1
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Pan Y, Hochgerner M, Cichoń MA, Benezeder T, Bieber T, Wolf P. Langerhans cells: Central players in the pathophysiology of atopic dermatitis. J Eur Acad Dermatol Venereol 2024. [PMID: 39157943 DOI: 10.1111/jdv.20291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Accepted: 07/21/2024] [Indexed: 08/20/2024]
Abstract
Atopic dermatitis (AD) is the most common chronic inflammatory skin disease worldwide. AD is a highly complex disease with different subtypes. Many elements of AD pathophysiology have been described, but if/how they interact with each other or which mechanisms are important in which patients is still unclear. Langerhans cells (LCs) are antigen-presenting cells (APCs) in the epidermis. Depending on the context, they can act either pro- or anti-inflammatory. Many different studies have investigated LCs in the context of AD and found them to be connected to all major mechanisms of AD pathophysiology. As APCs, LCs recruit other immune cells and shape the immune response, especially adaptive immunity via polarization of T cells. As sentinel cells, LCs are primary sensors of the skin microbiome and are important for the decision of immunity versus tolerance. LCs are also involved with the integrity of the skin barrier by influencing tight junctions. Finally, LCs are important cells in the neuro-immune crosstalk in the skin. In this review, we provide an overview about the many different roles of LCs in AD. Understanding LCs might bring us closer to a more complete understanding of this highly complex disease. Potentially, modulating LCs might offer new options for targeted therapies for AD patients.
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Affiliation(s)
- Yi Pan
- Department of Dermatology and Allergy, University Hospital of Bonn, Bonn, Germany
- Department of Dermatology and Venerology, Medical University of Graz, Graz, Austria
| | - Mathias Hochgerner
- Greater Bay Area Institute of Precision Medicine (Guangzhou), School of Life Sciences, Fudan University, Shanghai, China
| | | | - Theresa Benezeder
- Department of Dermatology and Venerology, Medical University of Graz, Graz, Austria
| | - Thomas Bieber
- Department of Dermatology and Allergy, University Hospital of Bonn, Bonn, Germany
- CK-CARE, Medicine Campus, Davos, Switzerland
- Department of Dermatology, University Hospital of Zürich, Zürich, Switzerland
| | - Peter Wolf
- Department of Dermatology and Venerology, Medical University of Graz, Graz, Austria
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2
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Yamamoto-Hanada K, Ohya Y. Management of Infant Atopic Eczema to Prevent Severe Eczema and Food Allergy. Clin Exp Allergy 2024. [PMID: 38866599 DOI: 10.1111/cea.14515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/20/2024] [Accepted: 05/23/2024] [Indexed: 06/14/2024]
Abstract
Early intervention and active management of infant atopic eczema may play a crucial role in limiting eczema severity and preventing the onset of immediate-type food allergy. Eczema management involves education, skincare and medications targeting skin inflammation and barrier repair. Topical corticosteroids are the mainstay of anti-inflammatory therapy, with nonsteroidal options available for some infants. Proactive therapy, addressing subclinical inflammation, is useful for preventing eczema flares, especially in infants with recurrent eczema flares despite reactive therapy. In clinical practice, holistic consideration of overall infant and family health is essential. Providing advice on maternal stress management, nutritional guidance and recommendations for proper sleep and lifestyle is crucial for the well-being of children and their families, not limited to eczema treatment alone.
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Affiliation(s)
| | - Yukihiro Ohya
- Allergy Center, National Center for Child Health and Development, Tokyo, Japan
- Department of Occupational and Environmental Health, Nagoya City University Graduate School of Medical Sciences, Aichi, Japan
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3
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Schuler CF, Tsoi LC, Billi AC, Harms PW, Weidinger S, Gudjonsson JE. Genetic and Immunological Pathogenesis of Atopic Dermatitis. J Invest Dermatol 2024; 144:954-968. [PMID: 38085213 PMCID: PMC11040454 DOI: 10.1016/j.jid.2023.10.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/05/2023] [Accepted: 10/25/2023] [Indexed: 02/03/2024]
Abstract
Type 2 immune-mediated diseases give a clear answer to the issue of nature (genetics) versus nurture (environment). Both genetics and environment play vital complementary roles in the development of atopic dermatitis (AD). As a key component of the atopic march, AD demonstrates the interactive nature of genetic and environmental contributions to atopy. From sequence variants in the epithelial barrier gene encoding FLG to the hygiene hypothesis, AD combines a broad array of contributions into a single syndrome. This review will focus on the genetic contribution to AD and where genetics facilitates the elicitation or enhancement of AD pathogenesis.
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Affiliation(s)
- Charles F Schuler
- Division of Allergy and Clinical Immunology, Department of Internal Medicine, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA; Mary H. Weiser Food Allergy Center, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Lam C Tsoi
- Mary H. Weiser Food Allergy Center, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA; Department of Dermatology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Allison C Billi
- Department of Dermatology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Paul W Harms
- Department of Dermatology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA; Department of Pathology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Stephan Weidinger
- Department of Dermatology, Venereology, and Allergology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Johann E Gudjonsson
- Mary H. Weiser Food Allergy Center, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA; Department of Dermatology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA.
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4
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Lapp T, Mann C, Jakob T, Reinhard T, Maier PC. Atopic Keratoconjunctivitis: Pathophysiology, Clinic, and Potential New Therapeutic Concepts. Klin Monbl Augenheilkd 2024; 241:607-618. [PMID: 38604222 DOI: 10.1055/a-2244-2885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
Atopic dermatitis (AD) is a chronic recurrent inflammatory skin disease with a bipolar age distribution in childhood, adolescence and middle adulthood. Up to 50% of AD patients show ocular involvement, which can be potentially sight threatening. Clinically, the majority of cases present with atopic blepharo(kerato)conjunctivitis or atopic keratoconjunctivitis (AKC); other clinical variants from this group of inflammatory ocular surface diseases are keratoconjunctivitis vernalis in childhood and adolescence and allergic conjunctivitis. In addition to the aforementioned blepharitis, keratitis and conjunctivitis, AD is also associated with eyelid involvement with subsequent eyelid malposition, limbal insufficiency with the development of pseudopterygia, (chronic) cicatrizing conjunctivitis with symblephara formation and fornix shortening, as well as ocular surface malignancies such as conjunctival intraepithelial neoplasia (CIN) and squamous cell carcinoma. In addition, an association with AD or AKC has been described for keratoconus. Whereas the therapy of AD in dermatology has made revolutionary advances in recent years through the use of biologicals, the primary use of these biologicals in ophthalmological complications is still very hesitant. Treatment here is often provided using topical steroids and calcineurin inhibitors. The following article summarises recent developments in basic and clinical dermatological research and discusses them in the context of current concepts for ophthalmological therapy.
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Affiliation(s)
- Thabo Lapp
- Klinik für Augenheilkunde, Universitätsklinikum Freiburg, Deutschland
- Augenzentrum am St. Franziskus Hospital, Münster, Deutschland
| | - Caroline Mann
- Haut- und Poliklinik, Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Deutschland
| | - Thilo Jakob
- Klinik für Dermatologie und Allergologie, Universitätsklinikum Gießen und Marburg, Gießen, Deutschland
| | - Thomas Reinhard
- Klinik für Augenheilkunde, Universitätsklinikum Freiburg, Deutschland
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5
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Guo Z, Murakami M, Saito K, Kato H, Toriyama M, Tominaga M, Ishii KJ, Fujita F. Integrin α5 regulates motility of human monocyte-derived Langerhans cells during immune response. Exp Dermatol 2024; 33:e15021. [PMID: 38429832 DOI: 10.1111/exd.15021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/28/2023] [Accepted: 01/12/2024] [Indexed: 03/03/2024]
Abstract
Langerhans cells (LCs) are mainly present in the epidermis and mucosa, and have important roles during skin infection. Migration of LCs to lymph nodes is essential for antigen presentation. However, due to the difficulties in isolating and culturing human LCs, it is not fully understood how LCs move and interact with the extracellular matrix (ECM) through their adhesion molecules such as integrin, during the immune responses. In this study, we aimed to investigate LC motility, cell shape and the role of integrin under inflammatory conditions using monocyte-derived Langerhans cells (moLCs) as a model. As a result, lipopolysaccharide (LPS) stimulation increased adhesion on fibronectin coated substrate and integrin α5 expression in moLCs. Time-lapse imaging of moLCs revealed that stimulation with LPS elongated cell shape, whilst decreasing their motility. Additionally, this decrease in motility was not observed when pre-treated with a neutralising antibody targeting integrin α5. Together, our data suggested that activation of LCs decreases their motility by promoting integrin α5 expression to enhance their affinity to the fibronectin, which may contribute to their migration during inflammation.
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Affiliation(s)
- Zhihan Guo
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
| | - Masato Murakami
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
- Skin Care Institute, Mandom Corporation, Osaka, Japan
| | - Kaori Saito
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
- Advanced Technology Institute, Mandom Corporation, Osaka, Japan
- Center for Vaccine and Adjuvant Research, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
| | - Hiroko Kato
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
- Center for Vaccine and Adjuvant Research, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
| | - Manami Toriyama
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
- Center for Vaccine and Adjuvant Research, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Nara, Japan
| | - Makoto Tominaga
- Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, Okazaki, Japan
- National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Japan
- Department of Physiological Sciences, Sokendai (The Graduate University for Advanced Studies), Okazaki, Japan
| | - Ken J Ishii
- Center for Vaccine and Adjuvant Research, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
- Division of Vaccine Science, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Fumitaka Fujita
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
- Advanced Technology Institute, Mandom Corporation, Osaka, Japan
- Center for Vaccine and Adjuvant Research, National Institutes of Biomedical Innovation, Health and Nutrition, Osaka, Japan
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Wang X, Mao D, Jia J, Zhang J. Benvitimod Inhibits IL-4- and IL-13-Induced Tight Junction Impairment by Activating AHR/ARNT Pathway and Inhibiting STAT6 Phosphorylation in Human Keratinocytes. J Invest Dermatol 2024; 144:509-519.e7. [PMID: 37734479 DOI: 10.1016/j.jid.2023.07.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 07/05/2023] [Accepted: 07/22/2023] [Indexed: 09/23/2023]
Abstract
Tight junctions are involved in skin barrier functions. In this study, the expression of CLDN1, CLDN4, and OCLN was found to decrease in skin lesions of atopic dermatitis by bioinformatics analysis. Immunohistochemistry staining in skin specimens from 12 patients with atopic dermatitis and 12 healthy controls also showed decreased CLDN1, CLDN4, and OCLN expression in atopic dermatitis lesions. In vitro studies showed that IL-4 and IL-13 downregulated CLDN1, CLDN4, and OCLN expression in HaCaT cells as well as CLDN4 and OCLN expression in human primary keratinocytes. This effect, which was mediated through the Jak-signal transducer and activator of transcription 6 signaling pathway, increased paracellular flux of 4-kDa dextran. Benvitimod, a new drug for atopic dermatitis, upregulated CLDN4 and OCLN through the aryl hydrocarbon receptor/aryl hydrocarbon receptor nuclear translocator pathway. Benvitimod induced nuclear translocation of NRF2 and reduced production of ROS in keratinocytes, thus inhibiting IL-4-/IL-13-induced CLDN1 downregulation and signal transducer and activator of transcription 6 phosphorylation. These results indicate that T helper 2 cytokines are involved in tight junction impairment, and benvitimod can inhibit these effects.
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Affiliation(s)
- Xiaojie Wang
- Department of Dermatology, Peking University People's Hospital, Beijing, China
| | - Dandan Mao
- Department of Dermatology, Peking University People's Hospital, Beijing, China
| | - Jun Jia
- Department of Dermatology, Peking University People's Hospital, Beijing, China
| | - Jianzhong Zhang
- Department of Dermatology, Peking University People's Hospital, Beijing, China.
