101
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Simpson EL, Williams H, Chalmers J. Reply. J Allergy Clin Immunol 2015; 135:1664. [DOI: 10.1016/j.jaci.2015.01.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 01/30/2015] [Indexed: 11/25/2022]
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102
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Sakai T, Hatano Y, Matsuda-Hirose H, Nishiyori R, Fujiwara S. Atopic dermatitis-like dermatitis emerges unevenly on different sites in flaky tail mice. J Dermatol Sci 2015; 78:151-3. [DOI: 10.1016/j.jdermsci.2015.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/05/2015] [Accepted: 01/19/2015] [Indexed: 12/20/2022]
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103
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Brandner JM, Zorn-Kruppa M, Yoshida T, Moll I, Beck LA, De Benedetto A. Epidermal tight junctions in health and disease. Tissue Barriers 2015; 3:e974451. [PMID: 25838981 DOI: 10.4161/21688370.2014.974451] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 10/04/2014] [Indexed: 01/21/2023] Open
Abstract
The skin, the largest organ of the body, is an essential barrier that under homeostatic conditions efficiently protects and/or minimizes damage from both environmental (e.g. microorganisms, physical trauma, ultraviolet radiation) and endogenous (e.g., cancers, inflammation) factors. This formidable barrier function resides mainly in the epidermis, a dynamic, highly-stratified epithelium. The epidermis has 2 major barrier structures: stratum corneum, the outmost layer and tight junctions, intercellular junctions that seal adjacent keratinocytes in the stratum granulosum, found below the stratum corneum. In recent years there have been significant advances in our understanding of tight junction function, composition and regulation. Herein we review what is known about tight junctions in healthy skin and keratinocyte culture systems and highlight the dynamic crosstalk observed between tight junctions and the cutaneous immune system. Finally we discuss the preliminary observations suggesting that tight junction function or protein expression may be relevant for the pathogenesis of a number of common cutaneous inflammatory and neoplastic conditions.
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Key Words
- AD, atopic dermatitis
- AMP, antimicrobial peptides
- Cldn, claudin
- DC, dendritic cells
- FLG, filaggrin
- JAM, junctional adhesion molecule
- LC, Langerhans cells
- MM, malignant melanoma
- PRR, pattern recognition receptor
- PS, psoriasis
- SCC, squamous cell carcinoma; SC, stratum corneum
- SG, stratum granulosum
- SNP, single nucleotide polymorphism
- TER, TransEpithelial Electrical Resistance
- TJ, tight junction
- TLR, Toll-like receptor
- Th, T helper
- ZO-1, zonula occludens 1
- claudins
- skin barrier
- skin immune system
- skin innate barrier
- tight junction
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Affiliation(s)
- J M Brandner
- Department of Dermatology and Venereology; University Hospital Hamburg-Eppendorf ; Hamburg, Germany
| | - M Zorn-Kruppa
- Department of Dermatology and Venereology; University Hospital Hamburg-Eppendorf ; Hamburg, Germany
| | - T Yoshida
- Department of Dermatology; University of Rochester Medical Center ; Rochester, NY USA
| | - I Moll
- Department of Dermatology and Venereology; University Hospital Hamburg-Eppendorf ; Hamburg, Germany
| | - L A Beck
- Department of Dermatology; University of Rochester Medical Center ; Rochester, NY USA
| | - A De Benedetto
- Department of Dermatology; University of Rochester Medical Center ; Rochester, NY USA
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104
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Mast cells are dispensable in a genetic mouse model of chronic dermatitis. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:1575-87. [PMID: 25843682 DOI: 10.1016/j.ajpath.2015.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 01/26/2015] [Accepted: 02/12/2015] [Indexed: 01/12/2023]
Abstract
Chronic inflammatory skin diseases, such as atopic dermatitis, affect a large percentage of the population, but the role of different immune cells in the pathogenesis of these disorders is largely unknown. Recently, we found that mice lacking fibroblast growth factor receptor 1 (Fgfr1) and Fgfr2 (K5-R1/R2 mice) in the epidermis have a severe impairment in the epidermal barrier, which leads to the development of a chronic inflammatory skin disease that shares many features with human atopic dermatitis. Using Fgfr1-/Fgfr2-deficient mice, we analyzed the consequences of the loss of mast cells. Mast cells accumulated and degranulated in the skin of young Fgfr1-/Fgfr2-deficient mice, most likely as a consequence of increased expression of the mast cell chemokine Ccl2. The increase in mast cells occurred before the development of histological abnormalities, indicating a functional role of these cells in the inflammatory skin phenotype. To test this hypothesis, we mated the Fgfr1-/Fgfr2-deficient mice with mast cell-deficient CreMaster mice. Surprisingly, loss of mast cells did not or only mildly affect keratinocyte proliferation, epidermal thickness, epidermal barrier function, accumulation and activation of different immune cells, or expression of different proinflammatory cytokines in the skin. These results reveal that mast cells are dispensable for the development of chronic inflammation in response to a defect in the epidermal barrier.
