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Hospach T, Kallinich T, Martin L, V Kalle T, Reichert F, Girschick HJ, Hedrich CM. [Arthritis and osteomyelitis in childhood and adolescence-Bacterial and nonbacterial]. Z Rheumatol 2024:10.1007/s00393-024-01504-z. [PMID: 38653784 DOI: 10.1007/s00393-024-01504-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/29/2024] [Indexed: 04/25/2024]
Abstract
Bacterial arthritis and osteomyelitis are usually acute diseases, which in this way differ from the often insidious course of nonbacterial osteomyelitis; however, there is often an overlap both in less acute courses of bacterial illnesses and also in nonbacterial osteitis. The overlapping clinical phenomena can be explained by similar pathophysiological processes. In bacteria-related illnesses the identification of the pathogen and empirical or targeted anti-infectious treatment are prioritized, whereas no triggering agent is known for nonbacterial diseases. The diagnostics are based on the exclusion of differential diagnoses, clinical scores and magnetic resonance imaging (MRI). An activity-adapted anti-inflammatory treatment is indicated.
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Affiliation(s)
- T Hospach
- Zentrum für Pädiatrische Rheumatologie, Olgahospital, Klinikum Stuttgart (ZEPRAS), Kriegsbergstr 62, 70176, Stuttgart, Deutschland.
| | - T Kallinich
- Klinik für Pädiatrie m.S. Pneumologie, Immunologie und Intensivmedizin, Charité, Universitätsmedizin Berlin, Berlin, Deutschland
| | - L Martin
- Klinik für Pädiatrie m.S. Pneumologie, Immunologie und Intensivmedizin, Charité, Universitätsmedizin Berlin, Berlin, Deutschland
| | - T V Kalle
- Radiologisches Institut, Olgahospital, Klinikum Stuttgart, Stuttgart, Deutschland
| | - F Reichert
- Pädiatrische Infektiologie, Olgahospital, Klinikum Stuttgart, Stuttgart, Deutschland
| | - H J Girschick
- Vivantes Klinikum Friedrichshain, Berlin, Deutschland
| | - C M Hedrich
- Department of Women's and Children's Health, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, Großbritannien
- Department of Rheumatology, Alder Hey Children's NHS Foundation Trust, Liverpool, Großbritannien
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Kadirvelu L, Sivaramalingam SS, Jothivel D, Chithiraiselvan DD, Karaiyagowder Govindarajan D, Kandaswamy K. A review on antimicrobial strategies in mitigating biofilm-associated infections on medical implants. CURRENT RESEARCH IN MICROBIAL SCIENCES 2024; 6:100231. [PMID: 38510214 PMCID: PMC10951465 DOI: 10.1016/j.crmicr.2024.100231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024] Open
Abstract
Biomedical implants are crucial in providing support and functionality to patients with missing or defective body parts. However, implants carry an inherent risk of bacterial infections that are biofilm-associated and lead to significant complications. These infections often result in implant failure, requiring replacement by surgical restoration. Given these complications, it is crucial to study the biofilm formation mechanism on various biomedical implants that will help prevent implant failures. Therefore, this comprehensive review explores various types of implants (e.g., dental implant, orthopedic implant, tracheal stent, breast implant, central venous catheter, cochlear implant, urinary catheter, intraocular lens, and heart valve) and medical devices (hemodialyzer and pacemaker) in use. In addition, the mechanism of biofilm formation on those implants, and their pathogenesis were discussed. Furthermore, this article critically reviews various approaches in combating implant-associated infections, with a special emphasis on novel non-antibiotic alternatives to mitigate biofilm infections.
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Affiliation(s)
- Lohita Kadirvelu
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | - Sowmiya Sri Sivaramalingam
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | - Deepsikha Jothivel
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | - Dhivia Dharshika Chithiraiselvan
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
| | | | - Kumaravel Kandaswamy
- Research Center for Excellence in Microscopy, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, 641049, Tamil Nadu, India
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Li J, Li H, Bi S, Sun Y, Gu F, Yu T. Shock wave assisted intracellular delivery of antibiotics against bone infection with Staphylococcus aureus via P2X7 receptors. J Orthop Translat 2024; 45:10-23. [PMID: 38434180 PMCID: PMC10904912 DOI: 10.1016/j.jot.2023.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 10/20/2023] [Indexed: 03/05/2024] Open
Abstract
Background Treatment of chronic osteomyelitis (bone infection) remains a clinical challenge; in particular, it requires enhanced delivery of antibiotic drugs for the treatment of intracellular Staphylococcus aureus (S. aureus), which prevents infection recurrence and resistance. Previous studies have found that noninvasive shock waves used to treat musculoskeletal diseases can alter cell permeability, however, it is unclear whether shock waves alter cell membrane permeability in chronic osteomyelitis. Furthermore, it remains unknown whether such changes in permeability promote the entry of antibiotics into osteoblasts to exert antibacterial effects. Methods In our study, trypan blue staining was used to determine the shock wave parameters that had no obvious damage to the osteoblast model; the effect of shocks waves on the cell membrane permeability of osteoblast model was detected by BODIPY®FL vancomycin; high performance liquid chromatography-mass spectrometry (HLPC-MS) was used to detect the effect of shock wave on the entry of antibiotics into the osteoblast model; plate colony counting method was used to detect the clearance effect of shock wave assisted antibiotics on S. aureus in the osteoblast model. To explore the mechanism, the effect of different pulses of shock waves on S. aureus was examined by plate colony counting method, besides, P2X7 receptor in osteoblast was detected by immunofluorescence and the extracellular ATP levels was detected. Furthermore, the effect of P2X7 receptor antagonists KN-62 or A740003 on the intracellular antibacterial activity of shock-assisted antibiotics was observed. Then, we used S. aureus to establish a rat model of chronic tibial osteomyelitis and investigated the efficacy and safety of shock-wave assisted antibiotics in the treatment of chronic osteomyelitis in rats. Results The viability of the osteoblast models of intracellular S. aureus infection was not significantly affected by the application of up to 400 shock wave pulses at 0.21 mJ/mm2. Surprisingly, the delivery of BODIPY®FL vancomycin to osteoblast model cells was markedly enhanced by this shock wave treatment. Furthermore, the shock wave therapy increased the delivery of hydrophilic antibiotics (vancomycin and cefuroxime sodium), but not lipophilic antibiotics (rifampicin and levofloxacin), which improved the intracellular antibacterial effect. Afterwards, we discovered that shock wave treatment increased the extracellular concentration of ATP (the P2X7 receptor activator), while KN-62 or A740003, a P2X7 receptor inhibitor, decreased intracellular antibacterial activity. We then found that 0.1 mL of 1 × 1011 CFU/mL ATCC25923 S. aureus was suitable for modeling chronic osteomyelitis in rats. Besides, the shock wave-assisted vancomycin treatment with the strongest antibacterial and osteogenic effects among the tested treatments was confirmed in vivo by imaging examination, microbiological cultures, and histopathology, with favorable safety. Conclusions Our results suggest that shock waves can promote the entry of antibiotics into osteoblasts for antibacteria by changing the cell membrane permeability in a P2X7 receptor-dependent manner. Besides, considering antibacterial and osteogenic efficiency and a high degree of safety in rat osteomyelitis model, shock wave-assisted vancomycin treatment may thus represent a possible adjuvant therapy for chronic osteomyelitis.
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Affiliation(s)
- Jiangbi Li
- Department of Orthopedics , Orthopaedic Center, The First Hospital of Jilin University, Changchun, Jilin, China
- Department of Orthopaedics, Yunnan Cancer Hospital, The Third Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Haixia Li
- Department of Neurology, The Affiliated Hospital of Kunming University of Science and Technology, the First People's Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Songqi Bi
- Department of Orthopedics , Orthopaedic Center, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Yang Sun
- Department of Orthopedics , Orthopaedic Center, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Feng Gu
- Department of Orthopedics , The Second Hospital of Jilin University, Changchun, Jilin, China
| | - Tiecheng Yu
- Department of Orthopedics , Orthopaedic Center, The First Hospital of Jilin University, Changchun, Jilin, China
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Bertrand BP, Shinde D, Thomas VC, Whiteley M, Ibberson CB, Kielian T. Metabolic diversity of human macrophages: potential influence on Staphylococcus aureus intracellular survival. Infect Immun 2024; 92:e0047423. [PMID: 38179975 PMCID: PMC10863412 DOI: 10.1128/iai.00474-23] [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: 11/14/2023] [Accepted: 12/04/2023] [Indexed: 01/06/2024] Open
Abstract
Staphylococcus aureus is a leading cause of medical device-associated biofilm infections. This is influenced by the ability of S. aureus biofilm to evade the host immune response, which is partially driven by the anti-inflammatory cytokine interleukin-10 (IL-10). Here, we show that treatment of human monocyte-derived macrophages (HMDMs) with IL-10 enhanced biofilm formation, suggesting that macrophage anti-inflammatory programming likely plays an important role during the transition from planktonic to biofilm growth. To identify S. aureus genes that were important for intracellular survival in HMDMs and how this was affected by IL-10, transposon sequencing was performed. The size of the S. aureus essential genome was similar between unstimulated HMDMs and the outgrowth control (18.5% vs 18.4%, respectively, with 54.4% overlap) but increased to 22.5% in IL-10-treated macrophages, suggesting that macrophage polarization status exerts differential pressure on S. aureus. Essential genes for S. aureus survival within IL-10-polarized HMDMs were dominated by negative regulatory pathways, including nitrogen and RNA metabolism, whereas S. aureus essential genes within untreated HMDMs were enriched in biosynthetic pathways such as purine and pyrimidine biosynthesis. To explore how IL-10 altered the macrophage intracellular metabolome, targeted metabolomics was performed on HMDMs from six individual donors. IL-10 treatment led to conserved alterations in distinct metabolites that were increased (dihydroxyacetone phosphate, glyceraldehyde-3-phosphate, and acetyl-CoA) or reduced (fructose-6-phosphate, aspartic acid, and ornithine) across donors, whereas other metabolites were variable. Collectively, these findings highlight an important aspect of population-level heterogeneity in human macrophage responsiveness that should be considered when translating results to a patient population.IMPORTANCEOne mechanism that Staphylococcus aureus biofilm elicits in the host to facilitate infection persistence is the production of the anti-inflammatory cytokine interleukin-10 (IL-10). Here, we show that exposure of human monocyte-derived macrophages (HMDMs) to IL-10 promotes S. aureus biofilm formation and programs intracellular bacteria to favor catabolic pathways. Examination of intracellular metabolites in HMDMs revealed heterogeneity between donors that may explain the observed variability in essential genes for S. aureus survival based on nutrient availability for bacteria within the intracellular compartment. Collectively, these studies provide novel insights into how IL-10 polarization affects S. aureus intracellular survival in HMDMs and the importance of considering macrophage heterogeneity between human donors as a variable when examining effector mechanisms.
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Affiliation(s)
- Blake P. Bertrand
- Department of Pathology, Microbiology, and Immunology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Dhananjay Shinde
- Department of Pathology, Microbiology, and Immunology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Vinai C. Thomas
- Department of Pathology, Microbiology, and Immunology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Marvin Whiteley
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Carolyn B. Ibberson
- School of Biological Sciences, University of Oklahoma, Norman, Oklahoma, USA
| | - Tammy Kielian
- Department of Pathology, Microbiology, and Immunology, University of Nebraska Medical Center, Omaha, Nebraska, USA
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Kelly JJ, Dalesandro BE, Liu Z, Chordia MD, Ongwae GM, Pires MM. Measurement of Accumulation of Antibiotics to Staphylococcus aureus in Phagosomes of Live Macrophages. Angew Chem Int Ed Engl 2024; 63:e202313870. [PMID: 38051128 PMCID: PMC10799677 DOI: 10.1002/anie.202313870] [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: 10/16/2023] [Revised: 11/28/2023] [Accepted: 12/05/2023] [Indexed: 12/07/2023]
Abstract
Staphylococcus aureus (S. aureus) has evolved the ability to persist after uptake into host immune cells. This intracellular niche enables S. aureus to potentially escape host immune responses and survive the lethal actions of antibiotics. While the elevated tolerance of S. aureus to small-molecule antibiotics is likely to be multifactorial, we pose that there may be contributions related to permeation of antibiotics into phagocytic vacuoles, which would require translocation across two mammalian bilayers. To empirically test this, we adapted our recently developed permeability assay to determine the accumulation of FDA-approved antibiotics into phagocytic vacuoles of live macrophages. Bioorthogonal reactive handles were metabolically anchored within the surface of S. aureus, and complementary tags were chemically added to antibiotics. Following phagocytosis of tagged S. aureus cells, we were able to specifically analyze the arrival of antibiotics within the phagosomes of infected macrophages. Our findings enabled the determination of permeability differences between extra- and intracellular S. aureus, thus providing a roadmap to dissect the contribution of antibiotic permeability to intracellular pathogens.
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Affiliation(s)
| | | | - Zichen Liu
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA
| | - Mahendra D. Chordia
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA
| | - George M. Ongwae
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA
| | - Marcos M. Pires
- Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA
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6
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Kelly JJ, Dalesandro BE, Liu Z, Chordia MD, Ongwae GM, Pires MM. Measurement of Accumulation of Antibiotics to Staphylococcus aureus in Phagosomes of Live Macrophages. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.13.528196. [PMID: 36824967 PMCID: PMC9949086 DOI: 10.1101/2023.02.13.528196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Staphylococcus aureus ( S. aureus ) has evolved the ability to persist after uptake into host immune cells. This intracellular niche enables S. aureus to potentially escape host immune responses and survive the lethal actions of antibiotics. While the elevated tolerance of S. aureus to small-molecule antibiotics is likely to be multifactorial, we pose that there may be contributions related to permeation of antibiotics into phagocytic vacuoles, which would require translocation across two mammalian bilayers. To empirically test this, we adapted our recently developed permeability assay to determine the accumulation of FDA-approved antibiotics into phagocytic vacuoles of live macrophages. Bioorthogonal reactive handles were metabolically anchored within the surface of S. aureus, and complementary tags were chemically added to antibiotics. Following phagocytosis of tagged S. aureus cells, we were able to specifically analyze the arrival of antibiotics within the phagosomes of infected macrophages. Our findings enabled the determination of permeability differences between extra- and intracellular S. aureus , thus providing a roadmap to dissect the contribution of antibiotic permeability to intracellular pathogens.
