1
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Yu J, Han W, Xu Y, Shen L, Zhao H, Zhang J, Xiao Y, Guo Y, Yu F. Biofilm-producing ability of methicillin-resistant Staphylococcus aureus clinically isolated in China. BMC Microbiol 2024; 24:241. [PMID: 38961344 DOI: 10.1186/s12866-024-03380-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 06/18/2024] [Indexed: 07/05/2024] Open
Abstract
BACKGROUND Staphylococcus aureus, a commensal bacterium, colonizes the skin and mucous membranes of approximately 30% of the human population. Apart from conventional resistance mechanisms, one of the pathogenic features of S. aureus is its ability to survive in a biofilm state on both biotic and abiotic surfaces. Due to this characteristic, S. aureus is a major cause of human infections, with Methicillin-Resistant Staphylococcus aureus (MRSA) being a significant contributor to both community-acquired and hospital-acquired infections. RESULTS Analyzing non-repetitive clinical isolates of MRSA collected from seven provinces and cities in China between 2014 and 2020, it was observed that 53.2% of the MRSA isolates exhibited varying degrees of ability to produce biofilm. The biofilm positivity rate was notably high in MRSA isolates from Guangdong, Jiangxi, and Hubei. The predominant MRSA strains collected in this study were of sequence types ST59, ST5, and ST239, with the biofilm-producing capability mainly distributed among moderate and weak biofilm producers within these ST types. Notably, certain sequence types, such as ST88, exhibited a high prevalence of strong biofilm-producing strains. The study found that SCCmec IV was the predominant type among biofilm-positive MRSA, followed by SCCmec II. Comparing strains with weak and strong biofilm production capabilities, the positive rates of the sdrD and sdrE were higher in strong biofilm producers. The genetic determinants ebp, icaA, icaB, icaC, icaD, icaR, and sdrE were associated with strong biofilm production in MRSA. Additionally, biofilm-negative MRSA isolates showed higher sensitivity rates to cefalotin (94.8%), daptomycin (94.5%), mupirocin (86.5%), teicoplanin (94.5%), fusidic acid (81.0%), and dalbavancin (94.5%) compared to biofilm-positive MRSA isolates. The biofilm positivity rate was consistently above 50% in all collected specimen types. CONCLUSIONS MRSA strains with biofilm production capability warrant increased vigilance.
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Affiliation(s)
- Jingyi Yu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Weihua Han
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yanlei Xu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Li Shen
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Huilin Zhao
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Jiao Zhang
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yanghua Xiao
- School of Public Health, Nanchang University, Nanchang, Jiangxi, China
| | - Yinjuan Guo
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Fangyou Yu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China.
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2
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Ran W, Yue Y, Long F, Zhong K, Bai J, Xiao Y, Bu Q, Huang Y, Wu Y, Gao H. Antibacterial Mechanism of 2R,3R-Dihydromyricetin Against Staphylococcus aureus: Deciphering Inhibitory Effect on Biofilm and Virulence Based on Transcriptomic and Proteomic Analyses. Foodborne Pathog Dis 2023; 20:90-99. [PMID: 36862127 DOI: 10.1089/fpd.2022.0075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
Staphylococcus aureus is a major foodborne pathogen that leads to various diseases due to its biofilm and virulence factors. This study aimed to investigate the inhibitory effect of 2R,3R-dihydromyricetin (DMY), a natural flavonoid compound, on the biofilm formation and virulence of S. aureus, and to explore the mode of action using transcriptomic and proteomic analyses. Microscopic observation revealed that DMY could remarkably inhibit the biofilm formation by S. aureus, leading to a collapse on the biofilm architecture and a decrease in viability of biofilm cell. Moreover, the hemolytic activity of S. aureus was reduced to 32.7% after treatment with subinhibitory concentration of DMY (p < 0.01). Bioinformation analysis based on RNA-sequencing and proteomic profiling revealed that DMY induced 262 differentially expressed genes and 669 differentially expressed proteins (p < 0.05). Many downregulated genes and proteins related to surface proteins were involved in biofilm formation, including clumping factor A (ClfA), iron-regulated surface determinants (IsdA, IsdB, and IsdC), fibrinogen-binding proteins (FnbA, FnbB), and serine protease. Meanwhile, DMY regulated a wide range of genes and proteins enriched in bacterial pathogenesis, cell envelope, amino acid metabolism, purine and pyrimidine metabolism, and pyruvate metabolism. These findings suggest that DMY targets S. aureus through multifarious mechanisms, and especially prompt that interference of surface proteins in cell envelope would lead to attenuation of biofilm and virulence.
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Affiliation(s)
- Wenyi Ran
- Department of Food Engineering, College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, China
| | - Yuxi Yue
- Department of Food Engineering, College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, China
| | - Feiwu Long
- Department of Hygienic Toxicology and Pathology, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China.,Research Center for Nutrition, Metabolism and Food Safety, West China-PUMC C.C. Chen Institute of Health, Sichuan University, Chengdu, China
| | - Kai Zhong
- Department of Food Engineering, College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, China
| | - Jinrong Bai
- Department of Hygienic Toxicology and Pathology, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China.,Research Center for Nutrition, Metabolism and Food Safety, West China-PUMC C.C. Chen Institute of Health, Sichuan University, Chengdu, China
| | - Yue Xiao
- Department of Hygienic Toxicology and Pathology, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China.,Research Center for Nutrition, Metabolism and Food Safety, West China-PUMC C.C. Chen Institute of Health, Sichuan University, Chengdu, China
| | - Qian Bu
- Department of Hygienic Toxicology and Pathology, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China.,Research Center for Nutrition, Metabolism and Food Safety, West China-PUMC C.C. Chen Institute of Health, Sichuan University, Chengdu, China
| | - Yina Huang
- Department of Hygienic Toxicology and Pathology, West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, China.,Research Center for Nutrition, Metabolism and Food Safety, West China-PUMC C.C. Chen Institute of Health, Sichuan University, Chengdu, China
| | - Yanping Wu
- Department of Food Engineering, College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, China
| | - Hong Gao
- Department of Food Engineering, College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu, China
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3
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Haag AF, Liljeroos L, Donato P, Pozzi C, Brignoli T, Bottomley MJ, Bagnoli F, Delany I. In Vivo Gene Expression Profiling of Staphylococcus aureus during Infection Informs Design of Stemless Leukocidins LukE and -D as Detoxified Vaccine Candidates. Microbiol Spectr 2023; 11:e0257422. [PMID: 36688711 PMCID: PMC9927290 DOI: 10.1128/spectrum.02574-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 01/02/2023] [Indexed: 01/24/2023] Open
Abstract
Staphylococcus aureus is a clinically important bacterial pathogen that has become resistant to treatment with most routinely used antibiotics. Alternative strategies, such as vaccination and phage therapy, are therefore actively being investigated to prevent or combat staphylococcal infections. Vaccination requires that vaccine targets are expressed at sufficient quantities during infection so that they can be targeted by the host's immune system. While our knowledge of in vitro expression levels of putative vaccine candidates is comprehensive, crucial in vivo expression data are scarce and promising vaccine candidates during in vitro assessment often prove ineffective in preventing S. aureus infection. Here, we show how a newly developed high-throughput quantitative reverse transcription-PCR (qRT-PCR) assay monitoring the expression of 84 staphylococcal genes encoding mostly virulence factors can inform the selection and design of effective vaccine candidates against staphylococcal infections. We show that this assay can accurately quantify mRNA expression levels of these genes in several host organs relying only on very limited amounts of bacterial mRNA in each sample. We selected two highly expressed genes, lukE and lukD, encoding pore-forming leukotoxins, to inform the design of detoxified recombinant proteins and showed that immunization with recombinant genetically detoxified LukED antigens conferred protection against staphylococcal skin infection in mice. Consequently, knowledge of in vivo-expressed virulence determinants can be successfully deployed to identify and select promising candidates for optimized design of effective vaccine antigens against S. aureus. Notably, this approach should be broadly applicable to numerous other pathogens. IMPORTANCE Vaccination is an attractive strategy for preventing bacterial infections in an age of increased antimicrobial resistance. However, vaccine development frequently suffers significant setbacks when candidate antigens that show promising results in in vitro experimentation fail to protect from disease. An alluring strategy is to focus resources on developing bacterial virulence factors that are expressed during disease establishment or maintenance and are critical for bacterial in-host survival as vaccine targets. While expression profiles of many virulence factors have been characterized in detail in vitro, our knowledge of their in vivo expression profiles is still scarce. Here, using a high-throughput qRT-PCR approach, we identified two highly expressed leukotoxins in a murine infection model and showed that genetically detoxified derivatives of these elicited a protective immune response in a murine skin infection model. Therefore, in vivo gene expression can inform the selection of promising candidates for the design of effective vaccine antigens.
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Affiliation(s)
- Andreas F. Haag
- GSK, Siena, Italy
- School of Medicine, University of St. Andrews, St. Andrews, United Kingdom
| | | | | | | | - Tarcisio Brignoli
- GSK, Siena, Italy
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
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4
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Poh SE, Koh WL, Lim SYD, Wang EC, Yew YW, Common JE, Oon HH, Li H. Expression of Staphylococcus aureus virulence factors in atopic dermatitis. JID INNOVATIONS 2022; 2:100130. [PMID: 35860448 PMCID: PMC9289736 DOI: 10.1016/j.xjidi.2022.100130] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 03/23/2022] [Accepted: 03/28/2022] [Indexed: 11/29/2022] Open
Abstract
Atopic dermatitis (AD) is a skin inflammatory disease in which the opportunistic pathogen Staphylococcus aureus is prevalent and abundant. S. aureus harbors several secreted virulence factors that have well-studied functions in infection models, but it is unclear whether these extracellular microbial factors are relevant in the context of AD. To address this question, we designed a culture-independent method to detect and quantify S. aureus virulence factors expressed at the skin sites. We utilized RNase-H‒dependent multiplex PCR for preamplification of reverse-transcribed RNA extracted from tape strips of patients with AD sampled at skin sites with differing severity and assessed the expression of a panel of S. aureus virulence factors using qPCR. We observed an increase in viable S. aureus abundance on sites with increased severity of disease, and many virulence factors were expressed at the AD skin sites. Surprisingly, we did not observe any significant upregulation of the virulence factors at the lesional sites compared with those at the nonlesional control. Overall, we utilized a robust assay to directly detect and quantify viable S. aureus and its associated virulence factors at the site of AD skin lesions. This method can be extended to study the expression of skin microbial genes at the sites of various dermatological conditions.
