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Shi X, Ni H, Tang L, Li M, Wu Y, Xu Y. Comprehensive Gene Analysis Reveals Cuproptosis-Related Gene Signature Associated with M2 Macrophage in Staphylococcus aureus-Infected Osteomyelitis. J Inflamm Res 2024; 17:3057-3077. [PMID: 38770176 PMCID: PMC11104443 DOI: 10.2147/jir.s457414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 05/08/2024] [Indexed: 05/22/2024] Open
Abstract
Objective Osteomyelitis is a challenging disease in the field of bone infections, with its immune and molecular regulatory mechanisms still poorly understood. The aim of this study is to explore the value and potential mechanisms of cuproptosis-related genes (CRGs) in Staphylococcus aureus (S. aureus)-infected osteomyelitis from an immunological perspective. Methods Initially, three transcriptomic datasets from public databases were integrated and analyzed, and consistent expression of CRGs in S. aureus-infected osteomyelitis was identified. Subsequently, immune infiltration analysis was performed, and M2 macrophage-related CRGs (M2R-CRGs) were further identified. Their potential molecular mechanisms were evaluated using Gene Set Variation Analysis (GSVA) and Gene Set Enrichment Analysis (GSEA). Finally, distinct osteomyelitis subtypes and diagnostic models based on characteristic M2R-CRGs were constructed. Results Through correlation analysis with immune cell infiltration, three characteristic M2R-CRGs (SLC31A1, DLD, and MTF1) were identified. Further analysis using unsupervised clustering and immune microenvironment analysis indicated that cluster 1 might activate pro-inflammatory responses, while cluster 2 was shown to exhibit anti-inflammatory effects in osteomyelitis. Compared to Cluster A, Cluster B demonstrated higher levels and a greater diversity of immune cell infiltrations in CRG-related molecular patterns, suggesting a potential anti-inflammatory role in osteomyelitis. A diagnostic model for S. aureus-infected osteomyelitis, based on the three M2R-CRGs, was constructed, exhibiting excellent diagnostic performance and validated with an independent dataset. Significant upregulation in mRNA and protein expression levels of the three M2R-CRGs was observed in rat models of S. aureus-infected osteomyelitis, aligning with bioinformatic results. Conclusion The M2R-CRGs (SLC31A1, DLD, and MTF1) may be considered characteristic genes for early diagnosis and personalized immune therapy in patients with S. aureus-infected osteomyelitis.
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Affiliation(s)
- Xiangwen Shi
- Graduate School, Kunming Medical University, Kunming, People’s Republic of China
- Laboratory of Yunnan Traumatology and Orthopedics Clinical Medical Center, Yunnan Orthopedics and Sports Rehabilitation Clinical Medical Research Center, Department of Orthopedic Surgery, 920th Hospital of Joint Logistics Support Force of PLA, Kunming, People’s Republic of China
| | - Haonan Ni
- First People’s Hospital of Huzhou, the First affiliated Hospital of Huzhou University, Huzhou, People’s Republic of China
| | - Linmeng Tang
- Department of Radiology, the Second Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China
| | - Mingjun Li
- Laboratory of Yunnan Traumatology and Orthopedics Clinical Medical Center, Yunnan Orthopedics and Sports Rehabilitation Clinical Medical Research Center, Department of Orthopedic Surgery, 920th Hospital of Joint Logistics Support Force of PLA, Kunming, People’s Republic of China
| | - Yipeng Wu
- Laboratory of Yunnan Traumatology and Orthopedics Clinical Medical Center, Yunnan Orthopedics and Sports Rehabilitation Clinical Medical Research Center, Department of Orthopedic Surgery, 920th Hospital of Joint Logistics Support Force of PLA, Kunming, People’s Republic of China
| | - Yongqing Xu
- First People’s Hospital of Huzhou, the First affiliated Hospital of Huzhou University, Huzhou, People’s Republic of China
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Akaraphanth M, Nordgren TM, Gries CM. CXCR2 perturbation promotes Staphylococcus aureus implant-associated infection. J Med Microbiol 2024; 73:001821. [PMID: 38567642 PMCID: PMC11084549 DOI: 10.1099/jmm.0.001821] [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: 11/01/2023] [Accepted: 03/12/2024] [Indexed: 04/04/2024] Open
Abstract
Introduction. Staphylococcus aureus is the leading cause of acute medical implant infections, representing a significant modern medical concern. The success of S. aureus as a pathogen in these cases resides in its arsenal of virulence factors, resistance to multiple antimicrobials, mechanisms of immune modulation, and ability to rapidly form biofilms associated with implant surfaces. S. aureus device-associated, biofilm-mediated infections are often persistent and notoriously difficult to treat, skewing innate immune responses to promote chronic reoccurring infections. While relatively little is known of the role neutrophils play in response to acute S. aureus biofilm infections, these effector cells must be efficiently recruited to sites of infection via directed chemotaxis. Here we investigate the effects of modulating CXC chemokine receptor 2 (CXCR2) activity, predominantly expressed on neutrophils, during S. aureus implant-associated infection.Hypothesis. We hypothesize that modulation of CXCR2 expression and/or signalling activities during S. aureus infection, and thus neutrophil recruitment, extravasation and antimicrobial activity, will affect infection control and bacterial burdens in a mouse model of implant-associated infection.Aim. This investigation aims to elucidate the impact of altered CXCR2 activity during S. aureus biofilm-mediated infection that may help develop a framework for an effective novel strategy to prevent morbidity and mortality associated with implant infections.Methodology. To examine the role of CXCR2 during S. aureus implant infection, we employed a mouse model of indwelling subcutaneous catheter infection using a community-associated methicillin-resistant S. aureus (MRSA) strain. To assess the role of CXCR2 induction or inhibition during infection, treatment groups received daily intraperitoneal doses of either Lipocalin-2 (Lcn2) or AZD5069, respectively. At the end of the study, catheters and surrounding soft tissues were analysed for bacterial burdens and dissemination, and Cxcr2 transcription within the implant-associated tissues was quantified.Results. Mice treated with Lcn2 developed higher bacterial burdens within the soft tissue surrounding the implant site, which was associated with increased Cxcr2 expression. AZD5069 treatment also resulted in increased implant- and tissues-associated bacterial titres, as well as enhanced Cxcr2 expression.Conclusion. Our results demonstrate that CXCR2 plays an essential role in regulating the severity of S. aureus implant-associated infections. Interestingly, however, perturbation of CXCR2 expression or signalling both resulted in enhanced Cxcr2 transcription and elevated implant-associated bacterial burdens. Thus, CXCR2 appears finely tuned to efficiently recruit effector cells and mediate control of S. aureus biofilm-mediated infection.
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Affiliation(s)
- Mike Akaraphanth
- School of Medicine, University of Colorado, Aurora CO 80045, USA
| | - Tara M. Nordgren
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins CO 80523, USA
| | - Casey M. Gries
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins CO 80523, USA
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Yang B, Wang D, Yu S, Zhang C, Ai J, Yu X. Breaking CHIPS-Mediated immune evasion with tripterin to promote neutrophil chemotaxis against MRSA infection. Int Immunopharmacol 2024; 129:111597. [PMID: 38295543 DOI: 10.1016/j.intimp.2024.111597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 01/11/2024] [Accepted: 01/23/2024] [Indexed: 02/02/2024]
Abstract
Neutrophils are the most important innate immune cells in host defense against methicillin-resistant Staphylococcus aureus (MRSA). However, MRSA orchestrates precise and timely expression of a series of virulence factors, especially the chemotaxis inhibitory protein of Staphylococcus aureus (CHIPS), to evade neutrophil-mediated host defenses. Here, we demonstrated that tripterin, a plant-derived bioactive pentacyclic triterpenoid, had a low minimum inhibitory concentration (MIC) of 1.28 µg/mL and displayed excellent anti-MRSA activity in vitro and in vivo. RNA-seq and further knockdown experiments revealed that tripterin could dramatically downregulate the expression of CHIPS by regulating the SaeRS two-component regulatory system, thereby enhancing the chemotactic response of neutrophils. Furthermore, tripterin also displayed a potential inhibitory effect on biofilm components to enhance neutrophil infiltration into the interior of the biofilm. In a mouse bacteremia model, tripterin could still maintain an excellent therapeutic effect that was significantly better than that of the traditional antibiotic vancomycin. Overall, these results suggest that tripterin possesses a superior antibacterial activity via breaking CHIPS-mediated immune evasion to promote neutrophil chemotaxis, thus providing a novel strategy for combating serious pathogenic infections.
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Affiliation(s)
- Baoye Yang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
| | - Decheng Wang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
| | - Shi Yu
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
| | - Chengwei Zhang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
| | - Jing Ai
- School of Biomedical Engineering, Hainan University, Haikou, Hainan, China; Key Laboratory of Biomedical Engineering of Hainan Province, School of Biomedical Engineering, Hainan University, China
| | - Xiang Yu
- School of Biomedical Engineering, Hainan University, Haikou, Hainan, China; Key Laboratory of Biomedical Engineering of Hainan Province, School of Biomedical Engineering, Hainan University, China.
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Arciola CR, Ravaioli S, Mirzaei R, Dolzani P, Montanaro L, Daglia M, Campoccia D. Biofilms in Periprosthetic Orthopedic Infections Seen through the Eyes of Neutrophils: How Can We Help Neutrophils? Int J Mol Sci 2023; 24:16669. [PMID: 38068991 PMCID: PMC10706149 DOI: 10.3390/ijms242316669] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 11/13/2023] [Accepted: 11/16/2023] [Indexed: 12/18/2023] Open
Abstract
Despite advancements in our knowledge of neutrophil responses to planktonic bacteria during acute inflammation, much remains to be elucidated on how neutrophils deal with bacterial biofilms in implant infections. Further complexity transpires from the emerging findings on the role that biomaterials play in conditioning bacterial adhesion, the variety of biofilm matrices, and the insidious measures that biofilm bacteria devise against neutrophils. Thus, grasping the entirety of neutrophil-biofilm interactions occurring in periprosthetic tissues is a difficult goal. The bactericidal weapons of neutrophils consist of the following: ready-to-use antibacterial proteins and enzymes stored in granules; NADPH oxidase-derived reactive oxygen species (ROS); and net-like structures of DNA, histones, and granule proteins, which neutrophils extrude to extracellularly trap pathogens (the so-called NETs: an allusive acronym for "neutrophil extracellular traps"). Neutrophils are bactericidal (and therefore defensive) cells endowed with a rich offensive armamentarium through which, if frustrated in their attempts to engulf and phagocytose biofilms, they can trigger the destruction of periprosthetic bone. This study speculates on how neutrophils interact with biofilms in the dramatic scenario of implant infections, also considering the implications of this interaction in view of the design of new therapeutic strategies and functionalized biomaterials, to help neutrophils in their arduous task of managing biofilms.
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Affiliation(s)
- Carla Renata Arciola
- Laboratory of Immunorheumatology and Tissue Regeneration, Laboratory of Pathology of Implant Infections, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy;
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Via San Giacomo 14, 40126 Bologna, Italy
| | - Stefano Ravaioli
- Laboratorio di Patologia delle Infezioni Associate all’Impianto, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy; (S.R.); (D.C.)
| | - Rasoul Mirzaei
- Venom and Biotherapeutics Molecules Laboratory, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran 1316943551, Iran;
| | - Paolo Dolzani
- Laboratorio di Immunoreumatologia e Rigenerazione Tissutale, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy;
| | - Lucio Montanaro
- Laboratory of Immunorheumatology and Tissue Regeneration, Laboratory of Pathology of Implant Infections, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy;
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, Via San Giacomo 14, 40126 Bologna, Italy
| | - Maria Daglia
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131 Naples, Italy;
| | - Davide Campoccia
- Laboratorio di Patologia delle Infezioni Associate all’Impianto, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy; (S.R.); (D.C.)
