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Retzinger AC, Retzinger GS. The Acari Hypothesis, IV: revisiting the role of hygiene in allergy. FRONTIERS IN ALLERGY 2024; 5:1415124. [PMID: 39055609 PMCID: PMC11270752 DOI: 10.3389/falgy.2024.1415124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 06/21/2024] [Indexed: 07/27/2024] Open
Abstract
Allergy and its manifestations were first appreciated in the 1870 s. Today, the mechanism by which specific substances elicit allergic reactions remains poorly understood. This is problematic from a healthcare perspective because the prevalence of allergic disease and its societal costs are substantial. Regarding mechanistic understanding of allergy, a new proposal, The Acari Hypothesis, has been forwarded. The Hypothesis, borne from consideration of alpha-gal syndrome, postulates that acarians, i.e., mites and ticks, are operative agents of allergy. By way of their pathogenic payloads and salivary pattern recognition receptor(s), acarians potentiate in human hosts the generation of IgE against acarian dietary elements. Those elements account for most, if not all, known human allergens. Inasmuch as acarian-human interactions occur on human epithelial surfaces, it is to be expected factors that influence the presence and/or operation of acarians on those surfaces influence the expression of allergic diseases. In this report, it is proposed that two adaptations of catarrhine primates, i.e., Old World monkeys, apes and humans, evolved to deter acarian species: firstly, the expansion of eccrine glands across the entirety of body surface area, and, secondly, the secretion of sweat by those glands. Contemporary hygienic practices that reduce and/or disrupt the operation of eccrine glands are likely responsible for the increase in allergic disease seen today.
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Affiliation(s)
- Andrew C. Retzinger
- Department of Emergency Medicine, Camden Clark Medical Center, West Virginia University, Parkersburg, WV, United States
| | - Gregory S. Retzinger
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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2
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Bácsi A, Ágics B, Pázmándi K, Kocsis B, Sándor V, Bertók L, Bruckner G, Sipka S. Radiation-Detoxified Form of Endotoxin Effectively Activates Th 1 Responses and Attenuates Ragweed-Induced Th 2-Type Airway Inflammation in Mice. Int J Mol Sci 2024; 25:1581. [PMID: 38338861 PMCID: PMC10855154 DOI: 10.3390/ijms25031581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/24/2024] [Accepted: 01/25/2024] [Indexed: 02/12/2024] Open
Abstract
Urbanization with reduced microbial exposure is associated with an increased burden of asthma and atopic symptoms. Conversely, environmental exposure to endotoxins in childhood can protect against the development of allergies. Our study aimed to investigate whether the renaturation of the indoor environment with aerosolized radiation-detoxified lipopolysaccharide (RD-LPS) has a preventative effect against the development of ragweed-induced Th2-type airway inflammation. To explore this, cages of six-week-old BALB/c mice were treated daily with aerosolized native LPS (N-LPS) or RD-LPS. After a 10-week treatment period, mice were sensitized and challenged with ragweed pollen extract, and inflammatory cell infiltration into the airways was observed. As dendritic cells (DCs) play a crucial role in the polarization of T-cell responses, in our in vitro experiments, the effects of N-LPS and RD-LPS were compared on human monocyte-derived DCs (moDCs). Mice in RD-LPS-rich milieu developed significantly less allergic airway inflammation than mice in N-LPS-rich or common environments. The results of our in vitro experiments demonstrate that RD-LPS-exposed moDCs have a higher Th1-polarizing capacity than moDCs exposed to N-LPS. Consequently, we suppose that the aerosolized, non-toxic RD-LPS applied in early life for the renaturation of urban indoors may be suitable for the prevention of Th2-mediated allergies in childhood.
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Affiliation(s)
- Attila Bácsi
- Department of Immunology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (A.B.); (B.Á.); (K.P.)
| | - Beatrix Ágics
- Department of Immunology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (A.B.); (B.Á.); (K.P.)
- Doctoral School of Molecular Cell and Immune Biology, University of Debrecen, H-4032 Debrecen, Hungary
| | - Kitti Pázmándi
- Department of Immunology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary; (A.B.); (B.Á.); (K.P.)
| | - Béla Kocsis
- Department of Medical Microbiology and Immunology, Faculty of Medicine, University of Pécs, H-7624 Pécs, Hungary;
| | - Viktor Sándor
- Institute of Bioanalysis, Medical School and Szentágothai Research Center, University of Pécs, H-7624 Pécs, Hungary;
| | - Lóránd Bertók
- National Research Directorate for Radiobiology and Radiohygiene, National Public Health Center, H-1221 Budapest, Hungary
| | - Geza Bruckner
- Department of Athletic Training and Clinical Nutrition, University of Kentucky, Lexington, KY 40536, USA;
| | - Sándor Sipka
- Division of Clinical Immunology, Faculty of Medicine, University of Debrecen, H-4032 Debrecen, Hungary
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Antó JM, Pearce N, Douwes J, Garcia-Aymerich J, Pembrey L, Richiardi L, Sunyer J. Why has epidemiology not (yet) succeeded in identifying the origin of the asthma epidemic? Int J Epidemiol 2023; 52:974-983. [PMID: 37004248 PMCID: PMC10396414 DOI: 10.1093/ije/dyad035] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 03/15/2023] [Indexed: 04/04/2023] Open
Affiliation(s)
- Josep M Antó
- ISGlobal, Barcelona Institute for Global Health, Barcelona, Spain
- Hospital del Mar Medical Research Institute, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
| | - Neil Pearce
- Department of Non-communicable Disease Epidemiology and Medical Statistics, London School of Hygiene and Tropical Medicine, London, UK
| | - Jeroen Douwes
- Research Centre for Hauora and Health, Massey University, Wellington, New Zealand
| | - Judith Garcia-Aymerich
- ISGlobal, Barcelona Institute for Global Health, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
| | - Lucy Pembrey
- Department of Medical Statistics, London School of Hygiene and Tropical Medicine, London, UK
| | - Lorenzo Richiardi
- Cancer Epidemiology Unit, Department of Medical Sciences, University of Turin, and CPO-Piemonte, Torino, Italy
| | - Jordi Sunyer
- ISGlobal, Barcelona Institute for Global Health, Barcelona, Spain
- Hospital del Mar Medical Research Institute, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
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Aalberse RC, Hoekzema R, Grayson MH. Do germinal centers protect most of us from becoming allergic? Ann Allergy Asthma Immunol 2021; 127:301-305. [PMID: 34102303 DOI: 10.1016/j.anai.2021.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/20/2021] [Accepted: 06/01/2021] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To review the literature and discuss a hypothesis as to why most people do not have allergy. This hypothesis is dependent on the following 3 main components: (1) airborne allergens (eg, from pollen or mites) are weak antigens that induce a B-cell response only in immunologically most reactive subjects (ie, with atopy); (2) a roadblock to production of immunoglobulin E (IgE) is the T helper 2/interleukin 4 requirement for class switch to IgE; (3) activated germinal centers prevent the formation of mature IgE-switched B-cells, creating a second roadblock to IgE production. DATA SOURCES Transgenic reporter mice and a cross-sectional human cohort. STUDY SELECTIONS From the mouse studies, we selected the data on histology and tissue-derived cell suspensions published by several groups in 2011 to 2014. From the human cohort, we selected our published microarray data on the levels of allergen-specific IgE and IgG in serum. RESULTS The immune response to airborne atopic allergens entails both IgE and IgG antibodies rather than just an IgG or IgE response. However, as expected for an immune response without mature germinal centers, the specific IgG levels will be very low, typically in the ng/ml range. CONCLUSION Control of IgE production is not just through the T helper 2/interleukin 4-mediated class switch. Recent studies suggest that mature germinal centers are likely to provide protection against the development of allergy to airborne allergens, as well. This may explain why allergen exposure does not induce allergen-specific IgE in everyone.
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Affiliation(s)
- Rob C Aalberse
- Department of Immunopathology, Sanquin Research, Amsterdam, the Netherlands; Faculty of Science, University of Amsterdam, Amsterdam, the Netherlands.
| | - Rick Hoekzema
- Department of Dermatology, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | - Mitchell H Grayson
- Division of Allergy and Immunology, Department of Pediatrics, Nationwide Children's Hospital, The Ohio State University College of Medicine, Columbus, Ohio; Center for Clinical and Translational Research, the Abigail Wexner Research Institute, Nationwide Children's Hospital, Columbus, Ohio
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Steiman CA, Evans MD, Lee KE, Lasarev MR, Gangnon RE, Olson BF, Barnes KL, Bendixsen CG, Seroogy CM, Gern JE. Patterns of farm exposure are associated with reduced incidence of atopic dermatitis in early life. J Allergy Clin Immunol 2020; 146:1379-1386.e6. [PMID: 32650021 PMCID: PMC7721989 DOI: 10.1016/j.jaci.2020.06.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 06/14/2020] [Accepted: 06/22/2020] [Indexed: 02/04/2023]
Abstract
BACKGROUND Farm exposures may reduce the risk of atopic dermatitis (AD) in children, but this is controversial and US data are limited. OBJECTIVE This study was conducted to identify patterns of farm exposure in Wisconsin family farms that modify AD incidence and prevalence in early childhood. METHODS Environmental exposures, health history, and clinical outcomes were prospectively recorded for 111 farm families and 129 non-farm families enrolled in the Wisconsin Infant Study Cohort birth cohort study. Exposures from the prenatal and early postnatal (2-month) visits were evaluated together with parental report of AD diagnosis by a health care provider through age 24 months. Latent class analysis was performed with prenatal and early postnatal farm-exposure variables to assign farm children to 3 classes. RESULTS Overall, children of farm families had reduced AD incidence (P = .03). Within farm families, exposures including poultry (3% vs 28%; P = .003), pig (4% vs 25%; P = .04), feed grain (13% vs 34%; P = .02), and number of animal species were inversely associated with AD incidence. Among the latent class groups, children in families with diverse or more intense farm exposures (classes A and B) had reduced AD incidence, whereas low-exposure (class C) infants had AD incidence similar to that in nonfarm children. CONCLUSIONS Infants in Wisconsin farm families had reduced AD incidence, and patterns of farm exposures further defined AD risk. These findings suggest that exposure to diverse farm animals, feed, and bedding during the prenatal period and in early infancy reduce the risk of early-onset AD, a phenotype associated with multiple other atopic diseases.
