide was synthesized and labeled with a Nanogold probe, and its targeting capabilities were examined through the use of scanning electron microscopy. The Nanogold component was then replaced by vancomycin, utilizing a flexible, variable length poly(ethylene glycol) linker between the peptide and antibiotic to create the targeted vancomycin products, β6-20-PEG(x) -VAN. Initial binding to surface adherent S. epidermidis was increased in a concentration-dependent manner relative to vancomycin for all equivalent concentrations ≥4 μg/mL, with targeted vancomycin content up to 22.9 times that of vancomycin alone. Retention of the targeted antibiotics was measured after an additional 24-h incubation period, revealing levels 1.3 times that of vancomycin. The results demonstrate the improved targeting and retention of vancomycin within a biofilm due to the incorporation of a specific targeting motif.
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Affiliation(s)
- Christopher M Hofmann
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
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19
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Antiphagocytic function of an IgG glycosyl hydrolase from Streptococcus equi subsp. equi and its use as a vaccine component. Infect Immun 2012; 80:2914-9. [PMID: 22615244 DOI: 10.1128/iai.06083-11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
EndoSe from Streptococcus equi subsp. equi is an enzyme hydrolyzing glycosyl groups on IgG, analogous to EndoS from Streptococcus pyogenes. We here show that the activity of EndoSe leads to an antiphagocytic function and may thus be a contributory factor to immune evasion of S. equi. Despite the damaging effect that EndoSe has on IgG, antibodies against EndoSe can neutralize its function. Antibodies against EndoSe restored the opsonic activity of specific opsonizing antibodies. Mice infected with either S. equi subsp. equi or subsp. zooepidemicus or S. pyogenes could be protected by vaccination with EndoSe. It is speculated that EndoSe could be a suitable vaccine candidate against streptococcal infections.
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Shahani L, Singh S, Khardori NM. Immunotherapy in clinical medicine: historical perspective and current status. Med Clin North Am 2012; 96:421-31, ix. [PMID: 22703849 DOI: 10.1016/j.mcna.2012.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In humans, the immune system is a complex organ system involving cells and soluble mediators whose function is, essentially, protection. However, disequilibrium in this intricate system leads to disease in itself. To modulate these responses, immunotherapy is now the primary or adjunct treatment of many diseases. In addition, immunologic tests now diagnose several diseases.
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Affiliation(s)
- Lokesh Shahani
- Department of Medicine, Southern Illinois University School of Medicine, 801 North Rutledge, PO Box 9636, Springfield, IL 62794, USA
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21
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Pancari G, Fan H, Smith S, Joshi A, Haimbach R, Clark D, Li Y, Hua J, McKelvey T, Ou Y, Drummond J, Cope L, Montgomery D, McNeely T. Characterization of the mechanism of protection mediated by CS-D7, a monoclonal antibody to Staphylococcus aureus iron regulated surface determinant B (IsdB). Front Cell Infect Microbiol 2012; 2:36. [PMID: 22919628 PMCID: PMC3417506 DOI: 10.3389/fcimb.2012.00036] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 03/03/2012] [Indexed: 11/13/2022] Open
Abstract
We previously reported the development of a human monoclonal antibody (CS-D7, IgG1) with specificity and affinity for the iron regulated surface determinant B (IsdB) of Staphylococcus aureus. CS-D7 mediates opsonophagocytic killing in vitro and protection in a murine sepsis model. In light of recent data indicating that IsdB specific T cells (CD4+, Th17), not Ab, mediate protection after vaccination with IsdB, it is important to investigate the mechanism of protection mediated by CS-D7. The mAb was examined to determine if it blocked heme binding to IsdB in vitro. The mAb was not found to have heme blocking activity, nor did it prevent bacterial growth under in vivo conditions, in an implanted growth chamber. To assess the role of the mAb Fc a point mutation was introduced at aa 297 (CS-D7·N297A). This point mutation removes Fc effector functions. In vitro analysis of the mutein confirmed that it lacked measurable binding to FcγR, and that it did not fix complement. The mutein had dramatically reduced in vitro opsonic OP activity compared to CS-D7. Nonetheless, the mutein conferred protection equivalent to the wild type mAb in the murine sepsis model. Both wild type and mutein mAbs were efficacious in FcγR deletion mice (including both FcγRII−/− mice and FcγRIII−/− mice), indicating that these receptors were not essential for mAb mediated protection in vivo. Protection mediated by CS-D7 was lost in Balb/c mice depleted of C3 with cobra venom factor (CFV), was lost in mice depleted of superoxide dismutase (SOD) in P47phox deletion mice, and as previously reported, was absent in SCID mice (Joshi et al., 2012). Enhanced clearance of S. aureus in the liver of CS-D7 treated mice and enhanced production of IFN-γ, but not of IL17, may play a role in the mechanism of protection mediated by the mAb. CS-D7 apparently mediates survival in challenged mice through a mechanism involving complement, phagocytes, and lymphocytes, but which does not depend on interaction with FcγR, or on blocking heme uptake.