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Chen Z, Xie Z, Han M, Jin Q, Li Z, Zhai Y, Zhang M, Hu G, Zhang H. Global Transcriptomic Study of Circular-RNA Expression Profile in Osteoclasts Infected by Intracellular Staphylococcus aureus. Infect Immun 2023; 91:e0035722. [PMID: 37212691 PMCID: PMC10269070 DOI: 10.1128/iai.00357-22] [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: 04/22/2023] [Accepted: 05/01/2023] [Indexed: 05/23/2023] Open
Abstract
Osteomyelitis is difficult to cure, and the rapidly rising morbidity is a thorny problem accompanied by a large number of joint replacement applications. Staphylococcus aureus is the main pathogen of osteomyelitis. Circular RNAs (circRNAs), as emerging noncoding RNAs, play important roles in multiple physiopathological processes which could provide novel insights into osteomyelitis. However, little is known about the roles of circRNAs in the pathogenesis of osteomyelitis. Osteoclasts, considered bone sentinels, are the resident macrophages in bone and may play the immune defense roles in osteomyelitis. It has been reported that S. aureus can survive in osteoclasts, but the function of osteoclast circRNAs in response to intracellular S. aureus infection remains unclear. In this study, we investigated the profile of circRNAs in osteoclasts infected by intracellular S. aureus through high-throughput RNA sequencing. In total, 24 upregulated and 62 downregulated differentially expressed circRNAs were identified and subsequently analyzed to demonstrate their potential functions. On this basis, three circRNAs (chr4:130718154-130728164+, chr8:77409548-77413627-, and chr1:190871592-190899571-) were confirmed as potential novel biomarkers for the diagnosis of osteomyelitis through the murine model of osteomyelitis. Most importantly, we verified that the circRNA chr4:130718154-130728164+ named circPum1 could regulate the host autophagy to affect the intracellular infection of S. aureus through miR-767. In addition, circPum1 could serve as a promising serum biomarker in osteomyelitis patients caused by S. aureus infection. Taken together, this study provided the first global transcriptomic profile analysis of circRNAs in osteoclasts infected by intracellular S. aureus and first proposed a novel perspective for the pathogenesis and immunotherapy of S. aureus-induced osteomyelitis from the term of circRNAs.
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Affiliation(s)
- Zhihao Chen
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Zonggang Xie
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Mingxiao Han
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Qiyuan Jin
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Ziyuan Li
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Yaxuan Zhai
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Minxing Zhang
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Gangfeng Hu
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
| | - Haifang Zhang
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, People’s Republic of China
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Cecotto L, Stapels DAC, van Kessel KPM, Croes M, Lourens Z, Vogely HC, van der Wal BCH, van Strijp JAG, Weinans H, Amin Yavari S. Evaluation of silver bio-functionality in a multicellular in vitro model: towards reduced animal usage in implant-associated infection research. Front Cell Infect Microbiol 2023; 13:1186936. [PMID: 37342248 PMCID: PMC10277478 DOI: 10.3389/fcimb.2023.1186936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 05/16/2023] [Indexed: 06/22/2023] Open
Abstract
Background Despite the extensive use of silver ions or nanoparticles in research related to preventing implant-associated infections (IAI), their use in clinical practice has been debated. This is because the strong antibacterial properties of silver are counterbalanced by adverse effects on host cells. One of the reasons for this may be the lack of comprehensive in vitro models that are capable of analyzing host-bacteria and host-host interactions. Methods and results In this study, we tested silver efficacy through multicellular in vitro models involving macrophages (immune system), mesenchymal stem cells (MSCs, bone cells), and S. aureus (pathogen). Our model showed to be capable of identifying each element of culture as well as tracking the intracellular survival of bacteria. Furthermore, the model enabled to find a therapeutic window for silver ions (AgNO3) and silver nanoparticles (AgNPs) where the viability of host cells was not compromised, and the antibacterial properties of silver were maintained. While AgNO3 between 0.00017 and 0.017 µg/mL retained antibacterial properties, host cell viability was not affected. The multicellular model, however, demonstrated that those concentrations had no effect on the survival of S. aureus, inside or outside host cells. Similarly, treatment with 20 nm AgNPs did not influence the phagocytic and killing capacity of macrophages or prevent S. aureus from invading MSCs. Moreover, exposure to 100 nm AgNPs elicited an inflammatory response by host cells as detected by the increased production of TNF-α and IL-6. This was visible only when macrophages and MSCs were cultured together. Conclusions Multicellular in vitro models such as the one used here that simulate complex in vivo scenarios can be used to screen other therapeutic compounds or antibacterial biomaterials without the need to use animals.
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Affiliation(s)
- Leonardo Cecotto
- Department of Orthopedics, University Medical Center Utrecht, Utrecht, Netherlands
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Daphne A. C. Stapels
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
- Infection Biology Group, Department of Biomolecular Health Sciences, Utrecht University, Utrecht, Netherlands
| | - Kok P. M. van Kessel
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Michiel Croes
- Department of Orthopedics, University Medical Center Utrecht, Utrecht, Netherlands
| | - Zeldali Lourens
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - H. Charles Vogely
- Department of Orthopedics, University Medical Center Utrecht, Utrecht, Netherlands
| | | | - Jos A. G. van Strijp
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Harrie Weinans
- Department of Orthopedics, University Medical Center Utrecht, Utrecht, Netherlands
- Department of Biomechanical Engineering, Delft University of Technology, Delft, Netherlands
| | - Saber Amin Yavari
- Department of Orthopedics, University Medical Center Utrecht, Utrecht, Netherlands
- Regenerative Medicine Centre Utrecht, Utrecht University, Utrecht, Netherlands
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9
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Granata V, Possetti V, Parente R, Bottazzi B, Inforzato A, Sobacchi C. The osteoblast secretome in Staphylococcus aureus osteomyelitis. Front Immunol 2022; 13:1048505. [PMID: 36483565 PMCID: PMC9723341 DOI: 10.3389/fimmu.2022.1048505] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/03/2022] [Indexed: 11/23/2022] Open
Abstract
Osteomyelitis (OM) is an infectious disease of the bone predominantly caused by the opportunistic bacterium Staphylococcus aureus (S. aureus). Typically established upon hematogenous spread of the pathogen to the musculoskeletal system or contamination of the bone after fracture or surgery, osteomyelitis has a complex pathogenesis with a critical involvement of both osteal and immune components. Colonization of the bone by S. aureus is traditionally proposed to induce functional inhibition and/or apoptosis of osteoblasts, alteration of the RANKL/OPG ratio in the bone microenvironment and activation of osteoclasts; all together, these events locally subvert tissue homeostasis causing pathological bone loss. However, this paradigm has been challenged in recent years, in fact osteoblasts are emerging as active players in the induction and orientation of the immune reaction that mounts in the bone during an infection. The interaction with immune cells has been mostly ascribed to osteoblast-derived soluble mediators that add on and synergize with those contributed by professional immune cells. In this respect, several preclinical and clinical observations indicate that osteomyelitis is accompanied by alterations in the local and (sometimes) systemic levels of both pro-inflammatory (e.g., IL-6, IL-1α, TNF-α, IL-1β) and anti-inflammatory (e.g., TGF-β1) cytokines. Here we revisit the role of osteoblasts in bacterial OM, with a focus on their secretome and its crosstalk with cellular and molecular components of the bone microenvironment and immune system.
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Affiliation(s)
- Valentina Granata
- IRCCS Humanitas Research Hospital, Rozzano, Italy,Milan Unit, National Research Council - Institute for Genetic and Biomedical Research (CNR-IRGB), Milan, Italy
| | - Valentina Possetti
- IRCCS Humanitas Research Hospital, Rozzano, Italy,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Italy
| | | | | | - Antonio Inforzato
- IRCCS Humanitas Research Hospital, Rozzano, Italy,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Italy
| | - Cristina Sobacchi
- IRCCS Humanitas Research Hospital, Rozzano, Italy,Milan Unit, National Research Council - Institute for Genetic and Biomedical Research (CNR-IRGB), Milan, Italy,*Correspondence: Cristina Sobacchi,
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Chen Y, Hu H, Huang F, Ling Z, Chen B, Tan B, Wang T, Liu X, Liu C, Zou X. Cocktail of isobavachalcone and curcumin enhance eradication of Staphylococcus aureus biofilm from orthopedic implants by gentamicin and alleviate inflammatory osteolysis. Front Microbiol 2022; 13:958132. [PMID: 36212814 PMCID: PMC9537636 DOI: 10.3389/fmicb.2022.958132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/24/2022] [Indexed: 11/13/2022] Open
Abstract
Orthopedic device-related infection (ODRI) caused by Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA) biofilm may lead to persist infection and severe inflammatory osteolysis. Previous studies have demonstrated that both isobavachalcone and curcumin possess antimicrobial activity, recent studies also reveal their antiosteoporosis, anti-inflammation, and immunoregulatory effect. Thus, this study aims to investigate whether the combination of isobavachalcone and curcumin can enhance the anti-S. aureus biofilm activity of gentamicin and alleviate inflammatory osteolysis in vivo. EUCAST and a standardized MBEC assay were used to verify the synergy between isobavachalcone and curcumin with gentamicin against planktonic S. aureus and its biofilm in vitro, then the antimicrobial and immunoregulatory effect of cocktail therapy was demonstrated in a femoral ODRI mouse model in vivo by μCT analysis, histopathology, quantification of bacteria in bone and myeloid-derived suppressor cell (MDSC) in bone marrow. We tested on standard MSSA ATCC25923 and MRSA USA300, 5 clinical isolated MSSA, and 2 clinical isolated MRSA strains and found that gentamicin with curcumin (62.5–250 μg/ml) and gentamicin with isobavachalcone (1.56 μg/ml) are synergistic against planktonic MSSA, while gentamicin (128 μg/ml) with curcumin (31.25–62.5, 250–500 μg/ml) and gentamicin (64–128 μg/ml) with isobavachalcone (1.56–12.5 μg/ml) exhibit synergistic effect against MSSA biofilm. Results of further study revealed that cocktail of 128 μg/ml gentamicin together with 125 μg/ml curcumin +6.25 μg/ml isobavachalcone showed promising biofilm eradication effect with synergy against USA300 biofilm in vitro. Daily intraperitoneal administration of 20 mg/kg/day isobavachalcone, 20 mg/kg/day curcumin, and 20 mg/kg/day gentamicin, can reduce inflammatory osteolysis and maintain microarchitecture of trabecular bone during orthopedic device-related MRSA infection in mice. Cocktail therapy also enhanced reduction of MDSC M1 polarization in peri-implant tissue, suppression of MDSC amplification in bone marrow, and Eradication of USA300 biofilm in vivo. Together, these results suggest that the combination of isobavachalcone and curcumin as adjuvants administrated together with gentamicin significantly enhances its antimicrobial effect against S. aureus biofilm, and can also modify topical inflammation in ODRI and protect bone microstructure in vivo, which may serve as a potential treatment strategy, especially for S. aureus induced ODRI.
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Affiliation(s)
- Yan Chen
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Hao Hu
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Fangli Huang
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zemin Ling
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Bolin Chen
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Bizhi Tan
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Tingxuan Wang
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiao Liu
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Chun Liu
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Precision Medicine Institute, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- *Correspondence: Chun Liu,
| | - Xuenong Zou
- Department of Spine Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Orthopaedics and Traumatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
- Xuenong Zou,
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11
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Li J, Wen Q, Gu F, An L, Yu T. Non-antibiotic strategies for prevention and treatment of internalized Staphylococcus aureus. Front Microbiol 2022; 13:974984. [PMID: 36118198 PMCID: PMC9471010 DOI: 10.3389/fmicb.2022.974984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/08/2022] [Indexed: 12/01/2022] Open
Abstract
Staphylococcus aureus (S. aureus) infections are often difficult to cure completely. One of the main reasons for this difficulty is that S. aureus can be internalized into cells after infecting tissue. Because conventional antibiotics and immune cells have difficulty entering cells, the bacteria can survive long enough to cause recurrent infections, which poses a serious burden in healthcare settings because repeated infections drastically increase treatment costs. Therefore, preventing and treating S. aureus internalization is becoming a research hotspot. S. aureus internalization can essentially be divided into three phases: (1) S. aureus binds to the extracellular matrix (ECM), (2) fibronectin (Fn) receptors mediate S. aureus internalization into cells, and (3) intracellular S. aureus and persistence into cells. Different phases require different treatments. Many studies have reported on different treatments at different phases of bacterial infection. In the first and second phases, the latest research results show that the cell wall-anchored protein vaccine and some microbial agents can inhibit the adhesion of S. aureus to host cells. In the third phase, nanoparticles, photochemical internalization (PCI), cell-penetrating peptides (CPPs), antimicrobial peptides (AMPs), and bacteriophage therapy can effectively eliminate bacteria from cells. In this paper, the recent progress in the infection process and the prevention and treatment of S. aureus internalization is summarized by reviewing a large number of studies.
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Affiliation(s)
- Jiangbi Li
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Qiangqiang Wen
- Department of Orthopedics, The Affiliated Hospital of Northwest University, Xi’an, China
| | - Feng Gu
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Lijuan An
- Department of Rehabilitation Medicine, The Second Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Tiecheng Yu
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
- *Correspondence: Tiecheng Yu,
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12
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Zelmer AR, Nelson R, Richter K, Atkins GJ. Can intracellular Staphylococcus aureus in osteomyelitis be treated using current antibiotics? A systematic review and narrative synthesis. Bone Res 2022; 10:53. [PMID: 35961964 PMCID: PMC9374758 DOI: 10.1038/s41413-022-00227-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/26/2022] [Accepted: 06/15/2022] [Indexed: 11/09/2022] Open
Abstract
Approximately 40% of treatments of chronic and recurrent osteomyelitis fail in part due to bacterial persistence. Staphylococcus aureus, the predominant pathogen in human osteomyelitis, is known to persist by phenotypic adaptation as small-colony variants (SCVs) and by formation of intracellular reservoirs, including those in major bone cell types, reducing susceptibility to antibiotics. Intracellular infections with S. aureus are difficult to treat; however, there are no evidence-based clinical guidelines addressing these infections in osteomyelitis. We conducted a systematic review of the literature to determine the demonstrated efficacy of all antibiotics against intracellular S. aureus relevant to osteomyelitis, including protein biosynthesis inhibitors (lincosamides, streptogramins, macrolides, oxazolidines, tetracyclines, fusidic acid, and aminoglycosides), enzyme inhibitors (fluoroquinolones and ansamycines), and cell wall inhibitors (beta-lactam inhibitors, glycopeptides, fosfomycin, and lipopeptides). The PubMed and Embase databases were screened for articles related to intracellular S. aureus infections that compared the effectiveness of multiple antibiotics or a single antibiotic together with another treatment, which resulted in 34 full-text articles fitting the inclusion criteria. The combined findings of these studies were largely inconclusive, most likely due to the plethora of methodologies utilized. Therefore, the reported findings in the context of the models employed and possible solutions for improved understanding are explored here. While rifampicin, oritavancin, linezolid, moxifloxacin and oxacillin were identified as the most effective potential intracellular treatments, the scientific evidence for these is still relatively weak. We advocate for more standardized research on determining the intracellular effectiveness of antibiotics in S. aureus osteomyelitis to improve treatments and patient outcomes.
