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Seebach E, Kubatzky KF. Chronic Implant-Related Bone Infections-Can Immune Modulation be a Therapeutic Strategy? Front Immunol 2019; 10:1724. [PMID: 31396229 PMCID: PMC6664079 DOI: 10.3389/fimmu.2019.01724] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 07/09/2019] [Indexed: 12/14/2022] Open
Abstract
Chronic implant-related bone infections are a major problem in orthopedic and trauma-related surgery with severe consequences for the affected patients. As antibiotic resistance increases in general and because most antibiotics have poor effectiveness against biofilm-embedded bacteria in particular, there is a need for alternative and innovative treatment approaches. Recently, the immune system has moved into focus as the key player in infection defense and bone homeostasis, and the targeted modulation of the host response is becoming an emerging field of interest. The aim of this review was to summarize the current knowledge of impaired endogenous defense mechanisms that are unable to prevent chronicity of bone infections associated with a prosthetic or osteosynthetic device. The presence of foreign material adversely affects the immune system by generating a local immune-compromised environment where spontaneous clearance of planktonic bacteria does not take place. Furthermore, the surface structure of the implant facilitates the transition of bacteria from the planktonic to the biofilm stage. Biofilm formation on the implant surface is closely linked to the development of a chronic infection, and a misled adaption of the immune system makes it impossible to effectively eliminate biofilm infections. The interaction between the immune system and bone cells, especially osteoclasts, is extensively studied in the field of osteoimmunology and this crosstalk further aggravates the course of bone infection by shifting bone homeostasis in favor of bone resorption. T cells play a major role in various chronic diseases and in this review a special focus was therefore set on what is known about an ineffective T cell response. Myeloid-derived suppressor cells (MDSCs), anti-inflammatory macrophages, regulatory T cells (Tregs) as well as osteoclasts all suppress immune defense mechanisms and negatively regulate T cell-mediated immunity. Thus, these cells are considered to be potential targets for immune therapy. The success of immune checkpoint inhibition in cancer treatment encourages the transfer of such immunological approaches into treatment strategies of other chronic diseases. Here, we discuss whether immune modulation can be a therapeutic tool for the treatment of chronic implant-related bone infections.
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Affiliation(s)
- Elisabeth Seebach
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University Hospital, Heidelberg, Germany
| | - Katharina F Kubatzky
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University Hospital, Heidelberg, Germany
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Hu C, Ashok D, Nisbet DR, Gautam V. Bioinspired surface modification of orthopedic implants for bone tissue engineering. Biomaterials 2019; 219:119366. [PMID: 31374482 DOI: 10.1016/j.biomaterials.2019.119366] [Citation(s) in RCA: 124] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 06/27/2019] [Accepted: 07/14/2019] [Indexed: 12/25/2022]
Abstract
Biomedical implants have been widely used in various orthopedic treatments, including total hip arthroplasty, joint arthrodesis, fracture fixation, non-union, dental repair, etc. The modern research and development of orthopedic implants have gradually shifted from traditional mechanical support to a bioactive graft in order to endow them with better osteoinduction and osteoconduction. Inspired by structural and mechanical properties of natural bone, this review provides a panorama of current biological surface modifications for facilitating the interaction between medical implants and bone tissue and gives a future outlook for fabricating the next-generation multifunctional and smart implants by systematically biomimicking the physiological processes involved in formation and functioning of bones.
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Affiliation(s)
- Chao Hu
- Research School of Engineering, Australian National University, ACT, 2601, Australia
| | - Deepu Ashok
- Research School of Engineering, Australian National University, ACT, 2601, Australia
| | - David R Nisbet
- Research School of Engineering, Australian National University, ACT, 2601, Australia
| | - Vini Gautam
- John Curtin School of Medical Research, Australian National University, ACT, 2601, Australia.
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53
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Ni S, Li B, Xu Y, Mao F, Li X, Lan L, Zhu J, Li J. Targeting virulence factors as an antimicrobial approach: Pigment inhibitors. Med Res Rev 2019; 40:293-338. [PMID: 31267561 DOI: 10.1002/med.21621] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/30/2019] [Accepted: 06/13/2019] [Indexed: 12/19/2022]
Abstract
The fascinating and dangerous colored pathogens contain unique chemically pigmented molecules, which give varied and efficient assistance as virulence factors to the crucial reproduction and growth of microbes. Therefore, multiple novel strategies and inhibitors have been developed in recent years that target virulence factor pigments. However, despite the importance and significance of this topic, it has not yet been comprehensively reviewed. Moreover, research groups around the world have made successful progress against antibacterial infections by targeting pigment production, including our serial works on the discovery of CrtN inhibitors against staphyloxanthin production in Staphylococcus aureus. On the basis of the previous achievements and recent progress of our group in this field, this article will be the first comprehensive review of pigment inhibitors against colored pathogens, especially S. aureus infections, and this article includes design strategies, representative case studies, advantages, limitations, and perspectives to guide future research.
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Affiliation(s)
- Shuaishuai Ni
- Cancer Institute, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Baoli Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Yixiang Xu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Fei Mao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Xiaokang Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Lefu Lan
- State Key Laboratory of Drug Research, Shanghai Institute of Material Medical, Chinese Academy of Sciences, Shanghai, China
| | - Jin Zhu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Jian Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China.,Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
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54
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Saeed K, McLaren AC, Schwarz EM, Antoci V, Arnold WV, Chen AF, Clauss M, Esteban J, Gant V, Hendershot E, Hickok N, Higuera CA, Coraça-Huber DC, Choe H, Jennings JA, Joshi M, Li WT, Noble PC, Phillips KS, Pottinger PS, Restrepo C, Rohde H, Schaer TP, Shen H, Smeltzer M, Stoodley P, Webb JCJ, Witsø E. 2018 international consensus meeting on musculoskeletal infection: Summary from the biofilm workgroup and consensus on biofilm related musculoskeletal infections. J Orthop Res 2019; 37:1007-1017. [PMID: 30667567 DOI: 10.1002/jor.24229] [Citation(s) in RCA: 101] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/14/2019] [Indexed: 02/04/2023]
Abstract
Biofilm-associated implant-related bone and joint infections are clinically important due to the extensive morbidity, cost of care and socioeconomic burden that they cause. Research in the field of biofilms has expanded in the past two decades, however, there is still an immense knowledge gap related to many clinical challenges of these biofilm-associated infections. This subject was assigned to the Biofilm Workgroup during the second International Consensus Meeting on Musculoskeletal Infection held in Philadelphia USA (ICM 2018) (https://icmphilly.com). The main objective of the Biofilm Workgroup was to prepare a consensus document based on a review of the literature, prepared responses, discussion, and vote on thirteen biofilm related questions. The Workgroup commenced discussing and refining responses prepared before the meeting on day one using Delphi methodology, followed by a tally of responses using an anonymized voting system on the second day of ICM 2018. The Working group derived consensus on information about biofilms deemed relevant to clinical practice, pertaining to: (1) surface modifications to prevent/inhibit biofilm formation; (2) therapies to prevent and treat biofilm infections; (3) polymicrobial biofilms; (4) diagnostics to detect active and dormant biofilm in patients; (5) methods to establish minimal biofilm eradication concentration for biofilm bacteria; and (6) novel anti-infectives that are effective against biofilm bacteria. It was also noted that biomedical research funding agencies and the pharmaceutical industry should recognize these areas as priorities. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.
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Affiliation(s)
- Kordo Saeed
- Department of Microbiology Hampshire Hospitals NHS Foundation Trust, Winchester and Basingstoke, UK and University of Southampton, School of Medicine, Southampton, UK
| | - Alex C McLaren
- Department of Orthopaedic Surgery, University of Arizona, College of Medicine-Phoenix, Phoenix, Arizona
| | - Edward M Schwarz
- Department of Orthopaedics, University of Rochester, Rochester, New York
| | - Valentin Antoci
- Department of Orthopaedics, University Orthopedics Rhode Island, Providence, Rhode Island
| | - William V Arnold
- Department of Orthopaedics, Rothman Institute at Thomas Jefferson University Hospital, Philadelphia, Pennsylvania
| | - Antonia F Chen
- Department of Orthopaedics, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Martin Clauss
- Department for Orthopaedics and Trauma Surgery Kantonsspital Baselland, Liestal and University Hospital Basel Department for Orthopaedics and Trauma Surgery, Basel, CH
| | - Jaime Esteban
- Department of Clinical Microbiology, IIS-Fundacion Jimenez Diaz, UAM, Av. Reyes Catolicos 2., 28040-Madrid, Spain
| | - Vanya Gant
- College Hospital, Hospital for Tropical Diseases, National Hospital for Neurology and Neurosurgery at University College London Hospitals, London, UK
| | - Edward Hendershot
- Department of Internal Medicine and Infectious Diseases at Duke University Hospital, Durham, North Carolina
| | - Noreen Hickok
- Department of Orthopaedic Surgery, Department of Biochemistry & Molecular Biology Thomas Jefferson University, 1015 Walnut St., Philadelphia, 19107, Pennsylvania
| | - Carlos A Higuera
- Levitetz Department of Orthopaedic Surgery, Cleveland Clinic Florida, Weston, Florida
| | - Débora C Coraça-Huber
- Research Laboratory for Implant Associated Infections (Biofilm Lab) - Experimental Orthopaedics, Department of Orthopaedic Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Hyonmin Choe
- Yokohama City University Orthopaedic Department, Fukuura-3-9, Kanazawa-ku, Yokohama, Japan
| | - Jessica A Jennings
- Department of Biomedical Engineering, The University of Memphis, 303B Engineering Technology Building, Memphis, Tennessee
| | - Manjari Joshi
- Department of Internal Medicine and Infectious Diseases at University of Mryland, School of Medicine, R Adams Cowley Shock Trauma Center Baltimore, Baltimore, Maryland
| | - William T Li
- Sydney Kimmel Medical College at Philadelphia University and Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Philip C Noble
- Institute of Orthopaedic Research and Education, Houston, Texas.,Baylor College of Medicine Department of Orthopaedic Surgery, Houston, Texas
| | - K Scott Phillips
- Division of Biology, Chemistry, and Materials Science, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, Office of Medical Products and Tobacco, US Food and Drug Administration, Silver Spring, Maryland
| | - Paul S Pottinger
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington
| | - Camilo Restrepo
- Department of Orthopaedics, Rothman Institute at Thomas Jefferson University Hospital, Philadelphia, Pennsylvania
| | - Holger Rohde
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Thomas P Schaer
- Department of Clinical Studies New Bolton Center, University of Pennsylvania School of Veterinary Medicine, Kennett Square, Pennsylvania
| | - Hao Shen
- Department of Orthopaedics, Shanghai Jiao Tong University Affiliated Sixth People' s Hospital, Shanghai, P. R. China
| | - Mark Smeltzer
- Department of Microbiology and Immunology, Department of Orthopaedic Surgery, Center for Microbial Pathogenesis and Host Inflammatory Responses, University of Arkansas for Medical Sciences 4301 W. Markham, Slot 511, Little Rock, 72205, Arkansas
| | - Paul Stoodley
- Department Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, Ohio.,Department Orthopaedics, College of Medicine, The Ohio State University, Columbus, Ohio.,Department National Centre for Advanced Tribology at Southampton (nCATS), Mechanical Engineering, University of Southampton, Southampton, UK
| | - Jason C J Webb
- Department of Orthopaedic Surgery, Avon Orthopaedic Centre, Southmead Hospital, Bristol, UK
| | - Eivind Witsø
- Department of Orthopaedic Surgery at St. Olavs Hospital, Trondheim, Norway
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55
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Aldrich A, Kuss MA, Duan B, Kielian T. 3D Bioprinted Scaffolds Containing Viable Macrophages and Antibiotics Promote Clearance of Staphylococcus aureus Craniotomy-Associated Biofilm Infection. ACS APPLIED MATERIALS & INTERFACES 2019; 11:12298-12307. [PMID: 30855125 PMCID: PMC7034353 DOI: 10.1021/acsami.9b00264] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Craniotomy involves the removal of a skull fragment to access the brain, such as during tumor or epilepsy surgery, which is immediately replaced intraoperatively. The infection incidence after craniotomy ranges from 0.8 to 3%, with approximately half caused by Staphylococcus aureus ( S. aureus). To mitigate infectious complications following craniotomy, we engineered a three-dimensional (3D) bioprinted bone scaffold to harness the potent antibacterial activity of macrophages (MΦs) together with antibiotics using a mouse S. aureus craniotomy-associated biofilm model that establishes a persistent infection on the bone flap, subcutaneous galea, and brain. The 3D scaffold contained rifampin and daptomycin printed in a composite slurry, with viable MΦs incorporated into a hydrogel-based bioink, which was assessed for both the treatment and prevention of craniotomy-associated infections in the mouse model. For the treatment paradigm, the bone flap was removed at day 7 post infection after a mature biofilm had formed and was replaced with a 3D printed antibiotic scaffold, with or without MΦ incorporation. Bacterial burdens in the galea and brain were reduced by at least 100-fold at early time points, which was potentiated by bioprinting viable MΦs into the 3D antibiotic scaffold. We also examined a prevention paradigm, where the scaffolds were placed at the time of surgery and challenged with S. aureus one day later at the surgical site. Interestingly, unlike the treatment paradigm, the incorporation of viable MΦs into the 3D antibiotic scaffold did not enhance bacterial clearance compared to that of antibiotic alone. With further refinement, our 3D bioprinted scaffold represents a potential treatment modality, as it delivers therapeutic antibiotic levels more rapidly than systemic administration, based on its proximity to the infection site. In addition, the incorporation of viable MΦs into the 3D scaffold is an important advance, which demonstrated an improved therapeutic benefit for the treatment of established biofilms that represent the most clinically challenging scenario.