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105
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Matsui T, Amagai M. Dissecting the formation, structure and barrier function of the stratum corneum. Int Immunol 2015; 27:269-80. [PMID: 25813515 DOI: 10.1093/intimm/dxv013] [Citation(s) in RCA: 213] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 03/19/2015] [Indexed: 02/06/2023] Open
Abstract
The skin is the largest organ of the mammalian body. The outermost layer of mammalian skin, the stratum corneum (SC) of the epidermis, consists of piles of dead corneocytes that are the end-products of terminal differentiation of epidermal keratinocytes. The SC performs a crucial barrier function of epidermis. Langerhans cells, when activated, extend their dendrites through tight junctions just beneath the SC to capture external antigens. Recently, knowledge of the biology of corneocytes ('corneobiology') has progressed rapidly and many key factors that modulate its barrier function have been identified and characterized. In this review article on the SC, we summarize its evolution, formation, structure and function. Cornification is an important step of SC formation at the conversion of living epithelial cells to dead corneocytes, and consists of three major steps: formation of the intracellular keratin network, cornified envelopes and intercellular lipids. After cornification, the SC undergoes chemical reactions to form the mature SC with different functional layers. Finally, the SC is shed off at the surface ('desquamation'), mediated by a cascade of several proteases. This review will be helpful to understand our expanding knowledge of the biology of the SC, where immunity meets external antigens.
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Affiliation(s)
- Takeshi Matsui
- Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences (IMS), 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Masayuki Amagai
- Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences (IMS), 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan Department of Dermatology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
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106
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van Drongelen V, Danso MO, Out JJ, Mulder A, Lavrijsen APM, Bouwstra JA, El Ghalbzouri A. Explant cultures of atopic dermatitis biopsies maintain their epidermal characteristics in vitro. Cell Tissue Res 2015; 361:789-97. [PMID: 25776938 DOI: 10.1007/s00441-015-2162-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 02/23/2015] [Indexed: 02/05/2023]
Abstract
Atopic dermatitis (AD) is a common inflammatory skin disorder characterised by various epidermal alterations. Filaggrin (FLG) mutations are a major predisposing factor for AD and much research has been focused on the FLG protein. Human skin equivalents (HSEs) might be useful tools for increasing our understanding of FLG in AD and to provide a tool for the screening of new therapies aimed at FLG replacement. Our aim is to establish an explant HSE (Ex-HSE) for AD by using non-lesional skin from AD patients wildtype for FLG or harbouring homozygous FLG mutations. These Ex-HSEs were evaluated as to whether they maintained their in vivo characteristics in vitro and whether FLG mutations affected the expression of various differentiation markers. FLG mutations did not affect the outgrowth from the biopsy for the establishment of Ex-HSEs. FLG expression was present in healthy skin and that of AD patients without FLG mutations and in their Ex-HSEs but was barely present in biopsies from patients with FLG mutations and their corresponding Ex-HSEs. AD Ex-HSEs and AD biopsies shared many similarities, i.e., proliferation and the expression of keratin 10 and loricrin, irrespective of FLG mutations. Neither KLK5 nor Lekti expression was affected by FLG mutations but was altered in the respective Ex-HSEs. Thus, Ex-HSEs established from biopsies taken from AD patients maintain their FLG genotype-phenotype in vitro and the expression of most proteins in vivo and in vitro remains similar. Our method is therefore promising as an alternative to genetic engineering approaches in the study of the role of FLG in AD.
