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Keogh RA, Haeberle AL, Langouët-Astrié CJ, Kavanaugh JS, Schmidt EP, Moore GD, Horswill AR, Doran KS. Group B Streptococcus adaptation promotes survival in a hyperinflammatory diabetic wound environment. SCIENCE ADVANCES 2022; 8:eadd3221. [PMID: 36367946 PMCID: PMC9651866 DOI: 10.1126/sciadv.add3221] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Diabetic wounds have poor healing outcomes due to the presence of numerous pathogens and a dysregulated immune response. Group B Streptococcus (GBS) is commonly isolated from diabetic wound infections, but the mechanisms of GBS virulence during these infections have not been investigated. Here, we develop a murine model of GBS diabetic wound infection and, using dual RNA sequencing, demonstrate that GBS infection triggers an inflammatory response. GBS adapts to this hyperinflammatory environment by up-regulating virulence factors including those known to be regulated by the two-component system covRS, such as the surface protein pbsP, and the cyl operon, which is responsible for hemolysin/pigmentation production. We recover hyperpigmented/hemolytic GBS colonies from the murine diabetic wound, which we determined encode mutations in covR. We further demonstrate that GBS mutants in cylE and pbsP are attenuated in the diabetic wound. This foundational study provides insight into the pathogenesis of GBS diabetic wound infections.
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Affiliation(s)
- Rebecca A. Keogh
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
| | - Amanda L. Haeberle
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
| | | | - Jeffrey S. Kavanaugh
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
| | - Eric P. Schmidt
- Department of Medicine–Pulmonary Sciences and Critical Care, University of Colorado Anschutz, Aurora, CO, USA
| | - Garrett D. Moore
- Department of Orthopedics, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Alexander R. Horswill
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
- Department of Veterans Affairs Eastern Colorado Healthcare System, Aurora, CO, USA
| | - Kelly S. Doran
- Department of Immunology and Microbiology, University of Colorado Anschutz, Aurora, CO, USA
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Ielapi N, Caprino F, Malizia B, Sisinni A, Ssempijja L, Andreucci M, Licastro N, Serra R. Infection, Infectious Agents and Vascular Disease. Rev Recent Clin Trials 2021; 16:262-271. [PMID: 33823769 DOI: 10.2174/1574887116666210325124045] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/29/2021] [Accepted: 02/23/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Infectious agents may be involved in the pathogenesis of vascular disease and related complications. The aim of this review is to analyze the most relevant information on the common infections related to vascular disease, discussing the main pathophysiological mechanisms. METHODS In the current review, the most important evidence on the issue of infections and vascular disease is searched on Medline, Scopus, and ScienceDirect database. RESULTS Among infectious agents, herpesviruses, parvovirus B19, hepatitis viruses, human immunodeficiency virus, severe acute respiratory syndrome coronavirus 2, treponema pallidum, mycobacterium tuberculosis, pseudomonas aeruginosa, staphylococcus aureus, and candida albicans seem to particularly related to vascular disease. CONCLUSION Infectious agents may affect vessel's homeostasis and functionality, both on the arterial and venous side, by means of several pathophysiological mechanisms such as dysregulation in vasomotor function, thromboembolic complications, initiation and progression of atherosclerosis, alteration of perivascular adipose tissue, recruiting inflammatory cells and molecules.
