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Ceccato E, Cramp RL, Seebacher F, Franklin CE. Early exposure to ultraviolet-B radiation decreases immune function later in life. CONSERVATION PHYSIOLOGY 2016; 4:cow037. [PMID: 27668081 PMCID: PMC5033135 DOI: 10.1093/conphys/cow037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 08/12/2016] [Accepted: 08/18/2016] [Indexed: 05/23/2023]
Abstract
Amphibians have declined dramatically worldwide. Many of these declines are occurring in areas where no obvious anthropogenic stressors are present. It is proposed that in these areas, environmental factors such as elevated solar ultraviolet-B (UV-B) radiation could be responsible. Ultraviolet-B levels have increased in many parts of the world as a consequence of the anthropogenic destruction of the ozone layer. Amphibian tadpoles are particularly sensitive to the damaging effects of UV-B radiation, with exposure disrupting growth and fitness in many species. Given that UV-B can disrupt immune function in other animals, we tested the hypothesis that early UV-B exposure suppresses the immune responses of amphibian tadpoles and subsequent juvenile frogs. We exposed Limnodynastes peronii tadpoles to sublethal levels of UV-B radiation for 6 weeks after hatching, then examined indices of immune function in both the tadpoles and the subsequent metamorphs. There was no significant effect of UV-B on tadpole leucocyte counts or on their response to an acute antigen (phytohaemagglutinin) challenge. However, early UV-B exposure resulted in a significant reduction in both metamorph leucocyte abundance and their response to an acute phytohaemagglutinin challenge. These data demonstrate that early UV-B exposure can have carry-over effects on later life-history traits even if the applied stressor has no immediately discernible effect. These findings have important implications for our understanding of the effects of UV-B exposure on amphibian health and susceptibility to diseases such as chytridiomycosis.
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Affiliation(s)
- Emma Ceccato
- School of Biological Sciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - Rebecca L. Cramp
- School of Biological Sciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - Frank Seebacher
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
| | - Craig E. Franklin
- School of Biological Sciences, University of Queensland, Brisbane, QLD 4072, Australia
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Martinez-Levasseur LM, Furgal CM, Hammill MO, Burness G. Towards a Better Understanding of the Effects of UV on Atlantic Walruses, Odobenus rosmarus rosmarus: A Study Combining Histological Data with Local Ecological Knowledge. PLoS One 2016; 11:e0152122. [PMID: 27049757 PMCID: PMC4822789 DOI: 10.1371/journal.pone.0152122] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 03/09/2016] [Indexed: 12/21/2022] Open
Abstract
Walruses, Odobenus rosmarus, play a key role in the Arctic ecosystem, including northern Indigenous communities, which are reliant upon walruses for aspects of their diet and culture. However, walruses face varied environmental threats including rising sea-water temperatures and decreasing ice cover. An underappreciated threat may be the large amount of solar ultraviolet radiation (UV) that continues to reach the Arctic as a result of ozone loss. UV has been shown to negatively affect whales. Like whales, walrus skin is unprotected by fur, but in contrast, walruses spend long periods of time hauled-out on land. In this study, we combined the results of histological analyses of skin sections from five Atlantic walruses, Odobenus rosmarus rosmarus, collected in Nunavik (Northern Quebec, Canada) with qualitative data obtained through the interviews of 33 local walrus hunters and Inuit Elders. Histological analyses allowed us to explore UV-induced cellular lesions and interviews with experienced walrus hunters and Elders helped us to study the incidences and temporal changes of UV-induced gross lesions in walruses. At the microscopic scale, we detected a range of skin abnormalities consistent with UV damage. However, currently such UV effects do not seem to be widely observed at the whole-animal level (i.e., absence of skin blistering, erythema, eye cataract) by individuals interviewed. Although walruses may experience skin damage under normal everyday UV exposure, the long-term data from local walrus hunters and Inuit Elders did not report a relation between the increased sun radiation secondary to ozone loss and walrus health.
