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Ortner D, Strandt H, Tripp CH, Spoeck S, Seretis A, Hornsteiner F, Dieckmann S, Schmuth M, Stoitzner P. Langerhans cells orchestrate apoptosis of DNA-damaged keratinocytes upon high-dose UVB skin exposure. Eur J Immunol 2024:e2451020. [PMID: 39288297 DOI: 10.1002/eji.202451020] [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: 01/19/2024] [Revised: 08/27/2024] [Accepted: 08/30/2024] [Indexed: 09/19/2024]
Abstract
Ultraviolet (UV) irradiation of the skin causes mutations that can promote the development of melanoma and nonmelanoma skin cancer. High-dose UVB exposure triggers a vigorous skin reaction characterized by inflammation resulting in acute sunburn. This response includes the formation of sunburn cells and keratinocytes (KC) undergoing programmed cell death (apoptosis) when repair mechanisms of DNA damage are inadequate. The primary objective of this research was to clarify the involvement of Langerhans cells (LC) in the development of acute sunburn following intense UVB skin irradiation. To address this, we subjected the dorsal skin of mice to a single high-dose UVB exposure and analyzed the immediate immune response occurring within the skin tissue. Acute sunburn triggered an activation of LC, coinciding with a rapid influx of neutrophils that produced TNF-α. Furthermore, our investigation unveiled a marked increase in DNA-damaged KC and the subsequent induction of apoptosis in these cells. Importantly, we demonstrate a crucial link between the inflammatory cascade, the initiation of apoptosis in DNA-damaged KC, and the presence of LC in the skin. LC were observed to modulate the chemokine response in the skin following exposure to UVB, thereby affecting the trafficking of neutrophils. Skin lacking LC revealed diminished inflammation, contained fewer TNF-α-producing neutrophils, and due to the prevention of apoptosis induction, a lingering population of DNA-damaged KC, presumably carrying the risk of enduring genomic alterations. In summary, our results underscore the pivotal role of LC in preserving the homeostasis of UVB-irradiated skin. These findings contribute to a deeper understanding of the intricate mechanisms underlying acute sunburn responses and their implications for UV-induced skin cancer.
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Affiliation(s)
- Daniela Ortner
- Department of Dermatology, Venereology & Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Helen Strandt
- Department of Dermatology, Venereology & Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Christoph H Tripp
- Department of Dermatology, Venereology & Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Sarah Spoeck
- Division of Developmental Immunology, Medical University of Innsbruck, Innsbruck, Austria
| | - Athanasios Seretis
- Research Institute for Biomedical Ageing Research, University of Innsbruck, Innsbruck, Austria
| | - Florian Hornsteiner
- Department of Dermatology, Venereology & Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Sophie Dieckmann
- Department of Dermatology, Venereology & Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Matthias Schmuth
- Department of Dermatology, Venereology & Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Patrizia Stoitzner
- Department of Dermatology, Venereology & Allergology, Medical University of Innsbruck, Innsbruck, Austria
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2
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Nasr Z, Virupakshaiah A, Schoeps VA, Cherbuin N, Casper TC, Waltz M, Hart J, Rodriguez M, Gorman MP, Benson LA, Chitnis T, Rensel M, Abrams A, Krupp L, Waldman AT, Lotze T, Aaen GS, Mar S, Schreiner T, Wheeler Y, Rose J, Shukla NM, Barcellos LF, Lucas R, Waubant E. Gene-environment interactions and risk of pediatric-onset multiple sclerosis associated with time spent outdoors. Mult Scler Relat Disord 2024; 82:105351. [PMID: 38141560 DOI: 10.1016/j.msard.2023.105351] [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: 07/20/2023] [Revised: 11/12/2023] [Accepted: 12/03/2023] [Indexed: 12/25/2023]
Abstract
BACKGROUND Our previous study identified a significant association between lower time spent outdoors, as a proxy of sun exposure, and a higher risk of pediatric-onset multiple sclerosis (POMS). UV radiation modulates the expression of several genes, but it is unknown whether these genes modify the effect of sun exposure on POMS risk. METHODS In an age- and sex-matched case-control study, we evaluated the additive and multiplicative interactions between time spent outdoors and genetic non-HLA risk variants for developing POMS within the metabolic pathways of UV radiation, including CD28(rs6435203), CD86(rs9282641), and NFkB1(rs7665090) and the top two HLA risk factors (presence of DRB1×15 and absence of A*02). RESULTS In an adjusted model (332 POMS cases, 534 healthy controls), greater time compared to <30 min/day spent outdoors during the prior summer and higher UV radiation dose were associated with decreased odds of POMS (OR 0.66, 95% CI 0.56-0.78, p < 0.001; OR 0.78, 95 % CI 0.62-0.98, p = 0.04, respectively). No significant additive or multiplicative interactions were found between risk factors. CONCLUSIONS The exploration of gene-environment interactions in the risk of developing MS can unravel the underlying mechanisms involved. Although we do not have evidence that our candidate genes contribute to interactions, other genes may.