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7
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Del Duca E, He H, Liu Y, Pagan AD, David E, Cheng J, Carroll B, Renert-Yuval Y, Bar J, Estrada YD, Maari C, Proulx ESC, Krueger JG, Bissonnette R, Guttman-Yassky E. Intrapatient comparison of atopic dermatitis skin transcriptome shows differences between tape-strips and biopsies. Allergy 2024; 79:80-92. [PMID: 37577841 DOI: 10.1111/all.15845] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/26/2023] [Accepted: 06/24/2023] [Indexed: 08/15/2023]
Abstract
BACKGROUND Our knowledge of etiopathogenesis of atopic dermatitis (AD) is largely derived from skin biopsies, which are associated with pain, scarring and infection. In contrast, tape-stripping is a minimally invasive, nonscarring technique to collect skin samples. METHODS To construct a global AD skin transcriptomic profile comparing tape-strips to whole-skin biopsies, we performed RNA-seq on tape-strips and biopsies taken from the lesional skin of 20 moderate-to-severe AD patients and the skin of 20 controls. Differentially expressed genes (DEGs) were defined by fold-change (FCH) ≥2.0 and false discovery rate <0.05. RESULTS We detected 4104 (2513 Up; 1591 Down) and 1273 (546 Up; 727 Down) DEGs in AD versus controls, in tape-strips and biopsies, respectively. Although both techniques captured dysregulation of key immune genes, tape-strips showed higher FCHs for innate immunity (IL-1B, IL-8), dendritic cell (ITGAX/CD11C, FCER1A), Th2 (IL-13, CCL17, TNFRSF4/OX40), and Th17 (CCL20, CXCL1) products, while biopsies showed higher upregulation of Th22 associated genes (IL-22, S100As) and dermal cytokines (IFN-γ, CCL26). Itch-related genes (IL-31, TRPV3) were preferentially captured by tape-strips. Epidermal barrier abnormalities were detected in both techniques, with terminal differentiation defects (FLG2, PSORS1C2) better represented by tape-strips and epidermal hyperplasia changes (KRT16, MKI67) better detected by biopsies. CONCLUSIONS Tape-strips and biopsies capture overlapping but distinct features of the AD molecular signature, suggesting their respective utility for monitoring specific AD-related immune, itch, and barrier abnormalities in clinical trials and longitudinal studies.
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Affiliation(s)
- Ester Del Duca
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Dermatology, University of Magna Graecia, Catanzaro, Italy
| | - Helen He
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Ying Liu
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Angel D Pagan
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Eden David
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Julia Cheng
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Britta Carroll
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Yael Renert-Yuval
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Laboratory for Investigative Dermatology, The Rockefeller University, New York City, New York, USA
| | - Jonathan Bar
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Yeriel D Estrada
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | | | | | - James G Krueger
- Laboratory for Investigative Dermatology, The Rockefeller University, New York City, New York, USA
| | | | - Emma Guttman-Yassky
- Department of Dermatology, and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
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8
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Dessì A, Di Maria C, Pintus R, Fanos V, Bosco A. Lipidomics and Metabolomics in Infant Atopic Dermatitis: What's the Correlation with Early Nutrition? Curr Pediatr Rev 2024; 20:510-524. [PMID: 37055903 DOI: 10.2174/1573396320666230411093122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 02/22/2023] [Accepted: 03/02/2023] [Indexed: 04/15/2023]
Abstract
To date, the complex picture of atopic dermatitis (AD) has not yet been fully clarified, despite the important prevalence of this disease in the pediatric population (20%) and the possibility of persistence into adulthood, with important implications for the quality of life of those affected, as well as significant social and financial costs. The most recent scientific evidence suggests a new interpretation of AD, highlighting the important role of the environment, particularly that of nutrition in the early stages of development. In fact, the new indications seem to point out the harmful effect of elimination diets, except in rare cases, the uselessness of chrono-insertions during complementary feeding and some benefits, albeit weak, of breastfeeding in those at greater risk. In this context, metabolomics and lipidomics can be necessary for a more in-depth knowledge of the complex metabolic network underlying this pathology. In fact, an alteration of the metabolic contents in children with AD has been highlighted, especially in correlation to the intestinal microbiota. While preliminary lipidomic studies showed the usefulness of a more in-depth knowledge of the alterations of the skin barrier to improve the development of baby skin care products. Therefore, investigating the response of different allergic phenotypes could be useful for better patient management and understanding, thus providing an early intervention on dysbiosis necessary to regulate the immune response from the earliest stages of development.
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Affiliation(s)
- Angelica Dessì
- Department of Surgical Sciences, University of Cagliari and Neonatal Intensive Care Unit, AOU Cagliari, Cagliari, Italy
| | - Camilla Di Maria
- Department of Surgical Sciences, University of Cagliari and Neonatal Intensive Care Unit, AOU Cagliari, Cagliari, Italy
| | - Roberta Pintus
- Department of Surgical Sciences, University of Cagliari and Neonatal Intensive Care Unit, AOU Cagliari, Cagliari, Italy
| | - Vassilios Fanos
- Department of Surgical Sciences, University of Cagliari and Neonatal Intensive Care Unit, AOU Cagliari, Cagliari, Italy
| | - Alice Bosco
- Department of Surgical Sciences, University of Cagliari and Neonatal Intensive Care Unit, AOU Cagliari, Cagliari, Italy
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9
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Zhou J, Liang G, Liu L, Feng S, Zheng Z, Wu Y, Chen X, Li X, Wang L, Wang L, Song Z. Single-cell RNA-seq reveals abnormal differentiation of keratinocytes and increased inflammatory differentiated keratinocytes in atopic dermatitis. J Eur Acad Dermatol Venereol 2023; 37:2336-2348. [PMID: 37326015 DOI: 10.1111/jdv.19256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 04/26/2023] [Indexed: 06/17/2023]
Abstract
BACKGROUND Atopic dermatitis (AD) is a chronic and recurrent inflammatory skin disease characterized by severe pruritus and eczematous lesions. Heterogeneity of AD has been reported among different racial groups according to clinical, molecular and genetic differences. OBJECTIVE This study aimed to conduct an in-depth transcriptome analysis of AD in Chinese population. METHODS We performed single-cell RNA sequencing (scRNA-seq) analysis of skin biopsies from five Chinese adult patients with chronic AD and from four healthy controls, combined with multiplexed immunohistochemical analysis in whole-tissue skin biopsies. We explored the functions of IL19 in vitro. RESULTS ScRNA-seq analysis was able to profile a total of 87,853 cells, with keratinocytes (KCs) in AD manifesting highly expressed keratinocyte activation and pro-inflammatory genes. KCs demonstrated a novel IL19+ IGFL1+ subpopulation that increased in AD lesions. Inflammatory cytokines IFNG, IL13, IL26 and IL22 were highly expressed in AD lesions. In vitro, IL19 directly downregulated KRT10 and LOR in HaCaT cells and activated HaCaT cells to produce TSLP. CONCLUSION Abnormal proliferation and differentiation of keratinocytes contribute immensely to the pathogenesis of AD, whereas AD chronic lesions have witnessed significant presence of IL19+ IGFL1+ KCs, which may be involved in the disruption of the skin barrier, the connection and magnification of Th2 and Th17 inflammatory responses, and mediation of skin pruritus. Furthermore, progressive activation of multiple immune axes dominated by Type 2 inflammatory reaction occur in AD chronic lesions.
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Affiliation(s)
- Jie Zhou
- Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Gaopeng Liang
- Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Lu Liu
- Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Shujing Feng
- Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Zhengni Zheng
- Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Yaguang Wu
- Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, China
| | - Xiaoling Chen
- Institute of Immunology PLA & Department of Immunology, Army Medical University, Chongqing, China
| | - Xiangqian Li
- Institute of Immunology PLA & Department of Immunology, Army Medical University, Chongqing, China
| | - Lina Wang
- Institute of Immunology PLA & Department of Immunology, Army Medical University, Chongqing, China
- Department of Immunology, College of Basic Medicine, Qingdao University, Qingdao, China
- Department of Immunology, College of Basic Medicine, Weifang Medical University, Weifang, China
| | - Li Wang
- Institute of Immunology PLA & Department of Immunology, Army Medical University, Chongqing, China
| | - Zhiqiang Song
- Department of Dermatology, Southwest Hospital, Army Medical University, Chongqing, China
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10
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Moran MC, Brewer MG, Schlievert PM, Beck LA. S. aureus virulence factors decrease epithelial barrier function and increase susceptibility to viral infection. Microbiol Spectr 2023; 11:e0168423. [PMID: 37737609 PMCID: PMC10581065 DOI: 10.1128/spectrum.01684-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 07/03/2023] [Indexed: 09/23/2023] Open
Abstract
Individuals with atopic dermatitis (AD) are highly colonized by Staphylococcus aureus and are more susceptible to severe viral complications. We hypothesized that S. aureus secreted virulence factors may alter keratinocyte biology to enhance viral susceptibility through disruption of the skin barrier, impaired keratinocyte differentiation, and/or inflammation. To address this hypothesis, human keratinocytes were exposed to conditioned media from multiple S. aureus strains that vary in virulence factor production (USA300, HG003, and RN4220) or select purified virulence factors. We have identified the S. aureus enterotoxin-like superantigen SElQ, as a virulence factor of interest, since it is highly produced by USA300 and was detected on the skin of 53% of AD subjects (n = 72) in a study conducted by our group. Treatment with USA300 conditioned media or purified SElQ resulted in a significant increase in keratinocyte susceptibility to infection with vaccinia virus, and also significantly decreased barrier function. Importantly, we have previously demonstrated that keratinocyte differentiation influences susceptibility to viral infection, and our qPCR observations indicated that USA300 S. aureus and SElQ alter differentiation in keratinocytes. CRISPR/Cas9 was used to knock out CD40, a potential enterotoxin receptor on epithelial cells. We found that CD40 expression on keratinocytes was not completely necessary for SElQ-mediated responses, as measured by proinflammatory cytokine expression and barrier function. Together, these findings support that select S. aureus virulence factors, particularly SElQ, enhance the susceptibility of epidermal cells to viral infection, which may contribute to the increased cutaneous infections observed in individuals with AD. IMPORTANCE Staphylococcus aureus skin colonization and infection are frequently observed in individuals with atopic dermatitis. Many S. aureus strains belong to the clonal group USA300, and these strains produce superantigens including the staphylococcal enterotoxin-like Q (SElQ). Our studies highlight that SElQ may play a key role by altering keratinocyte differentiation and reducing barrier function; collectively, this may explain the AD-specific enhanced infection risk to cutaneous viruses. It is unclear what receptor mediates SElQ's effects on keratinocytes. We have shown that one putative surface receptor, CD40, was not critical for its effects on proinflammatory cytokine production or barrier function.
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Affiliation(s)
- Mary C. Moran
- Department of Dermatology, University of Rochester Medical Center, Rochester, New York, USA
- Department of Microbiology & Immunology, University of Rochester Medical Center, Rochester, New York, USA
| | - Matthew G. Brewer
- Department of Dermatology, University of Rochester Medical Center, Rochester, New York, USA
| | | | - Lisa A. Beck
- Department of Dermatology, University of Rochester Medical Center, Rochester, New York, USA
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11
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Yamaguchi HL, Yamaguchi Y, Peeva E. Role of Innate Immunity in Allergic Contact Dermatitis: An Update. Int J Mol Sci 2023; 24:12975. [PMID: 37629154 PMCID: PMC10455292 DOI: 10.3390/ijms241612975] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/15/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023] Open
Abstract
Our understanding of allergic contact dermatitis mechanisms has progressed over the past decade. Innate immune cells that are involved in the pathogenesis of allergic contact dermatitis include Langerhans cells, dermal dendritic cells, macrophages, mast cells, innate lymphoid cells (ILCs), neutrophils, eosinophils, and basophils. ILCs can be subcategorized as group 1 (natural killer cells; ILC1) in association with Th1, group 2 (ILC2) in association with Th2, and group 3 (lymphoid tissue-inducer cells; ILC3) in association with Th17. Pattern recognition receptors (PRRs) including toll-like receptors (TLRs) and nucleotide-binding oligomerization domain (NOD)-like receptors (NLRs) in innate immune cells recognize damage-associated molecular patterns (DAMPs) and cascade the signal to produce several cytokines and chemokines including tumor necrosis factor (TNF)-α, interferon (IFN)-α, IFN-γ, interleukin (IL)-1β, IL-4, IL-6, IL-12, IL-13, IL-17, IL-18, and IL-23. Here we discuss the recent findings showing the roles of the innate immune system in allergic contact dermatitis during the sensitization and elicitation phases.
