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Shmarina G, Pukhalskaya D, Shmarin V, Semykin S, Avakyan L, Krasovsky S, Goryainova A, Kostyuk S, Zinchenko R, Kashirskaya N. Burkholderia cepacia in cystic fibrosis children and adolescents: overall survival and immune alterations. Front Cell Infect Microbiol 2024; 14:1374318. [PMID: 39011515 PMCID: PMC11246859 DOI: 10.3389/fcimb.2024.1374318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 06/18/2024] [Indexed: 07/17/2024] Open
Abstract
Background In current literature there are only scarce data on the host inflammatory response during Burkholderia cepacia complex (Bcc) persistence. The primary objective of the present research was to carry out cross-sectional analyses of biomarkers and evaluate disease progression in cystic fibrosis (CF) patients with chronic Bcc infection and pathogen-free ones. The secondary aim was to assess prospectively overall survival of the study participants during up to 8 years of follow-up. Methods The study included 116 paediatric patients with CF; 47 CF patients were chronically infected with Bcc, and 69 individuals were Bcc free. Plasma and sputum biomarkers (neutrophil elastase, MMP-8, MMP-9, MMP-12, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, IL-22, IL-23, IL-17, IFN-γ, TGFβ1, TNF-α) were analysed using commercially available kits. Besides, inhibitory effect of dexamethasone on proliferative response of PHA-stimulated peripheral blood lymphocytes had been assessed. Results Bcc infected patients did not differ from Bcc free ones in demographic and clinical parameters, but demonstrated an increased rate of glucose metabolism disturbances and survival disadvantage during prolong follow-up period. Biomarkers analyses revealed elevated TNF-α and reduced IL-17F levels in sputum samples of Bcc infected patients. These patients also demonstrated improvement of peripheral blood lymphocyte sensitivity to steroid treatment and reduction in plasma pro-inflammatory (IL-17F and IL-18) and anti-inflammatory (TGFβ1 and IL-10) cytokine concentrations. Conclusions Reduction in IL-17F levels may have several important consequences including increase in steroid sensitivity and glycemic control disturbances. Further investigations are needed to clarify the role of IL-17 cytokines in CF complication development. Low plasma TGFβ1 and IL-10 levels in Bcc infected group may be a sign of subverted activity of regulatory T cells. Such immune alterations may be one of the factors contributing to the development of the cepacia syndrome.
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Affiliation(s)
- Galina Shmarina
- Research Centre for Medical Genetics, Moscow, Russia
- Peoples' Friendship University of Russia (RUDN University), Moscow, Russia
| | | | - Vassiliy Shmarin
- Research Centre for Medical Genetics, Moscow, Russia
- First Moscow State Medical University, Moscow, Russia
| | - Sergey Semykin
- Russian Clinical Children's Hospital, a separate structural unit of the Russian National Research Medical University, Moscow, Russia
| | - Lusine Avakyan
- Russian Clinical Children's Hospital, a separate structural unit of the Russian National Research Medical University, Moscow, Russia
| | | | - Anastasia Goryainova
- Russian Clinical Children's Hospital, a separate structural unit of the Russian National Research Medical University, Moscow, Russia
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Kim SY, Kim MH, Son JH, Kim SI, Yun SH, Kim K, Kim S, Shin M, Lee JC. Outer membrane vesicles produced by Burkholderia cepacia cultured with subinhibitory concentrations of ceftazidime enhance pro-inflammatory responses. Virulence 2021; 11:995-1005. [PMID: 32799627 PMCID: PMC7567438 DOI: 10.1080/21505594.2020.1802193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BURKHOLDERIA CEPACIA is an opportunistic pathogen that infects patients with debilitating underlying diseases. This study investigated the production of outer membrane vesicles (OMVs) by B. cepacia cultured with sub-minimum inhibitory concentrations (MICs) of antibiotics and examined their pathogenic roles both in vitro and in vivo. B. cepacia ATCC 25416 produced more OMVs under antibiotic stress conditions than controls. OMVs isolated from B. cepacia cultured in Luria-Bertani (LB) broth (OMVs/LB) induced cytotoxicity and the expression of pro-inflammatory cytokine genes in A549 cells in a dose-dependent manner. Host cell cytotoxicity and pro-inflammatory responses were significantly higher in A549 cells treated with B. cepacia OMVs cultured with 1/4 MIC of ceftazidime (OMVs/CAZ) than in the cells treated with OMVs/LB, OMVs cultured with 1/4 MIC of trimethoprim/sulfamethoxazole (OMVs/SXT), or OMVs cultured with 1/4 MIC of meropenem. Intratracheal injection of B. cepacia OMVs also induced histopathology in vivo in mouse lungs. Expressions of IL-1β and TNF-α genes were significantly up-regulatedin the lungs of mice treated with OMVs/CAZ compared to mice administered other OMVs; the expression of the GRO-α gene, however, was significantly up-regulated in OMVs/SXT. In conclusion, OMVs produced by B. cepacia under different antibiotic stress conditions induce different host responses that may contribute to the pathogenesis of B. cepacia.
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Affiliation(s)
- Se Yeon Kim
- Department of Microbiology, School of Medicine, Kyungpook National University , Daegu, Republic of Korea
| | - Mi Hyun Kim
- Department of Microbiology, School of Medicine, Kyungpook National University , Daegu, Republic of Korea
| | - Joo Hee Son
- Department of Microbiology, School of Medicine, Kyungpook National University , Daegu, Republic of Korea
| | - Seung Il Kim
- Drug & Disease Target Team, Korea Basic Science Institute , Ochang, Republic of Korea.,Department of Bio-Analytical Science, University of Science and Technology (UST) , Daejeon, Republic of Korea
| | - Sung Ho Yun
- Drug & Disease Target Team, Korea Basic Science Institute , Ochang, Republic of Korea
| | - Kyeongmin Kim
- Department of Microbiology, School of Medicine, Kyungpook National University , Daegu, Republic of Korea
| | - Shukho Kim
- Department of Microbiology, School of Medicine, Kyungpook National University , Daegu, Republic of Korea
| | - Minsang Shin
- Department of Microbiology, School of Medicine, Kyungpook National University , Daegu, Republic of Korea
| | - Je Chul Lee
- Department of Microbiology, School of Medicine, Kyungpook National University , Daegu, Republic of Korea
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Lauman P, Dennis JJ. Advances in Phage Therapy: Targeting the Burkholderia cepacia Complex. Viruses 2021; 13:1331. [PMID: 34372537 PMCID: PMC8310193 DOI: 10.3390/v13071331] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/29/2021] [Accepted: 07/06/2021] [Indexed: 01/16/2023] Open
Abstract
The increasing prevalence and worldwide distribution of multidrug-resistant bacterial pathogens is an imminent danger to public health and threatens virtually all aspects of modern medicine. Particularly concerning, yet insufficiently addressed, are the members of the Burkholderia cepacia complex (Bcc), a group of at least twenty opportunistic, hospital-transmitted, and notoriously drug-resistant species, which infect and cause morbidity in patients who are immunocompromised and those afflicted with chronic illnesses, including cystic fibrosis (CF) and chronic granulomatous disease (CGD). One potential solution to the antimicrobial resistance crisis is phage therapy-the use of phages for the treatment of bacterial infections. Although phage therapy has a long and somewhat checkered history, an impressive volume of modern research has been amassed in the past decades to show that when applied through specific, scientifically supported treatment strategies, phage therapy is highly efficacious and is a promising avenue against drug-resistant and difficult-to-treat pathogens, such as the Bcc. In this review, we discuss the clinical significance of the Bcc, the advantages of phage therapy, and the theoretical and clinical advancements made in phage therapy in general over the past decades, and apply these concepts specifically to the nascent, but growing and rapidly developing, field of Bcc phage therapy.