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Yap CH, Ramle AQ, Lim SK, Rames A, Tay ST, Chin SP, Kiew LV, Tiekink ERT, Chee CF. Synthesis and Staphylococcus aureus biofilm inhibitory activity of indolenine-substituted pyrazole and pyrimido[1,2-b]indazole derivatives. Bioorg Med Chem 2023; 95:117485. [PMID: 37812886 DOI: 10.1016/j.bmc.2023.117485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/27/2023] [Accepted: 09/27/2023] [Indexed: 10/11/2023]
Abstract
Staphylococcus aureus is a highly adaptable opportunistic pathogen that can form biofilms and generate persister cells, leading to life-threatening infections that are difficult to treat with antibiotics alone. Therefore, there is a need for an effective S. aureus biofilm inhibitor to combat this public health threat. In this study, a small library of indolenine-substituted pyrazoles and pyrimido[1,2-b]indazole derivatives were synthesised, of which the hit compound exhibited promising antibiofilm activities against methicillin-susceptible S. aureus (MSSA ATCC 29213) and methicillin-resistant S. aureus (MRSA ATCC 33591) at concentrations significantly lower than the planktonic growth inhibition. The hit compound could prevent biofilm formation and eradicate mature biofilms of MSSA and MRSA, with a minimum biofilm inhibitory concentration (MBIC50) value as low as 1.56 µg/mL and a minimum biofilm eradication concentration (MBEC50) value as low as 6.25 µg/mL. The minimum inhibitory concentration (MIC) values of the hit compound against MSSA and MRSA were 50 µg/mL and 25 µg/mL, respectively, while the minimum bactericidal concentration (MBC) values against MSSA and MRSA were > 100 µg/mL. Preliminary structure-activity relationship analysis reveals that the fused benzene ring and COOH group of the hit compound are crucial for the antibiofilm activity. Additionally, the compound was not cytotoxic to human alveolar A549 cells, thus highlighting its potential as a suitable candidate for further development as a S. aureus biofilm inhibitor.
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Affiliation(s)
- Cheng Hong Yap
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Abdul Qaiyum Ramle
- School of Chemical Sciences, Universiti Sains Malaysia, 11800, Penang, Malaysia
| | - See Khai Lim
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Avinash Rames
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Sun Tee Tay
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia.
| | - Sek Peng Chin
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Lik Voon Kiew
- Department of Pharmacology, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia; Department of Biological Science and Technology, National Yang Ming Chiao Tung University, 30068 Hsinchu, Taiwan, Republic of China
| | - Edward R T Tiekink
- Research Centre for Crystalline Materials, School of Medical and Life Sciences, Sunway University, 47500, Selangor Darul Ehsan, Malaysia
| | - Chin Fei Chee
- Nanotechnology and Catalysis Research Centre, Universiti Malaya, 50603, Kuala Lumpur, Malaysia.
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6
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Xie P, Gao Y, Wu C, Li X, Yang Y. The inhibitory mechanism of echinacoside against Staphylococcus aureus Ser/Thr phosphatase Stp1 by virtual screening and molecular modeling. J Mol Model 2023; 29:320. [PMID: 37725157 DOI: 10.1007/s00894-023-05723-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 09/09/2023] [Indexed: 09/21/2023]
Abstract
CONTEXT Stp1 is a new potential target closely related to the pathogenicity of Staphylococcus aureus (S. aureus). In this study, effective Stp1 inhibitors were screened via virtual screening and enzyme activity experiments, and the inhibition mechanism was analyzed using molecular dynamics simulation. METHODS AutoDock Vina 4.0 software was used for virtual screening. The molecular structures of Stp1 and ligands were obtained from the RCSB Protein Data Bank and Zinc database, respectively. The molecular dynamics simulation used the Gromacs 4.5.5 software package with the Amberff99sb force field and TIP3P water model. AutoDock Tools was used to add polar hydrogen atoms to Stp1 and distribute part of the charge generated by Kollman's combined atoms. The binding free energies were calculated using the Amber 10 package. RESULTS The theoretical calculation results are consistent with the experimental results. We found that echinacoside (ECH) substantially inhibits the hydrolytic activity of Stp1. ECH competes with the substrate by binding to the active center of Stp1, resulting in a decrease in Stp1 activity. In addition, Met39, Gly41, Asp120, Asn162, and Ile163 were identified to play key roles in the binding of Stp1 to ECH. The benzene ring of ECH also plays an important role in complex binding. These findings provide a robust foundation for the development of innovative anti-infection drugs.
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Affiliation(s)
- Peng Xie
- Faculty of Food Science and Technology, Suzhou Polytechnic Institute of Agriculture, Suzhou, 215008, China
| | - Yue Gao
- Faculty of Food Science and Technology, Suzhou Polytechnic Institute of Agriculture, Suzhou, 215008, China
| | - Chenqi Wu
- Faculty of Food Science and Technology, Suzhou Polytechnic Institute of Agriculture, Suzhou, 215008, China
| | - Xuenan Li
- College of Food Science and Engineering, Jilin Agricultural University, Changchun, 130118, Jilin, China
| | - Yanan Yang
- Faculty of Food Science and Technology, Suzhou Polytechnic Institute of Agriculture, Suzhou, 215008, China.
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Venkateswaran P, Vasudevan S, David H, Shaktivel A, Shanmugam K, Neelakantan P, Solomon AP. Revisiting ESKAPE Pathogens: virulence, resistance, and combating strategies focusing on quorum sensing. Front Cell Infect Microbiol 2023; 13:1159798. [PMID: 37457962 PMCID: PMC10339816 DOI: 10.3389/fcimb.2023.1159798] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 06/08/2023] [Indexed: 07/18/2023] Open
Abstract
The human-bacterial association is long-known and well-established in terms of both augmentations of human health and attenuation. However, the growing incidents of nosocomial infections caused by the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter sp.) call for a much deeper understanding of these organisms. Adopting a holistic approach that includes the science of infection and the recent advancements in preventing and treating infections is imperative in designing novel intervention strategies against ESKAPE pathogens. In this regard, this review captures the ingenious strategies commissioned by these master players, which are teamed up against the defenses of the human team, that are equally, if not more, versatile and potent through an analogy. We have taken a basketball match as our analogy, dividing the human and bacterial species into two teams playing with the ball of health. Through this analogy, we make the concept of infectious biology more accessible.
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Affiliation(s)
- Parvathy Venkateswaran
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Sahana Vasudevan
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Helma David
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Adityan Shaktivel
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Karthik Shanmugam
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Prasanna Neelakantan
- Division of Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Adline Princy Solomon
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
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Yu F, Dong C, Zhang Y, Che R, Xie C, Liu Y, Zhang Z, Li L, Chen X, Cai X, Wang G, Li Y. GrpE and ComD contribute to the adherence, biofilm formation, and pathogenicity of Streptococcus suis. Arch Microbiol 2023; 205:159. [PMID: 37005968 DOI: 10.1007/s00203-023-03503-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/20/2023] [Accepted: 03/22/2023] [Indexed: 04/04/2023]
Abstract
Streptococcus suis is a major bacterial pathogen of swine and an emerging zoonotic agent that has to date resulted in substantial economic losses to the swine industry worldwide, and can cause persistent infection by forming biofilms. GrpE and histidine protein kinase ComD are important proteins implicated in the pathogenicity of S. suis, although whether they play roles in adhesion and biofilm formation has yet to be sufficiently clarified. In this study, we constructed grpE and comD deletion strains of S. suis by homologous recombination, and examined their cell adhesion and biofilm formation capacities compared with those of the wild-type strain. The pathogenicity of the grpE and comD deletion strains was evaluated using a mouse infection model, which revealed that compared with the wild-type, these deletion strains induced milder symptoms and lower bacteremia, as well as comparatively minor organ (brain, spleen, liver, and lung) lesions, in the infected mice. Moreover, the deletion of grpE and comD significantly reduced the pro-inflammatory cytokine (IL-6, IL-1β, and TNF-α) induction capacity of S. suis. Collectively, the findings of this study indicate that the GrpE and ComD proteins of Streptococcus suis play key roles in the adherence to PK-15 cells and the formation of biofilms, thereby contributing to the virulence of this pathogen.
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Affiliation(s)
- Fei Yu
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China
| | - Chunliu Dong
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China
| | - Yuefeng Zhang
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China
| | - Ruixiang Che
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163000, China
| | - Chunmei Xie
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China
| | - Yanyan Liu
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China
| | - Zhiyun Zhang
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China
| | - Lu Li
- College of Life Sciences, Northeast Agricultural University, Harbin, 150030, China
| | - Xueying Chen
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China
| | - Xuehui Cai
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150030, China
| | - Gang Wang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150030, China.
- Department of Basic Veterinary Medicine, College of Veterinary Medicine, Shandong Agricultural University, Taian, 271000, China.
| | - Yanhua Li
- Heilongjiang Key Laboratory for Animal Disease Control and Pharmaceutical Development, College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China.
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Cangui-Panchi SP, Ñacato-Toapanta AL, Enríquez-Martínez LJ, Salinas-Delgado GA, Reyes J, Garzon-Chavez D, Machado A. Battle royale: Immune response on biofilms – host-pathogen interactions. CURRENT RESEARCH IN IMMUNOLOGY 2023; 4:100057. [PMID: 37025390 PMCID: PMC10070391 DOI: 10.1016/j.crimmu.2023.100057] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/08/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023] Open
Abstract
The research interest of the scientific community in biofilm-forming microorganisms is growing due to the problems caused by their infections affecting humans and animals, mainly because of the difficulty of the host immune system in eradicating these microbial complex communities and the increasing antimicrobial resistance rates worldwide. This review describes the virulence factors and their interaction with the microbial communities of four well-known and highly biofilm-forming pathogens, more exactly, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus spp., and Candida spp. The innate and adaptive immune responses caused by the infection with these microorganisms and their evasion to the host immune system by biofilm formation are discussed in the present work. The relevance of the differences in the expression of certain virulence factors and the immune response in biofilm-associated infections when compared to planktonic infections is usually described as the biofilm architecture protects the pathogen and alters the host immune responses, here we extensively discussed these mechanisms.
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Affiliation(s)
- Sandra Pamela Cangui-Panchi
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Anahí Lizbeth Ñacato-Toapanta
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Leonardo Joshué Enríquez-Martínez
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Gabriela Alexandra Salinas-Delgado
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
| | - Jorge Reyes
- Hospital del Instituto Ecuatoriano de Seguridad Social (IESS) Quito-Sur, Quito, Ecuador
- Facultad de Ciencias Químicas, Universidad Central del Ecuador, Quito, Ecuador
| | - Daniel Garzon-Chavez
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias de la Salud, Quito, Ecuador
| | - António Machado
- Universidad San Francisco de Quito USFQ, Colegio de Ciencias Biológicas y Ambientales COCIBA, Instituto de Microbiología, Laboratorio de Bacteriología, Quito, Ecuador
- Corresponding author.
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Role of Staphylococcus aureus Formate Metabolism during Prosthetic Joint Infection. Infect Immun 2022; 90:e0042822. [PMID: 36286525 PMCID: PMC9670962 DOI: 10.1128/iai.00428-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Biofilms are bacterial communities characterized by antibiotic tolerance.
Staphylococcus aureus
is a leading cause of biofilm infections on medical devices, including prosthetic joints, which represent a significant health care burden. The major leukocyte infiltrate associated with
S. aureus
prosthetic joint infection (PJI) is granulocytic myeloid-derived suppressor cells (G-MDSCs), which produce IL-10 to promote biofilm persistence by inhibiting monocyte and macrophage proinflammatory activity.
