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Nowotnick AG, Xi Z, Jin Z, Khalatbarizamanpoor S, Brauer DS, Löffler B, Jandt KD. Antimicrobial Biomaterials Based on Physical and Physicochemical Action. Adv Healthc Mater 2024:e2402001. [PMID: 39301968 DOI: 10.1002/adhm.202402001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 08/09/2024] [Indexed: 09/22/2024]
Abstract
Developing effective antimicrobial biomaterials is a relevant and fast-growing field in advanced healthcare materials. Several well-known (e.g., traditional antibiotics, silver, copper etc.) and newer (e.g., nanostructured, chemical, biomimetic etc.) approaches have been researched and developed in recent years and valuable knowledge has been gained. However, biomaterials associated infections (BAIs) remain a largely unsolved problem and breakthroughs in this area are sparse. Hence, novel high risk and potential high gain approaches are needed to address the important challenge of BAIs. Antibiotic free antimicrobial biomaterials that are largely based on physical action are promising, since they reduce the risk of antibiotic resistance and tolerance. Here, selected examples are reviewed such antimicrobial biomaterials, namely switchable, protein-based, carbon-based and bioactive glass, considering microbiological aspects of BAIs. The review shows that antimicrobial biomaterials mainly based on physical action are powerful tools to control microbial growth at biomaterials interfaces. These biomaterials have major clinical and application potential for future antimicrobial healthcare materials without promoting microbial tolerance. It also shows that the antimicrobial action of these materials is based on different complex processes and mechanisms, often on the nanoscale. The review concludes with an outlook and highlights current important research questions in antimicrobial biomaterials.
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Affiliation(s)
- Adrian G Nowotnick
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
- Jena School for Microbial Communication (JSMC), 07743, Neugasse 23, Jena, Germany
| | - Zhongqian Xi
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
- Jena School for Microbial Communication (JSMC), 07743, Neugasse 23, Jena, Germany
| | - Zhaorui Jin
- Bioactive Glasses Group, Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Lessingstraße 12, 07743, Jena, Germany
| | - Sadaf Khalatbarizamanpoor
- Jena School for Microbial Communication (JSMC), 07743, Neugasse 23, Jena, Germany
- Institute of Medical Microbiology, Jena University Hospital, 07747, Am Klinikum 1, Jena, Germany
| | - Delia S Brauer
- Bioactive Glasses Group, Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Lessingstraße 12, 07743, Jena, Germany
| | - Bettina Löffler
- Jena School for Microbial Communication (JSMC), 07743, Neugasse 23, Jena, Germany
- Institute of Medical Microbiology, Jena University Hospital, 07747, Am Klinikum 1, Jena, Germany
| | - Klaus D Jandt
- Chair of Materials Science (CMS), Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
- Jena School for Microbial Communication (JSMC), 07743, Neugasse 23, Jena, Germany
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Giraldo-Osorno PM, Wirsig K, Asa'ad F, Omar O, Trobos M, Bernhardt A, Palmquist A. Macrophage-to-osteocyte communication: Impact in a 3D in vitro implant-associated infection model. Acta Biomater 2024; 186:141-155. [PMID: 39142531 DOI: 10.1016/j.actbio.2024.08.005] [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: 04/23/2024] [Revised: 07/23/2024] [Accepted: 08/04/2024] [Indexed: 08/16/2024]
Abstract
Macrophages and osteocytes are important regulators of inflammation, osteogenesis and osteoclastogenesis. However, their interactions under adverse conditions, such as biomaterial-associated infection (BAI) are not fully understood. We aimed to elucidate how factors released from macrophages modulate osteocyte responses in an in vitro indirect 3D co-culture model. Human monocyte-derived macrophages were cultured on etched titanium disks and activated with either IL-4 cytokine (anti-inflammatory M2 phenotype) or Staphylococcus aureus secreted virulence factors to simulate BAI (pro-inflammatory M1 phenotype). Primary osteocytes in collagen gels were then stimulated with conditioned media (CM) from these macrophages. The osteocyte response was analyzed by gene expression, protein secretion, and immunostaining. M1 phenotype macrophages were confirmed by IL-1β and TNF-α secretion, and M2 macrophages by ARG-1 and MRC-1.Osteocytes receiving M1 CM revealed bone inhibitory effects, denoted by reduced secretion of bone formation osteocalcin (BGLAP) and increased secretion of the bone inhibitory sclerostin (SOST). These