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Affiliation(s)
| | - Yuji Yamaguchi
- Inflammation & Immunology Research Unit, Pfizer, Collegeville, PA 19426, USA
| | - Elena Peeva
- Inflammation & Immunology Research Unit, Pfizer, Cambridge, MA 02139, USA
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12
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Katsarou S, Makris M, Vakirlis E, Gregoriou S. The Role of Tight Junctions in Atopic Dermatitis: A Systematic Review. J Clin Med 2023; 12:jcm12041538. [PMID: 36836073 PMCID: PMC9967084 DOI: 10.3390/jcm12041538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/31/2023] [Accepted: 02/10/2023] [Indexed: 02/17/2023] Open
Abstract
BACKGROUND Tight junctions are transmembrane proteins that regulate the permeability of water, solutes including ions, and water-soluble molecules. The objective of this systematic review is to focus on the current knowledge regarding the role of tight junctions in atopic dermatitis and the possible impact on their therapeutic potential. METHODS A literature search was performed in PubMed, Google Scholar, and Cochrane library between 2009 and 2022. After evaluation of the literature and taking into consideration their content, 55 articles were finally included. RESULTS TJs' role in atopic dermatitis extends from a microscopic scale to having macroscopic effects, such as increased susceptibility to pathogens and infections and worsening of atopic dermatitis features. Impaired TJ barrier function and skin permeability in AD lesions is correlated with cldn-1 levels. Th2 inflammation inhibits the expression of cldn-1 and cldn-23. Scratching has also been reported to decrease cldn-1 expression. Dysfunctional TJs' interaction with Langerhans cells could increase allergen penetration. Susceptibility to cutaneous infections in AD patients could also be affected by TJ cohesion. CONCLUSIONS Dysfunction of TJs and their components, especially claudins, have a significant role in the pathogenesis and vicious circle of inflammation in AD. Discovering more basic science data regarding TJ functionality may be the key for the use of specific/targeted therapies in order to improve epidermal barrier function in AD.
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Affiliation(s)
- Spyridoula Katsarou
- 1st Department of Dermatology and Venereology, Medical School, National and Kapodistrian University of Athens, Andreas Syggros Hospital, 11528 Athens, Greece
- Correspondence:
| | - Michael Makris
- 2nd Department of Dermatology and Venereology, Medical School, National and Kapodistrian University of Athens, Attikon University Hospital, Allergy Unit, 12461 Athens, Greece
| | - Efstratios Vakirlis
- 1st Department of Dermatology and Venereology, Medical School, Aristotle University, 54124 Thessaloniki, Greece
| | - Stamatios Gregoriou
- 1st Department of Dermatology and Venereology, Medical School, National and Kapodistrian University of Athens, Andreas Syggros Hospital, 11528 Athens, Greece
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13
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Abe N, Iwata N, Yasuoka R, Nishida D, Oohara A, Nakaseko H, Sugiura S, Kawabe S. Risk factors for intolerance of oral 5-aminosalicylic acid preparations in pediatric ulcerative colitis. Pediatr Int 2023; 65:e15553. [PMID: 37551649 DOI: 10.1111/ped.15553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 04/18/2023] [Accepted: 04/27/2023] [Indexed: 08/09/2023]
Abstract
BACKGROUND No previous study of Japanese children with ulcerative colitis (UC) has reported the risk factors for intolerance of 5-aminosalicylic acid (5-ASA). We aimed to identify risk factors for intolerance of oral 5-ASA preparations in pediatric UC. METHODS Patients with childhood-onset UC who were seen at our hospital between November 2003 and March 2020 were investigated. Intolerance of 5-ASA was defined as having clinical symptoms (pyrexia, abdominal pain, diarrhea, bloody stool) that worsened after starting oral administration of 5-ASA and improved after discontinuation of 5-ASA. Patient sex, age, body size, laboratory data, pediatric UC activity index scores, and colonoscopy-based determinations of the extent and severity of the affected lesion at initiation of 5-ASA of intolerant and tolerant groups were compared. RESULTS Fifteen patients were in the intolerant group, and 37 were in the tolerant group. The leukocyte count, C-reactive protein level, and erythrocyte sedimentation rate were significantly higher in the intolerant group than the tolerant group; the albumin level in the intolerant group was significantly lower. All intolerant patients and 68% of tolerant patients had pancolitis (Paris classification E4). Patients with a large, affected area (Paris classifications E3 and E4) more frequently had intolerance to 5-ASA than patients with a small lesion. The cumulative Mayo endoscopic subscore (cMES), which is the sum of MES scores for six regions of the large intestine, was significantly higher in the intolerant group. CONCLUSIONS Pediatric UC patients with more intense inflammation and a large lesion could have an increased risk of intolerance for 5-ASA.
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Affiliation(s)
- Naoki Abe
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
| | - Naomi Iwata
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
| | - Ryuhei Yasuoka
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
- Department of Pediatrics, Hamamatsu University School of Medicine, Shizuoka, Japan
| | - Daisuke Nishida
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
| | - Asami Oohara
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
| | - Haruna Nakaseko
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
| | - Shiro Sugiura
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
| | - Shinji Kawabe
- Department of Allergy and Immunology, Aichi Children's Health and Medical Center, Obu, Japan
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14
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Involvement of Atopic Dermatitis in the Development of Systemic Inflammatory Diseases. Int J Mol Sci 2022; 23:ijms232113445. [PMID: 36362231 PMCID: PMC9658023 DOI: 10.3390/ijms232113445] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 10/29/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
The skin is recognized as a peripheral lymphoid organ that plays an essential defensive action against external environmental stimuli. However, continuous stimulation of these factors causes chronic inflammation at the local site and occasionally causes tissue damage. Chronic inflammation is recognized as a trigger for systemic organ inflammation. Atopic dermatitis (AD) is a chronic inflammatory skin disease that is influenced by various external environmental factors, such as dry conditions, chemical exposure, and microorganisms. The pathogenesis of AD involves various Th2 and proinflammatory cytokines. Recently updated studies have shown that atopic skin-derived cytokines influence systemic organ function and oncogenesis. In this review, we focus on AD’s influence on the development of systemic inflammatory diseases and malignancies.
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15
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The Acari Hypothesis, III: Atopic Dermatitis. Pathogens 2022; 11:pathogens11101083. [DOI: 10.3390/pathogens11101083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/12/2022] [Accepted: 09/20/2022] [Indexed: 11/17/2022] Open
Abstract
Atopic dermatitis is a chronic relapsing dermatopathology involving IgE against allergenic materials present on mammalian epithelial surfaces. Allergens are as diverse as pet danders, and polypeptides expressed by microbes of the mammalian microbiome, e.g., Malassezia spp. The Acari Hypothesis posits that the mammalian innate immune system utilizes pathogen-bound acarian immune effectors to protect against the vectorial threat posed by mites and ticks. Per The Hypothesis, IgE-mediated allergic disease is a specious consequence of the pairing of acarian gastrointestinal materials, e.g., allergenic foodstuffs, with acarian innate immune effectors that have interspecies operability. In keeping with The Hypothesis, the IgE profile of atopic patients should include both anti-acarian antibodies and specious antibodies responsible for specific allergy. Further, the profile should inform on the diet and/or environment of the acarian vector. In this regard, the prevalence of Demodex and Dermatophagoides on the skin of persons suffering from atopic dermatitis is increased. Importantly, the diets of these mites correspond well with the allergens of affected patients. In this report, roles for these specific acarians in the pathogenesis of atopic dermatitis are proposed and elaborated.
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16
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Herpes Simplex Virus 1 Can Bypass Impaired Epidermal Barriers upon Ex Vivo Infection of Skin from Atopic Dermatitis Patients. J Virol 2022; 96:e0086422. [PMID: 35969080 PMCID: PMC9472615 DOI: 10.1128/jvi.00864-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
To infect its human host, herpes simplex virus 1 (HSV-1) must overcome the protective barriers of skin and mucosa. Here, we addressed whether pathological skin conditions can facilitate viral entry via the skin surface and used ex vivo infection studies to explore viral invasion in atopic dermatitis (AD) skin characterized by disturbed barrier functions. Our focus was on the visualization of the onset of infection in single cells to determine the primary entry portals in the epidermis. After ex vivo infection of lesional AD skin, we observed infected cells in suprabasal layers indicating successful invasion in the epidermis via the skin surface which was never detected in control skin where only sample edges allowed viral access. The redistribution of filaggrin, loricrin, and tight-junction components in the lesional skin samples suggested multiple defective mechanical barriers. To dissect the parameters that contribute to HSV-1 invasion, we induced an AD-like phenotype by adding the Th2 cytokines interleukin 4 (IL-4) and IL-13 to healthy human skin samples. Strikingly, we detected infected cells in the epidermis, implying that the IL-4/IL-13-driven inflammation is sufficient to induce modifications allowing HSV-1 to penetrate the skin surface. In summary, not only did lesional AD skin facilitate HSV-1 penetration but IL-4/IL-13 responses alone allowed virus invasion. Our results suggest that the defective epidermal barriers of AD skin and the inflammation-induced altered barriers in healthy skin can make receptors accessible for HSV-1. IMPORTANCE Herpes simplex virus 1 (HSV-1) can target skin to establish primary infection in the epithelium. While the human skin provides effective barriers against viral invasion under healthy conditions, a prominent example of successful invasion is the disseminated HSV-1 infection in the skin of atopic dermatitis (AD) patients. AD is characterized by impaired epidermal barrier functions, chronic inflammation, and dysbiosis of skin microbiota. We addressed the initial invasion process of HSV-1 in atopic dermatitis skin to understand whether the physical barrier functions are sufficiently disturbed to allow the virus to invade skin and reach its receptors on skin cells. Our results demonstrate that HSV-1 can indeed penetrate and initiate infection in atopic dermatitis skin. Since treatment of skin with IL-4 and IL-13 already resulted in successful invasion, we assume that inflammation-induced barrier defects play an important role for the facilitated access of HSV-1 to its target cells.
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17
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Vasicine alleviates 2,4-dinitrochlorobenzene-induced atopic dermatitis and passive cutaneous anaphylaxis in BALB/c mice. Clin Immunol 2022; 244:109102. [DOI: 10.1016/j.clim.2022.109102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 08/12/2022] [Accepted: 08/24/2022] [Indexed: 11/19/2022]
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18
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Kubo A, Aoki S, Fujita H. Whole-Mount Preparation and Microscopic Analysis of Epidermis. Curr Protoc 2022; 2:e464. [PMID: 35816161 DOI: 10.1002/cpz1.464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The epidermis is a stratified epithelium. Compared to that for monolayered epithelia, understanding of the cell biology of stratified epithelia lags far behind. The major reason for this is the limitation of methods to reproduce the epidermis in vitro using cultured keratinocytes: for example, cultured keratinocyte cell sheets lack Langerhans cells, melanocytes, nerves, sweat ducts, and hair follicles. One current way to overcome this limitation is to observe the epidermis in vivo via whole-mount staining and three-dimensional imaging. Here, we describe how to prepare epidermal sheets from skin and how to immunostain and observe them in whole mount. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Preparation of mouse epidermal sheets by the ammonium thiocyanate method Alternate Protocol: Preparation of mouse epidermal sheets by the dispase method Basic Protocol 2: Preparation of human epidermal sheets by the dispase method Basic Protocol 3: Whole-mount immunostaining of epidermis.
