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Bosma AL, Ascott A, Iskandar R, Farquhar K, Matthewman J, Langendam MW, Mulick A, Abuabara K, Williams HC, Spuls PI, Langan SM, Middelkamp-Hup MA. Classifying atopic dermatitis: a systematic review of phenotypes and associated characteristics. J Eur Acad Dermatol Venereol 2022; 36:807-819. [PMID: 35170821 PMCID: PMC9307020 DOI: 10.1111/jdv.18008] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 12/10/2021] [Accepted: 01/18/2022] [Indexed: 11/28/2022]
Abstract
Atopic dermatitis is a heterogeneous disease, accompanied by a wide variation in disease presentation and the potential to identify many phenotypes that may be relevant for prognosis and treatment. We aimed to systematically review previously reported phenotypes of atopic dermatitis and any characteristics associated with them. Ovid EMBASE, Ovid MEDLINE and Web of Science were searched from inception till the 12th of February 2021 for studies attempting to classify atopic dermatitis. Primary outcomes are atopic dermatitis phenotypes and characteristics associated with them in subsequent analyses. A secondary outcome is the methodological approach used to derive them. In total, 8,511 records were found. By focusing only on certain clinical phenotypes, 186 studies were eligible for inclusion. The majority of studies were hospital-based (59%, 109/186) and cross-sectional (76%, 141/186). The number of included patients ranged from seven to 526,808. Data-driven approaches to identify phenotypes were only used in a minority of studies (7%, 13/186). Ninety-one studies (49%) investigated a phenotype based on disease severity. A phenotype based on disease trajectory, morphology and eczema herpeticum was investigated in 56 (30%), 22 (12%) and 11 (6%) studies, respectively. Thirty-six studies (19%) investigated morphological characteristics in other phenotypes. Investigated associated characteristics differed between studies. In conclusion, we present an overview of phenotype definitions used in literature for severity, trajectory, morphology and eczema herpeticum, including associated characteristics. There is a lack of uniform and consistent use of atopic dermatitis phenotypes across studies.
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Affiliation(s)
- A L Bosma
- Department of Dermatology, UMC, location Academic Medical Center, University of Amsterdam, Amsterdam Public Health, Infection and Immunity, Amsterdam, The Netherlands
| | - A Ascott
- Department of Dermatology, University Hospitals Sussex NHS Foundation Trust, Worthing, United Kingdom
| | - R Iskandar
- Faculty of Epidemiology and Population Health, School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - J Matthewman
- Department of Non-communicable disease epidemiology, School of Hygiene and Tropical Medicine, London, United Kingdom
| | - M W Langendam
- Department of Epidemiology and Data Science, UMC, location Amsterdam Medical Center, University of Amsterdam, Amsterdam Public Health research institute, Amsterdam, The Netherlands
| | - A Mulick
- Faculty of Epidemiology and Population Health, School of Hygiene and Tropical Medicine, London, United Kingdom
| | - K Abuabara
- Department of Dermatology, University of California San Francisco, United States
| | - H C Williams
- Centre of Evidence-Based Dermatology, University of Nottingham, United Kingdom
| | - P I Spuls
- Department of Dermatology, UMC, location Academic Medical Center, University of Amsterdam, Amsterdam Public Health, Infection and Immunity, Amsterdam, The Netherlands
| | - S M Langan
- Department of Dermatology, UMC, location Academic Medical Center, University of Amsterdam, Amsterdam Public Health, Infection and Immunity, Amsterdam, The Netherlands.,Faculty of Epidemiology and Population Health, School of Hygiene and Tropical Medicine, London, United Kingdom
| | - M A Middelkamp-Hup
- Department of Dermatology, UMC, location Academic Medical Center, University of Amsterdam, Amsterdam Public Health, Infection and Immunity, Amsterdam, The Netherlands