osteocytes also downregulated the pro-mineralization gene PHEX and upregulated the anti-mineralization gene MEPE. Additionally, exhibited pro-osteoclastic potential by upregulating pro-osteoclastic gene RANKL expression. Nonetheless, M1-stimulated osteocytes expressed a higher level of the potent pro-osteogenic factor BMP-2 in parallel with the downregulation of the bone inhibitor genes DKK1 and SOST, suggesting a compensatory feedback mechanisms. Conversely, M2-stimulated osteocytes mainly upregulated anti-osteoclastic gene OPG expression, suggesting an anti-catabolic effect. Altogether, our findings demonstrate a strong communication between M1 macrophages and osteocytes under M1 (BAI)-simulated conditions, suggesting that the BAI adverse effects on osteoblastic and osteoclastic processes in vitro are partly mediated via this communication. STATEMENT OF SIGNIFICANCE: Biomaterial-associated infections are major challenges and the underlying mechanisms in the cellular interactions are missing, especially among the major cells from the inflammatory side (macrophages as the key cell in bacterial clearance) and the regenerative side (osteocyte as main regulator of bone). We evaluated the effect of macrophage polarization driven by the stimulation with bacterial virulence factors on the osteocyte function using an indirect co-culture model, hence mimicking the scenario of a biomaterial-associated infection. The results suggest that at least part of the adverse effects of biomaterial associated infection on osteoblastic and osteoclastic processes in vitro are mediated via macrophage-to-osteocyte communication.
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Affiliation(s)
- Paula Milena Giraldo-Osorno
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Katharina Wirsig
- Faculty of Medicine, Centre for Translational Bone, Joint and Soft Tissue Research, Technische Universität Dresden, Germany
| | - Farah Asa'ad
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Oral Biochemistry, Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Omar Omar
- Department of Biomedical Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Margarita Trobos
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anne Bernhardt
- Faculty of Medicine, Centre for Translational Bone, Joint and Soft Tissue Research, Technische Universität Dresden, Germany.
| | - Anders Palmquist
- Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
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Zelmer AR, Yang D, Gunn NJ, Solomon LB, Nelson R, Kidd SP, Richter K, Atkins GJ. Osteomyelitis-relevant antibiotics at clinical concentrations show limited effectivity against acute and chronic intracellular S. aureus infections in osteocytes. Antimicrob Agents Chemother 2024:e0080824. [PMID: 39194210 DOI: 10.1128/aac.00808-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Accepted: 08/09/2024] [Indexed: 08/29/2024] Open
Abstract
Osteomyelitis caused by Staphylococcus aureus can involve the persistent infection of osteocytes. We sought to determine if current clinically utilized antibiotics were capable of clearing an intracellular osteocyte S. aureus infection. Rifampicin, vancomycin, levofloxacin, ofloxacin, amoxicillin, oxacillin, doxycycline, linezolid, gentamicin, and tigecycline were assessed for their minimum inhibitory concentration (MIC) and minimum bactericidal concentrations against 12 S. aureus strains, at pH 5.0 and 7.2 to mimic lysosomal and cytoplasmic environments, respectively. Those antibiotics whose bone estimated achievable concentration was commonly above their respective MIC for the strains tested were further assayed in a human osteocyte infection model under acute and chronic conditions. Osteocyte-like cells were treated at 1×, 4×, and 10× the MIC for 1 and 7 days following infection (acute model), or at 15 and 21 days of infection (chronic model). The intracellular effectivity of each antibiotic was measured in terms of CFU reduction, small colony variant formation, and bacterial mRNA expression change. Only rifampicin, levofloxacin, and linezolid reduced intracellular CFU numbers significantly in the acute model. Consistent with the transition to a non-culturable state, few if any CFU could be recovered from the chronic model. However, no treatment in either model reduced the quantity of bacterial mRNA or prevented non-culturable bacteria from returning to a culturable state. These findings indicate that S. aureus adapts phenotypically during intracellular infection of osteocytes, adopting a reversible quiescent state that is protected against antibiotics, even at 10× their MIC. Thus, new therapeutic approaches are necessary to cure S. aureus intracellular infections in osteomyelitis.