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Affiliation(s)
- Si En Poh
- Molecular Engineering Lab, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research, Singapore, Singapore
| | - Winston L.C. Koh
- Molecular Engineering Lab, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research, Singapore, Singapore
| | - Shi Yu Derek Lim
- National Skin Centre, National Healthcare Group, Singapore, Singapore
| | - Etienne C.E. Wang
- National Skin Centre, National Healthcare Group, Singapore, Singapore
- Skin Research Institute of Singapore, Singapore
| | - Yik Weng Yew
- National Skin Centre, National Healthcare Group, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - John E.A. Common
- ASTAR Skin Research Labs (ASRL), Agency for Science, Technology and Research, Singapore, Singapore
| | - Hazel H. Oon
- National Skin Centre, National Healthcare Group, Singapore, Singapore
| | - Hao Li
- Molecular Engineering Lab, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research, Singapore, Singapore
- Department of Chemistry, Faculty of Science, National University of Singapore, Singapore, Singapore
- Correspondence: Hao Li, Department of Chemistry, Faculty of Science, National University of Singapore, 4 Science Drive 2, S9 Level 12, Singapore 117544, Singapore.
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5
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Detection of capsular genotypes of methicillin-resistant Staphylococcus aureus and clonal distribution of the cap5 and cap8 genes in clinical isolates. Arch Microbiol 2022; 204:186. [PMID: 35192046 PMCID: PMC8861481 DOI: 10.1007/s00203-022-02793-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 01/22/2022] [Accepted: 02/03/2022] [Indexed: 11/29/2022]
Abstract
Up until now, the capsular polysaccharides of Staphylococcus aureus have been classified into 11 types, of which only 2 types 5 and 8; (encoded by the genes cap5 and cap8, respectively) are present in 80–90% of clinically significant strains. The aim of the present study was to detect the capsular genotypes of methicillin-resistant S. aureus (MRSA) clinical isolates and determined their clonal distribution. A total of 262 MRSA clinical isolates from different hospitals in Mexico were analyzed by PCR to determine the genetic characteristics of their capsule expression. Pulsed-field gel electrophoresis and multilocus sequence typing were used to characterize the isolates. The analysis of the capsular genotypes among MRSA isolates showed that 245 isolates (93.5%) contained the cap5 gene, and that the remaining 17 (6.5%) encoded the cap8 gene. The MRSA isolates were grouped into four clonal groups. The identification of the capsular genotypes of clinical isolates of MRSA is important information because potential vaccine formulations against S. aureus involve capsular polysaccharides.
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6
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Combinations of Peptide-Protein Extracts from Native Probiotics Suppress the Growth of Multidrug-Resistant Staphylococcus aureus and Citrobacter freundii via Membrane Perturbation and Ultrastructural Changes. Antibiotics (Basel) 2022; 11:antibiotics11020154. [PMID: 35203757 PMCID: PMC8868453 DOI: 10.3390/antibiotics11020154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/21/2022] [Accepted: 01/23/2022] [Indexed: 11/16/2022] Open
Abstract
The occurrence of multidrug-resistant pathogens in the food chain causes health problems in humans, thus, research for novel antimicrobials to combat their growth is of interest. This study evaluates the antimicrobial potential of several combinations of peptide-protein extracts (PCs) consisting of peptide extracts from three native probiotic strains, Lactiplantibacillus plantarum UTNGt2, Lactococcus lactis UTNGt28, and L. plantarum UTNGt21A, alone or in combination with EDTA (ethylenediaminetetraacetic acid) against multidrug-resistant Staphylococcus aureus ATCC1026 and Citrobacter freundii UTNB3Sm1. Based on the antimicrobial assay, among the 19 tested PCs, two (PC11 and PC17) produced a greater zone of inhibition against both pathogens in vitro. Time-killing assays indicated the rapid death of S. aureus after exposure to PC11 and PC17, while C. freundii was rapidly inhibited by PC11 and PC1 (UTNGt2 only), suggesting that the inhibitory action is pathogen and dose-dependent of a particular molecule present in the extract. A marginal inhibitory effect was observed when the peptides were combined with EDTA. Transmission electron microscopy (TEM) revealed the structural membrane damage of both target strains upon interaction with individual peptide extracts. Different degrees of cell deformation, condensed cytoplasm, membrane blebbing, and ghost cell formation with visibly broken cell walls were observed in S. aureus. Likewise, the separation of the cytoplasmic membrane from the outer membrane, ghost cells, along with ovoid and deformed cells with undulated cell walls were observed for C. freundii. Furthermore, scanning electronic microscopy (SEM) analysis revealed different wrinkled and deformed cells covered by debris. A leakage of aromatic molecules was detected for both pathogens, indicating that PCs disrupted the cell wall integrity, inducing cell death. Given their inhibitory action and capacity to induce damage of the cytoplasmic membrane, the selected PCs may serve to slow bacterial growth in vitro; further research is required to prove their efficiency ex vitro to battle against food poisoning and subsequent human infection.
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7
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Leite EL, Oliveira AFDE, Carmo FLRDO, Berkova N, Barh D, Ghosh P, Azevedo V. Bacteriocins as an alternative in the treatment of infections by Staphylococcus aureus. AN ACAD BRAS CIENC 2020; 92:e20201216. [PMID: 33084762 DOI: 10.1590/0001-3765202020201216] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 08/18/2020] [Indexed: 01/19/2023] Open
Abstract
Staphylococcus aureus (S. aureus) is a highly versatile Gram-positive bacterium that is carried asymptomatically by up to 30% of healthy people, while being a major cause of healthcare-associated infections, making it a worldwide problem in clinical medicine. The adaptive evolution of S. aureus strains is demonstrated by its remarkable capacity to promptly develop high resistance to multiple antibiotics, thus limiting treatment choice. Nowadays, there is a continuous demand for an alternative to the use of antibiotics for S. aureus infections and a strategy to control the spread or to kill phylogenetically related strains. In this scenario, bacteriocins fit as with a promising and interesting alternative. These molecules are produced by a range of bacteria, defined as ribosomally synthesized peptides with bacteriostatic or bactericidal activity against a wide range of pathogens. This work reviews ascertained the main antibiotic-resistance mechanisms of S. aureus strains and the current, informative content concerning the applicability of the use of bacteriocins overlapping the use of conventional antibiotics in the context of S. aureus infections. Besides, we highlight the possible application of these biomolecules on an industrial scale in future work.
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Affiliation(s)
- Elma L Leite
- Institut National de la Recherche Agronomique (INRA), 65 Rue de Saint-Brieuc, 35000 Rennes, France.,Departamento de Genética, Ecologia e Evolução, ICB/UFMG, Av. Antonio Carlos, 6627, Pampulha, Caixa Postal 486, 31270-901 Belo Horizonte, MG, Brazil
| | - Alberto F DE Oliveira
- Institut National de la Recherche Agronomique (INRA), 65 Rue de Saint-Brieuc, 35000 Rennes, France
| | - Fillipe L R DO Carmo
- Departamento de Genética, Ecologia e Evolução, ICB/UFMG, Av. Antonio Carlos, 6627, Pampulha, Caixa Postal 486, 31270-901 Belo Horizonte, MG, Brazil
| | - Nadia Berkova
- Institut National de la Recherche Agronomique (INRA), 65 Rue de Saint-Brieuc, 35000 Rennes, France
| | - Debmalya Barh
- Centre for Genomics and Applied Gene Technology, Institute of Integrative Omics and Applied Biotechnology (IIOAB), Nonakuri, Purba Medinipur, 721172 West Bengal, India
| | - Preetam Ghosh
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA-23284, USA
| | - Vasco Azevedo
- Departamento de Genética, Ecologia e Evolução, ICB/UFMG, Av. Antonio Carlos, 6627, Pampulha, Caixa Postal 486, 31270-901 Belo Horizonte, MG, Brazil
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8
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Liu X, Yue Y, Wu Y, Zhong K, Bu Q, Gao H. Discovering the antibacterial mode of action of 3‐
p
‐
trans
‐coumaroyl‐2‐hydroxyquinic acid, a natural phenolic compound, against
Staphylococcus aureus
through an integrated transcriptomic and proteomic approach. J Food Saf 2020. [DOI: 10.1111/jfs.12861] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Xiaoyan Liu
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center Sichuan University Chengdu China
| | - Yuxi Yue
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center Sichuan University Chengdu China
| | - Yanping Wu
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center Sichuan University Chengdu China
- Key Laboratory of Food Science and Technology of Ministry of Education of Sichuan Province Sichuan University Chengdu China
| | - Kai Zhong
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center Sichuan University Chengdu China
- Key Laboratory of Food Science and Technology of Ministry of Education of Sichuan Province Sichuan University Chengdu China
| | - Qian Bu
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center Sichuan University Chengdu China
- Key Laboratory of Food Science and Technology of Ministry of Education of Sichuan Province Sichuan University Chengdu China
| | - Hong Gao
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center Sichuan University Chengdu China
- Key Laboratory of Food Science and Technology of Ministry of Education of Sichuan Province Sichuan University Chengdu China
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9
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Creech CB, Frenck RW, Fiquet A, Feldman R, Kankam MK, Pathirana S, Baber J, Radley D, Cooper D, Eiden J, Gruber WC, Jansen KU, Anderson AS, Gurtman A. Persistence of Immune Responses Through 36 Months in Healthy Adults After Vaccination With a Novel Staphylococcus aureus 4-Antigen Vaccine (SA4Ag). Open Forum Infect Dis 2019; 7:ofz532. [PMID: 31993453 PMCID: PMC6978999 DOI: 10.1093/ofid/ofz532] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/11/2019] [Indexed: 12/19/2022] Open
Abstract
Background Staphylococcus aureus causes serious health care- and community-associated disease, requiring improved preventive measures such as vaccines. The investigational S. aureus 4-antigen vaccine (SA4Ag), comprising capsular polysaccharide serotypes 5 and 8 (CP5 and CP8) conjugated to CRM197, recombinant mutant clumping factor A (rmClfA), and recombinant manganese transporter protein C (rP305A or rMntC), was well tolerated, inducing robust functional immune responses to all 4 antigens through 12 months postvaccination. This is a serological extension study through 36 months postvaccination. Methods In 2 previous studies, healthy adults received SA4Ag, SA3Ag (without rMntC), or placebo; serology was also assessed at ~24 and ~36 months postvaccination. Functional immune responses (antibody responses that facilitate killing of S. aureus or neutralize S. aureus virulence mechanisms) were assessed with opsonophagocytic activity killing assays (CP5 or CP8) and a fibrinogen-binding inhibition assay (ClfA). A competitive Luminex immunoassay assessed ClfA and rMntC responses. Adverse events within 48 hours of blood draw were recorded. Results Four hundred forty subjects (18-64 years old, 255; 65-85 years old, 185) were enrolled. At 24 and 36 months postvaccination, subjects receiving SA4Ag had substantially higher geometric mean titers (GMTs) for CP5, CP8, and ClfA vs baseline; geometric mean fold rises (GMFRs) from baseline to month 36 were 2.7-8.1. For rMntC, 36-month GMTs declined from peak levels but remained above baseline for all SA4Ag groups; GMFRs from baseline to month 36 were 1.8 and 1.5 in the younger and older cohorts, respectively. Conclusions Persistent functional immune responses to S. aureus antigens were observed through 36 months in healthy adults. ClinicalTrialsgov NCT01643941 and NCT01364571.