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Affiliation(s)
- Zahra Nasr
- UCSF Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA.
| | - Akash Virupakshaiah
- UCSF Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Vinicius Andreoli Schoeps
- UCSF Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | - Nicolas Cherbuin
- Centre for Research on Ageing, Health and Wellbeing, Australian National University, Canberra, Australia
| | - T Charles Casper
- University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Michael Waltz
- University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Janace Hart
- UCSF Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
| | | | - Mark P Gorman
- Boston Childrens Hospital, Boston, Massachusetts, USA
| | | | - Tanuja Chitnis
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | | | | - Lauren Krupp
- New York University Medical Center, New York City, New York, USA
| | - Amy T Waldman
- Division of Child Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Tim Lotze
- Texas Children's Hospital, Houston, Texas, USA
| | - Gregory S Aaen
- Loma Linda University Children's Hospital, Loma Linda, California, USA
| | - Soe Mar
- Washington University in St. Louis, St Louis, Missouri, USA
| | - Teri Schreiner
- Childrens Hospital Colorado/University of Colorado, Aurora, Colorado, USA
| | | | - John Rose
- George E. Wahlen Department of Veterans Affairs Medical Center, University of Utah, Salt Lake City, UT, USA
| | - Nikita Melani Shukla
- Baylor College of Medicine/Texas Children's Hospital, Neurology and Developmental Neuroscience, Houston, Texas, USA
| | - Lisa F Barcellos
- Genetic Epidemiology and Genomics Laboratory, Divisions of Epidemiology and Biostatistics, School of Public Health, University of California Berkeley, Berkeley, California, USA
| | - Robyn Lucas
- National Centre for Epidemiology and Population Health, Australian National University, Canberra, Australia
| | - Emmanuelle Waubant
- UCSF Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA, USA
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3
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Zhao J, Zhang X, Zhang D, Tang Q, Bi Y, Yuan L, Yang B, Li X, Li Z, Deng D, Cao W. Critical genes in human photoaged skin identified using weighted gene co-expression network analysis. Genomics 2023; 115:110682. [PMID: 37454939 DOI: 10.1016/j.ygeno.2023.110682] [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: 01/30/2023] [Revised: 05/24/2023] [Accepted: 07/12/2023] [Indexed: 07/18/2023]
Abstract
Photoaging is unique to the skin and is accompanied by an increased risk of tumors. To explore the transcriptomic regulatory mechanism of skin photoaging, the epidermis, and dermis of 16 healthy donors (eight exposed and eight non-exposed) were surgically excised and detected using total RNA-Seq. Weighted gene co-expression network analysis (WGCNA) identified the most relevant modules with exposure. The hub genes were identified using correlation, p-value, and enrichment analysis. The critical genes were identified using Support Vector Machine-Recursive Feature Elimination (SVM-RFE) and least absolute shrinkage and selection operator (LASSO) regression, then enriched using single-gene GSEA. A competitive endogenous RNA (ceRNA) network was constructed and validated using qRT-PCR. Compared with non-exposed sites, 430 mRNAs, 168 lncRNAs, and 136 miRNAs were differentially expressed in the exposed skin. WGCNA identified the module MEthistle and 12 intersecting genes from the 71 genes in this module. The enriched pathways were related to muscle. The critical genes were KLHL41, MYBPC2, and ERAP2. Single-gene GSEA identified the Hippo signaling pathway, basal cell carcinoma, cell adhesion molecules, and other pathways. Six miRNAs and 18 lncRNAs related to the critical genes constituted the ceRNA network and were verified using qPCR. The differential expression of KLHL41, MYBPC2, and ERAP2 at the protein level was verified using immunohistochemistry. KLHL41, MYBPC2, and ERAP2 genes are related to skin photoaging. The prediction model based on the three critical genes can indicate photoaging. These critical genes may have a role in skin photoaging by regulating cell growth, intercellular adhesion, and substance metabolism pathways.
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Affiliation(s)
- Jie Zhao
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Xun Zhang
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Dafu Zhang
- Department of Radiology, Yunnan Cancer Hospital, Kunming, Yunnan, China
| | - Qiao Tang
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China; Department of dermatology, Qionglai City Medical Center Hospital, Qionglai, Sichuan, China
| | - Yunfeng Bi
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Limei Yuan
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Binbin Yang
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Xiaolan Li
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Zhenhui Li
- Department of Radiology, Yunnan Cancer Hospital, Kunming, Yunnan, China.
| | - Danqi Deng
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China.
| | - Wenting Cao
- Department of dermatology, The Second Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China.