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Affiliation(s)
- Gregory Pancari
- Department of Vaccine Basic Research, Merck Research Labs, Merck/MSD, West Point PA, USA
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Joshi A, Pancari G, Cope L, Bowman EP, Cua D, Proctor RA, McNeely T. Immunization with Staphylococcus aureus iron regulated surface determinant B (IsdB) confers protection via Th17/IL17 pathway in a murine sepsis model. Hum Vaccin Immunother 2012; 8:336-46. [PMID: 22327491 PMCID: PMC3426080 DOI: 10.4161/hv.18946] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have previously shown that IsdB, a conserved protein expressed by Staphylococcus aureus, induces a robust antibody response which correlates with protection in a murine challenge model. Here we investigate the role of cellular immunity in IsdB mediated protection using lymphocyte deficient SCID mice. As opposed to WT CB-17 mice the CB-17 SCID mice were not protected against a lethal challenge of S. aureus after active and passive immunizations with IsdB. Adoptive transfer of in vitro isolated lymphocyte subsets revealed that reconstituting mice with IsdB specific CD3+ or CD4+ T-cells conferred antigen specific protection while CD8+ T-cells, CD19+ B-cells and plasma cells (CD138highB220intCD19lo) alone were not protective. A combination of CD3+ T-cells plus CD19+ B-cells conferred protection in CB-17 SCID mice, whereas bovine serum albumin (BSA) immune lymphocytes did not confer protection. Active immunization experiments indicated that IsdB immunized Jh mice (B-cell deficient) were protected against lethal challenge, while nude (T-cell deficient) mice were not. In vitro assays indicated that isolated IsdB specific splenocytes from immunized mice produced abundant IL-17A, much less IFN-γ and no detectable IL-4. IL-23 deficient mice were not protected from a lethal challenge by IsdB vaccination, pointing to a critical role for CD4+ Th17 in IsdB-mediated vaccination. Neutralizing IL-17A, but not IL-22 in vivo significantly increased mortality in IsdB immunized mice; whereas, neutralizing IFN-γ did not alter IsdB-mediated protection. These findings suggest that IL-17A producing Th17 cells play an essential role in IsdB vaccine-mediated defense against invasive S. aureus infection in mice.
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Affiliation(s)
- Amita Joshi
- Merck Research Labs, Merck and Co. Inc., West Point, PA, USA.
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23
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Targeting the host–pathogen interface for treatment of Staphylococcus aureus infection. Semin Immunopathol 2011; 34:299-315. [DOI: 10.1007/s00281-011-0297-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 10/17/2011] [Indexed: 12/15/2022]
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A Novel Innate Immune-Enhancement Strategy Combined with IVIG Rescues Mice from Fatal Staphylococcus aureus Septicemia. Int J Microbiol 2011; 2011:725483. [PMID: 22164166 PMCID: PMC3227497 DOI: 10.1155/2011/725483] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 09/05/2011] [Indexed: 11/29/2022] Open
Abstract
Staphylococcus aureus (SA) is a major community-acquired pathogen. The emergence of drug-resistant strains like, methicillin-resistant SA (MRSA), poses stiff challenges to therapeutic intervention. Passive immune-therapy with specific antibodies is being actively examined to treat fulminant infections with limited success. In this study, we demonstrate that P4, a 28-amino acid peptide, derived from pneumococcal surface adhesin A along with pathogen-specific antibody (IVIG; P4 therapy) is successful in enhancing the opsonophagocytic killing (OPK) of S. aureus in vitro. We questioned if it is possible to expand P4 therapy to treat staphylococcal infections in vivo. P4 therapy in combination with IVIG rescued 7/10 morbidly ill S. aureus-infected mice while only 2/10 survived in the control group.
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Verkaik NJ, van Wamel WJB, van Belkum A. Immunotherapeutic approaches against Staphylococcus aureus. Immunotherapy 2011; 3:1063-73. [DOI: 10.2217/imt.11.84] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Staphylococcus aureus is a major cause of life-threatening infections such as bacteremia and endocarditis. Unfortunately, many strains of this bacterial species have become resistant to certain antibiotics, including methicillin and amoxicillin. These strains are known as methicillin-resistant S. aureus (MRSA). Therefore, the prophylactic and therapeutic potential of antistaphylococcal vaccines is currently being explored with priority. In animal models, (passive) immunization with (antibodies directed against) certain S. aureus surface components, staphylococcal toxins and capsular polysaccharides protects against S. aureus colonization or infection. However, immunization studies performed in humans show less promising results. So far, not a single antistaphylococcal vaccine successfully passed clinical trials. This article focuses on the results that were obtained with immunotherapeutic approaches directed against S. aureus in animal and human studies. In addition, it is discussed whether effective immunization approaches against S. aureus are feasible in humans.