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Affiliation(s)
- Akiharu Kubo
- Division of Dermatology, Department of Internal Related, Kobe University Graduate School of Medicine, Kobe, Japan
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan
| | - Satomi Aoki
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan
| | - Harumi Fujita
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan
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19
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Immunological Pathomechanisms of Spongiotic Dermatitis in Skin Lesions of Atopic Dermatitis. Int J Mol Sci 2022; 23:ijms23126682. [PMID: 35743125 PMCID: PMC9223609 DOI: 10.3390/ijms23126682] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 06/10/2022] [Accepted: 06/13/2022] [Indexed: 12/18/2022] Open
Abstract
Atopic dermatitis (AD) is a chronic pruritic skin disease with a complex pathogenesis underlying its heterogeneous clinical phenotypes and endotypes. The skin manifestation of AD reflects the cytokine milieu of a type-2-dominant immunity axis induced by genetic predisposition, innate immunity dysregulation, epidermal barrier defects, and allergic inflammation. However, the detailed pathomechanism of eczematous dermatitis, which is the principal characteristic of AD, remains unclear. This review examines previous studies demonstrating research progress in this area and considers the immunological pathomechanism of “spongiotic dermatitis”, which is the histopathological hallmark of eczematous dermatitis. Studies in this field have revealed the importance of IgE-mediated delayed-type hypersensitivity, the Fas/Fas-ligand system, and cell-mediated cytotoxicity in inducing the apoptosis of keratinocytes in spongiotic dermatitis. Recent studies have demonstrated that, together with infiltrating CD4 T cells, IgE-expressing dendritic cells (i.e., inflammatory dendritic epidermal cells and Langerhans cells) that capture specific allergens (i.e., house dust mites) are present in the spongiotic epidermis of lichenified eczema in patients with IgE-allergic AD. These findings suggest that IgE-mediated delayed-type hypersensitivity plays a pivotal role in the pathogenesis of spongiotic dermatitis in the skin lesions of AD.
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20
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Beck LA, Cork MJ, Amagai M, De Benedetto A, Kabashima K, Hamilton JD, Rossi AB. Type 2 Inflammation Contributes to Skin Barrier Dysfunction in Atopic Dermatitis. JID INNOVATIONS 2022; 2:100131. [PMID: 36059592 PMCID: PMC9428921 DOI: 10.1016/j.xjidi.2022.100131] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 01/04/2022] [Accepted: 01/06/2022] [Indexed: 01/02/2023] Open
Abstract
Skin barrier dysfunction, a defining feature of atopic dermatitis (AD), arises from multiple interacting systems. In AD, skin inflammation is caused by host-environment interactions involving keratinocytes as well as tissue-resident immune cells such as type 2 innate lymphoid cells, basophils, mast cells, and T helper type 2 cells, which produce type 2 cytokines, including IL-4, IL-5, IL-13, and IL-31. Type 2 inflammation broadly impacts the expression of genes relevant for barrier function, such as intracellular structural proteins, extracellular lipids, and junctional proteins, and enhances Staphylococcus aureus skin colonization. Systemic anti‒type 2 inflammation therapies may improve dysfunctional skin barrier in AD.
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Key Words
- AD, atopic dermatitis
- AMP, antimicrobial peptide
- CLDN, claudin
- FFA, free fatty acid
- ILC2, type 2 innate lymphoid cell
- Jaki, Jak inhibitor
- K, keratin
- KC, keratinocyte
- MMP, matrix metalloproteinase
- NMF, natural moisturizing factor
- PAR, protease-activated receptor
- PDE-4, phosphodiesterase-4
- SC, stratum corneum
- SG, stratum granulosum
- TCI, topical calcineurin inhibitor
- TCS, topical corticosteroid
- TEWL, transepidermal water loss
- TJ, tight junction
- TLR, toll-like receptor
- TNF-α, tumor necrosis factor alpha
- TYK, tyrosine kinase
- Th, T helper
- ZO, zona occludens
- hBD, human β-defensin
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Affiliation(s)
- Lisa A. Beck
- Department of Dermatology, University of Rochester Medical Center, Rochester, New York, USA,Correspondence: Lisa A. Beck, Department of Dermatology, University of Rochester Medical Center, 601 Elmwood Ave, Box 697, Rochester, New York 14642, USA.
| | - Michael J. Cork
- Sheffield Dermatology Research, Department of Infection, Immunity and Cardiovascular Disease (IICD), The University of Sheffield, The Medical School, Sheffield, United Kingdom
| | - Masayuki Amagai
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan,Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Anna De Benedetto
- Department of Dermatology, University of Rochester Medical Center, Rochester, New York, USA
| | - Kenji Kabashima
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto University, Kyoto, Japan
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21
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Chong AC, Chwa WJ, Ong PY. Aeroallergens in Atopic Dermatitis and Chronic Urticaria. Curr Allergy Asthma Rep 2022; 22:67-75. [PMID: 35362938 DOI: 10.1007/s11882-022-01033-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2022] [Indexed: 01/18/2023]
Abstract
PURPOSE OF REVIEW While aeroallergens are a well-established trigger of asthma and allergic rhinitis, their role in allergic skin diseases such as atopic dermatitis and chronic urticaria remains controversial. This paper reviews the pathophysiology and clinical evidence for aeroallergens in these allergic skin diseases and summarizes current strategies for evaluation and management. RECENT FINDINGS Current evidence implicates aeroallergens as triggers of cutaneous reactions in atopic dermatitis. Direct skin contact is the likely route of trigger. Aeroallergens may also trigger chronic urticaria, though mechanistic studies are limited. These allergens may cross the skin barrier and directly trigger neurons to release substance P, resulting in mast cell degranulation and dumping of histamine and prostaglandin D2. Many studies link aeroallergen sensitization to chronic urticaria, and case reports suggest the utility of avoidance strategies. The role of aeroallergens as a trigger is clear in atopic dermatitis and becoming emergent in chronic urticaria. Skin prick testing or serum-specific immunoglobulin E testing may be used to determine sensitivities. Management at this time centers on avoidance, and further studies are necessary to evaluate the efficacy of aeroallergen immunotherapy for both conditions.
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Affiliation(s)
- Albert C Chong
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Won Jong Chwa
- Saint Louis University School of Medicine, Saint Louis University, Saint Louis, MO, USA
| | - Peck Y Ong
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA. .,Division of Clinical Immunology and Allergy, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
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22
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Song A, Lee SE, Kim JH. Immunopathology and Immunotherapy of Inflammatory Skin Diseases. Immune Netw 2022; 22:e7. [PMID: 35291649 PMCID: PMC8901701 DOI: 10.4110/in.2022.22.e7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/20/2022] [Accepted: 01/23/2022] [Indexed: 12/01/2022] Open
Abstract
Recently, there have been impressive advancements in understanding of the immune mechanisms underlying cutaneous inflammatory diseases. To understand these diseases on a deeper level and clarify the therapeutic targets more precisely, numerous studies including in vitro experiments, animal models, and clinical trials have been conducted. This has resulted in a paradigm shift from non-specific suppression of the immune system to selective, targeted immunotherapies. These approaches target the molecular pathways and cytokines responsible for generating inflammatory conditions and reinforcing feedback mechanisms to aggravate inflammation. Among the numerous types of skin inflammation, psoriasis and atopic dermatitis (AD) are common chronic cutaneous inflammatory diseases. Psoriasis is a IL-17–mediated disease driven by IL-23, while AD is predominantly mediated by Th2 immunity. Autoimmune bullous diseases are autoantibody-mediated blistering disorders, including pemphigus and bullous pemphigoid. Alopecia areata is an organ-specific autoimmune disease mediated by CD8+ T-cells that targets hair follicles. This review will give an updated, comprehensive summary of the pathophysiology and immune mechanisms of inflammatory skin diseases. Moreover, the therapeutic potential of current and upcoming immunotherapies will be discussed.
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Affiliation(s)
- Ahreum Song
- Department of Dermatology, Gangnam Severance Hospital, Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Sang Eun Lee
- Department of Dermatology, Gangnam Severance Hospital, Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jong Hoon Kim
- Department of Dermatology, Gangnam Severance Hospital, Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seoul, Korea
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23
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Abe Y, Nishizawa M. Electrical aspects of skin as a pathway to engineering skin devices. APL Bioeng 2021; 5:041509. [PMID: 34849444 PMCID: PMC8604566 DOI: 10.1063/5.0064529] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/27/2021] [Indexed: 02/07/2023] Open
Abstract
Skin is one of the indispensable organs for life. The epidermis at the outermost surface provides a permeability barrier to infectious agents, chemicals, and excessive loss of water, while the dermis and subcutaneous tissue mechanically support the structure of the skin and appendages, including hairs and secretory glands. The integrity of the integumentary system is a key for general health, and many techniques have been developed to measure and control this protective function. In contrast, the effective skin barrier is the major obstacle for transdermal delivery and detection. Changes in the electrical properties of skin, such as impedance and ionic activity, is a practical indicator that reflects the structures and functions of the skin. For example, the impedance that reflects the hydration of the skin is measured for quantitative assessment in skincare, and the current generated across a wound is used for the evaluation and control of wound healing. Furthermore, the electrically charged structure of the skin enables transdermal drug delivery and chemical extraction. This paper provides an overview of the electrical aspects of the skin and summarizes current advances in the development of devices based on these features.
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Affiliation(s)
- Yuina Abe
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki-aza Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - Matsuhiko Nishizawa
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, 6-6-01 Aramaki-aza Aoba, Aoba-ku, Sendai 980-8579, Japan
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24
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How dendritic cells sense and respond to viral infections. Clin Sci (Lond) 2021; 135:2217-2242. [PMID: 34623425 DOI: 10.1042/cs20210577] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 09/15/2021] [Accepted: 09/23/2021] [Indexed: 12/26/2022]
Abstract
The ability of dendritic cells (DCs) to sense viral pathogens and orchestrate a proper immune response makes them one of the key players in antiviral immunity. Different DC subsets have complementing functions during viral infections, some specialize in antigen presentation and cross-presentation and others in the production of cytokines with antiviral activity, such as type I interferons. In this review, we summarize the latest updates concerning the role of DCs in viral infections, with particular focus on the complex interplay between DC subsets and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Despite being initiated by a vast array of immune receptors, DC-mediated antiviral responses often converge towards the same endpoint, that is the production of proinflammatory cytokines and the activation of an adaptive immune response. Nonetheless, the inherent migratory properties of DCs make them a double-edged sword and often viral recognition by DCs results in further viral dissemination. Here we illustrate these various aspects of the antiviral functions of DCs and also provide a brief overview of novel antiviral vaccination strategies based on DCs targeting.
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25
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Hassoun D, Malard O, Barbarot S, Magnan A, Colas L. Type 2 immunity-driven diseases: Towards a multidisciplinary approach. Clin Exp Allergy 2021; 51:1538-1552. [PMID: 34617355 PMCID: PMC9292742 DOI: 10.1111/cea.14029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/23/2021] [Accepted: 09/08/2021] [Indexed: 12/31/2022]
Abstract
Asthma, atopic dermatitis and chronic rhinoconjunctivitis are highly heterogeneous. However, epidemiologic associations exist between phenotypic groups of patients. Atopic march is one such association but is not the only common point. Indeed, beyond such phenotypes, hallmarks of type 2 immunity have been found in these diseases involving immune dysregulation as well as environmental triggers and epithelial dysfunction. From the canonical Th2 cytokines (IL-4, IL-5, IL-13), new cellular and molecular actors arise, from the epithelium's alarmins to new innate immune cells. Their interactions are now better understood across the different environmental barriers, and slight differences appeared. In parallel, the development of type 2-targeting biotherapies not only raised hope to treat those diseases but also raised new questions regarding their true pathophysiological involvement. Here, we review the place of type 2 immunity in the different phenotypes of asthma, chronic rhinitis, chronic rhinosinusitis and atopic dermatitis, highlighting nuances between them. New hypotheses rising from the use of biotherapies will be discussed along with the uncertainties and unmet needs of this field.