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Affiliation(s)
- C Buddy Creech
- Vanderbilt University School of Medicine and the Monroe Carell Jr. Children's Hospital, Nashville, Tennessee, USA
| | - Robert W Frenck
- Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Anne Fiquet
- Pfizer Vaccines Research & Development, Hurley, Berkshire, UK
| | - Robert Feldman
- QPS-MRA, Miami Research Associates LLC, Miami, Florida, USA
| | - Martin K Kankam
- Vince and Associates Clinical Research, Overland Park, Kansas, USA
| | - Sudam Pathirana
- Pfizer Vaccines Research & Development, Pearl River, New York, USA
| | - James Baber
- Pfizer Vaccines Research & Development, Sydney, New South Wales, Australia
| | - David Radley
- Pfizer Vaccines Research & Development, Pearl River, New York, USA
| | - David Cooper
- Pfizer Vaccines Research & Development, Pearl River, New York, USA
| | - Joseph Eiden
- Pfizer Vaccines Research & Development, Pearl River, New York, USA
| | - William C Gruber
- Pfizer Vaccines Research & Development, Pearl River, New York, USA
| | - Kathrin U Jansen
- Pfizer Vaccines Research & Development, Pearl River, New York, USA
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10
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Marshall HS, Baber J, Richmond P, Nissen M, Shakib S, Kreiswirth BN, Zito ET, Severs J, Eiden J, Gruber W, Jansen KU, Jones CH, Anderson AS. S. aureus colonization in healthy Australian adults receiving an investigational S. aureus 3-antigen vaccine. J Infect 2019; 79:582-592. [PMID: 31585191 DOI: 10.1016/j.jinf.2019.09.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/09/2019] [Accepted: 09/27/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Assess Staphylococcus aureus (S. aureus) colonization in healthy Australian adults receiving an investigational S. aureus 3-antigen vaccine (SA3Ag). METHODS In this phase 1, double-blind, sponsor-unblinded study, participants were randomized to receive a single dose (1 of 3 dose levels) of SA3Ag or placebo and a booster dose or placebo at 6 months. S. aureus isolates from nasal, perineal, and oropharyngeal swabs before and through 12 months post-vaccination were identified. RESULTS Baseline S. aureus colonization prevalence was 30.6% (any site), with nasal carriage (27.0%) more common than oropharyngeal/perineal (3.2% each). Following initial vaccination (low-dose: 102; mid-dose: 101; high-dose: 101; placebo: 102) and booster (low-dose: 45; mid-dose: 44; high-dose: 27; placebo: 181), placebo and SA3Ag groups showed similar S. aureus carriage through 12 months. Most colonized participants (74.0%) were colonized by single spa types. Placebo and SA3Ag groups had similar persistence of colonization, with 19.6-30.7% due to single spa types. Acquisition was observed in mid- and high-dose recipients (∼20%) and low-dose and placebo recipients (∼12%). Vaccination resulted in substantial increases in antibodies to all 3 antigens, irrespective of carriage status. CONCLUSIONS Based on descriptive analyses of this small study, SA3Ag vaccination did not impact S. aureus acquisition or carriage. Carriage status did not impact antibody responses to SA3Ag.
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Affiliation(s)
- Helen S Marshall
- Vaccinology and Immunology Research Trials Unit, Women's and Children's Hospital and Robinson Research Institute and Adelaide Medical School, The University of Adelaide, Adelaide, SA, Australia.
| | - James Baber
- Pfizer Australia Pty Ltd, Sydney, NSW, Australia
| | - Peter Richmond
- Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia Division of Paediatrics & Vaccine Trials Group, Perth, WA, Australia
| | - Michael Nissen
- Queensland Paediatric Infectious Diseases Laboratory, Children's Health Research Centre, University of Queensland, Queensland Children's Hospital, South Brisbane, Qld, Australia
| | - Sepehr Shakib
- Department of Clinical Pharmacology, University of Adelaide, Adelaide, SA, Australia
| | | | - Edward T Zito
- Pfizer Vaccine Research and Development, Collegeville, PA, USA
| | - Joseph Severs
- Pfizer Vaccine Research and Development, Pearl River, NY, USA
| | - Joseph Eiden
- Pfizer Vaccine Research and Development, Pearl River, NY, USA
| | - William Gruber
- Pfizer Vaccine Research and Development, Pearl River, NY, USA
| | | | - C Hal Jones
- Pfizer Vaccine Research and Development, Pearl River, NY, USA
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11
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Lin L, Agyemang K, Abdel‐Samie MA, Cui H. Antibacterial mechanism of
Tetrapleura tetraptera
extract against
Escherichia coli
and
Staphylococcus aureus
and its application in pork. J Food Saf 2019. [DOI: 10.1111/jfs.12693] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Lin Lin
- School of Food and Biological EngineeringJiangsu University Zhenjiang China
| | - Kwabena Agyemang
- School of Food and Biological EngineeringJiangsu University Zhenjiang China
| | | | - Haiying Cui
- School of Food and Biological EngineeringJiangsu University Zhenjiang China
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12
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Ansari S, Jha RK, Mishra SK, Tiwari BR, Asaad AM. Recent advances in Staphylococcus aureus infection: focus on vaccine development. Infect Drug Resist 2019; 12:1243-1255. [PMID: 31190912 PMCID: PMC6526327 DOI: 10.2147/idr.s175014] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 04/19/2019] [Indexed: 12/17/2022] Open
Abstract
Staphylococcus aureus normally colonizes the nasal cavity and pharynx. After breaching the normal habitat, the organism is able to cause a number of infections at any site of the body. The development of antibiotic resistance has created a global challenge for treating infections. Therefore, protection by vaccines may provide valuable measures. Currently, several vaccine candidates have been prepared which are either in preclinical phase or in early clinical phase, whereas several candidates have failed to show a protective efficacy in human subjects. Approaches have also been made in the development of monoclonal or polyclonal antibodies for passive immunization to protect from S. aureus infections. Therefore, in this review we have summarized the findings of recently published scientific literature to make a concise report.
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Affiliation(s)
- Shamshul Ansari
- Department of Microbiology, Chitwan Medical College and Teaching Hospital, Bharatpur, Chitwan, Nepal
| | - Rajesh Kumar Jha
- Department of Systems and Diseases (Pharmacology), Saba University School of Medicine, Saba, Dutch Caribbean
| | - Shyam Kumar Mishra
- Department of Microbiology, Maharajgunj Medical Campus, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal
| | | | - Ahmed Morad Asaad
- Department of Microbiology, Faculty of Medicine, Zagazig University, Zagazig, Egypt
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13
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Haynes J, Perry V, Benson E, Meeks A, Watts G, Watkins H, Braun R. In Depth Breadth Analyses of Human Blockade Responses to Norovirus and Response to Vaccination. Viruses 2019; 11:v11050392. [PMID: 31035476 PMCID: PMC6563306 DOI: 10.3390/v11050392] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/12/2019] [Accepted: 04/23/2019] [Indexed: 12/19/2022] Open
Abstract
To evaluate and understand the efficacy of vaccine candidates, supportive immunological measures are needed. Critical attributes for a norovirus vaccine are the strength and breadth of antibody responses against the many different genotypes. In the absence of suitable neutralization assays to test samples from vaccine clinical trials, blockade assays offer a method that can measure functional antibodies specific for many of the different norovirus strains. This paper describes development and optimization of blockade assays for an extended panel of 20 different norovirus strains that can provide robust and reliable data needed for vaccine assessment. The blockade assays were used to test a panel of human clinical samples taken before and after vaccination with the Takeda TAK-214 norovirus vaccine. Great variability was evident in the repertoire of blocking antibody responses prevaccination and postvaccination among individuals. Following vaccination with TAK-214, blocking antibody levels were enhanced across a wide spectrum of different genotypes. The results indicate that adults may have multiple exposures to norovirus and that the magnitude and breadth of the complex preexisting antibody response can be boosted and expanded by vaccination.
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Affiliation(s)
- Joel Haynes
- Vaccines Discovery Research, Takeda Pharmaceuticals, Cambridge, MA 02139, USA.
| | - Virginia Perry
- Vaccines Discovery Research, Takeda Pharmaceuticals, Cambridge, MA 02139, USA.
| | - Evelyn Benson
- Vaccines Discovery Research, Takeda Pharmaceuticals, Cambridge, MA 02139, USA.
| | - Alisa Meeks
- Vaccines Discovery Research, Takeda Pharmaceuticals, Cambridge, MA 02139, USA.
| | - Gayle Watts
- Vaccines Discovery Research, Takeda Pharmaceuticals, Cambridge, MA 02139, USA.
| | - Heather Watkins
- Vaccines Discovery Research, Takeda Pharmaceuticals, Cambridge, MA 02139, USA.
| | - Ralph Braun
- Vaccines Discovery Research, Takeda Pharmaceuticals, Cambridge, MA 02139, USA.