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Affiliation(s)
- Anja R Zelmer
- Centre for Orthopaedic and Trauma Research, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, 5000, Australia
| | - Renjy Nelson
- Department of Infectious Diseases, Central Adelaide Local Health Network, Adelaide, SA, 5000, Australia.,Royal Adelaide Hospital, Adelaide, SA, 5000, Australia
| | - Katharina Richter
- Richter Lab, Department of Surgery, Basil Hetzel Institute for Translational Health Research, University of Adelaide, Adelaide, SA, 5011, Australia
| | - Gerald J Atkins
- Centre for Orthopaedic and Trauma Research, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, 5000, Australia.
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13
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Pathogenesis of pneumonia and acute lung injury. Clin Sci (Lond) 2022; 136:747-769. [PMID: 35621124 DOI: 10.1042/cs20210879] [Citation(s) in RCA: 72] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/29/2022] [Accepted: 05/09/2022] [Indexed: 12/15/2022]
Abstract
Pneumonia and its sequelae, acute lung injury, present unique challenges for pulmonary and critical care healthcare professionals, and these challenges have recently garnered global attention due to the ongoing Sars-CoV-2 pandemic. One limitation to translational investigation of acute lung injury, including its most severe manifestation (acute respiratory distress syndrome, ARDS) has been heterogeneity resulting from the clinical and physiologic diagnosis that represents a wide variety of etiologies. Recent efforts have improved our understanding and approach to heterogeneity by defining sub-phenotypes of ARDS although significant gaps in knowledge remain. Improving our mechanistic understanding of acute lung injury and its most common cause, infectious pneumonia, can advance our approach to precision targeted clinical interventions. Here, we review the pathogenesis of pneumonia and acute lung injury, including how respiratory infections and lung injury disrupt lung homoeostasis, and provide an overview of respiratory microbial pathogenesis, the lung microbiome, and interventions that have been demonstrated to improve outcomes-or not-in human clinical trials.
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14
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Qu X, Wang M, Wang M, Tang H, Zhang S, Yang H, Yuan W, Wang Y, Yang J, Yue B. Multi-Mode Antibacterial Strategies Enabled by Gene-Transfection and Immunomodulatory Nanoparticles in 3D-Printed Scaffolds for Synergistic Exogenous and Endogenous Treatment of Infections. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2200096. [PMID: 35267223 DOI: 10.1002/adma.202200096] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 02/24/2022] [Indexed: 06/14/2023]
Abstract
As research on refractory Staphylococcus aureus-related implant infection intensifies, certain challenges remain, including low antibiotic concentrations within infected areas, immune escape achieved by intracellular bacteria, myeloid-derived suppressor cells (MDSCs) inducing regional immunosuppression, and recurrence of residual pathogenic bacteria after drug suspension. Herein, a novel antimicrobial system to simultaneously address these issues is proposed. Specifically, an oxygen-species-responsive 3D-printed scaffold with shell-core nanoparticles is designed, which are loaded with an antimicrobial peptide plasmid (LL37 plasmid) and have LL37 grafted on their surface (LL37@ZIF8-LL37). The surface-grafted LL37 directly kills S. aureus and, following entry into cells, the nanoparticles kill intracellular bacteria. Moreover, in vitro and in vivo, following translation of the LL37 plasmid, cells function as factories of the antimicrobial peptide, thereby generating a continuous, prolonged antibacterial effect at the site of infection. This system significantly reduces the abnormal increase in MDSCs within the infected microenvironment, thus relieving the immunosuppressive state and restoring a protective antimicrobial immune response. Hence, this proposed antimicrobial system provides an antimicrobial immune response and a novel strategy for S. aureus-related infections by offering a combined active antimicrobial and immunotherapeutic strategy, thereby significantly reducing the recurrence rate following recovery from implant-associated infections.
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Affiliation(s)
- Xinhua Qu
- Department of Bone and Joint Surgery, Department of Orthopedics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle Road, Shanghai, 200001, P. R. China
| | - Minqi Wang
- Department of Bone and Joint Surgery, Department of Orthopedics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle Road, Shanghai, 200001, P. R. China
| | - Miaochen Wang
- Department of Oral and Maxillofacial-Head and Neck Oncology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, 639 Zhizaoju Road, Shanghai, 200011, P. R. China
| | - Haozheng Tang
- Department of Bone and Joint Surgery, Department of Orthopedics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle Road, Shanghai, 200001, P. R. China
| | - Shutao Zhang
- Department of Bone and Joint Surgery, Department of Orthopedics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle Road, Shanghai, 200001, P. R. China
| | - Hongtao Yang
- School of Medical Science and Engineering, Beihang University, Beijing, 100191, P. R. China
| | - Weien Yuan
- Pharm-X Center, Engineering Research Center of Cell and Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China
| | - You Wang
- Department of Bone and Joint Surgery, Department of Orthopedics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle Road, Shanghai, 200001, P. R. China
| | - Jianping Yang
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, P. R. China
| | - Bing Yue
- Department of Bone and Joint Surgery, Department of Orthopedics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 145 Shandong Middle Road, Shanghai, 200001, P. R. China
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15
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Chen Y, Huang C, Chen X, Cai Y, Li W, Fang X, Zhang W. Bone protein analysis via label-free quantitative proteomics in patients with periprosthetic joint infection. J Proteomics 2022; 252:104448. [PMID: 34883267 DOI: 10.1016/j.jprot.2021.104448] [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: 06/27/2021] [Revised: 11/18/2021] [Accepted: 11/23/2021] [Indexed: 11/17/2022]
Abstract
Periprosthetic joint infection (PJI) is a catastrophic complication of arthroplasty. The treatment of PJI often requires multiple operations and long-term use of antibiotics, making PJI a substantial health and economic burden for patients. Therefore, there is an urgent need to elucidate the pathological mechanism of PJI to explore new therapeutic methods. This study aimed to explore proteomics changes in bone tissue around the prosthesis during PJI development, to explain the pathological mechanism and to provide new treatment ideas. Ten patients who underwent revision surgery at our institution were included: 5 patients with Staphylococcus aureus PJI and 5 patients with aseptic failure. The proteomics changes in bone tissues after PJI were investigated by label-free quantitative proteomics, and the pathways affected by the differential proteins were analyzed by GO annotation, GO enrichment analysis, KEGG enrichment analysis and protein-protein interaction network analysis. We identified 435 differentially expressed proteins (DEPs), with 213 upregulated and 222 downregulated proteins. Analysis revealed activation of immune-related pathways, such as complement and coagulation cascades, phagocytosis, and neutrophil activation, and inhibition of energy metabolism pathways represented by the TCA cycle. We also observed an altered balance between osteoblasts and osteoclasts during S. aureus PJI. We hope that these processes will reveal new treatment ideas. SIGNIFICANCE: PJI is a catastrophic complication of arthroplasty. When infection occurs, bacteria may invade periprosthetic bone tissue to escape immunity and cause damage. So far, only few studies focused on the changes of proteomics associated to PJI. This is the first study to describe the proteomics changes of periprosthetic bone tissue of patients with PJI. We found that the pathological process of S. aureus PJI mainly involves activation of the immune system, decreased energy metabolism, and an altered balance of osteoblasts and osteoclasts.
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Affiliation(s)
- Yang Chen
- Department of Orthopedic Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Changyu Huang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Xiaoqing Chen
- Department of Orthopedic Surgery, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou, China
| | - Yuanqing Cai
- Department of Orthopedic Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Wenbo Li
- Department of Orthopedic Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Xinyu Fang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
| | - Wenming Zhang
- Department of Orthopedic Surgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
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16
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Desgranges E, Barrientos L, Herrgott L, Marzi S, Toledo-Arana A, Moreau K, Vandenesch F, Romby P, Caldelari I. The 3'UTR-derived sRNA RsaG coordinates redox homeostasis and metabolism adaptation in response to glucose-6-phosphate uptake in Staphylococcus aureus. Mol Microbiol 2021; 117:193-214. [PMID: 34783400 DOI: 10.1111/mmi.14845] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 11/08/2021] [Accepted: 11/11/2021] [Indexed: 01/28/2023]
Abstract
Staphylococcus aureus RsaG is a 3'-untranslated region (3'UTR) derived sRNA from the conserved uhpT gene encoding a glucose-6-phosphate (G6P) transporter expressed in response to extracellular G6P. The transcript uhpT-RsaG undergoes degradation from 5'- to 3'-end by the action of the exoribonucleases J1/J2, which are blocked by a stable hairpin structure at the 5'-end of RsaG, leading to its accumulation. RsaG together with uhpT is induced when bacteria are internalized into host cells or in the presence of mucus-secreting cells. Using MS2-affinity purification coupled with RNA sequencing, several RNAs were identified as targets including mRNAs encoding the transcriptional factors Rex, CcpA, SarA, and the sRNA RsaI. Our data suggested that RsaG contributes to the control of redox homeostasis and adjusts metabolism to changing environmental conditions. RsaG uses different molecular mechanisms to stabilize, degrade, or repress the translation of its mRNA targets. Although RsaG is conserved only in closely related species, the uhpT 3'UTR of the ape pathogen S. simiae harbors an sRNA, whose sequence is highly different, and which does not respond to G6P levels. Our results hypothesized that the 3'UTRs from UhpT transporter encoding mRNAs could have rapidly evolved to enable adaptation to host niches.
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Affiliation(s)
- Emma Desgranges
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Laura Barrientos
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Lucas Herrgott
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Stefano Marzi
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | | | - Karen Moreau
- CIRI, Centre International de Recherche en Infectiologie, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Hospices Civils de Lyon, Université de Lyon, Lyon, France
| | - François Vandenesch
- CIRI, Centre International de Recherche en Infectiologie, Inserm, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, École Normale Supérieure de Lyon, Hospices Civils de Lyon, Université de Lyon, Lyon, France
| | - Pascale Romby
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
| | - Isabelle Caldelari
- Architecture et Réactivité de l'ARN, UPR9002, CNRS, Université de Strasbourg, Strasbourg, France
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17
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Intracellular S. aureus in Osteoblasts in a Clinical Sample from a Patient with Chronic Osteomyelitis-A Case Report. Pathogens 2021; 10:pathogens10081064. [PMID: 34451528 PMCID: PMC8401219 DOI: 10.3390/pathogens10081064] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/17/2021] [Accepted: 08/20/2021] [Indexed: 11/16/2022] Open
Abstract
The pathophysiological role of intracellular bacteria in osteomyelitis is still a matter of debate. Here, we demonstrate for the first time the presence of Staphylococcus aureus internalized into osteoblasts in human tissue samples of a case with a chronic osteomyelitis using ultrastructural transmission electron microscope analysis.
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18
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Toledano-Osorio M, Manzano-Moreno FJ, Toledano M, Medina-Castillo AL, Costela-Ruiz VJ, Ruiz C, Osorio R. Doxycycline-Doped Polymeric Membranes Induced Growth, Differentiation and Expression of Antigenic Phenotype Markers of Osteoblasts. Polymers (Basel) 2021; 13:1063. [PMID: 33800569 PMCID: PMC8037272 DOI: 10.3390/polym13071063] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/23/2021] [Accepted: 03/25/2021] [Indexed: 12/11/2022] Open
Abstract
Polymeric membranes are employed in guided bone regeneration (GBR) as physical barriers to facilitate bone in-growth. A bioactive and biomimetic membrane with the ability to participate in the healing and regeneration of the bone is necessary. The aim of the present study was to analyze how novel silicon dioxide composite membranes functionalized with zinc or doxycycline can modulate the osteoblasts' proliferation, differentiation, and expression of selected antigenic markers related to immunomodulation. Nanostructured acrylate-based membranes were developed, blended with silica, and functionalized with zinc or doxycycline. They were subjected to MG63 osteoblast-like cells culturing. Proliferation was assessed by MTT-assay, differentiation by evaluating the alkaline phosphatase activity by a spectrophotometric method and antigenic phenotype was assessed by flow cytometry for selected markers. Mean comparisons were conducted by one-way ANOVA and Tukey tests (p < 0.05). The blending of silica nanoparticles in the tested non-resorbable polymeric scaffold improved the proliferation and differentiation of osteoblasts, but doxycycline doped scaffolds attained the best results. Osteoblasts cultured on doxycycline functionalized membranes presented higher expression of CD54, CD80, CD86, and HLA-DR, indicating a beneficial immunomodulation activity. Doxycycline doped membranes may be a potential candidate for use in GBR procedures in several challenging pathologies, including periodontal disease.
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Affiliation(s)
- Manuel Toledano-Osorio
- Colegio Máximo de Cartuja s/n, Faculty of Dentistry, University of Granada, 18071 Granada, Spain; (M.T.-O.); (R.O.)
- Medicina Clínica y Salud Pública Programme, University of Granada, 18071 Granada, Spain
| | - Francisco J. Manzano-Moreno
- Biomedical Group (BIO277), Department of Stomatology, School of Dentistry, University of Granada, 18071 Granada, Spain;
- Instituto Investigación Biosanitaria, ibs.Granada, 18071 Granada, Spain; (V.J.C.-R.); (C.R.)
| | - Manuel Toledano
- Colegio Máximo de Cartuja s/n, Faculty of Dentistry, University of Granada, 18071 Granada, Spain; (M.T.-O.); (R.O.)
| | - Antonio L. Medina-Castillo
- NanoMyP, Nanomateriales y Polimeros S.L., Spin-Off Company of the University of Granada, Edificio BIC-Granada, Av. Innovación 1, Armilla, 18016 Granada, Spain;
| | - Victor J. Costela-Ruiz
- Instituto Investigación Biosanitaria, ibs.Granada, 18071 Granada, Spain; (V.J.C.-R.); (C.R.)