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Affiliation(s)
- Cheryl A Steiman
- University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Michael D Evans
- University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Kristine E Lee
- University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Michael R Lasarev
- University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Ronald E Gangnon
- University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Brent F Olson
- Marshfield Clinic Research Institute, National Farm Medicine Center, Marshfield, Wis
| | - Kathrine L Barnes
- Marshfield Clinic Research Institute, National Farm Medicine Center, Marshfield, Wis
| | - Casper G Bendixsen
- Marshfield Clinic Research Institute, National Farm Medicine Center, Marshfield, Wis
| | | | - James E Gern
- University of Wisconsin School of Medicine and Public Health, Madison, Wis.
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6
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Corrigendum. Clin Exp Immunol 2019; 198:281. [DOI: 10.1111/cei.13364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Sánchez J, Sánchez A, Cardona R. Particular characteristics of atopic eczema in tropical environments. The Tropical Environment Control for Chronic Eczema and Molecular Assessment (TECCEMA) cohort study. An Bras Dermatol 2017; 92:177-183. [PMID: 28538875 PMCID: PMC5429101 DOI: 10.1590/abd1806-4841.20175140] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 02/11/2016] [Indexed: 01/13/2023] Open
Abstract
Background Atopic dermatitis is a prevalent health problem in the world. Allergic
sensitization is an important risk factor, but the roles of other factors,
inherent in tropic region, are unknown. Objective A cohort study was designed in a tropical city to investigate molecular and
environmental risk factors for eczema, considering as particular features
perennial exposure to mites, poor living conditions and others tropical
characteristics. Methods 433 patients were included at baseline and biological samples were collected
during 24 months of follow-up. Clinical information was collected using
questionnaires (SCORAD, DLQI and a subjective scale) during each clinical
assessment. Results The prevalence of atopic eczema was 93%, with similar frequency between
children and adults; parents history of eczema and polysensitization to
mites, dogs, cats, cockroaches and birds, were risk factors for severe and
persistent eczema and allergic comorbidities. Food sensitization was present
in 16% of patients but food-induced allergies were scarce. Psychiatric,
dental and ocular disorders were the most frequent non-allergic
comorbidities. Study limitations selection bias. Conclusion We presented a tropical cohort of patients with eczema and we identified some
risk factors for severe and persistent dermatitis. Some patterns of
sensitization were associated with severe eczema and respiratory symptoms,
and the natural history of "atopic march" is different to that described in
some industrialized countries. The collection of biological samples will
contribute to the understanding of the gene/environment interactions leading
to allergy inception and evolution.
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Affiliation(s)
- Jorge Sánchez
- Group of Clinical and Experimental Allergy, Pediatric and Allergy Department, University of Antioquia - Medellín, Colombia
| | - Andrés Sánchez
- Group of Clinical and Experimental Allergy, Pediatric and Allergy Department, University of Antioquia - Medellín, Colombia.,Medicine Department, Corporación Universitaria Rafael Nuñez - Cartagena, Colombia
| | - Ricardo Cardona
- Group of Clinical and Experimental Allergy, Pediatric and Allergy Department, University of Antioquia - Medellín, Colombia
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8
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Renz H, Holt PG, Inouye M, Logan AC, Prescott SL, Sly PD. An exposome perspective: Early-life events and immune development in a changing world. J Allergy Clin Immunol 2017; 140:24-40. [DOI: 10.1016/j.jaci.2017.05.015] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 05/22/2017] [Accepted: 05/23/2017] [Indexed: 02/09/2023]
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9
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Varyani F, Fleming JO, Maizels RM. Helminths in the gastrointestinal tract as modulators of immunity and pathology. Am J Physiol Gastrointest Liver Physiol 2017; 312:G537-G549. [PMID: 28302598 PMCID: PMC5495915 DOI: 10.1152/ajpgi.00024.2017] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 03/06/2017] [Accepted: 03/12/2017] [Indexed: 01/31/2023]
Abstract
Helminth parasites are highly prevalent in many low- and middle-income countries, in which inflammatory bowel disease and other immunopathologies are less frequent than in the developed world. Many of the most common helminths establish themselves in the gastrointestinal tract and can exert counter-inflammatory influences on the host immune system. For these reasons, interest has arisen as to how parasites may ameliorate intestinal inflammation and whether these organisms, or products they release, could offer future therapies for immune disorders. In this review, we discuss interactions between helminth parasites and the mucosal immune system, as well as the progress being made toward identifying mechanisms and molecular mediators through which it may be possible to attenuate pathology in the intestinal tract.
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Affiliation(s)
- Fumi Varyani
- 1Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom; ,2Edinburgh Clinical Academic Track, Western General Hospital, University of Edinburgh, Edinburgh, United Kingdom; and
| | - John O. Fleming
- 3Department of Neurology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Rick M. Maizels
- 1Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom;
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10
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Xiao M, Yang J, Feng Y, Zhu Y, Chai X, Wang Y. Metaproteomic strategies and applications for gut microbial research. Appl Microbiol Biotechnol 2017; 101:3077-3088. [PMID: 28293710 DOI: 10.1007/s00253-017-8215-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 02/28/2017] [Accepted: 03/04/2017] [Indexed: 01/16/2023]
Abstract
The human intestine hosts various complex microbial communities that are closely associated with multiple health and disease processes. Determining the composition and function of these microbial communities is critical to unveil disease mechanisms and promote human health. Recently, meta-omic strategies have been developed that use high-throughput techniques to provide a wealth of information, thus accelerating the study of gut microbes. Metaproteomics is a newly emerged analytical approach that aims to identify proteins on a large scale in complex environmental microbial communities (e.g., the gut microbiota). This review introduces the recent analytical strategies and applications of metaproteomics, with a focus on advances in gut microbiota research, including a discussion of the limitations and challenges of these approaches.
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Affiliation(s)
- Mingming Xiao
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China.,Research and Development Center of Traditional Chinese Medicine, Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin, 300457, China
| | - Junjun Yang
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China.,Research and Development Center of Traditional Chinese Medicine, Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin, 300457, China
| | - Yuxin Feng
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China.,Research and Development Center of Traditional Chinese Medicine, Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin, 300457, China
| | - Yan Zhu
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China.,Research and Development Center of Traditional Chinese Medicine, Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin, 300457, China
| | - Xin Chai
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China.,Research and Development Center of Traditional Chinese Medicine, Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin, 300457, China
| | - Yuefei Wang
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China. .,Research and Development Center of Traditional Chinese Medicine, Tianjin International Joint Academy of Biotechnology and Medicine, Tianjin, 300457, China.
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Guidry VT, Kinlaw AC, Johnston J, Hall D, Wing S. Hydrogen sulfide concentrations at three middle schools near industrial livestock facilities. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2017; 27:167-174. [PMID: 27094997 DOI: 10.1038/jes.2016.7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Revised: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 06/05/2023]
Abstract
Safe school environments are essential for healthy development, yet some schools are near large-scale livestock facilities that emit air pollution. Hydrogen sulfide (H2S) from decomposing manure is an indicator of livestock-related air pollution. We measured outdoor concentrations of H2S at three public middle schools near livestock facilities in North Carolina. We used circular graphs to relate H2S detection and wind direction to geospatial distributions of nearby livestock barns. We also used logistic and linear regression to model H2S in relation to upwind, distance-weighted livestock barn area. Circular graphs suggested an association between upwind livestock barns and H2S detection. The log-odds of H2S detection per 1000 m2 increased with upwind weighted swine barn area (School A: β-coefficient (β)=0.43, SE=0.06; School B: β=0.64, SE=0.24) and upwind weighted poultry barn area (School A: β=0.05, SE=0.01), with stronger associations during periods of atmospheric stability than atmospheric instability (School A stable: β=0.69, SE=0.11; School A unstable: β=0.32, SE=0.09). H2S concentration also increased linearly with upwind swine barn area, with greater increases during stable atmospheric conditions (stable: β=0.16 parts per billion (p.p.b.), SE=0.01; unstable: β=0.05 p.p.b., SE=0.01). Off-site migration of pollutants from industrial livestock operations can decrease air quality at nearby schools.
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Affiliation(s)
- Virginia T Guidry
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Alan C Kinlaw
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jill Johnston
- Division of Environmental Health, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Devon Hall
- Rural Empowerment Association for Community Help, Warsaw, North Carolina, USA
| | - Steve Wing
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Freitas MS, de Córdoba Lanza F, Monteiro JCS, Solé D. Prevalence of rhinitis and associated factors in schoolchildren who live in the Amazon islands. Am J Rhinol Allergy 2017; 30:79-82. [PMID: 27216340 DOI: 10.2500/ajra.2016.30.4293] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND The prevalence of rhinitis has been reported to be higher in urban areas. OBJECTIVE To determine the prevalence of rhinitis in schoolchildren who lived on two islands in the Brazilian Amazon, including a rural island and an urban island, and to identify the associated risk factors. METHODS Four hundred children (200 per island) were evaluated by using the International Study of Asthma and Allergy in Childhood standard written questionnaire (rhinitis module). A convenience sample for both islands was selected based on the age group of the study (5-8 years). The children were assessed for potential risk factors (complementary written questionnaire) identified by logistic regression. RESULTS The prevalence of active rhinitis was significantly higher in the children who lived on Outeiro Island compared with Combú Island (34.5% versus 18.0%, respectively). The associated risk factors for rhinitis symptoms on Combú Island included parental history of rhinitis (odds ratio [OR] 9.4 [95% confidence interval {CI}, 2.1-41.4]) and delivery by caesarean-section (OR 5.2 [95% CI, 1.2-21.9]), and for Outeiro Island included parental history of rhinitis (OR 4.5 [95% CI, 1.7-11.2]) and of asthma (OR 3.8 [95% CI, 1.5-9.8]), nocturnal cough in the previous year (OR 5.8 [95% CI, 2.1-16.0]), breast-feeding (≥6 months) (OR 9.6 [95% CI, 1.1-82.1]), moisture (OR 2.4 [95% CI, 0.9-6.4]), and consumption of fruit juice more than two times a week (OR 4.3 [95% CI, 1.2-15.0]). CONCLUSION The different risk factors identified for rhinitis on each island indicated the role of the urban environment in the development of the disease.