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14
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The genesis and evolution of bead-based multiplexing. Methods 2019; 158:2-11. [DOI: 10.1016/j.ymeth.2019.01.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 12/10/2018] [Accepted: 01/14/2019] [Indexed: 12/22/2022] Open
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15
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Mohamed N, Timofeyeva Y, Jamrozy D, Rojas E, Hao L, Silmon de Monerri NC, Hawkins J, Singh G, Cai B, Liberator P, Sebastian S, Donald RGK, Scully IL, Jones CH, Creech CB, Thomsen I, Parkhill J, Peacock SJ, Jansen KU, Holden MTG, Anderson AS. Molecular epidemiology and expression of capsular polysaccharides in Staphylococcus aureus clinical isolates in the United States. PLoS One 2019; 14:e0208356. [PMID: 30641545 PMCID: PMC6331205 DOI: 10.1371/journal.pone.0208356] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 11/15/2018] [Indexed: 12/14/2022] Open
Abstract
Staphylococcus aureus capsular polysaccharides (CP) are important virulence factors under evaluation as vaccine antigens. Clinical S. aureus isolates have the biosynthetic capability to express either CP5 or CP8 and an understanding of the relationship between CP genotype/phenotype and S. aureus epidemiology is valuable. Using whole genome sequencing, the clonal relatedness and CP genotype were evaluated for disease-associated S. aureus isolates selected from the Tigecycline Evaluation and Surveillance Trial (T.E.S.T) to represent different geographic regions in the United States (US) during 2004 and 2009–10. Thirteen prominent clonal complexes (CC) were identified, with CC5, 8, 30 and 45 representing >80% of disease isolates. CC5 and CC8 isolates were CP type 5 and, CC30 and CC45 isolates were CP type 8. Representative isolates from prevalent CC were susceptible to in vitro opsonophagocytic killing elicited by anti-CP antibodies, demonstrating that susceptibility to opsonic killing is not linked to the genetic lineage. However, as not all S. aureus isolates may express CP, isolates representing the diversity of disease isolates were assessed for CP production. While approximately 35% of isolates (primarily CC8) did not express CP in vitro, CP expression could be clearly demonstrated in vivo for 77% of a subset of these isolates (n = 20) despite the presence of mutations within the capsule operon. CP expression in vivo was also confirmed indirectly by measuring an increase in CP specific antibodies in mice infected with CP5 or CP8 isolates. Detection of antigen expression in vivo in relevant disease states is important to support the inclusion of these antigens in vaccines. Our findings confirm the validity of CP as vaccine targets and the potential of CP-based vaccines to contribute to S. aureus disease prevention.
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Affiliation(s)
- Naglaa Mohamed
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Yekaterina Timofeyeva
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Dorota Jamrozy
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Eduardo Rojas
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Li Hao
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | | | - Julio Hawkins
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Guy Singh
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Bing Cai
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Paul Liberator
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Shite Sebastian
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Robert G. K. Donald
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - Ingrid L. Scully
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - C. Hal Jones
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | - C. Buddy Creech
- Vanderbilt Vaccine Research Program, Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Isaac Thomsen
- Vanderbilt Vaccine Research Program, Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Julian Parkhill
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Sharon J. Peacock
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kathrin U. Jansen
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
| | | | - Annaliesa S. Anderson
- Pfizer Vaccine Research and Development, Pearl River, New York, United States of America
- * E-mail:
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16
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Bai JR, Wu YP, Elena G, Zhong K, Gao H. Insight into the effect of quinic acid on biofilm formed byStaphylococcus aureus. RSC Adv 2019; 9:3938-3945. [PMID: 35518066 PMCID: PMC9060517 DOI: 10.1039/c8ra09136f] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Accepted: 01/22/2019] [Indexed: 01/08/2023] Open
Abstract
The biofilm formation of Staphylococcus aureus on food contact surfaces is the main risk of food contamination. In the present study, we firstly investigated the inhibitory effect of quinic acid (QA) on biofilm formed by S. aureus. Crystal violet staining assay and microscopy analysis clearly showed that QA at sub-MIC concentrations was able to significantly reduce the biofilm biomass and cause a collapse on biofilm architecture. Meanwhile, fibrinogen binding assay showed that QA had obviously effect on the S. aureus bacteria adhesion. XTT reduction assay and confocal laser scanning microscopic images revealed that QA significantly decreased metabolic activity and viability of biofilm cells. In addition, qRT-PCR analysis explored the potential inhibitory mechanism of QA against biofilm formation, which indicated that QA significantly repressed the gene sarA and activated the gene agrA. Moreover, QA exhibited a highly ability to reduce the number of sessile S. aureus cells adhered on the stainless steel. So, it was suggested that QA could be used as a promising antibiofilm agent to control biofilm formation of S. aureus. QA effectively inhibited S. aureus biofilm formation. The key genes of biofilm inhibition induced by QA were agrA and sarA.![]()
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Affiliation(s)
- Jin-Rong Bai
- College of Light Industry
- Textile and Food Engineering and Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Yan-Ping Wu
- College of Light Industry
- Textile and Food Engineering and Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Grosu Elena
- College of Light Industry
- Textile and Food Engineering and Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Kai Zhong
- College of Light Industry
- Textile and Food Engineering and Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- P. R. China
| | - Hong Gao
- College of Light Industry
- Textile and Food Engineering and Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- P. R. China
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17
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Gurtman A, Begier E, Mohamed N, Baber J, Sabharwal C, Haupt RM, Edwards H, Cooper D, Jansen KU, Anderson AS. The development of a staphylococcus aureus four antigen vaccine for use prior to elective orthopedic surgery. Hum Vaccin Immunother 2018; 15:358-370. [PMID: 30215582 DOI: 10.1080/21645515.2018.1523093] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Staphylococcus aureus (S. aureus) is a challenging bacterial pathogen which can cause a range of diseases, from mild skin infections, to more serious and invasive disease including deep or organ space surgical site infections, life-threatening bacteremia, and sepsis. S. aureus rapidly develops resistance to antibiotic treatments. Despite current infection control measures, the burden of disease remains high. The most advanced vaccine in clinical development is a 4 antigen S. aureus vaccine (SA4Ag) candidate that is being evaluated in a phase 2b/3 efficacy study in patients undergoing elective spinal fusion surgery (STaphylococcus aureus suRgical Inpatient Vaccine Efficacy [STRIVE]). SA4Ag has been shown in early phase clinical trials to be generally safe and well tolerated, and to induce high levels of bactericidal antibodies in healthy adults. In this review we discuss the design of SA4Ag, as well as the proposed clinical development plan supporting licensure of SA4Ag for the prevention of invasive disease caused by S. aureus in elective orthopedic surgical populations. We also explore the rationale for the generalizability of the results of the STRIVE efficacy study (patients undergoing elective open posterior multilevel instrumented spinal fusion surgery) to a broad elective orthopedic surgery population due to the common pathophysiology of invasive S. aureus disease and commonalties of patient and procedural risk factors for developing postoperative S. aureus surgical site infections.
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Affiliation(s)
- A Gurtman
- a Pfizer Vaccine Research and Development , Pfizer, Inc ., Pearl River , NY , USA
| | - E Begier
- a Pfizer Vaccine Research and Development , Pfizer, Inc ., Pearl River , NY , USA
| | - N Mohamed
- a Pfizer Vaccine Research and Development , Pfizer, Inc ., Pearl River , NY , USA
| | - J Baber
- b Pfizer Vaccine Research and Development , Sydney , NSW , Australia
| | - C Sabharwal
- a Pfizer Vaccine Research and Development , Pfizer, Inc ., Pearl River , NY , USA
| | - R M Haupt
- c Medical Development, Scientific and Clinical Affairs , Pfizer, Inc ., Collegeville , PA , USA
| | - H Edwards
- d World Wide Regulatory Affairs , Pfizer Inc ., Walton Oaks , UK
| | - D Cooper
- a Pfizer Vaccine Research and Development , Pfizer, Inc ., Pearl River , NY , USA
| | - K U Jansen
- a Pfizer Vaccine Research and Development , Pfizer, Inc ., Pearl River , NY , USA
| | - A S Anderson
- a Pfizer Vaccine Research and Development , Pfizer, Inc ., Pearl River , NY , USA
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18
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Inoue M, Yonemura T, Baber J, Shoji Y, Aizawa M, Cooper D, Eiden J, Gruber WC, Jansen KU, Anderson AS, Gurtman A. Safety, tolerability, and immunogenicity of a novel 4-antigen Staphylococcus aureus vaccine (SA4Ag) in healthy Japanese adults. Hum Vaccin Immunother 2018; 14:2682-2691. [PMID: 30084709 PMCID: PMC6314418 DOI: 10.1080/21645515.2018.1496764] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 06/06/2018] [Accepted: 06/22/2018] [Indexed: 11/29/2022] Open
Abstract
A novel Staphylococcus aureus 4-antigen vaccine (SA4Ag) is under development, comprising capsular polysaccharide serotypes 5 and 8 (CP5 and CP8) conjugated to CRM197, recombinant protein clumping factor A (rmClfA), and recombinant manganese transporter protein C (MntC). We evaluated SA4Ag safety, tolerability, and immunogenicity in Japanese adults aged 20 to 64 and 65 to 85 years. A total of 136 healthy Japanese adults (68 per age group) were randomized 1:1 to receive single-dose SA4Ag or placebo intramuscularly (Day 1). Safety assessments included reactogenicity and adverse events. The ability of the vaccine to induce immune responses that are considered functional due to their ability to facilitate the killing of S. aureus or neutralize S. aureus virulence mechanisms was assessed using 5 different antigen-specific assays. SA4Ag was well tolerated in both age groups, with no safety concerns. At Day 29, > 85% of SA4Ag recipients in each age group achieved predefined thresholds for each antigen. Antibody geometric mean-fold rises from baseline to Day 29 in SA4Ag groups were: > 80 and > 30 for CP5 and CP8 (opsonophagocytic activity assay), > 10 for ClfA (fibrinogen-binding inhibition assay), and > 15 and > 7 for ClfA and MntC (competitive Luminex® immunoassay), respectively. Antibody titers decreased through Month 12 but remained well above baseline and placebo levels. SA4Ag had an acceptable safety profile and induced rapid and robust functional immune responses in both age groups. These results support ongoing development of SA4Ag for the prevention of invasive S. aureus disease in elective-surgery patients in Japan, North America, and Europe.