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4
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Tse BCY, Ferguson AL, Koay YC, Grau GE, Don AS, Byrne SN. Exposure to solar ultraviolet radiation establishes a novel immune suppressive lipidome in skin-draining lymph nodes. Front Immunol 2023; 13:1045731. [PMID: 36741361 PMCID: PMC9895826 DOI: 10.3389/fimmu.2022.1045731] [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: 09/16/2022] [Accepted: 12/22/2022] [Indexed: 01/21/2023] Open
Abstract
The ability of ultraviolet radiation to suppress the immune system is thought to be central to both its beneficial (protection from autoimmunity) and detrimental (carcinogenic) effects. Previous work revealed a key role for lipids particularly platelet-activating factor and sphingosine-1-phosphate in mediating UV-induced immune suppression. We therefore hypothesized that there may be other UV-induced lipids that have immune regulatory roles. To assess this, mice were exposed to an immune suppressive dose of solar-simulated UV (8 J/cm2). Lipidomic analysis identified 6 lipids (2 acylcarnitines, 2 neutral lipids, and 2 phospholipids) with significantly increased levels in the skin-draining lymph nodes of UV-irradiated mice. Imaging mass spectrometry of the lipids in combination with imaging mass cytometry identification of lymph node cell subsets indicated a preferential location of UV-induced lipids to T cell areas. In vitro co-culture of skin-draining lymph node lipids with lymphocytes showed that lipids derived from UV-exposed mice have no effect on T cell activation but significantly inhibited T cell proliferation, indicating that the lipids play an immune regulatory role. These studies are important first steps in identifying novel lipids that contribute to UV-mediated immune suppression.
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Affiliation(s)
- Benita C. Y. Tse
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Angela L. Ferguson
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Yen Chin Koay
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, NSW, Australia,Heart Research Institute, The University of Sydney, Sydney, NSW, Australia
| | - Georges E. Grau
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Anthony S. Don
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Scott N. Byrne
- The University of Sydney, School of Medical Sciences, Faculty of Medicine and Health, Sydney, NSW, Australia,Westmead Institute for Medical Research, Centre for Immunology and Allergy Research, Sydney, NSW, Australia,*Correspondence: Scott N. Byrne,
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5
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Marsh‐Wakefield F, Juillard P, Ashhurst TM, Juillard A, Shinko D, Putri GH, Read MN, McGuire HM, Byrne SN, Hawke S, Grau GE. Peripheral B-cell dysregulation is associated with relapse after long-term quiescence in patients with multiple sclerosis. Immunol Cell Biol 2022; 100:453-467. [PMID: 35416319 PMCID: PMC9322415 DOI: 10.1111/imcb.12552] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/07/2022] [Accepted: 04/11/2022] [Indexed: 12/17/2022]
Abstract
B cells play a major role in multiple sclerosis (MS), with many successful therapeutics capable of removing them from circulation. One such therapy, alemtuzumab, is thought to reset the immune system without the need for ongoing therapy in a proportion of patients. The exact cells contributing to disease pathogenesis and quiescence remain to be identified. We utilized mass cytometry to analyze B cells from the blood of patients with relapse-remitting MS (RRMS) before and after alemtuzumab treatment, and during relapse. A complementary RRMS cohort was analyzed by single-cell RNA sequencing. The R package "Spectre" was used to analyze these data, incorporating FlowSOM clustering, sparse partial least squares-discriminant analysis and permutational multivariate analysis of variance. Immunoglobulin (Ig)A+ and IgG1 + B-cell numbers were altered, including higher IgG1 + B cells during relapse. B-cell linker protein (BLNK), CD40 and CD210 expression by B cells was lower in patients with RRMS compared with non-MS controls, with similar results at the transcriptomic level. Finally, alemtuzumab restored BLNK, CD40 and CD210 expression by IgA+ and IgG1 + B cells, which was altered again during relapse. These data suggest that impairment of IgA+ and IgG1 + B cells may contribute to MS pathogenesis, which can be restored by alemtuzumab.
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Affiliation(s)
- Felix Marsh‐Wakefield
- Vascular Immunology Unit, School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Liver Injury and Cancer ProgramCentenary InstituteSydneyNSWAustralia
- Human Cancer and Viral Immunology LaboratoryThe University of SydneySydneyNSWAustralia
| | - Pierre Juillard
- Vascular Immunology Unit, School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
| | - Thomas M Ashhurst
- Sydney Cytometry Core Research FacilityThe University of SydneySydneyNSWAustralia
- School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
| | - Annette Juillard
- Vascular Immunology Unit, School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
| | - Diana Shinko
- Sydney Cytometry Core Research FacilityThe University of SydneySydneyNSWAustralia
- Ramaciotti Facility for Human Systems BiologyThe University of SydneySydneyNSWAustralia
| | - Givanna H Putri
- School of Computer ScienceThe University of SydneySydneyNSWAustralia
| | - Mark N Read
- School of Computer ScienceThe University of SydneySydneyNSWAustralia
| | - Helen M McGuire