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Affiliation(s)
| | - Willem JB van Wamel
- Erasmus Medical Center, Department of Medical Microbiology & Infectious Diseases, ‘s Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands
| | - Alex van Belkum
- Erasmus Medical Center, Department of Medical Microbiology & Infectious Diseases, ‘s Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands
- BioMérieux, 3 route de Port Michaud, La Balme-Les-Grottes, 38390, France
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Abstract
Infective endocarditis (IE) is lethal if not aggressively treated with antibiotics alone or in combination with surgery. The epidemiology of this condition has substantially changed over the past four decades, especially in industrialized countries. Once a disease that predominantly affected young adults with previously well-identified valve disease--mostly chronic rheumatic heart disease--IE now tends to affect older patients and new at-risk groups, including intravenous-drug users, patients with intracardiac devices, and patients exposed to healthcare-associated bacteremia. As a result, skin organisms (for example, Staphylococcus spp.) are now reported as the pathogen in these populations more often than oral streptococci, which still prevail in the community and in native-valve IE. Moreover, progress in molecular diagnostics has helped to improve the diagnosis of poorly cultivable pathogens, such as Bartonella spp. and Tropheryma whipplei, which are responsible for blood-culture-negative IE more often than expected. Epidemiological data indicate that IE mostly occurs independently of medico-surgical procedures, and that circumstantial antibiotic prophylaxis is likely to protect only a minute proportion of individuals at risk. Therefore, new strategies to prevent IE--including improvement of dental hygiene, decontamination of carriers of Staphylococcus aureus, vaccination, and, possibly, antiplatelet therapy--must be explored.
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Functional antibodies targeting IsaA of Staphylococcus aureus augment host immune response and open new perspectives for antibacterial therapy. Antimicrob Agents Chemother 2010; 55:165-73. [PMID: 20956605 DOI: 10.1128/aac.01144-10] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Staphylococcus aureus is the most common cause of nosocomial infections. Multiple antibiotic resistance and severe clinical outcomes provide a strong rationale for development of immunoglobulin-based strategies. Traditionally, novel immunological approaches against bacterial pathogens involve antibodies directed against cell surface-exposed virulence-associated epitopes or toxins. In this study, we generated a monoclonal antibody targeting the housekeeping protein IsaA, a suggested soluble lytic transglycosylase of S. aureus, and tested its therapeutic efficacy in two experimental mouse infection models. A murine anti-IsaA antibody of the IgG1 subclass (UK-66P) showed the highest binding affinity in Biacore analysis. This antibody recognized all S. aureus strains tested, including hospital-acquired and community-acquired methicillin-resistant S. aureus strains. Therapeutic efficacy in vivo in mice was analyzed using a central venous catheter-related infection model and a sepsis survival model. In both models, anti-IsaA IgG1 conferred protection against staphylococcal infection. Ex vivo, UK-66P activates professional phagocytes and induces highly microbicidal reactive oxygen metabolites in a dose-dependent manner, resulting in bacterial killing. The study provides proof of concept that monoclonal IgG1 antibodies with high affinity to the ubiquitously expressed, single-epitope-targeting IsaA are effective in the treatment of staphylococcal infection in different mouse models. Anti-IsaA antibodies might be a useful component in an antibody-based therapeutic for prophylaxis or adjunctive treatment of human cases of S. aureus infections.
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Larkin EA, Stiles BG, Ulrich RG. Inhibition of toxic shock by human monoclonal antibodies against staphylococcal enterotoxin B. PLoS One 2010; 5:e13253. [PMID: 20949003 PMCID: PMC2952590 DOI: 10.1371/journal.pone.0013253] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 09/13/2010] [Indexed: 01/16/2023] Open
Abstract
Background Staphylococcus aureus is implicated in many opportunistic bacterial infections around the world. Rising antibiotic resistance and few alternative methods of treatment are just two looming problems associated with clinical management of S. aureus. Among numerous virulence factors produced by S. aureus, staphylococcal enterotoxin (SE) B is a secreted protein that binds T-cell receptor and major histocompatibility complex class II, potentially causing toxic shock mediated by pathological activation of T cells. Recombinant monoclonal antibodies that target SEB and block receptor interactions can be of therapeutic value. Methodology/Principal Findings The inhibitory and biophysical properties of ten human monoclonal antibodies, isolated from a recombinant library by panning against SEB vaccine (STEBVax), were examined as bivalent Fabs and native full-length IgG (Mab). The best performing Fabs had binding affinities equal to polyclonal IgG, low nanomolar IC50s against SEB in cell culture assays, and protected mice from SEB-induced toxic shock. The orthologous staphylococcal proteins, SEC1 and SEC2, as well as streptococcal pyrogenic exotoxin C were recognized by several Fabs. Four Fabs against SEB, with the lowest IC50s, were converted into native full-length Mabs. Although SEB-binding kinetics were identical between each Fab and respective Mab, a 250-fold greater inhibition of SEB-induced T-cell activation was observed with two Mabs. Conclusions/Significance Results suggest that these human monoclonal antibodies possess high affinity, target specificity, and toxin neutralization qualities essential for any therapeutic agent.