- Biomedical Group (BIO277), Department of Nursing, Faculty of Health Sciences, University of Granada, 18071 Granada, Spain
| | - Concepción Ruiz
- Instituto Investigación Biosanitaria, ibs.Granada, 18071 Granada, Spain; (V.J.C.-R.); (C.R.)
- Biomedical Group (BIO277), Department of Nursing, Faculty of Health Sciences, University of Granada, 18071 Granada, Spain
- Institute of Neuroscience, University of Granada, Centro de Investigación Biomédica (CIBM), Parque de Tecnológico de la Salud (PTS), 18071 Granada, Spain
| | - Raquel Osorio
- Colegio Máximo de Cartuja s/n, Faculty of Dentistry, University of Granada, 18071 Granada, Spain; (M.T.-O.); (R.O.)
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19
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Staphylococcus aureus Internalization in Osteoblast Cells: Mechanisms, Interactions and Biochemical Processes. What Did We Learn from Experimental Models? Pathogens 2021; 10:pathogens10020239. [PMID: 33669789 PMCID: PMC7922271 DOI: 10.3390/pathogens10020239] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/12/2021] [Accepted: 02/17/2021] [Indexed: 02/07/2023] Open
Abstract
Bacterial internalization is a strategy that non-intracellular microorganisms use to escape the host immune system and survive inside the human body. Among bacterial species, Staphylococcus aureus showed the ability to interact with and infect osteoblasts, causing osteomyelitis as well as bone and joint infection, while also becoming increasingly resistant to antibiotic therapy and a reservoir of bacteria that can make the infection difficult to cure. Despite being a serious issue in orthopedic surgery, little is known about the mechanisms that allow bacteria to enter and survive inside the osteoblasts, due to the lack of consistent experimental models. In this review, we describe the current knowledge about S. aureus internalization mechanisms and various aspects of the interaction between bacteria and osteoblasts (e.g., best experimental conditions, bacteria-induced damages and immune system response), focusing on studies performed using the MG-63 osteoblastic cell line, the best traditional (2D) model for the study of this phenomenon to date. At the same time, as it has been widely demonstrated that 2D culture systems are not completely indicative of the dynamic environment in vivo, and more recent 3D models—representative of bone infection—have also been investigated.
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20
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Zoller SD, Hegde V, Burke ZDC, Park HY, Ishmael CR, Blumstein GW, Sheppard W, Hamad C, Loftin AH, Johansen DO, Smith RA, Sprague MM, Hori KR, Clarkson SJ, Borthwell R, Simon SI, Miller JF, Nelson SD, Bernthal NM. Evading the host response: Staphylococcus "hiding" in cortical bone canalicular system causes increased bacterial burden. Bone Res 2020; 8:43. [PMID: 33303744 PMCID: PMC7728749 DOI: 10.1038/s41413-020-00118-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 08/22/2020] [Accepted: 09/17/2020] [Indexed: 02/07/2023] Open
Abstract
Extremity reconstruction surgery is increasingly performed rather than amputation for patients with large-segment pathologic bone loss. Debate persists as to the optimal void filler for this "limb salvage" surgery, whether metal or allograft bone. Clinicians focus on optimizing important functional gains for patients, and the risk of devastating implant infection has been thought to be similar regardless of implant material. Recent insights into infection pathophysiology are challenging this equipoise, however, with both basic science data suggesting a novel mechanism of infection of Staphylococcus aureus (the most common infecting agent) into the host lacunar-canaliculi network, and also clinical data revealing a higher rate of infection of allograft over metal. The current translational study was therefore developed to bridge the gap between these insights in a longitudinal murine model of infection of allograft bone and metal. Real-time Staphylococci infection characteristics were quantified in cortical bone vs metal, and both microarchitecture of host implant and presence of host immune response were assessed. An orders-of-magnitude higher bacterial burden was established in cortical allograft bone over both metal and cancellous bone. The establishment of immune-evading microabscesses was confirmed in both cortical allograft haversian canal and the submicron canaliculi network in an additional model of mouse femur bone infection. These study results reveal a mechanism by which Staphylococci evasion of host immunity is possible, contributing to elevated risks of infection in cortical bone. The presence of this local infection reservoir imparts massive clinical implications that may alter the current paradigm of osteomyelitis and bulk allograft infection treatment.
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Affiliation(s)
- Stephen D Zoller
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Vishal Hegde
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Zachary D C Burke
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Howard Y Park
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Chad R Ishmael
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Gideon W Blumstein
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - William Sheppard
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Christopher Hamad
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Amanda H Loftin
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Daniel O Johansen
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
| | - Ryan A Smith
- David Geffen School of Medicine, University of California, Los Angeles, 10833 Le Conte Ave, Los Angeles, CA, 90095, USA
| | - Marina M Sprague
- Department of Internal Medicine, University of California, Los Angeles, 757 Westwood Plaza, Suite 7501, Los Angeles, CA, 90095, USA
| | - Kellyn R Hori
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA
- David Geffen School of Medicine, University of California, Los Angeles, 10833 Le Conte Ave, Los Angeles, CA, 90095, USA
| | - Samuel J Clarkson
- David Geffen School of Medicine, University of California, Los Angeles, 10833 Le Conte Ave, Los Angeles, CA, 90095, USA
| | - Rachel Borthwell
- David Geffen School of Medicine, University of California, Los Angeles, 10833 Le Conte Ave, Los Angeles, CA, 90095, USA
| | - Scott I Simon
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, 95616, USA
| | - Jeff F Miller
- California NanoSystems Institute, University of California, Los Angeles, 570 Westwood Plaza, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine, University of California, Los Angeles, 90095, USA
| | - Scott D Nelson
- Department of Pathology, University of California, Los Angeles, 1250 16th St Suite 3450, Santa Monica, CA, 90404, USA
| | - Nicholas M Bernthal
- Department of Orthopedic Surgery, University of California, Los Angeles, 1250 16th St Suite 2100, Santa Monica, CA, 90404, USA.
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21
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Hsieh E, Shiau S, Nolan O, Gibert CL, Bedimo RJ, Rodriguez-Barradas MC, Justice AC, Womack JA, Yin MT. Increased Fragility Fracture Rates in Older Men With Osteomyelitis. Clin Infect Dis 2020; 69:1239-1242. [PMID: 30715288 DOI: 10.1093/cid/ciz077] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 01/23/2019] [Indexed: 12/15/2022] Open
Abstract
In this study, we evaluated fracture incidence over a 10-year period among men with and without osteomyelitis from the Veterans Aging Cohort Study. Fracture incidence was significantly higher among those with osteomyelitis at all osteoporotic fracture sites after adjusting for key related risk factors. Future prospective studies are warranted.
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Affiliation(s)
- Evelyn Hsieh
- Section of Rheumatology, Allergy and Clinical Immunology, Yale School of Medicine, New Haven.,Veteran Affairs (VA) Connecticut Healthcare System, West Haven
| | | | - Olivia Nolan
- Division of Infectious Diseases, Columbia University Medical Center, New York, New York
| | - Cynthia L Gibert
- Medical Service, Section of Infectious Diseases, Washington DC VA Medical Center, Washington, DC.,Division of Infectious Diseases, George Washington University School of Medicine, Washington, DC
| | - Roger J Bedimo
- Section of Infectious Diseases, VA North Texas Healthcare System, Dallas, Texas
| | - Maria C Rodriguez-Barradas
- Infectious Diseases Section, Michael E DeBakey VA Medical Center, Houston.,Department of Medicine, Baylor College of Medicine Houston, Texas
| | - Amy C Justice
- Veteran Affairs (VA) Connecticut Healthcare System, West Haven.,Section of General Internal Medicine, Yale School of Medicine, New Haven
| | - Julie A Womack
- Veteran Affairs (VA) Connecticut Healthcare System, West Haven.,Yale School of Nursing, West Haven, Connecticut
| | - Michael T Yin
- Division of Infectious Diseases, Columbia University Medical Center, New York, New York
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22
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Fu F, Zhang Y, Li L, Wang H, Li Q, Tao X, Song Y, Song E. Intracellular Pathogen Detection Based on Dual-Recognition Units Constructed Fluorescence Resonance Energy Transfer Nanoprobe. Anal Chem 2020; 92:11462-11468. [PMID: 32693581 DOI: 10.1021/acs.analchem.0c02695] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The intracellular invasion and survival of a pathogen like Staphylococcus aureus (S. aureus) within host cells enable them to resist antibiotic treatment and colonize long-term in the host, which leads to a series of clinical issues. Rapid and specific detection of intracellular bacteria is important in diagnosis of infection and guiding antibiotic administration. Herein, this work reports a simple one-step fluorescence resonance energy transfer (FRET) platform-based strategy to achieve specific and rapid detection of S. aureus in specimens of phagocytic cells. The aptamer modified quantum dots (Aptamer-QDs) and antibiotic molecule of Teicoplanin functionalized-gold nanoparticles (Teico-AuNPs) dual-recognition units to S. aureus are employed as energy donor and acceptor, respectively. Based on the "off" to "on" signal readout mode, when in the presence of target S. aureus, the donor and acceptor are close to each other and bring high FRET efficiency, which is suitable for analysis of intracellular S. aureus. After it was incubated with the sample for 2 h, the as-prepared FRET sensor showed selectivity to the target S. aureus, and the changed fluorescence signal shows an obvious variation with increasing concentration of S. aureus in pure buffer. When the FRET strategy was further applied to assay intracellular S. aureus, there was an obvious fluorescence signal change obtained both by spectrum analysis and visual fluorescence microscope observation when the average number of S. aureus in one host cell (NS. aureus/cell) was as low as 1, which can be attributed to the high fluorescence quenching efficiency of about 41.3%. It could be envisioned that this FRET nanoprobe with high fluorescence quenching efficiency may provide a simple approach for the facile, selective, and rapid diagnosis of an intracellular bacterial infection.
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Affiliation(s)
- Fei Fu
- Key laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People's Republic of China
| | - Yaqing Zhang
- College of Food Science, Southwest University, Chongqing 400715, People's Republic of China
| | - Linyao Li
- Key laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People's Republic of China
| | - Hong Wang
- Key laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People's Republic of China
| | - Qingjin Li
- Key laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People's Republic of China
| | - Xiaoqi Tao
- College of Food Science, Southwest University, Chongqing 400715, People's Republic of China
| | - Yang Song
- Key laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People's Republic of China
| | - Erqun Song
- Key laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People's Republic of China
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23
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Kang J, Dietz MJ, Hughes K, Xing M, Li B. Silver nanoparticles present high intracellular and extracellular killing against Staphylococcus aureus. J Antimicrob Chemother 2020; 74:1578-1585. [PMID: 30778552 DOI: 10.1093/jac/dkz053] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 11/20/2018] [Accepted: 01/15/2019] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVES Bone and joint infections caused by Staphylococcus aureus are becoming increasingly difficult to treat due to rising antibiotic resistance, resilient biofilms and intracellular survival of S. aureus. It has been challenging to identify and develop antimicrobial agents that can be used to kill extracellular and intracellular bacteria while having limited toxicity towards host cells. In addressing this challenge, this study investigates the antimicrobial efficacy and toxicity of silver nanoparticles (AgNPs). METHODS Intracellular bacteria were generated using a co-culture model of human osteoblast cells and S. aureus. Extracellular and intracellular S. aureus were treated with AgNPs, antibiotics and their combinations, and numbers of colonies were quantified. Toxicity of AgNPs against human osteoblast cells was determined by quantifying the number of viable cells after treatment. RESULTS AgNPs demonstrated excellent antimicrobial activity against extracellular S. aureus with a 100% killing efficacy at concentrations as low as 56 μM, along with a high intracellular killing efficacy of 76% at 371 μM. AgNPs were non-toxic or slightly toxic towards human osteoblasts at the concentrations studied (up to 927 μM). Moreover, smaller-sized (40 nm) AgNPs were more efficacious in killing bacteria compared with their larger-sized (100 nm) counterparts and synergistic antimicrobial effects against extracellular bacteria were observed when AgNPs were combined with gentamicin. CONCLUSIONS AgNPs and their combination with antibiotics have demonstrated high extracellular and intracellular bacterial killing and presented unique aspects for potential clinical applications, especially for chronic and recurrent infections where intracellular bacteria may be the cause.
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Affiliation(s)
- Jason Kang
- Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV, USA
| | - Matthew J Dietz
- Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV, USA
| | - Krystal Hughes
- Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV, USA
| | - Malcolm Xing
- Department of Mechanical Engineering, University of Manitoba, Winnipeg, Canada
- The Children's Hospital Research Institute of Manitoba, Winnipeg, Canada
| | - Bingyun Li
- Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV, USA
- Mary Babb Randolph Cancer Center, Morgantown, WV, USA
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24
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Bongiorno D, Musso N, Lazzaro LM, Mongelli G, Stefani S, Campanile F. Detection of methicillin-resistant Staphylococcus aureus persistence in osteoblasts using imaging flow cytometry. Microbiologyopen 2020; 9:e1017. [PMID: 32237200 PMCID: PMC7221431 DOI: 10.1002/mbo3.1017] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 02/01/2020] [Accepted: 02/10/2020] [Indexed: 11/10/2022] Open
Abstract
Methicillin-resistant S. aureus has been reported as the main pathogen involved in chronic infections, osteomyelitis, and prosthetic joint infections. The host/pathogen interaction is dynamic and requires several changes to promote bacterial survival. Here, we focused on the internalization and persistence behavior of well-characterized Staphylococcus aureus invasive strains belonging to the main ST-MRSA-SCCmec clones. To overcome the limitations of the cell culture method, we comparatively analyzed the ability of internalization within human MG-63 osteoblasts with imaging flow cytometry (IFC). After evaluation by cell culture assay, the MRSA clones in the study were all able to readily internalize at 3h postinfection, the persistence of intracellular bacteria was evaluated at 24h both by routine cell culture and IFC assay, after vancomycin-BODIPY staining. A statistical difference of persistence was found in ST5-SCCmecII (26.59%), ST228-SCCmecI (20.25%), ST8-SCCmecIV (19.52%), ST239-SCCmecIII (47.82%), and ST22-SCCmecIVh (50.55%) showing the same ability to internalize as ATCC12598 (51%), the invasive isolate used as control strain for invasion and persistence assays. We demonstrated that the intracellular persistence process depends on the total number of infected cells. Comparing our data obtained by IFC with those of the cell culture assay, we obtained greater reproducibility rates and a number of intracellular bacteria, with the advantage of analyzing live host cells. Moreover, with some limitations related to the lack of whole-genome sequencing analysis, we validated the different proclivities to persist in the main Italian HA-MRSA invasive isolates and our results highlighted the heterogeneity of the different clones to persist during cell infection.
