1
|
Resolving the genetics of human tryptases: implications for health, disease, and clinical use as a biomarker. Curr Opin Allergy Clin Immunol 2022; 22:143-152. [PMID: 35197435 DOI: 10.1097/aci.0000000000000813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE OF REVIEW To discuss our evolving understanding of the genetic variation in human tryptases and recent advances in associated clinical phenotypes. RECENT FINDINGS Serum tryptase levels have long been used as biomarkers in clinical practice to diagnose mast cell-associated disorders and mast cell-mediated reactions but the contribution of specific secreted isoforms of human tryptases and their role(s) in health and disease has only recently begun to be illuminated. It is now recognized that hereditary alpha-tryptasemia (HαT) is a common genetic trait and the commonest cause for elevated basal serum tryptase (BST), where it can both contribute to mast cell-associated phenotypes, and potentially confound their correct diagnosis. Expression of different tryptase isoforms is now recognized to be associated with specific clinical phenotypes including clonal and nonclonal mast cell-associated disorders as well as certain asthma endotypes. These disparate impacts on clinical disorders may result from differences in enzymatic activities of mature α-tryptases and β-tryptases, and the unique substrate profile and stability of heterotetrameric mature α/β-tryptases recently described to naturally occur. SUMMARY Variable copy number and isoform expression of tryptases differentially impact diseases and reactions associated with mast cells in humans. Recent advances in understanding of genetics governing BST levels have refined our understanding and the clinical use of this biomarker. In the future, incorporation of tryptase genotyping will likely be integral to the work-up and trial design of patients with phenotypes impacted by mast cells ranging from asthma to mastocytosis.
Collapse
|
2
|
Mast cell tryptases in allergic inflammation and immediate hypersensitivity. Curr Opin Immunol 2021; 72:94-106. [PMID: 33932709 DOI: 10.1016/j.coi.2021.04.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/01/2021] [Accepted: 04/01/2021] [Indexed: 02/07/2023]
Abstract
Dysregulated mast cell-mediated inflammation and/or activation have been linked to a number of human diseases, including asthma, anaphylaxis, chronic spontaneous urticaria, and mast cell activation syndromes. As a major mast cell granule protein, tryptase is a biomarker commonly used in clinical practice to diagnose mast cell-associated disorders and -mediated reactions, but its mechanistic roles in disease pathogenesis remains incompletely understood. Here, we summarize recent advances in the understanding of human tryptase genetics and the effects that different genetic composition may have on the quaternary structure of tetrameric mature tryptases. We also discuss how these differences may impact clinical phenotypes including allergic inflammation, immediate hypersensitivity, and others seen in patients with mast cell-associated disorders. With the increased application of next-generation sequencing, we foresee that human genetic approaches will be a major focus of understanding human tryptase functions in various human mast cell disorders and in new therapeutic development.
Collapse
|
3
|
Falduto GH, Pfeiffer A, Luker A, Metcalfe DD, Olivera A. Emerging mechanisms contributing to mast cell-mediated pathophysiology with therapeutic implications. Pharmacol Ther 2020; 220:107718. [PMID: 33130192 DOI: 10.1016/j.pharmthera.2020.107718] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/26/2020] [Indexed: 02/07/2023]
Abstract
Mast cells are tissue-resident immune cells that play key roles in the initiation and perpetuation of allergic inflammation, usually through IgE-mediated mechanisms. Mast cells are, however, evolutionary ancient immune cells that can be traced back to urochordates and before the emergence of IgE antibodies, suggesting their involvement in antibody-independent biological functions, many of which are still being characterized. Herein, we summarize recent advances in understanding the roles of mast cells in health and disease, partly through the study of emerging non-IgE receptors such as the Mas-related G protein-coupled receptor X2, implicated in pseudo-allergic reactions as well as in innate defense and neuronal sensing; the mechano-sensing adhesion G protein-coupled receptor E2, variants of which are associated with familial vibratory urticaria; and purinergic receptors, which orchestrate tissue damage responses similarly to the IL-33 receptor. Recent evidence also points toward novel mechanisms that contribute to mast cell-mediated pathophysiology. Thus, in addition to releasing preformed mediators contained in granules and synthesizing mediators de novo, mast cells also secrete extracellular vesicles, which convey biological functions. Understanding their release, composition and uptake within a variety of clinical conditions will contribute to the understanding of disease specific pathology and likely lead the way to novel therapeutic approaches. We also discuss recent advances in the development of therapies targeting mast cell activity, including the ligation of inhibitory ITIM-containing receptors, and other strategies that suppress mast cells or responses to mediators for the management of mast cell-related diseases.
Collapse
Affiliation(s)
- Guido H Falduto
- Mast Cell Biology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Annika Pfeiffer
- Mast Cell Biology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Andrea Luker
- Mast Cell Biology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Dean D Metcalfe
- Mast Cell Biology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Ana Olivera
- Mast Cell Biology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
4
|
Ren Y, Lyu Y, Mereness JA, Wang S, Pang J, Mariani TJ. Rare Pulmonary Connective Tissue Type Mast Cells Regulate Lung Endothelial Cell Angiogenesis. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 190:1763-1773. [PMID: 32450152 PMCID: PMC9808505 DOI: 10.1016/j.ajpath.2020.04.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/24/2020] [Accepted: 04/27/2020] [Indexed: 01/07/2023]
Abstract
Within the human lung, mast cells typically reside adjacent to the conducting airway and assume a mucosal phenotype (MCT). In rare pathologic conditions, connective tissue phenotype mast cells (MCTCs) can be found in the lung parenchyma. MCTCs accumulate in the lungs of infants with severe bronchopulmonary dysplasia, a chronic lung disease associated with preterm birth, which is characterized by pulmonary vascular dysmorphia. The human mast cell line (LUVA) was used to model MCTCs or MCTs. The ability of MCTCs to affect vascular organization during fetal lung development was tested in mouse lung explant cultures. The effect of MCTCs on in vitro tube formation and barrier function was studied using primary fetal human pulmonary microvascular endothelial cells. The mechanistic role of MCTC proteases was tested using inhibitors. MCTCLUVA but not MCTLUVA was associated with vascular dysmorphia in lung explants. In vitro, the addition of MCTCLUVA potentiated fetal human pulmonary microvascular endothelial cell interactions, inhibited tube stability, and disrupted endothelial cell junctions. Protease inhibitors ameliorated the ability of MCTCLUVA to alter endothelial cell angiogenic activities in vitro and ex vivo. These data indicate that MCTCs may directly contribute to disrupted angiogenesis in bronchopulmonary dysplasia. A better understanding of factors that regulate mast cell subtype and their different effector functions is essential.
Collapse
Affiliation(s)
- Yue Ren
- Division of Neonatology and Pediatric Molecular and Personalized Medicine Program, University of Rochester, Rochester, New York,Department of Biology, University of Rochester, Rochester, New York
| | - Yuyan Lyu
- Department of Pediatrics, University of Rochester, Rochester, New York
| | - Jared A. Mereness
- Division of Neonatology and Pediatric Molecular and Personalized Medicine Program, University of Rochester, Rochester, New York,Department of Biomedical Genetics, University of Rochester, Rochester, New York
| | - Shumin Wang
- Department of Pediatrics, University of Rochester, Rochester, New York,Aab Cardiovascular Research Institute, University of Rochester, Rochester, New York
| | - Jinjiang Pang
- Department of Pediatrics, University of Rochester, Rochester, New York,Aab Cardiovascular Research Institute, University of Rochester, Rochester, New York
| | - Thomas J. Mariani
- Division of Neonatology and Pediatric Molecular and Personalized Medicine Program, University of Rochester, Rochester, New York,Department of Biomedical Genetics, University of Rochester, Rochester, New York,Address correspondence to Thomas J. Mariani, Ph.D., Pediatric Molecular and Personalized Medicine Program, Division of Neonatology, University of Rochester Medical Center, 601 Elmwood Ave., Box 850, Rochester, NY 14642.
| |
Collapse
|
5
|
Maun HR, Jackman JK, Choy DF, Loyet KM, Staton TL, Jia G, Dressen A, Hackney JA, Bremer M, Walters BT, Vij R, Chen X, Trivedi NN, Morando A, Lipari MT, Franke Y, Wu X, Zhang J, Liu J, Wu P, Chang D, Orozco LD, Christensen E, Wong M, Corpuz R, Hang JQ, Lutman J, Sukumaran S, Wu Y, Ubhayakar S, Liang X, Schwartz LB, Babina M, Woodruff PG, Fahy JV, Ahuja R, Caughey GH, Kusi A, Dennis MS, Eigenbrot C, Kirchhofer D, Austin CD, Wu LC, Koerber JT, Lee WP, Yaspan BL, Alatsis KR, Arron JR, Lazarus RA, Yi T. An Allosteric Anti-tryptase Antibody for the Treatment of Mast Cell-Mediated Severe Asthma. Cell 2020; 179:417-431.e19. [PMID: 31585081 DOI: 10.1016/j.cell.2019.09.009] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 07/09/2019] [Accepted: 09/05/2019] [Indexed: 12/18/2022]
Abstract
Severe asthma patients with low type 2 inflammation derive less clinical benefit from therapies targeting type 2 cytokines and represent an unmet need. We show that mast cell tryptase is elevated in severe asthma patients independent of type 2 biomarker status. Active β-tryptase allele count correlates with blood tryptase levels, and asthma patients carrying more active alleles benefit less from anti-IgE treatment. We generated a noncompetitive inhibitory antibody against human β-tryptase, which dissociates active tetramers into inactive monomers. A 2.15 Å crystal structure of a β-tryptase/antibody complex coupled with biochemical studies reveal the molecular basis for allosteric destabilization of small and large interfaces required for tetramerization. This anti-tryptase antibody potently blocks tryptase enzymatic activity in a humanized mouse model, reducing IgE-mediated systemic anaphylaxis, and inhibits airway tryptase in Ascaris-sensitized cynomolgus monkeys with favorable pharmacokinetics. These data provide a foundation for developing anti-tryptase as a clinical therapy for severe asthma.