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Allergen-Associated Immunomodulators: Modifying Allergy Outcome. Arch Immunol Ther Exp (Warsz) 2016; 64:339-47. [PMID: 27178664 DOI: 10.1007/s00005-016-0401-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 02/21/2016] [Indexed: 12/22/2022]
Abstract
The prevalence of allergies is increasing since mid twentieth century; however the underlying causes of this increase are not fully clear. Understanding the mechanism by which a harmless protein becomes an allergen provides us with the basis to prevent and treat these diseases. Although most studies on allergen immunogenicity have traditionally focused on structural properties of the proteins, it is increasingly clear that allergenicity cannot be determined only based on structural features of the allergenic proteins. In fact, allergens do not encounter human facings as isolated molecules but contained in complex mixtures of proteins, carbohydrates and lipids, such as pollen grains or foods. As a result, attention has lately been directed to examine whether allergen-associated molecules exhibit immune-regulatory properties. The present review aims to illustrate some examples of how non-protein molecules accompanying the allergen can modulate allergic responses.
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14
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Wagner A, Schabussova I, Drinic M, Akgün J, Loupal G, Kundi M, Joachim A, Wiedermann U. Oocyst-Derived Extract of Toxoplasma Gondii Serves as Potent Immunomodulator in a Mouse Model of Birch Pollen Allergy. PLoS One 2016; 11:e0155081. [PMID: 27149118 PMCID: PMC4857930 DOI: 10.1371/journal.pone.0155081] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/24/2016] [Indexed: 12/22/2022] Open
Abstract
Introduction Previously, we have shown that oral infection with Toxoplasma gondii oocysts prevented type I allergy in mice. Here we investigated whether the application of a T. gondii oocyst lysate antigen (OLA) could also reduce allergy development. BALB/c mice were immunised twice with OLA followed by sensitisation with the major birch pollen (BP) allergen Bet v 1 and an aerosol challenge with BP extract. Methods First, we tested OLA in vitro. Stimulation of splenocytes and bone marrow-derived dendritic cells (BMDC) with OLA led to the production of pro-inflammatory and regulatory cytokines such as IL-6, IFN-γ and IL-10. Moreover, BMDC exposed to OLA upregulated the maturation markers CD40, CD80, CD86, and MHCII. Furthermore, OLA was recognised by TLR2-transfected human embryonic kidney cells. Results Immunisation of mice with OLA induced high levels of Toxoplasma-specific IgG antibodies in sera along with increased production of IFN-γ and IL-10 in Toxoplasma-antigen restimulated splenocytes. OLA reduced allergic airway inflammation as manifested by significant reduction of eosinophils in bronchoalveolar fluids, decreased cellular infiltrates and mucus production in the lungs. Accordingly, Bet v 1-specific IgE was decreased in OLA-pretreated mice. The reduced allergic immune responses were accompanied by increased numbers of CD4+CD25highFoxp3+ regulatory T cells in spleens as well as by increased numbers of granulocytic myeloid-derived suppressor cells in lungs when compared to sensitised controls suggesting that these two cell populations might be involved in the suppression of the allergic immune responses. Conclusion Our data demonstrate that pretreatment with the oocyst extract can exert anti-allergic effects comparable to T. gondii infection. Thus, the immunomodulatory properties of the parasite extract indicate that this extract and in the future defined molecules thereof might serve as immunomodulatory adjuvants in allergy treatment and prophylaxis.
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Affiliation(s)
- Angelika Wagner
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology & Immunology, Medical University of Vienna, Vienna, Austria
| | - Irma Schabussova
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology & Immunology, Medical University of Vienna, Vienna, Austria
| | - Mirjana Drinic
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology & Immunology, Medical University of Vienna, Vienna, Austria
| | - Johnnie Akgün
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology & Immunology, Medical University of Vienna, Vienna, Austria
| | - Gerhard Loupal
- Institute of Pathology and Forensic Veterinary Medicine, Department of Pathobiology, University of Veterinary Medicine, Vienna, Austria
| | - Michael Kundi
- Institute of Environmental Health, Center for Public Health, Medical University of Vienna, Vienna, Austria
| | - Anja Joachim
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine, Vienna, Austria
| | - Ursula Wiedermann
- Institute of Specific Prophylaxis and Tropical Medicine, Center for Pathophysiology, Infectiology & Immunology, Medical University of Vienna, Vienna, Austria
- * E-mail:
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15
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Abstract
The gastrointestinal (GI) tract microbiota is required for optimal digestion of foods, for the development of resistance against pathogens (termed colonization resistance), for the development of mucosa-associated lymphoid tissue, and for local as well as systemic immune homeostasis. Certain constituents of the GI tract microbiota are widely recognized as critical regulators and modulators of their host's immune response. These include bacterial members of the microbiota as well as parasitic nematodes. Immune regulation by immunomodulatory members of the GI microbiota primarily serves to subvert host antimicrobial immune defenses and promote persistent colonization, but as a side effect may prevent or suppress immunological disorders resulting from inappropriate responses to harmless antigens, such as allergy, colitis or autoimmunity. Many of the best understood GI-resident immunomodulatory species have co-evolved with their mammalian hosts for tens of thousands of years and masterfully manipulate host immune responses. In this review, we discuss the epidemiological evidence for the role of the GI tract microbiota as a whole, and of specific members, in protection against allergic and other immunological disorders. We then focus on the mechanistic basis of microbial immunomodulation, which is presented using several well-understood paradigmatic examples, that is, helminths, Helicobacter pylori, Bifidobacteria and Lactobacilli. In a final chapter, we highlight past and ongoing attempts at harnessing the immunomodulatory properties of GI microbiota species and their secreted products for intervention studies and describe the promises and limitations of these experimental approaches. The effects of pro- and prebiotics, bacterial lysates, as well as of fecal microbiota transplantation are presented and compared.
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Affiliation(s)
- Andreas Kyburz
- Institute of Molecular Cancer Research, University of Zurich, Winterthurerstr, Zurich, Switzerland
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16
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Gern JE. Promising candidates for allergy prevention. J Allergy Clin Immunol 2015; 136:23-8. [PMID: 26145984 DOI: 10.1016/j.jaci.2015.05.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 05/21/2015] [Accepted: 05/21/2015] [Indexed: 12/16/2022]
Abstract
Recent advances in understanding environmental risk factors for allergic diseases in children have led to renewed efforts aimed at prevention. Factors that modify the probability of developing allergies include prenatal exposures, mode of delivery, diet, patterns of medication use, and exposure to pets and farm animals. Recent advances in microbial detection techniques demonstrate that exposure to diverse microbial communities in early life is associated with a reduction in allergic disease. In fact, microbes and their metabolic products might be essential for normal immune development. Identification of these risk factors has provided new targets for prevention of allergic diseases, and possibilities of altering microbial exposure and colonization to reduce the incidence of allergies is a promising approach. This review examines the rationale, feasibility, and potential effect for the prevention of childhood allergic diseases and explores possible strategies for enhancing exposure to beneficial microbes.
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Affiliation(s)
- James E Gern
- Departments of Pediatrics and Medicine, University of Wisconsin-Madison, Madison, Wis.
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17
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Cooper PJ, Chico ME, Amorim LD, Sandoval C, Vaca M, Strina A, Campos AC, Rodrigues LC, Barreto ML, Strachan DP. Effects of maternal geohelminth infections on allergy in early childhood. J Allergy Clin Immunol 2015; 137:899-906.e2. [PMID: 26395817 PMCID: PMC4774946 DOI: 10.1016/j.jaci.2015.07.044] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 07/09/2015] [Accepted: 07/14/2015] [Indexed: 01/15/2023]
Abstract
Background Maternal geohelminth infections during pregnancy may protect against allergy development in childhood. Objective We sought to investigate the effect of maternal geohelminths on the development of eczema, wheeze, and atopy during the first 3 years of life. Methods A cohort of 2404 neonates was followed to 3 years of age in a rural district in coastal Ecuador. Data on wheeze and eczema were collected by means of questionnaire and physical examination at 13, 24, and 36 months of age. Atopy was measured based on skin prick test (SPT) reactivity to 9 allergens at 36 months. Maternal stool samples were examined for geohelminths by microscopy. Data on potential confounders was collected after birth by questionnaire. Results Geohelminths were observed in 45.9% of mothers. Eczema and wheeze were reported for 17.7% and 25.9%, respectively, of 2069 (86.1%) children with complete follow-up to 3 years, and allergen SPT reactivity to any allergen was present in 17.2% and to house dust mite in 8.7%. Maternal geohelminth infections were not significantly associated with eczema (adjusted odds ratio [OR], 1.26; 95% CI, 0.98-1.61), wheeze (adjusted OR, 1.02; 95% CI, 0.82-1.27), and SPT reactivity to any allergen (adjusted OR, 0.79; 95% CI, 0.61-1.01). In subgroup analyses maternal geohelminths were associated with a significantly reduced risk of SPT reactivity to mite and other perennial allergens, and maternal ascariasis was associated with an increased risk of eczema and reduced risk of SPT reactivity to all allergens. Conclusion Our data do not support a protective effect of maternal infections with geohelminth parasites during pregnancy against the development of eczema and wheeze in early childhood, although there was evidence in subgroup analyses for a reduction in SPT reactivity to house dust mites and perennial allergens.