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Affiliation(s)
- Nicola Ielapi
- Interuniversity Center of Phlebolymphology (CIFL). International Research and Educational Program in Clinical and Experimental Biotechnology" at the Department of Surgical and Medical Sciences University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro, Italy
| | - Francesco Caprino
- Interuniversity Center of Phlebolymphology (CIFL). International Research and Educational Program in Clinical and Experimental Biotechnology" at the Department of Surgical and Medical Sciences University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro, Italy
| | - Biagio Malizia
- Interuniversity Center of Phlebolymphology (CIFL). International Research and Educational Program in Clinical and Experimental Biotechnology" at the Department of Surgical and Medical Sciences University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro, Italy
| | - Antonio Sisinni
- Interuniversity Center of Phlebolymphology (CIFL). International Research and Educational Program in Clinical and Experimental Biotechnology" at the Department of Surgical and Medical Sciences University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro, Italy
| | - Lwanga Ssempijja
- Interuniversity Center of Phlebolymphology (CIFL). International Research and Educational Program in Clinical and Experimental Biotechnology" at the Department of Surgical and Medical Sciences University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro, Italy
| | - Michele Andreucci
- Department of Health Sciences, University of Catanzaro, Catanzaro, Italy
| | - Noemi Licastro
- Interuniversity Center of Phlebolymphology (CIFL). International Research and Educational Program in Clinical and Experimental Biotechnology" at the Department of Surgical and Medical Sciences University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro, Italy
| | - Raffaele Serra
- Interuniversity Center of Phlebolymphology (CIFL). International Research and Educational Program in Clinical and Experimental Biotechnology" at the Department of Surgical and Medical Sciences University Magna Graecia of Catanzaro, Viale Europa 88100 Catanzaro, Italy
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Ramani K, Garg AV, Jawale CV, Conti HR, Whibley N, Jackson EK, Shiva SS, Horne W, Kolls JK, Gaffen SL, Biswas PS. The Kallikrein-Kinin System: A Novel Mediator of IL-17-Driven Anti-Candida Immunity in the Kidney. PLoS Pathog 2016; 12:e1005952. [PMID: 27814401 PMCID: PMC5096720 DOI: 10.1371/journal.ppat.1005952] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 09/25/2016] [Indexed: 11/19/2022] Open
Abstract
The incidence of life-threatening disseminated Candida albicans infections is increasing in hospitalized patients, with fatalities as high as 60%. Death from disseminated candidiasis in a significant percentage of cases is due to fungal invasion of the kidney, leading to renal failure. Treatment of candidiasis is hampered by drug toxicity, the emergence of antifungal drug resistance and lack of vaccines against fungal pathogens. IL-17 is a key mediator of defense against candidiasis. The underlying mechanisms of IL-17-mediated renal immunity have so far been assumed to occur solely through the regulation of antimicrobial mechanisms, particularly activation of neutrophils. Here, we identify an unexpected role for IL-17 in inducing the Kallikrein (Klk)-Kinin System (KKS) in C. albicans-infected kidney, and we show that the KKS provides significant renal protection in candidiasis. Microarray data indicated that Klk1 was upregulated in infected kidney in an IL-17-dependent manner. Overexpression of Klk1 or treatment with bradykinin rescued IL-17RA-/- mice from candidiasis. Therapeutic manipulation of IL-17-KKS pathways restored renal function and prolonged survival by preventing apoptosis of renal cells following C. albicans infection. Furthermore, combining a minimally effective dose of fluconazole with bradykinin markedly improved survival compared to either drug alone. These results indicate that IL-17 not only limits fungal growth in the kidney, but also prevents renal tissue damage and preserves kidney function during disseminated candidiasis through the KKS. Since drugs targeting the KKS are approved clinically, these findings offer potential avenues for the treatment of this fatal nosocomial infection.
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Affiliation(s)
- Kritika Ramani
- Department of Medicine, Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Abhishek V. Garg
- Department of Medicine, Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Chetan V. Jawale
- Department of Medicine, Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Heather R. Conti
- Department of Biological Sciences, University of Toledo, Toledo, Ohio, United States of America
| | - Natasha Whibley
- Department of Medicine, Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Edwin K. Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Sruti S. Shiva
- Vascular Medicine Institute, Dept. of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - William Horne
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jay K. Kolls
- Richard King Mellon Foundation Institute for Pediatric Research, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Sarah L. Gaffen
- Department of Medicine, Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Partha S. Biswas
- Department of Medicine, Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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Shin YH, Kojima Y, Maeda H, Otagiri M. Conjugation of Succinylated Gelatin to Soybean Trypsin Inhibitor. J BIOACT COMPAT POL 2016. [DOI: 10.1177/088391159601100101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Kunitz-type soybean trypsin inhibitor (SBTI) and succinylated gelatin fragment (Suc-gel) were conjugated by using water-soluble carbodiimide, and physicochemical and biopharmaceutical properties of the conjugate (Suc-gel-SBTI) were characterized. The conjugate contains about 2.5 mol of Suc-gel with a mean molecular weight of 32,000 per mole of SBTI, based on the content of hydroxyproline. After iv injection of the radiolabeled conjugate or native SBTI into mice, it was found that native SBTI showed rapid elimination from plasma ( t½α = 2 min), whereas Suc-gel-SBTI was slowly ( t½α = 2 min) eliminated. Organ distribution of the two agents at 30 min after iv injection was different: Suc-gel-SBTI accumulated to a large extent in both the liver and the spleen, about 23.4 and 6.9%, respectively which was more than the native SBTI. Native SBTI was taken up more rapidly by the kidney (~ 45%) and excreted into the urine (~34%) before it accumulated in other organs and tissues. In addition, we evaluated the pharmacological effects of these agents in an animal model. Suc-gel-SBTI was more effective than native SBTI against trypsin-induced lethal shock in mice. This polymer-conjugated SBTI seems to exhibit better pharmacological and therapeutic properties than its native counterpart.