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Sokolowska M, Rovati GE, Diamant Z, Untersmayr E, Schwarze J, Lukasik Z, Sava F, Angelina A, Palomares O, Akdis CA, O’Mahony L, Sanak M, Dahlen S, Woszczek G. Current perspective on eicosanoids in asthma and allergic diseases: EAACI Task Force consensus report, part I. Allergy 2021; 76:114-130. [PMID: 32279330 DOI: 10.1111/all.14295] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 03/13/2020] [Accepted: 03/25/2020] [Indexed: 12/25/2022]
Abstract
Eicosanoids are biologically active lipid mediators, comprising prostaglandins, leukotrienes, thromboxanes, and lipoxins, involved in several pathophysiological processes relevant to asthma, allergies, and allied diseases. Prostaglandins and leukotrienes are the most studied eicosanoids and established inducers of airway pathophysiology including bronchoconstriction and airway inflammation. Drugs inhibiting the synthesis of lipid mediators or their effects, such as leukotriene synthesis inhibitors, leukotriene receptors antagonists, and more recently prostaglandin D2 receptor antagonists, have been shown to modulate features of asthma and allergic diseases. This review, produced by an European Academy of Allergy and Clinical Immunology (EAACI) task force, highlights our current understanding of eicosanoid biology and its role in mediating human pathology, with a focus on new findings relevant for clinical practice, development of novel therapeutics, and future research opportunities.
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Affiliation(s)
- Milena Sokolowska
- Swiss Institute of Allergy and Asthma Research University of Zurich Davos Switzerland
- Christine Kühne ‐ Center for Allergy Research and Education (CK‐CARE) Davos Switzerland
| | - G. Enrico Rovati
- Department of Pharmaceutical Sciences University of Milan Milan Italy
| | - Zuzana Diamant
- Department of Respiratory Medicine & Allergology Skane University Hospital Lund Sweden
- Department of Respiratory Medicine First Faculty of Medicine Charles University and Thomayer Hospital Prague Czech Republic
| | - Eva Untersmayr
- Institute of Pathophysiology and Allergy Research Center for Pathophysiology, Infectiology and Immunology Medical University of Vienna Vienna Austria
| | - Jargen Schwarze
- Child Life and Health and Centre for Inflammation Research The University of Edinburgh Edinburgh UK
| | - Zuzanna Lukasik
- Swiss Institute of Allergy and Asthma Research University of Zurich Davos Switzerland
| | - Florentina Sava
- London North Genomic Laboratory Hub Great Ormond Street Hospital for Children NHS Foundation Trust London UK
| | - Alba Angelina
- Department of Biochemistry and Molecular Biology School of Chemistry Complutense University Madrid Spain
| | - Oscar Palomares
- Department of Biochemistry and Molecular Biology School of Chemistry Complutense University Madrid Spain
| | - Cezmi A. Akdis
- Swiss Institute of Allergy and Asthma Research University of Zurich Davos Switzerland
- Christine Kühne ‐ Center for Allergy Research and Education (CK‐CARE) Davos Switzerland
| | - Liam O’Mahony
- Departments of Medicine and Microbiology APC Microbiome Ireland University College Cork Cork Ireland
| | - Marek Sanak
- Department of Medicine Jagiellonian University Medical College Krakow Poland
| | - Sven‐Erik Dahlen
- Institute of Environmental Medicine Karolinska Institute Stockholm Sweden
- Centre for Allergy Research Karolinska Institute Stockholm Sweden
| | - Grzegorz Woszczek
- MRC/Asthma UK Centre in Allergic Mechanisms of Asthma School of Immunology & Microbial Sciences King's College London London UK
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Tsybikov NN, Petrisheva IV, Fefelova EV, Kuznik BI, Magen E. Plasma α-defensins are elevated during exacerbation of atopic dermatitis. Clin Exp Dermatol 2015; 41:253-9. [PMID: 26411782 DOI: 10.1111/ced.12767] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2015] [Indexed: 01/18/2023]
