1
|
Bertolini M, Gherardini J, Chéret J, Alam M, Sulk M, Botchkareva NV, Biro T, Funk W, Grieshaber F, Paus R. Mechanical epilation exerts complex biological effects on human hair follicles and perifollicular skin: An ex vivo study approach. Int J Cosmet Sci 2024; 46:175-198. [PMID: 37923568 DOI: 10.1111/ics.12923] [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] [Received: 07/06/2023] [Revised: 10/04/2023] [Accepted: 10/12/2023] [Indexed: 11/07/2023]
Abstract
OBJECTIVE Electrical epilation of unwanted hair is a widely used hair removal method, but it is largely unknown how this affects the biology of human hair follicles (HF) and perifollicular skin. Here, we have begun to explore how mechanical epilation changes selected key biological read-out parameters ex vivo within and around the pilosebaceous unit. METHODS Human full-thickness scalp skin samples were epilated ex vivo using an electro-mechanical device, organ-cultured for up to 6 days in serum-free, supplemented medium, and assessed at different time points by quantitative (immuno-)histomorphometry for selected relevant read-out parameters in epilated and sham-epilated control samples. RESULTS Epilation removed most of the hair shafts, often together with fragments of the outer and inner root sheath and hair matrix. This was associated with persistent focal thinning of the HF basal membrane, decreased melanin content of the residual HF epithelium, and increased HF keratinocyte apoptosis, including in the bulge, yet without affecting the number of cytokeratin 15+ HF epithelial stem cells. Sebocyte apoptosis in the peripheral zone was increased, albeit without visibly altering sebum production. Epilation transiently perturbed HF immune privilege, and increased the expression of ICAM-1 in the bulge and bulb mesenchyme, and the number of perifollicular MHC class II+ cells as well as mast cells around the distal epithelium and promoted mast cell degranulation around the suprabulbar and bulbar area. Moreover, compared to controls, several key players of neurogenic skin inflammation, itch, and/or thermosensation (TRPV1, TRPA1, NGF, and NKR1) were differentially expressed in post-epilation skin. CONCLUSION These data generated in denervated, organ-cultured human scalp skin demonstrate that epilation-induced mechanical HF trauma elicits surprisingly complex biological responses. These may contribute to the delayed re-growth of thinner and lighter hair shafts post-epilation and temporary post-epilation discomfort. Our findings also provide pointers regarding the development of topically applicable agents that minimize undesirable sequelae of epilation.
Collapse
Affiliation(s)
- Marta Bertolini
- Monasterium Laboratory Skin and Hair Research Solutions GmbH, Münster, Germany
| | - Jennifer Gherardini
- Monasterium Laboratory Skin and Hair Research Solutions GmbH, Münster, Germany
- Dr Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Jérémy Chéret
- Monasterium Laboratory Skin and Hair Research Solutions GmbH, Münster, Germany
- Dr Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Majid Alam
- Department of Dermatology and Venereology, Qatar Translational Research Institute, Hamad Medical Corporation, Doha, Qatar
| | - Mathias Sulk
- Department of Dermatology, University of Münster, Münster, Germany
| | - Natalia V Botchkareva
- Department of Dermatology, Boston University Chobanian and Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Tamas Biro
- Monasterium Laboratory Skin and Hair Research Solutions GmbH, Münster, Germany
| | - Wolfgang Funk
- Clinic for Plastic, Aesthetic and Reconstructive Surgery, Dr. Dr. med. Funk, Munich, Germany
| | | | - Ralf Paus
- Monasterium Laboratory Skin and Hair Research Solutions GmbH, Münster, Germany
- Dr Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
- CUTANEON - Skin & Hair Innovations, Hamburg, Germany
| |
Collapse
|
2
|
Dahabreh D, Jung S, Renert-Yuval Y, Bar J, Del Duca E, Guttman-Yassky E. Alopecia Areata: Current Treatments and New Directions. Am J Clin Dermatol 2023; 24:895-912. [PMID: 37606849 DOI: 10.1007/s40257-023-00808-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/25/2023] [Indexed: 08/23/2023]
Abstract
Alopecia areata is an autoimmune hair loss disease that is non-scarring and is characterized by chronic inflammation at the hair follicle level. Clinically, patients' presentation varies from patchy, circumscribed scalp involvement to total body and scalp hair loss. Current management is guided by the degree of scalp and body involvement, with topical and intralesional steroid injections as primarily first-line for mild cases and broad immunosuppressants as the mainstay for more severe cases. Until recently, the limited number of blinded, randomized, placebo-controlled clinical trials for this disease had made establishing an evidence-based treatment paradigm challenging. However, growing insights into the pathogenesis of alopecia areata through blood and tissue analysis of human lesions have identified several promising targets for therapy. T-helper (Th) 1/interferon skewing has traditionally been described as the driver of disease; however, recent investigations suggest activation of additional immune mediators, including the Th2 pathway, interleukin (IL)-9, IL-23, and IL-32, as contributors to alopecia areata pathogenesis. The landscape of alopecia areata treatment has the potential to be transformed, as several novel targeted drugs are currently undergoing clinical trials. Given the recent US FDA approval of baricitinib and ritlecitinib, Janus kinase (JAK) inhibitors are a promising drug class for treating severe alopecia areata cases. This article will review the efficacy, safety, and tolerability of current treatments for alopecia areata, and will provide an overview of the emerging therapies that are leading the revolution in the management of this challenging disease.
Collapse
Affiliation(s)
- Dante Dahabreh
- Laboratory of Inflammatory Skin Diseases, Department of Dermatology, Icahn School of Medicine at Mount Sinai, 5 E. 98th Street, New York, NY, 10029, USA
| | - Seungyeon Jung
- Laboratory of Inflammatory Skin Diseases, Department of Dermatology, Icahn School of Medicine at Mount Sinai, 5 E. 98th Street, New York, NY, 10029, USA
- School of Medicine, Vanderbilt University, Nashville, TN, USA
| | - Yael Renert-Yuval
- Laboratory for Investigative Dermatology, The Rockefeller University, New York, NY, USA
| | - Jonathan Bar
- Laboratory of Inflammatory Skin Diseases, Department of Dermatology, Icahn School of Medicine at Mount Sinai, 5 E. 98th Street, New York, NY, 10029, USA
| | - Ester Del Duca
- Laboratory of Inflammatory Skin Diseases, Department of Dermatology, Icahn School of Medicine at Mount Sinai, 5 E. 98th Street, New York, NY, 10029, USA
| | - Emma Guttman-Yassky
- Laboratory of Inflammatory Skin Diseases, Department of Dermatology, Icahn School of Medicine at Mount Sinai, 5 E. 98th Street, New York, NY, 10029, USA.