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Affiliation(s)
- Dafne Bongiorno
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Medical Molecular Microbiology and Antibiotic Resistance Laboratory (MMARLab), University of Catania, Catania, Italy
| | - Nicolò Musso
- Bio-nanotech Research and Innovation Tower (BRIT), University of Catania, Catania, Italy
| | - Lorenzo Mattia Lazzaro
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Medical Molecular Microbiology and Antibiotic Resistance Laboratory (MMARLab), University of Catania, Catania, Italy
| | - Gino Mongelli
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Medical Molecular Microbiology and Antibiotic Resistance Laboratory (MMARLab), University of Catania, Catania, Italy
| | - Stefania Stefani
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Medical Molecular Microbiology and Antibiotic Resistance Laboratory (MMARLab), University of Catania, Catania, Italy.,Bio-nanotech Research and Innovation Tower (BRIT), University of Catania, Catania, Italy
| | - Floriana Campanile
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Medical Molecular Microbiology and Antibiotic Resistance Laboratory (MMARLab), University of Catania, Catania, Italy
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25
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Deramaudt TB, Ali M, Vinit S, Bonay M. Sulforaphane reduces intracellular survival of Staphylococcus aureus in macrophages through inhibition of JNK and p38 MAPK‑induced inflammation. Int J Mol Med 2020; 45:1927-1941. [PMID: 32323751 PMCID: PMC7169961 DOI: 10.3892/ijmm.2020.4563] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 02/11/2020] [Indexed: 12/12/2022] Open
Abstract
Macrophages are active contributors to the innate immune defense system. As macrophage activation is clearly affected by the surrounding microenvironment, the present study investigated the effect of sulforaphane (SFN) on the bactericidal activity of macrophages and the underlying molecular mechanisms involved in this process. Human THP-1-derived macrophages, primary human peripheral blood mononuclear cell-derived macrophages, and primary mouse bone marrow derived-macrophages (BMDMs) pretreated with SFN or DMSO were utilized in a model of Staphylococcus aureus infection. The results suggested that SFN pretreatment of macrophages effectively repressed the intracellular survival of S. aureus through modulation of p38/JNK signaling and decreased S. aureus-induced caspases-3/7-dependent cell apoptosis, potentially through downregulation of microRNA (miR)-142-5p and miR-146a-5p. As SFN is a well-known activator of nuclear factor erythroid 2-related factor 2 (Nrf2), Nrf2−/− BMDMs were used to demonstrate that the SFN-mediated inhibitory effect was independent of Nrf2. Nevertheless, an increase in intracellular bacterial survival in Nrf2-deficient macrophages was observed. In addition, SFN pretreatment suppressed S. aureus-induced transcriptional expression of genes coding for the proinflammatory cytokines interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α), as well as for the M1 markers C-C motif chemokine receptor 7, IL-23 and inducible nitric oxide synthase (iNOS). Western blot analysis indicated that S. aureus challenge activated p38 mitogen-activated protein kinase (MAPK) (p38) and c-Jun N-terminal kinase (JNK) MAPK signaling pathways, while SFN pretreatment prevented p38 and JNK phosphorylation. Pretreatment with 2 specific inhibitors of p38 and JNK, SB203580 and SP600125, respectively, resulted in a decrease in S. aureus-induced proinflammatory gene expression levels compared with those observed in the SFN-pretreated macrophages. Furthermore, THP-1-derived macrophages pretreated with SB203580 or SP600125 prior to bacterial infection exhibited a significant inhibition in intracellular S. aureus survival. In conclusion, we hypothesize that concomitant targeting of the p38/JNK-inflammatory response and the S. aureus-induced apoptosis with SFN may be a promising therapeutic approach in S. aureus infection.
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Affiliation(s)
- Therese B Deramaudt
- Department of Neuromuscular Handicap: Biotherapies and Therapeutic Innovations, National Institute of Health and Medical Research, University of Versailles‑Saint‑Quentin‑en‑Yvelines, 78180 Montigny‑le‑Bretonneux, France
| | - Malika Ali
- Department of Neuromuscular Handicap: Biotherapies and Therapeutic Innovations, National Institute of Health and Medical Research, University of Versailles‑Saint‑Quentin‑en‑Yvelines, 78180 Montigny‑le‑Bretonneux, France
| | - Stephane Vinit
- Department of Neuromuscular Handicap: Biotherapies and Therapeutic Innovations, National Institute of Health and Medical Research, University of Versailles‑Saint‑Quentin‑en‑Yvelines, 78180 Montigny‑le‑Bretonneux, France
| | - Marcel Bonay
- Department of Neuromuscular Handicap: Biotherapies and Therapeutic Innovations, National Institute of Health and Medical Research, University of Versailles‑Saint‑Quentin‑en‑Yvelines, 78180 Montigny‑le‑Bretonneux, France
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26
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Sultana S, Bishayi B. Etoposide-mediated depletion of peripheral blood monocytes post s.aureus infection attenuates septic arthritis by modulating macrophage-derived factors responsible for inflammatory destruction. Immunol Lett 2020; 220:51-62. [PMID: 32032616 DOI: 10.1016/j.imlet.2020.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 01/27/2020] [Accepted: 02/01/2020] [Indexed: 01/16/2023]
Abstract
S.aureus induced septic arthritis remains a serious medical concern due to its rapidly progressive disease profile. The multidrug resistant nature of S.aureus demands the development of new strategies for the treatment of S.aureus arthritis. Since monocyte/macrophage population has been recognized as an important axis in joint inflammation and destruction, selective depletion of peripheral blood monocytes might influence the outcome and progression of the disease. Therefore, in this study we have put forward the concept of monocyte depletion by using etoposide, a drug that selectively depletes the monocyte/macrophage population. Mice were inoculated with live S.aureus for the development of septic arthritis. Post S.aureus infection, etoposide was subcutaneously injected. The severity of arthritis was found to be significantly low in the etoposide treated mice throughout the course. Arthritis index, histopathological analysis and TRAP staining images confirmed effectiveness of etoposide treatment in regulating inflammation and bone cartilage destruction. Lower levels of inflammatory cytokines, ROS, MMP-2, RANKL, OPN and plasmin reflected less severe arthritic destruction after etoposide treatment in arthritic mice. The bacterial load was not increased after etoposide treatment. Together, the presented data suggested that monocyte depletion by etoposide might represent an alternative therapeutic strategy for the treatment of S.aureus arthritis.
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Affiliation(s)
- Sahin Sultana
- Department of Physiology, Immunology and Microbiology laboratory, University of Calcutta, University Colleges of Science and Technology, 92 APC Road, Calcutta, 700009, West Bengal, India
| | - Biswadev Bishayi
- Department of Physiology, Immunology and Microbiology laboratory, University of Calcutta, University Colleges of Science and Technology, 92 APC Road, Calcutta, 700009, West Bengal, India.
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27
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Sari LM, Hakim RF, Mubarak Z, Andriyanto A. Analysis of phenolic compounds and immunomodulatory activity of areca nut extract from Aceh, Indonesia, against Staphylococcus aureus infection in Sprague-Dawley rats. Vet World 2020; 13:134-140. [PMID: 32158163 PMCID: PMC7020107 DOI: 10.14202/vetworld.2020.134-140] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 12/11/2019] [Indexed: 11/23/2022] Open
Abstract
Aim: The aim of the study was to investigate the immunomodulatory activity of areca nut extract. The phytochemical content and phenolic composition of the extract were also determined. Materials and Methods: An extract of areca nut was prepared using 96% ethanol and subsequently screened for phytochemical content using a high-performance liquid chromatography (HPLC) method. The immunomodulatory activity of the extract was tested in 35 Sprague-Dawley rats, divided into four groups: One control group and three experimental groups in which the rats received 500, 1000, or 1500 mg/kg of oral areca nut extract biweekly (BW). The extract was orally administered 14 days before the intraperitoneal challenge with Staphylococcus aureus (1×108 CFU/mL). On the 14th day of the experiment, rats in all the four groups were sacrificed. Measurement of the levels of red blood cells, hematocrit (Hct), hemoglobin (Hb), white blood cells (WBCs), lymphocytes, monocytes, neutrophils, basophils, eosinophil, and macrophages were recorded. The activities of serum glutamate oxalate transaminase, serum glutamate pyruvate transaminase, urea, and creatinine were also determined. Results: Areca nut was found to contain an alkaloid, tannin, and flavonoid compounds. HPLC analysis revealed the presence of catechin as the major compound along with quercetin. Administration of areca nut extract in rats infected with S. aureus produced a significant increase in the concentration of WBC but did not affect Hct, Hb, and other cell types. Among the different doses tested, 1000 mg/kg BW was found to be most effective in cellular immunity models. No harmful effects on the liver and kidney functions were observed. Conclusion: The antioxidant activity of areca nut might be attributed to the presence of catechin and quercetin. Administration of areca nut extract increased the number of WBCs and improved the activity and capacity of macrophages significantly in rats infected with S. aureus.
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Affiliation(s)
- Liza Meutia Sari
- Department of Oral Medicine, Faculty of Dentistry, University of Syiah Kuala, Banda Aceh, Indonesia
| | - Rachmi Fanani Hakim
- Department of Oral Biology, Faculty of Dentistry, University of Syiah Kuala, Banda Aceh, Indonesia
| | - Zaki Mubarak
- Department of Oral Biology, Faculty of Dentistry, University of Syiah Kuala, Banda Aceh, Indonesia
| | - Andriyanto Andriyanto
- Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Bogor Agricultural University, Bogor, Indonesia
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28
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Wen Q, Gu F, Sui Z, Su Z, Yu T. The Process of Osteoblastic Infection by Staphylococcus Aureus. Int J Med Sci 2020; 17:1327-1332. [PMID: 32624688 PMCID: PMC7330672 DOI: 10.7150/ijms.45960] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/18/2020] [Indexed: 12/22/2022] Open
Abstract
Bone infection is difficult to cure, and relapse frequently occurs, which is a major treatment problem. One of the main reasons for the refractory and recurrent nature of bone infection is that bacteria, such as Staphylococcus aureus (S. aureus), can be internalized into osteoblasts after infecting bone tissue, thereby avoiding attack by the immune system and antibiotics. Understanding how bacteria (such as S. aureus) are internalized into osteoblasts is key to effective treatment. S. aureus is the most common pathogenic bacterium that causes bone infection. This paper reviews the literature, analyzes the specific process of osteoblastic S. aureus infection, and summarizes specific treatment strategies to improve bone infection treatment.
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Affiliation(s)
- Qiangqiang Wen
- Department of Orthopedics, First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Feng Gu
- Department of Orthopedics, First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Zhenjiang Sui
- Department of Orthopedics, First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Zilong Su
- Department of Orthopedics, First Hospital of Jilin University, Changchun 130021, Jilin, China
| | - Tiecheng Yu
- Department of Orthopedics, First Hospital of Jilin University, Changchun 130021, Jilin, China
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29
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Dutta D, Mukherjee D, Mukherjee IA, Maiti TK, Basak A, Das AK. Staphylococcal superantigen-like proteins interact with human MAP kinase signaling protein ERK2. FEBS Lett 2019; 594:266-277. [PMID: 31468523 DOI: 10.1002/1873-3468.13590] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/27/2019] [Accepted: 07/29/2019] [Indexed: 01/05/2023]
Abstract
This study aimed to identify the intracellular binding partner of a unique class of staphylococcal secreted exotoxins called superantigen-like proteins (SSL) from human macrophage and keratinocyte cell lysates. Here, we report that SSL1 specifically binds to human extracellular signal-regulated kinase 2 (hERK2), an important stress-activated kinase in mitogen-activated protein kinase signaling pathways. Western blot and in vitro binding studies with recombinant hERK2 confirmed the binding interaction of SSL1, SSL7, and SSL10 with hERK2. Moreover, the SSLs-hERK2 interaction was validated biochemically by ELISA. Our finding shows that SSLs play a novel role by binding with host cell MAP kinase signaling pathway protein. Understanding the SSL-hERK2 interaction will also provide a basis for designing SSL-based peptide inhibitors of hERK2 in cancer therapy.
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Affiliation(s)
- Debabrata Dutta
- Department of Biotechnology, Indian Institute of Technology Kharagpur, India.,Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, India
| | - Devdeep Mukherjee
- Department of Biotechnology, Indian Institute of Technology Kharagpur, India
| | | | - Tapas Kumar Maiti
- Department of Biotechnology, Indian Institute of Technology Kharagpur, India
| | - Amit Basak
- Department of Chemistry, Indian Institute of Technology Kharagpur, India.,School of Bioscience, Indian Institute of Technology Kharagpur, India
| | - Amit Kumar Das
- Department of Biotechnology, Indian Institute of Technology Kharagpur, India.,School of Bioscience, Indian Institute of Technology Kharagpur, India
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30
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Masters EA, Trombetta RP, de Mesy Bentley KL, Boyce BF, Gill AL, Gill SR, Nishitani K, Ishikawa M, Morita Y, Ito H, Bello-Irizarry SN, Ninomiya M, Brodell JD, Lee CC, Hao SP, Oh I, Xie C, Awad HA, Daiss JL, Owen JR, Kates SL, Schwarz EM, Muthukrishnan G. Evolving concepts in bone infection: redefining "biofilm", "acute vs. chronic osteomyelitis", "the immune proteome" and "local antibiotic therapy". Bone Res 2019; 7:20. [PMID: 31646012 PMCID: PMC6804538 DOI: 10.1038/s41413-019-0061-z] [Citation(s) in RCA: 256] [Impact Index Per Article: 51.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 06/17/2019] [Accepted: 06/21/2019] [Indexed: 02/08/2023] Open
Abstract
Osteomyelitis is a devastating disease caused by microbial infection of bone. While the frequency of infection following elective orthopedic surgery is low, rates of reinfection are disturbingly high. Staphylococcus aureus is responsible for the majority of chronic osteomyelitis cases and is often considered to be incurable due to bacterial persistence deep within bone. Unfortunately, there is no consensus on clinical classifications of osteomyelitis and the ensuing treatment algorithm. Given the high patient morbidity, mortality, and economic burden caused by osteomyelitis, it is important to elucidate mechanisms of bone infection to inform novel strategies for prevention and curative treatment. Recent discoveries in this field have identified three distinct reservoirs of bacterial biofilm including: Staphylococcal abscess communities in the local soft tissue and bone marrow, glycocalyx formation on implant hardware and necrotic tissue, and colonization of the osteocyte-lacuno canalicular network (OLCN) of cortical bone. In contrast, S. aureus intracellular persistence in bone cells has not been substantiated in vivo, which challenges this mode of chronic osteomyelitis. There have also been major advances in our understanding of the immune proteome against S. aureus, from clinical studies of serum antibodies and media enriched for newly synthesized antibodies (MENSA), which may provide new opportunities for osteomyelitis diagnosis, prognosis, and vaccine development. Finally, novel therapies such as antimicrobial implant coatings and antibiotic impregnated 3D-printed scaffolds represent promising strategies for preventing and managing this devastating disease. Here, we review these recent advances and highlight translational opportunities towards a cure.