Abstract
BACKGROUND There is no currently no information regarding the role of α-defensins in the pathophysiology of atopic dermatitis (AD). AIM To investigate levels of plasma α-defensins at exacerbation and remission of AD, and to assess their association with clinical severity of AD. METHODS Patients with AD during exacerbation were recruited from the Dermatology department at the Chita Medical Academy (Chita, Russian Federation). SCORAD (SCORing Atopic Dermatitis), itch intensity, plasma concentrations of α-defensins, and serum total IgE, interleukin (IL)-1β, IL-8 and IL-10 levels were measured at study entry and after 4 months. RESULTS In total, 82 patients with AD [35 (45.1%) female and 47 (54.9%) male patients, mean ± SD age 42.2 ± 11.5 years, range 15-40] and 30 healthy controls (HCs) were included. Mean objective SCORAD score was 48.8 ± 19.4 and 16.1 ± 8.3 during AD during exacerbation and remission, respectively (P < 0.01). Plasma α-defensin levels in patients with AD (1.41 ± 0.32 μg/L) were significantly higher than in HCs (0.91 ± 0.34 μg/L) (P < 0.001). Significant correlations were found between plasma α-defensin levels with objective SCORAD (r = 0.55, P < 0.001), itch severity (r = 0.25, P < 0.05) and serum IgE levels (r = 0.38, P < 0.001) during AD exacerbation. Serum concentrations of IL-1β, IL-4 and IL-8 were significantly higher and levels of IL-10 were lower at AD exacerbation in patients than in HCs, with a weak negative correlation between plasma α-defensin and serum IL-10 levels (r = -0.22; P < 0.05). CONCLUSION During AD exacerbation, plasma α-defensin levels are elevated, and are positively correlated with AD clinical severity, itch intensity and serum IgE levels.
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Affiliation(s)
- N N Tsybikov
- Pathophysiology Department, Chita Medical Academy, Chita, Russia
| | - I V Petrisheva
- Pathophysiology Department, Chita Medical Academy, Chita, Russia
| | - E V Fefelova
- Pathophysiology Department, Chita Medical Academy, Chita, Russia
| | - B I Kuznik
- Normal Physiology Department, Chita Medical Academy, Chita, Russia
| | - E Magen
- Clinical Immunology and Allergy Unit, Medicine B Department, Barzilai Medical Center, Ben Gurion University of the Negev, Ashkelon, Israel
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Liu M, Yokomizo T. The role of leukotrienes in allergic diseases. Allergol Int 2015; 64:17-26. [PMID: 25572555 DOI: 10.1016/j.alit.2014.09.001] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 09/17/2014] [Accepted: 09/19/2014] [Indexed: 11/18/2022] Open
Abstract
Leukotrienes (LTs), both LTB4 and the cysteinyl LTs (CysLTs) LTC4, LTD4 and LTE4, are implicated in a wide variety of inflammatory disorders. These lipid mediators are generated from arachidonic acid via multistep enzymatic reactions through which arachidonic acid is liberated from membrane phospholipids through the action of phospholipase A2. LTB4 and CysLTs exert their biological effects by binding to cognate receptors, which belong to the G protein-coupled receptor superfamily. LTB4 is widely considered to be a potent chemoattractant for most subsets of leukocytes, whereas CysLTs are potent bronchoconstrictors that have effects on airway remodeling. LTs play a central role in the pathogenesis of asthma and many other inflammatory diseases. This review will provide an update on the synthesis, biological function, and relevance of LTs to the pathobiology of allergic diseases, and examine the current and future therapeutic prospects of LT modifiers.
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Affiliation(s)
- Min Liu
- Department of Biochemistry, Juntendo University School of Medicine, Tokyo, Japan; Department of Respiratory Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Takehiko Yokomizo
- Department of Biochemistry, Juntendo University School of Medicine, Tokyo, Japan.