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Affiliation(s)
- Anja R Zelmer
- Center for Orthopedic and Trauma Research, Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, Australia
| | - Dongqing Yang
- Center for Orthopedic and Trauma Research, Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, Australia
| | - Nicholas J Gunn
- Center for Orthopedic and Trauma Research, Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, Australia
| | - L Bogdan Solomon
- Center for Orthopedic and Trauma Research, Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, Australia
- Department of Orthopedics and Trauma, Royal Adelaide Hospital, Adelaide, Australia
| | - Renjy Nelson
- Department of Infectious Diseases, Central Adelaide Local Health Network, Adelaide, Australia
| | - Stephen P Kidd
- Australian Center for Antimicrobial Resistance Ecology, University of Adelaide, Adelaide, Australia
- Research Center for Infectious Disease, School of Biological Science, University of Adelaide, Adelaide, Australia
| | - Katharina Richter
- Department of Surgery, Richter Lab, Basil Hetzel Institute for Translational Health Research, University of Adelaide, Adelaide, Australia
- Institute for Photonics and Advanced Sensing, University of Adelaide, Adelaide, Australia
| | - Gerald J Atkins
- Center for Orthopedic and Trauma Research, Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, Australia
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Young J, Lee SW, Shariyate MJ, Cronin A, Wixted JJ, Nazarian A, Rowley CF, Rodriguez EK. Bacteriophage therapy and current delivery strategies for orthopedic infections: A SCOPING review. J Infect 2024; 88:106125. [PMID: 38373574 DOI: 10.1016/j.jinf.2024.106125] [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: 12/11/2023] [Revised: 02/09/2024] [Accepted: 02/14/2024] [Indexed: 02/21/2024]
Abstract
OBJECTIVES Interest in phages as adjunctive therapy to treat difficult infections has grown in the last decade. However, phage dosing and delivery for orthopedic infections have not been systematically summarized. METHODS Following PRISMA-ScR guidelines, we conducted a SCOPING review through September 1st, 2023, of MEDLINE, Embase, Web of Science Core Collection, and Cochrane Central. RESULTS In total, 77 studies were included, of which 19 (24.7%) were in vitro studies, 17 (22.1%) were animal studies, and 41 (53.2%) were studies in humans. A total of 137 contemporary patients receiving phage therapy are described. CONCLUSIONS Direct phage delivery remains the most studied form of phage therapy, notably in prosthetic joint infections, osteomyelitis, and diabetic foot ulcers. Available evidence describing phage therapy in humans suggests favorable outcomes for orthopedic infections, though this evidence is composed largely of low-level descriptive studies. Several phage delivery devices have been described, though a lack of comparative and in-human evidence limits their therapeutic application. Limitations to the use of phage therapy for orthopedic infections that need to be overcome include a lack of understanding related to optimal dosing and phage pharmacokinetics, bacterial heterogeneity in an infection episode, and phage therapy toxicity.
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Affiliation(s)
- Jason Young
- Harvard Combined Orthopedic Residency Program, Boston, MA, USA; Harvard Medical School, Boston, MA, USA.