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Affiliation(s)
- Amy Aldrich
- Department of Pathology and Microbiology University of Nebraska Medical Center, Omaha, NE 68198
| | - Mitchell A. Kuss
- Mary & Dick Holland Regenerative Medicine Program and Division of Cardiology, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198
| | - Bin Duan
- Mary & Dick Holland Regenerative Medicine Program and Division of Cardiology, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198
| | - Tammy Kielian
- Department of Pathology and Microbiology University of Nebraska Medical Center, Omaha, NE 68198
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56
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Staphylococcus aureus Biofilm-Conditioned Medium Impairs Macrophage-Mediated Antibiofilm Immune Response by Upregulating KLF2 Expression. Infect Immun 2019; 87:IAI.00643-18. [PMID: 30692179 DOI: 10.1128/iai.00643-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 01/20/2019] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus infections associated with the formation of biofilms on medical implants or host tissue play a critical role in the persistence of chronic infections. One critical mechanism of biofilm infection that leads to persistent infection lies in the capacity of biofilms to evade the macrophage-mediated innate immune response. It is now increasingly apparent that microorganisms exploit the negative regulatory mechanisms of the pattern recognition receptor (PRR)-mediated inflammatory response to subvert host cell functions by using various virulence factors. However, the detailed molecular mechanism, along with the identity of a target molecule, underlying the evasion of the macrophage-mediated innate immune response against S. aureus infection associated with biofilm formation remains to be elucidated. Here, using an in vitro culture model of murine macrophage-like RAW 264.7 cells, we demonstrate that S. aureus biofilm-conditioned medium significantly attenuated the capacity for macrophage bactericidal and proinflammatory responses. Importantly, the responses were associated with attenuated activation of NF-κB and increased expression of Kruppel-like factor 2 (KLF2) in RAW 264.7 cells. Small interfering RNA (siRNA)-mediated silencing of KLF2 in RAW 264.7 cells could restore the activation of NF-κB toward the bactericidal activity and generation of proinflammatory cytokines in the presence of S. aureus biofilm-conditioned medium. Collectively, our results suggest that factors secreted from S. aureus biofilms might exploit the KLF2-dependent negative regulatory mechanism to subvert macrophage-mediated innate immune defense against S. aureus biofilms.
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57
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Martínez-Colón GJ, Warheit-Niemi H, Gurczynski SJ, Taylor QM, Wilke CA, Podsiad AB, Crespo J, Bhan U, Moore BB. Influenza-induced immune suppression to methicillin-resistant Staphylococcus aureus is mediated by TLR9. PLoS Pathog 2019; 15:e1007560. [PMID: 30682165 PMCID: PMC6364947 DOI: 10.1371/journal.ppat.1007560] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 02/06/2019] [Accepted: 01/03/2019] [Indexed: 12/15/2022] Open
Abstract
Bacterial lung infections, particularly with methicillin-resistant Staphylococcus aureus (MRSA), increase mortality following influenza infection, but the mechanisms remain unclear. Here we show that expression of TLR9, a microbial DNA sensor, is increased in murine lung macrophages, dendritic cells, CD8+ T cells and epithelial cells post-influenza infection. TLR9-/- mice did not show differences in handling influenza nor MRSA infection alone. However, TLR9-/- mice have improved survival and bacterial clearance in the lung post-influenza and MRSA dual infection, with no difference in viral load during dual infection. We demonstrate that TLR9 is upregulated on macrophages even when they are not themselves infected, suggesting that TLR9 upregulation is related to soluble mediators. We rule out a role for elevations in interferon-γ (IFNγ) in mediating the beneficial MRSA clearance in TLR9-/- mice. While macrophages from WT and TLR9-/- mice show similar phagocytosis and bacterial killing to MRSA alone, following influenza infection, there is a marked upregulation of scavenger receptor A and MRSA phagocytosis as well as inducible nitric oxide synthase (Inos) and improved bacterial killing that is specific to TLR9-deficient cells. Bone marrow transplant chimera experiments and in vitro experiments using TLR9 antagonists suggest TLR9 expression on non-hematopoietic cells, rather than the macrophages themselves, is important for regulating myeloid cell function. Interestingly, improved bacterial clearance post-dual infection was restricted to MRSA, as there was no difference in the clearance of Streptococcus pneumoniae. Taken together these data show a surprising inhibitory role for TLR9 signaling in mediating clearance of MRSA that manifests following influenza infection. Influenza-associated secondary bacterial infections, particularly with methicillin-resistant Staphylococcus aureus (MRSA), are a major cause of morbidity and mortality, and better therapeutic strategies are needed. Stimulation of TLR2 has shown promise for improving health in influenza-bacteria dual-infected animals. However, nothing is known about the role of other TLRs, including TLR9, in influenza-bacteria dual infection pathology. This is the first study of TLR9 regulation of influenza-bacterial superinfection and it highlights an unexpected pathologic role for TLR9 in regulating clearance of MRSA post-H1N1. It also highlights the important observation that TLR9 signaling has very different outcomes in the setting of influenza infection than in naïve mice and shows important distinctions in the mechanisms for susceptibility to MRSA vs. S. pneumoniae post-influenza. Our results also suggest that TLR9 expression on non-hematopoietic cells regulates macrophage function in vivo.
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Affiliation(s)
| | - Helen Warheit-Niemi
- Microbiology and Immunology Graduate Program, University of Michigan, Ann Arbor, MI United States of America
| | - Stephen J. Gurczynski
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States of America
| | - Quincy M. Taylor
- Literature, Sciences and the Arts, Microbiology, University of Michigan, Ann Arbor, MI, United States of America
| | - Carol A. Wilke
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States of America
| | - Amy B. Podsiad
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States of America
| | - Joel Crespo
- Graduate Program in Immunology, University of Michigan, Ann Arbor, MI, United States of America
| | - Urvashi Bhan
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States of America
| | - Bethany B. Moore
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States of America
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, United States of America
- * E-mail:
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58
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Peng KT, Chiang YC, Huang TY, Chen PC, Chang PJ, Lee CW. Curcumin nanoparticles are a promising anti-bacterial and anti-inflammatory agent for treating periprosthetic joint infections. Int J Nanomedicine 2019; 14:469-481. [PMID: 30666108 PMCID: PMC6333393 DOI: 10.2147/ijn.s191504] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background Periprosthetic joint infections (PJIs) have a high incidence of recurrence after total joint replacement and are difficult to treat by debridement or antibiotic treatment. Curcumin is a natural product with anti-inflammatory and anti-bacterial properties. The low bioactivity of curcumin in water restricts its clinical application. Curcumin nanoparticles (CURN) were developed to overcome this limitation. Methods In this study, the therapeutic effects of CURN and their anti-inflammatory functions were investigated in a Staphylococcus aureus biofilm-induced PJIs model. Results CURN first attenuated the biofilm-induced expansion of myeloid-derived suppressor cells (MDSCs) and then regulated M1- and M2-phenotypic MDSC expression. Down-regulation of cytokines and reactive oxygen species was considered as the mechanism of CURN in reversing the suppression of T cell proliferation. The recovery of bone permeative destruction demonstrated that CURN enhanced therapeutic potency of vancomycin in vivo. Conclusion This is the first study to demonstrate that CURN may be useful for treating PJIs.
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Affiliation(s)
- Kuo-Ti Peng
- Department of Orthopaedic Surgery, Chang Gung Memorial Hospital, Puzi City, Chiayi County 61363, Taiwan, .,College of Medicine, Chang Gung University, Guishan District, Taoyuan City 33303, Taiwan,
| | - Yao-Chang Chiang
- Department of Nursing, Chang Gung University of Science and Technology, Puzi City, Chiayi County 61363, Taiwan, .,Division of Basic Medical Sciences, and Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Puzi City, Chiayi County 61363, Taiwan,
| | - Tsung-Yu Huang
- Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan.,Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
| | - Pei-Chun Chen
- Department of Orthopaedic Surgery, Chang Gung Memorial Hospital, Puzi City, Chiayi County 61363, Taiwan,
| | - Pey-Jium Chang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang-Gung University, Taoyuan, Taiwan.,Department of Nephrology, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Chiang-Wen Lee
- Department of Nursing, Chang Gung University of Science and Technology, Puzi City, Chiayi County 61363, Taiwan, .,Division of Basic Medical Sciences, and Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Puzi City, Chiayi County 61363, Taiwan, .,Research Center for Industry of Human Ecology and Research Center for Chinese Herbal Medicine, Chang Gung University of Science and Technology, Guishan District, Taoyuan City 33303, Taiwan, .,Department of Rehabilitation, Chang Gung Memorial Hospital, Puzi City, Chiayi County 61363, Taiwan,
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59
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Shiels SM, Tennent DJ, Lofgren AL, Wenke JC. Topical rifampin powder for orthopaedic trauma part II: Topical rifampin allows for spontaneous bone healing in sterile and contaminated wounds. J Orthop Res 2018; 36:3142-3150. [PMID: 30270538 DOI: 10.1002/jor.24155] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 09/24/2018] [Indexed: 02/04/2023]
Abstract
Infectious complications can reduce fracture healing rate. Broad spectrum antibiotics are commonly administered to prevent and treat musculoskeletal infections. Local antibiotics are applied to the wound site to increase therapeutic concentrations without increasing systemic toxicity, however, may hinder local tissue recovery. Rifampin has been shown to eradicate mature Staphylococcal biofilms and its use proven for treating musculoskeletal infections. In this study, a spontaneously healing defect model in a rat was used to investigate the impact rifampin powder has on endogenous bone healing in both a sterile and contaminated wound. No significant differences were identified in bone volume fraction via microcomputed tomography, radiological scoring, or histology between an empty defect and animals that received vancomycin or rifampin powder in a sterile wound. When applied to a contaminated musculoskeletal wound, the rifampin powder had significantly greater bone formation compared to the control, as measured by microcomputed tomography, plain radiology, and histology. In addition, the animals treated with rifampin powder had reduced bacteria, reduced white blood cell count and reduced number of clinical indications of infection. Interestingly, while the vancomycin group still displayed signs of infection via quantitative microbiology, plain radiology, and histology, there was significant bone formation within the defect and reduction of systemic signs of infection. We demonstrated that the use of rifampin powder allows bone to heal in both a sterile and contaminated model of musculoskeletal infection. To our knowledge, this is the first time the direct impact of local antibiotics on bone healing has been investigated. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. J Orthop Res 36:3142-3150, 2018.