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Mihály J, Gericke J, Törőcsik D, Gáspár K, Szegedi A, Rühl R. Reduced lipoxygenase and cyclooxygenase mediated signaling in PBMC of atopic dermatitis patients. Prostaglandins Other Lipid Mediat 2013; 107:35-42. [DOI: 10.1016/j.prostaglandins.2013.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Revised: 03/04/2013] [Accepted: 03/06/2013] [Indexed: 10/26/2022]
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Leukotriene B4-driven neutrophil recruitment to the skin is essential for allergic skin inflammation. Immunity 2012; 37:747-58. [PMID: 23063331 DOI: 10.1016/j.immuni.2012.06.018] [Citation(s) in RCA: 141] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 06/13/2012] [Accepted: 06/27/2012] [Indexed: 02/03/2023]
Abstract
Scratching triggers skin flares in atopic dermatitis. We demonstrate that scratching of human skin and tape stripping of mouse skin cause neutrophil influx. In mice, this influx was largely dependent on the generation of leukotriene B4 (LTB4) by neutrophils and their expression of the LTB4 receptor BLT1. Allergic skin inflammation in response to epicutaneous (EC) application of ovalbumin to tape-stripped skin was severely impaired in Ltb4r1(-/-) mice and required expression of BLT1 on both T cells and non-T cells. Cotransfer of wild-type (WT) neutrophils, but not neutrophils deficient in BLT1 or the LTB4-synthesizing enzyme LTA4H, restored the ability of WT CD4(+) effector T cells to transfer allergic skin inflammation to Ltb4r1(-/-) recipients. Pharmacologic blockade of LTB4 synthesis inhibited allergic skin inflammation elicited by cutaneous antigen challenge in previously EC-sensitized mice. Our results demonstrate that a neutrophil-T cell axis reliant on LTB4-BLT1 interaction is required for allergic skin inflammation.
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7
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Sandanayaka V, Mamat B, Mishra RK, Winger J, Krohn M, Zhou LM, Keyvan M, Enache L, Sullins D, Onua E, Zhang J, Halldorsdottir G, Sigthorsdottir H, Thorlaksdottir A, Sigthorsson G, Thorsteinnsdottir M, Davies DR, Stewart LJ, Zembower DE, Andresson T, Kiselyov AS, Singh J, Gurney ME. Discovery of 4-[(2S)-2-{[4-(4-chlorophenoxy)phenoxy]methyl}-1-pyrrolidinyl]butanoic acid (DG-051) as a novel leukotriene A4 hydrolase inhibitor of leukotriene B4 biosynthesis. J Med Chem 2010; 53:573-85. [PMID: 19950900 DOI: 10.1021/jm900838g] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Both in-house human genetic and literature data have converged on the identification of leukotriene 4 hydrolase (LTA(4)H) as a key target for the treatment of cardiovascular disease. We combined fragment-based crystallography screening with an iterative medicinal chemistry effort to optimize inhibitors of LTA(4)H. Ligand efficiency was followed throughout our structure-activity studies. As applied within the context of LTA(4)H inhibitor design, the chemistry team was able to design a potent compound 20 (DG-051) (K(d) = 26 nM) with high aqueous solubility (>30 mg/mL) and high oral bioavailability (>80% across species) that is currently undergoing clinical evaluation for the treatment of myocardial infarction and stroke. The structural biology-chemistry interaction described in this paper provides a sound alternative to conventional screening techniques. This is the first example of a gene-to-clinic paradigm enabled by a fragment-based drug discovery effort.