| | | | - Mohammad J Shariyate
- Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | | | - John J Wixted
- Harvard Medical School, Boston, MA, USA; Carl J. Shapiro Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Ara Nazarian
- Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA, USA; Carl J. Shapiro Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA, USA; Department of Orthopedic Surgery, Yerevan State Medical University, Yerevan, Armenia
| | - Christopher F Rowley
- Division of Infectious Diseases, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA; Harvard School of Public Health, Boston, MA, USA
| | - Edward K Rodriguez
- Harvard Medical School, Boston, MA, USA; Carl J. Shapiro Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA, USA
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Liu L, Zhao N, Yang K, Liao H, Liu X, Wu Y, Wang Y, Peng X, Wu Y. Proteomic Analysis of Staphylococcus aureus Treated with ShangKeHuangShui. Biol Pharm Bull 2024; 47:292-302. [PMID: 38281773 DOI: 10.1248/bpb.b23-00471] [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] [Indexed: 01/30/2024]
Abstract
Staphylococcus aureus (SAU) stands as the prevailing pathogen in post-traumatic infections, with the emergence of antibiotic resistance presenting formidable treatment hurdles. The pressing need is to explore novel antibiotics to address this challenge. ShangKeHuangShui (SKHS), a patented traditional Chinese herbal formula, has gained widespread use in averting post-traumatic infections, but its biological effects remain incomplete understanding. This study's primary objective was to delve into the antibacterial properties, potential antibacterial compounds within SKHS, and their associated molecular targets. In vitro SKHS antibacterial assays demonstrated that the minimum inhibitory concentration (MIC) was 8.625 mg/mL and the minimum bactericide concentration (MBC) was 17.25 mg/mL. Proteomic analysis based on tandem mass tag (TMT) showed significant changes in the expression level of 246 proteins in SKHS treated group compared to control group, with 79 proteins upregulated and 167 proteins downregulated (>1.5-fold, p < 0.05). Subsequently, thirteen target proteins related to various biological processes and multiple metabolic pathways were selected to conduct parallel reaction monitoring (PRM) and molecular docking screen. In protein tyrosine phosphatase PtpA (ptpA) docking screening, phellodendrine and obacunone can bind to ptpA with the binding energy of - 8.4 and - 8.3 kcal/mol, respectively. This suggests their potential impact on antibacterial activity by modulating the two-component system of SAU. The discovery lays a groundwork for future research endeavors for exploring new antibacterial candidates and elucidating specific active chemical components within SKHS that match target proteins. Further investigations are imperative to unveil the biological effects of these monomers and their potential synergistic actions.
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Affiliation(s)
- Lichu Liu
- Institute of Orthopedics and Traumatology, Foshan Hospital of Traditional Chinese Medicine
| | - Na Zhao
- Institute of Orthopedics and Traumatology, Foshan Hospital of Traditional Chinese Medicine
| | - Kuangyang Yang
- Institute of Orthopedics and Traumatology, Foshan Hospital of Traditional Chinese Medicine
| | - Honghong Liao
- Institute of Orthopedics and Traumatology, Foshan Hospital of Traditional Chinese Medicine
| | - Xiaofang Liu
- Institute of Orthopedics and Traumatology, Foshan Hospital of Traditional Chinese Medicine
| | - Ying Wu
- Laboratory Medicine Center, Foshan Hospital of Traditional Chinese Medicine
| | - Yan Wang
- Center for Translational Medicine Research and Development, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences
| | - Xiao Peng
- Institute of Orthopedics and Traumatology, Foshan Hospital of Traditional Chinese Medicine
| | - Yuanyan Wu
- Institute of Orthopedics and Traumatology, Foshan Hospital of Traditional Chinese Medicine
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Piuzzi NS, Klika AK, Lu Q, Higuera-Rueda CA, Stappenbeck T, Visperas A. Periprosthetic joint infection and immunity: Current understanding of host-microbe interplay. J Orthop Res 2024; 42:7-20. [PMID: 37874328 DOI: 10.1002/jor.25723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 09/19/2023] [Accepted: 10/17/2023] [Indexed: 10/25/2023]
Abstract
Periprosthetic joint infection (PJI) is a major complication of total joint arthroplasty. Even with current treatments, failure rates are unacceptably high with a 5-year mortality rate of 26%. Majority of the literature in the field has focused on development of better biomarkers for diagnostics and treatment strategies including innovate antibiotic delivery systems, antibiofilm agents, and bacteriophages. Nevertheless, the role of the immune system, our first line of defense during PJI, is not well understood. Evidence of infection in PJI patients is found within circulation, synovial fluid, and tissue and include numerous cytokines, metabolites, antimicrobial peptides, and soluble receptors that are part of the PJI diagnosis workup. Macrophages, neutrophils, and myeloid-derived suppressor cells (MDSCs) are initially recruited into the joint by chemokines and cytokines produced by immune cells and bacteria and are activated by pathogen-associated molecular patterns. While these cells are efficient killers of planktonic bacteria by phagocytosis, opsonization, degranulation, and recruitment of adaptive immune cells, biofilm-associated bacteria are troublesome. Biofilm is not only a physical barrier for the immune system but also elicits effector functions. Additionally, bacteria have developed mechanisms to evade the immune system by inactivating effector molecules, promoting killing or anti-inflammatory effector cell phenotypes, and intracellular persistence and dissemination. Understanding these shortcomings and the mechanisms by which bacteria can subvert the immune system may open new approaches to better prepare our own immune system to combat PJI. Furthermore, preoperative immune system assessment and screening for dysregulation may aid in developing preventative interventions to decrease PJI incidence.