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Affiliation(s)
| | - Jonathan J. Dennis
- Department of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, Canada;
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Ganesh PS, Vishnupriya S, Vadivelu J, Mariappan V, Vellasamy KM, Shankar EM. Intracellular survival and innate immune evasion of Burkholderia cepacia: Improved understanding of quorum sensing-controlled virulence factors, biofilm, and inhibitors. Microbiol Immunol 2020; 64:87-98. [PMID: 31769530 DOI: 10.1111/1348-0421.12762] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 11/18/2019] [Accepted: 11/21/2019] [Indexed: 12/25/2022]
Abstract
Burkholderia cepacia complex (Bcc) are opportunistic pathogens implicated with nosocomial infections, and high rates of morbidity and mortality, especially in individuals with cystic fibrosis (CF). B. cepacia are naturally resistant to different classes of antibiotics, and can subvert the host innate immune responses by producing quorum sensing (QS) controlled virulence factors and biofilms. It still remains a conundrum as to how exactly the bacterium survives the intracellular environment within the host cells of CF patients and immunocompromised individuals although the bacterium can invade human lung epithelial cells, neutrophils, and murine macrophages. The mechanisms associated with intracellular survival in the airway epithelial cells and the role of QS and virulence factors in B. cepacia infections in cystic fibrosis remain largely unclear. The current review focuses on understanding the role of QS-controlled virulence factors and biofilms, and provides additional impetus to understanding the potentials of QS-inhibitory strategies against B. cepacia.
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Affiliation(s)
- Pitchaipillai Sankar Ganesh
- Division of Infection Biology & Medical Microbiology, Department of Life Sciences, School of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India
| | - Sivakumar Vishnupriya
- Division of Infection Biology & Medical Microbiology, Department of Life Sciences, School of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India
| | - Jamuna Vadivelu
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Vanitha Mariappan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kumutha M Vellasamy
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Esaki M Shankar
- Division of Infection Biology & Medical Microbiology, Department of Life Sciences, School of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India
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Sattar AA, Abate W, Fejer G, Bradley G, Jackson SK. Evaluation of the proinflammatory effects of contaminated bathing water. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2019; 82:1076-1087. [PMID: 31797748 DOI: 10.1080/15287394.2019.1694113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Contaminated marine bathing water has been reported to adversely affect human health. Our data demonstrated a correlation between total endotoxin (lipopolysaccharide; LPS) levels and degree of contamination of marine bathing waters. To assess the potential health implications of LPS present in marine bathing waters, the inflammation-inducing potency of water samples collected at different time points at multiple sampling sites were assessed using a cell culture-based assay. The numbers of fecal indicator bacteria (FIB) were also examined in the same samples. Water samples were used to stimulate two cell culture models: (1) a novel non-transformed continuously growing murine cell line Max Plank Institute (MPI) characteristic of alveolar macrophages and (2) human MonoMac 6 monocyte cell line. The inflammatory potential of the samples was assessed by measuring the release of inflammatory cytokines. The presence of high levels of LPS in contaminated bathing water led to induction of inflammatory response from our in vitro cell-based bioassays suggesting its potential health impact. This finding introduces an in vitro culture assay that reflects the level of LPS in water samples. These observations further promote previous finding that LPS is a reliable surrogate biomarker for fecal contamination of bathing water.
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Affiliation(s)
- Anas A Sattar
- School of Biomedical and Healthcare Science, Plymouth University, Plymouth, UK
| | - Wondwossen Abate
- School of Biomedical and Healthcare Science, Plymouth University, Plymouth, UK
| | - Gyorgy Fejer
- School of Biomedical and Healthcare Science, Plymouth University, Plymouth, UK
| | - Graham Bradley
- School of Biomedical and Healthcare Science, Plymouth University, Plymouth, UK
| | - Simon K Jackson
- School of Biomedical and Healthcare Science, Plymouth University, Plymouth, UK
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Yun HK, Park J, Chae U, Lee HS, Huh JW, Lee SR, Bae YC, Lee DS. Parkin in early stage LPS-stimulated BV-2 cells regulates pro-inflammatory response and mitochondrial quality via mitophagy. J Neuroimmunol 2019; 336:577044. [DOI: 10.1016/j.jneuroim.2019.577044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 08/27/2019] [Accepted: 08/27/2019] [Indexed: 12/29/2022]
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Zhang Y, Meng J, Zhang L, Ramkrishnan S, Roy S. Extracellular Vesicles with Exosome-like Features Transfer TLRs between Dendritic Cells. Immunohorizons 2019; 3:186-193. [PMID: 31356164 DOI: 10.4049/immunohorizons.1900016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 05/13/2019] [Indexed: 12/19/2022] Open
Abstract
Accumulating evidence shows that extracellular vesicles (EVs) secreted by immune cells play an important role in intercellular communication. In the current report, we show that EVs released from wild-type bone marrow-derived dendritic cells (BMDCs) transfer TLRs to TLR4-knockout (TLR4KO) BMDCs and increase cellular responsiveness to LPS in recipient cells. The transferred EVs have exosomal characteristics and induce the activation of NF-κB signaling pathways in recipient cells. We further show that BMDC-derived EVs can promote LPS-induced inflammation in TLR4KO mice in vivo. These results indicate that functional TLR4 can be transferred from wild-type to TLR4KO BMDCs through exosome-like EVs.
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Affiliation(s)
- Yue Zhang
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33101; and
| | - Jingjing Meng
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33101; and
| | - Li Zhang
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33101; and.,Department of Pharmacology, University of Minnesota, Minneapolis, MN 55455
| | - Sundaram Ramkrishnan
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33101; and
| | - Sabita Roy
- Department of Surgery, Miller School of Medicine, University of Miami, Miami, FL 33101; and
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Hu Y, Li B, Wen L, He K. Study on the anti-endotoxin effect of sinomenine using an Agilent genome array. QJM 2018; 111:171-178. [PMID: 29240916 DOI: 10.1093/qjmed/hcx234] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Endotoxin is a significant contributing factor underlying the occurrence of fever, diarrhea, inflammation, edema, coagulation, shock and other syndromes associated with gram-negative bacterial infections. To date, there is no effective treatment for endotoxemia. AIM The aim of this study was to characterize differentially expressed genes in sinomenine-treated and lipopolysaccharide (LPS)-induced endothelial cells by microarray analysis and to determine the potential pharmacological activity of sinomenine. DESIGN The cultured cells of five treatment groups (n = 3) were collected. Participants: total RNA was extracted and subjected to Agilent Porcine 4 × 44 K whole genome microarray. METHODS Kyoto encyclopedia of genes and genomes and gene ontology software were applied to screen and analyze differentially regulated genes. RESULTS The results showed that 723 differentially regulated genes were identified including 410 up-regulated genes and 313 down-regulated genes in therapy group vs. LPS group. Ten genes may be key controlled genes in the pathogenesis of LPS, including five up-regulated genes (ARG1, TLR2, IL1A, VCAM1, DKK3) and five down-regulated genes (HABP2, ID1, CHDH, GPX3, PTGFR), which primarily contribute to biological processes such as inflammatory response, vascular lesion, metabolic process and cell cycle. IL1A and FMO3 were considered as potent target genes. CONCLUSION Global gene expression profile analysis showed that sinomenine might effectively be useful to regulate inflammatory responses as part of future anti-endotoxin therapies.