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Affiliation(s)
- Laura M. Martinez-Levasseur
- Department of Biology, Trent University, Peterborough, Ontario, Canada
- Department of Indigenous Studies, Trent University, Peterborough, Ontario, Canada
- * E-mail: (GB); (LMML)
| | - Chris M. Furgal
- Department of Indigenous Studies, Trent University, Peterborough, Ontario, Canada
- Environmental Resource Studies and Sciences, Trent University, Peterborough, Ontario, Canada
| | - Mike O. Hammill
- Maurice Lamontagne Institute, Fisheries and Oceans Canada, Mont-Joli, Quebec, Canada
| | - Gary Burness
- Department of Biology, Trent University, Peterborough, Ontario, Canada
- * E-mail: (GB); (LMML)
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Stirling RJ, Haslam JD. A self-reported clinical trial investigates the efficacy of 1072 nm light as an anti-ageing agent. J COSMET LASER THER 2008; 9:226-30. [PMID: 17852628 DOI: 10.1080/14764170701400085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
BACKGROUND Previous laboratory research has shown that human lymphocytes pre-irradiated with 1072 nm light are afforded some protection against subsequent ultraviolet light toxicity. OBJECTIVE To investigate the possibility that 1072 nm light can prevent or reverse skin ageing which itself is known to be accelerated by ultraviolet light. METHODS A randomized, prospective, double-blind, placebo-controlled, self-reporting study was performed to assess the effect of one daily treatment episode for a period of between 6 and 8 weeks on wrinkles and fine lines around the eyes as well as the appearance of bags under the eyes. RESULTS Between 52% and 57% of volunteers were able to accurately identify an improvement in the fine lines and wrinkles of the treated areas of skin. Fewer volunteers, between 37% and 46%, observed an improvement in the bags under the treated eye or eyes, albeit with an emphatic statistical significance. CONCLUSION Regular application of a non-thermal quantity of 1072nm light around the eyes demonstrated efficacy as an anti-ageing agent.
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Affiliation(s)
- Richard J Stirling
- Department of Ophthalmology, Darlington Memorial Hospital, County Durham, UK
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Abstract
Around 1980, experiments with hairless mice showed us that UV-induced actinic keratoses (AK) and ensuing skin carcinomas did not arise independently: the rate of occurrence in one skin area was increased considerably if AKs had already been induced separately in another distant skin area, i.e. a systemic effect. The ground laying work of Margaret Kripke in the 1970s provided a fitting explanation: UV-induced immunosuppression and tolerance toward the UV-induced tumors. From Kripke's work a new discipline arose: "Photoimmunology." Enormous strides were made in exploring and expanding the effects from UV carcinogenesis to infectious diseases, and in elucidating the mechanisms involved. Stemming from concerns about a depletion of the ozone layer and the general impact of ambient UV radiation, the groups I worked in and closely collaborated with explored the anticipated adverse effects of UV-induced immunosuppression on healthy individuals. An important turning point was brought about in 1992 when the group of Kevin Cooper reported that immunosuppression could be induced by UV exposure in virtually all human subjects tested, suggesting that this is a normal and sound physiological reaction to UV exposure. This reaction could actually protect us from illicit immune responses against our UV-exposed skin, such as observed in idiopathic polymorphic light eruption. This premise has fruitfully rekindled the research on this common "sun allergy," affecting to widely varying degrees about one in five Europeans with indoor professions.
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Affiliation(s)
- Frank R de Gruijl
- Dermatology, Leiden University Medical Center, Leiden, The Netherlands.
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Ryan LK, Neldon DL, Bishop LR, Gilmour MI, Daniels MJ, Sailstad DM, Selgrade MJK. Exposure to Ultraviolet Radiation Enhances Mortality and Pathology Associated with Influenza Virus Infection in Mice¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2000)0720497eturem2.0.co2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Jokinen EI, Salo HM, Markkula SE, Immonen AK, Aaltonen TM. Ultraviolet B Irradiation Modulates the Immune System of Fish (Rutilus rutilus, Cyprinidae) Part III: Lymphocytes¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2001)0730505ubimti2.0.co2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Markkula SE, Salo HM, Immonen AK, Jokinen EI. Effects of Short- and Long-term Ultraviolet B Irradiation on the Immune System of the Common Carp (Cyprinus carpio)¶. Photochem Photobiol 2007. [DOI: 10.1111/j.1751-1097.2005.tb00231.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Hargate G. A randomised double-blind study comparing the effect of 1072-nm light against placebo for the treatment of herpes labialis. Clin Exp Dermatol 2006; 31:638-41. [PMID: 16780494 DOI: 10.1111/j.1365-2230.2006.02191.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Previous research demonstrated that 1072-nm narrowband laser light is effective in the treatment of cold sores. AIM To evaluate the efficacy of an over-the-counter cold-sore treatment device (Virulite CS) incorporating 1072-nm light-emitting diodes. METHODS A randomised, prospective, double-blind, self-reported study was performed to compare the efficacy of at least six 3-min treatments of 1072-nm narrowband light against placebo, in the treatment of herpes labialis. RESULTS The 1072-nm light-emitting diode device reduced cold-sore healing time to 6.3 days compared with 9.4 days for placebo (P=0.048). The time the cold sore took to form a crust was also reduced from 2.00 days for those treated with 1072-nm light, compared with 2.88 days for placebo (P=0.059) CONCLUSIONS The significant difference between the mean healing times in the two groups demonstrates that the Virulite CS device is an effective means of treating herpes labialis.