- Ramaciotti Facility for Human Systems BiologyThe University of SydneySydneyNSWAustralia
- Translational Immunology Group, School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
| | - Scott N Byrne
- School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Centre for Immunology and Allergy ResearchThe Westmead Institute for Medical ResearchWestmeadNSWAustralia
| | - Simon Hawke
- Vascular Immunology Unit, School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Central West Neurology and NeurosurgeryOrangeNSWAustralia
| | - Georges E Grau
- Vascular Immunology Unit, School of Medical Sciences, Faculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
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Tse BCY, Ireland RA, Lee JY, Marsh-Wakefield F, Kok LF, Don AS, Byrne SN. Exposure to Systemic Immunosuppressive Ultraviolet Radiation Alters T Cell Recirculation through Sphingosine-1-Phosphate. THE JOURNAL OF IMMUNOLOGY 2021; 207:2278-2287. [PMID: 34561229 DOI: 10.4049/jimmunol.2001261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 08/25/2021] [Indexed: 11/19/2022]
Abstract
Systemic suppression of adaptive immune responses is a major way in which UV radiation contributes to skin cancer development. Immune suppression is also likely to explain how UV protects from some autoimmune diseases, such as multiple sclerosis. However, the mechanisms underlying UV-mediated systemic immune suppression are not well understood. Exposure of C57BL/6 mice to doses of UV known to suppress systemic autoimmunity led to the accumulation of cells within the skin-draining lymph nodes and away from non-skin-draining lymph nodes. Transfer of CD45.1+ cells from nonirradiated donors into CD45.2+ UV-irradiated recipients resulted in preferential accumulation of donor naive T cells and a decrease in activated T cells within skin-draining lymph nodes. A single dose of immune-suppressive UV was all that was required to cause a redistribution of naive and central memory T cells from peripheral blood to the skin-draining lymph nodes. Specifically, CD69-independent increases in sphingosine-1-phosphate (S1P) receptor 1-negative naive and central memory T cells occurred in these lymph nodes. Mass spectrometry analysis showed UV-mediated activation of sphingosine kinase 1 activity, resulting in an increase in S1P levels within the lymph nodes. Topical application of a sphingosine kinase inhibitor on the skin prior to UV irradiation eliminated the UV-induced increase in lymph node S1P and T cell numbers. Thus, exposure to immunosuppressive UV disrupts T cell recirculation by manipulating the S1P pathway.
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Affiliation(s)
- Benita C Y Tse
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Rachael A Ireland
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Westmead Institute for Medical Research, Centre for Immunology and Allergy Research, Westmead, New South Wales, Australia; and
| | - Jun Yup Lee
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Felix Marsh-Wakefield
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Lai Fong Kok
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Anthony S Don
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Centenary Institute, The University of Sydney, Sydney, New South Wales, Australia
| | - Scott N Byrne
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia; .,Westmead Institute for Medical Research, Centre for Immunology and Allergy Research, Westmead, New South Wales, Australia; and
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7
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Erem AS, Razzaque MS. Vitamin D-independent benefits of safe sunlight exposure. J Steroid Biochem Mol Biol 2021; 213:105957. [PMID: 34329737 DOI: 10.1016/j.jsbmb.2021.105957] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 07/15/2021] [Accepted: 07/25/2021] [Indexed: 01/10/2023]
Abstract
This review examines the beneficial effects of ultraviolet radiation on systemic autoimmune diseases, including multiple sclerosis and type I diabetes, where the epidemiological evidence for the vitamin D-independent effects of sunlight is most apparent. Ultraviolet radiation, in addition to its role in the synthesis of vitamin D, stimulates anti-inflammatory pathways, alters the composition of dendritic cells, T cells, and T regulatory cells, and induces nitric oxide synthase and heme oxygenase metabolic pathways, which may directly or indirectly mitigate disease progression and susceptibility. Recent work has also explored how the immune-modulating functions of ultraviolet radiation affect type II diabetes, cancer, and the current global pandemic caused by SARS-CoV-2. These diseases are particularly important amidst global changes in lifestyle that result in unhealthy eating, increased sedentary habits, and alcohol and tobacco consumption. Compelling epidemiological data shows increased ultraviolet radiation associated with reduced rates of certain cancers, such as colorectal cancer, breast cancer, non-Hodgkins lymphoma, and ultraviolet radiation exposure correlated with susceptibility and mortality rates of COVID-19. Therefore, understanding the effects of ultraviolet radiation on both vitamin D-dependent and -independent pathways is necessary to understand how they influence the course of many human diseases.
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Affiliation(s)
- Anna S Erem
- Department of Pathology, Emory University School of Medicine, Atlanta, GA, USA
| | - Mohammed S Razzaque
- Department of Pathology, Lake Erie College of Osteopathic Medicine, Erie, PA, USA.