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Masters EA, Ricciardi BF, Bentley KLDM, Moriarty TF, Schwarz EM, Muthukrishnan G. Skeletal infections: microbial pathogenesis, immunity and clinical management. Nat Rev Microbiol 2022; 20:385-400. [PMID: 35169289 PMCID: PMC8852989 DOI: 10.1038/s41579-022-00686-0] [Citation(s) in RCA: 143] [Impact Index Per Article: 71.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2022] [Indexed: 12/13/2022]
Abstract
Osteomyelitis remains one of the greatest risks in orthopaedic surgery. Although many organisms are linked to skeletal infections, Staphylococcus aureus remains the most prevalent and devastating causative pathogen. Important discoveries have uncovered novel mechanisms of S. aureus pathogenesis and persistence within bone tissue, including implant-associated biofilms, abscesses and invasion of the osteocyte lacuno-canalicular network. However, little clinical progress has been made in the prevention and eradication of skeletal infection as treatment algorithms and outcomes have only incrementally changed over the past half century. In this Review, we discuss the mechanisms of persistence and immune evasion in S. aureus infection of the skeletal system as well as features of other osteomyelitis-causing pathogens in implant-associated and native bone infections. We also describe how the host fails to eradicate bacterial bone infections, and how this new information may lead to the development of novel interventions. Finally, we discuss the clinical management of skeletal infection, including osteomyelitis classification and strategies to treat skeletal infections with emerging technologies that could translate to the clinic in the future.
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Affiliation(s)
- Elysia A Masters
- Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY, USA
- Department of Biomedical Engineering, University of Rochester Medical Center, Rochester, NY, USA
| | - Benjamin F Ricciardi
- Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY, USA
- Department of Orthopaedics and Rehabilitation, University of Rochester Medical Center, Rochester, NY, USA
| | - Karen L de Mesy Bentley
- Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY, USA
- Department of Orthopaedics and Rehabilitation, University of Rochester Medical Center, Rochester, NY, USA
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY, USA
| | | | - Edward M Schwarz
- Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY, USA.
- Department of Biomedical Engineering, University of Rochester Medical Center, Rochester, NY, USA.
- Department of Orthopaedics and Rehabilitation, University of Rochester Medical Center, Rochester, NY, USA.
| | - Gowrishankar Muthukrishnan
- Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY, USA
- Department of Orthopaedics and Rehabilitation, University of Rochester Medical Center, Rochester, NY, USA
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12
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Colonization and Infection of Indwelling Medical Devices by Staphylococcus aureus with an Emphasis on Orthopedic Implants. Int J Mol Sci 2022; 23:ijms23115958. [PMID: 35682632 PMCID: PMC9180976 DOI: 10.3390/ijms23115958] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 02/08/2023] Open
Abstract
The use of indwelling medical devices has constantly increased in recent years and has revolutionized the quality of life of patients affected by different diseases. However, despite the improvement of hygiene conditions in hospitals, implant-associated infections remain a common and serious complication in prosthetic surgery, mainly in the orthopedic field, where infection often leads to implant failure. Staphylococcus aureus is the most common cause of biomaterial-centered infection. Upon binding to the medical devices, these bacteria proliferate and develop dense communities encased in a protective matrix called biofilm. Biofilm formation has been proposed as occurring in several stages-(1) attachment; (2) proliferation; (3) dispersal-and involves a variety of host and staphylococcal proteinaceous and non-proteinaceous factors. Moreover, biofilm formation is strictly regulated by several control systems. Biofilms enable staphylococci to avoid antimicrobial activity and host immune response and are a source of persistent bacteremia as well as of localized tissue destruction. While considerable information is available on staphylococcal biofilm formation on medical implants and important results have been achieved on the treatment of biofilms, preclinical and clinical applications need to be further investigated. Thus, the purpose of this review is to gather current studies about the mechanism of infection of indwelling medical devices by S. aureus with a special focus on the biochemical factors involved in biofilm formation and regulation. We also provide a summary of the current therapeutic strategies to combat biomaterial-associated infections and highlight the need to further explore biofilm physiology and conduct research for innovative anti-biofilm approaches.
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13
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Caldara M, Belgiovine C, Secchi E, Rusconi R. Environmental, Microbiological, and Immunological Features of Bacterial Biofilms Associated with Implanted Medical Devices. Clin Microbiol Rev 2022; 35:e0022120. [PMID: 35044203 PMCID: PMC8768833 DOI: 10.1128/cmr.00221-20] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The spread of biofilms on medical implants represents one of the principal triggers of persistent and chronic infections in clinical settings, and it has been the subject of many studies in the past few years, with most of them focused on prosthetic joint infections. We review here recent works on biofilm formation and microbial colonization on a large variety of indwelling devices, ranging from heart valves and pacemakers to urological and breast implants and from biliary stents and endoscopic tubes to contact lenses and neurosurgical implants. We focus on bacterial abundance and distribution across different devices and body sites and on the role of environmental features, such as the presence of fluid flow and properties of the implant surface, as well as on the interplay between bacterial colonization and the response of the human immune system.
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Affiliation(s)
- Marina Caldara
- Interdepartmental Center on Safety, Technologies, and Agri-food Innovation (SITEIA.PARMA), University of Parma, Parma, Italy
| | - Cristina Belgiovine
- IRCCS Humanitas Research Hospital, Rozzano–Milan, Italy
- Scuola di Specializzazione in Microbiologia e Virologia, Università degli Studi di Pavia, Pavia, Italy
| | - Eleonora Secchi
- Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
| | - Roberto Rusconi
- IRCCS Humanitas Research Hospital, Rozzano–Milan, Italy
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele–Milan, Italy
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14
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Mirzaei R, Sabokroo N, Ahmadyousefi Y, Motamedi H, Karampoor S. Immunometabolism in biofilm infection: lessons from cancer. Mol Med 2022; 28:10. [PMID: 35093033 PMCID: PMC8800364 DOI: 10.1186/s10020-022-00435-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 01/10/2022] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Biofilm is a community of bacteria embedded in an extracellular matrix, which can colonize different human cells and tissues and subvert the host immune reactions by preventing immune detection and polarizing the immune reactions towards an anti-inflammatory state, promoting the persistence of biofilm-embedded bacteria in the host. MAIN BODY OF THE MANUSCRIPT It is now well established that the function of immune cells is ultimately mediated by cellular metabolism. The immune cells are stimulated to regulate their immune functions upon sensing danger signals. Recent studies have determined that immune cells often display distinct metabolic alterations that impair their immune responses when triggered. Such metabolic reprogramming and its physiological implications are well established in cancer situations. In bacterial infections, immuno-metabolic evaluations have primarily focused on macrophages and neutrophils in the planktonic growth mode. CONCLUSION Based on differences in inflammatory reactions of macrophages and neutrophils in planktonic- versus biofilm-associated bacterial infections, studies must also consider the metabolic functions of immune cells against biofilm infections. The profound characterization of the metabolic and immune cell reactions could offer exciting novel targets for antibiofilm therapy.
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Affiliation(s)
- Rasoul Mirzaei
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
- Venom and Biotherapeutics Molecules Lab, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
| | - Niloofar Sabokroo
- Department of Microbiology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Yaghoub Ahmadyousefi
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Hamadan University of Medical Sciences, Hamadan, Iran
- Research Center for Molecular Medicine, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Hamid Motamedi
- Department of Microbiology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Sajad Karampoor
- Gastrointestinal and Liver Diseases Research Center, Iran University of Medical Sciences, Tehran, Iran.
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.
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15
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SpoT-mediated NapA upregulation promotes oxidative stress-induced Helicobacter pylori biofilm formation and confers multidrug resistance. Antimicrob Agents Chemother 2021; 65:AAC.00152-21. [PMID: 33649116 PMCID: PMC8092859 DOI: 10.1128/aac.00152-21] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Recently, there is increased incidence of drug-resistant Helicobacter pylori infection. Biofilm formation confers multidrug resistance to bacteria. Moreover, it has been found that the formation of biofilm on the surface of gastric mucosa is an important reason for the difficulty of eradication of H. pylori The mechanisms underlying H. pylori biofilm formation in vivo have not been elucidated. Reactive oxygen species (ROS) released by the host immune cells in response to H. pylori infection cannot effectively clear the pathogen. Moreover, the extracellular matrix of the biofilm protects the bacteria against ROS-mediated toxicity. This study hypothesized that ROS can promote H. pylori biofilm formation and treatment with low concentrations of hydrogen peroxide (H2O2) promoted this process in vitro The comparative transcriptome analysis of planktonic and biofilm-forming cells revealed that the expression of SpoT, a (p)ppGpp (guanosine 3'-diphosphate 5'-triphosphate and guanosine 3',5'-bispyrophosphate) synthetase/hydrolase, is upregulated in H2O2-induced biofilms and that knockout of spoT inhibited H. pylori biofilm formation. Additionally, this study examined the key target molecules involved in SpoT regulation using weighted gene co-expression network analysis. The analysis revealed that neutrophil-activating protein (NapA; HP0243) promoted H2O2-induced biofilm formation and conferred multidrug resistance. Furthermore, vitamin C exhibited anti-H. pylori biofilm activity and downregulated the expression of napA in vitro These findings provide novel insight into the clearance of H. pylori biofilms.
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16
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Dauros-Singorenko P, Wiles S, Swift S. Staphylococcus aureus Biofilms and Their Response to a Relevant in vivo Iron Source. Front Microbiol 2020; 11:509525. [PMID: 33408695 PMCID: PMC7779473 DOI: 10.3389/fmicb.2020.509525] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 11/23/2020] [Indexed: 11/29/2022] Open
Abstract
Biofilm infections can be chronic, life threatening and challenging to eradicate. Understanding in vivo stimuli affecting the biofilm cycle is one step toward targeted prevention strategies. Iron restriction by the host is a stimulus for biofilm formation for some Staphylococcus aureus isolates; however, in some infection scenarios bacteria are exposed to abundant amounts of hemoglobin (Hb), which S. aureus is able to use as iron source. Thus, we hypothesized a role for Hb in the biofilm infection. Microplate “biofilm” assays showed biofilm-matrix production was increased in the presence of hemoglobin when compared to the provision of iron as an inorganic salt. Microscopic analysis of biofilms showed that the provision of iron as hemoglobin consistently caused thicker and more structured biofilms when compared to the effect of the inorganic iron source. Iron responsive biofilm gene expression analysis showed that Agr Quorum Sensing, a known biofilm dispersal marker, was repressed with hemoglobin but induced with an equivalent amount of inorganic iron in the laboratory strain Newman. The gene expression of two biofilm structuring agents, PSMα and PSMβ, differed in the response to the iron source provided and was not correlated to hemoglobin-structured biofilms. A comparison of the model pathogen S. aureus Newman with local clinical isolates demonstrated that while there was a similar phenotypic biofilm response to hemoglobin, there was substantial variation in the expression of key biofilm dispersal markers, suggesting an underappreciated variation in biofilm regulome among S. aureus isolates and that no general inferences can be made by studying the behavior of single strains.
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Affiliation(s)
- Priscila Dauros-Singorenko
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Siouxsie Wiles
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Simon Swift
- Department of Molecular Medicine and Pathology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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17
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Gries CM, Rivas Z, Chen J, Lo DD. Intravital Multiphoton Examination of Implant-Associated Staphylococcus aureus Biofilm Infection. Front Cell Infect Microbiol 2020; 10:574092. [PMID: 33178628 PMCID: PMC7593243 DOI: 10.3389/fcimb.2020.574092] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 09/10/2020] [Indexed: 12/13/2022] Open
Abstract
Bacterial infections associated with implanted medical devices represents a healthcare crisis due to their persistence, antibiotic tolerance, and immune avoidance. Indwelling devices are rapidly coated with host plasma and extracellular matrix proteins which can then be exploited by bacterial pathogens for adherence and subsequent biofilm development. Our understanding of the host-pathogen interface that determines the fate of biofilm-mediated infections is limited to the experimental models employed by laboratories studying these organisms. Current in vivo models of biofilm-mediated infection, while certainly useful, are typically limited to end-point analyses of bacterial burden enumeration, immune cell profiling, and cytokine/chemokine analysis. Thus, with these models, the complex, real-time assessment of biofilm development and innate immune cell activity remains imperceptible. Here, we describe a novel murine biofilm infection model employing time-lapse intravital multiphoton microscopy which permits concurrent and real-time visualization of Staphylococcus aureus biofilm formation and immune cell activity. Using cell tracking, we found that S. aureus biofilms impede neutrophil chemotaxis, redirecting their migration patterns to prevent biofilm invasion. This approach is the first to directly examine device-associated biofilm development and host-pathogen interactions and will serve to both further our understanding of infection development and help reveal the effects of future antibiofilm treatment strategies.