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Affiliation(s)
- Elysia A Masters
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,2Department of Biomedical Engineering, University of Rochester Medical Center, Rochester, NY USA
| | - Ryan P Trombetta
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,2Department of Biomedical Engineering, University of Rochester Medical Center, Rochester, NY USA
| | - Karen L de Mesy Bentley
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,3Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY USA.,4Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY USA
| | - Brendan F Boyce
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,3Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY USA
| | - Ann Lindley Gill
- 5Department of Microbiology & Immunology, University of Rochester Medical Center, Rochester, NY USA
| | - Steven R Gill
- 5Department of Microbiology & Immunology, University of Rochester Medical Center, Rochester, NY USA
| | - Kohei Nishitani
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,6Department of Orthopaedic Surgery, Kyoto University, Kyoto, Japan
| | - Masahiro Ishikawa
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,6Department of Orthopaedic Surgery, Kyoto University, Kyoto, Japan
| | - Yugo Morita
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,6Department of Orthopaedic Surgery, Kyoto University, Kyoto, Japan
| | - Hiromu Ito
- 6Department of Orthopaedic Surgery, Kyoto University, Kyoto, Japan
| | - Sheila N Bello-Irizarry
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA
| | - Mark Ninomiya
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA
| | - James D Brodell
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA
| | - Charles C Lee
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA
| | - Stephanie P Hao
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA
| | - Irvin Oh
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,4Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY USA
| | - Chao Xie
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,4Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY USA
| | - Hani A Awad
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,2Department of Biomedical Engineering, University of Rochester Medical Center, Rochester, NY USA.,4Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY USA
| | - John L Daiss
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,4Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY USA
| | - John R Owen
- 7Department of Orthopaedic Surgery, Virginia Commonwealth University Medical Center, Richmond, VA USA
| | - Stephen L Kates
- 7Department of Orthopaedic Surgery, Virginia Commonwealth University Medical Center, Richmond, VA USA
| | - Edward M Schwarz
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,2Department of Biomedical Engineering, University of Rochester Medical Center, Rochester, NY USA.,3Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, NY USA.,4Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY USA.,5Department of Microbiology & Immunology, University of Rochester Medical Center, Rochester, NY USA
| | - Gowrishankar Muthukrishnan
- 1Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, NY USA.,4Department of Orthopaedics, University of Rochester Medical Center, Rochester, NY USA
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31
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Nguyen T, Kim T, Ta HM, Yeo WS, Choi J, Mizar P, Lee SS, Bae T, Chaurasia AK, Kim KK. Targeting Mannitol Metabolism as an Alternative Antimicrobial Strategy Based on the Structure-Function Study of Mannitol-1-Phosphate Dehydrogenase in Staphylococcus aureus. mBio 2019; 10:e02660-18. [PMID: 31289190 PMCID: PMC6623548 DOI: 10.1128/mbio.02660-18] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 06/05/2019] [Indexed: 11/22/2022] Open
Abstract
Mannitol-1-phosphate dehydrogenase (M1PDH) is a key enzyme in Staphylococcus aureus mannitol metabolism, but its roles in pathophysiological settings have not been established. We performed comprehensive structure-function analysis of M1PDH from S. aureus USA300, a strain of community-associated methicillin-resistant S. aureus, to evaluate its roles in cell viability and virulence under pathophysiological conditions. On the basis of our results, we propose M1PDH as a potential antibacterial target. In vitro cell viability assessment of ΔmtlD knockout and complemented strains confirmed that M1PDH is essential to endure pH, high-salt, and oxidative stress and thus that M1PDH is required for preventing osmotic burst by regulating pressure potential imposed by mannitol. The mouse infection model also verified that M1PDH is essential for bacterial survival during infection. To further support the use of M1PDH as an antibacterial target, we identified dihydrocelastrol (DHCL) as a competitive inhibitor of S. aureus M1PDH (SaM1PDH) and confirmed that DHCL effectively reduces bacterial cell viability during host infection. To explain physiological functions of SaM1PDH at the atomic level, the crystal structure of SaM1PDH was determined at 1.7-Å resolution. Structure-based mutation analyses and DHCL molecular docking to the SaM1PDH active site followed by functional assay identified key residues in the active site and provided the action mechanism of DHCL. Collectively, we propose SaM1PDH as a target for antibiotic development based on its physiological roles with the goals of expanding the repertory of antibiotic targets to fight antimicrobial resistance and providing essential knowledge for developing potent inhibitors of SaM1PDH based on structure-function studies.IMPORTANCE Due to the shortage of effective antibiotics against drug-resistant Staphylococcus aureus, new targets are urgently required to develop next-generation antibiotics. We investigated mannitol-1-phosphate dehydrogenase of S. aureus USA300 (SaM1PDH), a key enzyme regulating intracellular mannitol levels, and explored the possibility of using SaM1PDH as a target for developing antibiotic. Since mannitol is necessary for maintaining the cellular redox and osmotic potential, the homeostatic imbalance caused by treatment with a SaM1PDH inhibitor or knockout of the gene encoding SaM1PDH results in bacterial cell death through oxidative and/or mannitol-dependent cytolysis. We elucidated the molecular mechanism of SaM1PDH and the structural basis of substrate and inhibitor recognition by enzymatic and structural analyses of SaM1PDH. Our results strongly support the concept that targeting of SaM1PDH represents an alternative strategy for developing a new class of antibiotics that cause bacterial cell death not by blocking key cellular machinery but by inducing cytolysis and reducing stress tolerance through inhibition of the mannitol pathway.
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Affiliation(s)
- Thanh Nguyen
- Department of Molecular Cell Biology, Institute for Antimicrobial Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, South Korea
| | - Truc Kim
- Department of Molecular Cell Biology, Institute for Antimicrobial Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, South Korea
| | - Hai Minh Ta
- Department of Molecular Cell Biology, Institute for Antimicrobial Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, South Korea
| | - Won Sik Yeo
- Department of Microbiology and Immunology, Indiana University School of Medicine Northwest, Gary, Indiana, USA
| | - Jongkeun Choi
- Department of Chemical Engineering, Chungwoon University, Incheon, South Korea
| | - Pushpak Mizar
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Seung Seo Lee
- School of Chemistry, University of Southampton, Southampton, United Kingdom
| | - Taeok Bae
- Department of Microbiology and Immunology, Indiana University School of Medicine Northwest, Gary, Indiana, USA
| | - Akhilesh Kumar Chaurasia
- Department of Molecular Cell Biology, Institute for Antimicrobial Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, South Korea
| | - Kyeong Kyu Kim
- Department of Molecular Cell Biology, Institute for Antimicrobial Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, South Korea
- Samsung Biomedical Research Institute, Samsung Advanced Institute for Health Sciences and Technology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
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32
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Kang J, Dietz MJ, Li B. Antimicrobial peptide LL-37 is bactericidal against Staphylococcus aureus biofilms. PLoS One 2019; 14:e0216676. [PMID: 31170191 PMCID: PMC6553709 DOI: 10.1371/journal.pone.0216676] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 04/26/2019] [Indexed: 11/19/2022] Open
Abstract
Our current challenge in the management of prosthetic joint infection is the eradication of biofilms which has driven the need for improved antimicrobial agents and regimens. In this study, the antimicrobial peptide, LL-37, and silver nanoparticles (AgNPs) were investigated for their antimicrobial efficacies against Staphylococcus aureus (S. aureus), a microorganism commonly implicated in biofilm-related infections. These antimicrobials were compared to conventional antibiotics and combination treatments with rifampin. Using a Centers for Disease Control reactor, 24 h S. aureus biofilms were formed on cobalt-chromium discs and the anti-biofilm activity was determined by quantifying the amount of colony forming units following treatments. We found that LL-37 was the most efficacious antimicrobial agent with a more than 4 log reduction in colony counts. In comparison, silver nanoparticles and conventional antibiotics were not as efficacious, with a less than 1 log reduction in colony counts. Antimicrobial combination treatments with rifampin significantly increased the log reduction for AgNPs and gentamicin, although still significantly less than LL-37 in isolation. Furthermore, kinetic studies revealed the rapid elimination of S. aureus biofilm with LL-37. Collectively, the results of this study demonstrated that LL-37 was an effective agent against S. aureus biofilms and may have potential clinical applications in the eradication of biofilms and treatment of prosthetic joint infection.
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Affiliation(s)
- Jason Kang
- Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV, United States of America
| | - Matthew J. Dietz
- Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV, United States of America
- * E-mail: (MJD); (BL)
| | - Bingyun Li
- Department of Orthopaedics, School of Medicine, West Virginia University, Morgantown, WV, United States of America
- * E-mail: (MJD); (BL)
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33
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Gannoun-Zaki L, Pätzold L, Huc-Brandt S, Baronian G, Elhawy MI, Gaupp R, Martin M, Blanc-Potard AB, Letourneur F, Bischoff M, Molle V. PtpA, a secreted tyrosine phosphatase from Staphylococcus aureus, contributes to virulence and interacts with coronin-1A during infection. J Biol Chem 2018; 293:15569-15580. [PMID: 30131335 DOI: 10.1074/jbc.ra118.003555] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 08/16/2018] [Indexed: 11/06/2022] Open
Abstract
Secretion of bacterial signaling proteins and adaptation to the host, especially during infection, are processes that are often linked in pathogenic bacteria. The human pathogen Staphylococcus aureus is equipped with a large arsenal of immune-modulating factors, allowing it to either subvert the host immune response or to create permissive niches for its survival. Recently, we showed that one of the low-molecular-weight protein tyrosine phosphatases produced by S. aureus, PtpA, is secreted during growth. Here, we report that deletion of ptpA in S. aureus affects intramacrophage survival and infectivity. We also observed that PtpA is secreted during macrophage infection. Immunoprecipitation assays identified several host proteins as putative intracellular binding partners for PtpA, including coronin-1A, a cytoskeleton-associated protein that is implicated in a variety of cellular processes. Of note, we demonstrated that coronin-1A is phosphorylated on tyrosine residues upon S. aureus infection and that its phosphorylation profile is linked to PtpA expression. Our results confirm that PtpA has a critical role during infection as a bacterial effector protein that counteracts host defenses.
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Affiliation(s)
- Laila Gannoun-Zaki
- From the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS, UMR 5235, Montpellier 34000, France and
| | - Linda Pätzold
- the Institute of Medical Microbiology and Hygiene, University of Saarland, 66421 Homburg/Saar, Germany
| | - Sylvaine Huc-Brandt
- From the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS, UMR 5235, Montpellier 34000, France and
| | - Grégory Baronian
- From the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS, UMR 5235, Montpellier 34000, France and
| | - Mohamed Ibrahem Elhawy
- the Institute of Medical Microbiology and Hygiene, University of Saarland, 66421 Homburg/Saar, Germany
| | - Rosmarie Gaupp
- the Institute of Medical Microbiology and Hygiene, University of Saarland, 66421 Homburg/Saar, Germany
| | - Marianne Martin
- From the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS, UMR 5235, Montpellier 34000, France and
| | - Anne-Béatrice Blanc-Potard
- From the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS, UMR 5235, Montpellier 34000, France and
| | - François Letourneur
- From the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS, UMR 5235, Montpellier 34000, France and
| | - Markus Bischoff
- the Institute of Medical Microbiology and Hygiene, University of Saarland, 66421 Homburg/Saar, Germany
| | - Virginie Molle
- From the Laboratoire de Dynamique des Interactions Membranaires Normales et Pathologiques, Université de Montpellier, CNRS, UMR 5235, Montpellier 34000, France and
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34
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Jung M, Shim S, Im YB, Park WB, Yoo HS. Global gene-expression profiles of intracellular survival of the BruAb2_1031 gene mutated Brucella abortus in professional phagocytes, RAW 264.7 cells. BMC Microbiol 2018; 18:82. [PMID: 30064361 PMCID: PMC6069796 DOI: 10.1186/s12866-018-1223-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 07/19/2018] [Indexed: 01/18/2023] Open
Abstract
Background Since recognizing the interaction between Brucella and host cells is crucial to the elucidation of the infectious process, Brucella researches have prioritized the investigation of genes related to pathogenicity. To demonstrate the roles of Brucella genes, RAW 264.7 cells were infected with the Brucella abortus wild-type and mutant strains (generated using transposon mutagenesis), after which the different transcriptional responses of the infected cells were determined using microarray. Results Following infection, enhanced strategies for intracellular survival, such as down-regulation of genes associated with cytokine responses and apoptosis, were observed in RAW 264.7 cells infected with C3 mutant strain when compared to the transcriptional responses of wild-type infected cells. Using sequence analysis, we determined the mutation site of a C3 mutant strain as the ATP-binding cassette transporter permease (BruAb2_1031). These results were evidenced by an increased level of intracellular survival of the C3 mutant strain. Conclusions Characteristics of each mutant strain including bacterial growth rate, abilities to induce cytokine production in macrophages after infection, internalization, and levels of intracellular survival and replication, were investigated by performing RAW 264.7 cell infection experiments. Our results indicate that the BruAb2_1031 gene might be closely related with intracellular survival of B. abortus in RAW 264.7 cells. Electronic supplementary material The online version of this article (10.1186/s12866-018-1223-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Myunghwan Jung
- Department of Infectious Diseases, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.,Present address: Department of Microbiology, Research Institute of Life Sciences, Gyeongsang National University School of Medicine, Jinju, 52727, Republic of Korea
| | - Soojin Shim
- Department of Infectious Diseases, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Young Bin Im
- Department of Infectious Diseases, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Woo Bin Park
- Department of Infectious Diseases, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Han Sang Yoo
- Department of Infectious Diseases, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea. .,Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, Republic of Korea.