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Affiliation(s)
- Philip J Cooper
- Laboratorio de Investigaciones FEPIS, Avenida Via Guayllabamba, Quininde, Ecuador; Centro de Investigacion en Enfermedades Infecciosas, Pontificia Universidad Catolica del Ecuador, Quito, Ecuador; Institute of Infection and Immunity, St George's University of London, London, United Kingdom.
| | - Martha E Chico
- Laboratorio de Investigaciones FEPIS, Avenida Via Guayllabamba, Quininde, Ecuador
| | - Leila D Amorim
- Instituto de Saude Coletiva, Universidade Federal da Bahia, Rua Basilio de Gama, Salvador, Brazil
| | - Carlos Sandoval
- Laboratorio de Investigaciones FEPIS, Avenida Via Guayllabamba, Quininde, Ecuador
| | - Maritza Vaca
- Laboratorio de Investigaciones FEPIS, Avenida Via Guayllabamba, Quininde, Ecuador
| | - Agostino Strina
- Instituto de Saude Coletiva, Universidade Federal da Bahia, Rua Basilio de Gama, Salvador, Brazil
| | - Ana Clara Campos
- Instituto de Saude Coletiva, Universidade Federal da Bahia, Rua Basilio de Gama, Salvador, Brazil
| | - Laura C Rodrigues
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Mauricio L Barreto
- Instituto de Saude Coletiva, Universidade Federal da Bahia, Rua Basilio de Gama, Salvador, Brazil
| | - David P Strachan
- Institute of Public Health Sciences, St George's University of London, London, United Kingdom
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18
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Luna MDFGD, Fisher GB, Luna JRGD, Silva MGCD, Almeida PCD, Chiesa D. Prevalence of rhinitis among 6 and 7-year old students in Fortaleza. Rev Assoc Med Bras (1992) 2015; 60:357-64. [PMID: 25211420 DOI: 10.1590/1806-9282.60.04.0015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 01/13/2014] [Indexed: 01/02/2023] Open
Abstract
OBJECTIVE to evaluate the prevalence of rhinitis symptoms among 6 and 7-year old schoolchildren in Fortaleza, Brazil. METHODS a cross-sectional study using the rhinitis module of the ISAAC (International Study of Asthma and Allergies in Childhood) questionnaire. The sample included 2,020 students from public and private schools, in 2010. RESULTS the prevalence of cumulative rhinitis, active rhinitis, allergic rhinoconjunctivitis and physician-diagnosed rhinitis was 49.9%, 42%, 15.4% and 28.1%, respectively, being significantly more prevalent among private school students (OR = 0.55, 95CI: 0.46 - 0.66, p < 0.001; OR = 0.50, 95CI: 0.41 - 0.60, p < 0.001; OR = 0.67, 95CI: 0.52 - 0.85, p < 0.001; OR = 0.15, 95CI: 0.12 - 0.19, p < 0.001, respectively), without differences between genders. Interference with daily activities was reported by 25.3%, while 5.7% reported to be moderately or severely affected, without a difference between genders. CONCLUSION the prevalence of rhinitis symptoms and associated morbidity among 6-7-year old schoolchildren in Fortaleza was above the Brazilian average, with predominance among private school students, without difference between genders. It was observed that rhinitis was underdiagnosed in this population.
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Affiliation(s)
| | - Gilberto B Fisher
- Post-Graduate in Pediatric Medicine course, UFRGS, Porto Alegre, RS, Brazil
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19
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Zaph C, Cooper PJ, Harris NL. Mucosal immune responses following intestinal nematode infection. Parasite Immunol 2014; 36:439-52. [PMID: 25201407 PMCID: PMC4312905 DOI: 10.1111/pim.12090] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 11/05/2013] [Indexed: 12/12/2022]
Abstract
In most natural environments, the large majority of mammals harbour parasitic helminths that often live as adults within the intestine for prolonged periods (1-2 years). Although these organisms have been eradicated to a large extent within westernized human populations, those living within rural areas of developing countries continue to suffer from high infection rates. Indeed, recent estimates indicate that approximately 2.5 billion people worldwide, mainly children, currently suffer from infection with intestinal helminths (also known as geohelminths and soil-transmitted helminths) . Paradoxically, the eradication of helminths is thought to contribute to the increased incidence of autoimmune diseases and allergy observed in developed countries. In this review, we will summarize our current understanding of host-helminth interactions at the mucosal surface that result in parasite expulsion or permit the establishment of chronic infections with luminal dwelling adult worms. We will also provide insight into the adaptive immune mechanisms that provide immune protection against re-infection with helminth larvae, a process that is likely to be key to the future development of successful vaccination strategies. Lastly, the contribution of helminths to immune modulation and particularly to the treatment of allergy and inflammatory bowel disease will be discussed.
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Affiliation(s)
- C Zaph
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
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20
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Chu LM, Rennie DC, Cockcroft DW, Pahwa P, Dosman J, Hagel L, Karunanayake C, Pickett W, Lawson JA. Prevalence and determinants of atopy and allergic diseases among school-age children in rural Saskatchewan, Canada. Ann Allergy Asthma Immunol 2014; 113:430-9. [PMID: 25129487 DOI: 10.1016/j.anai.2014.07.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Revised: 06/27/2014] [Accepted: 07/07/2014] [Indexed: 12/27/2022]
Abstract
BACKGROUND There have been few investigations of farming-related activities or specific characteristics resulting in the associations between those exposures and atopic disease. OBJECTIVE To study the associations between farm-associated exposures and atopic diseases. METHODS As part of a longitudinal study of lung health in rural residents, a cross-sectional baseline study was conducted in rural Saskatchewan, Canada. This included an initial survey phase followed by a clinical testing phase. A subsample of 584 children (grades 1-8) completed skin prick testing to assess atopic status. Atopy was defined as a positive reaction to any of 6 allergens (local grasses, wheat dust, cat dander, house dust mite, Alternaria species, or Cladosporium species) of at least 3 mm compared with the negative control. RESULTS Of those who completed clinical testing, the prevalence of atopy was 19.4%, that of hay fever was 8.8%, and that of eczema was 27.4%. Based on skin prick testing, sensitization was highest for cat dander (8.6%) followed by local grasses (8.2%) and house dust mite (5.1%). After adjustment for potential confounders, home location (farm vs non-farm) was not associated with atopic status. However, livestock farming was protective against atopy (adjusted odds ratio 0.38, 95% confidence interval 0.17-0.88). In contrast, current residence on a farm was associated with an increase in the likelihood of hay fever in these children (adjusted odds ratio 3.68, 95% confidence interval 1.29-10.45). Also, regular farming activities in the past year were associated with an increased risk of hay fever. CONCLUSION In children, livestock exposure has a protective effect on skin prick test positivity, whereas farm living and activities increase the risk of hay fever.
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Affiliation(s)
- Luan M Chu
- Department of Community Health and Epidemiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Donna C Rennie
- Canadian Center for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Donald W Cockcroft
- Department of Medicine, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - P Pahwa
- Department of Community Health and Epidemiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Canadian Center for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - J Dosman
- Canadian Center for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - L Hagel
- Canadian Center for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - C Karunanayake
- Canadian Center for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - William Pickett
- Department of Public Health Sciences, Queen's University, Kingston, Ontario, Canada
| | - Joshua A Lawson
- Canadian Center for Health and Safety in Agriculture, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
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21
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Wells AD, Poole JA, Romberger DJ. Influence of farming exposure on the development of asthma and asthma-like symptoms. Int Immunopharmacol 2014; 23:356-63. [PMID: 25086344 DOI: 10.1016/j.intimp.2014.07.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/09/2014] [Accepted: 07/11/2014] [Indexed: 12/24/2022]
Abstract
Based upon age and type of farming exposures, a wide range of studies demonstrate either protective or deleterious effects of the farming environment on asthma. In this review, we highlight key studies supporting the concept that farming exposure protects children from asthma and atopy based on studies performed largely in European pediatric cohorts. Various types of farming in certain regions appear to have a greater effect on asthma protection, as does the consumption of unpasteurized milk. In the United State, where concentrated animal feeding operations (CAFOs) are more common, asthma is increased in children exposed especially to swine CAFOs; whereas, rates of atopy and allergy are lower in these children. We also review studies evaluating the role of farming exposures both as a child and/or as an adult on asthma seen in adults. The importance of microbes in farming environments and the contribution of various components of the innate immune system including toll-like receptors to the underlying mechanisms of asthma related to farming exposures are also reviewed.
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Affiliation(s)
- Adam D Wells
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5990, USA
| | - Jill A Poole
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5990, USA
| | - Debra J Romberger
- VA Nebraska-Western Iowa Health Care System, Research Service, Omaha, NE 68105, USA; Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5990, USA
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22
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Cooper PJ, Chico ME, Platts-Mills TA, Rodrigues LC, Strachan DP, Barreto ML. Cohort Profile: The Ecuador Life (ECUAVIDA) study in Esmeraldas Province, Ecuador. Int J Epidemiol 2014; 44:1517-27. [PMID: 24990475 PMCID: PMC4681103 DOI: 10.1093/ije/dyu128] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2014] [Indexed: 12/11/2022] Open
Abstract
The ECUAVIDA birth cohort is studying the impact of exposures to soil-transmitted helminth (STH) parasites and early-life microbial exposures on the development of atopy, allergic diseases and immune responses in childhood. A total of 2404 newborns were recruited between 2006 and 2009 in a public hospital serving the rural district of Quininde, Esmeraldas Province, in a tropical region of coastal Ecuador. Detailed measurements were done around the time of the birth, at 7 and 13 months and at 2 and 3 years, and data collection is ongoing at 5 and 8 years. Data being collected include questionnaires for: sociodemographic, lifestyle, psychosocial (at 4-6 years only) and dietary (at 6-7 years only) factors; childhood morbidity and clinical outcomes; stool samples for parasites; blood samples for DNA, measurements of vaccine responses and other measures of immune function/inflammation; and anthropometrics. Allergen skin prick test reactivity is done from 2 years and measures of airway function and inflammation at 8 years.