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Affiliation(s)
- Casey M Gries
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Zuivanna Rivas
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - Justin Chen
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
| | - David D Lo
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, CA, United States
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18
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Willing S, Dyer E, Schneewind O, Missiakas D. FmhA and FmhC of Staphylococcus aureus incorporate serine residues into peptidoglycan cross-bridges. J Biol Chem 2020; 295:13664-13676. [PMID: 32759309 PMCID: PMC7521636 DOI: 10.1074/jbc.ra120.014371] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 08/03/2020] [Indexed: 12/16/2022] Open
Abstract
Staphylococcal peptidoglycan is characterized by pentaglycine cross-bridges that are cross-linked between adjacent wall peptides by penicillin-binding proteins to confer robustness and flexibility. In Staphylococcus aureus, pentaglycine cross-bridges are synthesized by three proteins: FemX adds the first glycine, and the homodimers FemA and FemB sequentially add two Gly-Gly dipeptides. Occasionally, serine residues are also incorporated into the cross-bridges by enzymes that have heretofore not been identified. Here, we show that the FemA/FemB homologues FmhA and FmhC pair with FemA and FemB to incorporate Gly-Ser dipeptides into cross-bridges and to confer resistance to lysostaphin, a secreted bacteriocin that cleaves the pentaglycine cross-bridge. FmhA incorporates serine residues at positions 3 and 5 of the cross-bridge. In contrast, FmhC incorporates a single serine at position 5. Serine incorporation also lowers resistance toward oxacillin, an antibiotic that targets penicillin-binding proteins, in both methicillin-sensitive and methicillin-resistant strains of S. aureus FmhC is encoded by a gene immediately adjacent to lytN, which specifies a hydrolase that cleaves the bond between the fifth glycine of cross-bridges and the alanine of the adjacent stem peptide. In this manner, LytN facilitates the separation of daughter cells. Cell wall damage induced upon lytN overexpression can be alleviated by overexpression of fmhC. Together, these observations suggest that FmhA and FmhC generate peptidoglycan cross-bridges with unique serine patterns that provide protection from endogenous murein hydrolases governing cell division and from bacteriocins produced by microbial competitors.
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Affiliation(s)
- Stephanie Willing
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
| | - Emma Dyer
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
| | - Olaf Schneewind
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
| | - Dominique Missiakas
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA; Howard Taylor Ricketts Laboratory, Argonne National Laboratory, Lemont, Illinois, USA.
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19
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Leukocidins and the Nuclease Nuc Prevent Neutrophil-Mediated Killing of Staphylococcus aureus Biofilms. Infect Immun 2020; 88:IAI.00372-20. [PMID: 32719153 DOI: 10.1128/iai.00372-20] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 07/17/2020] [Indexed: 02/07/2023] Open
Abstract
Bacterial biofilms are linked with chronic infections and have properties distinct from those of planktonic, single-celled bacteria. The virulence mechanisms associated with Staphylococcus aureus biofilms are becoming better understood. Human neutrophils are critical for the innate immune response to S. aureus infection. Here, we describe two virulence strategies that converge to promote the ability of S. aureus biofilms to evade killing by neutrophils. Specifically, we show that while neutrophils exposed to S. aureus biofilms produce extracellular traps (NETs) and phagocytose bacteria, both mechanisms are inefficient in clearance of the biofilm biomass. This is attributed to the leukocidin LukAB, which promotes S. aureus survival during phagocytosis. We also show that the persistence of biofilm bacteria trapped in NETs is facilitated by S. aureus nuclease (Nuc)-mediated degradation of NET DNA. This study describes key aspects of the interaction between primary human neutrophils and S. aureus biofilms and provides insight into how S. aureus evades the neutrophil response to cause persistent infections.
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20
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Mirzaei R, Mohammadzadeh R, Sholeh M, Karampoor S, Abdi M, Dogan E, Moghadam MS, Kazemi S, Jalalifar S, Dalir A, Yousefimashouf R, Mirzaei E, Khodavirdipour A, Alikhani MY. The importance of intracellular bacterial biofilm in infectious diseases. Microb Pathog 2020; 147:104393. [PMID: 32711113 DOI: 10.1016/j.micpath.2020.104393] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/17/2022]
Abstract
Various bacterial species, previously known as extracellular pathogens, can reside inside different host cells by adapting to intracellular modes by forming microbial aggregates with similar characteristics to bacterial biofilms. Additionally, bacterial invasion of human cells leads to failure in antibiotic therapy, as most conventional anti-bacterial agents cannot reach intracellular biofilm in normal concentrations. Various studies have shown that bacteria such as uropathogenic Escherichia coli, Pseudomonas aeruginosa, Borrelia burgdorferi,Moraxella catarrhalis, non-typeable Haemophilus influenzae, Streptococcus pneumonia, and group A Streptococci produce biofilm-like structures within the host cells. For the first time in this review, we will describe and discuss the new information about intracellular bacterial biofilm formation and its importance in bacterial infectious diseases.
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Affiliation(s)
- Rasoul Mirzaei
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran; Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Rokhsareh Mohammadzadeh
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Sholeh
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Sajad Karampoor
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Milad Abdi
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Student Research Committee, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Eyup Dogan
- Department of Basic Biotechnology, Biotechnology Institute, Ankara, Turkey
| | - Mohammad Shokri Moghadam
- Department of Microbiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Sima Kazemi
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Saba Jalalifar
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Amine Dalir
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Rasoul Yousefimashouf
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Ebrahim Mirzaei
- Department of Medical Genetics and Molecular Biology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Amir Khodavirdipour
- Division of Humann Genetics, Department of Anatomy, St. John's Hospital, Bangalore, India
| | - Mohammad Yousef Alikhani
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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21
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de Vor L, Rooijakkers SHM, van Strijp JAG. Staphylococci evade the innate immune response by disarming neutrophils and forming biofilms. FEBS Lett 2020; 594:2556-2569. [PMID: 32144756 DOI: 10.1002/1873-3468.13767] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/30/2020] [Accepted: 02/22/2020] [Indexed: 12/24/2022]
Abstract
Staphylococcus aureus and Staphylococcus epidermidis can cause many types of infections, ranging from skin infections to implant-associated infections. The primary innate immune response against bacterial infections involves complement activation, recruitment of phagocytes (most importantly neutrophils), and subsequent killing of the pathogen. However, staphylococci are not innocent bystanders; they actively obstruct this immune attack. To do that, S. aureus secretes several immune-evasion proteins to resist attack by the innate immune system. Furthermore, S. aureus and S. epidermidis are known for their ability to form biofilms on implanted medical devices and host tissues, which provides another important immune-evasion mechanism. Understanding these different strategies to resist immune attack will help to develop novel therapies against staphylococcal infections.
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Affiliation(s)
- Lisanne de Vor
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, The Netherlands
| | - Suzan H M Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, The Netherlands
| | - Jos A G van Strijp
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht University, The Netherlands
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22
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Hofstee MI, Muthukrishnan G, Atkins GJ, Riool M, Thompson K, Morgenstern M, Stoddart MJ, Richards RG, Zaat SAJ, Moriarty TF. Current Concepts of Osteomyelitis: From Pathologic Mechanisms to Advanced Research Methods. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 190:1151-1163. [PMID: 32194053 DOI: 10.1016/j.ajpath.2020.02.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/18/2020] [Accepted: 02/27/2020] [Indexed: 01/18/2023]
Abstract
Osteomyelitis is an inflammation of the bone and bone marrow that is most commonly caused by a Staphylococcus aureus infection. Much of our understanding of the underlying pathophysiology of osteomyelitis, from the perspective of both host and pathogen, has been revised in recent years, with notable discoveries including the role played by osteocytes in the recruitment of immune cells, the invasion and persistence of S. aureus in submicron channels of cortical bone, and the diagnostic role of polymorphonuclear cells in implant-associated osteomyelitis. Advanced in vitro cell culture models, such as ex vivo culture models or organoids, have also been developed over the past decade, and have become widespread in many fields, including infectious diseases. These models better mimic the in vivo environment, allow the use of human cells, and can reduce our reliance on animals in osteomyelitis research. In this review, we provide an overview of the main pathologic concepts in osteomyelitis, with a focus on the new discoveries in recent years. Furthermore, we outline the value of modern in vitro cell culture techniques, with a focus on their current application to infectious diseases and osteomyelitis in particular.
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Affiliation(s)
- Marloes I Hofstee
- AO Research Institute Davos, Davos, Switzerland; Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Infection and Immunity Institute, Amsterdam, the Netherlands
| | - Gowrishankar Muthukrishnan
- Center for Musculoskeletal Research and Department of Orthopaedics, University of Rochester Medical Center, Rochester, New York
| | - Gerald J Atkins
- Centre for Orthopaedic and Trauma Research, University of Adelaide, Adelaide, South Australia, Australia
| | - Martijn Riool
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Infection and Immunity Institute, Amsterdam, the Netherlands
| | | | - Mario Morgenstern
- Department of Orthopedic Surgery and Traumatology, University Hospital Basel, Basel, Switzerland
| | | | | | - Sebastian A J Zaat
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Infection and Immunity Institute, Amsterdam, the Netherlands
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23
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Abdul Hamid AI, Nakusi L, Givskov M, Chang YT, Marquès C, Gueirard P. A mouse ear skin model to study the dynamics of innate immune responses against Staphylococcus aureus biofilms. BMC Microbiol 2020; 20:22. [PMID: 31996131 PMCID: PMC6990489 DOI: 10.1186/s12866-019-1635-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 11/07/2019] [Indexed: 11/10/2022] Open
Abstract
Background Staphylococcus aureus is a human pathogen that is a common cause of nosocomial infections and infections on indwelling medical devices, mainly due to its ability to shift between the planktonic and the biofilm/sessile lifestyle. Biofilm infections present a serious problem in human medicine as they often lead to bacterial persistence and thus to chronic infections. The immune responses elicited by biofilms have been described as specific and ineffective. In the few experiments performed in vivo, the importance of neutrophils and macrophages as a first line of defence against biofilm infections was clearly established. However, the bilateral interactions between biofilms and myeloid cells remain poorly studied and analysis of the dynamic processes at the cellular level in tissues inoculated with biofilm bacteria is still an unexplored field. It is urgent, therefore, to develop biologically sound experimental approaches in vivo designed to extract specific immune signatures from the planktonic and biofilm forms of bacteria. Results We propose an in vivo transgenic mouse model, used in conjunction with intravital confocal microscopy to study the dynamics of host inflammatory responses to bacteria. Culture conditions were created to prepare calibrated inocula of fluorescent planktonic and biofilm forms of bacteria. A confocal imaging acquisition and analysis protocol was then drawn up to study the recruitment of innate immune cells in the skin of LysM-EGFP transgenic mice. Using the mouse ear pinna model, we showed that inflammatory responses to S. aureus can be quantified over time and that the dynamics of innate immune cells after injection of either the planktonic or biofilm form can be characterized. First results showed that the ability of phagocytic cells to infiltrate the injection site and their motility is not the same in planktonic and biofilm forms of bacteria despite the cells being considerably recruited in both cases. Conclusion We developed a mouse model of infection to compare the dynamics of the inflammatory responses to planktonic and biofilm bacteria at the tissue and cellular levels. The mouse ear pinna model is a powerful imaging system to analyse the mechanisms of biofilm tolerance to immune attacks.