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Affiliation(s)
- Stefanie M Shiels
- U.S. Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, Texas, 78234
| | - David J Tennent
- US Army Institute of Surgical Research, Fort Sam Houston, Department of Orthopaedics, Brooke Army Medical Center, Fort Sam Houston, Texas
| | - Alicia L Lofgren
- U.S. Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, Texas, 78234
| | - Joseph C Wenke
- U.S. Army Institute of Surgical Research, 3698 Chambers Pass, Fort Sam Houston, Texas, 78234
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60
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Heterogeneity of Ly6G + Ly6C + Myeloid-Derived Suppressor Cell Infiltrates during Staphylococcus aureus Biofilm Infection. Infect Immun 2018; 86:IAI.00684-18. [PMID: 30249747 DOI: 10.1128/iai.00684-18] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 09/20/2018] [Indexed: 01/11/2023] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature monocytes and granulocytes. While neutrophils (polymorphonuclear leukocytes [PMNs]) are classically identified as highly differentiated cells specialized for antimicrobial defense, our laboratory has reported minor contributions of PMNs to the immune response during Staphylococcus aureus biofilm infection. However, these two cell types can be difficult to differentiate because of shared surface marker expression. Here we describe a more refined approach to distinguish MDSCs from PMNs utilizing the integrin receptor CD11b combined with conventional Ly6G and Ly6C expression. This approach separated the Ly6G+ Ly6C+ population that we previously identified in a mouse model of S. aureus orthopedic implant infection into two subsets, namely, CD11bhigh Ly6G+ Ly6C+ MDSCs and CD11blow Ly6G+ Ly6C+ PMNs, which was confirmed by characteristic nuclear morphology using cytospins. CD11bhigh Ly6G+ Ly6C+ MDSCs suppressed T cell proliferation throughout the 28-day infection period, whereas CD11blow Ly6G+ Ly6C+ PMNs had no effect early (day 3 postinfection), although this population acquired suppressive activity at later stages of biofilm development. To further highlight the distinctions between biofilm-associated MDSCs and PMNs versus monocytes, transcriptional profiles were compared by transcriptome sequencing (RNA-Seq). A total of 6,466 genes were significantly differentially expressed in MDSCs versus monocytes, whereas only 297 genes were significantly different between MDSCs and PMNs. A number of genes implicated in cell cycle regulation were identified, and in vivo ethynyldeoxyuridine (EdU) labeling revealed that approximately 50% of MDSCs proliferated locally at the site of S. aureus biofilm infection. Based on their similar transcriptomic profiles to those of PMNs, biofilm-associated MDSCs are of a granulocytic lineage and can be classified as granulocytic MDSCs (G-MDSCs).
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61
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Yamada KJ, Kielian T. Biofilm-Leukocyte Cross-Talk: Impact on Immune Polarization and Immunometabolism. J Innate Immun 2018; 11:280-288. [PMID: 30347401 DOI: 10.1159/000492680] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 07/30/2018] [Indexed: 12/17/2022] Open
Abstract
Biofilms are bacterial communities contained within an extracellular matrix, which can colonize both native tissues and artificial surfaces. In particular, indwelling medical devices and prosthetic implants are targets for biofilm formation because they facilitate bacterial attachment via host proteins that coat the foreign body. Biofilm infections are particularly challenging to treat, since they are not readily cleared by antibiotics, require invasive procedures to eradicate, and are prone to recurrence. It has been demonstrated that biofilm-derived products can actively suppress proinflammatory immune responses, as evident by the recruitment of myeloid-derived suppressor cells and macrophage (MФ) polarization towards an anti-inflammatory state. Recent studies have shown that alterations in leukocyte metabolism shape their inflammatory phenotype and function. For example, anti-inflammatory MФs are biased towards oxidative phosphorylation whereas proinflammatory MФs favor aerobic glycolysis. This review will compare the immune responses elicited by planktonic and biofilm bacterial infections, with a discussion on the metabolic properties of MФs and neutrophils in response to both bacterial growth conditions.
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Affiliation(s)
- Kelsey J Yamada
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, USA,
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Protective immunity in recurrent Staphylococcus aureus infection reflects localized immune signatures and macrophage-conferred memory. Proc Natl Acad Sci U S A 2018; 115:E11111-E11119. [PMID: 30297395 DOI: 10.1073/pnas.1808353115] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Staphylococcus aureus is the leading cause of skin and skin structure infection (SSSI), a primary portal of entry for invasive infection. Our prior studies discovered a role for protective innate memory against recurrent methicillin-resistant S. aureus (MRSA) SSSI. In the present study, the dynamics and mechanisms of this response were explored in recurrent SSSI in WT mice. Priming by prior infection reduced skin lesion severity and MRSA burden, and protected against dissemination at day 7 but not day 2. Cytokine and cellular signatures in SSSI differed at day 2 versus 7, and were distinct in skin versus blood or spleen. Cytokines associated with protection in skin included increased IL-17, IL-6, monokine inducible by IFN-γ (MIG), and RANTES, while increased IP-10 correlated with protection from dissemination. Cellular signatures of protection included increased Th17, M1 macrophage, and dendritic cell populations in abscesses, and total macrophages in lymph nodes. Priming potentiated S. aureus-specific phagocytic killing by bone marrow-derived macrophages in vitro, and their adoptive transfer into naïve skin afforded protective efficacy in vivo. Present findings indicate that protective immunity in recurrent S. aureus infection is locally targeted, and involves specific memory conferred by macrophages. These insights provide targets for vaccine and immunotherapeutic development against MRSA.
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63
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Arginase-1 Expression in Myeloid Cells Regulates Staphylococcus aureus Planktonic but Not Biofilm Infection. Infect Immun 2018; 86:IAI.00206-18. [PMID: 29661929 DOI: 10.1128/iai.00206-18] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 04/09/2018] [Indexed: 02/07/2023] Open
Abstract
Staphylococcus aureus is a leading cause of device-associated biofilm infections, which represent a serious health care concern based on their chronicity and antibiotic resistance. We previously reported that S. aureus biofilms preferentially recruit myeloid-derived suppressor cells (MDSCs), which promote monocyte and macrophage anti-inflammatory properties. This is associated with increased myeloid arginase-1 (Arg-1) expression, which has been linked to anti-inflammatory and profibrotic activities that are observed during S. aureus biofilm infections. To determine whether MDSCs and macrophages utilize Arg-1 to promote biofilm infection, Arg-1 was deleted in myeloid cells by use of Tie-2Cre mice. Despite Arg-1 expression in biofilm-associated myeloid cells, bacterial burdens and leukocyte infiltrates were similar between wild-type (WT) and Arg-1fl/fl;Tie-2Cre conditional knockout (KO) mice from days 3 to 14 postinfection in both orthopedic implant and catheter-associated biofilm models. However, inducible nitric oxide synthase (iNOS) expression was dramatically elevated in biofilm-associated MDSCs from Arg-1fl/fl;Tie-2Cre animals, suggesting a potential Arg-1-independent compensatory mechanism for MDSC-mediated immunomodulation. Treatment of Arg-1fl/fl;Tie-2Cre mice with the iNOS inhibitor N6-(1-iminoethyl)-l-lysine (l-NIL) had no effect on biofilm burdens or immune infiltrates, whereas treatment of WT mice with the Arg-1/ornithine decarboxylase inhibitor difluoromethylornithine (DFMO) increased bacterial titers, but only in the surrounding soft tissues, which possess attributes of a planktonic environment. A role for myeloid-derived Arg-1 in regulating planktonic infection was confirmed using a subcutaneous abscess model, in which S. aureus burdens were significantly increased in Arg-1fl/fl;Tie-2Cre mice compared to those in WT mice. Collectively, these results indicate that the effects of myeloid Arg-1 are context dependent and are manifest during planktonic but not biofilm infection.
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Heim CE, Vidlak D, Odvody J, Hartman CW, Garvin KL, Kielian T. Human prosthetic joint infections are associated with myeloid-derived suppressor cells (MDSCs): Implications for infection persistence. J Orthop Res 2018; 36:1605-1613. [PMID: 29139571 PMCID: PMC5953848 DOI: 10.1002/jor.23806] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/11/2017] [Indexed: 02/04/2023]
Abstract
UNLABELLED Prosthetic joint infection (PJI) is a devastating complication of joint arthroplasty surgery typified by biofilm formation. Currently, mechanisms whereby biofilms persist and evade immune-mediated clearance in immune competent patients remain largely ill-defined. Therefore, the current study characterized leukocyte infiltrates and inflammatory mediator expression in tissues from patients with PJI compared to aseptic loosening. CD33+ HLA-DR- CD66b+ CD14-/low granulocytic myeloid-derived suppressor cells (G-MDSCs) were the predominant leukocyte population at sites of human PJI compared to aseptic tissues. MDSCs inhibit T cell proliferation, which coincided with reduced T cells in PJIs compared to aseptic tissues. IL-10, IL-6, and CXCL1 were significantly elevated in PJI tissues and have been implicated in MDSC inhibitory activity, expansion, and recruitment, respectively, which may account for their preferential increase in PJIs. This bias towards G-MDSC accumulation during human PJI could account for the chronicity of these infections by preventing the pro-inflammatory, antimicrobial actions of immune effector cells. CLINICAL SIGNIFICANCE Animal models of PJI have revealed a critical role for MDSCs and IL-10 in promoting infection persistence; however, whether this population is prevalent during human PJI and across distinct bacterial pathogens remains unknown. This study has identified that granulocytic-MDSC infiltrates are unique to human PJIs caused by distinct bacteria, which are not associated with aseptic loosening of prosthetic joints. Better defining the immune status of human PJIs could lead to novel immune-mediated approaches to facilitate PJI clearance in combination with conventional antibiotics. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1605-1613, 2018.
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Affiliation(s)
- Cortney E. Heim
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Debbie Vidlak
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Jessica Odvody
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
| | - Curtis W. Hartman
- Department of Orthopaedic Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha, NE 68198
| | - Kevin L. Garvin
- Department of Orthopaedic Surgery and Rehabilitation, University of Nebraska Medical Center, Omaha, NE 68198
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198,Corresponding Author: Tammy Kielian, Ph.D., University of Nebraska Medical Center, Department of Pathology and Microbiology, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, Phone: (402) 559-8002, FAX: (402) 559-5900,
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65
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Ma P, Han H, Qin H. Reply to: "Studies of macrophage therapy for cirrhosis - From mice to men". J Hepatol 2018; 68:1091-1093. [PMID: 29317296 DOI: 10.1016/j.jhep.2017.12.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 12/29/2017] [Indexed: 12/04/2022]
Affiliation(s)
- Pengfei Ma
- State Key Laboratory of Cancer Biology, Department of Medical Genetics and Developmental Biology, Fourth Military Medical University, Xi'an, China; Department of Hepatobiliary Surgery, PLA Navy General Hospital, Beijing, China
| | - Hua Han
- State Key Laboratory of Cancer Biology, Department of Medical Genetics and Developmental Biology, Fourth Military Medical University, Xi'an, China
| | - Hongyan Qin
- State Key Laboratory of Cancer Biology, Department of Medical Genetics and Developmental Biology, Fourth Military Medical University, Xi'an, China.
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66
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González JF, Hahn MM, Gunn JS. Chronic biofilm-based infections: skewing of the immune response. Pathog Dis 2018; 76:4956043. [PMID: 29718176 PMCID: PMC6251518 DOI: 10.1093/femspd/fty023] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 03/13/2018] [Indexed: 12/20/2022] Open
Abstract
Many of the deadliest bacterial diseases that plague humanity in the modern age are caused by bacterial biofilms that produce chronic infections. However, most of our knowledge of the host immune response comes from the study of planktonic pathogens. While there are similarities in the host response to planktonic and biofilm bacteria, specific immune responses toward biofilms have not been well studied; the only apparent difference is the inability to clear the bacteria allowing the biofilm infection to become chronic. In some cases, the biofilms skew T-cell response toward a balance that allows a stalemate between the host and the pathogen, in which the infection can become persistent. In this minireview, we will summarize well-known examples of this phenomena as well as some emerging studies that may indicate that this situation is much more common than initially thought.
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Affiliation(s)
- Juan F González
- Department of Microbial Infection and Immunity, Infectious Diseases Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Mark M Hahn
- Department of Microbial Infection and Immunity, Infectious Diseases Institute, The Ohio State University, Columbus, OH 43210, USA
| | - John S Gunn
- Department of Microbial Infection and Immunity, Infectious Diseases Institute, The Ohio State University, Columbus, OH 43210, USA
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Abstract
The primary virulence factor of the skin commensal and opportunistic pathogen, Staphylococcus epidermidis, is the ability to form biofilms on surfaces of implanted materials. Much of this microorganism’s pathogenic success has been attributed to its ability to evade the innate immune system. The primary defense against S. epidermidis biofilm infection consists of complement activation, recruitment and subsequent killing of the pathogen by effector cells. Among pathogen-derived factors, the biofilm exopolysaccharide polysaccharide intercellular adhesion (PIA), as well as the accumulation-associated protein (Aap), and the extracellular matrix binding protein (Embp) have been shown to modulate effector cell-mediated killing of S. epidermidis. Phenol-soluble modulins (PSMs) constitute the only class of secreted toxins by S. epidermidis, at least one type of which (PSMδ) possesses strong cytolytic properties toward leukocytes. However, through selective production of non-cytolytic subtypes of PSMs, S. epidermidis is able to maintain a low inflammatory infection profile and avoid eradication by the host immune system. Taken together, our emerging understanding of the mechanisms behind immune modulation by S. epidermidis elucidates the microorganism’s success in the initial colonization of device surfaces as well as the maintenance of a chronic and indolent course of biofilm infection.