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Affiliation(s)
- Dorian Hassoun
- CHU Nantes, CNRS, INSERM, l'institut du Thorax, Université de Nantes, Nantes, France
| | - Olivier Malard
- Department of Otorhinolaryngology and Head and Neck Surgery, Nantes University Hospital, Nantes, France
| | - Sébastien Barbarot
- Department of Dermatology, CHU Nantes, UMR 1280 PhAN, INRA, Nantes Université, Nantes, France
| | - Antoine Magnan
- INRAe UMR_S 0892, Hôpital Foch, Université de Versailles Saint-Quentin, Paris Saclay, France
| | - Luc Colas
- Plateforme Transversale d'Allergologie et d'Immunologie Clinique, Institut du Thorax, CHU de Nantes, Nantes, France.,INSERM, CHU Nantes, Centre de Recherche en Transplantation et Immunologie UMR1064, Nantes Université, ITUN, Nantes, France
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26
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Oh JS, Lee SJ, Choung SY. Lithospermum erythrorhizon Alleviates Atopic Dermatitis-like Skin Lesions by Restoring Immune Balance and Skin Barrier Function in 2.4-Dinitrochlorobenzene-Induced NC/Nga Mice. Nutrients 2021; 13:nu13093209. [PMID: 34579088 PMCID: PMC8470668 DOI: 10.3390/nu13093209] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 01/08/2023] Open
Abstract
The incidence of atopic dermatitis (AD), a disease characterized by an abnormal immune balance and skin barrier function, has increased rapidly in developed countries. This study investigated the anti-atopic effect of Lithospermum erythrorhizon (LE) using NC/Nga mice induced by 2,4-dinitrochlorobenzene. LE reduced AD clinical symptoms, including inflammatory cell infiltration, epidermal thickness, ear thickness, and scratching behavior, in the mice. Additionally, LE reduced serum IgE and histamine levels, and restored the T helper (Th) 1/Th2 immune balance through regulation of the IgG1/IgG2a ratio. LE also reduced the levels of AD-related cytokines and chemokines, including interleukin (IL)-1β, IL-4, IL-6, tumor necrosis factor-α (TNF-α), thymic stromal lymphopoietin, thymus and activation-regulated chemokine, macrophage-derived chemokine, regulated on activation, normal T cell expressed and secreted, and monocyte chemoattractant protein-1 in the serum. Moreover, LE modulated AD-related cytokines and chemokines expressed and secreted by Th1, Th2, Th17, and Th22 cells in the dorsal skin and splenocytes. Furthermore, LE restored skin barrier function by increasing pro-filaggrin gene expression and levels of skin barrier-related proteins filaggrin, involucrin, loricrin, occludin, and zonula occludens-1. These results suggest that LE is a potential therapeutic agent that can alleviate AD by modulating Th1/Th2 immune balance and restoring skin barrier function.
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Affiliation(s)
- Jin-Su Oh
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Korea;
| | | | - Se-Young Choung
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Korea;
- Department of Preventive Pharmacy and Toxicology, College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Korea
- Correspondence:
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27
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Immunohistopathological Analysis of Immunoglobulin E-Positive Epidermal Dendritic Cells with House Dust Mite Antigens in Naturally Occurring Skin Lesions of Adult and Elderly Patients with Atopic Dermatitis. Dermatopathology (Basel) 2021; 8:426-441. [PMID: 34563036 PMCID: PMC8482222 DOI: 10.3390/dermatopathology8030045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/09/2021] [Accepted: 08/12/2021] [Indexed: 11/17/2022] Open
Abstract
The immunopathogenic role of house dust mite (HDM) allergens in the development of skin lesions in atopic dermatitis (AD) has not yet been precisely clarified. We immunohistopathologically evaluated the localization of immunoglobulin E (IgE)-positive epidermal dendritic cells with HDM antigens in the skin lesions of patients with IgE-allergic AD. Using double-immunofluorescence and single-immunochemical staining methods, we analyzed biopsy specimens from the skin lesions of six patients with IgE-allergic AD and HDM allergy and 11 control subjects with inflammatory skin disorders. Inflammatory dendritic epidermal cells (IDECs; CD11c+ and CD206+ cells) were markedly observed in the central area of the spongiotic epidermis of skin lesions in all AD patients. Furthermore, IgE-positive IDECs with HDM antigens in the central areas of the spongiosis were found in four of the six (66.7%) AD patients. Langerhans cells (LCs; CD207+ cells) with HDM antigens were also observed in the peripheral areas of the spongiosis. Infiltration of CD4+ and CD8+ T cells in association with IgE-positive IDECs and LCs with HDM antigens was seen in the spongiotic epidermis. An IgE-mediated delayed-type hypersensitivity reaction, in combination with IgE-bearing dendritic cells, specific T cells, keratinocytes, and HDM antigens, may lead to spongiotic tissue formation in eczematous dermatitis in AD.
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28
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IL-37 Targets TSLP-Primed Basophils to Alleviate Atopic Dermatitis. Int J Mol Sci 2021; 22:ijms22147393. [PMID: 34299012 PMCID: PMC8304334 DOI: 10.3390/ijms22147393] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/05/2021] [Accepted: 07/08/2021] [Indexed: 12/13/2022] Open
Abstract
Atopic dermatitis (AD) represents a severe global burden on physical, physiological and mental health. Innate immune cell basophils are essential for provoking allergic inflammation in AD. However, the roles of novel immunoregulatory cytokine IL-37 in basophils remain elusive. We employed in vitro co-culture of human basophils and human keratinocyte HaCaT cells and an in vivo MC903-induced AD murine model to investigate the anti-inflammatory mechanism of IL-37. In the in vitro model, IL-37b significantly decreased Der p1-induced thymic stromal lymphopoietin (TSLP) overexpression in HaCaT cells and decreased the expression of TSLP receptor as well as basophil activation marker CD203c on basophils. IL-37 could also reduce Th2 cytokine IL-4 release from TSLP-primed basophils ex vivo. In the in vivo model, alternative depletion of basophils ameliorated AD symptoms and significantly lowered the Th2 cell and eosinophil populations in the ear and spleen of the mice. Blocking TSLP alleviated the AD-like symptoms and reduced the infiltration of basophils in the spleen. In CRISPR/Cas9 human IL-37b knock-in mice or mice with direct treatment by human IL-37b antibody, AD symptoms including ear swelling and itching were significantly alleviated upon MC903 challenge. Notably, IL-37b presence significantly reduced the basophil infiltration in ear lesions. In summary, IL-37b could regulate the TSLP-mediated activation of basophils and reduce the release of IL-4. The results, therefore, suggest that IL-37 may target TSLP-primed basophils to alleviate AD.
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29
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Mancuso JB, Lee SS, Paller AS, Ohya Y, Eichenfield LF. Management of Severe Atopic Dermatitis in Pediatric Patients. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY-IN PRACTICE 2021; 9:1462-1471. [PMID: 33838839 DOI: 10.1016/j.jaip.2021.02.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 02/05/2021] [Accepted: 02/05/2021] [Indexed: 12/13/2022]
Abstract
Atopic dermatitis is a common, chronic inflammatory skin disorder, present in about 12% of children worldwide. Optimizing management of severe atopic dermatitis in pediatric patients is critical to reduce signs of inflammation, alleviate pruritus and sleep disturbance, minimize the development and/or impact of comorbidities, and improve the patient and caregiver's quality of life. Evaluating the longitudinal severity of pediatric atopic dermatitis is an important component of measuring therapeutic response and long-term management, and is different in clinical practice versus clinical trials. This article describes when and how to use different treatments for pediatric patients with severe atopic dermatitis, including topical medications, phototherapy, and systemic medical therapies (traditional immunosuppressants, biologics, and small molecule inhibitors). It also provides recommendations useful in clinical practice for nonpharmacologic interventions for pediatric patients with severe atopic dermatitis.
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Affiliation(s)
- Jennifer B Mancuso
- Department of Dermatology, University of Michigan Medical School, Ann Arbor, Mich
| | - Stephanie S Lee
- Departments of Dermatology and Pediatrics, University of California San Diego, San Diego, Calif; Pediatric and Adolescent Dermatology, Rady Children's Hospital San Diego, San Diego, Calif
| | - Amy S Paller
- Department of Dermatology, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Yukihiro Ohya
- Allergy Center, National Center for Child Health and Development, Tokyo, Japan
| | - Lawrence F Eichenfield
- Departments of Dermatology and Pediatrics, University of California San Diego, San Diego, Calif; Pediatric and Adolescent Dermatology, Rady Children's Hospital San Diego, San Diego, Calif.
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30
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Park S, Matte-Martone C, Gonzalez DG, Lathrop EA, May DP, Pineda CM, Moore JL, Boucher JD, Marsh E, Schmitter-Sánchez A, Cockburn K, Markova O, Bellaïche Y, Greco V. Skin-resident immune cells actively coordinate their distribution with epidermal cells during homeostasis. Nat Cell Biol 2021; 23:476-484. [PMID: 33958758 DOI: 10.1038/s41556-021-00670-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 03/24/2021] [Indexed: 01/12/2023]
Abstract
Organs consist of multiple cell types that ensure proper architecture and function. How different cell types coexist and interact to maintain their homeostasis in vivo remains elusive. The skin epidermis comprises mostly epithelial cells, but also harbours Langerhans cells (LCs) and dendritic epidermal T cells (DETCs). Whether and how distributions of LCs and DETCs are regulated during homeostasis is unclear. Here, by tracking individual cells in the skin of live adult mice over time, we show that LCs and DETCs actively maintain a non-random spatial distribution despite continuous turnover of neighbouring basal epithelial cells. Moreover, the density of epithelial cells regulates the composition of LCs and DETCs in the epidermis. Finally, LCs require the GTPase Rac1 to maintain their positional stability, density and tiling pattern reminiscent of neuronal self-avoidance. We propose that these cellular mechanisms provide the epidermis with an optimal response to environmental insults.
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Affiliation(s)
- Sangbum Park
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA.,Institute for Quantitative Health Science and Engineering (IQ), Michigan State University, East Lansing, MI, USA.,Division of Dermatology, Department of Medicine, College of Human Medicine, Michigan State University, East Lansing, MI, USA.,Department of Pharmacology and Toxicology, College of Human Medicine, Michigan State University, East Lansing, MI, USA
| | | | - David G Gonzalez
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | | | - Dennis P May
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | | | - Jessica L Moore
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | | | - Edward Marsh
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Axel Schmitter-Sánchez
- Institute for Quantitative Health Science and Engineering (IQ), Michigan State University, East Lansing, MI, USA.,Cell and Molecular Biology Program, College of Natural Science, Michigan State University, East Lansing, MI, USA
| | - Katie Cockburn
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Olga Markova
- LadHyX, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
| | - Yohanns Bellaïche
- Génétique et Biologie du Développement, Institut Curie, Université PSL, CNRS UMR3215, INSERM U934, Paris, France
| | - Valentina Greco
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA. .,Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA. .,Department of Dermatology, Yale School of Medicine, New Haven, CT, USA. .,Yale Stem Cell Center, Yale School of Medicine, New Haven, CT, USA. .,Yale Cancer Center, Yale School of Medicine, New Haven, CT, USA.
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31
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Luger T, Paller AS, Irvine AD, Sidbury R, Eichenfield LF, Werfel T, Bieber T. Topical therapy of atopic dermatitis with a focus on pimecrolimus. J Eur Acad Dermatol Venereol 2021; 35:1505-1518. [PMID: 33834524 DOI: 10.1111/jdv.17272] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/16/2021] [Indexed: 12/12/2022]
Abstract
Atopic dermatitis (AD) is a chronic and relapsing, inflammatory skin disease characterized by impaired skin barrier function and immune system dysregulation that results in dryness, skin microbiome dysbiosis and intense pruritus. It is highly heterogeneous, and its management is demanding. Patients with AD are at greater risk of comorbidities such as attention-deficit hyperactivity disorder as well as other atopic diseases. Early-onset AD cases typically improve or resolve in late childhood; however, it is proposed that the prevalence of persistent or adult-onset AD is higher than previously thought. Basic therapy consists of emollient application and trigger avoidance, and when insufficient, topical corticosteroids (TCS) are the first-line treatment. However, corticophobia/steroid aversion and TCS side-effects, particularly on sensitive skin areas, lead to low compliance and insufficient disease control. Several long- and short-term randomized controlled and daily practice studies have demonstrated that topical calcineurin inhibitors, such as pimecrolimus, have similar anti-inflammatory effects to low-to-medium strength TCS, reduce pruritus and improve the quality of life of patients. In addition, pimecrolimus does not cause skin atrophy, is steroid-sparing and has a good safety profile, with no evidence for an increased risk of malignancies or skin infections. In general, pimecrolimus cream is well-accepted and well-tolerated, encouraging patient adherence and leading to its use by many physicians as a preferred therapy for children and sensitive skin areas.