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Affiliation(s)
- Aizat Iman Abdul Hamid
- Laboratoire Microorganismes : Génome et Environnement, UMR CNRS 6023, Université Clermont-Auvergne, Clermont Ferrand, France
| | - Laurence Nakusi
- Laboratoire Microorganismes : Génome et Environnement, UMR CNRS 6023, Université Clermont-Auvergne, Clermont Ferrand, France
| | - Mickael Givskov
- Costerton Biofilm Center, department of Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Young-Tae Chang
- Center for Self-assembly and Complexity, IBS and Department of Chemistry, POSTECH, Pohang, Republic of Korea
| | - Claire Marquès
- Laboratoire Microorganismes : Génome et Environnement, UMR CNRS 6023, Université Clermont-Auvergne, Clermont Ferrand, France
| | - Pascale Gueirard
- Laboratoire Microorganismes : Génome et Environnement, UMR CNRS 6023, Université Clermont-Auvergne, Clermont Ferrand, France.
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Wu S, Liu Y, Lei L, Zhang H. Virulence of methicillin-resistant Staphylococcus aureus modulated by the YycFG two-component pathway in a rat model of osteomyelitis. J Orthop Surg Res 2019; 14:433. [PMID: 31831035 PMCID: PMC6909630 DOI: 10.1186/s13018-019-1508-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 12/04/2019] [Indexed: 02/07/2023] Open
Abstract
Objectives Methicillin-resistant Staphylococcus aureus (MRSA) strains present an urgent medical problem in osteomyelitis cases. Our previous study indicated that the YycFG two-component regulatory pathway is associated with the bacterial biofilm organization of MRSA strains. The aim of this study was to investigate the regulatory roles of ASyycG in the bacterial biofilm formation and the pathogenicity of MRSA strains using an antisense RNA strategy. Methods An ASyycG-overexpressing MRSA clinical isolate was constructed. The bacterial growth was monitored, and the biofilm biomass on bone specimens was examined using scanning electron microscopy and confocal laser scanning microscopy. Furthermore, quantitative RT-PCR (QRT-PCR) analysis was used to measure the expression of yycF/G/H and icaA/D in the MRSA and ASyycG strains. The expression of the YycG protein was quantified by Western blot assays. We validated the role of ASyycG in the invasive ability and pathogenicity of the strains in vivo using histology and peptide nucleic acid fluorescent in situ hybridization. Results The results showed that overexpression of ASyycG lead to a reduction in biofilm formation and exopolysaccharide (EPS) synthesis compared to the control MRSA strains. The ASyycG strains exhibited decreased expression of the yycF/G/H and icaA/D genes. Furthermore, Western blot data showed that the production of the YycG protein was inhibited in the ASyycG strains. In addition, we demonstrated that ASyycG suppressed the invasive ability and pathogenicity of the strain in vivo using an SPF (specific pathogen free) rat model. Conclusion In summary, the overexpression of ASyycG leads to a reduction in biofilm formation and bacterial pathogenicity in vivo, which provides a potential target for the management of MRSA-induced osteomyelitis.
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Affiliation(s)
- Shizhou Wu
- Department of Orthopedics, West China Hospital, Sichuan University, No.37 Guoxue Alley, Chengdu City, 610041, Sichuan, China
| | - Yunjie Liu
- West China School of Public Health, Sichuan University, Chengdu, China
| | - Lei Lei
- State Key Laboratory of Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, NO.14 Renmin South Road, Chengdu City, 610041, Sichuan, China.
| | - Hui Zhang
- Department of Orthopedics, West China Hospital, Sichuan University, No.37 Guoxue Alley, Chengdu City, 610041, Sichuan, China.
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25
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Seebach E, Kubatzky KF. Chronic Implant-Related Bone Infections-Can Immune Modulation be a Therapeutic Strategy? Front Immunol 2019; 10:1724. [PMID: 31396229 PMCID: PMC6664079 DOI: 10.3389/fimmu.2019.01724] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/09/2019] [Indexed: 12/14/2022] Open
Abstract
Chronic implant-related bone infections are a major problem in orthopedic and trauma-related surgery with severe consequences for the affected patients. As antibiotic resistance increases in general and because most antibiotics have poor effectiveness against biofilm-embedded bacteria in particular, there is a need for alternative and innovative treatment approaches. Recently, the immune system has moved into focus as the key player in infection defense and bone homeostasis, and the targeted modulation of the host response is becoming an emerging field of interest. The aim of this review was to summarize the current knowledge of impaired endogenous defense mechanisms that are unable to prevent chronicity of bone infections associated with a prosthetic or osteosynthetic device. The presence of foreign material adversely affects the immune system by generating a local immune-compromised environment where spontaneous clearance of planktonic bacteria does not take place. Furthermore, the surface structure of the implant facilitates the transition of bacteria from the planktonic to the biofilm stage. Biofilm formation on the implant surface is closely linked to the development of a chronic infection, and a misled adaption of the immune system makes it impossible to effectively eliminate biofilm infections. The interaction between the immune system and bone cells, especially osteoclasts, is extensively studied in the field of osteoimmunology and this crosstalk further aggravates the course of bone infection by shifting bone homeostasis in favor of bone resorption. T cells play a major role in various chronic diseases and in this review a special focus was therefore set on what is known about an ineffective T cell response. Myeloid-derived suppressor cells (MDSCs), anti-inflammatory macrophages, regulatory T cells (Tregs) as well as osteoclasts all suppress immune defense mechanisms and negatively regulate T cell-mediated immunity. Thus, these cells are considered to be potential targets for immune therapy. The success of immune checkpoint inhibition in cancer treatment encourages the transfer of such immunological approaches into treatment strategies of other chronic diseases. Here, we discuss whether immune modulation can be a therapeutic tool for the treatment of chronic implant-related bone infections.
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Affiliation(s)
- Elisabeth Seebach
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University Hospital, Heidelberg, Germany
| | - Katharina F Kubatzky
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University Hospital, Heidelberg, Germany
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26
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Wu S, Liu Y, Lei L, Zhang H. Antisense yycG Regulation of Antibiotic Sensitivity of Methicillin-Resistant Staphylococcus aureus in Chronic Osteomyelitis. Surg Infect (Larchmt) 2019; 20:472-479. [PMID: 31038392 DOI: 10.1089/sur.2019.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Background: Methicillin-resistant Staphylococcus aureus (MRSA) is an urgent medical problem in osteomyelitis. The YycFG two-component regulatory system (TCS) allows bacteria to adapt rapidly to physical, chemical, and biological stresses. The recombinant plasmid shuttle vector was used to overexpress an antisense RNA (asRNA) to inhibit target gene expression by sequence-specific double-stranded RNA complex degradation. In the current study, antisense yycG RNA (ASyycG)-overexpression MRSA clinical isolates were constructed. Methods: Bacterial growth was monitored, and biofilm biomass was determined by crystal violet microtiter assay. Quantitative reverse transcription polymerase chain reaction analysis was used to identify expression of yycF/G/H and icaA/D in MRSA and ASyycG strains. The expression of YycG protein was quantified by Western blot assays. The antibiotic resistance of ASyycG strains was compared with that of the MRSA strains. Results: The ASyycG strains showed a decrease in growth rate compared with the MRSA strains. Of note, overexpression of ASyycG led to a reduction in biofilm formation and adhesion force. ASyycG strains had decreased expressions of the yycF/G/H and icaA/D. Furthermore, Western blot data showed that expression of the YycG protein decreased by 40% in ASyycG strains compared with MRSA strains. In addition, the effect of yycG asRNA improved the susceptibility of ASyycG strains to cefoxitin. Conclusions: The ASyycG strains inhibited biofilm organization and increased antibiotic sensitivity, which may be attributed to altered intracellular polysaccharide construction.
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Affiliation(s)
- Shizhou Wu
- 1Department of Orthopedics, West China Hospital, West China Medical School, Sichuan University, Chengdu, China.,2State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yunjie Liu
- 3West China School of Public Health, Sichuan University, Chengdu, Sichuan, China
| | - Lei Lei
- 2State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Hui Zhang
- 1Department of Orthopedics, West China Hospital, West China Medical School, Sichuan University, Chengdu, China
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27
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Khan MM, Chattagul S, Tran BQ, Freiberg JA, Nita-Lazar A, Shirtliff ME, Sermswan RW, Ernst RK, Goodlett DR. Temporal proteomic profiling reveals changes that support Burkholderia biofilms. Pathog Dis 2019; 77:ftz005. [PMID: 30759239 PMCID: PMC6482045 DOI: 10.1093/femspd/ftz005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 02/12/2019] [Indexed: 12/14/2022] Open
Abstract
Melioidosis associated with opportunistic pathogen Burkholderia pseudomallei imparts a huge medical burden in Southeast Asia and Australia. At present there is no available human vaccine that protects against B. pseudomallei infection and antibiotic treatments are limited particularly for drug-resistant strains and bacteria in biofilm forms. Biofilm forming bacteria exhibit phenotypic features drastically different to their planktonic states, often exhibiting a diminished response to antimicrobial therapies. Our earlier work on global profiling of bacterial biofilms using transcriptomics and proteomics revealed transcript-decoupled protein abundance in bacterial biofilms. Here we employed reverse phase liquid chromatography tandem mass spectrometry (LC-MS/MS) to deduce temporal proteomic differences in planktonic and biofilm forms of Burkholderia thailandensis, which is weakly surrogate model of pathogenic B. pseudomallei as sharing a key element in genomic similarity. The proteomic analysis of B. thailandensis in biofilm versus planktonic states revealed that proteome changes support biofilm survival through decreased abundance of metabolic proteins while increased abundance of stress-related proteins. Interestingly, the protein abundance including for the transcription protein TEX, outer periplasmic TolB protein, and the exopolyphosphatase reveal adaption in bacterial biofilms that facilitate antibiotic tolerance through a non-specific mechanism. The present proteomics study of B. thailandensis biofilms provides a global snapshot of protein abundance differences and antimicrobial sensitivities in planktonic and sessile bacteria.
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Affiliation(s)
- Mohd M Khan
- University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Laboratory of Immune System Biology (LISB), National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD 20814, USA
| | - Supaksorn Chattagul
- Melioidosis Research Center, Khon Kaen University, Khon Kaen 40002, Thailand
- Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Bao Q Tran
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA
| | - Jeffrey A Freiberg
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Aleksandra Nita-Lazar
- Laboratory of Immune System Biology (LISB), National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), Bethesda, MD 20814, USA
| | - Mark E Shirtliff
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - Rasana W Sermswan
- Melioidosis Research Center, Khon Kaen University, Khon Kaen 40002, Thailand
- Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - David R Goodlett
- Department of Microbial Pathogenesis, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
- International Centre for Cancer Vaccine Science, University of Gdansk, 80-308 Gdańsk, Poland
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28
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Abouelhassan Y, Zhang Y, Jin S, Huigens RW. Transcript Profiling of MRSA Biofilms Treated with a Halogenated Phenazine Eradicating Agent: A Platform for Defining Cellular Targets and Pathways Critical to Biofilm Survival. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal ChemistryCenter for Natural Products, Drug Discovery and Development (CNPD3)College of PharmacyUniversity of Florida 1345 Center Drive Gainesville FL USA
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research (ICBR)Gene Expression and GenotypingUniversity of Florida USA
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of MedicineUniversity of Florida USA
| | - Robert W. Huigens
- Department of Medicinal ChemistryCenter for Natural Products, Drug Discovery and Development (CNPD3)College of PharmacyUniversity of Florida 1345 Center Drive Gainesville FL USA
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29
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Abouelhassan Y, Zhang Y, Jin S, Huigens RW. Transcript Profiling of MRSA Biofilms Treated with a Halogenated Phenazine Eradicating Agent: A Platform for Defining Cellular Targets and Pathways Critical to Biofilm Survival. Angew Chem Int Ed Engl 2018; 57:15523-15528. [PMID: 30230671 DOI: 10.1002/anie.201809785] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Indexed: 01/09/2023]
Abstract
Bacterial biofilms are surface-attached communities of non-replicating bacteria innately tolerant to antibiotics. Biofilms display differential gene expression profiles and physiologies as compared to their planktonic counterparts; however, their biology remains largely unknown. In this study, we used a halogenated phenazine (HP) biofilm eradicator in transcript profiling experiments (RNA-seq) to define cellular targets and pathways critical to biofilm viability. WoPPER analysis with time-course validation (RT-qPCR) revealed that HP-14 induces rapid iron starvation in MRSA biofilms, as evident by the activation of iron-acquisition gene clusters in 1 hour. Serine proteases and oligopeptide transporters were also found to be up-regulated, whereas glycolysis, arginine deiminase, and urease gene clusters were down-regulated. KEGG analysis revealed that HP-14 impacts metabolic and ABC transporter functional pathways. These findings suggest that MRSA biofilm viability relies on iron homeostasis.