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Affiliation(s)
- Katherine Y Le
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States.,Division of Hospital Internal Medicine, Department of Medicine, Mayo Clinic College of Medicine and Science, Rochester, MN, United States
| | - Matthew D Park
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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68
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Forestier C, Billard E, Milon G, Gueirard P. Unveiling and Characterizing Early Bilateral Interactions between Biofilm and the Mouse Innate Immune System. Front Microbiol 2017; 8:2309. [PMID: 29209305 PMCID: PMC5702342 DOI: 10.3389/fmicb.2017.02309] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/08/2017] [Indexed: 12/20/2022] Open
Abstract
A very substantial progress has been made in our understanding of infectious diseases caused by invasive bacteria. Under their planktonic forms, bacteria transiently reside in the otherwise sterile mammal body tissues, as the physiological inflammation insures both their clearance and repair of any tissue damage. Yet, the bacteria prone to experience planktonic to biofilm developmental transition still need to be studied. Of note, sessile bacteria not only persist but also concur preventing the effectors and regulators of the physiological inflammation to operate. Thus, it is urgent to design biologically sound experimental approaches aimed to extract, at the earliest stage, immune signatures of mono-bacteria planktonic to biofilm developmental transition in vivo and ex vivo. Indeed, the transition is often the first event to which succeeds the “chronicization” process whereby classical bacteria-targeting therapies are no more efficacious. An in vivo model of micro-injection of Staphylococcus aureus planktonic or biofilm cells in the ear pinna dermis of laboratory transgenic mice with fluorescent immune cells is proposed. It allows visualizing, in real time, the range of the early interactions between the S. aureus and myeloid cell subsets- the resident macrophages and dendritic cells, the recruited neutrophil granulocytes/polymorphonuclear neutrophils, monocytes otherwise known to differentiate as macrophages or dendritic cells. One main objective is to extract contrasting immune signatures of the modulation of the physiological inflammation with respect to the two bacterial lifestyles.
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Affiliation(s)
- Christiane Forestier
- CNRS UMR 6023, Laboratoire Microorganismes: Génome et Environnement, Université Clermont-Auvergne, Clermont-Ferrand, France
| | - Elisabeth Billard
- INRA USC 2018, Inserm U1071, Laboratoire Microbes Intestin Inflammation et Susceptibilité de l'Hôte, Université Clermont-Auvergne, Clermont-Ferrand, France
| | | | - Pascale Gueirard
- CNRS UMR 6023, Laboratoire Microorganismes: Génome et Environnement, Université Clermont-Auvergne, Clermont-Ferrand, France
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69
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Peng KT, Hsieh CC, Huang TY, Chen PC, Shih HN, Lee MS, Chang PJ. Staphylococcus aureus biofilm elicits the expansion, activation and polarization of myeloid-derived suppressor cells in vivo and in vitro. PLoS One 2017; 12:e0183271. [PMID: 28813499 PMCID: PMC5559065 DOI: 10.1371/journal.pone.0183271] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 08/01/2017] [Indexed: 01/14/2023] Open
Abstract
Staphylococcus aureus (S. aureus) is one of the most common causes of biofilm infections in periprosthetic joint infections (PJIs). Accumulating evidence has shown that the immunosuppressive environment established by S. aureus biofilm infection in PJIs involves the presence of myeloid-derived suppressor cells (MDSCs) and M2-macrophages. Due to the diversity of MDSCs, little is known about whether S. aureus biofilm preferentially expands specific MDSC subsets or whether MDSCs can further differentiate into M2-macrophages during S. aureus biofilm infection. Here, we show that in agreement with the results from an established rat PJI model, S. aureus biofilm cocultured with freshly isolated bone marrow cells (BMCs) in vitro significantly increases the proportions of MDSCs, total macrophages and M2-macrophages. Interestingly, we find that treatment of the BMCs in vitro with S. aureus biofilm preferentially promotes the expansion of monocytic MDSCs but not granulocytic MDSCs. Biofilm treatment also substantially enhances the overall MDSC immunosuppressive activity in addition to the MDSC expansion in vitro. Importantly, we provide evidence that S. aureus biofilm is capable of further stimulating the conversion of monocytic MDSCs into M2-macrophages in vitro and in vivo. Collectively, our studies reveal a direct link between MDSCs and M2-macrophages occurring in S. aureus-associated PJIs.
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Affiliation(s)
- Kuo-Ti Peng
- Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | | | - Tsung-Yu Huang
- Division of Infection Disease, Department of Internal Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Pei-Chun Chen
- Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Hsin-Nung Shih
- Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Mel S. Lee
- Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Pey-Jium Chang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Department of Nephrology, Chang-Gung Memorial Hospital, Chiayi, Taiwan
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70
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Velsko IM, Cruz-Almeida Y, Huang H, Wallet SM, Shaddox LM. Cytokine response patterns to complex biofilms by mononuclear cells discriminate patient disease status and biofilm dysbiosis. J Oral Microbiol 2017; 9:1330645. [PMID: 28748035 PMCID: PMC5508357 DOI: 10.1080/20002297.2017.1330645] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Indexed: 01/30/2023] Open
Abstract
Localized aggressive periodontitis (LAP) is a rare form of periodontal disease with site-specific rapid tissue destruction. A lipopolysaccharide (LPS) hyper-inflammatory response was shown in LAP using peripheral whole blood, although responses to other bacterial surface components or complex oral biofilms have not been evaluated. Peripheral blood mononuclear cells (PBMCs) from 14 LAP patients, 15 healthy siblings (HS), and 13 unrelated healthy controls (HC) were stimulated with: LPS, lipoteichoic acid, or peptidoglycan; intact or sonically dispersed in vitro–grown biofilms from a LAP disease site, a LAP healthy site, or a healthy control site. Cell culture supernatants were assayed for 14 cyto/chemokines. Discriminant function analysis determined cyto/chemokines that discriminate disease status by response patterns to different stimuli. Qualitative differences in the cytokine response pattern among patient groups were observed to intact and dispersed biofilms, yet responses to healthy and diseased biofilms could not be discriminated. Despite an equivalent magnitude of response, LAP-derived PBMCs demonstrated a qualitatively different pattern of response to LPS and dispersed biofilms. PMBCs from each group responded distinctly to stimulation withsubgingival biofilms. Multiple underlying mechanisms related to bacterial-induced inflammatory responses can culminate in LAP disease initiation and/or progression, and biofilm homeostasis could play an important role.
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Affiliation(s)
- I M Velsko
- Department of Periodontology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - Y Cruz-Almeida
- Institute for Aging, College of Medicine, University of Florida, Gainesville, FL, USA
| | - H Huang
- Department of Periodontology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - S M Wallet
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - L M Shaddox
- Department of Periodontology, College of Dentistry, University of Florida, Gainesville, FL, USA.,Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
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71
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Fella E, Sokratous K, Papacharalambous R, Kyriacou K, Phillips J, Sanderson S, Panayiotou E, Kyriakides T. Pharmacological Stimulation of Phagocytosis Enhances Amyloid Plaque Clearance; Evidence from a Transgenic Mouse Model of ATTR Neuropathy. Front Mol Neurosci 2017; 10:138. [PMID: 28539873 PMCID: PMC5423984 DOI: 10.3389/fnmol.2017.00138] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 04/21/2017] [Indexed: 12/11/2022] Open
Abstract
Hereditary ATTR V30M amyloidosis is a lethal autosomal dominant sensorimotor and autonomic neuropathy caused by deposition of aberrant transthyretin (TTR). Immunohistochemical examination of sural nerve biopsies in patients with amyloidotic neuropathy show co-aggregation of TTR with several proteins; including apolipoprotein E, serum amyloid P and components of the complement cascade. Complement activation and macrophages are increasingly recognized to play a crucial role in amyloidogenesis at the tissue bed level. In the current study we test the effect of two C5a receptor agonists and a C5a receptor antagonist (PMX53) on disease phenotype in ATTR V30M mice. Our results indicate that amyloid deposition was significantly reduced following treatment with the C5a receptor agonists, while treatment with the antagonist resulted in a significant increase of amyloid load. Administration of the C5a receptor agonists triggered increased recruitment of phagocytic cells resulting in clearance of amyloid deposits.
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Affiliation(s)
- Eleni Fella
- Neurology Clinic A, The Cyprus Institute of Neurology and GeneticsNicosia, Cyprus.,Cyprus School of Molecular MedicineNicosia, Cyprus
| | - Kleitos Sokratous
- Electron Microscopy and Molecular Pathology Department, The Cyprus Institute of Neurology and GeneticsNicosia, Cyprus.,Bioinformatics Group, The Cyprus Institute of Neurology and GeneticsNicosia, Cyprus
| | | | - Kyriacos Kyriacou
- Cyprus School of Molecular MedicineNicosia, Cyprus.,Electron Microscopy and Molecular Pathology Department, The Cyprus Institute of Neurology and GeneticsNicosia, Cyprus
| | - Joy Phillips
- Donald P. Shiley Bioscience Center, San Diego State UniversitySan Diego, CA, USA
| | - Sam Sanderson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical CenterOmaha, NE, USA
| | - Elena Panayiotou
- Neurology Clinic A, The Cyprus Institute of Neurology and GeneticsNicosia, Cyprus
| | - Theodoros Kyriakides
- Neurology Clinic A, The Cyprus Institute of Neurology and GeneticsNicosia, Cyprus.,Cyprus School of Molecular MedicineNicosia, Cyprus
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Gries CM, Kielian T. Staphylococcal Biofilms and Immune Polarization During Prosthetic Joint Infection. J Am Acad Orthop Surg 2017; 25 Suppl 1:S20-S24. [PMID: 27922945 PMCID: PMC5640443 DOI: 10.5435/jaaos-d-16-00636] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Staphylococcal species are a leading cause of community- and nosocomial-acquired infections, where the placement of foreign materials increases infection risk. Indwelling medical devices and prosthetic implants are targets for staphylococcal cell adherence and biofilm formation. Biofilm products actively suppress proinflammatory microbicidal responses, as evident by macrophage polarization toward an anti-inflammatory phenotype and the recruitment of myeloid-derived suppressor cells. With the rise in prosthetic hip and knee arthroplasty procedures, together with the recalcitrance of biofilm infections to antibiotic therapy, it is imperative to better understand the mechanism of crosstalk between biofilm-associated bacteria and host immune cells. This review describes the current understanding of how staphylococcal biofilms evade immune-mediated clearance to establish persistent infections. The findings described herein may facilitate the identification of novel treatments for these devastating biofilm-mediated infections.
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Affiliation(s)
- Casey M. Gries
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
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Gogoi-Tiwari J, Williams V, Waryah CB, Costantino P, Al-Salami H, Mathavan S, Wells K, Tiwari HK, Hegde N, Isloor S, Al-Sallami H, Mukkur T. Mammary Gland Pathology Subsequent to Acute Infection with Strong versus Weak Biofilm Forming Staphylococcus aureus Bovine Mastitis Isolates: A Pilot Study Using Non-Invasive Mouse Mastitis Model. PLoS One 2017; 12:e0170668. [PMID: 28129375 PMCID: PMC5271311 DOI: 10.1371/journal.pone.0170668] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 01/09/2017] [Indexed: 12/30/2022] Open
Abstract
Background Biofilm formation by Staphylococcus aureus is an important virulence attribute because of its potential to induce persistent antibiotic resistance, retard phagocytosis and either attenuate or promote inflammation, depending upon the disease syndrome, in vivo. This study was undertaken to evaluate the potential significance of strength of biofilm formation by clinical bovine mastitis-associated S. aureus in mammary tissue damage by using a mouse mastitis model. Methods Two S. aureus strains of the same capsular phenotype with different biofilm forming strengths were used to non-invasively infect mammary glands of lactating mice. Biofilm forming potential of these strains were determined by tissue culture plate method, ica typing and virulence gene profile per detection by PCR. Delivery of the infectious dose of S. aureus was directly through the teat lactiferous duct without invasive scraping of the teat surface. Both bacteriological and histological methods were used for analysis of mammary gland pathology of mice post-infection. Results Histopathological analysis of the infected mammary glands revealed that mice inoculated with the strong biofilm forming S. aureus strain produced marked acute mastitic lesions, showing profuse infiltration predominantly with neutrophils, with evidence of necrosis in the affected mammary glands. In contrast, the damage was significantly less severe in mammary glands of mice infected with the weak biofilm-forming S. aureus strain. Although both IL-1β and TNF-α inflammatory biomarkers were produced in infected mice, level of TNF-α produced was significantly higher (p<0.05) in mice inoculated with strong biofilm forming S. aureus than the weak biofilm forming strain. Conclusion This finding suggests an important role of TNF-α in mammary gland pathology post-infection with strong biofilm-forming S. aureus in the acute mouse mastitis model, and offers an opportunity for the development of novel strategies for reduction of mammary tissue damage, with or without use of antimicrobials and/or anti-inflammatory compounds for the treatment of bovine mastitis.