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Affiliation(s)
- Y Hu
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - B Li
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - L Wen
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - K He
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
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Roux D, Schaefers M, Clark BS, Weatherholt M, Renaud D, Scott D, LiPuma JJ, Priebe G, Gerard C, Yoder-Himes DR. A putative lateral flagella of the cystic fibrosis pathogen Burkholderia dolosa regulates swimming motility and host cytokine production. PLoS One 2018; 13:e0189810. [PMID: 29346379 PMCID: PMC5773237 DOI: 10.1371/journal.pone.0189810] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 12/01/2017] [Indexed: 01/25/2023] Open
Abstract
Burkholderia dolosa caused an outbreak in the cystic fibrosis clinic at Boston Children's Hospital and was associated with high mortality in these patients. This species is part of a larger complex of opportunistic pathogens known as the Burkholderia cepacia complex (Bcc). Compared to other species in the Bcc, B. dolosa is highly transmissible; thus understanding its virulence mechanisms is important for preventing future outbreaks. The genome of one of the outbreak strains, AU0158, revealed a homolog of the lafA gene encoding a putative lateral flagellin, which, in other non-Bcc species, is used for movement on solid surfaces, attachment to host cells, or movement inside host cells. Here, we analyzed the conservation of the lafA gene and protein sequences, which are distinct from those of the polar flagella, and found lafA homologs to be present in numerous β-proteobacteria but notably absent from most other Bcc species. A lafA deletion mutant in B. dolosa showed a greater swimming motility than wild-type due to an increase in the number of polar flagella, but did not appear to contribute to biofilm formation, host cell invasion, or murine lung colonization or persistence over time. However, the lafA gene was important for cytokine production in human peripheral blood mononuclear cells, suggesting it may have a role in recognition by the human immune response.
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Affiliation(s)
- Damien Roux
- INSERM, IAME, UMR 1137, Paris, France
- Univ Paris Diderot, Sorbonne Paris Cité, Paris, France
- AP-HP, Louis Mourier Hospital, Intensive Care Unit, Colombes, France
| | - Matthew Schaefers
- Division of Critical Care Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Anesthesia, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Bradley S. Clark
- Department of Biology, University of Louisville, Louisville, Kentucky, United States of America
| | - Molly Weatherholt
- Department of Biology, University of Louisville, Louisville, Kentucky, United States of America
| | - Diane Renaud
- Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, Kentucky, United States of America
| | - David Scott
- Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, Kentucky, United States of America
| | - John J. LiPuma
- Division of Pediatrics, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Gregory Priebe
- Division of Critical Care Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Department of Anesthesia, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Craig Gerard
- Division of Respiratory Diseases, Boston Children’s Hospital, Boston, Massachusetts, United States of America
| | - Deborah R. Yoder-Himes
- Department of Biology, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail:
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Ma L, Yang Y, Sun X, Jiang M, Ma Y, Yang X, Guo Z. Propofol regulates the expression of TLR4 through miR‑21 in human umbilical vein endothelial cells. Mol Med Rep 2017; 16:9074-9080. [PMID: 29039542 DOI: 10.3892/mmr.2017.7765] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 07/13/2017] [Indexed: 11/05/2022] Open
Abstract
Propofol (2,6-diisopropylphenol) is one of the most commonly used intravenous anesthetics. Anesthetics can regulate the inflammatory process; however, the mechanism remains to be fully elucidated. The present study aimed to investigate whether and how propofol affects the inflammatory reaction in human umbilical vein endothelial cells (HUVECs). The expression levels of Toll‑like receptor 4 (TLR4) and cluster of differentiation 14 (CD14) were determined in HUVECs treated with propofol and lipopolysaccharide (LPS) using western blot and reverse transcription‑quantitative polymerase chain reaction analyses. In addition, whether propofol regulated the expression of TLR4 though microRNA (miR)‑21 was examined. The results showed that LPS promoted the expression levels of TLR4, CD14 and tumor necrosis factor α (TNFα), and suppressed the expression of miR‑21 in HUVECs. Propofol suppressed the expression levels of TLR4, CD14 and TNFα, and upregulated the expression of miR‑21 in a concentration‑dependent manner. miR‑21 downregulated the expression of TLR4 at the mRNA and protein levels, whereas the miR‑21 mimic reversed the effect of LPS on the expression of TLR4. In addition, the miR‑21 inhibitor inhibited the downregulatory effect of propofol on the expression of TLR4. TargetScan analysis showed that TLR4 was included in the list of targets of miR‑21. Fluorescent reporter assays showed that the miR‑21 mimic and propofol treatment reduced the fluorescence intensity in cells transfected with a reporter vector containing the wild‑type TLR4 3'‑untranslated region. Taken together, the results of the present study demonstrated that propofol regulated the expression of TLR4 in HUVECs through miR‑21.
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Affiliation(s)
- Ling Ma
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Yue Yang
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Xuechen Sun
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Meiling Jiang
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Yang Ma
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Xilun Yang
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
| | - Zhiwei Guo
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, Liaoning 110004, P.R. China
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Abate W, Sattar AA, Liu J, Conway ME, Jackson SK. Evaluation of recombinant factor C assay for the detection of divergent lipopolysaccharide structural species and comparison with Limulus amebocyte lysate-based assays and a human monocyte activity assay. J Med Microbiol 2017; 66:888-897. [DOI: 10.1099/jmm.0.000510] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Wondwossen Abate
- Centre for Biomedical Research, School of Biomedical and Healthcare Sciences, Peninsula Schools of Medicine and Dentistry, Plymouth University, Plymouth, UK
| | - Anas A. Sattar
- Centre for Biomedical Research, School of Biomedical and Healthcare Sciences, Peninsula Schools of Medicine and Dentistry, Plymouth University, Plymouth, UK
| | - Jian Liu
- Academic Unit of Ophthalmology, University of Bristol, Bristol, UK
| | - Myra E. Conway
- Centre for Research in Biosciences, Faculty of Health and Life Sciences, University of the West of England, Bristol, UK
| | - Simon K. Jackson
- Centre for Biomedical Research, School of Biomedical and Healthcare Sciences, Peninsula Schools of Medicine and Dentistry, Plymouth University, Plymouth, UK
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He M, Ichinose T, Yoshida S, Ito T, He C, Yoshida Y, Arashidani K, Takano H, Sun G, Shibamoto T. PM2.5-induced lung inflammation in mice: Differences of inflammatory response in macrophages and type II alveolar cells. J Appl Toxicol 2017; 37:1203-1218. [DOI: 10.1002/jat.3482] [Citation(s) in RCA: 101] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/13/2017] [Accepted: 03/30/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Miao He
- Department of Environmental Health, School of Public Health; China Medical University; Shenyang 110122 China
- Department of Health Sciences; Oita University of Nursing and Health Sciences; Oita 870-1201 Japan
| | - Takamichi Ichinose
- Department of Health Sciences; Oita University of Nursing and Health Sciences; Oita 870-1201 Japan
| | - Seiichi Yoshida
- Department of Health Sciences; Oita University of Nursing and Health Sciences; Oita 870-1201 Japan
| | - Tomohiro Ito
- Center for Health and Environmental Risk Research; National Institute for Environmental Studies; 16-2 Onogawa, Tsukuba Ibaraki 305-8506 Japan
| | - Cuiying He
- Department of Immunology and Parasitology, School of Medicine; University of Occupational and Environmental Health; Fukuoka 807-8555 Japan
| | - Yasuhiro Yoshida
- Department of Immunology and Parasitology, School of Medicine; University of Occupational and Environmental Health; Fukuoka 807-8555 Japan
| | - Keiichi Arashidani
- Department of Immunology and Parasitology, School of Medicine; University of Occupational and Environmental Health; Fukuoka 807-8555 Japan
| | - Hirohisa Takano
- Environmental Health Division, Department of Environmental Engineering, Graduate School of Engineering; Kyoto University; Kyoto 615-8530 Japan
| | - Guifan Sun
- Department of Environmental Health, School of Public Health; China Medical University; Shenyang 110122 China
| | - Takayuki Shibamoto
- Department of Environmental Toxicology; University of California; Davis CA 95616 USA
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Immune Recognition of the Epidemic Cystic Fibrosis Pathogen Burkholderia dolosa. Infect Immun 2017; 85:IAI.00765-16. [PMID: 28348057 DOI: 10.1128/iai.00765-16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 03/20/2017] [Indexed: 12/31/2022] Open
Abstract
Burkholderia dolosa caused an outbreak in the cystic fibrosis (CF) clinic at Boston Children's Hospital from 1998 to 2005 and led to the infection of over 40 patients, many of whom died due to complications from infection by this organism. To assess whether B. dolosa significantly contributes to disease or is recognized by the host immune response, mice were infected with a sequenced outbreak B. dolosa strain, AU0158, and responses were compared to those to the well-studied CF pathogen Pseudomonas aeruginosa In parallel, mice were also infected with a polar flagellin mutant of B. dolosa to examine the role of flagella in B. dolosa lung colonization. The results showed a higher persistence in the host by B. dolosa strains, and yet, neutrophil recruitment and cytokine production were lower than those with P. aeruginosa The ability of host immune cells to recognize B. dolosa was then assessed, B. dolosa induced a robust cytokine response in cultured cells, and this effect was dependent on the flagella only when bacteria were dead. Together, these results suggest that B. dolosa can be recognized by host cells in vitro but may avoid or suppress the host immune response in vivo through unknown mechanisms. B. dolosa was then compared to other Burkholderia species and found to induce similar levels of cytokine production despite being internalized by macrophages more than Burkholderia cenocepacia strains. These data suggest that B. dolosa AU0158 may act differently with host cells and is recognized differently by immune systems than are other Burkholderia strains or species.