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Affiliation(s)
- Vincent van Drongelen
- Gorlaeus Laboratories, Department of Drug Delivery Technology, Leiden Academy Centre for Drug Research, Leiden University, Leiden, The Netherlands,
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107
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Gillespie RMC, Brown SJ. From the outside-in: Epidermal targeting as a paradigm for atopic disease therapy. World J Dermatol 2015; 4:16-32. [DOI: 10.5314/wjd.v4.i1.16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Revised: 11/29/2014] [Accepted: 12/17/2014] [Indexed: 02/06/2023] Open
Abstract
Atopic dermatitis (AD) is a chronic inflammatory skin disorder which can precede asthma and allergic rhinitis in a disease trajectory known as the atopic march. The pathophysiology of AD includes cutaneous inflammation, disrupted epidermal barrier function, xerosis and propensity to secondary infections. AD had previously been thought to arise from the systemic atopic immune response and therapies are therefore directed towards ameliorating Th2-mediated inflammation. However in recent years the focus has shifted towards primary defects in the skin barrier as an initiating event in AD. Links between loss-of-function variants in the gene encoding filaggrin and disrupted activity of epidermal serine proteases and AD have been reported. Based on these observations, a mechanism has been described by which epidermal barrier dysfunction may lead to inflammation and allergic sensitization. Exogenous and endogenous stressors can further exacerbate inherited barrier abnormalities to promote disease activity. Pathways underlying progression of the atopic march remain unclear, but recent findings implicate thymic stromal lymphopoietin as a factor linking AD to subsequent airway inflammation in asthma. This new appreciation of the epidermis in the development of AD should lead to deployment of more specific strategies to restore barrier function in atopic patients and potentially halt the atopic march.
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108
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Hoff S, Oyoshi MK, Macpherson A, Geha RS. The microbiota is important for IL-17A expression and neutrophil infiltration in lesional skin of Flg(ft/ft) mice. Clin Immunol 2014; 156:128-30. [PMID: 25499749 DOI: 10.1016/j.clim.2014.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Accepted: 12/08/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Sabine Hoff
- Division of Immunology, Boston Children's Hospital, Boston, MA, USA
| | - Michiko K Oyoshi
- Division of Immunology, Boston Children's Hospital, Boston, MA, USA
| | - Andrew Macpherson
- Division of Gastroenterology and Mucosal Immunology, University of Bern, Bern, Switzerland
| | - Raif S Geha
- Division of Immunology, Boston Children's Hospital, Boston, MA, USA.
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109
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Abstract
Atopic dermatitis (AD) or eczema is a chronic inflammatory skin disorder with significant morbidity and quality of life impairment. Elucidating the epidemiology of AD is important for understanding disease risk factors and facilitates development of interventions for disease prevention. This contribution aims to summarize recent developments in the epidemiology of AD, including the US prevalence, regional differences, and secular trends of disease prevalence, genetic and environmental determinants, distribution, and determinants of disease severity and health care use for AD.
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110
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Leung DYM, Guttman-Yassky E. Deciphering the complexities of atopic dermatitis: shifting paradigms in treatment approaches. J Allergy Clin Immunol 2014; 134:769-79. [PMID: 25282559 PMCID: PMC4186710 DOI: 10.1016/j.jaci.2014.08.008] [Citation(s) in RCA: 311] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 08/12/2014] [Accepted: 08/12/2014] [Indexed: 12/14/2022]
Abstract
Atopic dermatitis (AD) is the most common chronic inflammatory skin disease. It often precedes the development of food allergy and asthma. Recent insights into AD reveal abnormalities in terminal differentiation of the epidermal epithelium leading to a defective stratum corneum, which allows enhanced allergen penetration and systemic IgE sensitization. Atopic skin is also predisposed to colonization or infection by pathogenic microbes, most notably Staphylococcus aureus and herpes simplex virus. Causes of this abnormal skin barrier are complex and driven by a combination of genetic, environmental, and immunologic factors. These factors likely account for the heterogeneity of AD onset and the severity and natural history of this skin disease. Recent studies suggest prevention of AD can be achieved through early interventions to protect the skin barrier. Onset of lesional AD requires effective control of local and systemic immune activation for optimal management. Early intervention might improve long-term outcomes for AD and reduce the systemic allergen sensitization that leads to associated allergic diseases in the gastrointestinal and respiratory tract.