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Affiliation(s)
- G Hargate
- Newlands Medical Centre, Borough Road, Middlesbrough, UK.
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Ismail A, Khalil EAG, Musa AM, El Hassan IM, Ibrahim ME, Theander TG, El Hassan AM. The pathogenesis of post kala-azar dermal leishmaniasis from the field to the molecule: Does ultraviolet light (UVB) radiation play a role? Med Hypotheses 2006; 66:993-9. [PMID: 16386855 DOI: 10.1016/j.mehy.2005.03.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2005] [Revised: 02/11/2005] [Accepted: 03/10/2005] [Indexed: 11/27/2022]
Abstract
Post kala-azar dermal leishmaniasis (PKDL) is a dermatosis caused by persistence of Leishmania donovani parasites in the skin following apparently successful treatment of visceral leishmaniasis. The distribution of PKDL lesions in Sudanese patients often mirrors the clothing habits of those affected. It is most severe in or confined to the sun-exposed parts of the skin. It is well established that elimination of Leishmania parasites requires activation of parasitised macrophages by a Th1 immune response and that the latter is depressed by ultraviolet light (UVB). In this paper, we hypothesized that UVB light might be a key player in the pathogenesis of PKDL. This paper links observations made in the field with immunological data that are compatible with this hypothesis. We therefore investigated patients with PKDL immunologically for a possible role of UVB exposure in the pathogenesis of this condition. We marshal evidence that the changes in the tissues are compatible with the effects of UVB light and it is probable that UVB appears to be a key factor in the pathogenesis of PKDL. Immunopathologically the lesions were characterized by an influx of various inflammatory cells. The number of CD1a (Langerhans' cells) was decreased, they lost their dendrites, their HLA-DR and B7-1 expression was down regulated while B7-2 was expressed. Others have shown that Langerhans' cells with these features result from UVB exposure and that such cells are unable to present antigen to Th1 cells while retaining the capacity to present antigen to Th2 cells. Various cytokines known to be induced by UVB radiation could be demonstrated in PKDL lesions. Of these IL-10, TGF-beta, IL-12, IL-4 and TNF-alpha were found in different quantities. The Th-1 cytokine IFN-gamma was constantly present. The tissue origin of the Th-1 cells in PKDL is unknown. We believe that the antagonistic action of the different cytokines is the cause of the inflammation and chronicity of PKDL.
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Affiliation(s)
- A Ismail
- Department of Clinical Pathology and Immunology, Faculty of Medicine, Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Sudan.
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Markkula SE, Salo HM, Immonen AK, Jokinen EI. Effects of Short- and Long-term Ultraviolet B Irradiation on the Immune System of the Common Carp (Cyprinus carpio)¶. Photochem Photobiol 2005. [DOI: 10.1562/2004-07-13-ra-231.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Sleijffers A, Yucesoy B, Kashon M, Garssen J, De Gruijl FR, Boland GJ, Van Hattum J, Luster MI, Van Loveren H. Cytokine polymorphisms play a role in susceptibility to ultraviolet B-induced modulation of immune responses after hepatitis B vaccination. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:3423-8. [PMID: 12626603 DOI: 10.4049/jimmunol.170.6.3423] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
UVB exposure can alter immune responses in experimental animals and humans. In an earlier human volunteer study, we demonstrated that hepatitis B-specific humoral and cellular immunity after vaccination on average were not significantly affected by UVB exposure. However, it is known that individuals differ in their susceptibility to UVB-induced immunomodulation, and it was hypothesized that polymorphisms in specific cytokines may play a role in this susceptibility. In this respect, we previously demonstrated that immune responses after hepatitis B vaccination are influenced by the minor allelic variant of IL-1 beta in the general population. For all volunteers, single nucleotide polymorphisms were determined for the following UV response-related cytokines: IL-1 receptor antagonist (+2018), IL-1 alpha (+4845), IL-1 beta (+3953), TNF-alpha (-308), and TNF-alpha (-238). Exposure to UVB significantly suppressed Ab responses to hepatitis B in individuals with the minor variant for the IL-1 beta polymorphism. Increased minimal erythema dose values (just perceptible), which resulted in higher absolute UVB exposures, were observed in the same individuals. There were no associations observed between UVB-induced immunomodulation and the other cytokine polymorphisms examined. This study indicates that individual susceptibility to UVB radiation needs to be considered when studying the effects of UVB in humans.