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Affiliation(s)
- Eileen A. Larkin
- Immunology Department, Medical Research Institute of Infectious Diseases, Frederick, Maryland, United States of America
- Biomedical Sciences Department, Hood College, Frederick, Maryland, United States of America
| | - Bradley G. Stiles
- Immunology Department, Medical Research Institute of Infectious Diseases, Frederick, Maryland, United States of America
- Biology Department, Wilson College, Chambersburg, Pennsylvania, United States of America
- * E-mail: (BGS); (RGU)
| | - Robert G. Ulrich
- Immunology Department, Medical Research Institute of Infectious Diseases, Frederick, Maryland, United States of America
- Biomedical Sciences Department, Hood College, Frederick, Maryland, United States of America
- * E-mail: (BGS); (RGU)
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29
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Abstract
IMPORTANCE OF THE FIELD Staphylococcus aureus is a leading human pathogen in the hospital and the community. Many S. aureus strains are resistant to antibiotics, making treatment of S. aureus infections often very complicated. In contrast to many other bacterial pathogens, a working vaccine has never been found for S. aureus despite considerable efforts in academia and pharmaceutical companies. AREAS COVERED IN THIS REVIEW The latest strategies aimed at finding a working vaccine against S. aureus, including active and passive immunization efforts in pre-clinical and clinical stages, and the molecular reasons for why it may be difficult to develop a vaccine are discussed. WHAT THE READER WILL GAIN In addition to receiving an overview of current efforts in S. aureus vaccine research, the reader will understand that vaccine development for S. aureus may be difficult owing to the facts that S. aureus is a commensal microorganism and produces toxins that lyse white blood cells, thereby undermining a vaccine's role as a facilitator of opsonophagocytosis. TAKE HOME MESSAGE As a result of failed clinical trials with monovalent traditional vaccines, recent developments include a shift towards the potential use of polyvalent formulas and therapeutic antibodies and more systematic selection of optimal antigens.
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Affiliation(s)
- Michael Otto
- National Institute of Allergy and Infectious Diseases, The National Institutes of Health, Laboratory of Human Bacterial Pathogenesis, 9000 Rockville Pike, Bethesda, MD 20892, USA.
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The antigenome: from protein subunit vaccines to antibody treatments of bacterial infections? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 655:90-117. [PMID: 20047038 PMCID: PMC7123057 DOI: 10.1007/978-1-4419-1132-2_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
New strategies are needed to master infectious diseases. The so-called "passive vaccination", i.e., prevention and treatment with specific antibodies, has a proven record and potential in the management of infections and entered the medical arena more than 100 years ago. Progress in the identification of specific antigens has become the hallmark in the development of novel subunit vaccines that often contain only a single immunogen, frequently proteins, derived from the microbe in order to induce protective immunity. On the other hand, the monoclonal antibody technology has enabled biotechnology to produce antibody species in unlimited quantities and at reasonable costs that are more or less identical to their human counterparts and bind with high affinity to only one specific site of a given antigen. Although, this technology has provided a robust platform for launching novel and successful treatments against a variety of devastating diseases, it is up till now only exceptionally employed in therapy of infectious diseases. Monoclonal antibodies engaged in the treatment of specific cancers seem to work by a dual mode; they mark the cancerous cells for decontamination by the immune system, but also block a function that intervenes with cell growth. The availability of the entire genome sequence of pathogens has strongly facilitated the identification of highly specific protein antigens that are suitable targets for neutralizing antibodies, but also often seem to play an important role in the microbe's life cycle. Thus, the growing repertoire of well-characterized protein antigens will open the perspective to develop monoclonal antibodies against bacterial infections, at least as last resort treatment, when vaccination and antibiotics are no options for prevention or therapy. In the following chapter we describe and compare various technologies regarding the identification of suitable target antigens and the foundation of cognate monoclonal antibodies and discuss their possible applications in the treatment of bacterial infections together with an overview of current efforts.
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Speziale P, Pietrocola G, Rindi S, Provenzano M, Provenza G, Di Poto A, Visai L, Arciola CR. Structural and functional role of Staphylococcus aureus surface components recognizing adhesive matrix molecules of the host. Future Microbiol 2009; 4:1337-52. [DOI: 10.2217/fmb.09.102] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus is a versatile and harmful human pathogen in both hospital- and community-acquired infections. S. aureus can initiate host infection by adhering to components of the extracellular matrix. Adherence is mediated by a variety of protein adhesins of the microbial surface component recognizing adhesive matrix molecule (MSCRAMM) family. In this article, we describe these MSCRAMMs in terms of structural organization and ligand-binding capacity and discuss their role as a possible target for immunotherapy.