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Affiliation(s)
- Jully Gogoi-Tiwari
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
- College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram, India
| | - Vincent Williams
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
| | - Charlene Babra Waryah
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
- Department of Medicine and Cell Biology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Paul Costantino
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
| | - Hani Al-Salami
- School of Pharmacy, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
| | - Sangeetha Mathavan
- School of Pharmacy, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
| | - Kelsi Wells
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
| | - Harish Kumar Tiwari
- School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, Australia
| | | | - Shrikrishna Isloor
- Veterinary College, Karnataka Veterinary, Animal and Fisheries Sciences University, Bangalore, India
| | | | - Trilochan Mukkur
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, Perth, Western Australia, Australia
- * E-mail:
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74
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Cyclic di-AMP Released from Staphylococcus aureus Biofilm Induces a Macrophage Type I Interferon Response. Infect Immun 2016; 84:3564-3574. [PMID: 27736778 PMCID: PMC5116733 DOI: 10.1128/iai.00447-16] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 10/01/2016] [Indexed: 12/14/2022] Open
Abstract
Staphylococcus aureus is a leading cause of community- and nosocomial-acquired infections, with a propensity for biofilm formation. S. aureus biofilms actively skew the host immune response toward an anti-inflammatory state; however, the biofilm effector molecules and the mechanism(s) of action responsible for this phenomenon remain to be fully defined. The essential bacterial second messenger cyclic diadenylate monophosphate (c-di-AMP) is an emerging pathogen-associated molecular pattern during intracellular bacterial infections, as c-di-AMP secretion into the infected host cytosol induces a robust type I interferon (IFN) response. Type I IFNs have the potential to exacerbate infectious outcomes by promoting anti-inflammatory effects; however, the type I IFN response to S. aureus biofilms is unknown. Additionally, while several intracellular proteins function as c-di-AMP receptors in S. aureus, it has yet to be determined if any extracellular role for c-di-AMP exists and its release during biofilm formation has not yet been demonstrated. This study examined the possibility that c-di-AMP released during S. aureus biofilm growth polarizes macrophages toward an anti-inflammatory phenotype via type I interferon signaling. DacA, the enzyme responsible for c-di-AMP synthesis in S. aureus, was highly expressed during biofilm growth, and 30 to 50% of total c-di-AMP produced from S. aureus biofilm was released extracellularly due to autolytic activity. S. aureus biofilm c-di-AMP release induced macrophage type I IFN expression via a STING-dependent pathway and promoted S. aureus intracellular survival in macrophages. These findings identify c-di-AMP as another mechanism for how S. aureus biofilms promote macrophage anti-inflammatory activity, which likely contributes to biofilm persistence.
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Lee S, Kivimäe S, Dolor A, Szoka FC. Macrophage-based cell therapies: The long and winding road. J Control Release 2016; 240:527-540. [PMID: 27422609 PMCID: PMC5064880 DOI: 10.1016/j.jconrel.2016.07.018] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 07/09/2016] [Accepted: 07/11/2016] [Indexed: 12/13/2022]
Abstract
In the quest for better medicines, attention is increasingly turning to cell-based therapies. The rationale is that infused cells can provide a targeted therapy to precisely correct a complex disease phenotype. Between 1987 and 2010, autologous macrophages (MΦs) were used in clinical trials to treat a variety of human tumors; this approach provided a modest therapeutic benefit in some patients but no lasting remissions. These trials were initiated prior to an understanding of: the complexity of MΦ phenotypes, their ability to alter their phenotype in response to various cytokines and/or the environment, and the extent of survival of the re-infused MΦs. It is now known that while inflammatory MΦs can kill tumor cells, the tumor environment is able to reprogram MΦs into a tumorigenic phenotype; inducing blood vessel formation and contributing to a cancer cell growth-promoting milieu. We review how new information enables the development of large numbers of ex vivo generated MΦs, and how conditioning and gene engineering strategies are used to restrict the MΦ to an appropriate phenotype or to enable production of therapeutic proteins. We survey applications in which the MΦ is loaded with nanomedicines, such as liposomes ex vivo, so when the drug-loaded MΦs are infused into an animal, the drug is released at the disease site. Finally, we also review the current status of MΦ biodistribution and survival after transplantation into an animal. The combination of these recent advances opens the way for improved MΦ cell therapies.
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Affiliation(s)
- Simon Lee
- The UC-Berkeley-UCSF Graduate Program in Bioengineering, University of California Berkeley, Berkeley 94720, USA
| | - Saul Kivimäe
- Department of Bioengineering, Therapeutic Sciences and Pharmaceutical Chemistry, University of California San Francisco, San Francisco 94143, USA
| | - Aaron Dolor
- Department of Bioengineering, Therapeutic Sciences and Pharmaceutical Chemistry, University of California San Francisco, San Francisco 94143, USA
| | - Francis C Szoka
- The UC-Berkeley-UCSF Graduate Program in Bioengineering, University of California Berkeley, Berkeley 94720, USA; Department of Bioengineering, Therapeutic Sciences and Pharmaceutical Chemistry, University of California San Francisco, San Francisco 94143, USA.
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Versatility of Biofilm Matrix Molecules in Staphylococcus epidermidis Clinical Isolates and Importance of Polysaccharide Intercellular Adhesin Expression during High Shear Stress. mSphere 2016; 1:mSphere00165-16. [PMID: 27747298 PMCID: PMC5064449 DOI: 10.1128/msphere.00165-16] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 09/20/2016] [Indexed: 01/13/2023] Open
Abstract
Staphylococcus epidermidis is a leading cause of infections related to biomaterials, mostly due to their ability to form biofilm. Biofilm accumulation mechanisms vary, including those that are dependent on specific proteins, environmental DNA (eDNA), or polysaccharide intercellular adhesin (PIA). We found that those isolates obtained from high-shear environments, such as the lumen of a catheter, are more likely to produce PIA-mediated biofilms than those isolates obtained from a low-shear biomaterial-related infection. This suggests that PIA functions as a mechanism that is protective against shear flow. Finally, we performed selection experiments documenting the heterogeneity of biofilm accumulation molecules that function in the absence of PIA, further documenting the biofilm-forming potential of S. epidermidis. Staphylococcus epidermidis is a leading cause of hospital-associated infections, including those of intravascular catheters, cerebrospinal fluid shunts, and orthopedic implants. Multiple biofilm matrix molecules with heterogeneous characteristics have been identified, including proteinaceous, polysaccharide, and nucleic acid factors. Two of the best-studied components in S. epidermidis include accumulation-associated protein (Aap) and polysaccharide intercellular adhesin (PIA), produced by the enzymatic products of the icaADBC operon. Biofilm composition varies by strain as well as environmental conditions, and strains producing PIA-mediated biofilms are more robust. Clinically, biofilm-mediated infections occur in a variety of anatomical sites with diverse physiological properties. To test the hypothesis that matrix composition exhibits niche specificity, biofilm-related genetic and physical properties were compared between S. epidermidis strains isolated from high-shear and low-shear environments. Among a collection of 105 clinical strains, significantly more isolates from high-shear environments carried the icaADBC operon than did those from low-shear settings (43.9% versus 22.9%, P < 0.05), while there was no significant difference in the presence of aap (77.2% versus 75.0%, P > 0.05). Additionally, a significantly greater number of high-shear isolates were capable of forming biofilm in vitro in a microtiter assay (82.5% versus 45.8%, P < 0.0001). However, even among high-shear clinical isolates, less than half contained the icaADBC locus; therefore, we selected for ica-negative variants with increased attachment to abiotic surfaces to examine PIA-independent biofilm mechanisms. Sequencing of selected variants identified substitutions capable of enhancing biofilm formation in multiple genes, further highlighting the heterogeneity of S. epidermidis biofilm molecules and mechanisms. IMPORTANCEStaphylococcus epidermidis is a leading cause of infections related to biomaterials, mostly due to their ability to form biofilm. Biofilm accumulation mechanisms vary, including those that are dependent on specific proteins, environmental DNA (eDNA), or polysaccharide intercellular adhesin (PIA). We found that those isolates obtained from high-shear environments, such as the lumen of a catheter, are more likely to produce PIA-mediated biofilms than those isolates obtained from a low-shear biomaterial-related infection. This suggests that PIA functions as a mechanism that is protective against shear flow. Finally, we performed selection experiments documenting the heterogeneity of biofilm accumulation molecules that function in the absence of PIA, further documenting the biofilm-forming potential of S. epidermidis.
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Chen J, Howell C, Haller CA, Patel MS, Ayala P, Moravec KA, Dai E, Liu L, Sotiri I, Aizenberg M, Aizenberg J, Chaikof EL. An immobilized liquid interface prevents device associated bacterial infection in vivo. Biomaterials 2016; 113:80-92. [PMID: 27810644 DOI: 10.1016/j.biomaterials.2016.09.028] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 09/20/2016] [Accepted: 09/30/2016] [Indexed: 12/16/2022]
Abstract
Virtually all biomaterials are susceptible to biofilm formation and, as a consequence, device-associated infection. The concept of an immobilized liquid surface, termed slippery liquid-infused porous surfaces (SLIPS), represents a new framework for creating a stable, dynamic, omniphobic surface that displays ultralow adhesion and limits bacterial biofilm formation. A widely used biomaterial in clinical care, expanded polytetrafluoroethylene (ePTFE), infused with various perfluorocarbon liquids generated SLIPS surfaces that exhibited a 99% reduction in S. aureus adhesion with preservation of macrophage viability, phagocytosis, and bactericidal function. Notably, SLIPS modification of ePTFE prevents device infection after S. aureus challenge in vivo, while eliciting a significantly attenuated innate immune response. SLIPS-modified implants also decrease macrophage inflammatory cytokine expression in vitro, which likely contributed to the presence of a thinner fibrous capsule in the absence of bacterial challenge. SLIPS is an easily implementable technology that provides a promising approach to substantially reduce the risk of device infection and associated patient morbidity, as well as health care costs.
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Affiliation(s)
- Jiaxuan Chen
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States; Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States
| | - Caitlin Howell
- Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States; John A. Paulson School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, MA 02138, United States
| | - Carolyn A Haller
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States; Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States
| | - Madhukar S Patel
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States; Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States; Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114, United States
| | - Perla Ayala
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States; Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States
| | - Katherine A Moravec
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States
| | - Erbin Dai
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States
| | - Liying Liu
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States
| | - Irini Sotiri
- Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States; John A. Paulson School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, MA 02138, United States
| | - Michael Aizenberg
- Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States
| | - Joanna Aizenberg
- Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States; John A. Paulson School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, MA 02138, United States; Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, United States; Kavli Institute for Bionano Science and Technology, Harvard University, 29 Oxford Street, Cambridge, MA 02138, United States.
| | - Elliot L Chaikof
- Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States; Wyss Institute for Biologically Inspired Engineering at Harvard University, 3 Blackfan Circle, Boston, MA 02115, United States; Harvard-MIT Division of Health Sciences and Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, United States.