| |
Collapse
|
3
|
Lee EY, Dai Z, Jaiswal A, Wang EHC, Anandasabapathy N, Christiano AM. Functional interrogation of lymphocyte subsets in alopecia areata using single-cell RNA sequencing. Proc Natl Acad Sci U S A 2023; 120:e2305764120. [PMID: 37428932 PMCID: PMC10629527 DOI: 10.1073/pnas.2305764120] [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: 04/10/2023] [Accepted: 06/05/2023] [Indexed: 07/12/2023] Open
Abstract
Alopecia areata (AA) is among the most prevalent autoimmune diseases, but the development of innovative therapeutic strategies has lagged due to an incomplete understanding of the immunological underpinnings of disease. Here, we performed single-cell RNA sequencing (scRNAseq) of skin-infiltrating immune cells from the graft-induced C3H/HeJ mouse model of AA, coupled with antibody-based depletion to interrogate the functional role of specific cell types in AA in vivo. Since AA is predominantly T cell-mediated, we focused on dissecting lymphocyte function in AA. Both our scRNAseq and functional studies established CD8+ T cells as the primary disease-driving cell type in AA. Only the depletion of CD8+ T cells, but not CD4+ T cells, NK, B, or γδ T cells, was sufficient to prevent and reverse AA. Selective depletion of regulatory T cells (Treg) showed that Treg are protective against AA in C3H/HeJ mice, suggesting that failure of Treg-mediated immunosuppression is not a major disease mechanism in AA. Focused analyses of CD8+ T cells revealed five subsets, whose heterogeneity is defined by an "effectorness gradient" of interrelated transcriptional states that culminate in increased effector function and tissue residency. scRNAseq of human AA skin showed that CD8+ T cells in human AA follow a similar trajectory, underscoring that shared mechanisms drive disease in both murine and human AA. Our study represents a comprehensive, systematic interrogation of lymphocyte heterogeneity in AA and uncovers a novel framework for AA-associated CD8+ T cells with implications for the design of future therapeutics.
Collapse
Affiliation(s)
- Eunice Y. Lee
- Department of Dermatology, Columbia University Irving Medical Center, New York, NY10032
- Medical Scientist Training Program, Columbia University, New York, NY10032
| | - Zhenpeng Dai
- Department of Dermatology, Columbia University Irving Medical Center, New York, NY10032
| | - Abhinav Jaiswal
- Department of Dermatology, Weill Cornell Medicine, New York, NY10021
- Department of Microbiology and Immunology, Weill Cornell Medicine, New York, NY10065
| | - Eddy Hsi Chun Wang
- Department of Dermatology, Columbia University Irving Medical Center, New York, NY10032
| | - Niroshana Anandasabapathy
- Department of Dermatology, Weill Cornell Medicine, New York, NY10021
- Department of Microbiology and Immunology, Weill Cornell Medicine, New York, NY10065
| | - Angela M. Christiano
- Department of Dermatology, Columbia University Irving Medical Center, New York, NY10032
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, NY10032
| |
Collapse
|
4
|
Lee JY, Ju HJ, Han JH, Lee JH, Bae JM, Lee WS, Lee S. Autoimmune, Inflammatory, Atopic, Thyroid, and Psychiatric Outcomes of Offspring Born to Mothers With Alopecia Areata. JAMA Dermatol 2023; 159:711-719. [PMID: 37223925 PMCID: PMC10209830 DOI: 10.1001/jamadermatol.2023.1261] [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: 01/29/2023] [Accepted: 03/30/2023] [Indexed: 05/25/2023]
Abstract
Importance Alopecia areata (AA) is associated with diverse autoimmune and psychiatric disorders. However, an investigation on the long-term outcomes for offspring born to mothers diagnosed with AA is lacking. Objective To investigate the risks for autoimmune, inflammatory, atopic, thyroid, and psychiatric outcomes of offspring born to mothers with AA. Design, Setting, and Participants This retrospective population-based birth cohort study used the linked birth registration database with the Nationwide Health Insurance Service database of Korea. The participants included all newborns born to mothers with 3 or more visits with International Classification of Diseases, Tenth Revision code of L63 and 1:10 birth year, sex, insurance, income, and location of residence-matched control offspring born to mothers without AA during the years from 2003 to 2015. The analysis was conducted from July 2022 to January 2023. Exposure Maternal AA. Main Outcomes and Measures The occurrence of the following diseases was measured in newborns from birth to December 31, 2020: AA, alopecia totalis/universalis (AT/AU), vitiligo, psoriasis, inflammatory bowel disease, rheumatoid arthritis, atopic dermatitis, allergic rhinitis, asthma, hyperthyroidism, hypothyroidism, Graves disease, Hashimoto thyroiditis, attention-deficit hyperactivity disorder, mood disorder, and anxiety disorder. Multivariable Cox proportional hazard analyses were performed with the following covariates: birth year, age, insurance type, income level, location of residence, maternal age, mode of delivery, maternal history of atopic disorders, and autoimmune disorders. Results In total, 67 364 offspring born to 46 352 mothers with AA and 673 640 controls born to 454 085 unaffected mothers were analyzed. The risk of AA (adjusted hazard ratio [aHR], 2.08; 95% CI, 1.88-2.30), AT/AU (aHR, 1.57; 95% CI, 1.18-2.08), vitiligo (aHR, 1.47; 95% CI, 1.32-1.63), atopic disorders (aHR, 1.07; 95% CI, 1.06-1.09), hypothyroidism (aHR, 1.14; 95% CI, 1.03-1.25), and psychiatric disorders (aHR, 1.15; 95% CI, 1.11-1.20) was significantly increased in offspring born to mothers with AA. Among them, 5088 born to mothers with AT/AU were at much greater risk for the development of AT/AU (aHR, 2.98; 95% CI, 1.48-6.00) and psychiatric disorders (aHR, 1.27; 95% CI, 1.12-1.44). Conclusions and Relevance In this Korean retrospective population-based birth cohort study, maternal AA was associated with the development of autoimmune/inflammatory, atopic, thyroid, and psychiatric disorders in their offspring. Clinicians and parents need to be aware of the potential for these comorbidities to occur.
Collapse
Affiliation(s)
- Ju Yeong Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Hyun Jeong Ju
- Department of Dermatology, St Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Ju Hee Han
- Department of Dermatology, Seoul St Mary's Hospital College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Ji Hae Lee
- Department of Dermatology, St Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Jung Min Bae
- Department of Dermatology, St Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
| | - Won-Soo Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Solam Lee
- Department of Dermatology, Yonsei University Wonju College of Medicine, Wonju, Korea
| |
Collapse
|
5
|
Gund R, Christiano AM. Impaired autophagy promotes hair loss in the C3H/HeJ mouse model of alopecia areata. Autophagy 2023; 19:296-305. [PMID: 35652954 PMCID: PMC9809940 DOI: 10.1080/15548627.2022.2074104] [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: 10/24/2021] [Revised: 04/26/2022] [Accepted: 04/29/2022] [Indexed: 01/07/2023] Open
Abstract
Alopecia areata (AA) involves an aberrant immune attack on the hair follicle (HF), which leads to hair loss. Previous genetic data from our lab pointed to a connection between macroautophagy/autophagy and AA pathogenesis, and GWAS identified STX17, CLEC16A and BCL2L11/BIM as risk factors for AA. Additionally, AA patients have copy number deletions in region spanning the ATG4B gene. To test whether autophagy might contribute to disease pathogenesis in AA, we investigated autophagic activity in C3H/HeJ mouse model. We found that autophagy protein SQSTM1 accumulated in HF of AA mice, while in immune cells from AA skin-draining lymph nodes SQSTM1 was not altered, suggesting that autophagic activity is inhibited in the HF of AA mice. Induction of autophagy with Tat-BECN1 peptide attenuated AA, while treatment with the autophagy blocker chloroquine promoted disease, compared to untreated AA mice. Together, our findings suggest the involvement of impaired autophagy in disease pathogenesis of AA.Abbreviations: AA: alopecia areata; CQ: chloroquine; GWAS: genome-wide association studies; HF: hair follicle; MHC: major histocompatibility complex; SDLN: skin-draining lymph nodes.