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35
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Brandt SL, Putnam NE, Cassat JE, Serezani CH. Innate Immunity to Staphylococcus aureus: Evolving Paradigms in Soft Tissue and Invasive Infections. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 200:3871-3880. [PMID: 29866769 PMCID: PMC6028009 DOI: 10.4049/jimmunol.1701574] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 03/12/2018] [Indexed: 01/18/2023]
Abstract
Staphylococcus aureus causes a wide range of diseases that together embody a significant public health burden. Aided by metabolic flexibility and a large virulence repertoire, S. aureus has the remarkable ability to hematogenously disseminate and infect various tissues, including skin, lung, heart, and bone, among others. The hallmark lesions of invasive staphylococcal infections, abscesses, simultaneously denote the powerful innate immune responses to tissue invasion as well as the ability of staphylococci to persist within these lesions. In this article, we review the innate immune responses to S. aureus during infection of skin and bone, which serve as paradigms for soft tissue and bone disease, respectively.
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Affiliation(s)
- Stephanie L Brandt
- Division of Infectious Disease, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Nicole E Putnam
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232
| | - James E Cassat
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232;
- Division of Infectious Diseases, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232
- Vanderbilt Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN 37232; and
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN 37232
| | - C Henrique Serezani
- Division of Infectious Disease, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232;
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232
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36
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Shupp AB, Kolb AD, Mukhopadhyay D, Bussard KM. Cancer Metastases to Bone: Concepts, Mechanisms, and Interactions with Bone Osteoblasts. Cancers (Basel) 2018; 10:E182. [PMID: 29867053 PMCID: PMC6025347 DOI: 10.3390/cancers10060182] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 05/29/2018] [Accepted: 05/31/2018] [Indexed: 12/31/2022] Open
Abstract
The skeleton is a unique structure capable of providing support for the body. Bone resorption and deposition are controlled in a tightly regulated balance between osteoblasts and osteoclasts with no net bone gain or loss. However, under conditions of disease, the balance between bone resorption and deposition is upset. Osteoblasts play an important role in bone homeostasis by depositing new bone osteoid into resorption pits. It is becoming increasingly evident that osteoblasts additionally play key roles in cancer cell dissemination to bone and subsequent metastasis. Our laboratory has evidence that when osteoblasts come into contact with disseminated breast cancer cells, the osteoblasts produce factors that initially reduce breast cancer cell proliferation, yet promote cancer cell survival in bone. Other laboratories have demonstrated that osteoblasts both directly and indirectly contribute to dormant cancer cell reactivation in bone. Moreover, we have demonstrated that osteoblasts undergo an inflammatory stress response in late stages of breast cancer, and produce inflammatory cytokines that are maintenance and survival factors for breast cancer cells and osteoclasts. Advances in understanding interactions between osteoblasts, osteoclasts, and bone metastatic cancer cells will aid in controlling and ultimately preventing cancer cell metastasis to bone.
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Affiliation(s)
- Alison B Shupp
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | - Alexus D Kolb
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | - Dimpi Mukhopadhyay
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | - Karen M Bussard
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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37
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Sutrisno L, Wang S, Li M, Luo Z, Wang C, Shen T, Chen P, Yang L, Hu Y, Cai K. Construction of three-dimensional net-like polyelectrolyte multilayered nanostructures onto titanium substrates for combined antibacterial and antioxidant applications. J Mater Chem B 2018; 6:5290-5302. [DOI: 10.1039/c8tb00192h] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Fabrication of nanofibers and a bacteria-triggered antibiotic-releasing coating to modify titanium substrates for antibacterial and antioxidant applications.
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38
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Horn J, Stelzner K, Rudel T, Fraunholz M. Inside job: Staphylococcus aureus host-pathogen interactions. Int J Med Microbiol 2017; 308:607-624. [PMID: 29217333 DOI: 10.1016/j.ijmm.2017.11.009] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/17/2017] [Accepted: 11/21/2017] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus is a notorious opportunistic pathogen causing a plethora of diseases. Recent research established that once phagocytosed by neutrophils and macrophages, a certain percentage of S. aureus is able to survive within these phagocytes which thereby even may contribute to dissemination of the pathogen. S. aureus further induces its uptake by otherwise non-phagocytic cells and the ensuing intracellular cytotoxicity is suggested to lead to tissue destruction, whereas bacterial persistence within cells is thought to lead to immune evasion and chronicity of infections. We here review recent work on the S. aureus host pathogen interactions with a focus on the intracellular survival of the pathogen.
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Affiliation(s)
- Jessica Horn
- Chair of Microbiology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Kathrin Stelzner
- Chair of Microbiology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Thomas Rudel
- Chair of Microbiology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Martin Fraunholz
- Chair of Microbiology, Biocenter, University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
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39
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Sabaté Brescó M, Harris LG, Thompson K, Stanic B, Morgenstern M, O'Mahony L, Richards RG, Moriarty TF. Pathogenic Mechanisms and Host Interactions in Staphylococcus epidermidis Device-Related Infection. Front Microbiol 2017; 8:1401. [PMID: 28824556 PMCID: PMC5539136 DOI: 10.3389/fmicb.2017.01401] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 07/11/2017] [Indexed: 12/25/2022] Open
Abstract
Staphylococcus epidermidis is a permanent member of the normal human microbiota, commonly found on skin and mucous membranes. By adhering to tissue surface moieties of the host via specific adhesins, S. epidermidis is capable of establishing a lifelong commensal relationship with humans that begins early in life. In its role as a commensal organism, S. epidermidis is thought to provide benefits to human host, including out-competing more virulent pathogens. However, largely due to its capacity to form biofilm on implanted foreign bodies, S. epidermidis has emerged as an important opportunistic pathogen in patients receiving medical devices. S. epidermidis causes approximately 20% of all orthopedic device-related infections (ODRIs), increasing up to 50% in late-developing infections. Despite this prevalence, it remains underrepresented in the scientific literature, in particular lagging behind the study of the S. aureus. This review aims to provide an overview of the interactions of S. epidermidis with the human host, both as a commensal and as a pathogen. The mechanisms retained by S. epidermidis that enable colonization of human skin as well as invasive infection, will be described, with a particular focus upon biofilm formation. The host immune responses to these infections are also described, including how S. epidermidis seems to trigger low levels of pro-inflammatory cytokines and high levels of interleukin-10, which may contribute to the sub-acute and persistent nature often associated with these infections. The adaptive immune response to S. epidermidis remains poorly described, and represents an area which may provide significant new discoveries in the coming years.
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Affiliation(s)
- Marina Sabaté Brescó
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland.,Molecular Immunology, Swiss Institute of Allergy and Asthma Research, University of ZurichDavos, Switzerland
| | - Llinos G Harris
- Microbiology and Infectious Diseases, Institute of Life Science, Swansea University Medical SchoolSwansea, United Kingdom
| | - Keith Thompson
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
| | - Barbara Stanic
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
| | - Mario Morgenstern
- Department of Orthopedic and Trauma Surgery, University Hospital BaselBasel, Switzerland
| | - Liam O'Mahony
- Molecular Immunology, Swiss Institute of Allergy and Asthma Research, University of ZurichDavos, Switzerland
| | - R Geoff Richards
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
| | - T Fintan Moriarty
- Musculoskeletal Infection, AO Research Institute DavosDavos, Switzerland
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40
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Thymus vulgaris L. and thymol assist murine macrophages (RAW 264.7) in the control of in vitro infections by Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. Immunol Res 2017; 65:932-943. [DOI: 10.1007/s12026-017-8933-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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41
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de Mesy Bentley KL, Trombetta R, Nishitani K, Bello-Irizarry SN, Ninomiya M, Zhang L, Chung HL, McGrath JL, Daiss JL, Awad HA, Kates SL, Schwarz EM. Evidence of Staphylococcus Aureus Deformation, Proliferation, and Migration in Canaliculi of Live Cortical Bone in Murine Models of Osteomyelitis. J Bone Miner Res 2017; 32:985-990. [PMID: 27933662 PMCID: PMC5413415 DOI: 10.1002/jbmr.3055] [Citation(s) in RCA: 165] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 12/02/2016] [Accepted: 12/05/2016] [Indexed: 11/08/2022]
Abstract
Although Staphylococcus aureus osteomyelitis is considered to be incurable, the major bacterial reservoir in live cortical bone has remained unknown. In addition to biofilm bacteria on necrotic tissue and implants, studies have implicated intracellular infection of osteoblasts and osteocytes as a mechanism of chronic osteomyelitis. Thus, we performed the first systematic transmission electron microscopy (TEM) studies to formally define major reservoirs of S. aureus in chronically infected mouse (Balb/c J) long bone tissue. Although rare, evidence of colonized osteoblasts was found. In contrast, we readily observed S. aureus within canaliculi of live cortical bone, which existed as chains of individual cocci and submicron rod-shaped bacteria leading to biofilm formation in osteocyte lacunae. As these observations do not conform to the expectations of S. aureus as non-motile cocci 1.0 to 1.5 μm in diameter, we also performed immunoelectron microscopy (IEM) following in vivo BrdU labeling to assess the role of bacterial proliferation in canalicular invasion. The results suggest that the deformed bacteria: (1) enter canaliculi via asymmetric binary fission; and (2) migrate toward osteocyte lacunae via proliferation at the leading edge. Additional in vitro studies confirmed S. aureus migration through a 0.5-μm porous membrane. Collectively, these findings define a novel mechanism of bone infection, and provide possible new insight as to why S. aureus implant-related infections of bone tissue are so challenging to treat. © 2016 American Society for Bone and Mineral Research.
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Affiliation(s)
- Karen L de Mesy Bentley
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Pathology & Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Orthopaedics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Ryan Trombetta
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Biomedical Engineering, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Kohei Nishitani
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | | | - Mark Ninomiya
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Longze Zhang
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Hung Li Chung
- Department of Biomedical Engineering, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - James L McGrath
- Department of Biomedical Engineering, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - John L Daiss
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Hani A Awad
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Biomedical Engineering, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Stephen L Kates
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Orthopaedic Surgery, Virginia Commonwealth University Medical Center, Richmond, VA, USA
| | - Edward M Schwarz
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Pathology & Laboratory Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Orthopaedics, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.,Department of Biomedical Engineering, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
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42
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Armstead AL, Simoes TA, Wang X, Brydson R, Brown A, Jiang BH, Rojanasakul Y, Li B. Toxicity and oxidative stress responses induced by nano- and micro-CoCrMo particles. J Mater Chem B 2017. [DOI: 10.1039/c7tb01372h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Particles on the nano- and micro-meter scales present unique cell-specific cellular effects (i.e.cytotoxicity and oxidative stress).
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Affiliation(s)
- Andrea L. Armstead
- Department of Orthopaedics
- School of Medicine
- West Virginia University
- Morgantown
- USA
| | - Thiago A. Simoes
- Institute for Materials Research
- School of Chemical and Process Engineering
- University of Leeds
- UK
| | - Xianfeng Wang
- Department of Orthopaedics
- School of Medicine
- West Virginia University
- Morgantown
- USA
| | - Rik Brydson
- Institute for Materials Research
- School of Chemical and Process Engineering
- University of Leeds
- UK
| | - Andy Brown
- Institute for Materials Research
- School of Chemical and Process Engineering
- University of Leeds
- UK
| | - Bing-Hua Jiang
- Department of Pathology
- Anatomy and Cell Biology
- Thomas Jefferson University
- Philadelphia
- USA
| | - Yon Rojanasakul
- School of Pharmacy
- West Virginia University
- Morgantown
- USA
- Mary Babb Randolph Cancer Center
| | - Bingyun Li
- Department of Orthopaedics
- School of Medicine
- West Virginia University
- Morgantown
- USA
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43
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McLoughlin A, Rochfort KD, McDonnell CJ, Kerrigan SW, Cummins PM. Staphylococcus aureus-mediated blood-brain barrier injury: an in vitro human brain microvascular endothelial cell model. Cell Microbiol 2016; 19. [PMID: 27598716 DOI: 10.1111/cmi.12664] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 12/17/2022]
Abstract
Blood-brain barrier (BBB) disruption constitutes a hallmark event during pathogen-mediated neurological disorders such as bacterial meningitis. As a prevalent opportunistic pathogen, Staphylococcus aureus (SA) is of particular interest in this context, although our fundamental understanding of how SA disrupts the BBB is very limited. This paper employs in vitro infection models to address this. Human brain microvascular endothelial cells (HBMvECs) were infected with formaldehyde-fixed (multiplicity of infection [MOI] 0-250, 0-48 hr) and live (MOI 0-100, 0-3 hr) SA cultures. Both Fixed-SA and Live-SA could adhere to HBMvECs with equal efficacy and cause elevated paracellular permeability. In further studies employing Fixed-SA, infection of HBMvECs caused dose-dependent release of cytokines/chemokines (TNF-α, IL-6, MCP-1, IP-10, and thrombomodulin), reduced expression of interendothelial junction proteins (VE-Cadherin, claudin-5, and ZO-1), and activation of both canonical and non-canonical NF-κB pathways. Using N-acetylcysteine, we determined that these events were coupled to the SA-mediated induction of reactive oxygen species (ROS) within HBMvECs. Finally, treatment of HBMvECs with Fixed-ΔSpA (MOI 0-250, 48 hr), a gene deletion mutant of Staphylococcal protein A associated with bacterial infectivity, had relatively similar effects to Newman WT Fixed-SA. In conclusion, these findings provide insight into how SA infection may activate proinflammatory mechanisms within the brain microvascular endothelium to elicit BBB failure.