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Affiliation(s)
- T Luger
- Department of Dermatology, University of Münster, Münster, Germany
| | - A S Paller
- Departments of Dermatology and Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - A D Irvine
- Pediatric Dermatology, Children's Health Ireland at Crumlin, Dublin, Ireland.,National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Dublin, Ireland.,Clinical Medicine, Trinity College Dublin, Dublin, Ireland
| | - R Sidbury
- University of Washington School of Medicine, Seattle, WA, USA.,Seattle Children's Hospital, Seattle, WA, USA
| | - L F Eichenfield
- Departments of Dermatology and Pediatrics, University of California, San Diego School of Medicine, Rady Children's Hospital, San Diego, CA, USA
| | - T Werfel
- Department of Dermatology, MHH, Hannover, Germany
| | - T Bieber
- Department of Dermatology and Allergy, Christine Kühne-Center for Allergy Research and Education, University Hospital, Bonn, Germany
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32
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Luger T, Amagai M, Dreno B, Dagnelie MA, Liao W, Kabashima K, Schikowski T, Proksch E, Elias PM, Simon M, Simpson E, Grinich E, Schmuth M. Atopic dermatitis: Role of the skin barrier, environment, microbiome, and therapeutic agents. J Dermatol Sci 2021; 102:142-157. [PMID: 34116898 DOI: 10.1016/j.jdermsci.2021.04.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 02/06/2023]
Abstract
Atopic dermatitis (AD) is a chronic, inflammatory skin disorder characterized by eczematous and pruritic skin lesions. In recent decades, the prevalence of AD has increased worldwide, most notably in developing countries. The enormous progress in our understanding of the complex composition and functions of the epidermal barrier allows for a deeper appreciation of the active role that the skin barrier plays in the initiation and maintenance of skin inflammation. The epidermis forms a physical, chemical, immunological, neuro-sensory, and microbial barrier between the internal and external environment. Not only lesional, but also non-lesional areas of AD skin display many morphological, biochemical and functional differences compared with healthy skin. Supporting this notion, genetic defects affecting structural proteins of the skin barrier, including filaggrin, contribute to an increased risk of AD. There is evidence to suggest that natural environmental allergens and man-made pollutants are associated with an increased likelihood of developing AD. A compromised epidermal barrier predisposes the skin to increased permeability of these compounds. Numerous topical and systemic therapies for AD are currently available or in development; while anti-inflammatory therapy is central to the treatment of AD, some existing and novel therapies also appear to exert beneficial effects on skin barrier function. Further research on the skin barrier, particularly addressing epidermal differentiation and inflammation, lipid metabolism, and the role of bacterial communities for skin barrier function, will likely expand our understanding of the complex etiology of AD and lead to identification of novel targets and the development of new therapies.
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Affiliation(s)
- Thomas Luger
- Department of Dermatology, University of Münster, Münster, Germany.
| | - Masayuki Amagai
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan; Laboratory for Skin Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Brigitte Dreno
- Dermatology Department, Nantes University, CHU Nantes, CIC 1413, CRCINA, Nantes, France
| | - Marie-Ange Dagnelie
- Dermatology Department, Nantes University, CHU Nantes, CIC 1413, CRCINA, Nantes, France
| | - Wilson Liao
- Department of Dermatology, University of California, San Francisco, CA, United States
| | - Kenji Kabashima
- Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tamara Schikowski
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | | | - Peter M Elias
- San Francisco VA Medical Center, University of California, San Francisco, CA, United States
| | - Michel Simon
- UDEAR, Inserm, University of Toulouse, U1056, Toulouse, France
| | - Eric Simpson
- Department of Dermatology, Oregon Health & Science University, Portland, OR, United States
| | - Erin Grinich
- Department of Dermatology, Oregon Health & Science University, Portland, OR, United States
| | - Matthias Schmuth
- Department of Dermatology, Medical University Innsbruck, Innsbruck, Austria
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33
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Leung DYM, Berdyshev E, Goleva E. Cutaneous barrier dysfunction in allergic diseases. J Allergy Clin Immunol 2021; 145:1485-1497. [PMID: 32507227 DOI: 10.1016/j.jaci.2020.02.021] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/13/2020] [Accepted: 02/14/2020] [Indexed: 01/08/2023]
Abstract
The fundamental defect(s) that drives atopic dermatitis (AD) remains controversial. "Outside in" proponents point to the important association of filaggrin gene mutations and other skin barrier defects with AD. The "inside out" proponents derive support from evidence that AD occurs in genetic animal models with overexpression of type 2 immune pathways in their skin, and humans with gain-of-function mutations in their type 2 response develop severe AD. The observation that therapeutic biologics, targeting type 2 immune responses, can reverse AD provides compelling support for the importance of "inside out" mechanisms of AD. In this review, we propose a central role for epithelial cell dysfunction that accounts for the dual role of skin barrier defects and immune pathway activation in AD. The complexity of AD has its roots in the dysfunction of the epithelial barrier that allows the penetration of allergens, irritants, and microbes into a cutaneous milieu that facilitates the induction of type 2 immune responses. The AD phenotypes and endotypes that result in chronic skin inflammation and barrier dysfunction are modified by genes, innate/adaptive immune responses, and different environmental factors that cause skin barrier dysfunction. There is also compelling evidence that skin barrier dysfunction can alter the course of childhood asthma, food allergy, and allergic rhinosinusitis. Effective management of AD requires a multipronged approach, not only restoring cutaneous barrier function, microbial flora, and immune homeostasis but also enhancing skin epithelial differentiation.
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Affiliation(s)
| | | | - Elena Goleva
- Department of Pediatrics, National Jewish Health, Denver, Colo
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34
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Abstract
The high expression of CD1a on Langerhans cells in normal human skin suggests a central role for this lipid antigen presenting molecule in skin homeostasis and immunity. Although the lipid antigen presenting function of CD1a has been known for years, the physiological and pathological functions of the CD1a system in human skin remain incompletely understood. This review provides an overview of this active area of investigation, and discusses recent insights into the functions of CD1a, CD1a-restricted T cells, and lipid antigens in inflammatory and allergic skin disease. We include recent publications and work presented at the biennial CD1-MR1 EMBO workshop held in 2019 in Oxford, regarding lipids that increase and those that decrease T cell responses to CD1a.
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Affiliation(s)
- Annemieke de Jong
- Department of Dermatology, Columbia University Irving Medical Center, New York, NY, USA.
| | - Graham Ogg
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
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35
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Wall Teichoic Acid in Staphylococcus aureus Host Interaction. Trends Microbiol 2020; 28:985-998. [DOI: 10.1016/j.tim.2020.05.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 02/07/2023]
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36
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Emmert H, Baurecht H, Thielking F, Stölzl D, Rodriguez E, Harder I, Proksch E, Weidinger S. Stratum corneum lipidomics analysis reveals altered ceramide profile in atopic dermatitis patients across body sites with correlated changes in skin microbiome. Exp Dermatol 2020; 30:1398-1408. [PMID: 32885529 DOI: 10.1111/exd.14185] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/24/2020] [Accepted: 08/24/2020] [Indexed: 12/24/2022]
Abstract
BACKGROUND Atopic dermatitis (AD) is driven by the interplay between a dysfunctional epidermal barrier and a skewed cutaneous immune dysregulation. As part of the complex skin barrier dysfunction, abnormalities in lipid organization and microbiome composition have been described. We set out to systematically investigate the composition of the stratum corneum lipidome, skin microbiome and skin physiology parameters at three different body sites in patients with AD and healthy volunteers. METHODS We analysed tape strips from different body areas obtained from 10 adults with AD and 10 healthy volunteers matched for FLG mutation status for 361 skin lipid species using the Metabolon mass spectrometry platform. 16S rRNA data were available from all probands. RESULTS Our study showed that the lipid composition differs significantly between body sites and between AD patients and healthy individuals. Ceramide species NS was significantly higher in AD patients compared to healthy volunteers and was also higher in AD patients with a FLG mutation compared to AD patients without a FLG mutation. The correlation analysis of skin lipid alterations with the microbiome showed that Staphylococcus colonization in AD is positively correlated with ceramide subspecies AS, ADS, NS and NDS. CONCLUSION This is the first study to reveal site-specific lipid alterations and correlations with the skin microbiome in AD.
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Affiliation(s)
- Hila Emmert
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Hansjörg Baurecht
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany.,Department of Epidemiology and Preventive Medicine, University of Regensburg, Regensburg, Germany
| | - Frederieke Thielking
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Dora Stölzl
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Elke Rodriguez
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Inken Harder
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Ehrhardt Proksch
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Stephan Weidinger
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
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37
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Abstract
Atopic dermatitis is a common inflammatory skin disorder characterised by recurrent eczematous lesions and intense itch. The disorder affects people of all ages and ethnicities, has a substantial psychosocial impact on patients and relatives, and is the leading cause of the global burden from skin disease. Atopic dermatitis is associated with increased risk of multiple comorbidities, including food allergy, asthma, allergic rhinitis, and mental health disorders. The pathophysiology is complex and involves a strong genetic predisposition, epidermal dysfunction, and T-cell driven inflammation. Although type-2 mechanisms are dominant, there is increasing evidence that the disorder involves multiple immune pathways. Currently, there is no cure, but increasing numbers of innovative and targeted therapies hold promise for achieving disease control, including in patients with recalcitrant disease. We summarise and discuss advances in our understanding of the disease and their implications for prevention, management, and future research.
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Affiliation(s)
- Sinéad M Langan
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, UK; St John's Institute of Dermatology, Guy's and St Thomas' NHS Foundation Trust, London, UK; Health Data Research UK, London, UK.
| | - Alan D Irvine
- Department of Clinical Medicine, Trinity College Dublin, Dublin, Ireland; Dermatology, Children's Health Ireland, Crumlin, Ireland; National Children's Research Centre, Dublin, Ireland
| | - Stephan Weidinger
- Department of Dermatology and Allergy, University Hospital Schleswig-Holstein, Kiel, Germany
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38
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Gorzelanny C, Mess C, Schneider SW, Huck V, Brandner JM. Skin Barriers in Dermal Drug Delivery: Which Barriers Have to Be Overcome and How Can We Measure Them? Pharmaceutics 2020; 12:E684. [PMID: 32698388 PMCID: PMC7407329 DOI: 10.3390/pharmaceutics12070684] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/11/2020] [Accepted: 07/14/2020] [Indexed: 12/13/2022] Open
Abstract
Although, drugs are required in the various skin compartments such as viable epidermis, dermis, or hair follicles, to efficiently treat skin diseases, drug delivery into and across the skin is still challenging. An improved understanding of skin barrier physiology is mandatory to optimize drug penetration and permeation. The various barriers of the skin have to be known in detail, which means methods are needed to measure their functionality and outside-in or inside-out passage of molecules through the various barriers. In this review, we summarize our current knowledge about mechanical barriers, i.e., stratum corneum and tight junctions, in interfollicular epidermis, hair follicles and glands. Furthermore, we discuss the barrier properties of the basement membrane and dermal blood vessels. Barrier alterations found in skin of patients with atopic dermatitis are described. Finally, we critically compare the up-to-date applicability of several physical, biochemical and microscopic methods such as transepidermal water loss, impedance spectroscopy, Raman spectroscopy, immunohistochemical stainings, optical coherence microscopy and multiphoton microscopy to distinctly address the different barriers and to measure permeation through these barriers in vitro and in vivo.
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Affiliation(s)
| | | | | | | | - Johanna M. Brandner
- Department of Dermatology and Venerology, Center for Internal Medicine, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; (C.G.); (C.M.); (S.W.S.); (V.H.)