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Affiliation(s)
- Nicolas S Piuzzi
- Department of Orthopaedic Surgery, Cleveland Clinic Adult Reconstruction Research (CCARR), Cleveland Clinic, Cleveland, Ohio, USA
- Department of Biomedical Engineering, Cleveland Clinic, Cleveland, Ohio, USA
| | - Alison K Klika
- Department of Orthopaedic Surgery, Cleveland Clinic Adult Reconstruction Research (CCARR), Cleveland Clinic, Cleveland, Ohio, USA
| | - Qiuhe Lu
- Department of Inflammation and Immunity, Cleveland Clinic, Cleveland, Ohio, USA
| | | | | | - Anabelle Visperas
- Department of Orthopaedic Surgery, Cleveland Clinic Adult Reconstruction Research (CCARR), Cleveland Clinic, Cleveland, Ohio, USA
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Friot A, Djebali S, Valsesia S, Parroche P, Dubois M, Baude J, Vandenesch F, Marvel J, Leverrier Y. Antigen specific activation of cytotoxic CD8 + T cells by Staphylococcus aureus infected dendritic cells. Front Cell Infect Microbiol 2023; 13:1245299. [PMID: 37953797 PMCID: PMC10639145 DOI: 10.3389/fcimb.2023.1245299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 09/22/2023] [Indexed: 11/14/2023] Open
Abstract
Staphylococcus aureus (S. aureus) is a pathogen associated with a wide variety of diseases, from minor to life-threatening infections. Antibiotic-resistant strains have emerged, leading to increasing concern about the control of S. aureus infections. The development of vaccines may be one way to overcome these resistant strains. However, S. aureus ability to internalize into cells - and thus to form a reservoir escaping humoral immunity - is a challenge for vaccine development. A role of T cells in the elimination of persistent S. aureus has been established in mice but it remains to be established if CD8+ T cells could display a cytotoxic activity against S. aureus infected cells. We examined in vitro the ability of CD8+ T cells to recognize and kill dendritic cells infected with S. aureus. We first evidenced that both primary mouse dendritic cells and DC2.4 cell line can be infected with S. aureus. We then generated a strain of S. aureus expressing a model CD8 epitope and transgenic F5 CD8+ T cells recognizing this model epitope were used as reporter T cells. In response to S. aureus-infected dendritic cells, F5 CD8+ T cells produced IFN-γ in an antigen-specific manner and displayed an increased ability to kill infected cells. Altogether, these results demonstrate that cells infected by S. aureus display bacteria-derived epitopes at their surface that are recognized by CD8+ T cells. This paves the way for the development of CD8+ T cell-based therapies against S. aureus.
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Polaske TJ, West KHJ, Zhao K, Widner DL, York JT, Blackwell HE. Chemical and biomolecular insights into the Staphylococcus aureus agr quorum sensing system: Current progress and ongoing challenges. Isr J Chem 2023; 63:e202200096. [PMID: 38765792 PMCID: PMC11101167 DOI: 10.1002/ijch.202200096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Indexed: 03/19/2023]
Abstract
Staphylococcus aureus is a ubiquitous bacterium that has become a major threat to human health due to its extensive toxin production and tremendous capacity for antibiotic resistance (e.g., MRSA "superbug" infections). Amid a worsening antibiotic resistance crisis, new strategies to combat this deadly microbe that remove the selective pressure of traditional approaches are in high demand. S. aureus utilizes an accessory gene regulator (agr) quorum sensing network to monitor its local cellular population and trigger a devastating communal attack, like an invading horde, once a threshold cell density has been reached. The role of the agr system in a range of disease types is still being unraveled. Herein, we discuss the present-day biochemical understanding of agr along with unresolved details, describe its connection to the progression of infection, and review how chemical strategies have been implemented to study and intercept this signaling pathway. This research is illuminating the potential of agr as an anti-virulence target in S. aureus and should inform the study of similar, yet less studied, agr systems in related bacterial pathogens.
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Affiliation(s)
- Thomas J. Polaske
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Korbin H. J. West
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Ke Zhao
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Danielle L. Widner
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Jordan T. York
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Ave., Madison, WI 53706 USA
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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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