Collapse
Affiliation(s)
- Rupali Gund
- Department of Dermatology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New YorkUSA
| | - Angela M. Christiano
- Department of Dermatology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New YorkUSA
- Department of Genetics and Development, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
| |
Collapse
|
6
|
Bertolini M, McElwee K, Gilhar A, Bulfone‐Paus S, Paus R. Hair follicle immune privilege and its collapse in alopecia areata. Exp Dermatol 2020; 29:703-725. [DOI: 10.1111/exd.14155] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/18/2020] [Accepted: 07/10/2020] [Indexed: 12/11/2022]
Affiliation(s)
| | - Kevin McElwee
- Monasterium Laboratory Münster Germany
- Centre for Skin Sciences University of Bradford Bradford UK
- Department of Dermatology and Skin Science University of British Columbia Vancouver British Columbia Canada
| | - Amos Gilhar
- Laboratory for Skin Research Rappaport Faculty of Medicine Technion‐Israel Institute of Technology Haifa Israel
| | - Silvia Bulfone‐Paus
- Monasterium Laboratory Münster Germany
- Centre for Dermatology Research University of Manchester and NIHR Manchester Biomedical Research Centre Manchester UK
| | - Ralf Paus
- Monasterium Laboratory Münster Germany
- Centre for Dermatology Research University of Manchester and NIHR Manchester Biomedical Research Centre Manchester UK
- Dr. Philip Frost Department of Dermatology & Cutaneous Surgery University of Miami Miller School of Medicine Miami FL USA
| |
Collapse
|
7
|
Broadley D, McElwee KJ. A "hair-raising" history of alopecia areata. Exp Dermatol 2020; 29:208-222. [PMID: 31960494 DOI: 10.1111/exd.14073] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/19/2019] [Accepted: 01/09/2020] [Indexed: 12/15/2022]
Abstract
A 3500-year-old papyrus from ancient Egypt provides a list of treatments for many diseases including "bite hair loss," most likely alopecia areata (AA). The treatment of AA remained largely unchanged for over 1500 years. In 30 CE, Celsus described AA presenting as scalp alopecia in spots or the "windings of a snake" and suggested treatment with caustic compounds and scarification. The first "modern" description of AA came in 1813, though treatment still largely employed caustic agents. From the mid-19th century onwards, various hypotheses of AA development were put forward including infectious microbes (1843), nerve defects (1858), physical trauma and psychological stress (1881), focal inflammation (1891), diseased teeth (1902), toxins (1912) and endocrine disorders (1913). The 1950s brought new treatment developments with the first use of corticosteroid compounds (1952), and the first suggestion that AA was an autoimmune disease (1958). Research progressively shifted towards identifying hair follicle-specific autoantibodies (1995). The potential role of lymphocytes in AA was made implicit with immunohistological studies (1980s). However, studies confirming their functional role were not published until the development of rodent models (1990s). Genetic studies, particularly genome-wide association studies, have now come to the forefront and open up a new era of AA investigation (2000s). Today, AA research is actively focused on genetics, the microbiome, dietary modulators, the role of atopy, immune cell types in AA pathogenesis, primary antigenic targets, mechanisms by which immune cells influence hair growth, and of course the development of new treatments based on these discoveries.
Collapse
Affiliation(s)
- David Broadley
- Centre for Skin Sciences, University of Bradford, Bradford, UK
| | - Kevin J McElwee
- Centre for Skin Sciences, University of Bradford, Bradford, UK.,Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
8
|
Zhang X, McElwee KJ. Allergy promotes alopecia areata in a subset of patients. Exp Dermatol 2019; 29:239-242. [PMID: 31479542 DOI: 10.1111/exd.14027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 08/02/2019] [Accepted: 08/15/2019] [Indexed: 11/28/2022]
Abstract
In this commentary, we focus on allergy as a facilitating factor in the pathogenesis of alopecia areata (AA). From previous studies on AA, it is well known that subsets of patients can have one or more of; seasonal relapse, comorbid atopic rhinitis, asthma and dermatitis, lesion infiltrating eosinophils and plasma cells, high levels of total IgE, specific IgE for house dust mites (HDMs), and/or disrupted skin barrier function by the evaluation of filaggrin. Allergy and AA share a similar genetic background; both contributing to an immune reaction imbalance. Furthermore, adjunctive treatment with antihistamines, or desensitization for HDM, can reduce the severity of alopecia in atopic AA patients. Therefore, allergies may contribute to the onset and relapse of AA. Identification of an allergic or atopic immune component in AA patient subsets may indicate adjunctive treatment intervention measures against allergies should be taken which may improve the success of conventional AA treatment.
Collapse
Affiliation(s)
- Xingqi Zhang
- Department of Dermatology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Kevin J McElwee
- Centre for Skin Sciences, University of Bradford, Bradford, UK.,Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
9
|
Suh M, Proctor D, Chappell G, Rager J, Thompson C, Borghoff S, Finch L, Ellis-Hutchings R, Wiench K. A review of the genotoxic, mutagenic, and carcinogenic potentials of several lower acrylates. Toxicology 2018; 402-403:50-67. [PMID: 29689363 DOI: 10.1016/j.tox.2018.04.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/28/2018] [Accepted: 04/19/2018] [Indexed: 01/29/2023]
Abstract
Lower alkyl acrylate monomers include methyl-, ethyl-, n-butyl-, and 2-ethylhexyl acrylate. These acrylates are used in the manufacture of acrylic polymers and copolymers for plastics, food packaging, adhesives, and cosmetic formulations. Although there is limited potential for human environmental exposure, occupational exposure can occur via inhalation and dermal contact. Recently, new genotoxicity data have been generated, along with in silico and in vitro read-cross analyses, for these acrylates. The availability of high-throughput screening (HTS) data through the ToxCast™/Tox21 databases allows for consideration of computational toxicology and organization of these data according to the ten key characteristics of carcinogens. Therefore, we conducted a comprehensive review to evaluate the mechanistic, toxicokinetic, animal, and human data, including HTS data, for characterizing the potential carcinogenicity, mutagenicity, and genotoxicity of these acrylates. Toxicokinetic data demonstrate that these acrylates are metabolized rapidly by carboxylesterase hydrolysis and conjugation with glutathione. HTS data demonstrated an overall lack of bioactivity in cancer-related pathways. Overall, the genotoxicity and mutagenicity data support a cytotoxic, non-genotoxic mechanism for these acrylates. Cancer bioassay studies conducted by the oral, dermal, and inhalation routes in animal models with these acrylates did not show any increase in tumor incidence, with two exceptions. At high doses, and secondary to chronic site-of-contact irritation and corrosion, rodent forestomach tumors were induced by oral gavage dosing with ethyl acrylate, and skin tumors were observed following chronic dermal dosing with 2-ethylhexyl acrylate in C3H/HeJ inbred mice (a strain with deficiencies in wound healing), but not in the outbred NMRI strain. For both dermal and forestomach cancers, tumorigenesis is secondary to high doses and long-term tissue damage, shown to be reversible. With evidence that these chemicals are not genotoxic, and that they cause forestomach and dermal tumors through chronic irritation and regenerative proliferation mechanisms, these acrylates are unlikely to pose a human cancer hazard.