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Affiliation(s)
| | | | - James Baber
- Pfizer Vaccine Research and Development, Sydney, NSW, Australia
| | - Yasuko Shoji
- Pfizer Vaccine Research and Development, Tokyo, Japan
| | | | - David Cooper
- Pfizer Vaccine Research and Development, Pearl River, NY, USA
| | - Joseph Eiden
- Pfizer Vaccine Research and Development, Pearl River, NY, USA
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19
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Bai J, Wu Y, Zhong K, Xiao K, Liu L, Huang Y, Wang Z, Gao H. A Comparative Study on the Effects of Quinic Acid and Shikimic Acid on Cellular Functions of Staphylococcus aureus. J Food Prot 2018; 81:1187-1192. [PMID: 29939792 DOI: 10.4315/0362-028x.jfp-18-014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Quinic acid (QA) and shikimic acid (SA), two kinds of natural organic acids, have been reported to exhibit potent antibacterial activity against Staphylococcus aureus. In this study, the effects of QA and SA on the cellular functions of S. aureus were investigated by measuring the intracellular pH, intracellular and extracellular ATP concentrations, succinate dehydrogenase activity, DNA content, and interactions between SA and QA with S. aureus DNA. Studies of the cellular functions demonstrated that QA could significantly decrease the intracellular pH, whereas SA had no effect on intracellular pH. QA and SA reduced succinate dehydrogenase activity and caused a significant decrease in intracellular ATP concentration but no proportional increase in extracellular ATP. Moreover, QA and SA both could remarkably reduce the DNA content of S. aureus and directly interact with genomic DNA. The results suggested that the effects of QA and SA on cellular functions were distinguishable, although the chemical structures of these two compounds were similar. In conclusion, the results of the present research suggested that SA and QA could be used as antibacterial agents in food preservation.
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Affiliation(s)
- Jinrong Bai
- 1 Healthy Food Evaluation Research Center and.,2 Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, People's Republic of China (ORCID: http://orcid.org/0000-0002-3657-8993 [J.B.]); and
| | - Yanping Wu
- 1 Healthy Food Evaluation Research Center and.,2 Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, People's Republic of China (ORCID: http://orcid.org/0000-0002-3657-8993 [J.B.]); and
| | - Kai Zhong
- 1 Healthy Food Evaluation Research Center and.,2 Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, People's Republic of China (ORCID: http://orcid.org/0000-0002-3657-8993 [J.B.]); and
| | - Kai Xiao
- 2 Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, People's Republic of China (ORCID: http://orcid.org/0000-0002-3657-8993 [J.B.]); and
| | - Lijin Liu
- 3 Department of Public Health, West China Medical School of Sichuan University, Chengdu 610041, People's Republic of China
| | - Yina Huang
- 3 Department of Public Health, West China Medical School of Sichuan University, Chengdu 610041, People's Republic of China
| | - Zhengshu Wang
- 3 Department of Public Health, West China Medical School of Sichuan University, Chengdu 610041, People's Republic of China
| | - Hong Gao
- 1 Healthy Food Evaluation Research Center and.,2 Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, People's Republic of China (ORCID: http://orcid.org/0000-0002-3657-8993 [J.B.]); and
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20
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Abstract
PURPOSE OF REVIEW Multidrug resistance of bacterial pathogens has confronted physicians around the world with the threat of inefficacy of the antibiotic regime, which is particularly important for patients with sepsis. Antibiotic resistance has revived search for alternative nonantibiotic strategies. Among them, prophylaxis by vaccination is an appealing concept. RECENT FINDINGS This review provides a compact overview on available vaccines against community-acquired pathogens such as pneumococci (in synergy with influenza) and meningococci and provides an overview on the ongoing developments of vaccines targeting typical nosocomial pathogens such as Clostridium difficile, Staphylococcus aureus, Acintetobacter baumannii, Klebsiella pneumonia, and Pseudomonas aeruginosa. SUMMARY The effects achieved by some conjugated vaccines (e.g. against Haemophilus influenzae B and Streptococcus pneumoniae) are encouraging. Their widespread use has resulted in a decrease or almost elimination of invasive diseases by the covered pneumococcal serotypes or Haemophilus influenzae B, respectively. These vaccines confer not only individual protection but also exploit herd protection effects. However, a multitude of failures reflects the obstacles on the way to effective and well tolerated bacterial vaccines. Regional differences in strain prevalence and variability of antigens that limit cross-protectivity remain major obstacles. However, promising candidates are in clinical development.
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21
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Wu Y, Bai J, Liu X, Liu L, Zhong K, Huang Y, Gao H. Antibacterial effect of 3-p-trans-coumaroyl-2-hydroxyquinic acid, a phenolic compound from needles ofCedrus deodara, on cellular functions ofStaphylococcus aureus. RSC Adv 2018; 8:4969-4975. [PMID: 35539522 PMCID: PMC9077780 DOI: 10.1039/c7ra13457f] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 01/22/2018] [Indexed: 11/21/2022] Open
Abstract
Structure–activity relationship of 3-p-trans-coumaroyl-2-hydroxyquinic acid, a phenolic compound from needles ofCedrus deodara, againstStaphylococcus aureusand its effect on the cellular functions.
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Affiliation(s)
- Yanping Wu
- Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- China
- Department of Food Science and Technology
| | - Jinrong Bai
- Department of Food Science and Technology
- College of Light Industry, Textile and Food Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Xiaoyan Liu
- Department of Food Science and Technology
- College of Light Industry, Textile and Food Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Lijin Liu
- Department of Public Health
- West China Medical School
- Sichuan University
- Chengdu 610041
- China
| | - Kai Zhong
- Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- China
- Department of Food Science and Technology
| | - Yina Huang
- Department of Public Health
- West China Medical School
- Sichuan University
- Chengdu 610041
- China
| | - Hong Gao
- Healthy Food Evaluation Research Center
- Sichuan University
- Chengdu 610065
- China
- Department of Food Science and Technology
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22
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Xu X, Zhu H, Lv H. Safety of Staphylococcus aureus four-antigen and three-antigen vaccines in healthy adults: A meta-analysis of randomized controlled trials. Hum Vaccin Immunother 2017; 14:314-321. [PMID: 29064736 DOI: 10.1080/21645515.2017.1395540] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
PURPOSE Two new Staphylococcus aureus vaccines, S. aureus four-antigen (SA4Ag) and three-antigen (SA3Ag) vaccines, have good immunogenicity and tolerance. However, the safety of these vaccines is worth exploring. Here, we performed a meta-analysis to investigate the safety of SA3Ag and SA4Ag by evaluating systemic and local adverse events. METHODS The Medline, EMBASE, and Cochrane databases were searched for randomized clinical trials confirming the safety of SA4Ag and SA3Ag. Two investigators independently selected suitable trials, assessed trial quality, and extracted data. RESULTS Three studies comprising a total of 1,148 participants were included in this review. The two S. aureus vaccines did not increase systemic adverse events (relative ratio 1.1 [95% confidence interval 0.98, 1.24]), but increased the incidence of local adverse events (2.89 [2.15, 3.90]). However, the incidence of severe local adverse events (4.06 [0.78, 21.24]) did not rise significantly. CONCLUSIONS SA4Ag and SA3Ag have acceptable safety in adults.
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Affiliation(s)
- Xiaoqun Xu
- a Department of Clinical Laboratory, Centre of Laboratory Medicine , Zhejiang Provincial People's Hospital, The Affiliated People's Hospital of Hangzhou Medical College , Hangzhou , Zhejiang , China.,b Zhejiang Chinese Medical University , Hangzhou , Zhejiang , China
| | - Houyong Zhu
- c Department of Cardiology , Hangzhou Hospital of Traditional Chinese Medicine; Hangzhou Dingqiao Hospital , Hangzhou , Zhejiang , China
| | - Huoyang Lv
- a Department of Clinical Laboratory, Centre of Laboratory Medicine , Zhejiang Provincial People's Hospital, The Affiliated People's Hospital of Hangzhou Medical College , Hangzhou , Zhejiang , China
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23
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Bai J, Wu Y, Wang X, Liu X, Zhong K, Huang Y, Chen Y, Gao H. In vitro
and
in vivo
characterization of the antibacterial activity and membrane damage mechanism of quinic acid against
Staphylococcus aureus. J Food Saf 2017. [DOI: 10.1111/jfs.12416] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jinrong Bai
- Department of Food Science and Technology, College of Light Industry, Textile and Food EngineeringSichuan UniversityChengdu China
| | - Yanping Wu
- Department of Food Science and Technology, College of Light Industry, Textile and Food EngineeringSichuan UniversityChengdu China
| | - Xiaoyan Wang
- Department of Food Science and Technology, College of Light Industry, Textile and Food EngineeringSichuan UniversityChengdu China
| | - Xiaoyan Liu
- Department of Food Science and Technology, College of Light Industry, Textile and Food EngineeringSichuan UniversityChengdu China
| | - Kai Zhong
- Department of Food Science and Technology, College of Light Industry, Textile and Food EngineeringSichuan UniversityChengdu China
| | - Yina Huang
- Department of Public HealthWest China Medical School, Sichuan UniversityChengdu China
| | - Yiting Chen
- International Department of Shude High SchoolChengdu China
| | - Hong Gao
- Department of Food Science and Technology, College of Light Industry, Textile and Food EngineeringSichuan UniversityChengdu China
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24
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Fluorimetric sandwich affinity assay for Staphylococcus aureus based on dual-peptide recognition on magnetic nanoparticles. Mikrochim Acta 2017. [DOI: 10.1007/s00604-017-2396-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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25
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Hepburn L, Hijnen D, Sellman B, Mustelin T, Sleeman M, May R, Strickland I. The complex biology and contribution of Staphylococcus aureus
in atopic dermatitis, current and future therapies. Br J Dermatol 2017; 177:63-71. [DOI: 10.1111/bjd.15139] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2016] [Indexed: 12/22/2022]
Affiliation(s)
- L. Hepburn
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
| | - D.J. Hijnen
- University Medical Center Utrecht; Department of Dermatology; Utrecht the Netherlands
| | | | | | - M.A. Sleeman
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
| | - R.D. May
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
| | - I. Strickland
- MedImmune; Milstein Building; Granta Park; Cambridge CB21 6GH U.K
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Reddy PN, Srirama K, Dirisala VR. An Update on Clinical Burden, Diagnostic Tools, and Therapeutic Options of Staphylococcus aureus. Infect Dis (Lond) 2017; 10:1179916117703999. [PMID: 28579798 PMCID: PMC5443039 DOI: 10.1177/1179916117703999] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 03/18/2017] [Indexed: 12/26/2022] Open
Abstract
Staphylococcus aureus is an important pathogen responsible for a variety of diseases ranging from mild skin and soft tissue infections, food poisoning to highly serious diseases such as osteomyelitis, endocarditis, and toxic shock syndrome. Proper diagnosis of pathogen and virulence factors is important for providing timely intervention in the therapy. Owing to the invasive nature of infections and the limited treatment options due to rampant spread of antibiotic-resistant strains, the trend for development of vaccines and antibody therapy is increasing at rapid rate than development of new antibiotics. In this article, we have discussed elaborately about the host-pathogen interactions, clinical burden due to S aureus infections, status of diagnostic tools, and treatment options in terms of prophylaxis and therapy.