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Affiliation(s)
- Philip J Cooper
- Laboratorio de Investigaciones FEPIS, Quinindé, Esmeraldas Province, Ecuador, Institute of Infection and Immunity Research, Institute of Population Health Research, St George's University of London, London, UK, Centro de Investigación en Enfermedades Infecciosas, Escuela de Biología, Pontificia Universidad Católica del Ecuador, Quito, Ecuador,
| | - Martha E Chico
- Laboratorio de Investigaciones FEPIS, Quinindé, Esmeraldas Province, Ecuador
| | - Thomas Ae Platts-Mills
- Division of Allergy and Clinical Immunology, University of Virginia Health System, Charlottesville, VA, USA
| | - Laura C Rodrigues
- Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, UK and
| | - David P Strachan
- Institute of Population Health Research, St George's University of London, London, UK
| | - Mauricio L Barreto
- Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, Brazil
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Cooper PJ, Vaca M, Rodriguez A, Chico ME, Santos DN, Rodrigues LC, Barreto ML. Hygiene, atopy and wheeze-eczema-rhinitis symptoms in schoolchildren from urban and rural Ecuador. Thorax 2014; 69:232-9. [PMID: 24105783 PMCID: PMC3932750 DOI: 10.1136/thoraxjnl-2013-203818] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 08/20/2013] [Accepted: 09/16/2013] [Indexed: 11/24/2022]
Abstract
BACKGROUND Rural residence is protective against atopy and wheeze-rhinitis-eczema symptoms in developed countries, an effect attributed to farming and poor hygiene exposures. There are few data from developing countries addressing this question. We compared atopy and wheeze-rhinitis-eczema symptoms between urban and rural Ecuador, and explored the effects of farming and poor hygiene exposures. METHODS We performed cross sectional studies of schoolchildren living in rural and urban Ecuador. Data on symptoms and farming/hygiene exposures were collected by parental questionnaire, atopy by allergen skin prick test reactivity and geohelminth infections by stool examinations. RESULTS Among 2526 urban and 4295 rural schoolchildren, prevalence was: atopy (10.0% vs 12.5%, p=0.06), wheeze (9.4% vs 10.1%, p=0.05), rhinitis (8.1% vs 6.4%, p=0.02) and eczema (5.9% vs 4.7%, p=0.06). A small proportion of symptoms were attributable to atopy (range 3.9-10.7%) with greater attributable fractions for respiratory symptoms observed in urban schoolchildren. Respiratory symptoms were associated with poor hygiene/farming exposures: wheeze with lack of access to potable water; and rhinitis with household pets, no bathroom facilities and contact with large farm animals. Birth order was inversely associated with respiratory symptoms. Area of residence and atopy had few effects on these associations. CONCLUSIONS Urban schoolchildren living in Ecuador have a similar prevalence of atopy, eczema and wheeze but a higher prevalence of rhinitis compared with rural children. Some farming and poor hygiene exposures were associated with an increase in the prevalence of wheeze or rhinitis while birth order was inversely associated with these symptoms.
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Affiliation(s)
- Philip J Cooper
- Laboratorio de Investigaciones FEPIS, Quinindé, Esmeraldas Province, Ecuador
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24
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Deng Y, Li W, Luo Y, Wang LJ, Xie XH, Luo J, Luo ZX, Zhao XD, Fu Z, Liu EM. Inhibition of IFN-γ promotes anti-asthma effect of Mycobacterium bovis Bacillus Calmette-Guerin neonatal vaccination: a murine asthma model. Vaccine 2014; 32:2070-8. [PMID: 24560675 DOI: 10.1016/j.vaccine.2014.02.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Revised: 02/01/2014] [Accepted: 02/06/2014] [Indexed: 11/29/2022]
Abstract
OBJECTIVE The Mycobacterium bovis Bacillus Calmette-Guerin (BCG) neonatal vaccination inhibits allergy-induced pathologic changes. However, the mechanisms underlying this process are unclear. This study aimed to investigate the role of interferon (IFN)-γ and interleukin (IL)-17 in the protective effects of the BCG neonatal vaccination on allergic pulmonary inflammation and airway hyperresponsiveness (AHR). METHODS Wild type (WT)-neonate and IL-17 knock out (KO) neonate mice were vaccinated with BCG. A murine asthma model was developed by sensitization and then challenging with ovalbumin (OVA). Recombinant IL-17 or recombinant IFN-γ was delivered to the airway to overexpress IL-17 or IFN-γ. An anti-IFN-γ neutralizing antibody was used to block the effects of IFN-γ. RESULTS We found exogenous IL-17 delivered to the airway reversed the anti-asthma effects of the neonatal BCG vaccination. BCG neonatal vaccination further reduced OVA-induced inflammation and AHR in IL-17 KO mice. Inhibition of IFN-γ in BCG neonatal vaccinated OVA-induced asthma model mice led to a further reduction in airway inflammation and AHR. In addition, airway inflammation and AHR were robust following treatment with exogenous IFN-γ. Neutralizing IL-17 was not sufficient to block OVA-induced airway inflammation and AHR. In IL-17 KO mice, airway inflammation and AHR did not occur following treatment with an anti-IFN-γ neutralizing antibody. CONCLUSIONS In an OVA-induced murine asthma model, inhibition of IFN-γ enhanced the anti-asthma effects of BCG neonatal vaccination.
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Affiliation(s)
- Yu Deng
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing 400014, PR China
| | - Wei Li
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing 400014, PR China
| | - Yan Luo
- Department of Neonatology, The Affiliated Hospital of Zunyi Medical College, Zunyi 563003, PR China
| | - Li J Wang
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Medical University, Chongqing 400014, PR China
| | - Xiao H Xie
- Key Laboratory of Pediatrics in Chongqing, Chongqing Medical University, Chongqing 400014, PR China
| | - Jian Luo
- Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing Medical University, Chongqing 400014, PR China
| | - Zheng X Luo
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing 400014, PR China
| | - Xiao D Zhao
- Department of Nephrology and Immunology Medicine, Children's Hospital, Chongqing Medical University, Chongqing 400014, PR China
| | - Zhou Fu
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing 400014, PR China
| | - En M Liu
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing 400014, PR China.
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Asthma and Microbes: A New Paradigm. THE ROLE OF MICROBES IN COMMON NON-INFECTIOUS DISEASES 2014. [PMCID: PMC7120979 DOI: 10.1007/978-1-4939-1670-2_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Asthma is worldwide at pandemic levels for the past 30 years but is increasing at a greater rate in more affluent societies. It is a heterogeneous disorder caused by interaction between genetic predisposition, atopy, and environmental factors, including allergens, air pollution, and respiratory infections. The pathological aspects and pathophysiological mechanisms are reviewed in this chapter. Allergens or infectious agents may stimulate Th-2 inflammation which causes activation of IL-13, eosinophils, and increase IgE levels, subsequently leading to bronchial smooth muscle hypercontraction. Respiratory viral infections are well-known causes of precipitation of acute asthma exacerbations in 50–60 % of attacks. There is also increasing evidence that bacterial infections, Chlamydia pneumoniae, and Mycoplasma pneumoniae, may contribute to the onset and course of asthma. The two main hypothesis of microbial genesis of asthma that has arisen in the past 20–30 years appears to be incongruous, but are not, are the hygiene hypothesis of asthma, and the virus-related asthma, early onset of viral bronchiolitis in the susceptible hosts being responsible for later development of asthma. The clinical and experimental evidences to support these contentions are reviewed and critiqued.
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Sozańska B, Błaszczyk M, Pearce N, Cullinan P. Atopy and allergic respiratory disease in rural Poland before and after accession to the European Union. J Allergy Clin Immunol 2013; 133:1347-53. [PMID: 24342546 DOI: 10.1016/j.jaci.2013.10.035] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Revised: 10/17/2013] [Accepted: 10/24/2013] [Indexed: 10/25/2022]
Abstract
BACKGROUND In 2003, we recorded a striking difference in the prevalence of atopy between village and small-town populations in southwest Poland. Nine years later, we undertook a second survey of the same area. OBJECTIVE We sought to assess whether rapid changes in farming practices, driven by accession to the European Union in 2004, were accompanied by an increase in atopy, asthma, and hay fever in these villages. METHODS In 2012, we surveyed 1730 inhabitants older than 5 years (response rate, 85%); 560 villagers and 348 town inhabitants who had taken part in the earlier survey. Participants completed a questionnaire on farm-related exposures and symptoms of asthma and hay fever. Atopy was assessed by using skin prick tests. RESULTS In 2012, far fewer villagers had contact with cows (4% vs 24.3% in 2003) or pigs (14% vs 33.5%), milked cows (2.7% vs 12.7%), or drank unpasteurized milk (9% vs 35%). Among the villagers, there was a significant increase at all ages in the prevalence of atopy between 2003 and 2012 both in the total population (7.3% vs 19.6%, P < .0001) and among those who took part in both surveys (7.9% vs 17.8%, P < .0001). Among the townspeople, the prevalence of atopy did not change substantially (20% vs 19.9% and 21.7% vs 18.5%, respectively). Hay fever increased 2-fold in the villages (3.0% vs 7.7%) but not in the town (7.1% vs 7.2%); there was little or no change in asthma prevalence in the villages (5.0% vs 4.3%) or town (4.3% vs 5.0%). CONCLUSIONS We report a substantial increase in atopy at all ages and in a remarkably short period of time in a Polish population whose farm-related exposures were dramatically reduced after their country's accession to the European Union.
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Affiliation(s)
- Barbara Sozańska
- 1st Department of Pediatrics, Allergology and Cardiology, Wrocław Medical University, Wrocław, Poland
| | | | - Neil Pearce
- London School of Hygiene and Tropical Medicine, London, United Kingdom; Massey University, Wellington, New Zealand
| | - Paul Cullinan
- Imperial College (NHLI) and Royal Brompton Hospital, London, United Kingdom.