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Affiliation(s)
- Pietro Speziale
- Department of Biochemistry, Viale Taramelli 3/b 27100 Pavia, Italy
| | | | - Simonetta Rindi
- Department of Biochemistry, Viale Taramelli 3/b 27100 Pavia, Italy
| | - Maria Provenzano
- Department of Biochemistry, Viale Taramelli 3/b 27100 Pavia, Italy
| | - Giulio Provenza
- Department of Biochemistry, Viale Taramelli 3/b 27100 Pavia, Italy
| | | | - Livia Visai
- Department of Biochemistry, Viale Taramelli 3/b 27100 Pavia, Italy and Center for Tissue Engineering (CIT), Via Ferrata 1, 27100 Pavia, Italy
| | - Carla Renata Arciola
- Research Unit on Implant Infections, Rizzoli Orthopaedic Institute, Via di Barbiano 1/10, 40136 Bologna, Italy and Experimental Pathology Department, University of Bologna, Via S. Giacomo 14, 40126 Bologna, Italy
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Broekhuizen CAN, de Boer L, Schipper K, Jones CD, Quadir S, Feldman RG, Vandenbroucke-Grauls CMJE, Zaat SAJ. The influence of antibodies on Staphylococcus epidermidis adherence to polyvinylpyrrolidone-coated silicone elastomer in experimental biomaterial-associated infection in mice. Biomaterials 2009; 30:6444-50. [PMID: 19716173 DOI: 10.1016/j.biomaterials.2009.08.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2009] [Accepted: 08/09/2009] [Indexed: 11/30/2022]
Abstract
Biomaterial-associated infection (BAI) is a major problem in modern medicine, and is often caused by Staphylococcus epidermidis. We aimed to raise monoclonal antibodies (mAbs) against major surface protein antigens of S. epidermidis, and to assess their possible protective activity in experimental BAI. Mice were vaccinated with a cell wall protein preparation of S. epidermidis. A highly immunodominant antigen was identified as Accumulation-associated protein (Aap). mAbs against Aap and against surface-exposed lipoteichoic acid (LTA) were used for passive immunization of mice in experimental biomaterial-associated infection. Neither anti-Aap nor anti-LTA mAbs showed protection. Either with or without antibodies, tissue surrounding the implants was more often culture positive than the implants themselves, but bacterial adherence to the implants was significantly increased in mice injected with anti-LTA. In vitro, anti-Aap and anti-LTA did show binding to S. epidermidis, but no opsonic activity was observed. We conclude that antibodies against S. epidermidis LTA or Aap showed no opsonic activity and did not protect mice against BAI. Moreover, the increase in binding to implanted biomaterial suggests that passive immunization may increase the risk for BAI.
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Affiliation(s)
- Corine A N Broekhuizen
- Department of Medical Microbiology, Center of Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
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Shah PS, Kaufman DA. Antistaphylococcal immunoglobulins to prevent staphylococcal infection in very low birth weight infants. Cochrane Database Syst Rev 2009:CD006449. [PMID: 19370635 DOI: 10.1002/14651858.cd006449.pub2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Nosocomial infection is a major problem affecting the immediate health and long-term outcome of preterm and very low birth weight neonates. More than half of these infections are caused by staphylococci. Various type specific antibodies targeted at different antigenic markers of Staphylococcus have been developed and have shown promise in animal studies. OBJECTIVES To evaluate the efficacy and safety of antistaphylococcal immunoglobulins in the prevention of Staphylococcal infection in very low birth weight infants. SEARCH STRATEGY Medline, Embase, CINAHL, Cochrane Central Register of Controlled Trials (The Cochrane Library) were searched from their inception until February 2009. In addition, abstracts of major pediatric meetings of last seven years were searched. SELECTION CRITERIA Randomized and quasi-randomized studies of antistaphylococcal immunoglobulins for the prevention of staphylococcal infections in preterm or very low birth weight neonates were reviewed by both authors for their eligibility for inclusion. Studies of any dose and/or route were included. Quality of studies was evaluated using criteria of masking of randomization, masking of intervention, completeness of follow-up and masking of outcome assessment by both review authors. DATA COLLECTION AND ANALYSIS Data from the primary author were obtained where published data provided inadequate information for the review or where relevant data could not be abstracted. Data were abstracted independently by both review authors. Statistical methods included calculation of relative risk (RR), risk difference (RD), number needed to treat (NNT) and weighted mean difference (WMD) when appropriate. Ninety five percent confidence intervals (CI) was used for these estimates of treatment effects. A fixed effect model was used for meta-analyses. MAIN RESULTS Three eligible studies were included (two studies of INH A-21 and one study of Altastaph involving a total of 2,701 neonates). Three reports of Pagibaximab were published as abstracts and will be considered for inclusion when further information is obtained. There were no significant differences noted in the risk of Staphylococcal infection between INH A-21 vs. placebo (typical RR 1.07, 95% CI 0.94, 1.22) or Altastaph vs. placebo (RR 0.86, 95% CI 0.32, 2.28); the risk of other bacterial infection between INH A-21 vs. placebo (typical RR 0.87, 95% CI 0.72, 1.06) or Altastaph vs. placebo (RR 0.93, 95% CI 0.53, 1.64); or the risk of any infection between INH A-21 vs. placebo (RR 1.00, 95% CI 0.91, 1.09) or Altastaph vs. placebo (RR 0.93, 95% CI 0.54, 1.62). There was no significant difference in the incidence of relevant secondary outcomes (chronic lung disease at 28 days, patent ductus arteriosus, necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity or duration of antibiotic and vancomycin use). AUTHORS' CONCLUSIONS Antistaphylococcal immunoglobulins (INH A-21 and Altastaph) are not recommended for prevention of staphylococcal infections in preterm or VLBW neonates. Further research to investigate the efficacy of other products such as Pagibaximab is needed.