Collapse
Affiliation(s)
- Henry R Maun
- Department of Early Discovery Biochemistry, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Janet K Jackman
- Department of Immunology Discovery, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - David F Choy
- Department of Biomarker Discovery OMNI, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Kelly M Loyet
- Department of Biochemical and Cellular Pharmacology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Tracy L Staton
- Department of OMNI Biomarker Development, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Guiquan Jia
- Department of Biomarker Discovery OMNI, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Amy Dressen
- Department of Human Genetics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Jason A Hackney
- Department of Bioinformatics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Meire Bremer
- Department of OMNI Biomarker Development, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Benjamin T Walters
- Department of Biochemical and Cellular Pharmacology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Rajesh Vij
- Department of Antibody Engineering, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Xiaocheng Chen
- Department of Antibody Engineering, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Neil N Trivedi
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA; Veterans Affairs Medical Center, San Francisco, CA 94121, USA
| | - Ashley Morando
- Department of Biochemical and Cellular Pharmacology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Michael T Lipari
- Department of Early Discovery Biochemistry, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Yvonne Franke
- Depratment of Biomolecular Resources, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Xiumin Wu
- Department of Translational Immunology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Juan Zhang
- Department of Translational Immunology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - John Liu
- Department of Translational Immunology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Ping Wu
- Department of Structural Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Diana Chang
- Department of Human Genetics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Luz D Orozco
- Department of Bioinformatics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Erin Christensen
- Department of Protein Chemistry, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Manda Wong
- Department of Structural Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Racquel Corpuz
- Department of Structural Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Julie Q Hang
- Department of Protein Chemistry, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Jeff Lutman
- Department of Preclinical and Translational Pharmacokinetics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Siddharth Sukumaran
- Department of Preclinical and Translational Pharmacokinetics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Yan Wu
- Department of Antibody Engineering, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Savita Ubhayakar
- Department of Drug Metabolism and Pharmacokinetics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Xiaorong Liang
- Department of Drug Metabolism and Pharmacokinetics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Lawrence B Schwartz
- Department of Internal Medicine, Division of Rheumatology, Allergy and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Magda Babina
- Department of Dermatology and Allergy, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Prescott G Woodruff
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - John V Fahy
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Rahul Ahuja
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA; Veterans Affairs Medical Center, San Francisco, CA 94121, USA
| | - George H Caughey
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA; Veterans Affairs Medical Center, San Francisco, CA 94121, USA
| | - Aija Kusi
- Department of Safety Assessment, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Mark S Dennis
- Department of Antibody Engineering, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Charles Eigenbrot
- Department of Structural Biology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Daniel Kirchhofer
- Department of Early Discovery Biochemistry, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Cary D Austin
- Department of Pathology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Lawren C Wu
- Department of Immunology Discovery, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - James T Koerber
- Department of Antibody Engineering, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Wyne P Lee
- Department of Translational Immunology, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Brian L Yaspan
- Department of Human Genetics, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Kathila R Alatsis
- Department of Safety Assessment, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA
| | - Joseph R Arron
- Department of Immunology Discovery, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
| | - Robert A Lazarus
- Department of Early Discovery Biochemistry, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
| | - Tangsheng Yi
- Department of Immunology Discovery, Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
| |
Collapse
|
6
|
Choy DF, Arron JR. Beyond type 2 cytokines in asthma - new insights from old clinical trials. Expert Opin Ther Targets 2020; 24:463-475. [PMID: 32223656 DOI: 10.1080/14728222.2020.1744567] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Introduction: Human asthma is a heterogeneous disorder on molecular, pathological, and clinical levels. The paradigm of asthma as an allergic process driven by type 2 cytokines and mediators has led to targeted biologic therapies resulting in some clinical benefit in patient subsets. However, some patient subsets and clinical manifestations do not benefit from these interventions, thus redefining unmet needs. Clinical studies of type 2 directed therapies have identified new targets under investigation in clinical development; these include epithelial alarmins, non-type 2 cytokines, cytokine receptor signaling, mast cells and neuroinflammation.Areas covered: We consider lessons learned concerning asthma pathogenesis from observational studies and clinical trials of biologic agents that target type 2 mediators. We also provide a perspective on emerging therapeutic hypotheses to target processes independent of or orthogonal to type 2 inflammation in asthma.Expert opinion: Type 2 inflammation is continuous, not discrete, and is likely a modifier of underlying dysregulated airway physiology. Non-type 2 inflammatory mediators (e.g., IL17, IL6, IFNs), microbiome, alarmins (e.g., TSLP, IL33), mast cells and sensory neurons may represent orthogonal targets to type 2 mediators. There is a need to better match targets and outcome measures in biologically defined patient populations to appropriately test hypotheses in the clinic.
Collapse
|
7
|
Giardina SF, Werner DS, Pingle M, Bergstrom DE, Arnold LD, Barany F. A Novel, Nonpeptidic, Orally Active Bivalent Inhibitor of Human β-Tryptase. Pharmacology 2018; 102:233-243. [PMID: 30134249 PMCID: PMC6242772 DOI: 10.1159/000492078] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 07/06/2018] [Indexed: 01/15/2023]
Abstract
β-Tryptase is released from mast cells upon degranulation in response to allergic and inflammatory stimuli. Human tryptase is a homotetrameric serine protease with 4 identical active sites directed toward a central pore. These active sites present an optimized scenario for the rational design of bivalent inhibitors, which bridge 2 adjacent active sites. Using (3-[1-acylpiperidin-4-yl]phenyl)methanamine as the pharmacophoric core and a disiloxane linker to span 2 active sites we have successfully produced a novel bivalent tryptase inhibitor, compound 1a, with a comparable profile to previously described inhibitors. Pharmacological properties of compound 1a were studied in a range of in vitro enzymic and cellular screening assays, and in vivo xenograft models. This non-peptide inhibitor of tryptase demonstrated superior activity (IC50 at 100 pmol/L tryptase = 1.82 nmol/L) compared to monomeric modes of inhibition. X-ray crystallography validated the dimeric mechanism of inhibition, and 1a demonstrated good oral bioavailability and efficacy in HMC-1 xenograft models. Furthermore, compound 1a demonstrated extremely slow off rates and high selectivity against-related proteases. This highly potent, orally bioavailable and selective inhibitor of human tryptase will be an invaluable tool in future studies to explore the therapeutic potential of attenuating the activity of this elusive target.
Collapse
Affiliation(s)
- Sarah F Giardina
- Department of Microbiology and Immunology, Joan and Sanford I. Weill Medical College of Cornell University, New York, New York, USA,
| | - Douglas S Werner
- Coferon, Inc., 25 Health Sciences Drive, Stony Brook, New York, USA
- BlinkBio, Inc., The Scripps Research Institute, Jupiter, Florida, USA
| | - Maneesh Pingle
- Department of Microbiology and Immunology, Joan and Sanford I. Weill Medical College of Cornell University, New York, New York, USA
- Coferon, Inc., 25 Health Sciences Drive, Stony Brook, New York, USA
- BlinkBio, Inc., The Scripps Research Institute, Jupiter, Florida, USA
| | - Donald E Bergstrom
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA
| | - Lee D Arnold
- Coferon, Inc., 25 Health Sciences Drive, Stony Brook, New York, USA
- Fount Therapeutics, LLC, Wilmington, Delaware, USA
| | - Francis Barany
- Department of Microbiology and Immunology, Joan and Sanford I. Weill Medical College of Cornell University, New York, New York, USA
| |
Collapse
|
8
|
Khedr MEMS, Abdelmotelb AM, Pender SLF, Zhou X, Walls AF. Neutrophilia, gelatinase release and microvascular leakage induced by human mast cell tryptase in a mouse model: Lack of a role of protease-activated receptor 2 (PAR2). Clin Exp Allergy 2018; 48:555-567. [PMID: 29383785 PMCID: PMC5969079 DOI: 10.1111/cea.13108] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 01/20/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Tryptase, the most abundant protease of the human mast cell, has been implicated as a key mediator of allergic inflammation that acts through activation of PAR2. OBJECTIVES To investigate the contribution of PAR2 in the pro-inflammatory actions mediated by tryptase in a mice model. METHODS We have injected recombinant human βII-tryptase into the peritoneum of PAR2-deficient and wild-type C57BL/6 mice. After 6, 12 and 24 hours, mice were killed, peritoneal lavage performed and inflammatory changes investigated. RESULTS Tryptase stimulated an increase in neutrophil numbers in the peritoneum, but responses did not differ between PAR2-deficient and wild-type mice. Heat inactivation of tryptase or pre-incubation with a selective tryptase inhibitor reduced neutrophilia, but neutrophil accumulation was not elicited with a peptide agonist of PAR2 (SLIGRL-NH2 ). Zymography indicated that tryptase stimulated the release of matrix metalloproteinases (MMP) 2 and 9 in the peritoneum of both mouse strains. Studies involving immunomagnetic isolation of neutrophils suggested that neutrophils represent the major cellular source of tryptase-induced MMP2 and MMP9. At 24 hours after tryptase injection, there was increased microvascular leakage as indicated by high levels of albumin in peritoneal lavage fluid, and this appeared to be partially abolished by heat-inactivating tryptase or addition of a protease inhibitor. There was no corresponding increase in levels of histamine or total protein. The extent of tryptase-induced microvascular leakage or gelatinase release into the peritoneum did not differ between PAR2-deficient and wild-type mice. CONCLUSIONS Our findings indicate that tryptase is a potent stimulus for neutrophil accumulation, MMP release and microvascular leakage. Although these actions required an intact catalytic site, the primary mechanism of tryptase in vivo would appear to involve processes independent of PAR2.