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Fathy Mohamed Y, Hamad M, Ortega XP, Valvano MA. The LpxL acyltransferase is required for normal growth and penta-acylation of lipid A in Burkholderia cenocepacia. Mol Microbiol 2017; 104:144-162. [PMID: 28085228 DOI: 10.1111/mmi.13618] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/10/2017] [Indexed: 12/27/2022]
Abstract
Lipid A anchors the lipopolysaccharide (LPS) to the outer membrane and is usually composed of a hexa-acylated diglucosamine backbone. Burkholderia cenocepacia, an opportunistic pathogen, produces a mixture of tetra- and penta-acylated lipid A. "Late" acyltransferases add secondary acyl chains to lipid A after the incorporation of four primary acyl chains to the diglucosamine backbone. Here, we report that B. cenocepacia has only one late acyltransferase, LpxL (BCAL0508), which adds a myristoyl chain to the 2' position of lipid A resulting in penta-acylated lipid A. We also identified PagL (BCAL0788), which acts as an outer membrane lipase by removing the primary β-hydroxymyristate (3-OH-C14:0) chain at the 3 position, leading to tetra-acylated lipid A. Unlike PagL, LpxL depletion caused reduced cell growth and defects in cell morphology, both of which were suppressed by overexpressing the LPS flippase MsbA (BCAL2408), suggesting that lipid A molecules lacking the fifth acyl chain contributed by LpxL are not good substrates for the flippase. We also show that intracellular B. cenocepacia within macrophages produced more penta-acylated lipid A, suggesting lipid A penta-acylation in B. cenocepacia is required not only for bacterial growth and morphology but also for adaptation to intracellular lifestyle.
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Affiliation(s)
- Yasmine Fathy Mohamed
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, BT9 7BL, UK.,Department of Microbiology and Immunology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mohamad Hamad
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada, N6A 5C1
| | - Ximena P Ortega
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada, N6A 5C1
| | - Miguel A Valvano
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, BT9 7BL, UK.,Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada, N6A 5C1
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15
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Miller AH, Vayttaden SJ, Al-Khodor S, Fraser IDC. Assay Development for Image-Based Quantification of Intracellular Bacterial Replication and Analysis of the Innate Immune Response to Infection. Assay Drug Dev Technol 2015; 13:515-28. [PMID: 26505731 DOI: 10.1089/adt.2015.664] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Severe bacterial infection can lead to inflammation, host tissue damage, and ultimately disseminated septic shock. The mammalian innate immune system responds to microbial infection through the detection of invariant pathogen-associated molecular patterns (PAMPs) by a range of pattern recognition receptors (PRRs) expressed by the host cell. A successful immune response involves tightly coordinated signaling from these receptors, leading to a robust transcriptional response producing cytokines and antimicrobial effectors. While the PRR-expressing phagocytes of the host innate immune system function to contain and degrade internalized bacteria through pathways such as selective autophagy, pathogenic bacteria may subvert this process to replicate in the host cell. We describe the development of imaging assays to investigate these host-pathogen interactions through gene perturbation screens, which could lead to the identification of novel effectors of the host response to bacterial infection. We identify markers of coordinated initial signaling in macrophages challenged with ligands to PRRs of the toll-like receptor (TLR) family and compare this response to that induced by intact bacteria of the Burkholderia cenocepacia complex (Bcc), an opportunistic pathogen that causes life-threatening infections in patients with cystic fibrosis and chronic granulomatous disease. Bcc has been shown to escape the endocytic pathway, activate selective autophagy, and replicate within human macrophages. We demonstrate robust image-based quantification of multiple stages of Bcc infection of macrophages: ubiquitin tagging of cytosolic bacteria, recruitment of selective autophagy effector proteins, and intracellular bacterial replication, and we show perturbation of bacterial replication using drug treatment or siRNA-based gene knockdown. The described panel of imaging assays can be extended to other bacterial infections and pathogenic ligand combinations where high-content siRNA screening could provide significant new insight into regulation of the innate immune response to infection.
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Affiliation(s)
- Alexandra H Miller
- 1 Signaling Systems Unit, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland
| | - Sharat J Vayttaden
- 1 Signaling Systems Unit, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland
| | - Souhaila Al-Khodor
- 2 Infectious Disease Unit, Division of Translational Medicine, Sidra Medical and Research Center , Doha, Qatar
| | - Iain D C Fraser
- 1 Signaling Systems Unit, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health , Bethesda, Maryland
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16
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Di Lorenzo F, Kubik Ł, Oblak A, Lorè NI, Cigana C, Lanzetta R, Parrilli M, Hamad MA, De Soyza A, Silipo A, Jerala R, Bragonzi A, Valvano MA, Martín-Santamaría S, Molinaro A. Activation of Human Toll-like Receptor 4 (TLR4)·Myeloid Differentiation Factor 2 (MD-2) by Hypoacylated Lipopolysaccharide from a Clinical Isolate of Burkholderia cenocepacia. J Biol Chem 2015; 290:21305-19. [PMID: 26160169 DOI: 10.1074/jbc.m115.649087] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Indexed: 11/06/2022] Open
Abstract
Lung infection by Burkholderia species, in particular Burkholderia cenocepacia, accelerates tissue damage and increases post-lung transplant mortality in cystic fibrosis patients. Host-microbe interplay largely depends on interactions between pathogen-specific molecules and innate immune receptors such as Toll-like receptor 4 (TLR4), which recognizes the lipid A moiety of the bacterial lipopolysaccharide (LPS). The human TLR4·myeloid differentiation factor 2 (MD-2) LPS receptor complex is strongly activated by hexa-acylated lipid A and poorly activated by underacylated lipid A. Here, we report that B. cenocepacia LPS strongly activates human TLR4·MD-2 despite its lipid A having only five acyl chains. Furthermore, we show that aminoarabinose residues in lipid A contribute to TLR4-lipid A interactions, and experiments in a mouse model of LPS-induced endotoxic shock confirmed the proinflammatory potential of B. cenocepacia penta-acylated lipid A. Molecular modeling combined with mutagenesis of TLR4-MD-2 interactive surfaces suggests that longer acyl chains and the aminoarabinose residues in the B. cenocepacia lipid A allow exposure of the fifth acyl chain on the surface of MD-2 enabling interactions with TLR4 and its dimerization. Our results provide a molecular model for activation of the human TLR4·MD-2 complex by penta-acylated lipid A explaining the ability of hypoacylated B. cenocepacia LPS to promote proinflammatory responses associated with the severe pathogenicity of this opportunistic bacterium.