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39
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Mnich ME, van Dalen R, van Sorge NM. C-Type Lectin Receptors in Host Defense Against Bacterial Pathogens. Front Cell Infect Microbiol 2020; 10:309. [PMID: 32733813 PMCID: PMC7358460 DOI: 10.3389/fcimb.2020.00309] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/22/2020] [Indexed: 12/11/2022] Open
Abstract
Antigen-presenting cells (APCs) are present throughout the human body—in tissues, at barrier sites and in the circulation. They are critical for processing external signals to instruct both local and systemic responses toward immune tolerance or immune defense. APCs express an extensive repertoire of pattern-recognition receptors (PRRs) to detect and transduce these signals. C-type lectin receptors (CLRs) comprise a subfamily of PRRs dedicated to sensing glycans, including those expressed by commensal and pathogenic bacteria. This review summarizes recent findings on the recognition of and responses to bacteria by membrane-expressed CLRs on different APC subsets, which are discussed according to the primary site of infection. Many CLR-bacterial interactions promote bacterial clearance, whereas other interactions are exploited by bacteria to enhance their pathogenic potential. The discrimination between protective and virulence-enhancing interactions is essential to understand which interactions to target with new prophylactic or treatment strategies. CLRs are also densely concentrated at APC dendrites that sample the environment across intact barrier sites. This suggests an–as yet–underappreciated role for CLR-mediated recognition of microbiota-produced glycans in maintaining tolerance at barrier sites. In addition to providing a concise overview of identified CLR-bacteria interactions, we discuss the main challenges and potential solutions for the identification of new CLR-bacterial interactions, including those with commensal bacteria, and for in-depth structure-function studies on CLR-bacterial glycan interactions. Finally, we highlight the necessity for more relevant tissue-specific in vitro, in vivo and ex vivo models to develop therapeutic applications in this area.
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Affiliation(s)
- Malgorzata E Mnich
- Medical Microbiology, UMC Utrecht, Utrecht University, Utrecht, Netherlands.,GSK, Siena, Italy
| | - Rob van Dalen
- Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Nina M van Sorge
- Department of Medical Microbiology and Infection Prevention, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, Netherlands.,Netherlands Reference Laboratory for Bacterial Meningitis, Amsterdam University Medical Center, Amsterdam, Netherlands
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40
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Selective AhR knockout in langerin-expressing cells abates Langerhans cells and polarizes Th2/Tr1 in epicutaneous protein sensitization. Proc Natl Acad Sci U S A 2020; 117:12980-12990. [PMID: 32461368 DOI: 10.1073/pnas.1917479117] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) represents an environmental sensor regulating immune responses. In the skin, AhR is expressed in several cell types, including keratinocytes, epidermal Langerhans cells (LC), and dermal dendritic cells (DC). The mechanisms how AhR activates or inhibits cutaneous immune responses remain controversial, owing to differences in the cell-specific functions of AhR and the different activating ligands. Therefore, we sought to investigate the role of AhR in LC and langerin+ and negative DC in the skin. To this aim, we generated Langerin-specific and CD11c-specific knockout (-/-) mice lacking AhR, respectively, in LC and Langerin+ dermal DC and in all CD11c+ cells. These were then tested in an epicutaneous protein (ovalbumin, Ova) sensitization model. Immunofluorescence microscopy and flow cytometry revealed that Langerin-AhR-/- but not CD11c-AhR-/- mice harbored a decreased number of LC with fewer and stunted dendrites in the epidermis as well as a decreased number of LC in skin-draining lymph nodes (LN). Moreover, in the absence of AhR, we detected an enhanced T helper type-2 (Th2) [increased interleukin 5 (IL-5) and interleukin 13 (IL-13)] and T regulatory type-1 (Tr1) (IL-10) response when LN cells were challenged with Ova in vitro, though the number of regulatory T cells (Treg) in the LN remained comparable. Langerin-AhR-/- mice also exhibited increased blood levels of Ova-specific immunoglobulin E (IgE). In conclusion, deletion of AhR in langerin-expressing cells diminishes the number and activation of LC, while enhancing Th2 and Tr1 responses upon epicutaneous protein sensitization.
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Campolo M, Casili G, Paterniti I, Filippone A, Lanza M, Ardizzone A, Scuderi SA, Cuzzocrea S, Esposito E. Effect of a Product Containing Xyloglucan and Pea Protein on a Murine Model of Atopic Dermatitis. Int J Mol Sci 2020; 21:ijms21103596. [PMID: 32438777 PMCID: PMC7279434 DOI: 10.3390/ijms21103596] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/23/2020] [Accepted: 05/17/2020] [Indexed: 12/12/2022] Open
Abstract
Atopic dermatitis (AD) is a chronic inflammatory disease of the skin, characterized by dryness and more or less severe itching. The etiology of AD is complex and has not been fully clarified, involving genetic susceptibility, immunological abnormalities, epidermal barrier dysfunction, and environmental factors. Xyloglucan (XG) and pea protein (PP) are two compounds of natural origin characterized by the ability to create a physical barrier that protects mucosae membranes, reducing inflammation. The aim of the present study was to evaluate the potential beneficial effects of XG + PP in both a mouse model of AD and Staphylococcus aureus (S. aureus) infection- associated AD. Mice were topically treated with 200 μL of 0.5% oxazolone on the dorsal skin three times a week for AD induction. Mice received XG and PP by topical administration 1 h before oxazolone treatment. In S. aureus infection-associated AD, to induce a superficial superinfection of the skin, mice were also treated with 5 μL of 108 of a culture of S. aureus for 2 weeks; mice superinfected received XG and PP by topical administration 1 h before oxazolone + S. aureus. Four weeks later, the skin was removed for histological and biochemical analysis. Our results demonstrated the protective barrier effects of XG and PP characterized by a reduction in histological tissue changes, mastocyte degranulation, and tight junction permeability in the skin following oxazolone treatment. Moreover, XG + PP was able to preserve filaggrin expression, a hallmark of AD. Our data also support the effectiveness of XG + PP to reduce the damage by superinfection post AD induced by S. aureus. In conclusion, a future product containing XG and PP could be considered as a potentially interesting approach for the treatment of AD.
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Iwamoto H, Matsubara T, Okamoto T, Yoshikawa M, Matsumoto T, Kono G, Takeda Y. Epicutaneous immunogenicity of partially hydrolyzed whey protein evaluated using tape-stripped mouse model. Pediatr Allergy Immunol 2020; 31:388-395. [PMID: 31943412 DOI: 10.1111/pai.13211] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 12/13/2019] [Accepted: 12/24/2019] [Indexed: 01/10/2023]
Abstract
BACKGROUND Hydrolyzed cow's milk protein formulas are widely used for infants with a history or risk of cow's milk allergy. Based on the current theory that food allergen sensitization occurs via the skin, we investigated the epicutaneous immunogenicity of partially hydrolyzed whey proteins, which are ingredients in infant formulas. METHODS BALB/c mice were exposed epicutaneously to whey protein concentrate (WPC) or partial whey protein hydrolysates (PWH1 or PWH2) on tape-stripped skin. Sensitization was assessed by evaluating serum β-lactoglobulin (β-LG)-specific antibodies, basophil activation, and cytokine production from β-LG-stimulated lymphoid cells. The anaphylaxis reaction was evaluated by measuring the rectal temperature and plasma level of mouse mast cell protease-1 after oral β-LG challenge. Immune cell accumulation in the skin was also analyzed. RESULTS Substantive sensitization and β-LG-induced anaphylaxis reaction were observed in WPC-exposed mice, whereas no significant changes were observed in PWH1- or PWH2-exposed mice. The basophil and eosinophil counts increased in WPC-exposed murine skin, not but in PWH1- or PWH2-exposed mice. CONCLUSION The epicutaneous immunogenicity of PWH1 and PWH2 is markedly decreased, which may reduce the risk of allergen sensitization. Further studies are required to investigate the clinical value of these partial hydrolysates for high-risk infants.
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Affiliation(s)
- Hiroshi Iwamoto
- Wellness & Nutrition Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
| | - Takeshi Matsubara
- Wellness & Nutrition Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
| | - Tomoyuki Okamoto
- Wellness & Nutrition Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
| | - Mayu Yoshikawa
- Wellness & Nutrition Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
| | - Takuya Matsumoto
- Wellness & Nutrition Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
| | - Gaku Kono
- Wellness & Nutrition Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
| | - Yasuhiro Takeda
- Wellness & Nutrition Science Institute, Morinaga Milk Industry Co., Ltd., Zama, Japan
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Schafer PH, Adams M, Horan G, Truzzi F, Marconi A, Pincelli C. Apremilast Normalizes Gene Expression of Inflammatory Mediators in Human Keratinocytes and Reduces Antigen-Induced Atopic Dermatitis in Mice. Drugs R D 2020; 19:329-338. [PMID: 31598889 PMCID: PMC6890576 DOI: 10.1007/s40268-019-00284-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Background Apremilast, an oral phosphodiesterase (PDE) 4 inhibitor, has demonstrated efficacy in psoriasis, while its efficacy in atopic dermatitis (AD) was found to be modest. AD is a chronic inflammatory skin disease associated with activation of T helper (Th) 2 and Th17 immunity and a compromised epidermal barrier. Objective The objectives of this study were to examine the expression of PDE4 isoforms in skin from healthy subjects and AD patients, and to determine the effects of apremilast on AD-related inflammatory markers in vitro and in murine models of AD. Methods The expression of PDE4 isoforms (A, B, C, and D) in skin biopsies from healthy subjects and AD patients was evaluated using immunohistochemistry and digital image analysis. Using quantitative real-time reverse-transcriptase polymerase chain reaction, we evaluated the effects of apremilast on gene expression in adult human epidermal keratinocytes (HEKa) stimulated by Th2 and Th17 cytokines, and in two mouse models of antigen-induced AD. Results Expression of PDE4 isoforms increased up to three-fold in the epidermis of AD patients versus healthy skin. In interleukin (IL)-4 and IL-17-stimulated HEKa cells, apremilast significantly changed the expression of ILs, including IL-12/IL-23p40 and IL-31, and alarmins S100A7, S100A8, and S100A12. In mouse models of AD, apremilast significantly reduced ear swelling and monocyte chemoattractant protein-1 expression. Conclusion PDE4 is overexpressed in AD skin compared with normal skin, and inflammatory gene expression by human keratinocytes and mouse dermatitis can be modulated by apremilast.
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Affiliation(s)
- Peter H Schafer
- Sol J. Barer Laboratories, Department of Translational Development, Celgene Corporation, 181 Passaic Avenue, Summit, NJ, 07901, USA.
| | - Mary Adams
- Sol J. Barer Laboratories, Department of Translational Development, Celgene Corporation, 181 Passaic Avenue, Summit, NJ, 07901, USA
| | - Gerald Horan
- Sol J. Barer Laboratories, Department of Translational Development, Celgene Corporation, 181 Passaic Avenue, Summit, NJ, 07901, USA
| | - Francesca Truzzi
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Alessandra Marconi
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Carlo Pincelli
- Laboratory of Cutaneous Biology, Department of Surgical, Medical, Dental and Morphological Sciences, University of Modena and Reggio Emilia, Modena, Italy
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Claudin-1 decrease impacts epidermal barrier function in atopic dermatitis lesions dose-dependently. Sci Rep 2020; 10:2024. [PMID: 32029783 PMCID: PMC7004991 DOI: 10.1038/s41598-020-58718-9] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 01/17/2020] [Indexed: 12/15/2022] Open
Abstract
The transmembrane protein claudin-1 is a major component of epidermal tight junctions (TJs), which create a dynamic paracellular barrier in the epidermis. Claudin-1 downregulation has been linked to atopic dermatitis (AD) pathogenesis but variable levels of claudin-1 have also been observed in healthy skin. To elucidate the impact of different levels of claudin-1 in healthy and diseased skin we determined claudin-1 levels in AD patients and controls and correlated them to TJ and skin barrier function. We observed a strikingly broad range of claudin-1 levels with stable TJ and overall skin barrier function in healthy and non-lesional skin. However, a significant decrease in TJ barrier function was detected in lesional AD skin where claudin-1 levels were further reduced. Investigations on reconstructed human epidermis expressing different levels of claudin-1 revealed that claudin-1 levels correlated with inside-out and outside-in barrier function, with a higher coherence for smaller molecular tracers. Claudin-1 decrease induced keratinocyte-autonomous IL-1β expression and fostered inflammatory epidermal responses to non-pathogenic Staphylococci. In conclusion, claudin-1 decrease beyond a threshold level results in TJ and epidermal barrier function impairment and induces inflammation in human epidermis. Increasing claudin-1 levels might improve barrier function and decrease inflammation and therefore be a target for AD treatment.