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Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, 1345 Center Drive, Gainesville, FL, USA
| | - Yanping Zhang
- Interdisciplinary Center for Biotechnology Research (ICBR), Gene Expression and Genotyping, University of Florida, USA
| | - Shouguang Jin
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, USA
| | - Robert W Huigens
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, 1345 Center Drive, Gainesville, FL, USA
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30
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Assessment of in vivo versus in vitro biofilm formation of clinical methicillin-resistant Staphylococcus aureus isolates from endotracheal tubes. Sci Rep 2018; 8:11906. [PMID: 30093624 PMCID: PMC6085380 DOI: 10.1038/s41598-018-30494-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 07/31/2018] [Indexed: 12/31/2022] Open
Abstract
Our aim was to demonstrate that biofilm formation in a clinical strain of methicillin-resistant Staphylococcus aureus (MRSA) can be enhanced by environment exposure in an endotracheal tube (ETT) and to determine how it is affected by systemic treatment and atmospheric conditions. Second, we aimed to assess biofilm production dynamics after extubation. We prospectively analyzed 70 ETT samples obtained from pigs randomized to be untreated (controls, n = 20), or treated with vancomycin (n = 32) or linezolid (n = 18). A clinical MRSA strain (MRSA-in) was inoculated in pigs to create a pneumonia model, before treating with antibiotics. Tracheally intubated pigs with MRSA severe pneumonia, were mechanically ventilated for 69 ± 16 hours. All MRSA isolates retrieved from ETTs (ETT-MRSA) were tested for their in vitro biofilm production by microtiter plate assay. In vitro biofilm production of MRSA isolates was sequentially studied over the next 8 days post-extubation to assess biofilm capability dynamics over time. All experiments were performed under ambient air (O2) or ambient air supplemented with 5% CO2. We collected 52 ETT-MRSA isolates (placebo N = 19, linezolid N = 11, and vancomycin N = 22) that were clonally identical to the MRSA-in. Among the ETT-MRSA isolates, biofilm production more than doubled after extubation in 40% and 50% under 5% CO2 and O2, respectively. Systemic antibiotic treatment during intubation did not affect this outcome. Under both atmospheric conditions, biofilm production for MRSA-in was at least doubled for 9 ETT-MRSA isolates, and assessment of these showed that biofilm production decreased progressively over a 4-day period after extubation. In conclusion, a weak biofilm producer MRSA strain significantly enhances its biofilm production within an ETT, but it is influenced by the ETT environment rather than by the systemic treatment used during intubation or by the atmospheric conditions used for bacterial growth.
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31
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Ricciardi BF, Muthukrishnan G, Masters E, Ninomiya M, Lee CC, Schwarz EM. Staphylococcus aureus Evasion of Host Immunity in the Setting of Prosthetic Joint Infection: Biofilm and Beyond. Curr Rev Musculoskelet Med 2018; 11:389-400. [PMID: 29987645 DOI: 10.1007/s12178-018-9501-4] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
PURPOSE OF REVIEW The incidence of complications from prosthetic joint infection (PJI) is increasing, and treatment failure remains high. We review the current literature with a focus on Staphylococcus aureus pathogenesis and biofilm, as well as treatment challenges, and novel therapeutic strategies. RECENT FINDINGS S. aureus biofilm creates a favorable environment that increases antibiotic resistance, impairs host immunity, and increases tolerance to nutritional deprivation. Secreted proteins from bacterial cells within the biofilm and the quorum-sensing agr system contribute to immune evasion. Additional immunoevasive properties of S. aureus include the formation of staphylococcal abscess communities (SACs) and canalicular invasion. Novel approaches to target biofilm and increase resistance to implant colonization include novel antibiotic therapy, immunotherapy, and local implant treatments. Challenges remain given the diverse mechanisms developed by S. aureus to alter the host immune responses. Further understanding of these processes should provide novel therapeutic mechanisms to enhance eradication after PJI.
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Affiliation(s)
- Benjamin F Ricciardi
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester School of Medicine, 601 Elmwood Avenue, Box 665, Rochester, NY, 14642, USA
| | - Gowrishankar Muthukrishnan
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester School of Medicine, 601 Elmwood Avenue, Box 665, Rochester, NY, 14642, USA
| | - Elysia Masters
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester School of Medicine, 601 Elmwood Avenue, Box 665, Rochester, NY, 14642, USA
| | - Mark Ninomiya
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester School of Medicine, 601 Elmwood Avenue, Box 665, Rochester, NY, 14642, USA
| | - Charles C Lee
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester School of Medicine, 601 Elmwood Avenue, Box 665, Rochester, NY, 14642, USA
| | - Edward M Schwarz
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester School of Medicine, 601 Elmwood Avenue, Box 665, Rochester, NY, 14642, USA.
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32
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Juhlin A, Svensson S, Thomsen P, Trobos M. Staphylococcal biofilm gene expression on biomaterials - A methodological study. J Biomed Mater Res A 2017; 105:3400-3412. [PMID: 28782178 DOI: 10.1002/jbm.a.36171] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 08/01/2017] [Indexed: 01/02/2023]
Abstract
The combination of increased healthcare access, universal aging, and infallible therapy demands, synergistically drive the need for the development of biomaterial technologies that mitigate the challenge of biomaterial-associated infections (BAI). Staphylococcus epidermidis and Staphylococcus aureus account for the majority of BAI due to their ability to accumulate in adherent multilayered biofilm. This investigation details the development of gene expression assays to evaluate the genetic processes of attachment, accumulation, maturation, and dispersal phases of biofilms on biomaterials in vitro, while abiding by the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines. The biofilm formation of S. epidermidis on polyurethane (PU) central venous catheters and S. aureus on machined titanium (Ti) was examined in terms of gene expression at early and late time points. The results provided insight into how each stage of biofilm formation is orchestrated over time on these biomaterials in vitro. Furthermore, the results suggested that mechanical RNA extraction, organic solvents, elimination of genomic DNA, and preamplification are advisable strategies to implement for biofilm gene expression analysis. It is concluded that this method can be employed for the assessment of biofilm-biomaterial interactions at the molecular level. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3400-3412, 2017.
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Affiliation(s)
- Annika Juhlin
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
| | - Sara Svensson
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
| | - Peter Thomsen
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
| | - Margarita Trobos
- Department of Biomaterials, Sahlgrenska Academy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden.,BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, University of Gothenburg, P.O. Box 412, 40530, Gothenburg, Sweden
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Abstract
The staphylococci comprise a diverse genus of Gram-positive, nonmotile commensal organisms that inhabit the skin and mucous membranes of humans and other mammals. In general, staphylococci are benign members of the natural flora, but many species have the capacity to be opportunistic pathogens, mainly infecting individuals who have medical device implants or are otherwise immunocompromised. Staphylococcus aureus and Staphylococcus epidermidis are major sources of hospital-acquired infections and are the most common causes of surgical site infections and medical device-associated bloodstream infections. The ability of staphylococci to form biofilms in vivo makes them highly resistant to chemotherapeutics and leads to chronic diseases. These biofilm infections include osteomyelitis, endocarditis, medical device infections, and persistence in the cystic fibrosis lung. Here, we provide a comprehensive analysis of our current understanding of staphylococcal biofilm formation, with an emphasis on adhesins and regulation, while also addressing how staphylococcal biofilms interact with the immune system. On the whole, this review will provide a thorough picture of biofilm formation of the staphylococcus genus and how this mode of growth impacts the host.
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Gries CM, Kielian T. Staphylococcal Biofilms and Immune Polarization During Prosthetic Joint Infection. J Am Acad Orthop Surg 2017; 25 Suppl 1:S20-S24. [PMID: 27922945 PMCID: PMC5640443 DOI: 10.5435/jaaos-d-16-00636] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Staphylococcal species are a leading cause of community- and nosocomial-acquired infections, where the placement of foreign materials increases infection risk. Indwelling medical devices and prosthetic implants are targets for staphylococcal cell adherence and biofilm formation. Biofilm products actively suppress proinflammatory microbicidal responses, as evident by macrophage polarization toward an anti-inflammatory phenotype and the recruitment of myeloid-derived suppressor cells. With the rise in prosthetic hip and knee arthroplasty procedures, together with the recalcitrance of biofilm infections to antibiotic therapy, it is imperative to better understand the mechanism of crosstalk between biofilm-associated bacteria and host immune cells. This review describes the current understanding of how staphylococcal biofilms evade immune-mediated clearance to establish persistent infections. The findings described herein may facilitate the identification of novel treatments for these devastating biofilm-mediated infections.
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Affiliation(s)
- Casey M. Gries
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
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35
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Mirza YH, Tansey R, Sukeik M, Shaath M, Haddad FS. Biofilm and the Role of Antibiotics in the Treatment of Periprosthetic Hip and Knee Joint Infections. Open Orthop J 2016; 10:636-645. [PMID: 28484579 PMCID: PMC5398090 DOI: 10.2174/1874325001610010636] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 06/17/2016] [Accepted: 07/15/2016] [Indexed: 12/20/2022] Open
Abstract
An increasing demand for lower limb arthroplasty will lead to a proportionate increase in the need for revision surgery. A notable proportion of revision surgery is secondary to periprosthetic joint infections (PJI). Diagnosing and eradicating PJI can form a very difficult challenge. An important cause of PJI is the formation of a bacterial biofilm on the implant surface. Our review article seeks to describe biofilms; their definitions and formation, common causative bacteria, prophylactic and therapeutic antibiotic therapy.