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Affiliation(s)
- Prakeshkumar S Shah
- Department of Paediatrics and Department of Health Policy, Management and Evaluation, Rm 775A, University of Toronto, 600 University Avenue, Toronto, Ontario, Canada, M5G 1XB.
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Abstract
Staphylococcus aureus is an important pathogen in the hospital and in the community, and it is increasingly resistant to multiple antibiotics. A nonantimicrobial approach to controlling S aureus is needed. The most extensively tested vaccine against S aureus, which is a capsular polysaccharide-based vaccine known as StaphVAX, showed promise in an initial phase 3 trial, but was found to be ineffective in a confirmatory trial, leading to its development being halted. Likewise, a human IgG preparation known as INH-A21 (Veronate) with elevated levels of antibodies to the staphylococcal surface adhesins ClfA and SdrG made it into phase 3 testing, where it failed to show a clinical benefit. Several novel antigens are being tested for potential inclusion in a staphylococcal vaccine, including cell wall-anchored adhesin proteins and exotoxins. Given the multiple and sometimes redundant virulence factors of S aureus that enable it to be such a crafty pathogen, if a vaccine is to prove effective, it will have to be multicomponent, incorporating several surface proteins, toxoids, and surface polysaccharides.
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Affiliation(s)
- Adam C Schaffer
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, PBB-B-422, 75 Francis street, Boston, MA 02115, USA
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Schaffer AC, Lee JC. Vaccination and passive immunisation against Staphylococcus aureus. Int J Antimicrob Agents 2008; 32 Suppl 1:S71-8. [DOI: 10.1016/j.ijantimicag.2008.06.009] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Accepted: 06/09/2008] [Indexed: 10/21/2022]
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Xiong YQ, Bensing BA, Bayer AS, Chambers HF, Sullam PM. Role of the serine-rich surface glycoprotein GspB of Streptococcus gordonii in the pathogenesis of infective endocarditis. Microb Pathog 2008; 45:297-301. [PMID: 18656529 DOI: 10.1016/j.micpath.2008.06.004] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2008] [Revised: 06/26/2008] [Accepted: 06/27/2008] [Indexed: 01/06/2023]
Abstract
The direct binding of bacteria to platelets is a central interaction in the pathogenesis of infective endocarditis. GspB is a serine-rich, cell wall glycoprotein of Streptococcus gordonii that mediates the binding of this organism to human platelets in vitro. To assess the contribution of this adhesin to the pathogenesis of endocarditis, we compared the virulence of S. gordonii M99 (which expresses GspB) with an isogenic, gspB mutant (PS846) in two rat models of endovascular infection. In the first group of experiments, animals were infected intravenously with M99 or PS846, and sacrificed 72 h later, to assess levels of bacteria within cardiac vegetations, kidneys, and spleens. When inoculated with 10(5)CFU, rats infected with PS846 had significantly lower densities of organisms within vegetations (mean: 3.84 log(10)CFU/g) as compared with M99-infected rats (6.67 log(10)CFU/g; P<0.001). Marked differences were also seen in rats co-infected with M99 and PS846, at a 1:1 ratio. While M99 was found at high levels within vegetations, kidneys and spleens (mean log(10)CFU/g: 6.62, 5.07 and 4.18, respectively) PS846 was not detected within these tissues. Thus, platelet binding by GspB appears to be a major interaction in the pathogenesis of endocarditis due to S. gordonii.
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Affiliation(s)
- Yan Q Xiong
- Department of Medicine, Harbor-UCLA Medical Center, 1000W Carson Street, Building RB2, Torrance, CA 90502, USA
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Abstract
Staphylococcal infections represent an enormous burden to the public health system in the US and worldwide. While traditionally restricted to the hospital setting, highly virulent strains have recently emerged that may cause severe, even fatal, disease in healthy adults outside healthcare settings. This situation, together with the increasing resistance to many antibacterials in a wide variety of staphylococcal strains, requires that vaccine development for staphylococcal diseases be re-evaluated. Finding a vaccine for staphylococci is not trivial, as protective immunity to staphylococcal infections does not appear to exist at a significant degree, which may be partly due to the fact that our immune system is in constant contact with staphylococcal antigens and many strains are commensal organisms on human epithelia. Furthermore, the most virulent species, Staphylococcus aureus, produces protein A, a powerful means to evade acquired host defense. While two high-profile vaccine preparations have failed clinical trials within the last few years, promising results from novel approaches based on the combination of systematically selected antigens have been reported. These combinatory vaccines target microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), a family of bacterial proteins that bind to human extracellular matrix components. In addition, polysaccharide and other nonprotein antigens may represent suitable vaccine targets on the staphylococcal cell surface.