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The management of paediatric allergy: not everybody's cup of tea--10-11th February 2012. Curr Opin Allergy Clin Immunol 2013; 13 Suppl 1:S1-50. [PMID: 23377496 DOI: 10.1097/aci.0b013e32835e8b94] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Gourbeyre P, Desbuards N, Grémy G, Tranquet O, Champ M, Denery-Papini S, Bodinier M. Perinatal and postweaning exposure to galactooligosaccharides/inulin prebiotics induced biomarkers linked to tolerance mechanism in a mouse model of strong allergic sensitization. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:6311-6320. [PMID: 23746232 DOI: 10.1021/jf305315g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Food allergies are increasing, and no treatment exists, thus enhancing interest in prebiotic strategies. This study aimed to analyze the preventive effects of prebiotic feeding during perinatal and postweaning periods in a mouse model of allergy by studying biomarkers related to tolerance (IgG2a, IgA, IFN-γ, TGF-β, and IL-10), to allergy (IgE, IgG1, IL-4, IL-17, symptoms), and to microbiota (propionate and MyD88). Balb/c mice, both dams and their pups, were fed a diet supplemented with (+Prb) or without (-Prb) GOS/inulin prebiotics. Mice were then sensitized with allergens. Regardless of diet, sensitized mice exhibited similar levels of IgE, IgG1, CD-23, IL-4, IL-17, and symptoms. However, in comparison to -Prb-sensitized mice, +Prb-sensitized mice displayed higher concentrations of total IgG2a (6669 ± 1788 vs 3696 ± 1326 fluorescence units, p < 0.005), specific IgA (285 ± 26 vs 156 ± 9 fluorescence units, p < 0.01), IFN-γ (3194 ± 424 vs 1853 ± 434 pg/mL, p < 0.01), IL-10 (777 ± 87 vs 95 ± 136 pg/mL, p < 0.005), TGF-β (4853 ± 1959 vs 243 ± 444 pg/mL, p < 0.01), MyD88 (0.033 ± 0.019 vs 0.009 ± 0.004 relative expression, p < 0.01), and propionate (4.15 ± 0.8 vs 2.9 ± 1.15 μmol, p < 0.05). In a mouse model of allergy, prebiotic exposure during perinatal and postweaning periods induced the highest expression of biomarkers related to tolerance without affecting biomarkers related to allergy.
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Affiliation(s)
- Pascal Gourbeyre
- INRA, UR 1268 BIA, équipe Allergie, rue de la Géraudière, B.P. 71627, F-44316 Nantes Cedex 03, France
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Microbial influence on tolerance and opportunities for intervention with prebiotics/probiotics and bacterial lysates. J Allergy Clin Immunol 2013; 131:1453-63; quiz 1464. [DOI: 10.1016/j.jaci.2013.03.020] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 02/19/2013] [Accepted: 03/22/2013] [Indexed: 01/21/2023]
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Childhood asthma and allergies in urban, semiurban, and rural residential sectors in Chile. ScientificWorldJournal 2013; 2013:937935. [PMID: 23766726 PMCID: PMC3676905 DOI: 10.1155/2013/937935] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 04/15/2013] [Indexed: 12/29/2022] Open
Abstract
While rural living protects from asthma and allergies in many countries, results are conflicting in Latin America. We studied the prevalence of asthma and asthma symptoms in children from urban, semiurban, and rural sectors in south Chile. A cross-sectional questionnaire study was conducted in semiurban and rural sectors in the province of Valdivia (n = 559) using the ISAAC (International Study of Asthma and Allergies in Childhood) questionnaire. Results were compared to prevalence in urban Valdivia (n = 3105) by using data from ISAAC III study. Odds ratios (+95% confidence intervals) were calculated. No statistical significant differences were found for asthma ever and eczema symptoms stratified by residential sector, but a gradient could be shown for current asthma and rhinoconjunctivitis symptoms with urban living having highest and rural living having lowest prevalence. Rural living was inversely associated in a statistical significant way with current asthma (OR: 0.4; 95% CI: 0.2-0.9) and rhinoconjunctivitis symptoms (OR: 0.3; 95% CI: 0.2-0.7) in logistic regression analyses. Rural living seems to protect from asthma and respiratory allergies also in Chile, a South American country facing epidemiological transition. These data would be improved by clinical studies of allergic symptoms observed in studied sectors.
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Hesla HM, Gutzeit C, Stenius F, Scheynius A, Dahl H, Linde A, Alm J. Herpesvirus infections and allergic sensitization in children of families with anthroposophic and non-anthroposophic lifestyle - the ALADDIN birth cohort. Pediatr Allergy Immunol 2013; 24:61-5. [PMID: 23331530 DOI: 10.1111/pai.12030] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/30/2012] [Indexed: 11/27/2022]
Abstract
BACKGROUND Growing up in families with an anthroposophic lifestyle has been associated with reduced risk of allergic disease in children. The aim of this report was to assess whether children with this lifestyle are infected earlier with Epstein-Barr virus (EBV), which has been associated with reduced risk of allergic disease, and three other herpesviruses potentially involved in allergy development, namely Human herpesvirus 6 (HHV6), Human herpesvirus 7 (HHV7) and cytomegalovirus (CMV). METHODS Within the ALADDIN (Assessment of Lifestyle and Allergic Disease During Infancy), birth cohort study 157 children were categorized according to lifestyle into anthroposophic and non-anthroposophic. IgG-levels for EBV, HHV6, HHV7 and CMV were determined in plasma samples collected at ages 12 and 24 months and from parents. IgE levels against seven common allergens were analyzed at 24 months. RESULTS No significant differences in seroprevalence of EBV, HHV7 or CMV were detected at any age between the two lifestyle groups. The seroprevalence of HHV6 was significantly lower in the anthroposophic group at 24 months of age (74.6% vs. 87.5%, p-value 0.048). Further, no significant associations between allergic sensitization and seropositivity to any of the viruses were detected; however, an interaction effect of lifestyle could not be ruled out. CONCLUSIONS Our results indicate that there is no strong influence of exposure to the anthroposophic lifestyle on the time for infection with EBV, HHV6, HHV7 or CMV. These infections can therefore not be assumed to be important factors in the allergy-protective effect of this lifestyle.
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Affiliation(s)
- Helena Marell Hesla
- Department of Clinical Science and Education, Södersjukhuset, Karolinska Institutet, Sachs' Children and Youth Hospital, Stockholm, Sweden.
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Wang J, Cozen W, Thorne PS, Berhane K, Cerhan JR, Hartge P, Ward MH, De Roos AJ, Severson RK, Morton LM, Bernstein L, Linet MS, Colt JS. Household endotoxin levels and the risk of non-Hodgkin lymphoma. Cancer Causes Control 2013; 24:357-64. [PMID: 23277417 PMCID: PMC3800025 DOI: 10.1007/s10552-012-0121-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 11/30/2012] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Endotoxin, a component of the outer membrane of gram-negative bacteria, elicits a strong innate and inflammatory immune response associated with the secretion of proinflammatory cytokines, including tumor necrosis factor-alpha (TNF-α). Because TNF-α polymorphisms that increase TNF-α production are associated with an increased risk of non-Hodgkin lymphoma (NHL), we hypothesized that increased levels of household endotoxin would be associated with an increased NHL risk. METHODS We evaluated this association in the National Cancer Institute/Surveillance, Epidemiology and End Results (NCI/SEER) NHL multicenter population-based case-control study. Used vacuum cleaner bags were collected from participants during a home interview. Dust samples from the bags of 594 cases and 442 controls were analyzed for endotoxin [endotoxin unit (EU)/mg of dust] using the kinetic chromogenic Limulus amebocyte lysate assay. Multivariable logistic regression was used to estimate the effect of endotoxin on NHL risk adjusted for age, sex, race, education, study center, and farm exposure. RESULTS Endotoxin was not associated with NHL overall [odds ratio (OR) for highest quartile of endotoxin levels = 0.81, 95 % confidence interval (CI) = 0.55, 1.20; p for trend = 0.35] or with diffuse large B-cell lymphoma (OR = 0.63, 95 % CI = 0.34, 1.16; p = 0.31) or follicular lymphoma (OR = 1.07, 95 % CI = 0.61, 1.89; p = 0.73) subtypes. Both working and living on a farm were associated with higher household endotoxin levels compared to never working (p = 0.009) or living (p = 0.01) on a farm. Excluding farmers from the analysis did not change the results. CONCLUSIONS We found no evidence of a role for household endotoxin in NHL etiology.
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Affiliation(s)
- Jun Wang
- Department of Preventive Medicine, USC Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Wendy Cozen
- Department of Preventive Medicine, USC Keck School of Medicine, University of Southern California, Los Angeles, CA
- Department of Pathology, USC Keck School of Medicine, University of Southern California, Los Angeles, CA
- Norris Comprehensive Cancer Center, USC Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Peter S. Thorne
- Department of Occupational and Environmental Health, University of Iowa, Iowa City, Iowa
| | - Kiros Berhane
- Department of Preventive Medicine, USC Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - James R. Cerhan
- Division of Epidemiology, College of Medicine, Mayo Clinic, Rochester, MN
| | - Patricia Hartge
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
| | - Mary H. Ward
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
| | - Anneclaire J. De Roos
- Division of Public Health Sciences, Fred Hutchinson Cancer Research Center and Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA
| | - Richard K. Severson
- Department of Family Medicine and Public Health Sciences, School of Medicine, Wayne State University, Detroit, MI
| | - Lindsay M. Morton
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
| | - Leslie Bernstein
- Department of Preventive Medicine, USC Keck School of Medicine, University of Southern California, Los Angeles, CA
- Division of Cancer Etiology, Department of Population Sciences, Beckman Research Institute, City of Hope, Duarte, CA
| | - Martha S. Linet
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
| | - Joanne S. Colt
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD
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Jerschow E, McGinn AP, de Vos G, Vernon N, Jariwala S, Hudes G, Rosenstreich D. Dichlorophenol-containing pesticides and allergies: results from the US National Health and Nutrition Examination Survey 2005-2006. Ann Allergy Asthma Immunol 2012; 109:420-5. [PMID: 23176881 PMCID: PMC10576446 DOI: 10.1016/j.anai.2012.09.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 09/06/2012] [Accepted: 09/09/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Epidemiologic studies support the hypothesis that reduced microbial exposure in westernized societies promotes atopy. Dichlorophenols are widely used as pesticides and for chlorination of water. They have a strong bactericidal effect that could affect microflora in the environment. However, it is unknown whether their use is associated with a higher prevalence of allergies. OBJECTIVE To test the association between exposure to environmental pesticides represented by dichlorophenols and allergic sensitization measured by allergen-specific serum IgE levels in a US nationally representative sample of 2,211 persons 6 years and older in the National Health and Nutrition Examination Survey 2005-2006. METHODS Exposure to dichlorophenols was defined as high if their levels in urine were present at the 75th percentile and above. Association of the high exposure to dichlorophenols with sensitization to food and environmental allergens was assessed in logistic regression models after adjustment for sample weights and potential confounders. RESULTS Sensitizations to 1 or more food allergens were more common in those with exposure to 2 dichlorophenol metabolites. After multivariable adjustment, urine dichlorophenol levels at the 75th percentile and above were associated with the presence of sensitization to foods (odds ratio, 1.8; 95% confidence interval, 1.2-2.5; P = .003). No significant association was found between dichlorophenol exposure and sensitization to aeroallergens alone. CONCLUSION High urine levels of dichlorophenols are associated with the presence of sensitization to foods in a US population. Excessive use of dichlorophenols may contribute to the increasing incidence of food allergies in westernized societies.