Collapse
Affiliation(s)
- M. E. M. S. Khedr
- Clinical and Experimental Sciences Academic UnitFaculty of MedicineUniversity of SouthamptonSouthamptonUK
- Faculty of MedicineSuez Canal UniversityIsmailiaEgypt
| | - A. M. Abdelmotelb
- Clinical and Experimental Sciences Academic UnitFaculty of MedicineUniversity of SouthamptonSouthamptonUK
- Faculty of MedicineTanta UniversityTantaEgypt
| | - S. L. F. Pender
- Clinical and Experimental Sciences Academic UnitFaculty of MedicineUniversity of SouthamptonSouthamptonUK
| | - X. Zhou
- Clinical and Experimental Sciences Academic UnitFaculty of MedicineUniversity of SouthamptonSouthamptonUK
| | - A. F. Walls
- Clinical and Experimental Sciences Academic UnitFaculty of MedicineUniversity of SouthamptonSouthamptonUK
| |
Collapse
|
9
|
Ostertag D, Annahazi A, Krueger D, Michel K, Demir IE, Ceyhan GO, Zeller F, Schemann M. Tryptase potentiates enteric nerve activation by histamine and serotonin: Relevance for the effects of mucosal biopsy supernatants from irritable bowel syndrome patients. Neurogastroenterol Motil 2017; 29. [PMID: 28374503 DOI: 10.1111/nmo.13070] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/23/2017] [Indexed: 01/02/2023]
Abstract
BACKGROUND We previously showed that mucosal biopsy supernatants from irritable bowel syndrome patients activated neurons despite low concentrations of tryptase, histamine, and serotonin which individually would not cause spike discharge. We studied the potentiating responses between these mediators on excitability of enteric neurons. METHODS Calcium-imaging was performed using the calcium-sensitive dye Fluo-4 AM in human submucous plexus preparations from 45 individuals. Histamine, serotonin, and tryptase were applied alone and in combinations to evaluate nerve activation which was assessed by analyzing increase in intracellular Ca2+ ([Ca2+ ]i ), the proportion of responding neurons and the product of both defined as Ca-neuroindex (NI). Protease activated receptor (PAR) 2 activating peptide, PAR2 antagonist and the serine protease-inhibitor FUT-175 were used to particularly investigate the role of proteases. KEY RESULTS Histamine or serotonin (1 μmol/L each) evoked only few small responses (median NI [25%/75%]: 0 [0/148]; 85 [0/705] respectively). Their combined application evoked statistically similar responses (216 [21/651]). Addition of the PAR2 activator tryptase induced a significantly higher Ca-NI (1401 [867/4075]) compared to individual application of tryptase or to coapplied histamine and serotonin. This synergistic potentiation was neither mimicked by PAR2 activating peptide nor reversed by the PAR2 antagonist GB83, but abolished by FUT-175. CONCLUSIONS & INFERENCES We observed synergistic potentiation between histamine, serotonin, and tryptase in enteric neurons, which is mediated by proteolytic activity rather than PAR2 activation. This explained neuronal activation by a cocktail of these mediators despite their low concentrations and despite a relatively small PAR2-mediated response in human submucous neurons.
Collapse
Affiliation(s)
- D Ostertag
- Human Biology, Technical University of Munich, Freising, Germany
| | - A Annahazi
- Human Biology, Technical University of Munich, Freising, Germany
| | - D Krueger
- Human Biology, Technical University of Munich, Freising, Germany
| | - K Michel
- Human Biology, Technical University of Munich, Freising, Germany
| | - I E Demir
- Department of Surgery, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - G O Ceyhan
- Department of Surgery, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - F Zeller
- Department of Surgery, Klinikum Freising, Freising, Germany
| | - M Schemann
- Human Biology, Technical University of Munich, Freising, Germany
| |
Collapse
|
10
|
Scarpelli MP, Keller S, Tran L, Palmiere C. Postmortem serum levels of IgE and mast cell tryptase in fatal asthma. Forensic Sci Int 2016; 269:113-118. [PMID: 27888720 DOI: 10.1016/j.forsciint.2016.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 09/16/2016] [Accepted: 11/01/2016] [Indexed: 12/12/2022]
Abstract
The aim of this study was to characterize the concentrations of total and specific IgE as well as mast cell-derived tryptase in postmortem serum from femoral blood and evaluate the usefulness of their determination for diagnostic purposes in cases of fatal asthma attacks. 36 autopsy cases were retrospectively selected including cases of witnessed death in asthmatic subjects, deaths in asthmatics and atopic subjects with causes of death unrelated to asthma or allergic anaphylaxis as well as deaths in non-atopic, non-allergic individuals with causes of death unrelated to asthma or allergic anaphylaxis. Initial results indicated increased postmortem serum total IgE in atopic and asthmatic individuals, irrespective of the cause of death. Conversely, increased mast cell tryptase levels were noted exclusively in fatal asthma attacks. This suggests that mast cell tryptase measurement in cases of death potentially caused by severe acute bronchial asthma may be useful for diagnostic purposes.
Collapse
Affiliation(s)
- Maria Pia Scarpelli
- Dipartimento di Sanità Pubblica e Medicina di Comunità, Università degli Studi di Verona, Policlinico G.B. Rossi, P.le L.A. Scuro 10, 37134 Verona, Italy
| | - Sanjiv Keller
- CURML, University Center of Legal Medicine, Chemin de la Vulliette 4, 1000, Lausanne 25, Switzerland
| | - Lara Tran
- CURML, University Center of Legal Medicine, Chemin de la Vulliette 4, 1000, Lausanne 25, Switzerland
| | - Cristian Palmiere
- CURML, University Center of Legal Medicine, Chemin de la Vulliette 4, 1000, Lausanne 25, Switzerland.
| |
Collapse
|
11
|
Abstract
Mast cells (MCs) play a central role in tissue homoeostasis, sensing the local environment through numerous innate cell surface receptors. This enables them to respond rapidly to perceived tissue insults with a view to initiating a co-ordinated programme of inflammation and repair. However, when the tissue insult is chronic, the ongoing release of multiple pro-inflammatory mediators, proteases, cytokines and chemokines leads to tissue damage and remodelling. In asthma, there is strong evidence of ongoing MC activation, and their mediators and cell-cell signals are capable of regulating many facets of asthma pathophysiology. This article reviews the evidence behind this.
Collapse
Affiliation(s)
- P Bradding
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, UK
| | - G Arthur
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, UK
| |
Collapse
|
12
|
Correlation of IL-18 with Tryptase in Atopic Asthma and Induction of Mast Cell Accumulation by IL-18. Mediators Inflamm 2016; 2016:4743176. [PMID: 27069315 PMCID: PMC4812453 DOI: 10.1155/2016/4743176] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 02/13/2016] [Accepted: 02/18/2016] [Indexed: 11/17/2022] Open
Abstract
Interleukin- (IL-) 18 and tryptase were previously reported to relate to asthma, but the correlation between these two potent proinflammatory molecules in asthma and their roles in mast cell accumulation remain uninvestigated. Using flow cytometric analysis technique and ovalbumin- (OVA-) sensitized mouse model, it was found that IL-18 and tryptase levels in the plasma of moderate and severe asthma were elevated, and they correlated well with each other. Tryptase and agonist peptides of protease activated receptor- (PAR-) 2 induced substantial quantity of IL-18 release. IL-18 and tryptase provoked mast cell accumulation in peritoneum of OVA-sensitized mice. OVA-sensitization increased number of IL-18 receptor (R)+ mast cells. IL-18 and tryptase induced dramatic increase in IL-18R+ mast cells and mean fluorescence intensity (MFI) of IL-18R on mast cells. Moreover, while IL-18 induced an increase in PAR-2+ mast cells in nonsensitized mice, IL-18 and tryptase provoked increases in IL-4 and thymic stromal lymphopoietin (TSLP) in the peritoneum of OVA-sensitized mice. In summary, the correlation between IL-18 and tryptase in plasma of patients with asthma indicates close interactions between them, which should be considered for development of anti-IL-18 and antitryptase therapies. Interactions between IL-18 and tryptase may contribute to mast cell recruitment in asthma.