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Affiliation(s)
- Donald Y M Leung
- Division of Pediatric Allergy-Immunology, Department of Pediatrics, National Jewish Health, Denver, Colo.
| | - Emma Guttman-Yassky
- Department of Dermatology and the Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
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111
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Elias PM, Wakefield JS. Mechanisms of abnormal lamellar body secretion and the dysfunctional skin barrier in patients with atopic dermatitis. J Allergy Clin Immunol 2014; 134:781-791.e1. [PMID: 25131691 DOI: 10.1016/j.jaci.2014.05.048] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 04/29/2014] [Accepted: 05/07/2014] [Indexed: 12/22/2022]
Abstract
I review how diverse inherited and acquired abnormalities in epidermal structural and enzymatic proteins converge to produce defective permeability barrier function and antimicrobial defense in patients with atopic dermatitis (AD). Although best known are mutations in filaggrin (FLG), mutations in other member of the fused S-100 family of proteins (ie, hornerin [hrn] and filaggrin 2 [flg-2]); the cornified envelope precursor (ie, SPRR3); mattrin, which is encoded by TMEM79 and regulates the assembly of lamellar bodies; SPINK5, which encodes the serine protease inhibitor lymphoepithelial Kazal-type trypsin inhibitor type 1; and the fatty acid transporter fatty acid transport protein 4 have all been linked to AD. Yet these abnormalities often only predispose to AD; additional acquired stressors that further compromise barrier function, such as psychological stress, low ambient humidity, or high-pH surfactants, often are required to trigger disease. T(H)2 cytokines can also compromise barrier function by downregulating expression of multiple epidermal structural proteins, lipid synthetic enzymes, and antimicrobial peptides. All of these inherited and acquired abnormalities converge on the lamellar body secretory system, producing abnormalities in lipid composition, secretion, and/or extracellular lamellar membrane organization, as well as antimicrobial defense. Finally, I briefly review therapeutic options that address this new pathogenic paradigm.
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Affiliation(s)
- Peter M Elias
- Dermatology Service, Veterans Affairs Medical Center, and the Department of Dermatology, University of California, San Francisco, Calif.
| | - Joan S Wakefield
- Dermatology Service, Veterans Affairs Medical Center, and the Department of Dermatology, University of California, San Francisco, Calif
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112
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Lessons learned from mice and man: mimicking human allergy through mouse models. Clin Immunol 2014; 155:1-16. [PMID: 25131136 DOI: 10.1016/j.clim.2014.08.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 08/06/2014] [Accepted: 08/07/2014] [Indexed: 01/06/2023]
Abstract
The relevance of using mouse models to represent human allergic pathologies is still unclear. Recent studies suggest the limitations of using models as a standard for assessing immune response and tolerance mechanisms, as mouse models often do not sufficiently depict human atopic conditions. Allergy is a combination of aberrant responses to innocuous environmental agents and the subsequent TH2-mediated inflammatory responses. In this review, we will discuss current paradigms of allergy - specifically, TH2-mediated and IgE-associated immune responses - and current mouse models used to recreate these TH2-mediated pathologies. Our overall goal is to highlight discrepancies that exist between mice and men by examining the advantages and disadvantages of allergic mouse models with respect to the human allergic condition.