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Affiliation(s)
- Yusuf H Mirza
- Department of Trauma and Orthopaedics, University College London Hospital, 235 Euston Road, NW1 2BU, London, United Kingdom
| | - Rosamond Tansey
- Department of Trauma and Orthopaedics, University College London Hospital, 235 Euston Road, NW1 2BU, London, United Kingdom
| | - Mohamed Sukeik
- Department of Trauma and Orthopaedics, Royal London Hospital, Whitechapel, London, E1 1BB, United Kingdom
| | - Mohammed Shaath
- Department of Trauma and Orthopaedics, North Manchester General Hospital, Delaunay's Road, Crumpsall, M8 5RB, United Kingdom
| | - Fares Sami Haddad
- Department of Trauma and Orthopaedics, University College London Hospital, 235 Euston Road, NW1 2BU, London, United Kingdom
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Azeredo J, Azevedo NF, Briandet R, Cerca N, Coenye T, Costa AR, Desvaux M, Di Bonaventura G, Hébraud M, Jaglic Z, Kačániová M, Knøchel S, Lourenço A, Mergulhão F, Meyer RL, Nychas G, Simões M, Tresse O, Sternberg C. Critical review on biofilm methods. Crit Rev Microbiol 2016; 43:313-351. [PMID: 27868469 DOI: 10.1080/1040841x.2016.1208146] [Citation(s) in RCA: 541] [Impact Index Per Article: 67.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research into the formation and elimination of biofilms is important for many disciplines. Several new methodologies have been recently developed for, or adapted to, biofilm studies that have contributed to deeper knowledge on biofilm physiology, structure and composition. In this review, traditional and cutting-edge methods to study biofilm biomass, viability, structure, composition and physiology are addressed. Moreover, as there is a lack of consensus among the diversity of techniques used to grow and study biofilms. This review intends to remedy this, by giving a critical perspective, highlighting the advantages and limitations of several methods. Accordingly, this review aims at helping scientists in finding the most appropriate and up-to-date methods to study their biofilms.
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Affiliation(s)
- Joana Azeredo
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Nuno F Azevedo
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Romain Briandet
- c Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay , Jouy-en-Josas , France
| | - Nuno Cerca
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Tom Coenye
- d Laboratory of Pharmaceutical Microbiology , Ghent University , Ghent , Belgium
| | - Ana Rita Costa
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Mickaël Desvaux
- e INRA Centre Auvergne-Rhône-Alpes , UR454 Microbiologie , Saint-Genès Champanelle , France
| | - Giovanni Di Bonaventura
- f Department of Medical, Oral, and Biotechnological Sciences, and Center of Excellence on Aging and Translational Medicine (CeSI-MeT) , "G. d'Annunzio" University of Chieti-Pescara , Chieti , Italy
| | - Michel Hébraud
- e INRA Centre Auvergne-Rhône-Alpes , UR454 Microbiologie , Saint-Genès Champanelle , France
| | - Zoran Jaglic
- g Department of Food and Feed Safety, Laboratory of Food Bacteriology , Veterinary Research Institute , Brno , Czech Republic
| | - Miroslava Kačániová
- h Department of Microbiology, Faculty of Biotechnology and Food Sciences , Slovak University of Agriculture in Nitra , Nitra , Slovakia
| | - Susanne Knøchel
- i Department of Food Science (FOOD) , University of Copenhagen , Frederiksberg C , Denmark
| | - Anália Lourenço
- j Department of Computer Science , University of Vigo , Ourense , Spain
| | - Filipe Mergulhão
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Rikke Louise Meyer
- k Aarhus University, Interdisciplinary Nanoscience Center (iNANO) , Aarhus , Denmark
| | - George Nychas
- l Agricultural University of Athens, Lab of Microbiology and Biotechnology of Foods , Athens , Greece
| | - Manuel Simões
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Odile Tresse
- m LUNAM Université, Oniris, SECALIM UMR1024 INRA , Université de Nantes , Nantes , France
| | - Claus Sternberg
- n Department of Biotechnology and Biomedicine , Technical University of Denmark , Lyngby, Denmark
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Beltrame CO, Côrtes MF, Bandeira PT, Figueiredo AMS. Optimization of the RNeasy Mini Kit to obtain high-quality total RNA from sessile cells of Staphylococcus aureus. ACTA ACUST UNITED AC 2016; 48:1071-6. [PMID: 26517334 PMCID: PMC4661022 DOI: 10.1590/1414-431x20154734] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 07/23/2015] [Indexed: 12/20/2022]
Abstract
Biofilm formed by Staphylococcus aureus is considered an important
virulence trait in the pathogenesis of infections associated with implantable medical
devices. Gene expression analyses are important strategies for determining the
mechanisms involved in production and regulation of biofilm. Obtaining intact RNA
preparations is the first and most critical step for these studies. In this article,
we describe an optimized protocol for obtaining total RNA from sessile cells of
S. aureus using the RNeasy Mini Kit. This method essentially
consists of a few steps, as follows: 1) addition of acetone-ethanol to sessile cells,
2) lysis with lysostaphin at 37°C/10 min, 3) vigorous mixing, 4) three cycles of
freezing and thawing, and 5) purification of the lysate in the RNeasy column. This
simple pre-kit procedure yields high-quality total RNA from planktonic and sessile
cells of S. aureus.
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Affiliation(s)
- C O Beltrame
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - M F Côrtes
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - P T Bandeira
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - A M S Figueiredo
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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Cui B, Smooker PM, Rouch DA, Deighton MA. Selection of suitable reference genes for gene expression studies in Staphylococcus capitis during growth under erythromycin stress. Mol Genet Genomics 2016; 291:1795-811. [PMID: 27000656 DOI: 10.1007/s00438-016-1197-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 03/05/2016] [Indexed: 11/28/2022]
Abstract
Accurate and reproducible measurement of gene transcription requires appropriate reference genes, which are stably expressed under different experimental conditions to provide normalization. Staphylococcus capitis is a human pathogen that produces biofilm under stress, such as imposed by antimicrobial agents. In this study, a set of five commonly used staphylococcal reference genes (gyrB, sodA, recA, tuf and rpoB) were systematically evaluated in two clinical isolates of Staphylococcus capitis (S. capitis subspecies urealyticus and capitis, respectively) under erythromycin stress in mid-log and stationary phases. Two public software programs (geNorm and NormFinder) and two manual calculation methods, reference residue normalization (RRN) and relative quantitative (RQ), were applied. The potential reference genes selected by the four algorithms were further validated by comparing the expression of a well-studied biofilm gene (icaA) with phenotypic biofilm formation in S. capitis under four different experimental conditions. The four methods differed considerably in their ability to predict the most suitable reference gene or gene combination for comparing icaA expression under different conditions. Under the conditions used here, the RQ method provided better selection of reference genes than the other three algorithms; however, this finding needs to be confirmed with a larger number of isolates. This study reinforces the need to assess the stability of reference genes for analysis of target gene expression under different conditions and the use of more than one algorithm in such studies. Although this work was conducted using a specific human pathogen, it emphasizes the importance of selecting suitable reference genes for accurate normalization of gene expression more generally.
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Affiliation(s)
- Bintao Cui
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, VIC, 3083, Australia
| | - Peter M Smooker
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, VIC, 3083, Australia
| | - Duncan A Rouch
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, VIC, 3083, Australia
| | - Margaret A Deighton
- School of Applied Sciences, RMIT University, Plenty Road, Bundoora, VIC, 3083, Australia.
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Omics Approaches for the Study of Adaptive Immunity to Staphylococcus aureus and the Selection of Vaccine Candidates. Proteomes 2016; 4:proteomes4010011. [PMID: 28248221 PMCID: PMC5217363 DOI: 10.3390/proteomes4010011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 02/05/2016] [Accepted: 03/01/2016] [Indexed: 01/20/2023] Open
Abstract
Staphylococcus aureus is a dangerous pathogen both in hospitals and in the community. Due to the crisis of antibiotic resistance, there is an urgent need for new strategies to combat S. aureus infections, such as vaccination. Increasing our knowledge about the mechanisms of protection will be key for the successful prevention or treatment of S. aureus invasion. Omics technologies generate a comprehensive picture of the physiological and pathophysiological processes within cells, tissues, organs, organisms and even populations. This review provides an overview of the contribution of genomics, transcriptomics, proteomics, metabolomics and immunoproteomics to the current understanding of S. aureus‑host interaction, with a focus on the adaptive immune response to the microorganism. While antibody responses during colonization and infection have been analyzed in detail using immunoproteomics, the full potential of omics technologies has not been tapped yet in terms of T-cells. Omics technologies promise to speed up vaccine development by enabling reverse vaccinology approaches. In consequence, omics technologies are powerful tools for deepening our understanding of the “superbug” S. aureus and for improving its control.
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Genetic Screen Reveals the Role of Purine Metabolism in Staphylococcus aureus Persistence to Rifampicin. Antibiotics (Basel) 2015; 4:627-42. [PMID: 27025643 PMCID: PMC4790316 DOI: 10.3390/antibiotics4040627] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/20/2015] [Accepted: 11/27/2015] [Indexed: 12/02/2022] Open
Abstract
Chronic infections with Staphylococcus aureus such as septicemia, osteomyelitis, endocarditis, and biofilm infections are difficult to treat because of persisters. Despite many efforts in understanding bacterial persistence, the mechanisms of persister formation in S. aureus remain elusive. Here, we performed a genome-wide screen of a transposon mutant library to study the molecular mechanisms involved in persistence of community-acquired S. aureus. Screening of the library for mutants defective in persistence or tolerance to rifampicin revealed many genes involved in metabolic pathways that are important for antibiotic persistence. In particular, the identified mutants belonged to metabolic pathways involved in carbohydrate, amino acid, lipid, vitamin and purine biosynthesis. Five mutants played a role in purine biosynthesis and two mutants, purB, an adenylosuccinate lyase, and purM, a phosphoribosylaminoimidazole synthetase, were selected for further confirmation. Mutants purB and purM showed defective persistence compared to the parental strain USA300 in multiple stress conditions including various antibiotics, low pH, and heat stress. The defect in persistence was restored by complementation with the wildtype purB and purM gene in the respective mutants. These findings provide new insights into the mechanisms of persistence in S. aureus and provide novel therapeutic targets for developing more effective treatment for persistent infections due to S. aureus.
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Bhattacharya M, Wozniak DJ, Stoodley P, Hall-Stoodley L. Prevention and treatment of Staphylococcus aureus biofilms. Expert Rev Anti Infect Ther 2015; 13:1499-516. [PMID: 26646248 DOI: 10.1586/14787210.2015.1100533] [Citation(s) in RCA: 168] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
S. aureus colonizes both artificial and tissue surfaces in humans causing chronic persistent infections that are difficult to cure. It is a notorious pathogen due to its antibiotic recalcitrance and phenotypic adaptability, both of which are facilitated by its ability to develop biofilms. S. aureus biofilms challenge conventional anti-infective approaches, most notably antibiotic therapy. Therefore there is an unmet need to develop and include parallel approaches that target S. aureus biofilm infections. This review discusses two broad anti-infective strategies: (1) preventative approaches (anti-biofilm surface coatings, the inclusion of biofilm-specific vaccine antigens); and (2) approaches aimed at eradicating established S. aureus biofilms, particularly those associated with implant infections. Advances in understanding the distinct nature of S. aureus biofilm development and pathogenesis have led to growing optimism in S. aureus biofilm targeted anti-infective strategies. Further research is needed however, to see the successful administration and validation of these approaches to the diverse types of infections caused by S. aureus biofilms from multiple clinical strains.