Collapse
|
13
|
Protease inhibitor reduces airway response and underlying inflammation in cockroach allergen-induced murine model. Inflammation 2015; 38:672-82. [PMID: 25052477 DOI: 10.1007/s10753-014-9976-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Protease(s) enhances airway inflammation and allergic cascade. In the present study, effect of a serine protease inhibitor was evaluated in mouse model of airway disease. Mice were sensitized with cockroach extract (CE) or Per a 10 and treated with 4-(2-aminoethyl) benzenesulfonyl fluoride hydrochloride (AEBSF) 1 h before or after challenge to measure airway response. Mice were euthanized to collect bronchoalveolar lavage fluid (BALF), blood, and lung to evaluate inflammation. AEBSF treatment significantly reduced the AHR in allergen-challenged mice in dose-dependent manner (p≤ 0.01). IgE (p≤0.05) and Th2 cytokines (p≤0.05) were significantly reduced in treated mice. AEBSF treatment lowered total cell (p≤0.05), eosinophil (p≤0.05), and neutrophil (p≤0.05) in BALF and lung tissue. Oxidative stress parameters were impaired on treatment in allergen-challenged mice (p≤0.05). AEBSF had therapeutic effect in allergen-induced airway resistance and underling inflammation and had potential for combination or as add-on therapy for respiratory diseases.
Collapse
|
14
|
Li J, Jubair S, Levick SP, Janicki JS. THE AUTOCRINE ROLE OF TRYPTASE IN PRESSURE OVERLOAD-INDUCED MAST CELL ACTIVATION, CHYMASE RELEASE AND CARDIAC FIBROSIS. ACTA ACUST UNITED AC 2015; 10:16-23. [PMID: 26722642 DOI: 10.1016/j.ijcme.2015.11.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Cardiac mast cell (MC) proteases, chymase and tryptase, increase proliferation and collagen synthesis in cultured cardiac fibroblasts. However, the question as to why preventing individually the actions of either protease prevents fibrosis when both are released upon MC activation remains unanswered. Since tryptase has the ability to activate MCs in noncardiac tissues via the protease-activated receptor-2 (PAR-2), there is the possibility that its, in vivo, fibrotic role is due to its ability to induce MC degranulation thereby amplifying the release of chymase. METHODS This study sought to delineate the interactions between tryptase and chymase in myocardial remodeling secondary to transverse aortic constriction (TAC) for 5 wks in male Sprague Dawley rats untreated or treated with either the tryptase inhibitor, nafamostat mesilate or MC membrane stabilizing drug, nedocromil (n=6/group). In addition, ventricular slices from 6 rat hearts were incubated with tryptase, tryptase plus nafamostat mesilate or chymostatin for 24 h. RESULTS AND CONCLUSION The results indicate the presence of PAR-2 on MCs and that tryptase inhibition and nedocromil prevented TAC-induced fibrosis and increases in MC density, activation, and chymase release. Tryptase also significantly increased chymase concentration in ventricular tissue culture media, which was prevented by the tryptase inhibitor. Hydroxyproline concentration in culture media was significantly increased with tryptase incubation as compared to the control group and the tryptase group incubated with nafamostat mesilate or chymostatin. We conclude that tryptase contributes to TAC-induced cardiac fibrosis primarily via activation of MCs and the amplified release of chymase.
Collapse
Affiliation(s)
- Jianping Li
- Cell Biology and Anatomy, School of Medicine, University of South Carolina Columbia, SC 29208, USA
| | - Shaiban Jubair
- Cell Biology and Anatomy, School of Medicine, University of South Carolina Columbia, SC 29208, USA
| | - Scott P Levick
- Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, WI 53226, USA ; Cardiovascular Center, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Joseph S Janicki
- Cell Biology and Anatomy, School of Medicine, University of South Carolina Columbia, SC 29208, USA
| |
Collapse
|
15
|
Abdelmotelb AM, Rose-Zerilli MJ, Barton SJ, Holgate ST, Walls AF, Holloway JW. Alpha-tryptase gene variation is associated with levels of circulating IgE and lung function in asthma. Clin Exp Allergy 2015; 44:822-30. [PMID: 24372627 PMCID: PMC4282335 DOI: 10.1111/cea.12259] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 11/20/2013] [Accepted: 11/27/2013] [Indexed: 12/31/2022]
Abstract
Background Tryptase, a major secretory product of human mast cells has been implicated as a key mediator of allergic inflammation. Genetic variation in the tryptases is extensive, and α-tryptase, an allelic variant of the more extensively studied β-tryptase, is absent in substantial numbers of the general population. The degree to which α-tryptase expression may be associated with asthma has not been studied. We have investigated the α-tryptase gene copy number variation and its potential associations with phenotypes of asthma. Objectives Caucasian families (n = 341) with at least two asthmatic siblings (n = 1350) were genotyped for the α-tryptase alleles, using high-resolution melting assays. Standards for the possible α-/β-tryptase ratios were constructed by cloning α-and β-tryptase PCR products to generate artificial templates. Association analysis of asthma affection status and related phenotypes [total and allergen-specific serum IgE, bronchial hyperresponsiveness to methacholine, forced expiratory volume in 1s (FEV1) and atopy and asthma severity scores] was undertaken using family-based association tests (FBAT). Results Four consistent melting patterns for the α-tryptase genotype were identified with alleles carrying null, one or two copies of the α-tryptase allele. Possessing one copy of α-tryptase was significantly associated with lower serum levels of total and dust mite-specific IgE levels and higher FEV1 measurements, while two copies were related to higher serum concentrations of total and dust mite-specific IgE and greater atopy severity scores. Conclusions and Clinical Relevance Associations of α-tryptase copy number with serum IgE levels, atopy scores and bronchial function may reflect roles for tryptases in regulating IgE production and other processes in asthma.
Collapse
Affiliation(s)
- A M Abdelmotelb
- Clinical and Experimental Sciences Unit, Faculty of Medicine, University of Southampton, Southampton, UK; Faculty of Medicine, Tanta University, Tanta, Egypt
| | | | | | | | | | | |
Collapse
|
16
|
Antoniak S, Mackman N. Coagulation, protease-activated receptors, and viral myocarditis. J Cardiovasc Transl Res 2013; 7:203-11. [PMID: 24203054 DOI: 10.1007/s12265-013-9515-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/16/2013] [Indexed: 12/29/2022]
Abstract
The coagulation protease cascade plays an essential role in hemostasis. In addition, a clot contributes to host defense by limiting the spread of pathogens. Coagulation proteases induce intracellular signaling by cleavage of cell surface receptors called protease-activated receptors (PARs). These receptors allow cells to sense changes in the extracellular environment, such as infection. Viruses activate the coagulation cascade by inducing tissue factor expression and by disrupting the endothelium. Virus infection of the heart can cause myocarditis, cardiac remodeling, and heart failure. A recent study using a mouse model have shown that tissue factor, thrombin, and PAR-1 signaling all positively regulate the innate immune during viral myocarditis. In contrast, PAR-2 signaling was found to inhibit interferon-β expression and the innate immune response. These observations suggest that anticoagulants may impair the innate immune response to viral infection and that inhibition of PAR-2 may be a new strategy to reduce viral myocarditis.
Collapse
Affiliation(s)
- Silvio Antoniak
- Division of Hematology and Oncology, Department of Medicine, UNC McAllister Heart Institute, University of North Carolina at Chapel Hill, 98 Manning Drive, Campus Box 7035, Chapel Hill, NC, 27599, USA,
| | | |
Collapse
|
17
|
Kim HY, Goo JH, Joo YA, Lee HY, Lee SM, Oh CT, Ahn SM, Kim NH, Hwang JS. Impact on inflammation and recovery of skin barrier by nordihydroguaiaretic Acid as a protease-activated receptor 2 antagonist. Biomol Ther (Seoul) 2013; 20:463-9. [PMID: 24009835 PMCID: PMC3762283 DOI: 10.4062/biomolther.2012.20.5.463] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 07/11/2012] [Accepted: 07/17/2012] [Indexed: 12/26/2022] Open
Abstract
Atopic dermatitis is a chronic, inflammatory disease of the skin with increased transepidermal water loss. Both an abnormal inflammatory response and a defective skin barrier are known to be involved in the pathogenesis of atopic dermatitis. Protease activated receptor 2 (PAR2) belongs to a family of G-protein coupled receptors and is activated by both trypsin and a specific agonist peptide, SLIGKV-NH2. PAR2 is expressed in suprabasal layers of the epidermis and regulates inflammatory responses and barrier homeostasis. In this study, we show that nordihydroguaiaretic acid (NDGA) inhibits the PAR2-mediated signal pathway and plays a role in skin barrier recovery in atopic dermatitis. Specifically, NDGA reduces the mobilization of intracellular Ca(2+) in HaCaT keratinocytes by down-regulating inflammatory mediators, such as interleukin-8, thymus and activation-regulated chemokine and intercellular cell adhesion molecule-1 in HaCaT keratinocytes. Also, NDGA decreases the protein expression of involucrin, a differentiation maker of keratinocyte, in both HaCaT keratinocytes and normal human epidermal keratinocytes. We examined NDGA-recovered skin barrier in atopic dermatitis by using an oxazolone-induced atopic dermatitis model in hairless mice. Topical application of NDGA produced an increase in transepidermal water loss recovery and a decrease in serum IgE level, without weight loss. Accordingly, we suggest that NDGA acts as a PAR2 antagonist and may be a possible therapeutic agent for atopic dermatitis.