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Watters C, Fleming D, Bishop D, Rumbaugh KP. Host Responses to Biofilm. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 142:193-239. [PMID: 27571696 DOI: 10.1016/bs.pmbts.2016.05.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
From birth to death the human host immune system interacts with bacterial cells. Biofilms are communities of microbes embedded in matrices composed of extracellular polymeric substance (EPS), and have been implicated in both the healthy microbiome and disease states. The immune system recognizes many different bacterial patterns, molecules, and antigens, but these components can be camouflaged in the biofilm mode of growth. Instead, immune cells come into contact with components of the EPS matrix, a diverse, hydrated mixture of extracellular DNA (bacterial and host), proteins, polysaccharides, and lipids. As bacterial cells transition from planktonic to biofilm-associated they produce small molecules, which can increase inflammation, induce cell death, and even cause necrosis. To survive, invading bacteria must overcome the epithelial barrier, host microbiome, complement, and a variety of leukocytes. If bacteria can evade these initial cell populations they have an increased chance at surviving and causing ongoing disease in the host. Planktonic cells are readily cleared, but biofilms reduce the effectiveness of both polymorphonuclear neutrophils and macrophages. In addition, in the presence of these cells, biofilm formation is actively enhanced, and components of host immune cells are assimilated into the EPS matrix. While pathogenic biofilms contribute to states of chronic inflammation, probiotic Lactobacillus biofilms cause a negligible immune response and, in states of inflammation, exhibit robust antiinflammatory properties. These probiotic biofilms colonize and protect the gut and vagina, and have been implicated in improved healing of damaged skin. Overall, biofilms stimulate a unique immune response that we are only beginning to understand.
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Affiliation(s)
- C Watters
- Wound Infections Department, Naval Medical Research Center, Silver Spring, MD, United States
| | - D Fleming
- Department of Surgery, Texas Tech University Health Sciences Center, Lubbock, TX, United States; Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - D Bishop
- Wound Infections Department, Naval Medical Research Center, Silver Spring, MD, United States
| | - K P Rumbaugh
- Department of Surgery, Texas Tech University Health Sciences Center, Lubbock, TX, United States; Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX, United States.
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McCarthy H, Waters EM, Bose JL, Foster S, Bayles KW, O'Neill E, Fey PD, O'Gara JP. The major autolysin is redundant for Staphylococcus aureus USA300 LAC JE2 virulence in a murine device-related infection model. FEMS Microbiol Lett 2016; 363:fnw087. [PMID: 27044299 DOI: 10.1093/femsle/fnw087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2016] [Indexed: 12/14/2022] Open
Abstract
The major Staphylococcus aureus autolysin, Atl, has been implicated in attachment to surfaces and release of extracellular DNA during biofilm formation under laboratory conditions. Consistent with this, polyclonal antibodies to the amidase and glucosaminidase domains of Atl inhibited in vitro biofilm formation. However, in a murine model of device-related infection the community-associated S. aureus strain USA300 LAC JE2 established a successful infection in the absence of atl These data indicate that Atl activity is not required for biofilm production in this infection model and reveal the importance of characterizing the contribution of biofilm phenotypes to virulence under in vivo conditions.
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Affiliation(s)
- Hannah McCarthy
- Department of Microbiology, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Elaine M Waters
- Department of Pathology and Microbiology, Center for Staphylococcal Research, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - Jeffrey L Bose
- Department of Pathology and Microbiology, Center for Staphylococcal Research, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - Simon Foster
- Department of Molecular Biology and Biotechnology, The Krebs Institute, University of Sheffield, Sheffield S10 2TN, UK
| | - Kenneth W Bayles
- Department of Pathology and Microbiology, Center for Staphylococcal Research, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - Eoghan O'Neill
- Department of Clinical Microbiology, Royal College of Surgeons in Ireland, Connolly Hospital, Dublin 15, Ireland
| | - Paul D Fey
- Department of Pathology and Microbiology, Center for Staphylococcal Research, University of Nebraska Medical Center, Omaha, NE 68198-5900, USA
| | - James P O'Gara
- Department of Microbiology, School of Natural Sciences, National University of Ireland, Galway, Ireland
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80
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Capelletti RV, Moraes ÂM. Waterborne microorganisms and biofilms related to hospital infections: strategies for prevention and control in healthcare facilities. JOURNAL OF WATER AND HEALTH 2016; 14:52-67. [PMID: 26837830 DOI: 10.2166/wh.2015.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Water is the main stimulus for the development of microorganisms, and its flow has an important role in the spreading of contaminants. In hospitals, the water distribution system requires special attention since it can be a source of pathogens, including those in the form of biofilms often correlated with resistance of microorganisms to various treatments. In this paper, information relevant to cases of nosocomial infections involving water circuits as a source of contaminants is compiled, with emphasis on the importance of microbiological control strategies to prevent the installation, spreading and growth of microorganisms in hospitals. An overview of the worldwide situation is provided, with emphasis on Brazilian hospitals. Different approaches normally used to control the occurrence of nosocomial infections due to waterborne contaminants are analyzed, and the use of the polysaccharide chitosan for this specific application is briefly discussed.
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Affiliation(s)
- Raquel Vannucci Capelletti
- Department of Engineering of Materials and of Bioprocesses, School of Chemical Engineering, University of Campinas (UNICAMP), CEP 13083-852, Campinas, São Paulo, Brazil E-mail:
| | - Ângela Maria Moraes
- Department of Engineering of Materials and of Bioprocesses, School of Chemical Engineering, University of Campinas (UNICAMP), CEP 13083-852, Campinas, São Paulo, Brazil E-mail:
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Flannagan RS, Heit B, Heinrichs DE. Antimicrobial Mechanisms of Macrophages and the Immune Evasion Strategies of Staphylococcus aureus. Pathogens 2015; 4:826-68. [PMID: 26633519 PMCID: PMC4693167 DOI: 10.3390/pathogens4040826] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 11/17/2015] [Accepted: 11/24/2015] [Indexed: 12/21/2022] Open
Abstract
Habitually professional phagocytes, including macrophages, eradicate microbial invaders from the human body without overt signs of infection. Despite this, there exist select bacteria that are professional pathogens, causing significant morbidity and mortality across the globe and Staphylococcus aureus is no exception. S. aureus is a highly successful pathogen that can infect virtually every tissue that comprises the human body causing a broad spectrum of diseases. The profound pathogenic capacity of S. aureus can be attributed, in part, to its ability to elaborate a profusion of bacterial effectors that circumvent host immunity. Macrophages are important professional phagocytes that contribute to both the innate and adaptive immune response, however from in vitro and in vivo studies, it is evident that they fail to eradicate S. aureus. This review provides an overview of the antimicrobial mechanisms employed by macrophages to combat bacteria and describes the immune evasion strategies and some representative effectors that enable S. aureus to evade macrophage-mediated killing.
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Affiliation(s)
- Ronald S Flannagan
- Department of Microbiology and Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
| | - Bryan Heit
- Department of Microbiology and Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
- Centre for Human Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
| | - David E Heinrichs
- Department of Microbiology and Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
- Centre for Human Immunology, the University of Western Ontario, London, ON N6A 5C1, Canada.
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82
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Bhattacharya M, Wozniak DJ, Stoodley P, Hall-Stoodley L. Prevention and treatment of Staphylococcus aureus biofilms. Expert Rev Anti Infect Ther 2015; 13:1499-516. [PMID: 26646248 DOI: 10.1586/14787210.2015.1100533] [Citation(s) in RCA: 168] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
S. aureus colonizes both artificial and tissue surfaces in humans causing chronic persistent infections that are difficult to cure. It is a notorious pathogen due to its antibiotic recalcitrance and phenotypic adaptability, both of which are facilitated by its ability to develop biofilms. S. aureus biofilms challenge conventional anti-infective approaches, most notably antibiotic therapy. Therefore there is an unmet need to develop and include parallel approaches that target S. aureus biofilm infections. This review discusses two broad anti-infective strategies: (1) preventative approaches (anti-biofilm surface coatings, the inclusion of biofilm-specific vaccine antigens); and (2) approaches aimed at eradicating established S. aureus biofilms, particularly those associated with implant infections. Advances in understanding the distinct nature of S. aureus biofilm development and pathogenesis have led to growing optimism in S. aureus biofilm targeted anti-infective strategies. Further research is needed however, to see the successful administration and validation of these approaches to the diverse types of infections caused by S. aureus biofilms from multiple clinical strains.
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Affiliation(s)
- Mohini Bhattacharya
- a Department of Microbiology , The Ohio State University , Columbus , OH , USA
| | - Daniel J Wozniak
- a Department of Microbiology , The Ohio State University , Columbus , OH , USA.,b Department of Microbial Infection and Immunity , The Ohio State University College of Medicine , Columbus , OH , USA.,c The Center for Microbial Interface Biology, The Ohio State University , Columbus , OH , USA
| | - Paul Stoodley
- b Department of Microbial Infection and Immunity , The Ohio State University College of Medicine , Columbus , OH , USA.,c The Center for Microbial Interface Biology, The Ohio State University , Columbus , OH , USA.,d Department of Orthopedics , The Ohio State University College of Medicine , Columbus , OH , USA.,e Department of Engineering Sciences, National Centre for Advanced Tribology at Southampton (nCATS) , University of Southampton , Southampton , UK
| | - Luanne Hall-Stoodley
- b Department of Microbial Infection and Immunity , The Ohio State University College of Medicine , Columbus , OH , USA.,c The Center for Microbial Interface Biology, The Ohio State University , Columbus , OH , USA
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Immunomodulation and Disease Tolerance to Staphylococcus aureus. Pathogens 2015; 4:793-815. [PMID: 26580658 PMCID: PMC4693165 DOI: 10.3390/pathogens4040793] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 11/10/2015] [Indexed: 12/12/2022] Open
Abstract
The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and disease tolerance mechanisms that promote commensalism to S. aureus.
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84
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Batoni G, Maisetta G, Esin S. Antimicrobial peptides and their interaction with biofilms of medically relevant bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1858:1044-60. [PMID: 26525663 DOI: 10.1016/j.bbamem.2015.10.013] [Citation(s) in RCA: 233] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/16/2015] [Accepted: 10/18/2015] [Indexed: 02/07/2023]
Abstract
Biofilm-associated infections represent one of the major threats of modern medicine. Biofilm-forming bacteria are encased in a complex mixture of extracellular polymeric substances (EPS) and acquire properties that render them highly tolerant to conventional antibiotics and host immune response. Therefore, there is a pressing demand of new drugs active against microbial biofilms. In this regard, antimicrobial peptides (AMPs) represent an option taken increasingly in consideration. After dissecting the peculiar biofilm features that may greatly affect the development of new antibiofilm drugs, the present article provides a general overview of the rationale behind the use of AMPs against biofilms of medically relevant bacteria and on the possible mechanisms of AMP-antibiofilm activity. An analysis of the interactions of AMPs with biofilm components, especially those constituting the EPS, and the obstacles and/or opportunities that may arise from such interactions in the development of new AMP-based antibiofilm strategies is also presented and discussed. This article is part of a Special Issue entitled: Antimicrobial Peptides edited by Karl Lohner and Kai Hilpert.
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Affiliation(s)
- Giovanna Batoni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
| | - Giuseppantonio Maisetta
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Semih Esin
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
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Sethi S, Thormann U, Sommer U, Stötzel S, Mohamed W, Schnettler R, Domann E, Chakraborty T, Alt V. Impact of prophylactic CpG Oligodeoxynucleotide application on implant-associated Staphylococcus aureus bone infection. Bone 2015; 78:194-202. [PMID: 25959416 DOI: 10.1016/j.bone.2015.04.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 04/17/2015] [Accepted: 04/21/2015] [Indexed: 01/09/2023]
Abstract
TLR-9 ligand CpG oligodeoxynucleotide type B (CpG ODN) induces a proinflammatory environment. We evaluated the effects of a preoperative CpG ODN application in an implant-associated Staphylococcus aureus bone infection model by monitoring bacterial loads and cytokine and chemokine levels. A total of 95 rats were used in four different groups: CpG ODN group (group 1; n=25), non-CpG-ODN group (group 2; n=25); saline pretreatment (group 3; n=25), and one uninfected group (group 4; n=20). A single dose of CpG-ODN was administered to the left tibialis anterior muscle 3days prior to surgery and the tibia midshaft was osteotomized, stabilized by an intramedullary implant and subsequently contaminated with 10(3) colony forming units (CFUs) of S. aureus in groups 1-3. The osteotomy gap in animals of group 4 was not contaminated with S. aureus and those animals did not receive any pretreatment. CpG ODN administration resulted in significant reduction of the bacterial load in tibia tissue homogenate and on the implant surface on day 1 post-infection compared to non-CpG-ODN pretreatment (p<0.05; p<0.05). Reductions in bacterial CFUs, compared to non-treated (saline) controls, were approximately 67% and 77% for bone tissue homogenates and implants. No bacteria were detected in uninfected rats. Early reduction of bacterial CFUs in the tibia was accompanied by increased levels of proinflammatory mediators MIP-2, IL-1β and RANTES in bone tissue milieu of the CpG ODN treated group compared to controls. At day 42 post-infection, bone marrow tissue of rats pretreated with CpG ODN had comparable high bacterial CFU numbers as the non-CpG ODN or saline treated groups. Microbiological analysis of implants removed from CpG ODN treated rats showed high bacterial growth densities on their surfaces which were not different from those observed in controls. In histology, all animals of groups 1-3 showed established infected non-unions. Additionally, inflammatory mediator profiles in bone marrow homogenates of CpG ODN treated rats resembled those seen in infected controls. In this rat model, prophylactic administration of a single dose of CpG ODN, resulted in marked reduction of S. aureus load in the infected tibia during the initial stage of infection but failed to prevent development of chronic infection over time.