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Affiliation(s)
- Young-Hee Shin
- Department of Microbiology, Kumamoto University School of Medicine, Kumamoto 860, Japan
| | - Yuichiro Kojima
- Department of Microbiology, Kumamoto University School of Medicine, Kumamoto 860, Japan
| | - Hiroshi Maeda
- Department of Microbiology, Kumamoto University School of Medicine, Kumamoto 860, Japan
| | - Masaki Otagiri
- Faculty of Pharmaceutical Science, Kumamoto University, Kumamoto 862, Japan
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Maeda H. Tumor-selective delivery of macromolecular drugs via the EPR effect: background and future prospects. Bioconjug Chem 2010; 21:797-802. [PMID: 20397686 DOI: 10.1021/bc100070g] [Citation(s) in RCA: 707] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
This paper briefly documents the history of the discovery of the EPR (enhanced permeability and retention) effect and elucidates an analogy between bacterial infection involving proteases that trigger kinin generation and cancer. The EPR effect of macromolecules in cancer tissues is defined, and the distinction between the EPR effect (with reference to clearance of macromolecules from the interstitial space of tumor tissues) and the simple passive targeting of drugs to tumors is described. Additional points of discussion include the uniqueness of tumor vessels, the influence of kinin and other vascular mediators such as nitric oxide (NO) and prostaglandins, and the heterogeneity of the EPR effect. Two different strategies to augment the EPR effect that were discovered are elevating blood pressure artificially via slow infusion of angiotensin II and applying nitroglycerin or other NO donors. Use of the nitroagent increased not only the blood flow of the tumor, but also the delivery of drug to the tumor and the drug's therapeutic effect. This finding shows an intriguing analogy to hypoxic cardiac infarct tissue, in that both are improved by NO. These two methods were applied to treatment of rodents and human cancers, in combination with other anticancer agents, with successful results achieved in rodents as well as humans. These data suggest very appealing prospects for utilization of the EPR effect in future development of cancer therapeutics.
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Affiliation(s)
- Hiroshi Maeda
- Laboratory of Microbiology and Oncology, Faculty of Pharmaceutical Sciences, Division of Applied Chemistry, Graduate School of Engineering, Sojo University, Kumamoto, 860-0082, Japan.
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6
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Richards GP, Nuñez A. Specificity of a Vibrio vulnificus aminopeptidase toward kinins and other peptidyl substrates. J Bacteriol 2006; 188:2056-62. [PMID: 16513735 PMCID: PMC1428149 DOI: 10.1128/jb.188.6.2056-2062.2006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recently, phosphoglucose isomerase with a lysyl aminopeptidase (PGI-LysAP) activity was identified in Vibrio vulnificus. In this paper, we demonstrate the proteolytic cleavage of human-derived peptides by PGI-LysAP of V. vulnificus using three approaches: (i) a quantitative fluorescent ninhydrin assay for free lysine, (ii) matrix-assisted laser desorption ionization-two-stage time of flight mass spectrometry (MALDI-TOF-TOF), and (iii) Tricine gel electrophoresis. PGI-LysAP hydrolyzed bradykinin, Lys-bradykinin, Lys-(des-Arg9)-bradykinin, neurokinin A, Met-Lys-bradykinin, histatin 8, and a myosin light chain fragment. We detected the proteolytic release of free L-lysine from peptide digests using a rapid, simple, sensitive, and quantitative fluorescent ninhydrin assay, and results were confirmed by MALDI-TOF-TOF. The use of the fluorescent ninhydrin assay to quantitatively detect free lysine hydrolyzed from peptides is the first application of its kind and serves as a paradigm for future studies. The visualization of peptide hydrolysis was accomplished by Tricine gel electrophoresis. Proteolytic processing of kinins alters their affinities toward specific cellular receptors and initiates signal transduction mechanisms responsible for inflammation, vasodilation, and enhanced vascular permeability. By applying novel approaches to determine the proteolytic potential of bacterial enzymes, we demonstrate that PGI-LysAP has broad exopeptidase activity which may enhance V. vulnificus invasiveness by altering peptides involved in signal transduction pathways.