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8
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Trend S, Leffler J, Cooper MN, Byrne SN, Kermode AG, French MA, Hart PH. Narrowband UVB phototherapy reduces TNF production by B-cell subsets stimulated via TLR7 from individuals with early multiple sclerosis. Clin Transl Immunology 2020; 9:e1197. [PMID: 33088505 PMCID: PMC7561518 DOI: 10.1002/cti2.1197] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/26/2020] [Accepted: 09/27/2020] [Indexed: 01/21/2023] Open
Abstract
Objectives At the end of a 60‐day course of narrowband UVB phototherapy, administered to individuals with early multiple sclerosis, there were changes in the relative proportions of circulating B‐cell subsets. This study investigated phototherapy‐associated changes to cytokine responses of B cells when exposed to a TLR7 ligand. Methods PBMCs from participants of the PhoCIS (Phototherapy for Clinically Isolated Syndrome) trial taken before (day 1) and after phototherapy for 8 weeks (day 60) were incubated with, or without, the TLR7 ligand, R848, for 18 h. Production of TNF and IL‐10 in seven B‐cell subsets was examined, with cytokine responses in each individual at day 60, adjusted for responses at day 1. Paired PBMCs were from participants administered phototherapy (n = 7) or controls (n = 6). Results At day 60, significantly fewer B cells, particularly marginal zone‐like B cells (CD27+/IgD+), from participants administered phototherapy produced TNF in response to TLR7 stimulation. When responses by seven B‐cell subsets were analysed together using multivariate methods, a phototherapy‐specific signature was observed. An increased responsiveness from day 1 to day 60 in IgM‐only memory B cells (CD27+/IgD−/IgM+) after TLR7 stimulation also predicted slower progression from CIS to MS. Phototherapy was without significant effect on B‐cell IL‐10 production. Conclusions Reduced TNF responses after TLR7 stimulation in marginal zone‐like B cells from participants administered phototherapy suggested treatment‐associated priming effects that were detected upon subsequent polyclonal B‐cell activation. Changes in responsiveness to TLR7 stimulation also suggested that IgM‐only memory B cells may be important in conversion from CIS to MS.
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Affiliation(s)
- Stephanie Trend
- Telethon Kids Institute University of Western Australia Perth WA Australia.,Centre for Neuromuscular and Neurological Disorders Perron Institute for Neurological and Translational Science University of Western Australia Perth WA Australia
| | - Jonatan Leffler
- Telethon Kids Institute University of Western Australia Perth WA Australia
| | - Matthew N Cooper
- Telethon Kids Institute University of Western Australia Perth WA Australia
| | - Scott N Byrne
- School of Medical Sciences Faculty of Medicine and Health The University of Sydney Sydney NSW Australia.,Centre for Immunology and Allergy Research Westmead Institute for Medical Research Westmead NSW Australia
| | - Allan G Kermode
- Centre for Neuromuscular and Neurological Disorders Perron Institute for Neurological and Translational Science University of Western Australia Perth WA Australia.,Institute for Immunology and Infectious Disease Murdoch University Perth WA Australia
| | - Martyn A French
- UWA Medical School and School of Biomedical Sciences University of Western Australia Perth WA Australia
| | - Prue H Hart
- Telethon Kids Institute University of Western Australia Perth WA Australia
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9
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Marsh‐Wakefield F, Ashhurst T, Trend S, McGuire HM, Juillard P, Zinger A, Jones AP, Kermode AG, Hawke S, Grau GE, Hart PH, Byrne SN. IgG 3 + B cells are associated with the development of multiple sclerosis. Clin Transl Immunology 2020; 9:e01133. [PMID: 32355561 PMCID: PMC7190396 DOI: 10.1002/cti2.1133] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVES Disease-modifying therapies (DMTs) targeting B cells are amongst the most effective for preventing multiple sclerosis (MS) progression. IgG3 antibodies and their uncharacterised B-cell clones are predicted to play a pathogenic role in MS. Identifying subsets of IgG3 + B cells involved in MS progression could improve diagnosis, could inform timely disease intervention and may lead to new DMTs that target B cells more specifically. METHODS We designed a 31-parameter B-cell-focused mass cytometry panel to interrogate the role of peripheral blood IgG3 + B cells in MS progression of two different patient cohorts: one to investigate the B-cell subsets involved in conversion from clinically isolated syndrome (CIS) to MS; and another to compare MS patients with inactive or active stages of disease. Each independent cohort included a group of non-MS controls. RESULTS Nine distinct CD20+IgD-IgG3 + B-cell subsets were identified. Significant changes in the proportion of CD21+CD24+CD27-CD38- and CD27+CD38hiCD71hi memory B-cell subsets correlated with changes in serum IgG3 levels and time to conversion from CIS to MS. The same CD38- double-negative B-cell subset was significantly elevated in MS patients with active forms of the disease. A third CD21+CD24+CD27+CD38- subset was elevated in patients with active MS, whilst narrowband UVB significantly reduced the proportion of this switched-memory B-cell subset. CONCLUSION We have identified previously uncharacterised subsets of IgG3 + B cells and shown them to correlate with autoimmune attacks on the central nervous system (CNS). These results highlight the potential for therapies that specifically target IgG3 + B cells to impact MS progression.