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Affiliation(s)
- Michael Otto
- Laboratory of Human Bacterial Pathogenesis, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, The National Institutes of Health, Hamilton, Montana 59840, USA.
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Expression of Staphylococcus epidermidis SdrG increases following exposure to an in vivo environment. Infect Immun 2008; 76:2950-7. [PMID: 18426874 DOI: 10.1128/iai.00055-08] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
SdrG is a surface-associated fibrinogen binding protein present in most strains of Staphylococcus epidermidis. Surface expression of SdrG was not detected by flow cytometry or immunofluorescence microscopy on S. epidermidis 0-47 grown in nutrient broth or in the presence of human serum. sdrG transcript levels increased 1 hour following a shift from growth in nutrient broth to growth in the bloodstream of a mouse and resulted in a concomitant increase in protein levels as detected by immunofluorescence microscopy. The environmental signal(s) resulting in the increase in expression is elusive, as growth under conditions known to mimic in vivo conditions (elevated CO(2), iron limitation, human serum, and citrated human blood) did not affect expression of SdrG. Immunizing mice with either the N1N2N3 (amino acids 50 to 597) or N2N3 (amino acids 273 to 597) subdomain of the N-terminal A domain of recombinant SdrG (rSdrG) elicited a robust antibody response; however, only mice vaccinated with rSdrG(N23) exhibited a significant reduction in 0-47 recovered after experimental infection. Since SdrG is expressed early during infection in response to specific host environmental cues present in the bloodstream and since antibodies to it are effective in reducing bacteremia, SdrG possesses attributes of a vaccine component effective against the pathogenic form of the ubiquitous human commensal S. epidermidis.
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Nagy E, Giefing C, von Gabain A. Anti-infective antibodies: a novel tool to prevent and treat nosocomial diseases. Expert Rev Anti Infect Ther 2008; 6:21-30. [PMID: 18251661 DOI: 10.1586/14787210.6.1.21] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The emergence of multidrug-resistant bacteria is a growing challenge for healthcare in the treatment of infectious diseases. In particular, nosocomial infections are getting out of control and reduce the likelihood to recover without, sometimes lethal, complications and long-term damage. Current antibiotics are unable to keep nosocomial infections in check and novel ones move only reluctantly forward and are expected to only delay the problem of multidrug resistance. Progress made in the identification of suitable pathogen targets, a better understanding of host-parasite interactions and the recent inclusion of monoclonal antibodies into the arsenal of novel therapies has provoked the interest to revitalize a historical concept of medicine to treat and prevent bacterial infections with antibodies.
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Affiliation(s)
- Eszter Nagy
- Intercell AG, Vienna Biocenter Campus 5/6, 1030 Vienna, Austria.
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Staphylococcus epidermidis Biofilms: Functional Molecules, Relation to Virulence, and Vaccine Potential. GLYCOSCIENCE AND MICROBIAL ADHESION 2008; 288:157-82. [DOI: 10.1007/128_2008_19] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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ter Meulen J. Monoclonal antibodies for prophylaxis and therapy of infectious diseases. Expert Opin Emerg Drugs 2007; 12:525-40. [PMID: 17979597 DOI: 10.1517/14728214.12.4.525] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Monoclonal antibodies (mAb) are attractive biologic drugs due to their exquisite specificity and well understood mechanisms of action, which results in a higher predictability and lower attrition rate compared with other drugs. Therefore, it may seem surprising that only a single mAb is presently marketed for an infectious disease indication. However, the antibiotic resistance crisis, emerging viral diseases and bioterroristic threats have recently spurred the development of anti-infective mAbs, of which more than a dozen are being tested in clinical trials. Conceptually, and validated in many preclinical models, mAbs will be most effective when used prophylactically against acute viral infections and bacterial toxins. The acute bacterial and chronic viral infections, which are medically and economically far more important, are much more difficult to control by antibodies, as the recent clinical failure of some polyclonal antibody products has shown. In these situations, the synergistic action of two or more mAbs together with a small molecule drug will most likely be required for therapeutic efficacy. This review aims to highlight the scientific and economic opportunities and obstacles that are encountered in the quest to add mAbs to the armament of anti-infective drugs.
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Affiliation(s)
- Jan ter Meulen
- Infectious Diseases, Crucell Holland BV, P.O. Box 2048, 2301, CA Leiden, The Netherlands.