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Affiliation(s)
- Elina Jerschow
- Albert Einstein College of Medicine/Montefiore Medical Center, Bronx, New York, USA.
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Osguthorpe JD. Pathophysiology of and potential new therapies for allergic rhinitis. Int Forum Allergy Rhinol 2012. [DOI: 10.1002/alr.21120] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- John David Osguthorpe
- Department of Otolaryngology-Head and Neck Surgery; Medical University of South Carolina; Charleston; SC
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Peakman M. Broadening the translational immunology landscape. Clin Exp Immunol 2012; 170:249-53. [DOI: 10.1111/j.1365-2249.2012.04671.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
SummaryIt is just over 5 years sinceClinical and Experimental Immunology came under the direction of a new team of Editors and made a concerted effort to refresh its approach to promoting clinical and applied immunology through its pages. There were two major objectives: to foster papers in a field which, at the time, we loosely termed ‘translational immunology’; and to create a forum for the presentation and discussion of immunology that is relevant to clinicians operating in this space. So, how are we doing with these endeavours? This brief paper aims to summarize some of the key learning points and successes and highlight areas in which translational gaps remain.
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Affiliation(s)
- M Peakman
- Department of Immunobiology, King's College London
- NIHR Comprehensive Biomedical Research Centre, Guy's and St Thomas’ NHS Foundation Trust and King's College London, London, UK
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Chen JP, Zhao WL, He NH, Gui Q, Xiong JP, Zhou HM, Wang Y, Chen S, Zhou P. Association of Hepatitis A exposure and TIM-1 with childhood allergic asthma. J Asthma 2012; 49:697-702. [PMID: 22857392 DOI: 10.3109/02770903.2012.694539] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Hepatitis A virus (HAV) receptor (TIM-1) polymorphism plays an important role in asthma and autoimmune diseases. Objective. To analyze the association of TIM-1 polymorphism and HAV infection with childhood allergic asthma in Southwest China. METHODS TIM-1 exon 4 (157insMTTTVP) and two polymorphism loci, -416G>C and -1454G>A, in the HAV receptor promoter region were studied. Polymerase chain reaction (PCR) was used to test the genotypes of three polymorphism loci among 579 cases of asthma and 524 controls. The HAV infection status was determined in a case-control study with stratified analysis. RESULTS HAV exposure associated with childhood allergic asthma in the study population was compared with controls (odds ratio (OR) = 0.181, 95% confidence interval (CI) 0.126-0.260, p < .001). The -416G>C polymorphism was associated with asthma (OR = 1.384, 95% CI 1.148-1.669, p < .001), but the insertion variant 157delMTTTVP of exon 4 and the -1454G>A polymorphism were not. CONCLUSION Our results indicated that the -416G>C polymorphism of the TIM-1 gene is associated with childhood allergic asthma, providing a better understanding of the pathogenesis of the allergic asthma among children aged below 15 years in Southwest China.
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Affiliation(s)
- Jian-Ping Chen
- Department of Pediatrics, Southwest Hospital, The Third Military Medical University, Chongqing 400038, China
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Sekerkova A, Polackova M, Striz I. Detection of Phl p 1, Phl p 5, Phl p 7 and Phl p 12 specific IgE antibodies in the sera of children and adult patients allergic to Phleum pollen. Allergol Int 2012; 61:339-46. [PMID: 22526205 DOI: 10.2332/allergolint.11-oa-0372] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Accepted: 12/27/2011] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Grasses belong to major sources of inhaled allergens. The knowledge of particular molecules responsible for hypersensitivity is of crucial importance for better understanding of individual differences among single allergic subjects and allergic populations living in various world-areas. METHODS Specific-IgE-antibodies against Phl p 1, Phl p 5, Phl p 7, Phl p 12 were detected in a group of 130 Phleum-allergic-subjects (82 children, 48 adults). RESULTS Phl p 1 antibodies were detected in most pediatric and adult patients, however, the children were associated with higher RAST classes more often. Anti-Phl p 5-antibodies were found more frequently in adults. An increase was observed in the number of pediatric patients reacting to Phl p 7 and Phl p 12. There were no differences in concentrations of specific-IgE against Phl p 5, Phl p 7 and Phl p 12 depending on age. Almost 10% of allergic children produced antibodies directed exclusively against minor allergens or did not produce specific-IgE-antibodies against tested molecules. Part of the patients reacted to profilin and calcium-binding protein originating from only one source (Phl p 12/Bet v 2 and Phl p 7/Bet v 4). CONCLUSIONS Antibodies against Phl p 1 and Phl p 5 can be used as a marker of allergy to grasses in adult patients. Children reacted exclusively to minor allergens more frequently than adults. Prolonged allergen exposure is evidently necessary to induce sensitization to Phl p 5. A high level of homology between profilins and calcium-binding proteins enables only one allergen to be used for diagnostic purposes but a possibility of a reaction to species-bound epitopes should be taken into account.
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Affiliation(s)
- Alena Sekerkova
- Department of Clinical and Transplant Immunology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
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Diesner SC, Förster-Waldl E, Olivera A, Pollak A, Jensen-Jarolim E, Untersmayr E. Perspectives on immunomodulation early in life. Pediatr Allergy Immunol 2012; 23:210-23. [PMID: 22299601 DOI: 10.1111/j.1399-3038.2011.01259.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The immune system early in life is characterized by immature activation and function of immune cells and a preponderance of Th2 cytokines. Together with other factors such as genetics and epigenetics, these immature immune responses might prone newborns susceptible to severe infections as well as allergic diseases. Immunomodulation therapy may have potential as therapeutic strategy against those disorders and might have implication in early-life interventions in the future. In this review, we will focus on two immunomodulatory substance classes, Toll-like receptor (TLR) ligands and sphingolipids, which are the focus of extensive research to date. Both TLRs and sphingolipid receptors have a very distinct distribution pattern and function on immune cells. Therefore, they can potentially modulate and balance immune responses, which might be in particular beneficial for the immaturity of the immune response early in life.
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Affiliation(s)
- Susanne C Diesner
- Department of Pathophysiology and Allergy Research, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Waehringer Guertel 18-20, Vienna, Austria
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Abstract
PURPOSE OF REVIEW To identify and discuss recent studies relating prenatal and early-life environmental exposures to the development of asthma and allergic disease. RECENT FINDINGS New studies show that prenatal and early-life stress can alter infant immune profiles, increasing risk for asthma and allergy. Mounting evidence implicates indoor and outdoor air pollution in the origins of allergic disease, while Vitamin D intake and a Mediterranean diet may be protective. The role of early-life fever and infection remain controversial, with recent studies yielding conflicting results and new evidence indicating that previous studies may have been confounded. New studies are increasingly focused on environmental 'imprinting' of the infant gut microbiota, which is a critical determinant of immune system development. Early exposures impacting the intestinal microbiota include mode of delivery, infant diet, and use of antibiotics - factors that are also associated with childhood asthma and allergic disease. SUMMARY This overview highlights environmental exposures during the in-utero and ex-utero time periods that are potential stimuli for the early programming of asthma and allergy. Special consideration is given for the potential role of intestinal microbiota. Future studies in this field promise to inform health policy and intervention strategies for the prevention of asthma and allergic disease.
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Abstract
Allergic rhinitis is a very common disorder that affects people of all ages, peaking in the teenage years. It is frequently ignored, underdiagnosed, misdiagnosed, and mistreated, which not only is detrimental to health but also has societal costs. Although allergic rhinitis is not a serious illness, it is clinically relevant because it underlies many complications, is a major risk factor for poor asthma control, and affects quality of life and productivity at work or school. Management of allergic rhinitis is best when directed by guidelines. A diagnostic trial of a pharmacotherapeutic agent could be started in people with clinically identified allergic rhinitis; however, to confirm the diagnosis, specific IgE reactivity needs to be recorded. Documented IgE reactivity has the added benefit of guiding implementation of environmental controls, which could substantially ameliorate symptoms of allergic rhinitis and might prevent development of asthma, especially in an occupational setting. Many classes of drug are available, effective, and safe. In meta-analyses, intranasal corticosteroids are superior to other treatments, have a good safety profile, and treat all symptoms of allergic rhinitis effectively. First-generation antihistamines are associated with sedation, psychomotor retardation, and reduced academic performance. Only immunotherapy with individually targeted allergens has the potential to alter the natural history of allergic rhinitis. Patients' education is a vital component of treatment. Even with the best pharmacotherapy, one in five affected individuals remains highly symptomatic, and further research is needed in this area.