Collapse
Affiliation(s)
- Mina Suh
- ToxStrategies, Inc., Mission Viejo, CA 92692, United States
| | | | | | - Julia Rager
- ToxStrategies, Inc., Austin, TX 78759, United States
| | | | | | | | | | | |
Collapse
|
10
|
Abstract
Alopecia areata is an autoimmune disorder characterized by transient, non-scarring hair loss and preservation of the hair follicle. Hair loss can take many forms ranging from loss in well-defined patches to diffuse or total hair loss, which can affect all hair-bearing sites. Patchy alopecia areata affecting the scalp is the most common type. Alopecia areata affects nearly 2% of the general population at some point during their lifetime. Skin biopsies of affected skin show a lymphocytic infiltrate in and around the bulb or the lower part of the hair follicle in the anagen (hair growth) phase. A breakdown of immune privilege of the hair follicle is thought to be an important driver of alopecia areata. Genetic studies in patients and mouse models have shown that alopecia areata is a complex, polygenic disease. Several genetic susceptibility loci were identified to be associated with signalling pathways that are important to hair follicle cycling and development. Alopecia areata is usually diagnosed based on clinical manifestations, but dermoscopy and histopathology can be helpful. Alopecia areata is difficult to manage medically, but recent advances in understanding the molecular mechanisms have revealed new treatments and the possibility of remission in the near future.
Collapse
Affiliation(s)
- C Herbert Pratt
- Department of Genetic Resource Sciences, The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Lloyd E King
- Department of Dermatology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | | | - Angela M Christiano
- Departments of Dermatology and Genetics &Development, Columbia University, New York, New York, USA
| | - John P Sundberg
- Department of Dermatology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Research and Development, The Jackson Laboratory, 600 Main Street, Bar Harbor, Maine 04609-1500, USA
| |
Collapse
|
11
|
Wang EHC, Yu M, Breitkopf T, Akhoundsadegh N, Wang X, Shi FT, Leung G, Dutz JP, Shapiro J, McElwee KJ. Identification of Autoantigen Epitopes in Alopecia Areata. J Invest Dermatol 2016; 136:1617-1626. [PMID: 27094591 DOI: 10.1016/j.jid.2016.04.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 03/21/2016] [Accepted: 04/01/2016] [Indexed: 10/21/2022]
Abstract
Alopecia areata (AA) is believed to be a cell-mediated autoimmune hair loss disease. Both CD4 and cytotoxic CD8 T cells (CTLs) are important for the onset and progression of AA. Hair follicle (HF) keratinocyte and/or melanocyte antigen epitopes are suspected potential targets of autoreactive CTLs, but the specific epitopes have not yet been identified. We investigated the potential for a panel of known epitopes, expressed by HF keratinocytes and melanocytes, to induce activation of CTL populations in peripheral blood mononuclear cells. Specific synthetic epitopes derived from HF antigens trichohyalin and tyrosinase-related protein-2 induced significantly higher frequencies of response in AA CTLs compared with healthy controls (IFN-gamma secretion). Apoptosis assays revealed conditioned media from AA peripheral blood mononuclear cells stimulated with trichohyalin peptides elevated the expression of apoptosis markers in primary HF keratinocytes. A cytokine array revealed higher expression of IL-13 and chemokine ligand 5 (CCL5, RANTES) from AA peripheral blood mononuclear cells stimulated with trichohyalin peptides compared with controls. The data indicate that AA affected subjects present with an increased frequency of CTLs responsive to epitopes originating from keratinocytes and melanocytes; the activated CTLs secreted soluble factors that induced apoptosis in HF keratinocytes. Potentially, CTL response to self-antigen epitopes, particularly trichohyalin epitopes, could be a prognostic marker for human AA.
Collapse
Affiliation(s)
- Eddy H C Wang
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mei Yu
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Trisia Breitkopf
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Noushin Akhoundsadegh
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Xiaojie Wang
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Feng-Tao Shi
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Gigi Leung
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jan P Dutz
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada; Department of Dermatology and Skin Science, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Jerry Shapiro
- Department of Dermatology and Skin Science, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Kevin J McElwee
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, British Columbia, Canada.
| |
Collapse
|
12
|
Gilhar A, Schrum AG, Etzioni A, Waldmann H, Paus R. Alopecia areata: Animal models illuminate autoimmune pathogenesis and novel immunotherapeutic strategies. Autoimmun Rev 2016; 15:726-35. [PMID: 26971464 DOI: 10.1016/j.autrev.2016.03.008] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 03/02/2016] [Indexed: 01/13/2023]
Abstract
One of the most common human autoimmune diseases, alopecia areata (AA), is characterized by sudden, often persisting and psychologically devastating hair loss. Animal models have helped greatly to elucidate critical cellular and molecular immune pathways in AA. The two most prominent ones are inbred C3H/HeJ mice which develop an AA-like hair phenotype spontaneously or after experimental induction, and healthy human scalp skin xenotransplanted onto SCID mice, in which a phenocopy of human AA is induced by injecting IL-2-stimulated PBMCs enriched for CD56+/NKG2D+ cells intradermally. The current review critically examines the pros and cons of the available AA animal models and how they have shaped our understanding of AA pathobiology, and the development of new therapeutic strategies. AA is thought to arise when the hair follicle's (HF) natural immune privilege (IP) collapses, inducing ectopic MHC class I expression in the HF epithelium and autoantigen presentation to autoreactive CD8+ T cells. In common with other autoimmune diseases, upregulation of IFN-γ and IL-15 is critically implicated in AA pathogenesis, as are NKG2D and its ligands, MICA, and ULBP3. The C3H/HeJ mouse model was used to identify key immune cell and molecular principles in murine AA, and proof-of-principle that Janus kinase (JAK) inhibitors are suitable agents for AA management in vivo, since both IFN-γ and IL-15 signal via the JAK pathway. Instead, the humanized mouse model of AA has been used to demonstrate the previously hypothesized key role of CD8+ T cells and NKG2D+ cells in AA pathogenesis and to discover human-specific pharmacologic targets like the potassium channel Kv1.3, and to show that the PDE4 inhibitor, apremilast, inhibits AA development in human skin. As such, AA provides a model disease, in which to contemplate general challenges, opportunities, and limitations one faces when selecting appropriate animal models in preclinical research for human autoimmune diseases.