Collapse
Affiliation(s)
- Hyo Young Kim
- Department of Genetic Engineering, College of Life Science and Skin Biotechnology Center, Kyung Hee University, Yongin 446-701, Republic of Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Liang G, Aldous S, Merriman G, Levell J, Pribish J, Cairns J, Chen X, Maignan S, Mathieu M, Tsay J, Sides K, Rebello S, Whitely B, Morize I, Pauls HW. Structure-based library design and the discovery of a potent and selective mast cell β-tryptase inhibitor as an oral therapeutic agent. Bioorg Med Chem Lett 2012; 22:1049-54. [DOI: 10.1016/j.bmcl.2011.11.119] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 11/25/2011] [Accepted: 11/28/2011] [Indexed: 10/14/2022]
|
19
|
Zizzi A, Aspriello SD, Rubini C, Goteri G. Peri-implant diseases and host inflammatory response involving mast cells: a review. Int J Immunopathol Pharmacol 2011; 24:557-66. [PMID: 21978688 DOI: 10.1177/039463201102400302] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Mast cells (MCs) are motile granule-containing cells that originate from bone marrow pluripotential haematopoietic cells, circulate in blood and extravasate in tissues where they play an important role in inflammation, host defense and tissue repair. We herein review the English literature over the past twenty years concerning the biology and function of MCs with particular focus on their role in the inflammatory process in dental implant failure due to osseointegration absence or to peri-implantitis. Due to immunological or non-immunological stimulation, in a few minutes MCs release prestored granule-associated mediators into the extracellular environment promoting pro-/anti-inflammatory events/response. MCs can either protect the host by activating defense mechanisms and initiating tissue repair and osseointegration if their function is transient, or lead to considerable tissue damage if it is inappropriate and continuous leading to osseointegration absence or peri-implantitis. We hypothesize that administration of histamine receptor antagonists, serine protease inhibitors and MC preformed mediator release inhibitors before and after implantation could represent novel therapeutic strategies to improve the osseointegration, the functionality and longevity of implants or prevent and treat peri-implant inflammatory conditions.
Collapse
|
20
|
Summers SA, Chan J, Gan PY, Dewage L, Nozaki Y, Steinmetz OM, Nikolic-Paterson DJ, Kitching AR, Holdsworth SR. Mast cells mediate acute kidney injury through the production of TNF. J Am Soc Nephrol 2011; 22:2226-36. [PMID: 22021718 DOI: 10.1681/asn.2011020182] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Leukocyte recruitment contributes to acute kidney injury (AKI), but the mechanisms by which leukocytes promote injury are not completely understood. The degranulation of mast cells releases inflammatory molecules, including TNF, but whether these cells participate in the pathogenesis of AKI is unknown. Here, we induced AKI with cisplatin in mast cell-deficient and wild-type mice. Compared with wild-type mice, deficiency of mast cells attenuated renal injury, reduced serum levels of TNF, and reduced recruitment of leukocytes to the inflamed kidney. Mast cell-deficient mice also exhibited significantly lower intrarenal expression of leukocyte chemoattractants. Mast cell-deficient mice reconstituted with mast cells from wild-type mice exhibited similar cisplastin-induced renal damage and serum levels of TNF as wild-type mice. In contrast, mast cell-deficient mice reconstituted with mast cells from TNF-deficient mice continued to demonstrate significant attenuation of cisplatin-induced renal injury. Furthermore, the mast-cell stabilizer sodium chromoglycate also significantly abrogated renal injury in this model of AKI. Taken together, these results suggest that mast cells mediate AKI through the production of TNF.
Collapse
Affiliation(s)
- Shaun A Summers
- Centre for Inflammatory Diseases, Department of Medicine, Monash University, 246 Clayton Road, Clayton, VIC 3168, Australia
| | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Mortaz E, Folkerts G, Redegeld F. Mast cells and COPD. Pulm Pharmacol Ther 2011; 24:367-72. [PMID: 21463700 DOI: 10.1016/j.pupt.2011.03.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 03/24/2011] [Accepted: 03/25/2011] [Indexed: 12/17/2022]
Abstract
The pathogenesis of chronic obstructive pulmonary disease (COPD) is based on the innate and adaptive inflammatory immune response to the inhalation of toxic particles and gases. Although tobacco smoking is the primary cause of this inhalation injury, many other environmental and occupational exposures contribute to the pathology of COPD. The immune inflammatory changes associated with COPD are linked to a tissue-repair and -remodeling process that increases mucus production and causes emphysematous destruction of the gas-exchanging surface of the lung. The common form of emphysema observed in smokers begins in the respiratory bronchioles near the thickened and narrowed small bronchioles that become the major site of obstruction in COPD. The inflamed airways of COPD patients contain several inflammatory cells including neutrophils, macrophages, T lymphocytes, and dendritic cells. The relative contribution of mast cells to airway injury and remodeling is not well documented. In this review, an overview is given on the possible role of mast cells and their mediators in the pathogenesis of COPD. Activation of mast cells and mast cell signaling in response to exposure to cigarette smoke is further discussed.
Collapse
Affiliation(s)
- Esmaeil Mortaz
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | | | | |
Collapse
|
22
|
Mast cell proteases as protective and inflammatory mediators. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 716:212-34. [PMID: 21713659 DOI: 10.1007/978-1-4419-9533-9_12] [Citation(s) in RCA: 121] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Proteases are the most abundant class of proteins produced by mast cells. Many of these are stored in membrane-enclosed intracellular granules until liberated by degranulating stimuli, which include cross-linking of high affinity IgE receptor F(c)εRI by IgE bound to multivalent allergen. Understanding and separating the functions of the proteases is important because expression differs among mast cells in different tissue locations. Differences between laboratory animals and humans in protease expression also influence the degree of confidence with which results obtained in animal models of mast cell function can be extrapolated to humans. The inflammatory potential of mast cell proteases was the first aspect of their biology to be explored and has received the most attention, in part because some of them, notably tryptases and chymases, are biomarkers of local and systemic mast cell degranulation and anaphylaxis. Although some of the proteases indeed augment allergic inflammation and are potential targets for inhibition to treat asthma and related allergic disorders, they are protective and even anti-inflammatory in some settings. For example, mast cell tryptases may protect from serious bacterial lung infections and may limit the "rubor" component of inflammation caused by vasodilating neuropeptides in the skin. Chymases help to maintain intestinal barrier function and to expel parasitic worms and may support blood pressure during anaphylaxis by generating angiotensin II. In other life-or-death examples, carboxypeptidase A3 and other mast cell peptidases limit systemic toxicity of endogenous peptideslike endothelin and neurotensin during septic peritonitis and inactivate venom-associated peptides. On the other hand, mast cell peptidase-mediated destruction of protective cytokines, like IL-6, can enhance mortality from sepsis. Peptidases released from mast cells also influence nonmast cell proteases, such as by activating matrix metalloproteinase cascades, which are important in responses to infection and resolution of tissue injury. Overall, mast cell proteases have a variety of roles, inflammatory and anti-inflammatory, protective and deleterious, in keeping with the increasingly well-appreciated contributions of mast cells in allergy, tissue homeostasis and innate immunity.
Collapse
|
23
|
Bachelet I, Munitz A, Levi-Schaffer F. Tryptase as an inflammatory marker in allergic disease and asthma. Expert Rev Clin Immunol 2010; 1:63-73. [PMID: 20477655 DOI: 10.1586/1744666x.1.1.63] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Asthma is a chronic inflammatory disease of the airways, varying from occasional episodes of wheezing and shortness of breath, to an irreversible, life-threatening obstructive disease. While many cases are managed with relative ease, others do not respond to the traditional inhaled therapy or even to oral glucocorticosteroids. Although it cannot be cured as yet, asthma can be controlled if properly diagnosed. Usually, functional clinical parameters form the basis for estimation of the disease severity. In addition, the growing database of cytokine and mediator profiles have allowed their exploitation as molecular markers for processes underlying airway inflammation in asthma. Tryptase is a potent and versatile mediator in allergic inflammation, orchestrating both acute and chronic events by acting on a vast array of cells and tissue components. For more than a decade, tryptase has been used as a marker for allergic inflammation in asthma as well as in a variety of other airway diseases. In this review, the current advantages and disadvantages of the use of tryptase as an inflammatory marker in asthma will be discussed.