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Mohamed N, Wang MY, Le Huec JC, Liljenqvist U, Scully IL, Baber J, Begier E, Jansen KU, Gurtman A, Anderson AS. Vaccine development to prevent Staphylococcus aureus surgical-site infections. Br J Surg 2017; 104:e41-e54. [PMID: 28121039 DOI: 10.1002/bjs.10454] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/27/2016] [Accepted: 11/06/2016] [Indexed: 12/12/2022]
Abstract
BACKGROUND Staphylococcus aureus surgical-site infections (SSIs) are a major cause of poor health outcomes, including mortality, across surgical specialties. Despite current advances as a result of preventive interventions, the disease burden of S. aureus SSI remains high, and increasing antibiotic resistance continues to be a concern. Prophylactic S. aureus vaccines may represent an opportunity to prevent SSI. METHODS A review of SSI pathophysiology was undertaken in the context of evaluating new approaches to developing a prophylactic vaccine to prevent S. aureus SSI. RESULTS A prophylactic vaccine ideally would provide protective immunity at the time of the surgical incision to prevent initiation and progression of infection. Although the pathogenicity of S. aureus is attributed to many virulence factors, previous attempts to develop S. aureus vaccines targeted only a single virulence mechanism. The field has now moved towards multiple-antigen vaccine strategies, and promising results have been observed in early-phase clinical studies that supported the recent initiation of an efficacy trial to prevent SSI. CONCLUSION There is an unmet medical need for novel S. aureus SSI prevention measures. Advances in understanding of S. aureus SSI pathophysiology could lead to the development of effective and safe prophylactic multiple-antigen vaccines to prevent S. aureus SSI.
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Affiliation(s)
- N Mohamed
- Pfizer Vaccine Research and Development, Pearl River, New York, USA
| | - M Y Wang
- Departments of Neurological Surgery and Rehabilitation Medicine, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - J-C Le Huec
- Spine Unit 2, Surgical Research Laboratory, Bordeaux University Hospital, Bordeaux, France
| | - U Liljenqvist
- Department of Spine Surgery, St Franziskus Hospital Muenster, Münster, Germany
| | - I L Scully
- Pfizer Vaccine Research and Development, Pearl River, New York, USA
| | - J Baber
- Pfizer Vaccine Clinical Research and Development, Sydney, New South Wales, Australia
| | - E Begier
- Pfizer Vaccine Clinical Research and Development, Pearl River, New York, USA
| | - K U Jansen
- Pfizer Vaccine Research and Development, Pearl River, New York, USA
| | - A Gurtman
- Pfizer Vaccine Clinical Research and Development, Pearl River, New York, USA
| | - A S Anderson
- Pfizer Vaccine Research and Development, Pearl River, New York, USA
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Begier E, Seiden DJ, Patton M, Zito E, Severs J, Cooper D, Eiden J, Gruber WC, Jansen KU, Anderson AS, Gurtman A. SA4Ag, a 4-antigen Staphylococcus aureus vaccine, rapidly induces high levels of bacteria-killing antibodies. Vaccine 2017; 35:1132-1139. [PMID: 28143674 DOI: 10.1016/j.vaccine.2017.01.024] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 12/12/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
BACKGROUND Staphylococcus aureus is a leading cause of healthcare-associated infections. No preventive vaccine is currently licensed. SA4Ag is an investigational 4-antigen S. aureus vaccine, composed of capsular polysaccharide conjugates of serotypes 5 and 8 (CP5 and CP8), recombinant surface protein clumping factor A (rmClfA), and recombinant manganese transporter protein C (rMntC). This Phase 1 study aimed to confirm the safety and immunogenicity of SA4Ag produced by the final manufacturing process before efficacy study initiation in a surgical population. METHODS Healthy adults (18-<65years) received one intramuscular SA4Ag injection. Serum functional antibodies were measured at baseline and Day 29 post-vaccination. An opsonophagocytic activity (OPA) assay measured the ability of vaccine-induced antibodies to CP5 and CP8 to kill S. aureus clinical isolates. For MntC and ClfA, antigen-specific immunogenicity was assessed via competitive Luminex® immunoassay (cLIA) and via fibrinogen-binding inhibition (FBI) assay for ClfA only. Reactogenicity and adverse event data were collected. RESULTS One hundred participants were vaccinated. SA4Ag was well tolerated, with a satisfactory safety profile. On Day 29, OPA geometric mean titers (GMTs) were 45,738 (CP5, 95% CI: 38,078-54,940) and 42,652 (CP8, 95% CI: 32,792-55,477), consistent with 69.2- and 28.9-fold rises in bacteria-killing antibodies, respectively; cLIA GMTs were 2064.4 (MntC, 95% CI: 1518.2-2807.0) and 3081.4 (ClfA, 95% CI: 2422.2-3920.0), consistent with 19.6- and 12.3-fold rises, respectively. Similar to cLIA results, ClfA FBI titers rose 11.0-fold (GMT: 672.2, 95% CI: 499.8-904.2). The vast majority of participants achieved the pre-defined biologically relevant thresholds: CP5: 100%; CP8: 97.9%, ClfA: 87.8%; and MntC 96.9%. CONCLUSIONS SA4Ag was safe, well tolerated, and rapidly induced high levels of bacteria-killing antibodies in healthy adults. A Phase 2B efficacy trial in adults (18-85years) undergoing elective spinal fusion is ongoing to assess SA4Ag's ability to prevent postoperative invasive surgical site and bloodstream infections caused by S. aureus. Clinicaltrials.gov Identifier: NCT02364596.
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Affiliation(s)
- Elizabeth Begier
- Pfizer Vaccine Clinical Research & Development, Pearl River, NY, USA.
| | | | - Michael Patton
- Pfizer Vaccine Clinical Research & Development, Maidenhead, UK
| | | | - Joseph Severs
- Pfizer Vaccine Clinical Research & Development, Pearl River, NY, USA
| | - David Cooper
- Vaccine Research & Development, Pearl River, NY, USA
| | - Joseph Eiden
- Pfizer Vaccine Clinical Research & Development, Pearl River, NY, USA
| | - William C Gruber
- Pfizer Vaccine Clinical Research & Development, Pearl River, NY, USA
| | | | | | - Alejandra Gurtman
- Pfizer Vaccine Clinical Research & Development, Pearl River, NY, USA
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Safety, tolerability, and immunogenicity of a 4-antigen Staphylococcus aureus vaccine (SA4Ag): Results from a first-in-human randomised, placebo-controlled phase 1/2 study. Vaccine 2016; 35:375-384. [PMID: 27916408 DOI: 10.1016/j.vaccine.2016.11.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 11/01/2016] [Accepted: 11/02/2016] [Indexed: 11/21/2022]
Abstract
BACKGROUND A prophylactic Staphylococcus aureus four-antigen vaccine (SA4Ag) is under development for prevention of invasive S. aureus disease. A preliminary S. aureus three-antigen vaccine (SA3Ag) was reformulated to include a novel manganese transporter protein (MntC or rP305A). This study describes the first-in-human dose-finding, safety, and immunogenicity results for SA4Ag. METHODS In this double-blind, sponsor-unblind, placebo-controlled, phase 1/2 study, 454 healthy adults aged 18-64years were randomised to receive a single dose of one of three formulations of SA4Ag with escalating dose levels of rP305A or placebo. Functional immune responses were measured using opsonophagocytic activity (OPA) killing and fibrinogen-binding inhibition (FBI) assays; antigen-specific immunogenicity was assessed using a four-plex competitive Luminex® immunoassay (cLIA). RESULTS A high proportion of SA4Ag recipients met the pre-defined antibody thresholds for each antigen at Day 29. A substantial and dose-level dependent immune response was observed for rP305A, with up to 18-fold rises in cLIA titres at Day 29. Robust functional responses were demonstrated, with >80-fold and >20-fold rises in OPA assay titres at Day 29 using S. aureus strains expressing capsular polysaccharide serotypes 5 and 8, respectively. Durable antibody responses were observed through month 12, gradually waning from peak levels achieved by days 11-15. SA4Ag was well tolerated, and no vaccine-related serious adverse events were reported. CONCLUSIONS Single-dose vaccination of SA4Ag in healthy adults aged 18-64years safely induced rapid and robust functional immune responses that were durable through month 12, supporting further development of this vaccine. TRIAL REGISTRATION NUMBER NCT01364571.