Collapse
Affiliation(s)
- Amos Gilhar
- Skin Research Laboratory, Faculty of Medicine, Technion - Israel Institute of Technology, Flieman Medical Center, PO Box 9649, Haifa, Israel.
| | - Adam G Schrum
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Amos Etzioni
- Ruth Children Hospital, Haifa, Israel; Rappaport Medical School, Technion, Haifa, Israel
| | - Herman Waldmann
- Therapeutic Immunology Group, Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Ralf Paus
- Centre for Dermatology Research, Inst. of Inflammation and Repair, University of Manchester, Manchester, UK; Department of Dermatology, University of Münster, Münster, Germany
| |
Collapse
|
13
|
Guo H, Cheng Y, Shapiro J, McElwee K. The role of lymphocytes in the development and treatment of alopecia areata. Expert Rev Clin Immunol 2015; 11:1335-51. [PMID: 26548356 DOI: 10.1586/1744666x.2015.1085306] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Alopecia areata (AA) development is associated with both innate and adaptive immune cell activation, migration to peri- and intra-follicular regions, and hair follicle disruption. Both CD4(+) and CD8(+) lymphocytes are abundant in AA lesions; however, CD8(+) cytotoxic T lymphocytes are more likely to enter inside hair follicles, circumstantially suggesting that they have a significant role to play in AA development. Several rodent models recapitulate important features of the human autoimmune disease and demonstrate that CD8(+) cytotoxic T lymphocytes are fundamentally required for AA induction and perpetuation. However, the initiating events, the self-antigens involved, and the molecular signaling pathways, all need further exploration. Studying CD8(+) cytotoxic T lymphocytes and their fate decisions in AA development may reveal new and improved treatment approaches.
Collapse
Affiliation(s)
- Hongwei Guo
- a 1 Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada.,b 2 Department of Dermatology, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China
| | - Yabin Cheng
- a 1 Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada
| | - Jerry Shapiro
- a 1 Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada.,c 3 Department of Dermatology, New York University, Langone Medical Center, New York, USA
| | - Kevin McElwee
- a 1 Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada.,d 4 Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| |
Collapse
|
14
|
Suárez-Fariñas M, Ungar B, Noda S, Shroff A, Mansouri Y, Fuentes-Duculan J, Czernik A, Zheng X, Estrada YD, Xu H, Peng X, Shemer A, Krueger JG, Lebwohl MG, Guttman-Yassky E. Alopecia areata profiling shows TH1, TH2, and IL-23 cytokine activation without parallel TH17/TH22 skewing. J Allergy Clin Immunol 2015; 136:1277-87. [PMID: 26316095 DOI: 10.1016/j.jaci.2015.06.032] [Citation(s) in RCA: 162] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 06/24/2015] [Accepted: 06/25/2015] [Indexed: 01/01/2023]
Abstract
BACKGROUND Alopecia areata (AA) is a common T cell-mediated disorder with limited therapeutics. A molecular profile of cytokine pathways in AA tissues is lacking. Although studies have focused on TH1/IFN-γ responses, several observations support a shared genetic background between AA and atopy. OBJECTIVE We sought to define the AA scalp transcriptome and associated biomarkers with comparisons with atopic dermatitis (AD) and psoriasis. METHODS We performed microarray and RT-PCR profiling of 27 lesional and 17 nonlesional scalp samples from patients with AA for comparison with normal scalp samples (n = 6). AA gene expression was also compared with samples from patients with lesional or nonlesional AD and those with psoriasis. A fold change of greater than 1.5 and a false discovery rate of less than 0.05 were used for differentially expressed genes (DEGs). RESULTS We established the AA transcriptomes (lesional vs nonlesional: 734 DEGs [297 upregulated and 437 downregulated]; lesional vs normal: 4230 DEGs [1980 upregulated and 2250 downregulated]), including many upregulated immune and downregulated hair keratin genes. Equally impressive as upregulation in TH1/interferon markers (IFNG and CXCL10/CXCL9) were those noted in TH2 (IL13, CCL18, CCL26, thymic stromal lymphopoietin, and periostin), TH9/IL-9, IL-23 (p40 and p19), and IL-16 mediators (all P < .05). There were no increases in TH17/TH22 markers. Hair keratin (KRT) expressions (ie, KRT86 and KRT85) were significantly suppressed in lesional skin. Greater scalp involvement (>25%) was associated with greater immune and keratin dysregulation and larger abnormalities in nonlesional scalp samples (ie, CXCL10 and KRT85). CONCLUSIONS Our data associate the AA signature with TH2, TH1, IL-23, and IL-9/TH9 cytokine activation, suggesting consideration of anti-TH2, anti-TH1, and anti-IL-23 targeting strategies. Similar to psoriasis and AD, clinical trials with selective antagonists are required to dissect key pathogenic pathways.
Collapse
Affiliation(s)
- Mayte Suárez-Fariñas
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY; Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY; Department of Genetics and Genomics Science, Icahn School of Medicine at Mount Sinai, New York, NY; Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY; Laboratory for Investigative Dermatology, Rockefeller University, New York, NY
| | - Benjamin Ungar
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY; Laboratory for Investigative Dermatology, Rockefeller University, New York, NY
| | - Shinji Noda
- Laboratory for Investigative Dermatology, Rockefeller University, New York, NY
| | - Anjali Shroff
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Yasaman Mansouri
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY
| | | | - Annette Czernik
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Xiuzhong Zheng
- Laboratory for Investigative Dermatology, Rockefeller University, New York, NY
| | - Yeriel D Estrada
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Hui Xu
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Xiangyu Peng
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Avner Shemer
- Department of Dermatology, Tel-Hashomer, Tel Aviv, Israel
| | - James G Krueger
- Laboratory for Investigative Dermatology, Rockefeller University, New York, NY
| | - Mark G Lebwohl
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Emma Guttman-Yassky
- Department of Dermatology, Icahn School of Medicine at Mount Sinai, New York, NY; Department of Genetics and Genomics Science, Icahn School of Medicine at Mount Sinai, New York, NY; Laboratory for Investigative Dermatology, Rockefeller University, New York, NY; Department of Immunology, Icahn School of Medicine at Mount Sinai, New York, NY.
| |
Collapse
|
15
|
McElwee KJ, Gilhar A, Tobin DJ, Ramot Y, Sundberg JP, Nakamura M, Bertolini M, Inui S, Tokura Y, Jr LEK, Duque-Estrada B, Tosti A, Keren A, Itami S, Shoenfeld Y, Zlotogorski A, Paus R. What causes alopecia areata? Exp Dermatol 2013; 22:609-26. [PMID: 23947678 PMCID: PMC4094373 DOI: 10.1111/exd.12209] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The pathobiology of alopecia areata (AA), one of the most frequent autoimmune diseases and a major unsolved clinical problem, has intrigued dermatologists, hair biologists and immunologists for decades. Simultaneously, both affected patients and the physicians who take care of them are increasingly frustrated that there is still no fully satisfactory treatment. Much of this frustration results from the fact that the pathobiology of AA remains unclear, and no single AA pathogenesis concept can claim to be universally accepted. In fact, some investigators still harbour doubts whether this even is an autoimmune disease, and the relative importance of CD8(+) T cells, CD4(+) T cells and NKGD2(+) NK or NKT cells and the exact role of genetic factors in AA pathogenesis remain bones of contention. Also, is AA one disease, a spectrum of distinct disease entities or only a response pattern of normal hair follicles to immunologically mediated damage? During the past decade, substantial progress has been made in basic AA-related research, in the development of new models for translationally relevant AA research and in the identification of new therapeutic agents and targets for future AA management. This calls for a re-evaluation and public debate of currently prevalent AA pathobiology concepts. The present Controversies feature takes on this challenge, hoping to attract more skin biologists, immunologists and professional autoimmunity experts to this biologically fascinating and clinically important model disease.