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Affiliation(s)
- Felix Marsh‐Wakefield
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
| | - Thomas Ashhurst
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
- Viral Immunopathology LaboratoryDepartment of PathologyThe University of SydneySydneyNSWAustralia
- Ramaciotti Facility for Human Systems BiologyThe University of SydneySydneyNSWAustralia
- Sydney Cytometry FacilityCharles Perkins CentreThe University of Sydney and Centenary InstituteSydneyNSWAustralia
| | - Stephanie Trend
- Telethon Kids InstituteUniversity of Western AustraliaPerthWAAustralia
- Centre for Neuromuscular and Neurological DisordersPerron Institute for Neurological and Translational ScienceUniversity of Western AustraliaPerthWAAustralia
| | - Helen M McGuire
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
- Ramaciotti Facility for Human Systems BiologyThe University of SydneySydneyNSWAustralia
- Translational Immunology LaboratoryDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Pierre Juillard
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Anna Zinger
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Anderson P Jones
- Telethon Kids InstituteUniversity of Western AustraliaPerthWAAustralia
| | - Allan G Kermode
- Centre for Neuromuscular and Neurological DisordersPerron Institute for Neurological and Translational ScienceUniversity of Western AustraliaPerthWAAustralia
- Institute for Immunology and Infectious DiseaseMurdoch UniversityPerthWAAustralia
| | - Simon Hawke
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
- Central West Neurology and NeurosurgeryOrangeNSWAustralia
| | - Georges E Grau
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Prue H Hart
- Telethon Kids InstituteUniversity of Western AustraliaPerthWAAustralia
| | - Scott N Byrne
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
- Centre for Immunology and Allergy ResearchWestmead Institute for Medical ResearchWestmeadNSWAustralia
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10
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Marsh-Wakefield F, Byrne SN, Hawke S, Grau G. Mass cytometry provides unprecedented insight into the role of B cells during the pathogenesis of multiple sclerosis. ADVANCES IN CLINICAL NEUROSCIENCE & REHABILITATION 2020. [DOI: 10.47795/fzhz8873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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11
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Kok LF, Ferguson AL, Marshall JE, Tse BCY, Halliday GM, Byrne SN. B Cell-Targeted Immunotherapy Limits Tumor Growth, Enhances Survival, and Prevents Lymph Node Metastasis of UV-Induced Keratinocyte Cancers in Mice. J Invest Dermatol 2020; 140:1459-1463. [PMID: 31954726 DOI: 10.1016/j.jid.2019.12.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/18/2019] [Accepted: 12/23/2019] [Indexed: 12/28/2022]
Affiliation(s)
- Lai-Fong Kok
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Angela L Ferguson
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia; Centenary Institute, The University of Sydney, Sydney, New South Wales, Australia
| | - Jacqueline E Marshall
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia; Centenary Institute, The University of Sydney, Sydney, New South Wales, Australia
| | - Benita C Y Tse
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Gary M Halliday
- Dermatology Research Laboratories, Central Clinical School, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Scott N Byrne
- School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia; Westmead Institute for Medical Research, Centre for Immunology and Allergy Research, Sydney, New South Wales, Australia.
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12
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Debes GF, McGettigan SE. Skin-Associated B Cells in Health and Inflammation. THE JOURNAL OF IMMUNOLOGY 2020; 202:1659-1666. [PMID: 30833422 DOI: 10.4049/jimmunol.1801211] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 10/29/2018] [Indexed: 12/13/2022]
Abstract
Traditionally, the skin was believed to be devoid of B cells, and studies of the skin immune system have largely focused on other types of leukocytes. Exciting recent data show that B cells localize to the healthy skin of humans and other mammalian species with likely homeostatic functions in host defense, regulation of microbial communities, and wound healing. Distinct skin-associated B cell subsets drive or suppress cutaneous inflammatory responses with important clinical implications. Localized functions of skin-associated B cell subsets during inflammation comprise Ab production, interactions with skin T cells, tertiary lymphoid tissue formation, and production of proinflammatory cytokines but also include immunosuppression by providing IL-10. In this review, we delve into the intriguing new roles of skin-associated B cells in homeostasis and inflammation.
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Affiliation(s)
- Gudrun F Debes
- Department of Microbiology and Immunology, Sidney Kimmel Medical College, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107
| | - Shannon E McGettigan
- Department of Microbiology and Immunology, Sidney Kimmel Medical College, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107
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13
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Tse BCY, Byrne SN. Lipids in ultraviolet radiation-induced immune modulation. Photochem Photobiol Sci 2020; 19:870-878. [DOI: 10.1039/d0pp00146e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Ultraviolet (UV) radiation modulates cutaneous lipids which in turn mediates immune suppression – a key mechanism conferring both detrimental and beneficial impacts of sun exposure on human health.