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Affiliation(s)
- Gary P Richards
- USDA, ARS, Microbial Food Safety Research Unit, Delaware State University, 1200 N. DuPont Hwy., James W. W. Baker Center, Dover, DE 19901, USA.
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Popov SG, Popova TG, Hopkins S, Weinstein RS, MacAfee R, Fryxell KJ, Chandhoke V, Bailey C, Alibek K. Effective antiprotease-antibiotic treatment of experimental anthrax. BMC Infect Dis 2005; 5:25. [PMID: 15819985 PMCID: PMC1090577 DOI: 10.1186/1471-2334-5-25] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2005] [Accepted: 04/08/2005] [Indexed: 11/13/2022] Open
Abstract
Background Inhalation anthrax is characterized by a systemic spread of the challenge agent, Bacillus anthracis. It causes severe damage, including multiple hemorrhagic lesions, to host tissues and organs. It is widely believed that anthrax lethal toxin secreted by proliferating bacteria is a major cause of death, however, the pathology of intoxication in experimental animals is drastically different from that found during the infectious process. In order to close a gap between our understanding of anthrax molecular pathology and the most prominent clinical features of the infectious process we undertook bioinformatic and experimental analyses of potential proteolytic virulence factors of B. anthracis distinct from lethal toxin. Methods Secreted proteins (other than lethal and edema toxins) produced by B. anthracis were tested for tissue-damaging activity and toxicity in mice. Chemical protease inhibitors and rabbit immune sera raised against B. anthracis proteases were used to treat mice challenged with B. anthracis (Sterne) spores. Results B. anthracis strain delta Ames (pXO1-, pXO2-) producing no lethal and edema toxins secrets a number of metalloprotease virulence factors upon cultivation under aerobic conditions, including those with hemorrhagic, caseinolytic and collagenolytic activities, belonging to M4 and M9 thermolysin and bacterial collagenase families, respectively. These factors are directly toxic to DBA/2 mice upon intratracheal administration at 0.5 mg/kg and higher doses. Chemical protease inhibitors (phosphoramidon and 1, 10-phenanthroline), as well as immune sera against M4 and M9 proteases of B. anthracis, were used to treat mice challenged with B. anthracis (Sterne) spores. These substances demonstrate a substantial protective efficacy in combination with ciprofloxacin therapy initiated as late as 48 h post spore challenge, compared to the antibiotic alone. Conclusion Secreted proteolytic enzymes are important pathogenic factors of B. anthrasis, which can be considered as effective therapeutic targets in the development of anthrax treatment and prophylactic approaches complementing anti-lethal toxin therapy.
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Affiliation(s)
- Serguei G Popov
- Advanced Biosystems, Inc., Manassas, VA, USA
- Current affiliation: National Center for Biodefense, George Mason University, Manassas, VA, USA
| | - Taissia G Popova
- Advanced Biosystems, Inc., Manassas, VA, USA
- Current affiliation: National Center for Biodefense, George Mason University, Manassas, VA, USA
| | | | | | | | - Karl J Fryxell
- Center for Biomedical Genomics & Informatics, Department of Molecular & Microbiology, George Mason University, Manassas, VA, USA
| | - Vikas Chandhoke
- National Center for Biodefense, George Mason University, Manassas, VA, USA
| | - Charles Bailey
- National Center for Biodefense, George Mason University, Manassas, VA, USA
| | - Ken Alibek
- Advanced Biosystems, Inc., Manassas, VA, USA
- National Center for Biodefense, George Mason University, Manassas, VA, USA
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9
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Stewart JM, Gera L, York EJ, Chan DC, Bunn P. Bradykinin antagonists: present progress and future prospects. IMMUNOPHARMACOLOGY 1999; 43:155-61. [PMID: 10596848 DOI: 10.1016/s0162-3109(99)00102-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Bradykinin (BK) antagonist peptides have been powerful tools for delineating roles of kinins in both normal and pathological physiology and offer promise of drug development for a variety of inflammatory conditions and cancers. At the present time, potent peptide antagonists are available that are either specific for BK B1 or B2 receptors, or are effective on both receptor classes. Non-peptide BK B2 antagonists are now being announced and are under investigation in several companies. The best peptide B1-B2 peptide antagonist is stable against all kininases, is orally available, and has a very long lifetime in vivo. Certain dimers of this antagonist, as well as several smaller molecules, are active against several cancers, both in vitro and in vivo.