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Affiliation(s)
- Flaviana Di Lorenzo
- From the Departments of Chemical Sciences and Department of Biotechnology, National Institute of Chemistry, Ljubljana 1000, Slovenia
| | - Łukasz Kubik
- Department of Chemistry and Biochemistry, Universidad CEU San Pablo, Boadilla del Monte, Madrid 28668, Spain, Department of Biopharmaceutics and Pharmacodynamics, Medical University of Gdańsk, Gdańsk 80-416, Poland
| | - Alja Oblak
- Department of Biotechnology, National Institute of Chemistry, Ljubljana 1000, Slovenia, Centre of Excellence NMR - Future Innovation for Sustainable Technologies, Ljubljana 1000, Slovenia
| | - Nicola Ivan Lorè
- Infection and Cystic Fibrosis Unit, Istituto di Ricovero e Cura a Carattere Scientifico-San Raffaele Scientific Institute, Milan 20132, Italy
| | - Cristina Cigana
- Infection and Cystic Fibrosis Unit, Istituto di Ricovero e Cura a Carattere Scientifico-San Raffaele Scientific Institute, Milan 20132, Italy
| | | | | | - Mohamad A Hamad
- Department of Microbiology and Immunology, University of Western Ontario, London N6A 5C1, Canada
| | - Anthony De Soyza
- Applied Immunobiology and Transplantation Group, Institute of Cellular Medicine, University of Newcastle, Newcastle NE1 7RU, United Kingdom, and
| | - Alba Silipo
- From the Departments of Chemical Sciences and
| | - Roman Jerala
- Department of Biotechnology, National Institute of Chemistry, Ljubljana 1000, Slovenia, Centre of Excellence NMR - Future Innovation for Sustainable Technologies, Ljubljana 1000, Slovenia
| | - Alessandra Bragonzi
- Infection and Cystic Fibrosis Unit, Istituto di Ricovero e Cura a Carattere Scientifico-San Raffaele Scientific Institute, Milan 20132, Italy
| | - Miguel A Valvano
- Department of Microbiology and Immunology, University of Western Ontario, London N6A 5C1, Canada, Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 7AE, United Kingdom
| | - Sonsoles Martín-Santamaría
- Department of Chemistry and Biochemistry, Universidad CEU San Pablo, Boadilla del Monte, Madrid 28668, Spain,
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17
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Costello A, Reen FJ, O'Gara F, Callaghan M, McClean S. Inhibition of co-colonizing cystic fibrosis-associated pathogens by Pseudomonas aeruginosa and Burkholderia multivorans. MICROBIOLOGY-SGM 2014; 160:1474-1487. [PMID: 24790091 DOI: 10.1099/mic.0.074203-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cystic fibrosis (CF) is a recessive genetic disease characterized by chronic respiratory infections and inflammation causing permanent lung damage. Recurrent infections are caused by Gram-negative antibiotic-resistant bacterial pathogens such as Pseudomonas aeruginosa, Burkholderia cepacia complex (Bcc) and the emerging pathogen genus Pandoraea. In this study, the interactions between co-colonizing CF pathogens were investigated. Both Pandoraea and Bcc elicited potent pro-inflammatory responses that were significantly greater than Ps. aeruginosa. The original aim was to examine whether combinations of pro-inflammatory pathogens would further exacerbate inflammation. In contrast, when these pathogens were colonized in the presence of Ps. aeruginosa the pro-inflammatory response was significantly decreased. Real-time PCR quantification of bacterial DNA from mixed cultures indicated that Ps. aeruginosa significantly inhibited the growth of Burkholderia multivorans, Burkholderia cenocepacia, Pandoraea pulmonicola and Pandoraea apista, which may be a factor in its dominance as a colonizer of CF patients. Ps. aeruginosa cell-free supernatant also suppressed growth of these pathogens, indicating that inhibition was innate rather than a response to the presence of a competitor. Screening of a Ps. aeruginosa mutant library highlighted a role for quorum sensing and pyoverdine biosynthesis genes in the inhibition of B. cenocepacia. Pyoverdine was confirmed to contribute to the inhibition of B. cenocepacia strain J2315. B. multivorans was the only species that could significantly inhibit Ps. aeruginosa growth. B. multivorans also inhibited B. cenocepacia and Pa. apista. In conclusion, both Ps. aeruginosa and B. multivorans are capable of suppressing growth and virulence of co-colonizing CF pathogens.
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Affiliation(s)
- Anne Costello
- Centre of Microbial Host Interactions, Centre of Applied Science for Health, Institute of Technology Tallaght, Old Blessington Road, Tallaght, Dublin 24, Ireland
| | - F Jerry Reen
- BIOMERIT Research Centre, Department of Microbiology, University College Cork, Ireland
| | - Fergal O'Gara
- Curtin University, School of Biomedical Sciences, Perth, WA 6845, Australia.,BIOMERIT Research Centre, Department of Microbiology, University College Cork, Ireland
| | - Máire Callaghan
- Centre of Microbial Host Interactions, Centre of Applied Science for Health, Institute of Technology Tallaght, Old Blessington Road, Tallaght, Dublin 24, Ireland
| | - Siobhán McClean
- Centre of Microbial Host Interactions, Centre of Applied Science for Health, Institute of Technology Tallaght, Old Blessington Road, Tallaght, Dublin 24, Ireland
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18
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Marchetti R, Canales A, Lanzetta R, Nilsson I, Vogel C, Reed DE, AuCoin DP, Jiménez-Barbero J, Molinaro A, Silipo A. Unraveling the Interaction between the LPS O-Antigen ofBurkholderia anthinaand the 5D8 Monoclonal Antibody by Using a Multidisciplinary Chemical Approach, with Synthesis, NMR, and Molecular Modeling Methods. Chembiochem 2013; 14:1485-93. [DOI: 10.1002/cbic.201300225] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Indexed: 11/11/2022]
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19
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Kabanov DS, Prokhorenko IR. Involvement of Toll-like receptor 4 and Fc receptors gamma in human neutrophil priming by endotoxins from Escherichia coli. BIOCHEMISTRY (MOSCOW) 2013; 78:185-93. [DOI: 10.1134/s0006297913020077] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Gavrilin MA, Abdelaziz DHA, Mostafa M, Abdulrahman BA, Grandhi J, Akhter A, Abu Khweek A, Aubert DF, Valvano MA, Wewers MD, Amer AO. Activation of the pyrin inflammasome by intracellular Burkholderia cenocepacia. THE JOURNAL OF IMMUNOLOGY 2012; 188:3469-77. [PMID: 22368275 DOI: 10.4049/jimmunol.1102272] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Burkholderia cenocepacia is an opportunistic pathogen that causes chronic infection and induces progressive respiratory inflammation in cystic fibrosis patients. Recognition of bacteria by mononuclear cells generally results in the activation of caspase-1 and processing of IL-1β, a major proinflammatory cytokine. In this study, we report that human pyrin is required to detect intracellular B. cenocepacia leading to IL-1β processing and release. This inflammatory response involves the host adapter molecule ASC and the bacterial type VI secretion system (T6SS). Human monocytes and THP-1 cells stably expressing either small interfering RNA against pyrin or YFP-pyrin and ASC (YFP-ASC) were infected with B. cenocepacia and analyzed for inflammasome activation. B. cenocepacia efficiently activates the inflammasome and IL-1β release in monocytes and THP-1. Suppression of pyrin levels in monocytes and THP-1 cells reduced caspase-1 activation and IL-1β release in response to B. cenocepacia challenge. In contrast, overexpression of pyrin or ASC induced a robust IL-1β response to B. cenocepacia, which correlated with enhanced host cell death. Inflammasome activation was significantly reduced in cells infected with T6SS-defective mutants of B. cenocepacia, suggesting that the inflammatory reaction is likely induced by an as yet uncharacterized effector(s) of the T6SS. Together, we show for the first time, to our knowledge, that in human mononuclear cells infected with B. cenocepacia, pyrin associates with caspase-1 and ASC forming an inflammasome that upregulates mononuclear cell IL-1β processing and release.
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Affiliation(s)
- Mikhail A Gavrilin
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Internal Medicine, The Ohio State University, Columbus, OH 43210, USA.