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Affiliation(s)
- Annemarie Sleijffers
- National Institute of Public Health and the Environment, Bilthoven, The Netherlands.
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Sleijffers A, Garssen J, Van Loveren H. Ultraviolet radiation, resistance to infectious diseases, and vaccination responses. Methods 2002; 28:111-21. [PMID: 12231195 DOI: 10.1016/s1046-2023(02)00215-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Exposure to ultraviolet (UV) radiation, as in sunlight, can modulate immune responses in animals and humans. This immunomodulation can lead to positive health effects especially with respect to certain autoimmune diseases and allergies. However, UV-induced immunomodulation has also been shown to be deleterious. Experimental animal studies have revealed that UV exposure can impair resistance to many infectious agents, such as bacteria, parasites, viruses, and fungi. Importantly, these effects are not restricted to skin-associated infections, but also concern systemic infections. The real consequences of UV-induced immunomodulation on resistance to infectious diseases are not known for humans. Risk estimations have been performed through extrapolation of animal data, obtained from infection models, to the human situation. This estimation indicated that UV doses relevant to outdoor exposure can impair the human immune system sufficiently to have effects on resistance to infections. To further quantify and validate this risk estimation, data, e.g., from human volunteer studies, are necessary. Infection models in humans are not allowed for ethical reasons. However, vaccination against an infectious disease evokes a similar immune response as the pathogen and thereby provides an opportunity to measure the effect of UV radiation on the immune system and an estimate of the possible consequences of altered resistance to infectious agents. Effects of controlled UVB exposure on immune responses after hepatitis B vaccination have been established in mice and human volunteers. In mice, cellular and Th1-associated humoral immune responses to hepatitis B were significantly impaired, whereas in human volunteers no significant effect of UVB on these responses could be found. Preliminary data indicate that cytokine polymorphisms might be, at least in part, responsible for interindividual differences in immune responses and in susceptibility to UVB-induced immunomodulation. In addition, adaptation to UV exposure needs to be considered as a possible explanation for the difference between mice and humans that was observed in the hepatitis B vaccination model.
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Affiliation(s)
- Annemarie Sleijffers
- National Institute of Public Health and the Environment, P.O. Box 1, 3720 BA, Bilthoven, The Netherlands.
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Clydesdale GJ, Dandie GW, Muller HK. Ultraviolet light induced injury: immunological and inflammatory effects. Immunol Cell Biol 2001; 79:547-68. [PMID: 11903614 DOI: 10.1046/j.1440-1711.2001.01047.x] [Citation(s) in RCA: 383] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
This article reviews many of the complex events that occur after cutaneous ultraviolet (UV) exposure. The inflammatory changes of acute exposure of the skin include erythema (sunburn), the production of inflammatory mediators, alteration of vascular responses and an inflammatory cell infiltrate. Damage to proteins and DNA accumulates within skin cells and characteristic morphological changes occur in keratinocytes and other skin cells. When a cell becomes damaged irreparably by UV exposure, cell death follows via apoptotic mechanisms. Alterations in cutaneous and systemic immunity occur as a result of the UV-induced inflammation and damage, including changes in the production of cytokines by keratinocytes and other skin-associated cells, alteration of adhesion molecule expression and the loss of APC function within the skin. These changes lead to the generation of suppressor T cells, the induction of antigen-specific immunosuppression and a lowering of cell-mediated immunity. These events impair the immune system's capacity to reject highly antigenic skin cancers. This review gives an overview of the acute inflammatory and immunological events associated with cutaneous UV exposure, which are important to consider before dealing with the complex interactions that occur with chronic UV exposure, leading to photocarcinogenesis.