Collapse
Affiliation(s)
- K. J. McElwee
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, BC, Canada
| | - A. Gilhar
- Laboratory for Skin, Research, Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, Haifa, Israel Marta Bertolini
| | - D. J. Tobin
- Centre for Skin Sciences, School of Life Sciences, University of Bradford, Bradford, West Yorkshire, BD7 1DP, UK
| | - Y. Ramot
- Department of Dermatology, Hadassah- Hebrew University Medical Center, Jerusalem 91120, Israel
| | - J. P. Sundberg
- The Jackson Laboratory, Bar Harbor, ME, USA; Division of Dermatology, Skin Disease Research Center, Vanderbilt University, Nashville, TN, USA
| | - M. Nakamura
- Department of Dermatology, University of Occupational and Environmental Health, Kitakyushu, Japan Yoshiki Tokura
| | - M. Bertolini
- Department of Dermatology, University of Lübeck, Germany Yehuda Shoenfeld
| | - S. Inui
- Department of Regenerative Dermatology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Y. Tokura
- Department of Dermatology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - L. E. King Jr
- The Jackson Laboratory, Bar Harbor, ME, USA; Division of Dermatology, Skin Disease Research Center, Vanderbilt University, Nashville, TN, USA
| | - B. Duque-Estrada
- Instituto de Dermatologia Prof. Rubem David Azulay, Rio de Janeiro, Brazil Antonella Tosti
| | - A Tosti
- Department of Dermatology, University of Miami, Miami, FL, USA
| | - A. Keren
- Laboratory for Skin, Research, Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, Haifa, Israel Marta Bertolini
| | - S. Itami
- Department of Regenerative Dermatology, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Y. Shoenfeld
- Center for Autoimmune Diseases, Sheba Medical Center, Tel Hashomer and Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel
| | - A. Zlotogorski
- Department of Dermatology, Hadassah- Hebrew University Medical Center, Jerusalem 91120, Israel
| | - R. Paus
- Department of Dermatology, University of Lübeck, Germany; Institute of Inflammation and Repair, University of Manchester, Manchester, UK ,
| |
Collapse
|
16
|
Kibar M, Aktan Ş, Lebe B, Bilgin M. Trichoscopic findings in alopecia areata and their relation to disease activity, severity and clinical subtype in Turkish patients. Australas J Dermatol 2013; 56:e1-6. [PMID: 23991834 DOI: 10.1111/ajd.12102] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Accepted: 06/21/2013] [Indexed: 01/21/2023]
Abstract
BACKGROUND/OBJECTIVE Trichoscopic studies of alopecia areata are helpful in the non-invasive diagnosis and prediction of the course of the disease. The objective was to determine the relationship of trichoscopic findings in alopecia areata with disease activity, severity and clinical subtype in Turkish patients. METHODS Trichoscopic examinations of 39 patients with alopecia areata were compared with 309 alopecia patients including psoriasis (n = 31), seborrhoeic dermatitis (n = 112), female androgenetic alopecia (n = 138), male androgenetic alopecia (n = 63), female androgenetic alopecia of male pattern (n = 5), telogen effluvium (n = 22) and trichotillomania (n = 4). A χ(2) test and logistic regression analysis were used for the statistical analysis. The odds ratios were calculated by cross tabulation. RESULTS There was no relationship between the alopecia areata subtype and trichoscopic findings. On the other hand, a honeycomb hyperpigmentation pattern, cumulus-like clustered white dots, white dots and black dotted pigmentation related to severe disease, while exclamation mark hairs related to mild disease. Exclamation mark hairs were found to be related to active disease while atypical red vessels and white dots were negatively related to disease activity. CONCLUSION In our study, further characteristic trichoscopic findings were detected in alopecia areata such as clustered white dots, multi-hair follicular unit, hidden hairs and black dotted pigmentation, in addition to previous findings. Hence, it is concluded that the identification and prediction of alopecia areata might be straightforward with the help of these new signs such as activation and severity findings.
Collapse
|
17
|
Zhang B, Zhao Y, Cai Z, Caulloo S, McElwee KJ, Li Y, Chen X, Yu M, Yang J, Chen W, Tang X, Zhang X. Early stage alopecia areata is associated with inflammation in the upper dermis and damage to the hair follicle infundibulum. Australas J Dermatol 2013; 54:184-91. [PMID: 23808570 DOI: 10.1111/ajd.12065] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 02/04/2013] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - Sillani Caulloo
- Department of Dermatology; The First Affiliated Hospital, Sun Yat-sen University; China
| | - Kevin J McElwee
- Department of Dermatology and Skin Science; The University of British Columbia; Vancouver; British Columbia; Canada
| | - Yang Li
- Department of Pathology; The First Affiliated Hospital, Sun Yat-sen University; China
| | - Xiaohong Chen
- Department of Dermatology; The First Affiliated Hospital, Sun Yat-sen University; China
| | - Mei Yu
- Department of Dermatology and Skin Science; The University of British Columbia; Vancouver; British Columbia; Canada
| | - Jian Yang
- Department of Dermatology; The First Affiliated Hospital, Sun Yat-sen University; China
| | - Wenna Chen
- Department of Dermatology; The First Affiliated Hospital, Sun Yat-sen University; China
| | - Xuhua Tang
- Department of Dermatology; The First Affiliated Hospital, Sun Yat-sen University; China
| | - Xingqi Zhang
- Department of Dermatology; The First Affiliated Hospital, Sun Yat-sen University; China
| |
Collapse
|
18
|
Alli R, Nguyen P, Boyd K, Sundberg JP, Geiger TL. A mouse model of clonal CD8+ T lymphocyte-mediated alopecia areata progressing to alopecia universalis. THE JOURNAL OF IMMUNOLOGY 2011; 188:477-86. [PMID: 22116824 DOI: 10.4049/jimmunol.1100657] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Alopecia areata is among the most prevalent autoimmune diseases, yet compared with other autoimmune conditions, it is not well studied. This in part results from limitations in the C3H/HeJ mouse and DEBR rat model systems most commonly used to study the disease, which display a low frequency and late onset. We describe a novel high-incidence model for spontaneous alopecia areata. The 1MOG244 T cell expresses dual TCRA chains, one of which, when combined with the single TCRB present, promotes the development of CD8(+) T cells with specificity for hair follicles. Retroviral transgenic mice expressing this TCR develop spontaneous alopecia areata at nearly 100% incidence. Disease initially follows a reticular pattern, with regionally cyclic episodes of hair loss and regrowth, and ultimately progresses to alopecia universalis. Alopecia development is associated with CD8(+) T cell activation, migration into the intrafollicular region, and hair follicle destruction. The disease may be adoptively transferred with T lymphocytes and is class I and not class II MHC-dependent. Pathologic T cells primarily express IFNG and IL-17 early in disease, with dramatic increases in cytokine production and recruitment of IL-4 and IL-10 production with disease progression. Inhibition of individual cytokines did not significantly alter disease incidence, potentially indicating redundancy in cytokine responses. These results therefore characterize a new high-incidence model for alopecia areata in C57BL/6J mice, the first to our knowledge to apply a monoclonal TCR, and indicate that class I MHC-restricted CD8(+) T lymphocytes can independently mediate the pathologic response.