Collapse
Affiliation(s)
- Ido Bachelet
- The Hebrew University of Jerusalem, Department of Pharmacology, Jerusalem 91120, Israel.
| | | | | |
Collapse
|
24
|
Malaviya R, Laskin DL, Malaviya R. Janus kinase-3 dependent inflammatory responses in allergic asthma. Int Immunopharmacol 2010; 10:829-36. [PMID: 20430118 DOI: 10.1016/j.intimp.2010.04.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Revised: 03/25/2010] [Accepted: 04/20/2010] [Indexed: 12/14/2022]
Abstract
Allergic asthma is a chronic inflammatory condition of the lung characterized by reversible airway obstruction, high serum immunoglobulin (Ig) E levels, and chronic airway inflammation. A number of cells including mast cells, T cells, macrophages and dendritic cells play a role in the pathogenesis of the disease. Janus kinase (JAK)-3, a non-receptor protein tyrosine kinase, traditionally known to mediate cytokine signaling, also regulates functional responses of these cells. In this review the role of JAK-3 in regulating various pathogenic processes in allergic asthma is discussed. We propose that targeting JAK-3 is a rationale approach to control the inflammatory responses of multiple cell types responsible for the pathogenesis of allergic asthma.
Collapse
Affiliation(s)
- Rama Malaviya
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ 08854, USA.
| | | | | |
Collapse
|
25
|
Lam DK, Schmidt BL. Serine proteases and protease-activated receptor 2-dependent allodynia: a novel cancer pain pathway. Pain 2010; 149:263-272. [PMID: 20189717 DOI: 10.1016/j.pain.2010.02.010] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Revised: 02/05/2010] [Accepted: 02/05/2010] [Indexed: 10/19/2022]
Abstract
Mediators involved in the generation of pain in patients with cancer are poorly understood. Using a combined molecular, pharmacologic, behavioral, and genetic approach, we have identified a novel mechanism of cancer-dependent allodynia induced by protease-activated receptor 2 (PAR2). Here we show that human head and neck carcinoma cells have increased levels of proteolytic activity compared to normal human cell controls. Supernatant from human carcinoma cells, but not controls, caused marked and prolonged mechanical allodynia in mice, when administered into the hindpaw. This nociceptive effect was abolished by serine protease inhibition, diminished by mast cell depletion and absent in PAR2-deficient mice. In addition, non-contact co-culture of trigeminal ganglion neurons with human head and neck carcinoma cells increased the proportion of neurons that exhibited PAR2-immunoreactivity. Our results point to a direct role for serine proteases and their receptor in the pathogenesis of cancer pain. This previously unrecognized cancer pain pathway has important therapeutic implications wherein serine protease inhibitors and PAR2 antagonists may be useful for the treatment of cancer pain.
Collapse
Affiliation(s)
- D K Lam
- Department of Oral and Maxillofacial Surgery, University of California - San Francisco, San Francisco, CA, USA
| | | |
Collapse
|
26
|
Induction of microvascular leakage and histamine release by promutoxin, an Arg49 phospholipase A2. Toxicon 2009; 55:888-96. [PMID: 20036273 DOI: 10.1016/j.toxicon.2009.12.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2009] [Revised: 12/14/2009] [Accepted: 12/17/2009] [Indexed: 11/22/2022]
Abstract
It has been recognized that phospholipase A(2) (PLA(2)) is a crucial factor of snake venom induced inflammation. Recently, promutoxin, a novel member of minor subgroup of snake venom PLA(2) (R49 PLA(2)) has been characterized in our laboratory, but its roles in induction of inflammation remain uninvestigated. Using highly purified promutoxin, we found this enzymatically inactive PLA(2) provoked a dose-dependent increase in microvascular leakage in the skin of rats. Pretreatment of rats with compound 48/80 diminished promutoxin-induced skin reaction and reduced mast cell numbers in rats. Cyproheptadine, terfenadine, Ginkgolide B and heparin inhibited promutoxin elicited microvascular leakage when they were co-injected with the stimulus to rat skin. Moreover, promutoxin was found to induce histamine release from human colon, lung and tonsil mast cells, and both metabolic inhibitors and pertussis toxin were capable of inhibiting promutoxin elicited histamine release. Provocation of microvascular leakage and mast cell activation by promutoxin suggests further that snake venom induced inflammation is related to mast cell activation and certain anti-inflammatory drugs could be therapeutic effective in treating snake wound.
Collapse
|
27
|
Trivedi NN, Caughey GH. Mast cell peptidases: chameleons of innate immunity and host defense. Am J Respir Cell Mol Biol 2009; 42:257-67. [PMID: 19933375 DOI: 10.1165/rcmb.2009-0324rt] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Mast cells make and secrete an abundance of peptidases, which are stored in such large amounts in granules that they comprise a high fraction of all cellular protein. Perhaps no other immune cell is so generously endowed with peptidases. For many years after the main peptidases were first described, they were best known as markers of degranulation, for they are released locally in response to mast cell stimulation and can be distributed systemically and detected in blood. The principal peptidases are tryptases, chymases, carboxypeptidase A3, and dipeptidylpeptidase I (cathepsin C). Numerous studies suggest that these enzymes are important and even critical for host defense and homeostasis. Endogenous and allergen or pathogen-associated targets have been identified. Belying the narrow notion of peptidases as proinflammatory, several of the peptidases limit inflammation and toxicity of endogenous peptides and venoms. The peptidases are interdependent, so that absence or inactivity of one enzyme can alter levels and activity of others. Mammalian mast cell peptidases--chymases and tryptases especially--vary remarkably in number, expression, biophysical properties, and specificity, perhaps because they hyper-evolved under pressure from the very pathogens they help to repel. Tryptase and chymase involvement in some pathologies stimulated development of therapeutic inhibitors for use in asthma, lung fibrosis, pulmonary hypertension, ulcerative colitis, and cardiovascular diseases. While animal studies support the potential for mast cell peptidase inhibitors to mitigate certain diseases, other studies, as in mice lacking selected peptidases, predict roles in defense against bacteria and parasites and that systemic inactivation may impair host defense.
Collapse
Affiliation(s)
- Neil N Trivedi
- Section of Pulmonary and Critical Care Medicine, Medicine Service, Veterans Affairs Medical Center, Mailstop 111-D, 4150 Clement Street, San Francisco, CA 94121, USA
| | | |
Collapse
|
28
|
Qiao L, Zhang H, Wu S, He S. Downregulation of protease activated receptor expression and cytokine production in P815 cells by RNA interference. BMC Cell Biol 2009; 10:62. [PMID: 19732468 PMCID: PMC2751739 DOI: 10.1186/1471-2121-10-62] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 09/07/2009] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Protease-activated receptors (PAR) are seven transmembrane G-coupled receptors comprising four genes (PAR-1 approximately PAR-4). Mast cell has been identified to be able to express PARs and release an array of cytokines upon activation. Recently, it was reported that interleukin (IL)-12 could regulate the expression of PARs in mast cells, and tryptase could induce IL-4 and IL-6 release from mast cells. In order to further investigate the issues, RNA interference (RNAi) technique was employed and small interfering RNAs (siRNA) of PARs were transfected in P815 cells. RESULTS The results showed that siRNAs for PAR-1, PAR-2 and PAR-4 significantly downregulated expression of PAR-1, PAR-2 and PAR-4 mRNAs and proteins in P815 cells at 24, 48 and 72 h following transfection. siRNA PAR-1.2 and siRNA PAR-4.2 significantly reduced IL-12 induced upregulation of PAR-1 and PAR-4 expression, respectively when P815 cells were transfected with them for 48 h. siRNA PAR-2.3 blocked IL-12 induced downregulation of PAR-2 expression on both mRNA and protein levels. It was also observed that siRNA PAR-2.3 and siRNA PAR-1.2 reduced trypsin induced IL-4 release by approximately 92.6% and 65.3%, and SLIGKV-NH2 induced IL-4 release by 82.1% and 60.1%, respectively. Similarly, siRNA PAR-2.3 eliminated tryptase-induced IL-4 release by 75.3%, and siRNA PAR-1.2 diminished SFLLR-NH2 induced IL-4 release by 79.3%. However, siRNA PAR-1.2, siRNA PAR-2.3 and siRNA PAR-4.3 at 10 nM did not show any effect on tryptase-induced IL-6 release from P815 cells. CONCLUSION In conclusion, siRNAs of PARs can modulate PAR expression and PAR related cytokine production in mast cells, confirming that PARs are likely to play a role in allergic reactions.
Collapse
Affiliation(s)
- Liya Qiao
- Allergy and Inflammation Research Institute, Shantou University Medical College, 22 Xin-ling Road, Shantou, Guangdong 515041, PR China
| | - Huiyun Zhang
- Allergy and Inflammation Research Institute, Shantou University Medical College, 22 Xin-ling Road, Shantou, Guangdong 515041, PR China
| | - Shandong Wu
- Zhejiang University Medical College, Science and Research Building, Block C, Hangzhou 310013, PR China
| | - Shaoheng He
- Allergy and Inflammation Research Institute, Shantou University Medical College, 22 Xin-ling Road, Shantou, Guangdong 515041, PR China
- Clinical Research Center, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, PR China
| |
Collapse
|
29
|
Experimental activation of mast cells and their pharmacological modulation. METHODS IN MOLECULAR MEDICINE 2008. [PMID: 18612619 DOI: 10.1007/978-1-59745-366-0_26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
The activation of mast cells is of pivotal importance in the pathogenesis of allergic conditions. Mast cell activation can provoke rapid increases in microvascular permeability, induce bronchoconstriction after blood flow, stimulate the recruitment and activation of other inflammatory cells, and has come to be associated with the processes of tissue remodeling and fibrosis. Such changes may be mediated by the release of a range of potent mediators of inflammation: preformed in secretory granules, or newly generated, or both. There are major differences in the responsiveness to various stimuli and to pharmacological agents for mast cells from different body compartments. A method is presented here for the purification of mast cells from enzymatically dispersed human tissues. The methods described for the experimental activation of mast cells can be readily adapted to studies with cell lines or mast cells obtained through long-term culture.