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Affiliation(s)
- Benita C. Y. Tse
- The University of Sydney
- School of Medical Sciences
- Faculty of Medicine and Health
- Sydney
- Australia
| | - Scott N. Byrne
- The University of Sydney
- School of Medical Sciences
- Faculty of Medicine and Health
- Sydney
- Australia
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14
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Short-term changes in frequencies of circulating leukocytes associated with narrowband UVB phototherapy in people with clinically isolated syndrome. Sci Rep 2019; 9:7980. [PMID: 31138860 PMCID: PMC6538725 DOI: 10.1038/s41598-019-44488-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 05/17/2019] [Indexed: 12/18/2022] Open
Abstract
Clinically isolated syndrome (CIS) is the earliest clinical episode in multiple sclerosis (MS). Low environmental exposure to UV radiation is implicated in risk of developing MS, and therefore, narrowband UVB phototherapy might delay progression to MS in people with CIS. Twenty individuals with CIS were recruited, and half were randomised to receive 24 sessions of narrowband UVB phototherapy over a period of 8 weeks. Here, the effects of narrowband UVB phototherapy on the frequencies of circulating immune cells and immunoglobulin levels after phototherapy are reported. Peripheral blood samples for all participants were collected at baseline, and 1, 2, 3, 6 and 12 months after enrolment. An extensive panel of leukocyte populations, including subsets of T cells, B cells, monocytes, dendritic cells, and natural killer cells were examined in phototherapy-treated and control participants, and immunoglobulin levels measured in serum. There were significant short-term increases in the frequency of naïve B cells, intermediate monocytes, and fraction III FoxP3+ T regulatory cells, and decreases in switched memory B cells and classical monocytes in phototherapy-treated individuals. Since B cells are increasingly targeted by MS therapies, the effects of narrowband UVB phototherapy in people with MS should be investigated further.
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15
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Hart PH, Norval M, Byrne SN, Rhodes LE. Exposure to Ultraviolet Radiation in the Modulation of Human Diseases. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2018; 14:55-81. [PMID: 30125148 DOI: 10.1146/annurev-pathmechdis-012418-012809] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review focuses primarily on the beneficial effects for human health of exposure to ultraviolet radiation (UVR). UVR stimulates anti-inflammatory and immunosuppressive pathways in skin that modulate psoriasis, atopic dermatitis, and vitiligo; suppresses cutaneous lesions of graft-versus-host disease; and regulates some infection and vaccination outcomes. While polymorphic light eruption and the cutaneous photosensitivity of systemic lupus erythematosus are triggered by UVR, polymorphic light eruption also frequently benefits from UVR-induced immunomodulation. For systemic diseases such as multiple sclerosis, type 1 diabetes, asthma, schizophrenia, autism, and cardiovascular disease, any positive consequences of UVR exposure are more speculative, but could occur through the actions of UVR-induced regulatory cells and mediators, including 1,25-dihydroxy vitamin D3, interleukin-10, and nitric oxide. Reduced UVR exposure is a risk factor for the development of several inflammatory, allergic, and autoimmune conditions, including diseases initiated in early life. This suggests that UVR-induced molecules can regulate cell maturation in developing organs.
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Affiliation(s)
- Prue H Hart
- Telethon Kids Institute, University of Western Australia, Perth, Western Australia 6008, Australia;
| | - Mary Norval
- University of Edinburgh Medical School, Edinburgh EH8 9AG, United Kingdom;
| | - Scott N Byrne
- Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales 2006, Australia; .,Westmead Institute for Medical Research, Westmead, New South Wales 2145, Australia
| | - Lesley E Rhodes
- Centre for Dermatology Research, Division of Musculoskeletal and Dermatological Sciences, School of Biological Sciences, and Faculty of Biology, Medicine, and Health, The University of Manchester and Salford Royal NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M13 9PL, United Kingdom;
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16
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Abstract
The Ultraviolet (UV) radiation contained in sunlight is a powerful mutagen and immune suppressant which partly explains why exposure to solar UV is the biggest risk factor for the development of cutaneous tumours. Evidence is building that sunlight may be protective against some internal malignancies. Because patients with these tumours are often vitamin D deficient, this has led some to propose that vitamin D supplementation will be beneficial in the treatment of these cancers. However, the results from already completed trials have been disappointing which has given weight to the argument that there must be something else about sunlight that explains its cancer-protecting properties.
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Affiliation(s)
- Jacqueline E Marshall
- Cellular Photoimmunology Group, Discipline of Infectious Diseases and Immunology, Sydney Medical School at the Charles Perkins Centre, University of Sydney, Australia.
| | - Scott N Byrne
- Cellular Photoimmunology Group, Discipline of Infectious Diseases and Immunology, Sydney Medical School at the Charles Perkins Centre, University of Sydney, Australia.
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17
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Abstract
The number of peer-reviewed articles published during the 2016 solar year and retrieved using the "autoimmunity" key word remained stable while gaining a minimal edge among the immunology articles. Nonetheless, the quality of the publications has been rising significantly and, importantly, acquisitions have become available through scientific journals dedicated to immunology or autoimmunity. Major discoveries have been made in the fields of systemic lupus erythematosus, rheumatoid arthritis, autoimmunity of the central nervous system, vasculitis, and seronegative spondyloarthrithritides. Selected examples include the role of IL17-related genes and long noncoding RNAs in systemic lupus erythematosus or the effects of anti-pentraxin 3 (PTX3) in the treatment of this paradigmatic autoimmune condition. In the case of rheumatoid arthritis, there have been reports of the role of induced regulatory T cells (iTregs) or fibrocytes and T cell interactions with exciting implications. The large number of studies dealing with neuroimmunology pointed to Th17 cells, CD56(bright) NK cells, and low-level TLR2 ligands as involved in multiple sclerosis, along with a high salt intake or the micriobiome-derived Lipid 654. Lastly, we focused on the rare vasculitides to which numerous studies were devoted and suggested that unsuspected cell populations, including monocytes, mucosal-associated invariant T cells, and innate lymphoid cells, may be crucial to ANCA-associated manifestations. This brief and arbitrary discussion of the findings published in 2016 is representative of a promising background for developments that will enormously impact the work of laboratory scientists and physicians at an exponential rate.