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Affiliation(s)
- Vincent Sandanayaka
- Medicinal Chemistry, deCODE Chemistry, Inc., 2501 Davey Road, Woodridge, Illinois 60517, USA
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8
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Ohnishi H, Miyahara N, Gelfand EW. The role of leukotriene B(4) in allergic diseases. Allergol Int 2008; 57:291-8. [PMID: 18797182 DOI: 10.2332/allergolint.08-rai-0019] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Indexed: 01/08/2023] Open
Abstract
Leukotriene B(4) (LTB(4)) is a lipid mediator with potent chemoattractant properties and that is rapidly generated from activated innate immune cells such as neutrophils, macrophages, and mast cells. Elevated levels of LTB(4) have been reported in various allergic diseases and these levels have been related to disease activity and response to treatment. Recent studies using LTB(4) receptor-1 (BLT1) antagonists or BLT1-deficient mice have revealed that ligation of BLT1 by LTB(4) is important for the activation and recruitment of inflammatory cells including neutrophils, eosinophils, monocytes/macrophages, mast cells, dendritic cells, and more recently, effector T cells to inflamed tissues in various inflammatory diseases. The LTB(4)/BLT1 pathway appears to play an important role in the pathogenesis of severe persistent asthma, aspirin- and exercise-induced asthma, allergic rhinitis, and atopic dermatitis together with other mediators including cysteinyl leukotrienes, cytokines, and chemokines. LTB(4) production is in general resistant to corticosteroid treatment. In fact, corticosteroids can upregulate BLT1 expression on corticosteroid-resistant inflammatory cells such as neutrophils, monocytes, and effector memory CD8+ T cells. As a result, this corticosteroid-resistant LTB(4)/BLT1 pathway may contribute to the development of inflammation in allergic diseases that do not respond to the introduction of corticosteroids. Inhibition of this pathway has potential therapeutic benefit in various allergic diseases that have involvement of corticosteroid-insensitivity.
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Affiliation(s)
- Hiroshi Ohnishi
- Department of Pediatrics, National Jewish Health, Denver, USA
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9
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Marsella R, Olivry T. The ACVD task force on canine atopic dermatitis (VII): mediators of cutaneous inflammation. Vet Immunol Immunopathol 2001; 81:205-13. [PMID: 11553381 DOI: 10.1016/s0165-2427(01)00300-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Controversy still exists on the role of various inflammatory mediators in the pathogenesis of canine atopic dermatitis. The objective of this article is to review the most recent information available on the inflammatory mediators that have been implicated in the pathogenesis of this disease. Studies on the role of histamine, serotonin, leukotrienes and various cytokines are presented in a comparative manner reviewing the experimental evidence for a role in the pathogenesis and the arguments against it.
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Affiliation(s)
- R Marsella
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, P.O. Box 100126, Gainesville, FL 32610-0126, USA.
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Marsella R, Nicklin CF. Sulphido-leukotriene production from peripheral leukocytes and skin in clinically normal dogs and house dust mite positive atopic dogs. Vet Dermatol 2001; 12:3-12. [PMID: 11301537 DOI: 10.1046/j.1365-3164.2001.00203.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pathogenesis of canine atopy has not been completely elucidated. In humans, sulphido-leukotrienes (s-LT) play a role in atopy, and increased production of s-LT occurs in the skin and peripheral leukocytes after allergen challenge. The study population included 16 clinically normal and 13 atopic dogs. All atopic dogs had in common a positive reaction (4+) to the intradermal injection of house dust mite (allergen of reference). Blood samples and skin biopsies were collected. Sulphido-LT synthesis by peripheral leukocytes after stimulation was measured, and no statistically significant difference was found between clinically normal and atopic dogs. Sulphido-LT concentrations in skin samples from stimulated and unstimulated sites were measured, and no statistically significant difference was detected between clinically normal and atopic dogs or between lesional and nonlesional skin within the atopic group. Clinical signs of atopic dogs were graded by owners and no correlation was found between their severity and cutaneous concentrations of s-LT. In this study there was no increase in s-LT synthesis in atopic dogs.