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113
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Nakajima S, Kitoh A, Egawa G, Natsuaki Y, Nakamizo S, Moniaga CS, Otsuka A, Honda T, Hanakawa S, Amano W, Iwakura Y, Nakae S, Kubo M, Miyachi Y, Kabashima K. IL-17A as an Inducer for Th2 Immune Responses in Murine Atopic Dermatitis Models. J Invest Dermatol 2014; 134:2122-2130. [DOI: 10.1038/jid.2014.51] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 12/03/2013] [Accepted: 12/24/2013] [Indexed: 12/12/2022]
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114
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Clinical Management of Atopic Dermatitis: Practical Highlights and Updates from the Atopic Dermatitis Practice Parameter 2012. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY-IN PRACTICE 2014; 2:361-9; quiz 370. [DOI: 10.1016/j.jaip.2014.02.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 02/25/2014] [Accepted: 02/26/2014] [Indexed: 11/20/2022]
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115
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Cipolat S, Hoste E, Natsuga K, Quist SR, Watt FM. Epidermal barrier defects link atopic dermatitis with altered skin cancer susceptibility. eLife 2014; 3:e01888. [PMID: 24843010 PMCID: PMC4007207 DOI: 10.7554/elife.01888] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Atopic dermatitis can result from loss of structural proteins in the outermost epidermal layers, leading to a defective epidermal barrier. To test whether this influences tumour formation, we chemically induced tumours in EPI−/− mice, which lack three barrier proteins—Envoplakin, Periplakin, and Involucrin. EPI−/− mice were highly resistant to developing benign tumours when treated with 7,12-dimethylbenz(a)anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA). The DMBA response was normal, but EPI−/− skin exhibited an exaggerated atopic response to TPA, characterised by abnormal epidermal differentiation, a complex immune infiltrate and elevated serum thymic stromal lymphopoietin (TSLP). The exacerbated TPA response could be normalised by blocking TSLP or the immunoreceptor NKG2D but not CD4+ T cells. We conclude that atopy is protective against skin cancer in our experimental model and that the mechanism involves keratinocytes communicating with cells of the immune system via signalling elements that normally protect against environmental assaults. DOI:http://dx.doi.org/10.7554/eLife.01888.001 Skin cancer is a common and growing problem—according to the World Health Organization, skin cancers account for one in every three cancers diagnosed world wide. There is some evidence from epidemiological studies that patients with certain allergies might be protected against cancer and, in particular, that the allergic skin condition atopic dermatitis is associated with reduced levels of various skin cancers. However, it is difficult to know if this reduction is due to the atopic dermatitis itself or to the drugs used to treat this allergy. Genetically engineered mice that are lacking three proteins that are involved in the formation of the cornified envelope—the protective layer that replaces the normal plasma membrane in the cells of the outermost skin layers—can be used to study atopic dermatitis. These ‘triple knockout mice’ have a defective epidermal barrier and altered levels of immune T-cells in the skin. Now Cipolat et al. have investigated whether defects in the epidermal barrier protect against skin cancer. Knockout mice and wild-type mice were treated with two chemicals: DMBA, which causes mutations in a gene called HRas, and TPA, which promotes the formation of tumours from cells that contain HRas mutations. After about 16 weeks almost all of the wild-type mice had at least one benign tumour, whereas half of the knockout mice had no tumours. Overall, the average number of benign tumours per mouse was six times higher in the wild-type mice. This shows that the mutations that cause the epidermal barrier defects in knockout mice also protect them against the tumours caused by the combined effects of DMBA and TPA. Cipolat et al. then compared how the mice responded to DMBA or TPA alone. The knockout mice and the wild-type mice responded to DMBA in the same way; however, the knockout mice showed an exaggerated response to TPA, including a strong inflammatory reaction. This response comprised the production of higher levels of various proteins that are involved in communications between skin cells and the immune system. Cipolat et al. propose that the immune reaction caused by this exaggerated response could help to prevent tumour formation by eliminating tumour-forming cells in the skin. DOI:http://dx.doi.org/10.7554/eLife.01888.002
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Affiliation(s)
- Sara Cipolat
- Centre for Stem Cells and Regenerative Medicine, King's College London, London, United Kingdom Cancer Research UK Cambridge Research Institute, Cambridge, United Kingdom
| | - Esther Hoste
- Centre for Stem Cells and Regenerative Medicine, King's College London, London, United Kingdom Cancer Research UK Cambridge Research Institute, Cambridge, United Kingdom
| | - Ken Natsuga
- Cancer Research UK Cambridge Research Institute, Cambridge, United Kingdom Department of Dermatology, Hokkaido University, Sapporo, Japan
| | - Sven R Quist
- Cancer Research UK Cambridge Research Institute, Cambridge, United Kingdom Department of Dermatology and Venereology, Otto von Guericke University Magdeburg, Magdeburg, Germany
| | - Fiona M Watt
- Centre for Stem Cells and Regenerative Medicine, King's College London, London, United Kingdom
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116
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Abstract
The epidermis functions as a physical barrier to the external environment and works to prevent loss of water from the skin. Numerous factors have been implicated in the formation of epidermal barriers, such as cornified envelopes, corneocytes, lipids, junctional proteins, proteases, protease inhibitors, antimicrobial peptides, and transcription factors. This review illustrates human diseases (ichthyoses) and animal models in which the epidermal barrier is disrupted or dysfunctional at steady state owing to ablation of one or more of the above factors. These diseases and animal models help us to understand the complicated mechanisms of epidermal barrier formation and give further insights on epidermal development.