Collapse
Affiliation(s)
- Rajshekhar Alli
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | | | | | | | | |
Collapse
|
19
|
Abstract
Alopecia areata (AA) is a nonscarring, inflammatory skin disease that results in patchy hair loss. AA is unpredictable in its onset, severity, and duration making it potentially very stressful for affected individuals. Currently, the treatment options for AA are limited and the efficacy of these treatments varies from patient to patient. The exact etiology of AA is unknown. This article provides some insights into the etiopathogenesis of AA and why some people develop it. The current knowledge on the pathogenesis of AA is summarized and some of the recent hypotheses and studies on AA are presented to allow for a fuller understanding of the possible biological mechanisms of AA.
Collapse
Affiliation(s)
- Eddy Wang
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada
| | | |
Collapse
|
20
|
Alopecia areata update: part I. Clinical picture, histopathology, and pathogenesis. J Am Acad Dermatol 2010; 62:177-88, quiz 189-90. [PMID: 20115945 DOI: 10.1016/j.jaad.2009.10.032] [Citation(s) in RCA: 284] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 09/08/2009] [Accepted: 10/12/2009] [Indexed: 12/15/2022]
Abstract
UNLABELLED Alopecia areata (AA) is an autoimmune disease that presents as nonscarring hair loss, although the exact pathogenesis of the disease remains to be clarified. Disease prevalence rates from 0.1% to 0.2% have been estimated for the United States. AA can affect any hair-bearing area. It often presents as well demarcated patches of nonscarring alopecia on skin of overtly normal appearance. Recently, newer clinical variants have been described. The presence of AA is associated with a higher frequency of other autoimmune diseases. Controversially, there may also be increased psychiatric morbidity in patients with AA. Although some AA features are known poor prognostic signs, the course of the disease is unpredictable and the response to treatment can be variable. Part one of this two-part series on AA describes the clinical presentation and the associated histopathologic picture. It also proposes a hypothesis for AA development based on the most recent knowledge of disease pathogenesis. LEARNING OBJECTIVES After completing this learning activity, participants should be familiar with the most recent advances in AA pathogenesis, recognize the rare and recently described variants of AA, and be able to distinguish between different histopathologic stages of AA.
Collapse
|
21
|
Marhaba R, Vitacolonna M, Hildebrand D, Baniyash M, Freyschmidt-Paul P, Zöller M. The importance of myeloid-derived suppressor cells in the regulation of autoimmune effector cells by a chronic contact eczema. THE JOURNAL OF IMMUNOLOGY 2007; 179:5071-81. [PMID: 17911592 DOI: 10.4049/jimmunol.179.8.5071] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Induction of a chronic eczema is a most efficient therapy for alopecia areata (AA). We had noted a reduction in regulatory T cells during AA induction and wondered whether regulatory T cells may become recruited or expanded during repeated skin sensitization or whether additional regulatory cells account for hair regrowth. AA could not be cured by the transfer of CD4(+)CD25(high) lymph node cells from mice repeatedly treated with a contact sensitizer. This obviously is a consequence of a dominance of freshly activated cells as compared with regulatory CD4(+)CD25(+) T cells. Instead, a population of Gr-1(+)CD11b(+) cells was significantly increased in skin and spleen of AA mice repeatedly treated with a contact sensitizer. Gr-1(+)CD11b(+) spleen cells mostly expressed CD31. Expression of several proinflammatory cytokines as well as of the IFN-gamma receptor and the TNF receptor I were increased. Particularly in the skin, Gr-1(+) cells expressed several chemokines and CCR8 at high levels. Gr-1(+)CD11b(+) cells most potently suppressed AA effector cell proliferation in vitro and promoted partial hair regrowth in vivo. When cocultured with CD4(+) or CD8(+) cells from AA mice, the Gr-1(+)CD11b(+) cells secreted high levels of NO. However, possibly due to high level Bcl-2 protein expression in AA T cells, apoptosis induction remained unaltered. Instead, zeta-chain expression was strongly down-regulated, which was accompanied by a decrease in ZAP70 and ERK1/2 phosphorylation. Thus, a chronic eczema supports the expansion and activation of myeloid suppressor cells that, via zeta-chain down-regulation, contribute to autoreactive T cell silencing in vitro and in vivo.
Collapse
MESH Headings
- Allergens/administration & dosage
- Allergens/immunology
- Alopecia Areata/immunology
- Alopecia Areata/pathology
- Animals
- Autoimmune Diseases/immunology
- Autoimmune Diseases/pathology
- Autoimmune Diseases/therapy
- Chronic Disease
- Cyclobutanes/administration & dosage
- Cyclobutanes/immunology
- Dermatitis, Contact/immunology
- Dermatitis, Contact/pathology
- Dermatitis, Contact/therapy
- Down-Regulation/immunology
- Hypersensitivity, Delayed/immunology
- Hypersensitivity, Delayed/pathology
- Membrane Proteins/antagonists & inhibitors
- Membrane Proteins/biosynthesis
- Mice
- Mice, Inbred C3H
- Myeloid Cells/cytology
- Myeloid Cells/immunology
- Receptors, Antigen, T-Cell/antagonists & inhibitors
- Receptors, Antigen, T-Cell/biosynthesis
- T-Lymphocytes, Regulatory/cytology
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
Collapse
Affiliation(s)
- Rachid Marhaba
- Department of Tumor Progression and Immune Defense, German Cancer Research Center, Heidelberg, Germany
| | | | | | | | | | | |
Collapse
|
22
|
Ross EK, Vincenzi C, Tosti A. Videodermoscopy in the evaluation of hair and scalp disorders. J Am Acad Dermatol 2006; 55:799-806. [PMID: 17052485 DOI: 10.1016/j.jaad.2006.04.058] [Citation(s) in RCA: 253] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2006] [Revised: 04/12/2006] [Accepted: 04/16/2006] [Indexed: 12/17/2022]
Abstract
BACKGROUND The standard methods used to diagnose scalp and hair disorders (eg, simple clinical inspection, pull test, biopsy) vary in sensitivity, reproducibility, and invasiveness. Studies on a few entities suggest that use of dermoscopy can improve clinical accuracy, but further investigation is needed. OBJECTIVES We sought to: (1) characterize features of several nontumoral scalp and hair conditions using videodermoscopy; and (2) assess the potential usefulness of videodermoscopy in the clinical evaluation of these conditions. METHODS Images (x20-70 magnification) obtained with videodermoscopy from 220 patients with various scalp and hair disorders and 15 unaffected control subjects were reviewed for distinguishing features. RESULTS Conditions evaluated included psoriasis (23), seborrheic dermatitis (26), alopecia areata (58), androgenetic alopecia (64), chronic telogen effluvium (7), trichotillomania (12), and primary cicatricial alopecia (30). Clinical features evident to the naked eye were seen in great detail when videodermoscopy was used. Novel features (eg, yellow dots in alopecia areata) were also identified. LIMITATIONS Findings require confirmation by blinded, prospective investigation. CONCLUSIONS Use of videodermoscopy in the clinical evaluation of scalp and hair disorders improves diagnostic capability beyond simple clinical inspection and reveals novel features of disease, which may extend clinical and pathogenetic understanding.
Collapse
|
23
|
Abstract
Hair follicles, or pilosebacous units, are complicated anatomic structures. Analysis of abnormalities of these structures can be difficult without adequate knowledge of normal changes associated with embryonic and postnatal development as well as regular cycling. A variety of systematic approaches to analysis of the pilosebacous unit are provided here.