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Affiliation(s)
- G J Clydesdale
- Discipline of Pathology, University of Tasmania, Hobart, Tasmania, Australia
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Ryan LK, Neldon DL, Bishop LR, Gilmour MI, Daniels MJ, Sailstad DM, Selgrade MJ. Exposure to ultraviolet radiation enhances mortality and pathology associated with influenza virus infection in mice. Photochem Photobiol 2000; 72:497-507. [PMID: 11045721 DOI: 10.1562/0031-8655(2000)072<0497:eturem>2.0.co;2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ultraviolet radiation (UVR) causes systemic immune suppression, decreasing the delayed type and contact hypersensitivity responses in animals and humans and enhancing certain mycobacterial, parasitic and viral infections in mice. This study tests the hypothesis that prior exposure to UVR enhances influenza infections in mice. BALB/c female mice were exposed to 0-8.2 kJ/m2 of UVR. Exposed and unexposed mice were infected intranasally three days later with 150-300 plaque-forming units/mouse (lethal dose (LD)20-LD40) of mouse-adapted Hong Kong Influenza A/68 (H3N2) virus or sham infected with 50 microL Hanks' balanced salt solution/mouse. Mortality from viral infection ranged from 25-50%. UVR exposure increased virus-associated mortality in a dose-dependent manner (up to a two-fold increase at 8.2 kJ/m2). The increased mortality was not associated with bacterial pneumonia. The highest dose of UVR also accelerated the body weight loss and increased the severity and incidence of thymic atrophy associated with influenza infection. However, UVR treatment had little effect on the increase in lung wet weight seen with viral infection, and, to our surprise, did not cause an increase in virus titers in the lung or dissemination of virus. The mice died 5-6 days after infection, too early for adaptive immune responses to have much impact. Also, UVR did not interfere with the development of protective immunity to influenza, as measured by reinfection with a lethal challenge of virus. Also, cells adoptively transferred from UVR or untreated mice were equally protective of recipient mice challenged with a lethal dose of virus. The mice resemble mice succumbing to endotoxin, and influenza infection increased the levels of tumor necrosis factor alpha (TNF-alpha) in bronchoalveolar lavage fluid and serum cortisol levels; however, UVR preexposure did not increase either of these responses to the virus. The results show that UVR increased the morbidity, mortality and pathogenesis of influenza virus in mice without affecting protective immunity to the virus, as measured by resistance to reinfection. The mechanism of enhanced mortality is uncertain, but the data raises concerns that UVR may exacerbate early responses that contribute to the pathogenesis of a primary viral infection.
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Affiliation(s)
- L K Ryan
- Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
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Salo HM, Aaltonen TM, Markkula SE, Jokinen EI. Ultraviolet B Irradiation Modulates the Immune System of Fish (Rutilus rutilus, Cyprinidae). I. Phagocytes. Photochem Photobiol 1998. [DOI: 10.1111/j.1751-1097.1998.tb05223.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Goettsch W, Garssen J, de Klerk A, Herremans TM, Dortant P, de Gruijl FR, Van Loveren H. Effects of ultraviolet-B exposure on the resistance to Listeria monocytogenes in the rat. Photochem Photobiol 1996; 63:672-9. [PMID: 8628759 DOI: 10.1111/j.1751-1097.1996.tb05672.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A rat infection model using the bacterial pathogen Listeria monocytogenes was employed to analyze the immunosuppressive activity of UVB radiation. Rats were exposed to suberythemal doses of UVB radiation for 5 or 7 consecutive days, using Kromayer or FS40 lamps respectively. Subsequently, the rats were infected subcutaneously or intravenously with Listeria. Exposure to UVB resulted in an increased number of bacteria in the spleen 4 days after infection. Listeria-specific lymphocyte proliferation assays as well as delayed-type hypersensitivity reactions demonstrated that T cell-mediated immunity to Listeria was impaired by UVB as measured 4 and 8 days after infection. In addition, UVB exposure decreased phagocytotic activity of peripheral blood macrophages. This study demonstrated that suberythemal doses of UVB radiation caused a delay in the clearance of Listeria bacteria from the spleen of the rats and that this was probably caused by impaired nonspecific phagocytosis of Listeria by macrophages in addition to an impaired activity of Listeria-specific T cells.
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Affiliation(s)
- W Goettsch
- National Institute of Public Health and the Environment, Bilthoven, The Netherlands
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UVB can affect the immune system resulting in decreased resistance to infections and tumors. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/s0166-1116(06)80125-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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