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Affiliation(s)
- Shneh Sethi
- Institute of Medical Microbiology, Justus-Liebig-University Giessen, 35392 Giessen, Germany.
| | - Ulrich Thormann
- Department of Trauma Surgery Giessen, Justus-Liebig-University Giessen, 35392 Giessen, Germany
| | - Ursula Sommer
- Laboratory of Experimental Trauma Surgery, Justus-Liebig-University Giessen, 35392 Giessen, Germany
| | - Sabine Stötzel
- Laboratory of Experimental Trauma Surgery, Justus-Liebig-University Giessen, 35392 Giessen, Germany
| | - Walid Mohamed
- Laboratory of Experimental Trauma Surgery, Justus-Liebig-University Giessen, 35392 Giessen, Germany
| | - Reinhard Schnettler
- Department of Trauma Surgery Giessen, Justus-Liebig-University Giessen, 35392 Giessen, Germany
| | - Eugen Domann
- Institute of Medical Microbiology, Justus-Liebig-University Giessen, 35392 Giessen, Germany
| | - Trinad Chakraborty
- Institute of Medical Microbiology, Justus-Liebig-University Giessen, 35392 Giessen, Germany
| | - Volker Alt
- Department of Trauma Surgery Giessen, Justus-Liebig-University Giessen, 35392 Giessen, Germany
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A Multiple Antigenic Peptide Mimicking Peptidoglycan Induced T Cell Responses to Protect Mice from Systemic Infection with Staphylococcus aureus. PLoS One 2015; 10:e0136888. [PMID: 26317210 PMCID: PMC4552945 DOI: 10.1371/journal.pone.0136888] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 08/10/2015] [Indexed: 12/11/2022] Open
Abstract
Due to the enormous capacity of Staphylococcus aureus to acquire antibiotic resistance, it becomes imperative to develop vaccines for decreasing the risk of its life-threatening infections. Peptidoglycan (PGN) is a conserved and major component of S. aureus cell wall. However, it has not been used as a vaccine candidate since it is a thymus-independent antigen. In this study, we synthesized a multiple antigenic peptide, named MAP27, which comprised four copies of a peptide that mimics the epitope of PGN. After immunization with MAP27 five times and boosting with heat-inactivated bacterium one time, anti-MAP27 serum bound directly to S. aureus or PGN. Immunization with MAP27 decreased the bacterial burden in organs of BALB/c mice and significantly prolonged their survival time after S. aureus lethal-challenge. The percentage of IFN-γ+CD3+ T cells and IL-17+CD4+ T cells in spleen, as well as the levels of IFN-γ, IL-17A/F and CCL3 in spleen and lung, significantly increased in the MAP27-immunized mice after infection. Moreover, in vitro incubation of heat-inactivated S. aureus with splenocytes isolated from MAP27-immunized mice stimulated the production of IFN-γ and IL-17A/F. Our findings demonstrated that MAP27, as a thymus-dependent antigen, is efficient at eliciting T cell-mediated responses to protect mice from S. aureus infection. This study sheds light on a possible strategy to design vaccines against S. aureus.
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87
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Staphylococcus aureus Biofilms Induce Macrophage Dysfunction Through Leukocidin AB and Alpha-Toxin. mBio 2015; 6:mBio.01021-15. [PMID: 26307164 PMCID: PMC4550693 DOI: 10.1128/mbio.01021-15] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The macrophage response to planktonic Staphylococcus aureus involves the induction of proinflammatory microbicidal activity. However, S. aureus biofilms can interfere with these responses in part by polarizing macrophages toward an anti-inflammatory profibrotic phenotype. Here we demonstrate that conditioned medium from mature S. aureus biofilms inhibited macrophage phagocytosis and induced cytotoxicity, suggesting the involvement of a secreted factor(s). Iterative testing found the active factor(s) to be proteinaceous and partially agr-dependent. Quantitative mass spectrometry identified alpha-toxin (Hla) and leukocidin AB (LukAB) as critical molecules secreted by S. aureus biofilms that inhibit murine macrophage phagocytosis and promote cytotoxicity. A role for Hla and LukAB was confirmed by using hla and lukAB mutants, and synergy between the two toxins was demonstrated with a lukAB hla double mutant and verified by complementation. Independent confirmation of the effects of Hla and LukAB on macrophage dysfunction was demonstrated by using an isogenic strain in which Hla was constitutively expressed, an Hla antibody to block toxin activity, and purified LukAB peptide. The importance of Hla and LukAB during S. aureus biofilm formation in vivo was assessed by using a murine orthopedic implant biofilm infection model in which the lukAB hla double mutant displayed significantly lower bacterial burdens and more macrophage infiltrates than each single mutant. Collectively, these findings reveal a critical synergistic role for Hla and LukAB in promoting macrophage dysfunction and facilitating S. aureus biofilm development in vivo. Staphylococcus aureus has a propensity to form multicellular communities known as biofilms. While growing in a biofilm, S. aureus displays increased tolerance to nutrient deprivation, antibiotic insult, and even host immune challenge. Previous studies have shown that S. aureus biofilms thwart host immunity in part by preventing macrophage phagocytosis. It remained unclear whether this was influenced solely by the considerable size of biofilms or whether molecules were also actively secreted to circumvent macrophage-mediated phagocytosis. This is the first report to demonstrate that S. aureus biofilms inhibit macrophage phagocytosis and induce macrophage death through the combined action of leukocidin AB and alpha-toxin. Loss of leukocidin AB and alpha-toxin expression resulted in enhanced S. aureus biofilm clearance in a mouse model of orthopedic implant infection, suggesting that these toxins could be targeted therapeutically to facilitate biofilm clearance in humans.
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88
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Heim CE, Vidlak D, Kielian T. Interleukin-10 production by myeloid-derived suppressor cells contributes to bacterial persistence during Staphylococcus aureus orthopedic biofilm infection. J Leukoc Biol 2015; 98:1003-13. [PMID: 26232453 DOI: 10.1189/jlb.4vma0315-125rr] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/09/2015] [Indexed: 12/18/2022] Open
Abstract
Staphylococcus aureus is known to establish biofilms on medical devices. We recently demonstrated that Ly6G(high)Ly6C(+) myeloid-derived suppressor cells are critical for allowing S. aureus biofilms to subvert immune-mediated clearance; however, the mechanisms whereby myeloid-derived suppressor cells promote biofilm persistence remain unknown. Interleukin-10 expression was significantly increased in a mouse model of S. aureus orthopedic implant biofilm infection with kinetics that mirrored myeloid-derived suppressor cell recruitment. Because myeloid-derived suppressor cells produce interleukin-10, we explored whether it was involved in orchestrating the nonproductive immune response that facilitates biofilm formation. Analysis of interleukin-10-green fluorescent protein reporter mice revealed that Ly6G(high)Ly6C(+) myeloid-derived suppressor cells were the main source of interleukin-10 during the first 2 wk of biofilm infection, whereas monocytes had negligible interleukin-10 expression until day 14. Myeloid-derived suppressor cell influx into implant-associated tissues was significantly reduced in interleukin-10 knockout mice at day 14 postinfection, concomitant with increased monocyte and macrophage infiltrates that displayed enhanced proinflammatory gene expression. Reduced myeloid-derived suppressor cell recruitment facilitated bacterial clearance, as revealed by significant decreases in S. aureus burdens in the knee joint, surrounding soft tissue, and femur of interleukin-10 knockout mice. Adoptive transfer of interleukin-10 wild-type myeloid-derived suppressor cells into S. aureus-infected interleukin-10 knockout mice restored the local biofilm-permissive environment, as evidenced by increased bacterial burdens and inhibition of monocyte proinflammatory activity. These effects were both interleukin-10-dependent and interleukin-10-independent because myeloid-derived suppressor cell-derived interleukin-10 was required for promoting biofilm growth and anti-inflammatory gene expression in monocytes but was not involved in monocyte recruitment to biofilm-infected tissues. These results demonstrate that interleukin-10 production by myeloid-derived suppressor cells contributes to the persistence of S. aureus orthopedic biofilm infections.
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Affiliation(s)
- Cortney E Heim
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Debbie Vidlak
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
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89
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Abstract
ABSTRACT
The steps involved during the biofilm growth cycle include attachment to a substrate followed by more permanent adherence of the microorganisms, microcolony arrangement, and cell detachment required for the dissemination of single or clustered cells to other organ systems. Various methods have been developed for biofilm detection and quantitation. Biofilm-producing microorganisms can be detected in tissue culture plates, using silicone tubes and staining methods, and by visual assessment using scanning electron microscopy or confocal scanning laser microscopy. Quantitative measurement of biofilm growth is determined by using methods that include dry cell weight assays, colony-forming-unit counting, DNA quantification, or XTT 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide reduction assay. Upon infection, innate immune defense strategies are able to establish an immediate response through effector mechanisms mediated by immune cells, receptors, and several humoral factors. We present an overview of the life cycle of biofilms and their diversity, detection methods for biofilm development, and host immune responses to pathogens. We then focus on current concepts in bacterial and fungal biofilm immune evasion mechanisms. This appears to be of particular importance because the use of host immune responses may represent a novel therapeutic approach against biofilms.
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90
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Abstract
ABSTRACT
The steps involved during the biofilm growth cycle include attachment to a substrate followed by more permanent adherence of the microorganisms, microcolony arrangement, and cell detachment required for the dissemination of single or clustered cells to other organ systems. Various methods have been developed for biofilm detection and quantitation. Biofilm-producing microorganisms can be detected in tissue culture plates, using silicone tubes and staining methods, and by visual assessment using scanning electron microscopy or confocal scanning laser microscopy. Quantitative measurement of biofilm growth is determined by using methods that include dry cell weight assays, colony-forming-unit counting, DNA quantification, or XTT 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide reduction assay. Upon infection, innate immune defense strategies are able to establish an immediate response through effector mechanisms mediated by immune cells, receptors, and several humoral factors. We present an overview of the life cycle of biofilms and their diversity, detection methods for biofilm development, and host immune responses to pathogens. We then focus on current concepts in bacterial and fungal biofilm immune evasion mechanisms. This appears to be of particular importance because the use of host immune responses may represent a novel therapeutic approach against biofilms.
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91
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Pozzi C, Lofano G, Mancini F, Soldaini E, Speziale P, De Gregorio E, Rappuoli R, Bertholet S, Grandi G, Bagnoli F. Phagocyte subsets and lymphocyte clonal deletion behind ineffective immune response to Staphylococcus aureus. FEMS Microbiol Rev 2015; 39:750-63. [PMID: 25994610 DOI: 10.1093/femsre/fuv024] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2015] [Indexed: 01/14/2023] Open
Abstract
Lack of known mechanisms of protection against Staphylococcus aureus in humans is hindering development of efficacious vaccines. Preclinical as well as clinical data suggest that antibodies play an important role against S. aureus. For instance, certain hypogammaglobulinaemic patients are at increased risk of staphylococcal infections. However, development of effective humoral response may be dampened by converging immune-evasion mechanisms of S. aureus. We hypothesize that B-cell proliferation induced by staphylococcal protein A (SpA) and continuous antigen exposure, without the proper T-cell help and cytokine stimuli, leads to antigen-activated B-cell deletion and anergy. Recent findings suggest an important role of type I neutrophils (PMN-I) and conventionally activated macrophages (M1) against S. aureus, while alternatively activated macrophages (M2) favour biofilm persistence and sepsis. In addition, neutrophil-macrophage cooperation promotes extravasation and activation of neutrophils as well as clearance of bacteria ensnared in neutrophil extracellular traps. Activation of these processes is modulated by cytokines and T cells. Indeed, low CD4(+) T-cell counts represent an important risk factor for skin infections and bacteraemia in patients. Altogether, these observations could lead to the identification of predictive correlates of protection and ways for shifting the balance of the response to the benefit of the host through vaccination.