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21
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Ganesan S, Sajjan US. Host evasion by Burkholderia cenocepacia. Front Cell Infect Microbiol 2012; 1:25. [PMID: 22919590 PMCID: PMC3417383 DOI: 10.3389/fcimb.2011.00025] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Accepted: 12/22/2011] [Indexed: 11/13/2022] Open
Abstract
Burkholderia cenocepacia is an opportunistic respiratory pathogen of individuals with cystic fibrosis (CF). Some strains of B. cenocepacia are highly transmissible and resistant to almost all antibiotics. Approximately one-third of B. cenocepacia infected CF patients go on to develop fatal "cepacia syndrome." During the last two decades, substantial progress has been made with regards to evasion of host innate defense mechanisms by B. cenocepacia. Almost all strains of B. cenocepacia have the capacity to survive and replicate intracellularly in both airway epithelial cells and macrophages, which are primary sentinels of the lung and play a pivotal role in clearance of infecting bacteria. Those strains of B. cenocepacia, which express both cable pili and the associated 22 kDa adhesin are also capable of transmigrating across airway epithelium and persist in mouse models of infection. In this review, we will discuss how this type of interaction between B. cenocepacia and host may lead to persistence of bacteria as well as lung inflammation in CF patients.
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Affiliation(s)
- Shyamala Ganesan
- Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA
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22
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Liu J, Pankhurst LJ, Deacon LJ, Abate W, Hayes ET, Drew GH, Longhurst PJ, Pollard S, Longhurst J, Tyrrel SF, Jackson SK. Evaluation of inflammatory effects of airborne endotoxin emitted from composting sources. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2011; 30:602-6. [PMID: 21154847 DOI: 10.1002/etc.434] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Revised: 09/05/2010] [Accepted: 10/13/2010] [Indexed: 05/04/2023]
Abstract
Because of the lack of effective methodology, the biological effects of environmental endotoxin have not been assessed. Here we have collected and measured airborne endotoxin at different locations around composting sites. Increased endotoxin concentrations were observed close to composting activities and also at nearby boundary areas. Analysis of proinflammatory effects of the environmental endotoxin on interleukin (IL)-8 and IL-6 release from human D562 pharyngeal epithelial and MM6 monocytic cell cultures showed an association between endotoxin level and cytokine induction. The cytokine-inducing effect of bioaerosol extracts was inhibited by polymyxin B, indicating that endotoxin was the cause of cytokine responses we found. The environmental endotoxin was also more active for stimulating cytokines in airway epithelial cells than commercially purified Escherichia coli endotoxin. Our results suggest that these in vitro inflammatory cell models may contribute to the assessment of health impacts of environmental endotoxin.
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Affiliation(s)
- Jian Liu
- University of the West of England, Bristol, United Kingdom
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23
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McKeon S, McClean S, Callaghan M. Macrophage responses to CF pathogens: JNK MAP kinase signaling by Burkholderia cepacia complex lipopolysaccharide. ACTA ACUST UNITED AC 2011; 60:36-43. [PMID: 20602636 DOI: 10.1111/j.1574-695x.2010.00712.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Chronic bacterial colonization of the airways with opportunistic pathogens is the primary cause of morbidity and mortality in cystic fibrosis (CF) patients. Burkholderia cepacia complex (Bcc) organisms pose a particular challenge in CF lung disease, due in part to their ability to trigger a fulminant pneumonia. This study compares the U937 macrophage response to two Bcc species, B. cenocepacia and Burkholderia multivorans, against Pseudomonas aeruginosa and Staphylococcus aureus. The two Bcc strains demonstrated higher levels of U937 macrophage internalization compared with both P. aeruginosa and S. aureus. Both the Bcc strains also stimulated significantly greater levels of tumor necrosis factor-α and interleukin-1β from macrophages when compared with P. aeruginosa. Further examination of the macrophage response to B. multivorans demonstrated that the lipopolysaccharide component of these bacteria was a potent inducer of proinflammatory cytokines and was shown to signal predominantly through the c-Jun N-terminal kinase mitogen-activated protein kinase pathway. These studies further characterize the host response to Bcc and in particular B. multivorans, now the predominant Bcc species in many CF populations.
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Affiliation(s)
- Suzanne McKeon
- Centre of Microbial Host Interactions, ITT-Dublin, Dublin, Ireland
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24
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Abstract
The Burkholderia cepacia complex (Bcc) is a group of genetically related environmental bacteria that can cause chronic opportunistic infections in patients with cystic fibrosis (CF) and other underlying diseases. These infections are difficult to treat due to the inherent resistance of the bacteria to antibiotics. Bacteria can spread between CF patients through social contact and sometimes cause cepacia syndrome, a fatal pneumonia accompanied by septicemia. Burkholderia cenocepacia has been the focus of attention because initially it was the most common Bcc species isolated from patients with CF in North America and Europe. Today, B. cenocepacia, along with Burkholderia multivorans, is the most prevalent Bcc species in patients with CF. Given the progress that has been made in our understanding of B. cenocepacia over the past decade, we thought that it was an appropriate time to review our knowledge of the pathogenesis of B. cenocepacia, paying particular attention to the characterization of virulence determinants and the new tools that have been developed to study them. A common theme emerging from these studies is that B. cenocepacia establishes chronic infections in immunocompromised patients, which depend more on determinants mediating host niche adaptation than those involved directly in host cells and tissue damage.
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Affiliation(s)
- Slade A. Loutet
- Centre for Human Immunology, Department of Microbiology and Immunology, Department of Medicine, University of Western Ontario, London, Ontario, Canada
| | - Miguel A. Valvano
- Centre for Human Immunology, Department of Microbiology and Immunology, Department of Medicine, University of Western Ontario, London, Ontario, Canada
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25
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Jian Liu, Abate W, Jinsheng Xu, Corry D, Kaul B, Jackson SK. Three-dimensional spheroid cultures of A549 and HepG2 cells exhibit different lipopolysaccharide (LPS) receptor expression and LPS-induced cytokine response compared with monolayer cultures. Innate Immun 2010; 17:245-55. [PMID: 20418262 DOI: 10.1177/1753425910365733] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Lipopolysaccharide (LPS) is a potent modulator of pathogen-induced host inflammatory responses. Lipopolysaccharide signaling to host cells is correlated with the expression of well-characterized LPS receptors. We have developed three-dimensional (3-D) cell cultures (spheroids) that are more representative of in vivo conditions than traditional monolayer cultures and may provide novel in vitro models to study the inflammatory response. In this work, we have compared F-actin organization, LPS-induced pro-inflammatory cytokine response and LPS receptor expression between spheroid and monolayer cultures from A549 lung epithelial cells and HepG2 hepatocytes. Significant junctional F-actin was seen at the cell—cell contact points throughout the spheroids, while monolayer cells showed stress fibers of actin and more prominent F-actin localized at the cell base. A time course of cytokine release in response to LPS showed that A549 spheroids secreted persistently higher levels of interleukin (IL)-6 and IL-8 compared with monolayer cultures. Unlike monolayer cultures, HepG2 spheroids responded to LPS by releasing a significant level of IL-8. We identified a significant increase in the expression of CD14 and MD2 in these spheroids compared with monolayers, which may explain the enhanced cytokine response to LPS. Thus, we suggest that 3-D spheroid cell cultures are more typical of in vivo cell responses to LPS during the development of inflammation and would be a better in vitro model in inflammation studies.