Collapse
|
30
|
Abstract
Although there is much circumstantial evidence implicating eosinophils as major orchestrators in the pathophysiology of asthma, recent studies have cast doubt on their importance. Not only does anti-interleukin-5 treatment not alter the course of the disease, but some patients with asthma do not have eosinophils in their airways, whereas patients with eosinophilic bronchitis exhibit a florid tissue eosinophilia but do not have asthma. In contrast, mast cells are found in all airways and localize specifically to key tissue structures such as the submucosal glands and airway smooth muscle within asthmatic bronchi, irrespective of disease severity or phenotype. Here they are activated and interact exclusively with these structural cells via adhesive pathways and through the release of soluble mediators acting across the distance of only a few microns. The location of mast cells within the airway smooth muscle bundles seems particularly important for the development and propagation of asthma, perhaps occurring in response to, and then serving to aggravate, an underlying abnormality in asthmatic airway smooth muscle function. Targeting this mast cell-airway smooth muscle interaction in asthma offers exciting prospects for the treatment of this common disease.
Collapse
|
31
|
|
32
|
Abstract
Two types of mast cells, MC(T) and MC(TC), exist in humans. MC(T) and MC(TC) are different in their granular neutral proteases, tissue localizations, and functions. This article describes the differences between the cutaneous mast cell receptors.
Collapse
Affiliation(s)
- Michihiro Hide
- Department of Dermatology, Programs for Biomedical Research, Division of Molecular Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
| | | | | |
Collapse
|
33
|
Zhang H, Yang X, Yang H, Zhang Z, Lin Q, Zheng Y, Chen S, Yang P, He S. Modulation of mast cell proteinase-activated receptor expression and IL-4 release by IL-12. Immunol Cell Biol 2007; 85:558-66. [PMID: 17592496 DOI: 10.1038/sj.icb.7100085] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It has been recognized that protease-activated receptors (PARs), interleukin (IL)-4 and IL-6 are involved in the pathogenesis of allergic diseases, and that IL-12 plays a role in adaptive immune response. However, little is known of the effect of IL-12 on protease-induced cytokine release from mast cells. In the present study, we examined potential influence of IL-12 on mast cell PAR expression and IL-4 and IL-6 release. The results showed that IL-12 downregulated the expression of PAR-2 and upregulated expression of PAR-4 on P815 cells. It also downregulated expression of PAR-2 mRNA, and upregulated expression of PAR-1, PAR-3 and PAR-4 mRNAs. However, IL-12 enhanced trypsin- and tryptase-induced PAR-2 and PAR-2 mRNA expression. It was observed that IL-12 induced release of IL-4, but reduced trypsin- and tryptase-stimulated IL-4 secretion from P815 cells. PD98059, U0126 and LY294002 not only abolished IL-12-induced IL-4 release but also inhibited IL-12-induced phosphorylation of extracellular signal-regulated kinase and Akt. In conclusion, IL-12 may serve as a regulator in keeping the balance of Th1 and Th2 cytokine production in allergic inflammation.
Collapse
Affiliation(s)
- Huiyun Zhang
- The Key Immunopharmacology Laboratory of Guangdong Province, Allergy and Inflammation Research Institute, Shantou University Medical College, Shantou, China
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Sokolova E, Reiser G. A novel therapeutic target in various lung diseases: Airway proteases and protease-activated receptors. Pharmacol Ther 2007; 115:70-83. [PMID: 17532472 DOI: 10.1016/j.pharmthera.2007.04.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Accepted: 04/05/2007] [Indexed: 10/23/2022]
Abstract
Protease-activated receptors (PAR), which are G protein-coupled receptors, have 4 members, PAR-1 to PAR-4. PARs are activated by proteolysis of a peptide bond at the N-terminal domain of the receptor. PARs are widely distributed throughout the airways. Their activity is modulated by airway proteases of endogenous and exogenous origin, which can either activate or disable the receptors. The regulation of PAR activity by proteases is important under pathological conditions when the activity of proteases is increased. Moreover, various inflammatory mediators, such as cytokines, growth factors, or prostanoids, alter the PAR expression level. Elevated PAR levels are observed in various lung disorders, and their significance in the development of pathological situations in the lung is currently intensively investigated. Consequences of PAR activation can be either beneficial or deleterious, depending on the PAR subtype. PAR-1 has been shown to be an important player in the development of pulmonary fibrosis. Thus, PAR-1 represents an exciting target for clinical intervention in fibrotic diseases. PAR-2 contributes to allergic airway inflammation. However, the question whether the impact of PAR-2 is beneficial or deleterious is still under intensive discussion. Therefore, precise information concerning the participation of PAR-2 in various lesions is required. Moreover, it is necessary to generate selective PAR- and organ-targeted approaches for treating the diseases. A thorough understanding of PAR-induced cellular events and the consequences of receptor blockade may help in the development of novel therapeutic strategies targeted to prevent lung destruction and to avoid deterioration of conditions of patients with inflammatory or fibrotic lung diseases.
Collapse
Affiliation(s)
- Elena Sokolova
- Otto-von-Guericke-Universität Magdeburg, Medizinische Fakultät, Zentrum für Biochemie und Molekularbiologie, Institut für Neurobiochemie, Leipziger Strasse 44, D-39120, Magdeburg, Germany
| | | |
Collapse
|
35
|
Paesen GC, Siebold C, Harlos K, Peacey MF, Nuttall PA, Stuart DI. A tick protein with a modified Kunitz fold inhibits human tryptase. J Mol Biol 2007; 368:1172-86. [PMID: 17391695 DOI: 10.1016/j.jmb.2007.03.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Revised: 03/03/2007] [Accepted: 03/07/2007] [Indexed: 11/24/2022]
Abstract
TdPI, a tick salivary gland product related to Kunitz/BPTI proteins is a potent inhibitor of human beta-tryptase. Kinetic assays suggest that three of the four catalytic sites of tryptase are blocked by TdPI, and that the inhibition of one of these involves a peptide flanking the Kunitz head. In the course of the inhibition, tryptase cleaves TdPI at several positions. Crystal structures of the TdPI head, on its own and in complex with trypsin, reveal features that are not found in classical Kunitz/BPTI proteins and suggest the mode of interaction with tryptase. The loop of TdPI connecting the beta-sheet with the C-terminal alpha-helix is shortened, the disulphide-bridge pattern altered and N and C termini separated to produce a highly pointed molecule capable of penetrating the cramped active sites of tryptase. TdPI accumulates in the cytosolic granules of mast cells, presumably suppressing inflammation in the host animal's skin by tryptase inhibition.
Collapse
|
36
|
Freund-Michel V, Frossard N. Inflammatory conditions increase expression of protease-activated receptor-2 by human airway smooth muscle cells in culture. Fundam Clin Pharmacol 2006; 20:351-7. [PMID: 16867018 DOI: 10.1111/j.1472-8206.2006.00418.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The protease-activated receptor-2 (PAR-2) has been implicated in airway inflammation and bronchial hyperresponsiveness. We wondered whether inflammatory conditions may upregulate PAR-2 expression by the human airway smooth muscle. To do so, we treated human airway smooth muscle cells (HASMC) in primary culture with interleukin-1beta (IL-1beta), a pro-inflammatory and asthma-associated cytokine. Cells were starved for 24 h and incubated with or without IL-1beta. Online fluorescent polymerase chain reaction after reverse transcription quantified PAR-2 mRNA, and Western blotting measured PAR-2 protein expression. PAR-2 was constitutively expressed by HASMC in primary culture, and IL-1beta (10 U/mL) time dependently elevated PAR-2 mRNA with a maximum of 4.7-fold after 1.5 h (P < 0.01), and PAR-2 protein expression with a maximum of 1.5-fold after 24 h (P < 0.01). The concentration dependence of the IL-1beta effect (0.1-30 U/mL) confirmed a maximal increase of PAR-2 expression at 10 U/mL. Our study clearly shows that IL-1beta upregulates PAR-2 mRNA and protein expression by HASMC in culture. This increased expression of PAR-2 in inflammatory conditions may have functional consequences in the bronchial dysfunction of asthmatic airways.
Collapse
Affiliation(s)
- Véronique Freund-Michel
- EA 3771 Inflammation and Environment in Asthma, Faculté de Pharmacie, Université Louis Pasteur-Strasbourg I, Illkirch, France.
| | | |
Collapse
|
37
|
Abstract
Mast cells play a central role in innate immunity and in orchestrating the asthmatic response. Current medication relies on beta-agonists to relieve bronchoconstriction and steroids to reduce inflammation. However, recently drugs such as leukotriene-receptor antagonists and anti-immunoglobulin E have come on to the market. In this paper, a number of potential targets for modifying mast cell activation in asthma are reviewed. Some are already under study, including clinical trials (eg, tryptase inhibitors); others are more speculative (eg, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase activity). In each case, where data are available, the action of the agents on human lung mast cells is described.