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Affiliation(s)
- Clarissa Pozzi
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
| | - Giuseppe Lofano
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
| | - Francesca Mancini
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
| | | | - Pietro Speziale
- Department of Molecular Medicine, Institute of Biochemistry, 27100 Pavia, Italy
| | - Ennio De Gregorio
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
| | - Rino Rappuoli
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
| | - Sylvie Bertholet
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
| | - Guido Grandi
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
| | - Fabio Bagnoli
- Novartis Vaccines, Research Center, via Fiorentina 1, 53100 Siena, Italy
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92
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Silva LCND, Alves NMP, Castro MCABD, Pereira VRA, Paz NVND, Coelho LCBB, Figueiredo RCBQD, Correia MTDS. Immunomodulatory effects of pCramoll and rCramoll on peritoneal exudate cells (PECs) infected and non-infected with Staphylococcus aureus. Int J Biol Macromol 2015; 72:848-54. [DOI: 10.1016/j.ijbiomac.2014.09.045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 09/25/2014] [Accepted: 09/30/2014] [Indexed: 01/16/2023]
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93
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Cole J, Aberdein J, Jubrail J, Dockrell DH. The role of macrophages in the innate immune response to Streptococcus pneumoniae and Staphylococcus aureus: mechanisms and contrasts. Adv Microb Physiol 2014; 65:125-202. [PMID: 25476766 DOI: 10.1016/bs.ampbs.2014.08.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Macrophages are critical mediators of innate immune responses against bacteria. The Gram-positive bacteria Streptococcus pneumoniae and Staphylococcus aureus express a range of virulence factors, which challenge macrophages' immune competence. We review how macrophages respond to this challenge. Macrophages employ a range of strategies to phagocytose and kill each pathogen. When the macrophages capacity to clear bacteria is overwhelmed macrophages play important roles in orchestrating the inflammatory response through pattern recognition receptor-mediated responses. Macrophages also ensure the inflammatory response is tightly constrained, to avoid tissue damage, and play an important role in downregulating the inflammatory response once initial bacterial replication is controlled.
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Affiliation(s)
- Joby Cole
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom
| | - Jody Aberdein
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom
| | - Jamil Jubrail
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom
| | - David H Dockrell
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom.
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94
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Foreign Body Infection Models to Study Host-Pathogen Response and Antimicrobial Tolerance of Bacterial Biofilm. Antibiotics (Basel) 2014; 3:378-97. [PMID: 27025752 PMCID: PMC4790362 DOI: 10.3390/antibiotics3030378] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 07/01/2014] [Accepted: 08/06/2014] [Indexed: 12/13/2022] Open
Abstract
The number of implanted medical devices is steadily increasing and has become an effective intervention improving life quality, but still carries the risk of infection. These infections are mainly caused by biofilm-forming staphylococci that are difficult to treat due to the decreased susceptibility to both antibiotics and host defense mechanisms. To understand the particular pathogenesis and treatment tolerance of implant-associated infection (IAI) animal models that closely resemble human disease are needed. Applications of the tissue cage and catheter abscess foreign body infection models in the mouse will be discussed herein. Both models allow the investigation of biofilm and virulence of various bacterial species and a comprehensive insight into the host response at the same time. They have also been proven to serve as very suitable tools to study the anti-adhesive and anti-infective efficacy of different biomaterial coatings. The tissue cage model can additionally be used to determine pharmacokinetics, efficacy and cytotoxicity of antimicrobial compounds as the tissue cage fluid can be aspirated repeatedly without the need to sacrifice the animal. Moreover, with the advance in innovative imaging systems in rodents, these models may offer new diagnostic measures of infection. In summary, animal foreign body infection models are important tools in the development of new antimicrobials against IAI and can help to elucidate the complex interactions between bacteria, the host immune system, and prosthetic materials.
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95
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Gutierrez-Murgas Y, Snowden JN. Ventricular shunt infections: immunopathogenesis and clinical management. J Neuroimmunol 2014; 276:1-8. [PMID: 25156073 DOI: 10.1016/j.jneuroim.2014.08.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/17/2014] [Accepted: 08/06/2014] [Indexed: 12/22/2022]
Abstract
Ventricular shunts are the most common neurosurgical procedure performed in the United States. This hydrocephalus treatment is often complicated by infection of the device with biofilm-forming bacteria. In this review, we discuss the pathogenesis of shunt infection, as well as the implications of the biofilm formation on treatment and prevention of these infections. Many questions remain, including the contribution of glia and the impact of inflammation on developmental outcomes following infection. Immune responses within the CNS must be carefully regulated to contain infection while minimizing bystander damage; further study is needed to design optimal treatment strategies for these patients.
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Affiliation(s)
- Yenis Gutierrez-Murgas
- Department of Pathology & Microbiology, University of Nebraska Medical Center, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, USA.
| | - Jessica N Snowden
- Department of Pathology & Microbiology, University of Nebraska Medical Center, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, USA; Department of Pediatrics, University of Nebraska Medical Center, 985900 Nebraska Medical Center, Omaha, NE 68198-5900, USA.
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96
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Morris MC, Gilliam EA, Button J, Li L. Dynamic modulation of innate immune response by varying dosages of lipopolysaccharide (LPS) in human monocytic cells. J Biol Chem 2014; 289:21584-90. [PMID: 24970893 DOI: 10.1074/jbc.m114.583518] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Innate monocytes and macrophages can be dynamically programmed into distinct states depending upon the strength of external stimuli. Innate programming may bear significant relevance to the pathogenesis and resolution of human inflammatory diseases. However, systems analyses with regard to the dynamic programming of innate leukocytes are lacking. In this study, we focused on the dynamic responses of human promonocytic THP-1 cells to lipopolysaccharide (LPS). We observed that varying dosages of LPS differentially modulate the expression of selected pro- and anti- inflammatory mediators such as IL-6 and IL-33. Super-low dosages of LPS preferentially induced the pro-inflammatory mediator IL-6, while higher dosages of LPS induced both IL-6 and IL-33. Mechanistically, we demonstrated that super-low and high doses of LPS cause differential activation of GSK3 and Akt, as well as the transcription factors FoxO1 and CREB. Inhibition of GSK3 enabled THP-1 cells to express IL-33 when challenged with super-low dose LPS. On the other hand, activation of CREB with adenosine suppressed IL-6 expression. Taken together, our study reveals a dynamic modulation of monocytic cells in response to varying dosages of endotoxin, and may shed light on our understanding of the dynamic balance that controls pathogenesis and resolution of inflammatory diseases.
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Affiliation(s)
- Matthew C Morris
- From the Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 and
| | | | - Julia Button
- From the Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 and
| | - Liwu Li
- From the Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 and the Virginia Tech Carillion School of Medicine, Roanoke, Virginia 24016
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97
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Abstract
In this review, we examine the current status of Staphylococcus aureus vaccine development and the prospects for future vaccines. Examination of the clinical trials to date show that murine models have not predicted success in humans for active or passive immunization. A key factor in the failure to develop a vaccine to prevent S. aureus infections comes from our relatively limited knowledge of human protective immunity. More recent reports on the elements of the human immune response to staphylococci are analysed. In addition, there is some controversy concerning the role of antibodies for protecting humans, and these data are reviewed. From a review of the current state of understanding of staphylococcal immunity, a working model is proposed. Some new work has provided some initial candidate biomarker(s) to predict outcomes of invasive infections and to predict the efficacy of antibiotic therapy in humans. We conclude by looking to the future through the perspective of lessons gleaned from the clinical vaccine trials.
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Affiliation(s)
- Vance G. Fowler
- Division of Infectious Diseases Duke University Medical Center Durham, NC 27710
| | - Richard A. Proctor
- University of Wisconsin School of Medicine and Public Health Madison, WI
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98
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Labonte AC, Tosello-Trampont AC, Hahn YS. The role of macrophage polarization in infectious and inflammatory diseases. Mol Cells 2014; 37:275-85. [PMID: 24625576 PMCID: PMC4012075 DOI: 10.14348/molcells.2014.2374] [Citation(s) in RCA: 262] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 12/16/2013] [Indexed: 02/08/2023] Open
Abstract
Macrophages, found in circulating blood as well as integrated into several tissues and organs throughout the body, represent an important first line of defense against disease and a necessary component of healthy tissue homeostasis. Additionally, macrophages that arise from the differentiation of monocytes recruited from the blood to inflamed tissues play a central role in regulating local inflammation. Studies of macrophage activation in the last decade or so have revealed that these cells adopt a staggering range of phenotypes that are finely tuned responses to a variety of different stimuli, and that the resulting subsets of activated macrophages play critical roles in both progression and resolution of disease. This review summarizes the current understanding of the contributions of differentially polarized macrophages to various infectious and inflammatory diseases and the ongoing effort to develop novel therapies that target this key aspect of macrophage biology.
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Affiliation(s)
- Adam C. Labonte
- Department of Microbiology, Beirne B. Carter Center for Immunology Research, University of Virginia,
USA
| | | | - Young S. Hahn
- Department of Microbiology, Beirne B. Carter Center for Immunology Research, University of Virginia,
USA
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99
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Heim CE, Vidlak D, Scherr TD, Kozel JA, Holzapfel M, Muirhead DE, Kielian T. Myeloid-derived suppressor cells contribute to Staphylococcus aureus orthopedic biofilm infection. THE JOURNAL OF IMMUNOLOGY 2014; 192:3778-92. [PMID: 24646737 DOI: 10.4049/jimmunol.1303408] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature monocytes and granulocytes that are potent inhibitors of T cell activation. A role for MDSCs in bacterial infections has only recently emerged, and nothing is known about MDSC function in the context of Staphylococcus aureus infection. Because S. aureus biofilms are capable of subverting immune-mediated clearance, we examined whether MDSCs could play a role in this process. CD11b(+)Gr-1(+) MDSCs represented the main cellular infiltrate during S. aureus orthopedic biofilm infection, accounting for >75% of the CD45+ population. Biofilm-associated MDSCs inhibited T cell proliferation and cytokine production, which correlated with a paucity of T cell infiltrates at the infection site. Analysis of FACS-purified MDSCs recovered from S. aureus biofilms revealed increased arginase-1, inducible NO synthase, and IL-10 expression, key mediators of MDSC suppressive activity. Targeted depletion of MDSCs and neutrophils using the mAb 1A8 (anti-Ly6G) improved bacterial clearance by enhancing the intrinsic proinflammatory attributes of infiltrating monocytes and macrophages. Furthermore, the ability of monocytes/macrophages to promote biofilm clearance in the absence of MDSC action was revealed with RB6-C85 (anti-Gr-1 or anti-Ly6G/Ly6C) administration, which resulted in significantly increased S. aureus burdens both locally and in the periphery, because effector Ly 6C monocytes and, by extension, mature macrophages were also depleted. Collectively, these results demonstrate that MDSCs are key contributors to the chronicity of S. aureus biofilm infection, as their immunosuppressive function prevents monocyte/macrophage proinflammatory activity, which facilitates biofilm persistence.
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Affiliation(s)
- Cortney E Heim
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198
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100
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Scherr TD, Heim CE, Morrison JM, Kielian T. Hiding in Plain Sight: Interplay between Staphylococcal Biofilms and Host Immunity. Front Immunol 2014; 5:37. [PMID: 24550921 PMCID: PMC3913997 DOI: 10.3389/fimmu.2014.00037] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 01/22/2014] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus and Staphylococcus epidermidis are notable for their propensity to form biofilms on implanted medical devices. Staphylococcal biofilm infections are typified by their recalcitrance to antibiotics and ability to circumvent host immune-mediated clearance, resulting in the establishment of chronic infections that are often recurrent in nature. Indeed, the immunomodulatory lifestyle of biofilms seemingly shapes the host immune response to ensure biofilm engraftment and persistence in an immune competent host. Here, we provide a brief review of the mechanisms whereby S. aureus and S. epidermidis biofilms manipulate host–pathogen interactions and discuss the concept of microenvironment maintenance in infectious outcomes, as well as speculate how these findings pertain to the challenges of staphylococcal vaccine development.
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Affiliation(s)
- Tyler D Scherr
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
| | - Cortney E Heim
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
| | - John M Morrison
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center , Omaha, NE , USA
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