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Affiliation(s)
- Carlo Selmi
- Division of Rheumatology and Clinical Immunology, Humanitas Research Hospital, via A. Manzoni 56, 20089, Rozzano, Milan, Italy.
- Department of Medical Biotechnologies and Translational Medicine (BIOMETRA), University of Milan, Milan, Italy.
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18
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Hart PH, Lucas RM, Booth DR, Carroll WM, Nolan D, Cole JM, Jones AP, Kermode AG. Narrowband UVB Phototherapy for Clinically Isolated Syndrome: A Trial to Deliver the Benefits of Vitamin D and Other UVB-Induced Molecules. Front Immunol 2017; 8:3. [PMID: 28167940 PMCID: PMC5256075 DOI: 10.3389/fimmu.2017.00003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 01/03/2017] [Indexed: 01/16/2023] Open
Abstract
Low vitamin D and insufficient sun exposure are additive independent risk factors for the development of multiple sclerosis (MS). The usual measure of vitamin D status, serum 25-hydroxy vitamin D [25(OH)D], is also a marker of recent exposure to the UVB rays of sunshine. The main evidence for a protective effect for MS development of higher 25(OH)D comes from observational studies, but this study design cannot separate out whether 25(OH)D is acting as a marker of vitamin D status, sun exposure, or both. In light of a lack of definitive outcomes in MS patients after trials of vitamin D supplementation and the ability of narrowband UVB to induce vitamin D, as well as other immune-regulatory molecules in skin, the Phototherapy for Clinically Isolated Syndrome (PhoCIS) trial was established to investigate the benefits of narrowband UVB, in addition to supplemented vitamin D, on MS development in individuals with Clinically Isolated Syndrome. We propose that the PhoCIS trial provides a fresh approach to re-defining the reported associations of 25(OH)D levels with MS development and progression.
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Affiliation(s)
- Prue H Hart
- Telethon Kids Institute, University of Western Australia , Perth, WA , Australia
| | - Robyn M Lucas
- Telethon Kids Institute, University of Western Australia, Perth, WA, Australia; National Centre for Epidemiology and Public Health, Research School of Population Health, Australian National University, Canberra, ACT, Australia
| | - David R Booth
- The Westmead Institute for Medical Research, University of Sydney , Westmead, NSW , Australia
| | - William M Carroll
- Centre for Neuromuscular and Neurological Disorders, Western Australian Neuroscience Research Institute, University of Western Australia, Sir Charles Gairdner Hospital , Perth, WA , Australia
| | - David Nolan
- Institute for Immunology and Infectious Disease, Murdoch University, Perth, WA, Australia; Royal Perth Hospital, Immunology Department, Perth, WA, Australia
| | - Judith M Cole
- St John of God Dermatology , Subiaco, WA , Australia
| | - Anderson P Jones
- Telethon Kids Institute, University of Western Australia , Perth, WA , Australia
| | - Allan G Kermode
- Centre for Neuromuscular and Neurological Disorders, Western Australian Neuroscience Research Institute, University of Western Australia, Sir Charles Gairdner Hospital, Perth, WA, Australia; Institute for Immunology and Infectious Disease, Murdoch University, Perth, WA, Australia
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19
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Irving AA, Marling SJ, Plum LA, DeLuca HF. Suppression of experimental autoimmune encephalomyelitis by ultraviolet light is not mediated by isomerization of urocanic acid. BMC Neurosci 2017; 18:8. [PMID: 28056806 PMCID: PMC5217575 DOI: 10.1186/s12868-016-0323-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 12/14/2016] [Indexed: 11/14/2022] Open
Abstract
Background Ultraviolet B irradiation confers strong resistance against experimental autoimmune encephalomyelitis, a model of multiple sclerosis. This protection by ultraviolet B is independent of vitamin D production but causes isomerization of urocanic acid, a naturally occurring immunosuppressant. Methods To determine whether UCA isomerization from trans to cis is responsible for the protection against experimental autoimmune encephalomyelitis afforded by ultraviolet B, trans- or cis-urocanic acid was administered to animals and their disease progression was monitored. Results Disease incidence was reduced by 74% in animals exposed to ultraviolet B, and skin cis-urocanic acid levels increased greater than 30%. However, increasing skin cis-urocanic acid levels independent of ultraviolet B was unable to alter disease onset or progression. Conclusions It is unlikely that urocanic acid isomerization is responsible for the ultraviolet B-mediated suppression of experimental autoimmune encephalomyelitis. Additional work is needed to investigate alternative mechanisms by which UVB suppresses disease.
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Affiliation(s)
- Amy A Irving
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Steven J Marling
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Lori A Plum
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Hector F DeLuca
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA.
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