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Affiliation(s)
| | - Keith D Rochfort
- School of Biotechnology, Dublin City University, Dublin, Ireland
| | - Cormac J McDonnell
- Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, 123 St. Stephens Green, Dublin, Ireland
| | - Steven W Kerrigan
- Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, 123 St. Stephens Green, Dublin, Ireland
| | - Philip M Cummins
- School of Biotechnology, Dublin City University, Dublin, Ireland
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Collaborative Interferon-γ and Interleukin-17 Signaling Protects the Oral Mucosa from Staphylococcus aureus. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:2337-52. [PMID: 27470712 DOI: 10.1016/j.ajpath.2016.07.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Infections with Staphylococcus aureus are a continuing and growing problem in community and hospital settings. Preclinical animal modeling of S. aureus relies on experimental infection, which carries some limitations. We describe here a novel, spontaneous model of oral staphylococcal infection in double knockout mice, deficient in the receptors for IL-17 (IL-17RA) and interferon (IFN)-γ (IFNγRI), beginning at 6 to 8 weeks of age. IFNγRI(-/-)IL17RA(-/-) (GRAKO) mice developed progressive oral abscesses. Cytometric methods revealed extensive neutrophilic infiltration of oral tissues in GRAKO mice; further investigation evidenced that IL-17 predominated neutrophil defects in these mice. To investigate the contribution of IFN-γ signaling to this native host defense to S. aureus, we observed perturbations of monocyte recruitment and macrophage differentiation in the oral tissues of GRAKO mice, and CXCL9/chemokine ligand receptor (CXCR)3-driven recruitment of T-cell oral tissues and draining lymph nodes. To address the former finding, we depleted macrophages and monocytes in vivo from IL17RA(-/-) mice using liposomes loaded with clodronate. This treatment elicited oral abscesses, recapitulating the phenotype of GRAKO mice. From these findings, we propose novel collaborative functions of IL-17 and IFN-γ, acting through neutrophils and macrophages, respectively, in native mucocutaneous host defenses to S. aureus.
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Josse J, Guillaume C, Bour C, Lemaire F, Mongaret C, Draux F, Velard F, Gangloff SC. Impact of the Maturation of Human Primary Bone-Forming Cells on Their Behavior in Acute or Persistent Staphylococcus aureus Infection Models. Front Cell Infect Microbiol 2016; 6:64. [PMID: 27446812 PMCID: PMC4914565 DOI: 10.3389/fcimb.2016.00064] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/30/2016] [Indexed: 02/05/2023] Open
Abstract
Staphylococcus aureus is one of the most frequently involved pathogens in bacterial infections such as skin abscess, pneumonia, endocarditis, osteomyelitis, and implant-associated infection. As for bone homeostasis, it is partly altered during infections by S. aureus by the induction of various responses from osteoblasts, which are the bone-forming cells responsible for extracellular matrix synthesis and its mineralization. Nevertheless, bone-forming cells are a heterogeneous population with different stages of maturation and the impact of the latter on their responses toward bacteria remains unclear. We describe the impact of S. aureus on two populations of human primary bone-forming cells (HPBCs) which have distinct maturation characteristics in both acute and persistent models of interaction. Cell maturation did not influence the internalization and survival of S. aureus inside bone-forming cells or the cell death related to the infection. By studying the expression of chemokines, cytokines, and osteoclastogenic regulators by HPBCs, we observed different profiles of chemokine expression according to the degree of cell maturation. However, there was no statistical difference in the amounts of proteins released by both populations in the presence of S. aureus compared to the non-infected counterparts. Our findings show that cell maturation does not impact the behavior of HPBCs infected with S. aureus and suggest that the role of bone-forming cells may not be pivotal for the inflammatory response in osteomyelitis.
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Affiliation(s)
- Jérôme Josse
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-ArdenneReims, France; UFR Pharmacie, Pôle Santé, Université de Reims Champagne-ArdenneReims, France
| | - Christine Guillaume
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-ArdenneReims, France; UFR Odontologie, Pôle Santé, Université de Reims Champagne-ArdenneReims, France
| | - Camille Bour
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-Ardenne Reims, France
| | - Flora Lemaire
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-Ardenne Reims, France
| | - Céline Mongaret
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-ArdenneReims, France; UFR Pharmacie, Pôle Santé, Université de Reims Champagne-ArdenneReims, France
| | - Florence Draux
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-ArdenneReims, France; UFR Odontologie, Pôle Santé, Université de Reims Champagne-ArdenneReims, France
| | - Frédéric Velard
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-ArdenneReims, France; UFR Odontologie, Pôle Santé, Université de Reims Champagne-ArdenneReims, France
| | - Sophie C Gangloff
- EA 4691 ≪Biomatériaux et Inflammation en Site Osseux ≫, Pôle Santé, Université de Reims Champagne-ArdenneReims, France; UFR Pharmacie, Pôle Santé, Université de Reims Champagne-ArdenneReims, France
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Yajjala VK, Thomas VC, Bauer C, Scherr TD, Fischer KJ, Fey PD, Bayles KW, Kielian T, Sun K. Resistance to Acute Macrophage Killing Promotes Airway Fitness of Prevalent Community-Acquired Staphylococcus aureus Strains. THE JOURNAL OF IMMUNOLOGY 2016; 196:4196-203. [PMID: 27053759 DOI: 10.4049/jimmunol.1600081] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 03/13/2016] [Indexed: 11/19/2022]
Abstract
The incidence of methicillin-resistant Staphylococcus aureus (MRSA) pneumonia in otherwise healthy individuals is increasing. To investigate the mechanism underlying the epidemiological success of predominant community-associated (CA)-MRSA strains, we examined their fitness traits during the initial interaction between bacteria and the host occurring in the lower airway. Using a mouse respiratory infection model, we show that clinical isolates often responsible for CA infections are highly resistant to clearance from healthy airways, whereas S. aureus strains not as prevalent or traditionally associated with hospital-associated infections are relatively susceptible. Mechanistically, the competitive fitness of S. aureus is a result of both agr-dependent and -independent resistance to innate bacterial killing. Furthermore, we show that rather than evasion from neutrophil-dependent bactericidal process, the observed S. aureus fitness in the lower airways is due to its intrinsic resistance to resident alveolar macrophage-mediated intracellular killing. Importantly, we demonstrate that the virulence determinants responsible for bacterial persistence in immune-competent mice are dispensable in mice with predisposing conditions such as influenza infection. Taken together, these novel findings of the improved competence of predominant CA-MRSA strains to survive innate killing in healthy hosts, particularly at the very beginning stage of infection, provide a unique insight into their epidemiological success.
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Affiliation(s)
- Vijaya Kumar Yajjala
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Vinai Chittezham Thomas
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Christopher Bauer
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Tyler D Scherr
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Karl J Fischer
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Paul D Fey
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Kenneth W Bayles
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Keer Sun
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
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47
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Turkovicova L, Smidak R, Jung G, Turna J, Lubec G, Aradska J. Proteomic analysis of the TerC interactome: Novel links to tellurite resistance and pathogenicity. J Proteomics 2016; 136:167-73. [PMID: 26778143 DOI: 10.1016/j.jprot.2016.01.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 12/02/2015] [Accepted: 01/04/2016] [Indexed: 12/18/2022]
Abstract
The tellurite resistance gene operon (ter) is widely spread among bacterial species, particularly pathogenic species. The ter operon has been implicated in tellurite resistance, phage inhibition, colicine resistance, and pathogenicity. The TerC protein represents one of the key proteins in tellurite resistance and shows no significant homology to any protein of known function. So far, there is no experimental evidence for TerC interaction partners. In this study, proteomic-based methods, including blue native electrophoresis and co-immunoprecipitation combined with LC-MS/MS, have been used to identify TerC interaction partners and thus providing indirect evidence for tentative functions of TerC in Escherichia coli. An interactome has been constructed and robust physical interaction of integral membrane protein TerC with TerB, DctA, PspA, HslU, and RplK has been shown. The TerC-TerB complex appears to act as a central unit that may link different functional modules with biochemical activities of C4-dicarboxylate transport, inner membrane stress response (phage shock protein regulatory complex), ATPase/chaperone activity, and proteosynthesis. In previous reports, it was hypothesized that a transmembrane unit formed by TerC protein may interact with the TerD family, but herein neither TerD nor TerE proteins were identified as TerC complex components. We propose that TerD/TerE participates in tellurite resistance through TerC-independent action.
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Affiliation(s)
- L Turkovicova
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria; Department of Molecular Biology, Faculty of Natural Science, Comenius University, Bratislava, Slovakia
| | - R Smidak
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | - G Jung
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria
| | - J Turna
- Department of Molecular Biology, Faculty of Natural Science, Comenius University, Bratislava, Slovakia
| | - G Lubec
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria.
| | - J Aradska
- Department of Pediatrics, Medical University of Vienna, Vienna, Austria.
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48
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Josse J, Velard F, Gangloff SC. Staphylococcus aureus vs. Osteoblast: Relationship and Consequences in Osteomyelitis. Front Cell Infect Microbiol 2015; 5:85. [PMID: 26636047 PMCID: PMC4660271 DOI: 10.3389/fcimb.2015.00085] [Citation(s) in RCA: 164] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 11/10/2015] [Indexed: 12/11/2022] Open
Abstract
Bone cells, namely osteoblasts and osteoclasts work in concert and are responsible for bone extracellular matrix formation and resorption. This homeostasis is, in part, altered during infections by Staphylococcus aureus through the induction of various responses from the osteoblasts. This includes the over-production of chemokines, cytokines and growth factors, thus suggesting a role for these cells in both innate and adaptive immunity. S. aureus decreases the activity and viability of osteoblasts, by induction of apoptosis-dependent and independent mechanisms. The tight relationship between osteoclasts and osteoblasts is also modulated by S. aureus infection. The present review provides a survey of the relevant literature discussing the important aspects of S. aureus and osteoblast interaction as well as the ability for antimicrobial peptides to kill intra-osteoblastic S. aureus, hence emphasizing the necessity for new anti-infectious therapeutics.
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Affiliation(s)
- Jérôme Josse
- EA 4691 Biomatériaux et inflammation en site osseux, Pôle Santé, Université de Reims Champagne-Ardenne Reims, France
| | - Frédéric Velard
- EA 4691 Biomatériaux et inflammation en site osseux, Pôle Santé, Université de Reims Champagne-Ardenne Reims, France
| | - Sophie C Gangloff
- EA 4691 Biomatériaux et inflammation en site osseux, Pôle Santé, Université de Reims Champagne-Ardenne Reims, France
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49
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Flannagan RS, Heit B, Heinrichs DE. Intracellular replication of Staphylococcus aureus in mature phagolysosomes in macrophages precedes host cell death, and bacterial escape and dissemination. Cell Microbiol 2015; 18:514-35. [PMID: 26408990 DOI: 10.1111/cmi.12527] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 09/21/2015] [Accepted: 09/22/2015] [Indexed: 01/12/2023]
Abstract
The success of Staphylococcus aureus as a pathogen is partly attributable to its ability to thwart host innate immune responses, which includes resisting the antimicrobial functions of phagocytes. Here, we have studied the interaction of methicillin-resistant S. aureus (MRSA) strain USA300 with murine RAW 264.7 and primary human macrophages using molecular imaging and single cell analysis to obtain an unprecedented understanding of the interaction between the macrophage and MRSA. Herein we demonstrate that macrophages fail to control intracellular infection by MRSA USA300 despite trafficking the bacteria into mature phagolysosomes. Using fluorescence-based proliferation assays we also show that intracellular staphylococci proliferate and that replication commences while the bacteria are residing in mature phagolysosomes hours after initial phagocytosis. Finally, live-cell fluorescence video microscopy allowed for unprecedented visual insight into the escape of MRSA from macrophages, demonstrating that the macrophages die through a pathway characterized by membrane blebbing and activation of caspase-3 followed by acquisition of the vital dye propidium iodide. Moreover, cell death precedes the emergence of MRSA from infected macrophages, and these events can be ablated by prolonged exposure of infected phagocytes to gentamicin.
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Affiliation(s)
- Ronald S Flannagan
- Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada, N6A 5C1
| | - Bryan Heit
- Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada, N6A 5C1.,Centre for Human Immunology, The University of Western Ontario, London, Ontario, Canada, N6A 5C1
| | - David E Heinrichs
- Department of Microbiology and Immunology, The University of Western Ontario, London, Ontario, Canada, N6A 5C1.,Centre for Human Immunology, The University of Western Ontario, London, Ontario, Canada, N6A 5C1
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50
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Abstract
Skin is the most common site of Staphylococcus aureus infection. While most of these infections are self-limited, recurrent infections are common. Keratinocytes and recruited immune cells participate in skin defense against infection. We postulated that S. aureus is able to adapt to the milieu within human keratinocytes to avoid keratinocyte-mediated clearance. From a collection of S. aureus isolated from chronically infected patients with atopic dermatitis, we noted 22% had an agr mutant-like phenotype. Using several models of human skin infection, we demonstrate that toxin-deficient, agr mutants of methicillin-resistant S. aureus (MRSA) USA300 are able to persist within keratinocytes by stimulating autophagy and evading caspase-1 and inflammasome activation. MRSA infection induced keratinocyte autophagy, as evidenced by galectin-8 and LC3 accumulation. Autophagy promoted the degradation of inflammasome components and facilitated staphylococcal survival. The recovery of more than 58% agr or RNAIII mutants (P < 0.0001) of an inoculum of wild-type (WT) MRSA from within wortmannin-treated keratinocytes compared to control keratinocytes reflected the survival advantage for mutants no longer expressing agr-dependent toxins. Our results illustrate the dynamic interplay between S. aureus and keratinocytes that can result in the selection of mutants that have adapted specifically to evade keratinocyte-mediated clearance mechanisms. Human skin is a major site of staphylococcal infection, and keratinocytes actively participate in eradication of these pathogens. We demonstrate that methicillin-resistant Staphylococcus aureus (MRSA) is ingested by keratinocytes and activates caspase-1-mediated clearance through pyroptosis. Toxin-deficient MRSA mutants are selected within keratinocytes that fail to induce caspase-1 activity and keratinocyte-mediated clearance. These intracellular staphylococci induce autophagy that enhances their intracellular survival by diminishing inflammasome components. These findings suggest that S. aureus mutants, by exploiting autophagy, can persist within human keratinocytes.
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