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Safety, tolerability, and immunogenicity of a single dose 4-antigen or 3-antigen Staphylococcus aureus vaccine in healthy older adults: Results of a randomised trial. Vaccine 2016; 35:385-394. [PMID: 27866765 DOI: 10.1016/j.vaccine.2016.11.032] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 11/01/2016] [Accepted: 11/07/2016] [Indexed: 12/23/2022]
Abstract
BACKGROUND The decline in immune function with age is a challenge to vaccine development. Following an initial study in adults aged 18-64years, this study evaluated the safety and immunogenicity of Staphylococcus aureus (S. aureus) 4-antigen (SA4Ag) and 3-antigen (SA3Ag) vaccine in older adults. SA3Ag included capsular polysaccharide serotypes 5 and 8 (CP5 and CP8) conjugated to the nontoxic mutant form of diphtheria toxin (CRM197) and a recombinant version of clumping factor A (ClfA). SA4Ag included these antigens, with the addition of a recombinant manganese transporter C (rP305A or MntC). Both vaccines were unadjuvanted. METHODS In this double-blind, sponsor-unblinded, placebo-controlled, phase 1/2 study, 284 healthy adults (aged 65-85years) were randomised to receive a single dose of one of three formulations of SA4Ag with escalating dose levels of rP305A, SA3Ag, or placebo. Functional immune responses were measured using opsonophagocytic activity (OPA) killing and fibrinogen-binding inhibition (FBI) assays; immunogenicity was also assessed using a competitive Luminex® immunoassay (cLIA). T-cell responses were measured in a small subgroup of subjects using intracellular cytokine staining (ICS) assays. RESULTS The results demonstrated rapid and robust functional immune responses to all antigens in healthy older adults. A high proportion of active vaccine recipients met the pre-defined antibody thresholds for each antigen at Day 29. SA4Ag elicited a dose-level response to rP305A with up to a 13-fold rise in cLIA titres at Day 29. Opsonophagocytic activity (OPA) assays showed >50- and >20-fold rises in functional titres using S. aureus strains expressing CP5 and CP8, respectively, at Day 29. T-cell cytokine responses were not substantially above background levels. There were no safety concerns in this study population and no increases in adverse events with higher rP305A dose levels. CONCLUSIONS Single-dose vaccination of SA4Ag and SA3Ag in healthy adults aged 65-85years safely induced rapid and robust functional immune responses, supporting further development of SA4Ag for the prevention of S. aureus disease in adults up to age 85years. TRIAL REGISTRATION NUMBER NCT01643941.
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Is it true that plant-derived polyphenols are always beneficial for the human? In vitro study on Leonurus cardiaca extract properties in the context of the pathogenesis of Staphylococcus aureus infections. J Med Microbiol 2016; 65:1171-1181. [DOI: 10.1099/jmm.0.000332] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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High Resolution Mapping of Bactericidal Monoclonal Antibody Binding Epitopes on Staphylococcus aureus Antigen MntC. PLoS Pathog 2016; 12:e1005908. [PMID: 27689696 PMCID: PMC5045189 DOI: 10.1371/journal.ppat.1005908] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 08/30/2016] [Indexed: 11/19/2022] Open
Abstract
The Staphylococcus aureus manganese transporter protein MntC is under investigation as a component of a prophylactic S.aureus vaccine. Passive immunization with monoclonal antibodies mAB 305-78-7 and mAB 305-101-8 produced using MntC was shown to significantly reduce S. aureus burden in an infant rat model of infection. Earlier interference mapping suggested that a total of 23 monoclonal antibodies generated against MntC could be subdivided into three interference groups, representing three independent immunogenic regions. In the current work binding epitopes for selected representatives of each of these interference groups (mAB 305-72-5 – group 1, mAB 305-78-7 – group 2, and mAB 305-101-8 – group 3) were mapped using Hydrogen-Deuterium Exchange Mass Spectrometry (DXMS). All of the identified epitopes are discontinuous, with binding surface formed by structural elements that are separated within the primary sequence of the protein but adjacent in the context of the three-dimensional structure. The approach was validated by co-crystallizing the Fab fragment of one of the antibodies (mAB 305-78-7) with MntC and solving the three-dimensional structure of the complex. X-ray results themselves and localization of the mAB 305-78-7 epitope were further validated using antibody binding experiments with MntC variants containing substitutions of key amino acid residues. These results provided insight into the antigenic properties of MntC and how these properties may play a role in protecting the hostagainst S. aureus infection by preventing the capture and transport of Mn2+, a key element that the pathogen uses to evade host immunity. Staphylococcus aureus protein MntC is a metal-binding protein of the ABC-type transporter involved in the acquisition of an essential nutrient, Mn2+, by the pathogen. An earlier study demonstrated that use of MntC as an antigen in experimental vaccine can provide protection against staphylococcal infections in animals and identified three groups of protective monoclonal antibodies induced by the protein. In the current work we employed Deuterium-Hydrogen Exchange Mass Spectrometry (DXMS) to determine binding sites of selected representatives from each of those three groups. DXMS results were further validated using X-ray crystallography, site-directed mutagenesis and functional studies. Locations of the binding sites and results of the functional studies were used to draw conclusion on molecular mechanisms of protection afforded by MntC: antibodies belonging to two of the groups are predicted to interfere with Mn2+ transfer from the protein to the transmembrane channel pore, while the third group of the antibodies is expected to interfere with Mn2+ binding to MntC itself. The net result in both cases is impaired Mn2+ transport across the bacterial membrane and increased susceptibility of the bacterium to the oxidative stress, likely due to the reduced activity of superoxide dismutase which requires Mn2+ as an essential co-factor for activity.
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Antibacterial Activity and Membrane-Disruptive Mechanism of 3-p-trans-Coumaroyl-2-hydroxyquinic Acid, a Novel Phenolic Compound from Pine Needles of Cedrus deodara, against Staphylococcus aureus. Molecules 2016; 21:molecules21081084. [PMID: 27548123 PMCID: PMC6273998 DOI: 10.3390/molecules21081084] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 08/12/2016] [Accepted: 08/15/2016] [Indexed: 12/22/2022] Open
Abstract
Recently, we reported that a novel phenolic compound isolated from Cedrus deodara, 3-p-trans-coumaroyl-2-hydroxyquinic acid (CHQA), exhibits a potent antioxidant activity. The present study aimed to evaluate the antibacterial activity of CHQA against eleven food-borne pathogens and to elucidate its mechanism of action against Staphylococcus aureus. The results from minimum inhibitory concentration (MIC) determinations showed that CHQA exhibited moderate inhibitory effects on all of the tested pathogens with MIC values ranging from 2.5-10 mg/mL. Membrane potential measurements and flow cytometric analysis demonstrated that CHQA damaged the cytoplasmic membrane of S. aureus, causing a significant membrane hyperpolarization with a loss of membrane integrity. Moreover, CHQA induced an increase in membrane fluidity and conformational changes in membrane protein of S. aureus, suggesting that CHQA probably acts on the cell membrane by interactions with membrane lipid and protein. Transmission electron microscopic observations further confirmed that CHQA disrupted the cell membrane of S. aureus and caused severe morphological changes, which even led to leakage of intracellular constituents. These findings indicated that CHQA could have the potential to serve as a natural antibacterial agent to control and prevent the growth of pathogens in food and in food-processing environments.
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Khatib R, Sharma M, Johnson LB, Riederer K, Briski L. Polymicrobial Staphylococcus aureus bacteremia: Frequency, distinguishing characteristics and outcome. Diagn Microbiol Infect Dis 2016; 86:311-315. [PMID: 27575461 DOI: 10.1016/j.diagmicrobio.2016.08.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/01/2016] [Accepted: 08/10/2016] [Indexed: 11/19/2022]
Abstract
Staphylococcus aureus bacteremia (SAB) is usually monomicrobial (M-SAB). We reviewed SAB in adults (≥18years old) over a 13year-period and compared polymicrobial (P-SAB) and M-SAB. We encountered 93 P-SAB among 1537 SAB cases (6.1%). The source distribution was comparable; however, source-specified differences were apparent. P-SAB was noted in 12/58 (20.7%) necrotizing soft tissue infections/sacral decubiti and foot gangrene vs. 1/122 (0.8%) cellulitis/abscesses (P<0.001), in 7/64 (10.9%) femoral intravascular catheters (IVC) vs.16/376 (4.3%) IVC in other sites (P=0.03) and 15/134 (11.2%) healthcare-associated pneumonia (HAP) vs. 1/33 (3.0%) community-associated cases (P=0.1). Methicillin-resistance frequency was similar but community-associated SCCmec types (IV/V) were infrequent (17.9% vs. 34.2%; P=0.04). P-SAB was associated with higher mortality (50.5% vs. 24.2%; P<0.001) across nearly all sources. In summary, P-SAB is infrequent, usually encountered in necrotizing soft tissue infections/decubiti, femoral IVC and possibly HAP. The actual incidence of S. aureus in these infections should be defined.
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Affiliation(s)
- Riad Khatib
- Department of Medicine, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA.
| | - Mamta Sharma
- Department of Medicine, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA
| | - Leonard B Johnson
- Department of Medicine, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA
| | - Kathleen Riederer
- Department of Medical Education, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA
| | - Laurence Briski
- Department of Pathology, St John Hospital & Medical Center, Grosse Pointe Woods, MI, USA
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Safety and immunogenicity of a booster dose of a 3-antigen Staphylococcus aureus vaccine (SA3Ag) in healthy adults: A randomized phase 1 study. J Infect 2016; 73:437-454. [PMID: 27519620 DOI: 10.1016/j.jinf.2016.08.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/29/2016] [Accepted: 08/05/2016] [Indexed: 12/28/2022]
Abstract
OBJECTIVE A 2-stage, phase 1, randomized, placebo-controlled study in healthy adults to assess immunogenicity and safety of a booster dose at three dose levels of a 3-antigen Staphylococcus aureus vaccine (SA3Ag) containing recombinant clumping factor A (ClfA) and capsular polysaccharides 5 and 8 (CP5 and CP8) conjugated to a diphtheria toxoid. METHODS Six months after initial single vaccination, in Stage 2, SA3Ag recipients were randomized (1:1) to booster vaccination or placebo, while Stage 1 placebo recipients received placebo again. Pre- and post-vaccination blood samples were analyzed. RESULTS In Stage 2 (n = 345), pre-booster CP5 and CP8 titers remained high with no increase post-booster. ClfA titers remained high after initial vaccination and increased post-booster, approaching the peak response to the initial dose. Post-booster local reactions were more frequent and of greater severity than reported after the initial vaccination, particularly for the high-dose level recipients. Post hoc analysis showed no dose-response pattern and no obvious association between diphtheria toxoid titers and local reactions after initial or booster vaccination. CONCLUSION Immune responses after the initial vaccination persisted for the 12 months studied, with little additional response after the booster dose at 6 months. Post-booster injection site reactions were more frequent and more severe but self-limiting. CLINICALTRIALS. GOV IDENTIFIER NCT01018641.