Collapse
Affiliation(s)
- Madeleine Ennis
- Respiratory Research Group, School of Medicine and Dentistry, The Queen's University of Belfast, Institute of Clinical Science, Grosvenor Road, Belfast BT12 6BJ, UK.
| |
Collapse
|
38
|
Wang H, Zheng Y, He S. Induction of release and up-regulated gene expression of interleukin (IL)-8 in A549 cells by serine proteinases. BMC Cell Biol 2006; 7:22. [PMID: 16696869 PMCID: PMC1489934 DOI: 10.1186/1471-2121-7-22] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2005] [Accepted: 05/15/2006] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Hypersecretion of cytokines and serine proteinases has been observed in asthma. Since protease-activated receptors (PARs) are receptors of several serine proteinases and airway epithelial cells are a major source of cytokines, the influence of serine proteinases and PARs on interleukin (IL)-8 secretion and gene expression in cultured A549 cells was examined. RESULTS A549 cells express all four PARs at both protein and mRNA levels as assessed by flow cytometry, immunofluorescence microscopy and reverse transcription polymerase chain reaction (PCR). Thrombin, tryptase, elastase and trypsin induce a up to 8, 4.3, 4.4 and 5.1 fold increase in IL-8 release from A549 cells, respectively following 16 h incubation period. The thrombin, elastase and trypsin induced secretion of IL-8 can be abolished by their specific inhibitors. Agonist peptides of PAR-1, PAR-2 and PAR-4 stimulate up to 15.6, 6.6 and 3.5 fold increase in IL-8 secretion, respectively. Real time PCR shows that IL-8 mRNA is up-regulated by the serine proteinases tested and by agonist peptides of PAR-1 and PAR-2. CONCLUSION The proteinases, possibly through activation of PARs can stimulate IL-8 release from A549 cells, suggesting that they are likely to contribute to IL-8 related airway inflammatory disorders in man.
Collapse
Affiliation(s)
- Haiyan Wang
- Allergy and Inflammation Research Institute, the Key Immunopharmacology Laboratory of Guangdong Province, Shantou University Medical College, Shantou 515031, China
| | - Yanshan Zheng
- Allergy and Inflammation Research Institute, the Key Immunopharmacology Laboratory of Guangdong Province, Shantou University Medical College, Shantou 515031, China
| | - Shaoheng He
- Allergy and Inflammation Research Institute, the Key Immunopharmacology Laboratory of Guangdong Province, Shantou University Medical College, Shantou 515031, China
| |
Collapse
|
39
|
Moormann C, Artuc M, Pohl E, Varga G, Buddenkotte J, Vergnolle N, Brehler R, Henz BM, Schneider SW, Luger TA, Steinhoff M. Functional Characterization and Expression Analysis of the Proteinase-Activated Receptor-2 in Human Cutaneous Mast Cells. J Invest Dermatol 2006; 126:746-55. [PMID: 16470180 DOI: 10.1038/sj.jid.5700169] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Proteinase-activated receptor-2 (PAR2) belongs to a new G protein-coupled receptor subfamily activated by serine proteinases. PAR2 has been demonstrated to play a role during inflammation and immune response in different tissues including the skin. We examined whether PAR2 is functionally expressed by cutaneous human primary skin mast cells (HPMC) and the human mast cell line 1 (HMC-1). Reverse transcription-polymerase chain reaction and FACS analysis show expression of PAR2 both at the RNA and protein level. HPMCs and HMC-1 also express PAR1, PAR3, and PAR4. Ca-mobilization studies demonstrate functional PAR2 expressed by human skin mast cells, as shown by natural and synthetic PAR2 agonists. PAR2 agonists induced histamine release from HPMC indicating a role of PAR2 in regulating inflammatory and immune responses by skin mast cells. Double-immunofluorescence staining reveals colocalization of PAR2 with tryptase in the majority of human skin mast cells. In conclusion, trypsin and tryptase as well as specific agonists for PAR2 were able to induce Ca2+ mobilization in HPMCs, and agonists of PAR2 induce the release of histamine from these cells. Thus, PAR2 may be an important regulator of skin mast cell function during cutaneous inflammation and hypersensitivity.
Collapse
Affiliation(s)
- Corinna Moormann
- Department of Dermatology, IZKF Münster and Ludwig Boltzmann Institute for Cell- and Immunbiology of the Skin, University of Münster, Münster, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Henry PJ. The protease-activated receptor2 (PAR2)-prostaglandin E2-prostanoid EP receptor axis: a potential bronchoprotective unit in the respiratory tract? Eur J Pharmacol 2006; 533:156-70. [PMID: 16483565 DOI: 10.1016/j.ejphar.2005.12.051] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2005] [Indexed: 01/12/2023]
Abstract
Protease-activated receptor2 (PAR2) is a subtype of G protein-coupled receptor that is widely expressed within the respiratory tract. Stimulation of PAR2 by proteases such as trypsin and tryptase, or by small peptidic activators induces a complex array of effects within the airways. One such PAR2-mediated effect by basal airway epithelial cells is the generation of prostaglandin E2. Prostaglandin E2 produces a raft of anti-inflammatory effects within the airways, principally through the activation of the prostanoid EP2 and EP3 receptor subtypes. This article reviews the PAR2-prostaglandin E2-prostanoid EP receptor axis and discusses approaches through which its activation may provide beneficial effects in respiratory disease.
Collapse
MESH Headings
- Animals
- Anti-Inflammatory Agents/pharmacology
- Anti-Inflammatory Agents/therapeutic use
- Dinoprostone/metabolism
- Disease Models, Animal
- Humans
- Ligands
- Pneumonia/metabolism
- Pneumonia/prevention & control
- Receptor, PAR-2/drug effects
- Receptor, PAR-2/metabolism
- Receptors, Prostaglandin E/drug effects
- Receptors, Prostaglandin E/metabolism
- Receptors, Prostaglandin E, EP1 Subtype
- Receptors, Prostaglandin E, EP2 Subtype
- Receptors, Prostaglandin E, EP3 Subtype
- Respiratory Mucosa/drug effects
- Respiratory Mucosa/metabolism
- Respiratory System/drug effects
- Respiratory System/metabolism
Collapse
Affiliation(s)
- Peter J Henry
- School of Medicine and Pharmacology, University of Western Australia, Stirling Highway, Nedlands, Western Australia, 6009, Australia.
| |
Collapse
|
41
|
Wang L, Luo J, Fu Y, He S. Induction of interleukin-8 secretion and activation of ERK1/2, p38 MAPK signaling pathways by thrombin in dermal fibroblasts. Int J Biochem Cell Biol 2006; 38:1571-83. [PMID: 16697690 DOI: 10.1016/j.biocel.2006.03.016] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2005] [Revised: 03/12/2006] [Accepted: 03/25/2006] [Indexed: 02/05/2023]
Abstract
It was reported that thrombin could induce IL-8 secretion from human dermal fibroblasts (HDFs) through activation of proteinase activated receptor (PAR)-1. However, little is known of intracellular signaling pathways involved in the event. In the present study, expression of PARs in primarily cultured HDFs was determined by flow cytometry analysis and reverse transcription polymerase chain reaction (RT-PCR), levels of IL-8 were determined by using ELISA and signaling pathways were examined by using Western blot. It was found that HDFs express PAR-1 and PAR-3, and thrombin induces approximately 7.4-fold increase in IL-8 secretion from HDFs. Hirudin and a PAR-1 blocking antibody completely abolish the action of thrombin. It was also found that PD98059, a mitogen-activated protein kinase (MAPK) pathway inhibitor and U0126, an inhibitor of extracellular signal-regulated kinase (ERK) blocks thrombin-induced phosphorylation of ERK1/2 and IL-8 secretion, indicating the involvement of MAPK/ERK signaling pathway in thrombin-induced IL-8 secretion. p38 MAPK pathway appears also being involved as SB203580, a selective inhibitor of p38 MAPK inhibit phosphorylation of p38 MAPK and thrombin-induced IL-8 secretion. Furthermore, Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway, but not phosphotidylinositol 3-kinase (PI3K)/Akt signaling pathway may also be activated by thrombin. In conclusion, thrombin potently induce IL-8 release via PAR-1 from HDFs. Thrombin elicited IL-8 release is predominantly conducted through MAPK/ERK and p38 MAPK signaling pathways. Discovery of the signaling pathways of thrombin in HDFs may help to understand the role of thrombin in inflammation and tissue remodeling.
Collapse
Affiliation(s)
- Li Wang
- Allergy and Inflammation Research Institute, The Key Immunopathology Laboratory of Guangdong Province, The Shantou University Medical College, Shantou 515031, China
| | | | | | | |
Collapse
|
42
|
Abstract
Mast cells play a key role in the induction of allergic disorders, such as asthma and rhinitis, through the release of mediators including histamine, arachidonate products, proteases and several cytokines, which are found in relatively high quantities in these cells. A significant number of therapeutic approaches for allergies have been designed based on antagonising specific mediators released from mast cells and on selectively inhibiting the activation of these cells. Classical mast cell stabilisers, such as sodium cromoglycate, continue to attract new developments based on improved formulation and delivery systems, while efforts to identify new pathway (e.g., tyrosine kinase Syk) inhibitors or mediator (e.g., prostaglandin D2, beta-tryptase) antagonists may bring new successes to this field.
Collapse
|