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Abstract
Multiple resistant staphylococci that cause significant morbidity and mortality are the leading cause of nosocomial infections. Meanwhile, methicillin-resistant Staphylococcus aureus (MRSA) also spreads in the community, where highly virulent strains infect children and young adults who have no predisposing risk factors. Although some treatment options remain, the search for new antibacterial targets and lead compounds is urgently required to ensure that staphylococcal infections can be effectively treated in the future. Promising targets for new antibacterials are gene products that are involved in essential cell functions. In addition to antibacterials, active and passive immunization strategies are being developed that target surface components of staphylococci such as cell wall-linked adhesins, teichoic acids and capsule or immunodominant antigens.
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Affiliation(s)
- Knut Ohlsen
- University of Würzburg, Institute for Molecular Infection Biology, Röntgenring 11, 97070 Würzburg, Germany
| | - Udo Lorenz
- University of Würzburg, Centre for Operative Medicine, Department of Surgery I, Oberdürrbacher Str. 6, 97080 Würzburg, Germany
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DeJonge M, Burchfield D, Bloom B, Duenas M, Walker W, Polak M, Jung E, Millard D, Schelonka R, Eyal F, Morris A, Kapik B, Roberson D, Kesler K, Patti J, Hetherington S. Clinical trial of safety and efficacy of INH-A21 for the prevention of nosocomial staphylococcal bloodstream infection in premature infants. J Pediatr 2007; 151:260-5, 265.e1. [PMID: 17719934 DOI: 10.1016/j.jpeds.2007.04.060] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Revised: 03/30/2007] [Accepted: 04/25/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To determine if INH-A21, an intravenous immune globulin (IGIV) derived from donors with high titers of antibody to surface adhesins of Staphylococcus epidermidis and S. aureus prevents late-onset sepsis (LOS) in very low birth weight (VLBW) infants. STUDY DESIGN In this double-blind, placebo-controlled study, infants with birth weights 500 to 1250 g were randomized to receive up to four doses of INH-A21 (Veronate) or placebo. The primary objective was to determine the safety and efficacy of INH-A21 versus placebo for prevention of S. aureus LOS in VLBW infants. RESULTS A total of 1983 infants from 95 neonatal intensive care units were randomized, and received at least one dose of study drug. S. aureus LOS developed in 50 of 989 (5%) and 60 of 994 (6%) infants who received placebo or INH-A21, respectively (P = .34). No differences were found in the frequencies of LOS caused by coagulase-negative staphylococci (CoNS), Candida spp, or overall mortality. No adverse events were statistically significantly associated with INH-A21 infusions compared with placebo. CONCLUSION INH-A21 failed to reduce the incidence of staphylococcal LOS or candidemia in premature infants.
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Abstract
Staphylococci are among the most frequently encountered pathogens in both the inpatient and the outpatient setting. Management of infections caused by these organisms is complicated by the increasingly common resistance of staphylococcal pathogens to commonly used antibacterials. As a consequence, novel approaches to prevention and treatment are urgently required. Such approaches include the development of vaccines and immunoglobulin preparations targeted at virulence factors expressed in vivo by staphylococci. This article reviews the biopharmaceutical progress made to date in this field and suggests approaches to further progress.
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Mack D, Rohde H, Harris LG, Davies AP, Horstkotte MA, Knobloch JKM. Biofilm formation in medical device-related infection. Int J Artif Organs 2006; 29:343-59. [PMID: 16705603 DOI: 10.1177/039139880602900404] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Medical device-associated infections, most frequently caused by coagulase-negative staphylococci, especially Staphylococcus epidermidis, are of increasing importance in modern medicine. Regularly, antimicrobial therapy fails without removal of the implanted device. The most important factor in the pathogenesis of medical device-associated staphylococcal infections is the formation of adherent, multilayered bacterial biofilms. There is urgent need for an increased understanding of the functional factors involved in biofilm formation, the regulation of their expression, and the interaction of those potential virulence factors in device related infection with the host. Significant progress has been made in recent years which may ultimately lead to new rational approaches for better preventive, therapeutic, and diagnostic measures.
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Affiliation(s)
- D Mack
- Medical Microbiology and Infectious Diseases, The School of Medicine, University of Wales Swansea, Swansea, UK.
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Bloom BT. INH-A21: a donor-selected Staphylococcal human immune globulin for the prevention of late-onset neonatal Staphylococcal infection. Expert Opin Investig Drugs 2006; 15:703-7. [PMID: 16732720 DOI: 10.1517/13543784.15.6.703] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INH-A21 is an experimental human immune globulin for intravenous infusion (IGIV) derived from donors specifically selected for elevated levels of antibodies against the Staphylococcal fibrinogen-binding proteins, serine aspartate dipeptide repeat G and clumping factor A. Phase II results demonstrated that infusions of INH-A21 were well tolerated and there were no trends for increasing adverse events, or the common morbidities associated with prematurity. Enrollment has been completed in (but no results have been released from) a Phase III human trial testing INH-A21 as a prophylactic agent against staphylococcal infection in very low birth weight infants (500-1250 g).
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Affiliation(s)
- Barry T Bloom
- Department of Pediatrics, Kansas University School of Medicine--Wichita, Wesley Medical Centre, 550 North Hillside, Wichita, Kansas 67214, USA.
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