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36
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Wu Y, Bai J, Zhong K, Huang Y, Gao H. A dual antibacterial mechanism involved in membrane disruption and DNA binding of 2R,3R-dihydromyricetin from pine needles of Cedrus deodara against Staphylococcus aureus. Food Chem 2016; 218:463-470. [PMID: 27719936 DOI: 10.1016/j.foodchem.2016.07.090] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 06/09/2016] [Accepted: 07/12/2016] [Indexed: 01/01/2023]
Abstract
The antibacterial activity and mechanism of 2R,3R-dihydromyricetin (DMY) against Staphylococcus aureus were investigated. The minimum inhibitory concentration of DMY against S. aureus was 0.125mg/ml, and the growth inhibitory assay also revealed that DMY showed a potent antibacterial activity against S. aureus. Massive nucleotide leakage and flow cytometric analysis demonstrated that DMY disrupted the membrane integrity of S. aureus. Morphological changes and membrane hyperpolarization of S. aureus cells treated with DMY further suggested that DMY destroyed cell membrane. Meanwhile, DMY probably interacted with membrane lipids and proteins, causing a significant reduction in membrane fluidity and changes in conformation of membrane protein. Moreover, DMY could interact with S. aureus DNA through the groove binding mode. Overall, the results suggested that DMY could be applied as a candidate for the development of new food preservatives as it achieved bactericidal activity by damaging cell membrane and binding to intracellular DNA.
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Affiliation(s)
- Yanping Wu
- Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China
| | - Jinrong Bai
- Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China
| | - Kai Zhong
- Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China
| | - Yina Huang
- Department of Public Health, West China Medical School, Sichuan University, Chengdu 610041, China.
| | - Hong Gao
- Department of Food Science and Technology, College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu 610065, China.
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Dayan GH, Mohamed N, Scully IL, Cooper D, Begier E, Eiden J, Jansen KU, Gurtman A, Anderson AS. Staphylococcus aureus: the current state of disease, pathophysiology and strategies for prevention. Expert Rev Vaccines 2016; 15:1373-1392. [PMID: 27118628 DOI: 10.1080/14760584.2016.1179583] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Staphylococcus aureus is both a commensal organism and also an important opportunistic human pathogen, causing a variety of community and hospital-associated pathologies, such as bacteremia-sepsis, endocarditis, pneumonia, osteomyelitis, arthritis and skin diseases. The resurgence of S. aureus during the last decade in many settings has been facilitated not only by bacterial antibiotic resistance mechanisms but also by the emergence of new S. aureus clonal types with increased expression of virulence factors and the capacity to neutralize the host immune response. Prevention of the spread of S. aureus infection relies on the use of contact precautions and adequate procedures for infection control that so far have not been fully effective. Prevention using a prophylactic vaccine would complement these processes, having the potential to bring additional, significant progress toward decreasing invasive disease due to S. aureus.
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Affiliation(s)
- Gustavo H Dayan
- a Pfizer Vaccine Research and Development , Pearl River , NY , USA
| | - Naglaa Mohamed
- a Pfizer Vaccine Research and Development , Pearl River , NY , USA
| | - Ingrid L Scully
- a Pfizer Vaccine Research and Development , Pearl River , NY , USA
| | - David Cooper
- a Pfizer Vaccine Research and Development , Pearl River , NY , USA
| | - Elizabeth Begier
- a Pfizer Vaccine Research and Development , Pearl River , NY , USA
| | - Joseph Eiden
- a Pfizer Vaccine Research and Development , Pearl River , NY , USA
| | - Kathrin U Jansen
- a Pfizer Vaccine Research and Development , Pearl River , NY , USA
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Yang HJ, Zhang JY, Wei C, Yang LY, Zuo QF, Zhuang Y, Feng YJ, Srinivas S, Zeng H, Zou QM. Immunisation With Immunodominant Linear B Cell Epitopes Vaccine of Manganese Transport Protein C Confers Protection against Staphylococcus aureus Infection. PLoS One 2016; 11:e0149638. [PMID: 26895191 PMCID: PMC4764517 DOI: 10.1371/journal.pone.0149638] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 02/03/2016] [Indexed: 12/15/2022] Open
Abstract
Vaccination strategies for Staphylococcus aureus, particularly methicillin-resistant S. aureus (MRSA) infections have attracted much research attention. Recent efforts have been made to select manganese transport protein C, or manganese binding surface lipoprotein C (MntC), which is a metal ion associated with pathogen nutrition uptake, as potential candidates for an S. aureus vaccine. Although protective humoral immune responses to MntC are well-characterised, much less is known about detailed MntC-specific B cell epitope mapping and particularly epitope vaccines, which are less-time consuming and more convenient. In this study, we generated a recombinant protein rMntC which induced strong antibody response when used for immunisation with CFA/IFA adjuvant. On the basis of the results, linear B cell epitopes within MntC were finely mapped using a series of overlapping synthetic peptides. Further studies indicate that MntC113-136, MntC209-232, and MntC263-286 might be the original linear B-cell immune dominant epitope of MntC, furthermore, three-dimensional (3-d) crystal structure results indicate that the three immunodominant epitopes were displayed on the surface of the MntC antigen. On the basis of immunodominant MntC113-136, MntC209-232, and MntC263-286 peptides, the epitope vaccine for S. aureus induces a high antibody level which is biased to TH2 and provides effective immune protection and strong opsonophagocytic killing activity in vitro against MRSA infection. In summary, the study provides strong proof of the optimisation of MRSA B cell epitope vaccine designs and their use, which was based on the MntC antigen in the development of an MRSA vaccine.
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Affiliation(s)
- Hui-Jie Yang
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
| | - Jin-Yong Zhang
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
| | - Chao Wei
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
| | - Liu-Yang Yang
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
| | - Qian-Fei Zuo
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
| | - Yuan Zhuang
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
| | - You-Jun Feng
- School of Basic Medical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, PR China
| | - Swaminath Srinivas
- Department of Biochemistry, University of Illinois, Urbana, IL, 61801, United States of America
| | - Hao Zeng
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
- * E-mail: (HZ); (QMZ)
| | - Quan-Ming Zou
- National Engineering Research Centre for Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing 400038, PR China
- * E-mail: (HZ); (QMZ)
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Antibacterial Activity of Shikimic Acid from Pine Needles of Cedrus deodara against Staphylococcus aureus through Damage to Cell Membrane. Int J Mol Sci 2015; 16:27145-55. [PMID: 26580596 PMCID: PMC4661873 DOI: 10.3390/ijms161126015] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 10/19/2015] [Accepted: 11/03/2015] [Indexed: 12/13/2022] Open
Abstract
Shikimic acid (SA) has been reported to possess antibacterial activity against Staphylococcus aureus, whereas the mode of action of SA is still elusive. In this study, the antibacterial activity and mechanism of SA toward S. aureus by cell membrane damage was investigated. After SA treatment, massive K+ and nucleotide leakage from S. aureus, and a significant change in the membrane potential was observed, suggesting SA may act on the membrane by destroying the cell membrane permeability. Through transmission electron microscopic observations we further confirmed that SA can disrupt the cell membrane and membrane integrity. Meanwhile, SA was found to be capable of reducing the membrane fluidity of the S. aureus cell. Moreover, the fluorescence experiments indicated that SA could quench fluorescence of Phe residues of the membrane proteins, thus demonstrating that SA can bind to S. aureus membrane proteins. Therefore, these results showed the antibacterial activity of SA against S. aureus could be caused by the interactions of SA with S. aureus membrane proteins and lipids, resulting in causing cell membrane dysfunction and bacterial damage or even death. This study reveals the potential use of SA as an antibacterial agent.
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Nissen M, Marshall H, Richmond P, Shakib S, Jiang Q, Cooper D, Rill D, Baber J, Eiden J, Gruber W, Jansen KU, Emini EA, Anderson AS, Zito ET, Girgenti D. A randomized phase I study of the safety and immunogenicity of three ascending dose levels of a 3-antigen Staphylococcus aureus vaccine (SA3Ag) in healthy adults. Vaccine 2015; 33:1846-54. [PMID: 25707693 DOI: 10.1016/j.vaccine.2015.02.024] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 02/10/2015] [Accepted: 02/10/2015] [Indexed: 10/24/2022]
Abstract
BACKGROUND Staphylococcus aureus is a common cause of healthcare-acquired morbidity and mortality and increased healthcare resource utilization. A prophylactic vaccine is being developed that may reduce this disease burden. METHODS Volunteers in good general health aged 50-85 (n=312) and 18-24 (n=96) years were randomized to receive a single intramuscular dose of one of three dose levels of a non-adjuvanted, 3-antigen S. aureus vaccine (SA3Ag) or placebo. SA3Ag antigens included capsular polysaccharides 5 and 8 (CP5 and CP8), each conjugated to cross-reactive material 197 (CRM197), and recombinant clumping factor A (ClfA). Safety, tolerability, and immunogenicity were evaluated. RESULTS At day 29 post-vaccination, robust immune responses were observed in both age cohorts at all three SA3Ag dose levels. In the primary analysis population, the 50- to 85-year age stratum, geometric mean-fold-rises in competitive Luminex(®) immunoassay antibody titers from baseline ranged from 29.2 to 83.7 (CP5), 14.1 to 31.0 (CP8), and 37.1 to 42.9 (ClfA), all (P<0.001) exceeding the pre-defined two-fold rise criteria. Similar rises in opsonophagocytic activity assay titers demonstrated functionality of the immune response. Most injection-site reactions were mild in severity and there were no substantial differences (SA3Ag vs. placebo) with regard to systemic or adverse events. CONCLUSIONS In this study of healthy adults aged 50-85 and 18-24 years, SA3Ag elicited a rapid and robust immune response and was well tolerated, with no notable safety concerns.
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Affiliation(s)
- Michael Nissen
- Queensland Paediatric Infectious Diseases Clinical Trials Centre, Royal Children's Hospital and Children's Health Queensland, Brisbane, QLD, Australia.
| | - Helen Marshall
- Vaccinology and Immunology Research Trials Unit, Women's and Children's Hospital and Robinson Research Institute and School of Paediatrics and Reproductive Health, University of Adelaide, Adelaide, SA, Australia.
| | - Peter Richmond
- University of Western Australia School of Paediatrics and Child Health & Telethon Kids Institute, Perth, WA, Australia
| | | | | | | | | | - James Baber
- Pfizer Australia Pty Ltd, Sydney, NSW, Australia
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