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Affiliation(s)
- Jian Liu
- Centre for Research in Biomedicine, University of the West of England, Bristol UK
| | - Wondwossen Abate
- Centre for Research in Biomedicine, University of the West of England, Bristol UK
| | - Jinsheng Xu
- Centre for Research in Biomedicine, University of the West of England, Bristol UK
| | - David Corry
- Centre for Research in Biomedicine, University of the West of England, Bristol UK
| | - Baksho Kaul
- Centre for Research in Biomedicine, University of the West of England, Bristol UK
| | - Simon K. Jackson
- Centre for Research in Biomedicine, University of the West of England, Bristol UK
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26
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Boucher JG, Parato KA, Frappier F, Fairman P, Busca A, Saxena M, Blahoianu MA, Ma W, Gajanayaka N, Parks RJ, Kumar A, Angel JB. Disparate regulation of LPS-induced MAPK signaling and IL-12p40 expression between different myeloid cell types with and without HIV infection. Viral Immunol 2010; 23:17-28. [PMID: 20121399 DOI: 10.1089/vim.2009.0054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Studies from our laboratory and those of others have implicated lipopolysaccharide (LPS)-induced MAPK signaling as an important pathway in the regulation of cytokine expression. In this article, the regulation of IL-12 expression in two different human myeloid cell populations was evaluated. In primary monocytes, the inhibition of p38 enhanced IL-12 production, whereas it downregulated IL-12 production in THP-1 cells. The role of MAPK signaling in transcription factor binding to the IL-12p40 promoter was subsequently determined. In primary monocytes, ERK and p38 inhibition increased binding of AP-1 and Sp1, respectively, to the IL-12p40 promoter, while JNK inhibition increased NF-kappaB, AP-1, and Sp1 binding. In THP-1 cells, p38, ERK, and JNK inhibition increased NF-kappaB and Sp1 binding to the IL-12p40 promoter, while inhibiting AP-1 binding. In monocytes, mutations in the NF-kappaB, AP-1, Sp1, or Ets-2 binding sites resulted in complete inhibition of LPS-stimulated IL-12p40 promoter activity using a luciferase-based assay. In contrast, promoter activity was abrogated in THP-1 cells only when the Sp1 or Ets-2 binding sites were mutated. Transcription factor binding to the IL-12p40 promoter following in-vitro HIV infection demonstrated several differences between monocytes and THP-1 cells. Infection with HIV produced an increase in NF-kappaB, AP-1, and Sp1 binding in primary monocytes. In contrast, binding of Ets-2 was dramatically impaired following HIV infection of monocytes, but was unaffected in THP-1 cells. These data clearly show that although LPS induces IL-12p40 expression in primary monocytes and THP-1 cells, the signaling pathways involved and the effect of HIV infection differ and can have disparate effects in these two cell types.
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27
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Abate W, Alghaithy AA, Parton J, Jones KP, Jackson SK. Surfactant lipids regulate LPS-induced interleukin-8 production in A549 lung epithelial cells by inhibiting translocation of TLR4 into lipid raft domains. J Lipid Res 2010; 51:334-44. [PMID: 19648651 PMCID: PMC2803235 DOI: 10.1194/jlr.m000513] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 08/01/2009] [Indexed: 01/24/2023] Open
Abstract
In addition to providing mechanical stability, growing evidence suggests that surfactant lipid components can modulate inflammatory responses in the lung. However, little is known of the molecular mechanisms involved in the immunomodulatory action of surfactant lipids. This study investigates the effect of the lipid-rich surfactant preparations Survanta, Curosurf, and the major surfactant phospholipid dipalmitoylphosphatidylcholine (DPPC) on interleukin-8 (IL-8) gene and protein expression in human A549 lung epithelial cells using immunoassay and PCR techniques. To examine potential mechanisms of the surfactant lipid effects, Toll-like receptor 4 (TLR4) expression was analyzed by flow cytometry, and membrane lipid raft domains were separated by density gradient ultracentrifugation and analyzed by immunoblotting with anti-TLR4 antibody. The lipid-rich surfactant preparations Survanta, Curosurf, and DPPC, at physiological concentrations, significantly downregulated lipopolysaccharide (LPS)-induced IL-8 expression in A549 cells both at the mRNA and protein levels. The surfactant preparations did not affect the cell surface expression of TLR4 or the binding of LPS to the cells. However, LPS treatment induced translocation of TLR4 into membrane lipid raft microdomains, and this translocation was inhibited by incubation of the cells with the surfactant lipid. This study provides important mechanistic details of the immune-modulating action of pulmonary surfactant lipids.
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Affiliation(s)
- Wondwossen Abate
- Centre for Research in Biomedicine, Faculty of Health and Life Science, University of the West of England, Bristol, UK
| | | | - Joan Parton
- Department of Medical Microbiology, School of Medicine, Cardiff University, Cardiff, UK
| | - Kenneth P. Jones
- School of Applied Sciences, University of Wales Institute Cardiff, Cardiff, UK
| | - Simon K. Jackson
- Centre for Research in Biomedicine, Faculty of Health and Life Science, University of the West of England, Bristol, UK
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28
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Hansen C, Pressler T, Nielsen K, Jensen P, Bjarnsholt T, Høiby N. Inflammation in Achromobacter xylosoxidans infected cystic fibrosis patients. J Cyst Fibros 2010; 9:51-8. [DOI: 10.1016/j.jcf.2009.10.005] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 10/26/2009] [Accepted: 10/27/2009] [Indexed: 11/26/2022]
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Tang X, Woodward T, Amar S. A PTP4A3 peptide PIMAP39 modulates TNF-alpha levels and endotoxic shock. J Innate Immun 2009; 2:43-55. [PMID: 20375622 DOI: 10.1159/000235685] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Accepted: 06/17/2009] [Indexed: 11/19/2022] Open
Abstract
Lipopolysaccharide (LPS) stimulation of macrophages initiates intracellular signaling pathways leading to activation of MAPK and its subsequent influence on cytokine production. We recently identified a LITAF-STAT6(B) complex regulated by p38 MAPK in response to LPS stimulation. However, the LPS-induced cascade in the p38/LITAF/TNF signaling pathway remains unclear. Here, we identified PTP4A3, a protein tyrosine phosphotase, as a novel negative regulator of LPS-induced LITAF/TNF-alpha production. PTP4A3 exerts its negative role by dephosphorylating p38 alpha MAPK in response to LPS stimulation of primary macrophages. PTP4A3 expression is upregulated in primary macrophages. Further structure-function analysis revealed that a unique short peptide (PIMAP39) derived from PTP4A3 is capable of mimicking the functionality of full-length PTP4A3 to selectively dephosphorylate p38 alpha and indirectly suppress LPS-induced LITAF-STAT6B complex when it is translocated from the cytoplasmic region to the nucleus of the cell. Treatment of mice with PIMAP39 significantly attenuates the severity of adverse host responses to LPS stimulation, and in some cases provides complete resistance to a lethal dose of LPS due to suppression of TNF-alpha production. All together, these results reveal a previously unrecognized role for the PTP4A3 pathway in response to LPS.
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Affiliation(s)
- Xiaoren Tang
- Department of Periodontology and Oral Biology, Boston University Goldman School of Dental Medicine, Boston, MA 02118, USA
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Hu Y, Chen X, Lin H, Hu Y, Mu X. Study on the antiendotoxin action of Pulsatillae Decoction using an Affymetrix rat genome array. Cell Immunol 2009; 257:32-7. [PMID: 19298953 DOI: 10.1016/j.cellimm.2009.02.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 02/13/2009] [Accepted: 02/17/2009] [Indexed: 01/18/2023]
Abstract
A high-throughput and efficient Affymetrix rat genome array was used to investigate the pharmacological mechanism of the traditional Chinese medicine, Pulsatillae Decoction (PD), used for the treatment of diseases induced by lipopolysaccharide (LPS). Rat intestinal microvascular endothelial cells (RIMECs) were challenged with 1mug/ml LPS for 3h, and then treated with PD at a concentration of 1mg/ml for 24h. Total RNA from each treatment group was extracted from cultured RIMECs for detection by the Affymetrix Rat Genome 230 2.0 Array. The results showed that 36 genes were upregulated and 33 genes were downregulated in the LPS group vs. the blank control group; 566 genes were upregulated and 12 genes were downregulated in the PD-treated group vs. the LPS group; and 93 genes were upregulated and 29 genes were downregulated in the PD-treated group vs. the blank control group. The analysis of these data suggested that PD specifically and effectively reduce damage induced by LPS, and improved physiological and biochemical responses to counteract the effects of LPS.