Collapse
|
24
|
Okada M, Tashiro-Yamaji J, Takahashi T, Nomi H, Yamamoto Y, Yamaguchi S, Ueda K, Kubota T, Yoshida R. Regulation of Hair Regrowth in Alopecic Site of IFN-γ−/−Mice by Macrophages Infiltrating into Allograft in IFN-γ+/+Mice. J Interferon Cytokine Res 2005; 25:564-74. [PMID: 16181057 DOI: 10.1089/jir.2005.25.564] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We previously demonstrated that around 6 weeks of age, most of the interferon-gamma (IFN-gamma)-/- C57BL/6 mice began to lose morphogenesis-derived hairs in their dorsal and occipital areas and that hair regrowth in the alopecic site was induced by intraperitoneal (i.p.) injection of IFN-gamma and allogeneic Meth A cells. Here, we explored the IFN-gamma mRNA expression in the cells infiltrating into allograft in IFN-gamma(+)/(+) mice by RT-PCR and adoptively transferred specific antigen-minus infiltrates into IFN-gamma-/- mice to assess the hair regrowth inducibility. IFN- gamma mRNA was expressed in the infiltrates on days 3-8 after allografting, with a peak on day 3 or 4, and CD4(+) and F4/80(+) cells were the major producers of IFN-gamma. All infiltrates on day 3 induced hair regrowth, whereas those on days 0-2 or 4-8 were ineffective or partially effective, respectively. The removal of F4/80(+) macrophages from all infiltrates failed to induce hair regrowth, whereas the removal of Ly-6C(+) macrophages rather accelerated the hair regrowth. These results showed that F4/80(+), Ly-6C(+), and CD4(+) and F4/80(+) cells were stimulatory, inhibitory, and IFN-gamma-producing cells, respectively, in the regulation of hair regrowth.
Collapse
Affiliation(s)
- Masashi Okada
- Department of Physiology, Osaka Medical College, Takatsuki, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
25
|
McElwee KJ, Yu M, Park SW, Ross EK, Finner A, Shapiro J. What Can We Learn from Animal Models of Alopecia areata? Dermatology 2005; 211:47-53. [PMID: 15983437 DOI: 10.1159/000085580] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Alopecia areata (AA) is a hair loss disease marked by a focal inflammatory infiltrate of dystrophic anagen stage hair follicles by CD4+ and CD8+ lymphocytes. Although AA is thought to be an autoimmune disorder, definitive proof is lacking. Moreover, characterization of the primary pathogenic mechanisms by which hair loss is induced in AA is limited. In this context, animal models may provide a vital contribution to understanding AA. Recent research using animal models of AA has focused on providing evidence in support of a lymphocyte-mediated pathogenic mechanism consistent with AA as an autoimmune disease. In the future, research with both humans and animal models shall likely concentrate on identifying the primary antigenic epitopes involved in AA and the genetics of AA susceptibility. With a comprehensive understanding of the key elements in AA pathogenesis, new avenues for therapeutic research and intervention will be defined.
Collapse
Affiliation(s)
- Kevin J McElwee
- Division of Dermatology, University of British Columbia, Vancouver, Canada.
| | | | | | | | | | | |
Collapse
|
26
|
Gilhar A, Kam Y, Assy B, Kalish RS. Alopecia areata induced in C3H/HeJ mice by interferon-gamma: evidence for loss of immune privilege. J Invest Dermatol 2005; 124:288-9. [PMID: 15654992 DOI: 10.1111/j.0022-202x.2004.23580.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
27
|
Zöller M, Freyschmidt-Paul P, Vitacolonna M, McElwee KJ, Hummel S, Hoffmann R. Chronic delayed-type hypersensitivity reaction as a means to treat alopecia areata. Clin Exp Immunol 2004; 135:398-408. [PMID: 15008971 PMCID: PMC1808967 DOI: 10.1111/j.1365-2249.2003.02380.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The acute phase of alopecia areata (AA) is characterized by an increase in CD44v3+ and CD44v10+ skin-infiltrating leucocytes (SkIL). Induction of a contact eczema, one of the therapeutic options in AA, can be mitigated strongly by a blockade of CD44v10. The observation that induction of a delayed type hypersensitivity (DTH) reaction abrogates an autoimmune reaction, where both responses apparently use similar effector mechanisms, is surprising and prompted us to search for the underlying mechanisms. AA-affected C3H/HeJ mice were treated with the contact sensitizer SADBE (squaric acid dibutylester) and leucocyte subpopulations and their activation state was evaluated in SkIL and draining lymph nodes. AA-affected mice exhibited an increased number of SkIL with a predominance of T lymphocytes. After treatment with the contact sensitizer SADBE recovery of SkIL was reduced and monocytes predominated. However, a significantly increased number of leucocytes was recovered from draining lymph nodes. Draining lymph node cells from untreated and treated AA mice exhibited all signs of recent activation with high-level expression of co-stimulatory and accessory molecules and an increased percentage of CD44v3+ and CD44v10+ leucocytes. In contrast, SkIL of SADBE-treated AA mice contained relatively few activated T cells and reduced numbers of CD44v3+ and CD44v10+ cells. Thus, the activation state and the distribution of leucocyte subsets in SADBE-treated AA mice are consistent with a blockade of leucocyte extravasation. Accordingly, the therapeutic effect of long-term SADBE treatment may rely on impaired leucocyte traffic.
Collapse
Affiliation(s)
- M Zöller
- Department of Tumor Progression and Tumor Defense, German Cancer Research Center, Heidelberg, Germany.
| | | | | | | | | | | |
Collapse
|
28
|
Abstract
T cells play an important role in alopecia areata (AA) because AA can be reinduced by the injection of hair follicle-specific CD8+ T cells into AA scalp biopsies, which were grafted onto scid mice, and the depletion of CD8+ T cells restores hair growth in the Dundee experimental bald rat. Moreover, AA can be transferred by grafting of alopecic skin from C3H/HeJ mice with AA-like hair loss onto unaffected littermates, but the onset of AA is inhibited by i.p. injection of anti-CD44v10 antibodies. Interestingly, grafted anti-CD44v10-treated mice have decreased numbers of CD8+ T cells within the skin. Beside T cells several clinical and experimental data point towards cytokines that might be crucial inducers of hair loss in AA. An aberrant expression of cytokines of the Thl type and IL-1beta has been detected in scalp areas involved by AA, and polymorphisms of cytokine genes such as IL-1-receptor antagonist, IL-1alpha, and TNF-alpha have been shown to determine disease susceptibility and severity. Moreover, IL-1 has been shown to be a potent inhibitor of human hair growth in vitro. Such IL-1-incubated hair follicles show ultrastructural changes similar to those observable in vivo. On the other hand mice transgenic for IL-1alpha develop patchy hair loss and during the depilation-induced hair cycle in C57/BL6 mice, members of the IL-1 family are overexpressed with the onset of spontaneous catagen. Taking all of the presently available data together, we may hypothesize that CD8+ T cells are of crucial importance in AA by their interaction with MHC-I restricted autoantigens, and cytolysis of their target cells. Hair loss, however, may occur because proinflammatory cytokines may interfere with the hair cycle leading to premature arrest of hair cycling.
Collapse
Affiliation(s)
- R Hoffmann
- Department of Dermatology, Philipp University, Marburg, Germany.
| |
Collapse
|