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Affiliation(s)
- J M Stewart
- Department of Biochemistry and Molecular Genetics, University of Colorado Medical School, Denver 80262, USA.
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Stewart JM, Gera L, Chan DC, Whalley ET, Hanson WL, Zuzack JS. Potent, long-acting, orally-active bradykinin antagonists for a wide range of applications. IMMUNOPHARMACOLOGY 1997; 36:167-72. [PMID: 9228542 DOI: 10.1016/s0162-3109(97)00017-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Actions of bradykinin (Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg; BK) are mediated by constitutively expressed B2 receptors, that require the full BK peptide chain, and by B1 receptors, induced in inflammation, that use BK(1-8) as ligand. In addition to many physiological and pathophysiological functions, the growth factor activity of BK evidently allows it to act as an autocrine stimulant for small cell lung cancer. A new group of BK antagonists containing the novel amino acid a-(2-indanyl)glycine provides extremely potent broad-spectrum as well as selective antagonists for all these functions.
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Affiliation(s)
- J M Stewart
- Department of Biochemistry, University of Colorado Medical School, Denver 80262, USA.
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Affiliation(s)
- H Maeda
- Department of Microbiology, Kumamoto University School of Medicine, Japan
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12
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Vollmer P, Walev I, Rose-John S, Bhakdi S. Novel pathogenic mechanism of microbial metalloproteinases: liberation of membrane-anchored molecules in biologically active form exemplified by studies with the human interleukin-6 receptor. Infect Immun 1996; 64:3646-51. [PMID: 8751912 PMCID: PMC174276 DOI: 10.1128/iai.64.9.3646-3651.1996] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Certain membrane-anchored proteins, including several cytokines and cytokine receptors, can be released into cell supernatants through the action of endogenous membrane-bound metalloproteinases. The shed molecules are then able to fulfill various biological functions; for example, soluble interleukin-6 receptor (sIL-6R) can bind to bystander cells, rendering these cells sensitive to the action of IL-6. Using IL-6R as a model substrate, we report that the metalloproteinase from Serratia marcescens mimics the action of the endogenous shedding proteinase. Treatment of human monocytes with the bacterial protease led to a rapid release of sIL-6R into the supernatant. This effect was inhibitable with TAPI [N-(D,L-[2-(hydroxyaminocarbonyl)methyl]-4-methylpentanoyl) L-3-(2' naphthyl)-alanyl-L-alanine, 2-aminoethyl amide], a specific inhibitor of the membrane-bound intrinsic metalloproteinase, but not with other conventional proteinase inhibitors. sIL-6R-liberating activity was also detected in culture supernatants of Staphylococcus aureus, Pseudomonas aeruginosa, and Listeria monocytogenes, organisms that are known to produce metalloproteinases. sIL-6R released through the action of S. marcescens metalloproteinase retained biological activity and rendered IL-6-unresponsive human hepatoma cells sensitive to stimulation with IL-6. This was shown by Northern (RNA) blot detection of haptoglobin mRNA and by quantitative measurements of de novo-synthesized haptoglobin in cell supernatants. Analysis of immunoprecipitated, radiolabeled sIL-6R revealed that the bacterial protease cleaved IL-6R at a site distinct from that utilized by the endogenous protease. These studies show that membrane-anchored proteins can be released in active form through cleavage at multiple sites, and they uncover a novel mechanism via which microbial proteases possibly provoke long-range biological effects in the host organism.
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Affiliation(s)
- P Vollmer
- First Department of Medicine-Pathophysiology Section, Johannes Gutenberg-University of Mainz, Germany
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Abstract
Bradykinin (BK) is involved in regulation of every major physiological system and is an initiator or mediator of many pathophysiological conditions. Rapid progress in understanding these aspects of BK biology has come since the discovery of BK antagonists. This article reviews principal points in the history of the kallikrein-kinin field and of kinin biology. The chemistry and development of antagonists for B1 and B2 kinin receptors is discussed. Uses of the antagonists in biomedical research and potential clinical applications are presented.
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Affiliation(s)
- J M Stewart
- Department of Biochemistry, University of Colorado Medical School, Denver 80262
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