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Affiliation(s)
- Yiyi Hu
- Institue of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, PR China.
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31
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McClean S, Callaghan M. Burkholderia cepacia complex: epithelial cell–pathogen confrontations and potential for therapeutic intervention. J Med Microbiol 2009; 58:1-12. [DOI: 10.1099/jmm.0.47788-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Burkholderia cepaciacomplex (Bcc) is an important and virulent pathogen in cystic fibrosis patients. The interactions between this pathogen and the host lung epithelium are being widely investigated but remain to be elucidated. The complex is very versatile and its interactions with the lung epithelial cells are many and varied. The first steps in the interaction are penetration of the mucosal blanket and subsequent adherence to the epithelial cell surface. A range of epithelial receptors have been reported to bind to Bcc. The next step in pathogenesis is the invasion of the lung epithelial cell and also translocation across the epithelium to the serosal side. Furthermore, pathogenesis is mediated by a range of virulence factors that elicit their effects on the epithelial cells. This review outlines these interactions and examines the therapeutic implications of understanding the mechanisms of pathogenesis of this difficult, antibiotic-resistant, opportunistic pathogen.
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Affiliation(s)
- Siobhán McClean
- Centre of Microbial Host Interactions, Institute of Technology Tallaght Dublin, Dublin 24, Ireland
| | - Máire Callaghan
- Centre of Microbial Host Interactions, Institute of Technology Tallaght Dublin, Dublin 24, Ireland
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32
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Zheng YJ, Wang YL, Mao EQ, Liu W, Li L, Wu J, Zhang RY, Tang YQ. Gut-derived endotoxin translocation is the main aggravating mechanism of acute severe pancreatitis. BIOSCIENCE HYPOTHESES 2009; 2:286-289. [DOI: 10.1016/j.bihy.2009.03.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
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De Soyza A, Silipo A, Lanzetta R, Govan JR, Molinaro A. Chemical and biological features of Burkholderia cepacia complex lipopolysaccharides. Innate Immun 2008; 14:127-44. [PMID: 18562572 DOI: 10.1177/1753425908093984] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The Burkholderia cepacia complex comprises 10 closely related Gram-negative organisms all of which appear capable of causing disease in humans. These organisms appear of particular relevance to patients with cystic fibrosis. Lipopolysaccharide (LPS) is an important virulence determinant in Gram-negative pathogens. In this review, we highlight important data within the field commenting on LPS/lipid A structure-to-function relationships and cytokine induction capacity of Burkholderia strains studied so far.
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Affiliation(s)
- Anthony De Soyza
- Transplantation and Immunobiology Group, Institute of Cellular Medicine, Newcastle University and The Freeman Hospital, Newcastle-upon-Tyne, UK.
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34
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MacDonald KL, Speert DP. Differential modulation of innate immune cell functions by theBurkholderia cepaciacomplex:Burkholderia cenocepaciabut notBurkholderia multivoransdisrupts maturation and induces necrosis in human dendritic cells. Cell Microbiol 2008; 10:2138-49. [DOI: 10.1111/j.1462-5822.2008.01197.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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35
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Ieranò T, Silipo A, Sturiale L, Garozzo D, Brookes H, Khan CMA, Bryant C, Gould FK, Corris PA, Lanzetta R, Parrilli M, De Soyza A, Molinaro A. The structure and proinflammatory activity of the lipopolysaccharide from Burkholderia multivorans and the differences between clonal strains colonizing pre and posttransplanted lungs. Glycobiology 2008; 18:871-81. [DOI: 10.1093/glycob/cwn074] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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36
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Jackson SK, Abate W, Parton J, Jones S, Harwood JL. Lysophospholipid metabolism facilitates Toll-like receptor 4 membrane translocation to regulate the inflammatory response. J Leukoc Biol 2008; 84:86-92. [PMID: 18403647 DOI: 10.1189/jlb.0907601] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Sepsis, an overwhelming inflammatory response to infection, is a major cause of morbidity and mortality worldwide and has no specific therapy. Phospholipid metabolites, such as lysophospholipids, have been shown to regulate inflammatory responses in sepsis, although their mechanism of action is not well understood. The phospholipid-metabolizing enzymes, lysophospholipid acyltransferases, control membrane phospholipid composition, function, and the inflammatory responses of innate immune cells. Here, we show that lysophosphatidylcholine acyltransferase (LPCAT) regulates inflammatory responses to LPS and other microbial stimuli. Specific inhibition of LPCAT down-regulated inflammatory cytokine production in monocytes and epithelial cells by preventing translocation of TLR4 into membrane lipid raft domains. Our observations demonstrate a new regulatory mechanism that facilitates the innate immune responses to microbial molecular patterns and provide a basis for the anti-inflammatory activity observed in many phospholipid metabolites. This provides the possibility of the development of new classes of anti-inflammatory and antisepsis agents.
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Affiliation(s)
- Simon K Jackson
- Centre for Research in Biomedicine, University of the West of England, Bristol, BS16 1QY, UK.
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37
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Brett PJ, Burtnick MN, Snyder DS, Shannon JG, Azadi P, Gherardini FC. Burkholderia mallei expresses a unique lipopolysaccharide mixture that is a potent activator of human Toll-like receptor 4 complexes. Mol Microbiol 2006; 63:379-90. [PMID: 17163980 PMCID: PMC1974782 DOI: 10.1111/j.1365-2958.2006.05519.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Burkholderia mallei, the aetiologic agent of glanders, causes a variety of illnesses in animals and humans ranging from occult infections to acute fulminating septicaemias. To better understand the role of lipopolysaccharide (LPS) in the pathogenesis of these diseases, studies were initiated to characterize the structural and biological properties of lipid A moieties expressed by this organism. Using a combination of chemical analyses and MALDI-TOF mass spectrometry, B. mallei was shown to express a heterogeneous mixture of tetra- and penta-acylated lipid A species that were non-stoichiometrically substituted with 4-amino-4-deoxy-arabinose residues. The major penta-acylated species consisted of bisphosphorylated d-glucosamine disaccharide backbones possessing two amide linked 3-hydroxyhexadecanoic acids, two ester linked 3-hydroxytetradecanoic acids [C14:0(3-OH)] and an acyloxyacyl linked tetradecanoic acid, whereas, the major tetra-acylated species possessed all but the 3'-linked C14:0(3-OH) residues. In addition, although devoid of hexa-acylated species, B. mallei LPS was shown to be a potent activator of human Toll-like receptor 4 complexes and stimulated human macrophage-like cells (THP-1 and U-937), monocyte-derived macrophages and dendritic cells to produce high levels of TNF-alpha, IL-6 and RANTES. Based upon these results, it appears that B. mallei LPS is likely to play a significant role in the pathogenesis of human disease.
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Affiliation(s)
- Paul J Brett
- Laboratory of Zoonotic Pathogens, Rocky Mountain LaboratoriesNIAID, NIH, Hamilton, MT 59840, USA.
| | - Mary N Burtnick
- Laboratory of Zoonotic Pathogens, Rocky Mountain LaboratoriesNIAID, NIH, Hamilton, MT 59840, USA.
| | - D Scott Snyder
- Complex Carbohydrate Research Center, The University of GeorgiaAthens, GA 30602, USA.
| | - Jeffrey G Shannon
- Laboratory of Intracellular Parasites, Rocky Mountain LaboratoriesNIAID, NIH, Hamilton, MT 59840, USA.
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, The University of GeorgiaAthens, GA 30602, USA.
| | - Frank C Gherardini
- Laboratory of Zoonotic Pathogens, Rocky Mountain LaboratoriesNIAID, NIH, Hamilton, MT 59840, USA.
- For correspondence. E-mail ; Tel. (+1) 406 363 9474; Fax (+1) 406 363 9478
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