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Affiliation(s)
- Mohini Bhattacharya
- a Department of Microbiology , The Ohio State University , Columbus , OH , USA
| | - Daniel J Wozniak
- a Department of Microbiology , The Ohio State University , Columbus , OH , USA.,b Department of Microbial Infection and Immunity , The Ohio State University College of Medicine , Columbus , OH , USA.,c The Center for Microbial Interface Biology, The Ohio State University , Columbus , OH , USA
| | - Paul Stoodley
- b Department of Microbial Infection and Immunity , The Ohio State University College of Medicine , Columbus , OH , USA.,c The Center for Microbial Interface Biology, The Ohio State University , Columbus , OH , USA.,d Department of Orthopedics , The Ohio State University College of Medicine , Columbus , OH , USA.,e Department of Engineering Sciences, National Centre for Advanced Tribology at Southampton (nCATS) , University of Southampton , Southampton , UK
| | - Luanne Hall-Stoodley
- b Department of Microbial Infection and Immunity , The Ohio State University College of Medicine , Columbus , OH , USA.,c The Center for Microbial Interface Biology, The Ohio State University , Columbus , OH , USA
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42
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Anti-inflammatory effect of thalidomide dithiocarbamate and dithioate analogs. Chem Biol Interact 2015; 238:74-81. [DOI: 10.1016/j.cbi.2015.05.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 05/12/2015] [Accepted: 05/29/2015] [Indexed: 12/16/2022]
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Dynamics of the Streptococcus gordonii Transcriptome in Response to Medium, Salivary α-Amylase, and Starch. Appl Environ Microbiol 2015; 81:5363-74. [PMID: 26025889 DOI: 10.1128/aem.01221-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 05/22/2015] [Indexed: 01/14/2023] Open
Abstract
Streptococcus gordonii, a primary colonizer of the tooth surface, interacts with salivary α-amylase via amylase-binding protein A (AbpA). This enzyme hydrolyzes starch to glucose, maltose, and maltodextrins that can be utilized by various oral bacteria for nutrition. Microarray studies demonstrated that AbpA modulates gene expression in response to amylase, suggesting that the amylase-streptococcal interaction may function in ways other than nutrition. The goal of this study was to explore the role of AbpA in gene regulation through comparative transcriptional profiling of wild-type KS1 and AbpA(-) mutant KS1ΩabpA under various environmental conditions. A portion of the total RNA isolated from mid-log-phase cells grown in 5% CO2 in (i) complex medium with or without amylase, (ii) defined medium (DM) containing 0.8% glucose with/without amylase, and (iii) DM containing 0.2% glucose and amylase with or without starch was reverse transcribed to cDNA and the rest used for RNA sequencing. Changes in the expression of selected genes were validated by quantitative reverse transcription-PCR. Maltodextrin-associated genes, fatty acid synthesis genes and competence genes were differentially expressed in a medium-dependent manner. Genes in another cluster containing a putative histidine kinase/response regulator, peptide methionine sulfoxide reductase, thioredoxin protein, lipoprotein, and cytochrome c-type protein were downregulated in KS1ΩabpA under all of the environmental conditions tested. Thus, AbpA appears to modulate genes associated with maltodextrin utilization/transport and fatty acid synthesis. Importantly, in all growth conditions AbpA was associated with increased expression of a potential two-component signaling system associated with genes involved in reducing oxidative stress, suggesting a role in signal transduction and stress tolerance.
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Chung JW, Greenwood-Quaintance KE, Karau MJ, Tilahun A, Khaleghi SR, Chowdhary VR, David CS, Patel R, Rajagopalan G. Superantigens produced by catheter-associated Staphylococcus aureus elicit systemic inflammatory disease in the absence of bacteremia. J Leukoc Biol 2015; 98:271-81. [PMID: 25979434 DOI: 10.1189/jlb.4a1214-577rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 04/17/2015] [Indexed: 11/24/2022] Open
Abstract
SAgs, produced by Staphylococcus aureus, play a major role in the pathogenesis of invasive staphylococcal diseases by inducing potent activation of the immune system. However, the role of SAgs, produced by S. aureus, associated with indwelling devices or tissues, are not known. Given the prevalence of device-associated infection with toxigenic S. aureus in clinical settings and the potency of SAgs, we hypothesized that continuous exposure to SAgs produced by catheter-associated S. aureus could have systemic consequences. To investigate these effects, we established a murine in vivo catheter colonization model. One centimeter long intravenous catheters were colonized with a clinical S. aureus isolate producing SAgs or isogenic S. aureus strains, capable or incapable of producing SAg. Catheters were subcutaneously implanted in age-matched HLA-DR3, B6, and AE(o) mice lacking MHC class II molecules and euthanized 7 d later. There was no evidence of systemic infection. However, in HLA-DR3 transgenic mice, which respond robustly to SSAgs, the SSAg-producing, but not the nonproducing strains, caused a transient increase in serum cytokine levels and a protracted expansion of splenic CD4(+) T cells expressing SSAg-reactive TCR Vβ8. Lungs, livers, and kidneys from these mice showed infiltration with CD4(+) and CD11b(+) cells. These findings were absent in B6 and AE(o) mice, which are known to respond poorly to SSAgs. Overall, our novel findings suggest that systemic immune activation elicited by SAgs, produced by S. aureus colonizing foreign bodies, could have clinical consequences in humans.
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Affiliation(s)
- Jin-Won Chung
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Kerryl E Greenwood-Quaintance
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Melissa J Karau
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Ashenafi Tilahun
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Shahryar Rostamkolaei Khaleghi
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Vaidehi R Chowdhary
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Chella S David
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Robin Patel
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
| | - Govindarajan Rajagopalan
- *Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Divisions of Infectious Diseases and Rheumatology, Department of Medicine, and Department of Immunology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA; and Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, Republic of Korea
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Rafii F, Hart ME. Antimicrobial resistance in clinically important biofilms. World J Pharmacol 2015; 4:31-46. [DOI: 10.5497/wjp.v4.i1.31] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 10/22/2014] [Accepted: 12/17/2014] [Indexed: 02/06/2023] Open
Abstract
A biofilm contains a consortium of cohesive bacterial cells forming a complex structure that is a sedentary, but dynamic, community. Biofilms adhere on biotic and abiotic surfaces, including the surfaces of practically all medical devices. Biofilms are reported to be responsible for approximately 60% of nosocomial infections due to implanted medical devices, such as intravenous catheters, and they also cause other foreign-body infections and chronic infections. The presence of biofilm on a medical device may result in the infection of surrounding tissues and failure of the device, necessitating the removal and replacement of the device. Bacteria from biofilms formed on medical devices may be released and disperse, with the potential for the formation of new biofilms in other locations and the development of a systemic infection. Regardless of their location, bacteria in biofilms are tolerant of the activities of the immune system, antimicrobial agents, and antiseptics. Concentrations of antimicrobial agents sufficient to eradicate planktonic cells have no effect on the same microorganism in a biofilm. Depending on the microbial consortium or component of the biofilm that is involved, various combinations of factors have been suggested to explain the recalcitrant nature of biofilms toward killing by antibiotics. In this mini-review, some of the factors contributing to antimicrobial resistance in biofilms are discussed.
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46
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Foreign Body Infection Models to Study Host-Pathogen Response and Antimicrobial Tolerance of Bacterial Biofilm. Antibiotics (Basel) 2014; 3:378-97. [PMID: 27025752 PMCID: PMC4790362 DOI: 10.3390/antibiotics3030378] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 07/01/2014] [Accepted: 08/06/2014] [Indexed: 12/13/2022] Open
Abstract
The number of implanted medical devices is steadily increasing and has become an effective intervention improving life quality, but still carries the risk of infection. These infections are mainly caused by biofilm-forming staphylococci that are difficult to treat due to the decreased susceptibility to both antibiotics and host defense mechanisms. To understand the particular pathogenesis and treatment tolerance of implant-associated infection (IAI) animal models that closely resemble human disease are needed. Applications of the tissue cage and catheter abscess foreign body infection models in the mouse will be discussed herein. Both models allow the investigation of biofilm and virulence of various bacterial species and a comprehensive insight into the host response at the same time. They have also been proven to serve as very suitable tools to study the anti-adhesive and anti-infective efficacy of different biomaterial coatings. The tissue cage model can additionally be used to determine pharmacokinetics, efficacy and cytotoxicity of antimicrobial compounds as the tissue cage fluid can be aspirated repeatedly without the need to sacrifice the animal. Moreover, with the advance in innovative imaging systems in rodents, these models may offer new diagnostic measures of infection. In summary, animal foreign body infection models are important tools in the development of new antimicrobials against IAI and can help to elucidate the complex interactions between bacteria, the host immune system, and prosthetic materials.
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Gutierrez-Murgas Y, Snowden JN. Ventricular shunt infections: immunopathogenesis and clinical management. J Neuroimmunol 2014; 276:1-8. [PMID: 25156073 DOI: 10.1016/j.jneuroim.2014.08.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/17/2014] [Accepted: 08/06/2014] [Indexed: 12/22/2022]
Abstract
Ventricular shunts are the most common neurosurgical procedure performed in the United States. This hydrocephalus treatment is often complicated by infection of the device with biofilm-forming bacteria. In this review, we discuss the pathogenesis of shunt infection, as well as the implications of the biofilm formation on treatment and prevention of these infections. Many questions remain, including the contribution of glia and the impact of inflammation on developmental outcomes following infection. Immune responses within the CNS must be carefully regulated to contain infection while minimizing bystander damage; further study is needed to design optimal treatment strategies for these patients.
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Affiliation(s)
- Yenis Gutierrez-Murgas
- Department of Pathology & Microbiology, University of Nebraska Medical Center, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, USA.
| | - Jessica N Snowden
- Department of Pathology & Microbiology, University of Nebraska Medical Center, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, USA; Department of Pediatrics, University of Nebraska Medical Center, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, USA.
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48
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Heim CE, Vidlak D, Scherr TD, Kozel JA, Holzapfel M, Muirhead DE, Kielian T. Myeloid-derived suppressor cells contribute to Staphylococcus aureus orthopedic biofilm infection. THE JOURNAL OF IMMUNOLOGY 2014; 192:3778-92. [PMID: 24646737 DOI: 10.4049/jimmunol.1303408] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature monocytes and granulocytes that are potent inhibitors of T cell activation. A role for MDSCs in bacterial infections has only recently emerged, and nothing is known about MDSC function in the context of Staphylococcus aureus infection. Because S. aureus biofilms are capable of subverting immune-mediated clearance, we examined whether MDSCs could play a role in this process. CD11b(+)Gr-1(+) MDSCs represented the main cellular infiltrate during S. aureus orthopedic biofilm infection, accounting for >75% of the CD45+ population. Biofilm-associated MDSCs inhibited T cell proliferation and cytokine production, which correlated with a paucity of T cell infiltrates at the infection site. Analysis of FACS-purified MDSCs recovered from S. aureus biofilms revealed increased arginase-1, inducible NO synthase, and IL-10 expression, key mediators of MDSC suppressive activity. Targeted depletion of MDSCs and neutrophils using the mAb 1A8 (anti-Ly6G) improved bacterial clearance by enhancing the intrinsic proinflammatory attributes of infiltrating monocytes and macrophages. Furthermore, the ability of monocytes/macrophages to promote biofilm clearance in the absence of MDSC action was revealed with RB6-C85 (anti-Gr-1 or anti-Ly6G/Ly6C) administration, which resulted in significantly increased S. aureus burdens both locally and in the periphery, because effector Ly 6C monocytes and, by extension, mature macrophages were also depleted. Collectively, these results demonstrate that MDSCs are key contributors to the chronicity of S. aureus biofilm infection, as their immunosuppressive function prevents monocyte/macrophage proinflammatory activity, which facilitates biofilm persistence.
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Affiliation(s)
- Cortney E Heim
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
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Scherr TD, Heim CE, Morrison JM, Kielian T. Hiding in Plain Sight: Interplay between Staphylococcal Biofilms and Host Immunity. Front Immunol 2014; 5:37. [PMID: 24550921 PMCID: PMC3913997 DOI: 10.3389/fimmu.2014.00037] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 01/22/2014] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus and Staphylococcus epidermidis are notable for their propensity to form biofilms on implanted medical devices. Staphylococcal biofilm infections are typified by their recalcitrance to antibiotics and ability to circumvent host immune-mediated clearance, resulting in the establishment of chronic infections that are often recurrent in nature. Indeed, the immunomodulatory lifestyle of biofilms seemingly shapes the host immune response to ensure biofilm engraftment and persistence in an immune competent host. Here, we provide a brief review of the mechanisms whereby S. aureus and S. epidermidis biofilms manipulate host–pathogen interactions and discuss the concept of microenvironment maintenance in infectious outcomes, as well as speculate how these findings pertain to the challenges of staphylococcal vaccine development.
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Affiliation(s)
- Tyler D Scherr
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
| | - Cortney E Heim
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
| | - John M Morrison
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
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