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Affiliation(s)
- R Marsella
- Blanche Saunders Dermatology Laboratory, Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, PO Box 100126, Gainesville, FL 32610-0126, USA
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11
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Affiliation(s)
- K Fogh
- Department of Dermatology, University of Aarhus, Marselisborg Hospital, Denmark
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12
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New induction of leukotriene A4 hydrolase by interleukin-4 and interleukin-13 in human polymorphonuclear leukocytes. Blood 2000. [DOI: 10.1182/blood.v96.2.601.014k21_601_609] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Interleukin (IL)-4, IL-10, and IL-13, Th2 cell–derived cytokines, play major roles in the pathophysiology of allergic diseases. These cytokines up-regulate or down-regulate the production of arachidonic acid metabolites. In this study, we have investigated the effect of IL-4, IL-10, IL-13, and other cytokines on A23187-stimulated synthesis of leukotriene (LT) B4 in human polymorphonuclear leukocytes (PMNs). Production of LTB4 was measured by specific radioimmunoassay and high performance liquid chromatography. Messenger RNA (mRNA) expression of cytosolic phospholipase A2 (cPLA2), 5-lipoxygenase (5-LO), and LTA4 hydrolase, which were involved in the synthesis of LTB4, was determined by reverse transcription–polymerase chain reaction and Northern blot analysis. Protein synthesis of their enzymes was determined by Western blot analysis. IL-4 and IL-13 enhanced A23187-stimulated LTB4 synthesis and increased mRNA expression and protein synthesis of LTA4hydrolase, but not those of cPLA2 or 5-LO. These results indicate that IL-4 and IL-13 transcriptionally or post-transcriptionally up-regulate the synthesis of LTB4, a potent chemotactic factor to PMNs, at the enzyme level of LTA4 hydrolase, and this up-regulation mechanism may participate in the development of allergic inflammation.
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13
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New induction of leukotriene A4 hydrolase by interleukin-4 and interleukin-13 in human polymorphonuclear leukocytes. Blood 2000. [DOI: 10.1182/blood.v96.2.601] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractInterleukin (IL)-4, IL-10, and IL-13, Th2 cell–derived cytokines, play major roles in the pathophysiology of allergic diseases. These cytokines up-regulate or down-regulate the production of arachidonic acid metabolites. In this study, we have investigated the effect of IL-4, IL-10, IL-13, and other cytokines on A23187-stimulated synthesis of leukotriene (LT) B4 in human polymorphonuclear leukocytes (PMNs). Production of LTB4 was measured by specific radioimmunoassay and high performance liquid chromatography. Messenger RNA (mRNA) expression of cytosolic phospholipase A2 (cPLA2), 5-lipoxygenase (5-LO), and LTA4 hydrolase, which were involved in the synthesis of LTB4, was determined by reverse transcription–polymerase chain reaction and Northern blot analysis. Protein synthesis of their enzymes was determined by Western blot analysis. IL-4 and IL-13 enhanced A23187-stimulated LTB4 synthesis and increased mRNA expression and protein synthesis of LTA4hydrolase, but not those of cPLA2 or 5-LO. These results indicate that IL-4 and IL-13 transcriptionally or post-transcriptionally up-regulate the synthesis of LTB4, a potent chemotactic factor to PMNs, at the enzyme level of LTA4 hydrolase, and this up-regulation mechanism may participate in the development of allergic inflammation.
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14
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Abstract
Arachidonic acid (5.8,11,14-eicosatetraenoic acid C20:4, n-6) is released from the cell membrane by the action of phospholipases on membrane phospholipids. Metabolites of arachidonic acid, which are generically termed eicosanoids, including prostaglandins, thromboxane, leukotrienes and hydroxyeicosatetraenoic acids, have been implicated as mediators or modulators of a number of physiological functions and pathological conditions in both normal and diseased human skin. Particularly, eicosanoids have been suspected to play an important role in the pathogenesis of psoriasis, because a number of phenomena observed in psoriasis can be explained, at least in part, by the action of eicosanoids. This review will focus on recent progress regarding the significance of eicosanoids in the pathogenesis of psoriasis. Recent developments in the molecular biology in the eicosanoids have renewed interest in the role of eicosanoids in psoriasis. New understanding of the etiology of psoriasis and advances in its treatment due to recent progress in eicosanoid biology will also be presented.
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Affiliation(s)
- K Ikai
- Department of Dermatology, Kyoto University, Graduate School of Medicine, Japan.
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