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117
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Lee HJ, Lee SH. Epidermal permeability barrier defects and barrier repair therapy in atopic dermatitis. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2014; 6:276-87. [PMID: 24991450 PMCID: PMC4077953 DOI: 10.4168/aair.2014.6.4.276] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Accepted: 01/06/2014] [Indexed: 12/18/2022]
Abstract
Atopic dermatitis (AD) is a multifactorial inflammatory skin disease perpetuated by gene-environmental interactions and which is characterized by genetic barrier defects and allergic inflammation. Recent studies demonstrate an important role for the epidermal permeability barrier in AD that is closely related to chronic immune activation in the skin during systemic allergic reactions. Moreover, acquired stressors (e.g., Staphylococcus aureus infection) to the skin barrier may also initiate inflammation in AD. Many studies involving patients with AD revealed that defective skin barriers combined with abnormal immune responses might contribute to the pathophysiology of AD, supporting the outside-inside hypothesis. In this review, we discuss the recent advances in human and animal models, focusing on the defects of the epidermal permeability barrier, its immunologic role and barrier repair therapy in AD.
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Affiliation(s)
- Hae-Jin Lee
- Medical Corps of Sangmudae Army Service Support Group, Republic of Korea Army Training and Doctrine Command, Jangsung, Korea
| | - Seung-Hun Lee
- Department of Dermatology, Gangnam Severance Hospital, Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea
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118
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Sprecher E, Leung DYM. Atopic dermatitis: scratching through the complexity of barrier dysfunction. J Allergy Clin Immunol 2014; 132:1130-1. [PMID: 24176684 DOI: 10.1016/j.jaci.2013.09.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 09/19/2013] [Indexed: 12/18/2022]
Affiliation(s)
- Eli Sprecher
- Department of Dermatology, Tel Aviv Sourasky Medical Center, Tela Aviv, Israel; Department of Human Molecular Genetics & Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel
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119
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Sicherer SH, Leung DYM. Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2013. J Allergy Clin Immunol 2013; 133:324-34. [PMID: 24373349 DOI: 10.1016/j.jaci.2013.11.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 11/19/2013] [Indexed: 02/07/2023]
Abstract
This review highlights some of the research advances in anaphylaxis; hypersensitivity reactions to foods, drugs, and insects; and allergic skin diseases that were reported in the Journal in 2013. Studies on food allergy suggest that (1) 7.6% of the US population is affected, (2) a "healthy" early diet might prevent food allergy, (3) the skin might be an important route of sensitization, (4) allergen component testing might aid diagnosis, (5) the prognosis of milk allergy might be predictable through early testing, (6) oral or sublingual immunotherapy show promise but also have caveats, and (7) preclinical studies show promising alternative modes of immunotherapy and desensitization. Studies on eosinophilic esophagitis show a relationship to connective tissue disorders and that dietary management is an effective treatment for adults. Markers of anaphylaxis severity have been determined and might inform potential diagnostics and therapeutic targets. Insights on serum tests for drug and insect sting allergy might result in improved diagnostics. Genetic and immune-mediated defects in skin epithelial differentiation contribute to the severity of atopic dermatitis. Novel management approaches to treatment of chronic urticaria, including use of omalizumab, are being identified.
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Affiliation(s)
- Scott H Sicherer
- Elliot and Roslyn Jaffe Food Allergy Institute, Division of Allergy and Immunology, Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY.
| | - Donald Y M Leung
- Department of Pediatrics, Division of Pediatric Allergy/Immunology, National Jewish Health, Denver, Colo
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