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45
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Fujii M. Current Understanding of Pathophysiological Mechanisms of Atopic Dermatitis: Interactions among Skin Barrier Dysfunction, Immune Abnormalities and Pruritus. Biol Pharm Bull 2020; 43:12-19. [DOI: 10.1248/bpb.b19-00088] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Masanori Fujii
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University
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46
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Roach KA, Stefaniak AB, Roberts JR. Metal nanomaterials: Immune effects and implications of physicochemical properties on sensitization, elicitation, and exacerbation of allergic disease. J Immunotoxicol 2019; 16:87-124. [PMID: 31195861 PMCID: PMC6649684 DOI: 10.1080/1547691x.2019.1605553] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 03/15/2019] [Accepted: 04/05/2019] [Indexed: 12/25/2022] Open
Abstract
The recent surge in incorporation of metallic and metal oxide nanomaterials into consumer products and their corresponding use in occupational settings have raised concerns over the potential for metals to induce size-specific adverse toxicological effects. Although nano-metals have been shown to induce greater lung injury and inflammation than their larger metal counterparts, their size-related effects on the immune system and allergic disease remain largely unknown. This knowledge gap is particularly concerning since metals are historically recognized as common inducers of allergic contact dermatitis, occupational asthma, and allergic adjuvancy. The investigation into the potential for adverse immune effects following exposure to metal nanomaterials is becoming an area of scientific interest since these characteristically lightweight materials are easily aerosolized and inhaled, and their small size may allow for penetration of the skin, which may promote unique size-specific immune effects with implications for allergic disease. Additionally, alterations in physicochemical properties of metals in the nano-scale greatly influence their interactions with components of biological systems, potentially leading to implications for inducing or exacerbating allergic disease. Although some research has been directed toward addressing these concerns, many aspects of metal nanomaterial-induced immune effects remain unclear. Overall, more scientific knowledge exists in regards to the potential for metal nanomaterials to exacerbate allergic disease than to their potential to induce allergic disease. Furthermore, effects of metal nanomaterial exposure on respiratory allergy have been more thoroughly-characterized than their potential influence on dermal allergy. Current knowledge regarding metal nanomaterials and their potential to induce/exacerbate dermal and respiratory allergy are summarized in this review. In addition, an examination of several remaining knowledge gaps and considerations for future studies is provided.
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Affiliation(s)
- Katherine A Roach
- a Allergy and Clinical Immunology Branch (ACIB) , National Institute of Occupational Safety and Health (NIOSH) , Morgantown , WV , USA
- b School of Pharmacy , West Virginia University , Morgantown , WV , USA
| | - Aleksandr B Stefaniak
- c Respiratory Health Division (RHD) , National Institute of Occupational Safety and Health (NIOSH) , Morgantown , WV , USA
| | - Jenny R Roberts
- a Allergy and Clinical Immunology Branch (ACIB) , National Institute of Occupational Safety and Health (NIOSH) , Morgantown , WV , USA
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47
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Simon D, Simon HU. Relationship of skin barrier breakdown and eosinophilic esophagitis. J Allergy Clin Immunol 2019; 145:90-92.e1. [PMID: 31738992 DOI: 10.1016/j.jaci.2019.11.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/06/2019] [Accepted: 11/12/2019] [Indexed: 12/23/2022]
Affiliation(s)
- Dagmar Simon
- Department of Dermatology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Bern, Switzerland; Department of Clinical Immunology and Allergology, Sechenov University, Moscow, Russia
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48
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Luo Y, Wang S, Liu X, Wen H, Li W, Yao X. Langerhans cells mediate the skin-induced tolerance to ovalbumin via Langerin in a murine model. Allergy 2019; 74:1738-1747. [PMID: 30964950 DOI: 10.1111/all.13813] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 02/18/2019] [Accepted: 03/16/2019] [Indexed: 12/28/2022]
Abstract
BACKGROUND Epicutaneous sensitization is an important route of immunization for allergens in atopic diseases; however, studies have also shown that application with protein on the intact skin induces antigen-specific tolerance. Langerhans cells (LCs) play an immunosuppressive role in several inflammatory skin diseases and mouse models, and the role of LCs in the skin-induced tolerance is not fully understood. METHODS Langerin-DTA mice that were deficient in LCs were utilized to produce the model of skin-induced tolerance to ovalbumin (OVA). Binding of Langerin to OVA was analyzed by enzyme-linked immunosorbent assay, flow cytometry, and immunofluorescence. Homozygous Langerin-DTR mice that were deficient in Langerin were introduced to assess the role of Langerin in the skin-induced tolerance. RESULTS Application with OVA onto the intact, but not tape-stripped, skin attenuated the production of OVA-specific IgE, IgG1, and IgG2a induced by subsequent subcutaneous immunization with OVA, and the inhibitory effects were abolished in Langerin-DTA mice. In contrast to the tape-stripped skin, the intact skin induced the production of IL-10 by LCs in draining lymph node after application with OVA. Langerin could bind OVA, and homozygous Langerin-DTR mice demonstrated similar humoral and cellular immune responses in the model of skin-induced tolerance compared to wide-type mice. CONCLUSION Our data suggested that LCs were critical in the intact skin-induced tolerance to protein antigen via Langerin, and LCs might be targeted via Langerin to regulate the immune responses in systemic and (or) skin inflammatory diseases.
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Affiliation(s)
- Yang Luo
- Institute of Dermatology Chinese Academy of Medical Sciences and Peking Union Medical College Nanjing China
| | - Su Wang
- Institute of Dermatology Chinese Academy of Medical Sciences and Peking Union Medical College Nanjing China
| | - Xiaochun Liu
- Institute of Dermatology Chinese Academy of Medical Sciences and Peking Union Medical College Nanjing China
| | - He Wen
- Institute of Dermatology Chinese Academy of Medical Sciences and Peking Union Medical College Nanjing China
| | - Wei Li
- Department of Dermatology, Huashan Hospital Fudan University Shanghai China
| | - Xu Yao
- Institute of Dermatology Chinese Academy of Medical Sciences and Peking Union Medical College Nanjing China
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Minzaghi D, Pavel P, Dubrac S. Xenobiotic Receptors and Their Mates in Atopic Dermatitis. Int J Mol Sci 2019; 20:E4234. [PMID: 31470652 PMCID: PMC6747412 DOI: 10.3390/ijms20174234] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/19/2019] [Accepted: 08/26/2019] [Indexed: 02/07/2023] Open
Abstract
Atopic dermatitis (AD) is the most common inflammatory skin disease worldwide. It is a chronic, relapsing and pruritic skin disorder which results from epidermal barrier abnormalities and immune dysregulation, both modulated by environmental factors. AD is strongly associated with asthma and allergic rhinitis in the so-called 'atopic march.' Xenobiotic receptors and their mates are ligand-activated transcription factors expressed in the skin where they control cellular detoxification pathways. Moreover, they regulate the expression of genes in pathways involved in AD in epithelial cells and immune cells. Activation or overexpression of xenobiotic receptors in the skin can be deleterious or beneficial, depending on context, ligand and activation duration. Moreover, their impact on skin might be amplified by crosstalk among xenobiotic receptors and their mates. Because they are activated by a broad range of endogenous molecules, drugs and pollutants owing to their promiscuous ligand affinity, they have recently crystalized the attention of researchers, including in dermatology and especially in the AD field. This review examines the putative roles of these receptors in AD by critically evaluating the conditions under which the proteins and their ligands have been studied. This information should provide new insights into AD pathogenesis and ways to develop new therapeutic interventions.
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Affiliation(s)
- Deborah Minzaghi
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Petra Pavel
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Sandrine Dubrac
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, 6020 Innsbruck, Austria.
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50
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Bertram KM, Botting RA, Baharlou H, Rhodes JW, Rana H, Graham JD, Patrick E, Fletcher J, Plasto TM, Truong NR, Royle C, Doyle CM, Tong O, Nasr N, Barnouti L, Kohout MP, Brooks AJ, Wines MP, Haertsch P, Lim J, Gosselink MP, Ctercteko G, Estes JD, Churchill MJ, Cameron PU, Hunter E, Haniffa MA, Cunningham AL, Harman AN. Identification of HIV transmitting CD11c + human epidermal dendritic cells. Nat Commun 2019; 10:2759. [PMID: 31227717 PMCID: PMC6588576 DOI: 10.1038/s41467-019-10697-w] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 05/24/2019] [Indexed: 11/10/2022] Open
Abstract
Langerhans cells (LC) are thought to be the only mononuclear phagocyte population in the epidermis where they detect pathogens. Here, we show that CD11c+ dendritic cells (DCs) are also present. These cells are transcriptionally similar to dermal cDC2 but are more efficient antigen-presenting cells. Compared to LCs, epidermal CD11c+ DCs are enriched in anogenital tissues where they preferentially interact with HIV, express the higher levels of HIV entry receptor CCR5, support the higher levels of HIV uptake and replication and are more efficient at transmitting the virus to CD4 T cells. Importantly, these findings are observed using both a lab-adapted and transmitted/founder strain of HIV. We also describe a CD33low cell population, which is transcriptionally similar to LCs but does not appear to function as antigen-presenting cells or acts as HIV target cells. Our findings reveal that epidermal DCs in anogenital tissues potentially play a key role in sexual transmission of HIV. Composition and function of immune populations at barrier surfaces is crucial for response to infection. Here, the authors identify a population of dendritic cells in human epidermis, abundant in anogenital epithelia and distinct from Langerhans cells by surface phenotype and by high capacity for HIV infection and transmission.
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Affiliation(s)
- Kirstie M Bertram
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Rachel A Botting
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia.,Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Heeva Baharlou
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Jake W Rhodes
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Hafsa Rana
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - J Dinny Graham
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Ellis Patrick
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - James Fletcher
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Toby M Plasto
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Naomi R Truong
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Caroline Royle
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Chloe M Doyle
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Orion Tong
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Najla Nasr
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Laith Barnouti
- Australia Plastic Surgery, 185-211, Broadway, Sydney, New South Wales, 2007, Australia
| | - Mark P Kohout
- Australia Plastic Surgery, 185-211, Broadway, Sydney, New South Wales, 2007, Australia
| | - Andrew J Brooks
- Westmead Hospital, Westmead, New South Wales, 2145, Australia
| | - Michael P Wines
- Royal North Shore Hospital, Reserve Rd, St Leonards, New South Wales, 2065, Australia
| | - Peter Haertsch
- Burns Unit, Concord Repatriation General Hospital, Sydney, 2139, New South Wales, Australia
| | - Jake Lim
- Dr Jake Lim PLC, Shop 12, Cnr of Aird & Marsden Street, Parramatta, New South Wales, 2150, Australia
| | - Martijn P Gosselink
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,Westmead Hospital, Westmead, New South Wales, 2145, Australia
| | - Grahame Ctercteko
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,Westmead Hospital, Westmead, New South Wales, 2145, Australia
| | - Jacob D Estes
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Leidos Biomedical Research Inc, Frederick, MD, 21702, USA
| | - Melissa J Churchill
- School of Health and Biomedical Sciences, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria, 3001, Australia
| | - Paul U Cameron
- The Peter Doherty Institute for Infection and Immunity, 792 Elizabeth Street, Melbourne, Victoria, 3000, Australia
| | - Eric Hunter
- Emory Vaccine Center, 954 Gatewood Road, Atlanta, GA, 30329, USA
| | - Muzlifah A Haniffa
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.,Department of Dermatology, Royal Victoria Infirmary, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE2 4LP, UK
| | - Anthony L Cunningham
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia.,The University of Sydney, Sydney, 2006, New South Wales, Australia
| | - Andrew N Harman
- Centre for Virus Research, The Westmead Institute for Medical Research, 176 Hawkesbury Road, Westmead, New South Wales, 2145, Australia. .,The University of Sydney, Sydney, 2006, New South Wales, Australia.
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