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MESH Headings
- Asthma/etiology
- Diagnosis, Differential
- Humans
- Occupational Diseases/etiology
- Rhinitis, Allergic, Perennial/complications
- Rhinitis, Allergic, Perennial/diagnosis
- Rhinitis, Allergic, Perennial/physiopathology
- Rhinitis, Allergic, Perennial/therapy
- Rhinitis, Allergic, Seasonal/complications
- Rhinitis, Allergic, Seasonal/diagnosis
- Rhinitis, Allergic, Seasonal/physiopathology
- Rhinitis, Allergic, Seasonal/therapy
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Perinatal programming of asthma: the role of gut microbiota. Clin Dev Immunol 2011; 2012:932072. [PMID: 22110540 PMCID: PMC3216351 DOI: 10.1155/2012/932072] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 09/14/2011] [Indexed: 12/22/2022]
Abstract
Perinatal programming, a dominant theory for the origins of cardiovascular disease, proposes that environmental stimuli influence developmental pathways during critical periods of prenatal and postnatal development, inducing permanent changes in metabolism. In this paper, we present evidence for the perinatal programming of asthma via the intestinal microbiome. While epigenetic mechanisms continue to provide new explanations for the programming hypothesis of asthma development, it is increasingly apparent that the intestinal microbiota plays an independent and potentially interactive role. Commensal gut bacteria are essential to immune system development, and exposures disrupting the infant gut microbiota have been linked to asthma. This paper summarizes the recent findings that implicate caesarean delivery, breastfeeding, perinatal stress, probiotics, and antibiotics as modifiers of infant gut microbiota in the development of asthma.
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Boneberger A, Weiss EH, Calvo M, Torres L, Wagner J, Kabesch M, Radon K. Environmental factors in infancy and ulcerative colitis in the Central South of Chile: a case-control study. J Crohns Colitis 2011; 5:392-6. [PMID: 21939911 DOI: 10.1016/j.crohns.2011.03.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 03/07/2011] [Accepted: 03/07/2011] [Indexed: 01/17/2023]
Abstract
BACKGROUND AND AIMS Evidence for the role of the hygiene hypothesis and the development of Ulcerative Colitis (UC) is unclear. We aimed to explore the association between environmental factors in infancy and UC. METHODS A hospital-based case-control study (52 UC cases, response: 77%, 174 age- , sex and place of living matched controls, response: 62%) was carried out in the Central South of Chile in 2009/2010. Patients or parents underwent a personal interview about early life experiences. RESULTS High paternal education (adjusted Odds Ratio (aOR): 2.1; 95% CI: 1.0-4.5) as proxy for socioeconomic status was positively associated with case status in the final multivariate logistic regression model. Likewise, having older siblings was a risk factor for UC (aOR: 2.2; 95%CI: 1.1.-4.4). CONCLUSIONS The importance for some early life environmental factors in the development of UC was established. However, the role of the hygiene hypothesis could not be confirmed for all environmental factors.
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Affiliation(s)
- Anja Boneberger
- Unit for Occupational and Environmental Epidemiology & Net Teaching, Institute and Outpatient Clinic for Occupational-, Social- and Environmental Medicine, University Hospital of Munich (LMU), Munich, Germany.
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Ponsonby AL, Hughes AM, Lucas RM. The ‘hygiene hypothesis’ and the development of multiple sclerosis. Neurodegener Dis Manag 2011. [DOI: 10.2217/nmt.11.38] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
SUMMARY We review evidence linking inadequate microbial exposure in early life to the development of multiple sclerosis (MS). There is some supportive, but not conclusive evidence for a role of a hygienic environment in early life and MS. Population-level studies of MS are consistent with the hygiene hypothesis but are limited by methodological issues. Late infection with Epstein–Barr virus (EBV) has been prospectively associated with MS and must be incorporated into any model where the hygiene hypothesis is implicated in the development of MS. One possibility is that inadequate microbial exposure in early life contributes to a dysregulated host immune response to EBV. Two areas of particular interest include the potential role for helminthic infection in biasing the human immune response away from the immune profile associated with MS and also the role of microbial exposure in training the development of the EBV-specific immune response.
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Affiliation(s)
- Anne-Louise Ponsonby
- Murdoch Childrens Research Institute, The Royal Children’s Hospital, Parkville Victoria 3052, Melbourne, Australia
| | - Ann Maree Hughes
- National Centre for Epidemiology & Population Health, The Australian National University, Canberra, Australia
| | - Robyn Marjorie Lucas
- National Centre for Epidemiology & Population Health, The Australian National University, Canberra, Australia
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Current world literature. Curr Opin Allergy Clin Immunol 2011; 11:150-6. [PMID: 21368622 DOI: 10.1097/aci.0b013e3283457ab0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Weise C, Zhu Y, Ernst D, Kühl AA, Worm M. Oral administration of Escherichia coli Nissle 1917 prevents allergen-induced dermatitis in mice. Exp Dermatol 2011; 20:805-9. [PMID: 21740462 DOI: 10.1111/j.1600-0625.2011.01326.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND The prevalence of allergies has been linked to Western life style factors including a decrease of microbial exposure. Probiotics, such as Escherichia coli Nissle 1917 (EcN), have been shown to be beneficial for prevention and treatment of several chronic inflammatory diseases. OBJECTIVE The aim of this study was to investigate the impact of oral EcN administration on development and outcome of allergen-induced dermatitis. METHODS In sensitized BALB/c mice, skin inflammation was induced by topical allergen application. EcN was administered orally in a preventive manner. Severity of dermatitis was analysed by evaluation of skin score, local cellular and cytokine profile. The systemic immune response was assessed by analysis of immunoglobulins and allergen-dependent cytokine response. RESULTS Oral EcN administration improved allergen-induced dermatitis dose-dependently. In parallel, a reduction of epidermal thickness and infiltrating immune cells together with an enhanced number of forkhead box P3 (Foxp3)(+) cells and a trend of increased IFNγ, IL-10 and TGFβ expression was detected in eczematous skin. In allergen-stimulated splenocytes reduced IL-4 and IFNγ along with an elevated IL-10 production and a tendency to an increased TGFβ secretion were observed. CONCLUSIONS Our findings indicate that EcN alters the local allergen-induced immune response by increase of Foxp3(+) cells and by favouring an immunoregulatory cytokine pattern. Thus, oral administration of EcN might be an effective strategy in prevention and potentially therapy of allergic inflammatory skin diseases.
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Affiliation(s)
- Christin Weise
- Allergy-Center-Charité, Department of Dermatology and Allergy, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Wingender G, Rogers P, Batzer G, Lee MS, Bai D, Pei B, Khurana A, Kronenberg M, Horner AA. Invariant NKT cells are required for airway inflammation induced by environmental antigens. ACTA ACUST UNITED AC 2011; 208:1151-62. [PMID: 21624935 PMCID: PMC3173256 DOI: 10.1084/jem.20102229] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
House dust contains antigens capable of activating mouse and human iNKT cells, contributing to allergen-induced airway inflammation. Invariant NKT cells (iNKT cells) are a unique subset of T lymphocytes that rapidly carry out effector functions. In this study, we report that a majority of sterile house dust extracts (HDEs) tested contained antigens capable of activating mouse and human iNKT cells. HDEs had adjuvant-like properties in an ovalbumin (OVA)-induced asthma model, which were dependent on Vα14i NKT cells, as vaccinated animals deficient for iNKT cells displayed significantly attenuated immune responses and airway inflammation. Furthermore, the administration of HDEs together with OVA mutually augmented the synthesis of cytokines by Vα14i NKT cells and by conventional CD4+ T cells in the lung, demonstrating a profound immune response synergy for both Th2 cytokines and IL-17A. These data demonstrate that iNKT cell antigens are far more widely dispersed in the environment than previously anticipated. Furthermore, as the antigenic activity in different houses varied greatly, they further suggest that iNKT cell responses to ambient antigens, particular to certain environments, might promote sensitization to conventional respiratory allergens.
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Affiliation(s)
- Gerhard Wingender
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA
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Boneberger A, Haider D, Baer J, Kausel L, Von Kries R, Kabesch M, Radon K, Calvo M. Environmental risk factors in the first year of life and childhood asthma in the Central South of Chile. J Asthma 2011; 48:464-9. [PMID: 21548831 DOI: 10.3109/02770903.2011.576740] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Childhood asthma has a high prevalence in South America--a region of the world currently undergoing a thorough modernization and transition process. Asthma in South America is mainly associated with poor urban environment, which actually may challenge the role of the hygiene hypothesis. We systematically assessed the impact of environmental factors in the first year of life on asthma. METHODS A case-control study including 188 asthmatics and 294 hospital-based controls aged 6-15 years was carried out in the Central South of Chile. Parents of study participants completed a computer-assisted interview on environmental factors (such as birth order, day-care attendance, pneumonia infection, regular animal and furry pet contact, and environmental tobacco smoke exposure) in the first year of life and potential confounders. Atopy was assessed using skin prick tests. Multivariate logistic regression models were calculated to assess the association between exposures and asthma, adjusting for potential confounders. RESULTS Day-care attendance (OR = 0.31; 95% CI: 0.10, 0.94) and regular farm animal contact (OR = 0.38; 95% CI: 0.17, 0.85) were inversely related to childhood asthma in the logistic regression models. Pneumonia infection (OR = 2.24; 95% CI: 1.21, 4.16) and mold or dampness in the home (OR = 1.87; 95% CI: 1.18, 2.97) in the first year of life were positively associated with asthma. CONCLUSION Our results suggest that the hygiene hypothesis is also applicable in the Chilean setting, a South American country in epidemiological transition.
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Affiliation(s)
- Anja Boneberger
- Unit for Occupational and Environmental Epidemiology, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, University Hospital of Munich, Munich, Germany
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Boettler T, von Herrath M. Protection against or triggering of Type 1 diabetes? Different roles for viral infections. Expert Rev Clin Immunol 2011; 7:45-53. [PMID: 21162649 DOI: 10.1586/eci.10.91] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The emergence of autoreactivity that ultimately destroys insulin-producing β-cells and causes Type 1 diabetes (T1D) is a result of genetic susceptibility and environmental factors, such as viral infections. The ability to induce strong cellular immune responses and to cause inflammation in the target organ makes viral infections prime candidates for the initiation of islet autoreactivity. Indeed, certain viruses have been linked to the occurrence of T1D based on epidemiological, serological and histological findings; and several rodent studies clearly demonstrate that viral infections can trigger autoimmunity. However, viruses have also been shown to efficiently prevent autoimmunity, which underlines the beneficial aspects of exposure to microbial agents as suggested by the hygiene hypothesis. Here, we will try to untangle some aspects of the complex interplay between viruses and the immune system and we will recapitulate by what rationale certain viruses have been associated with T1D.
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Affiliation(s)
- Tobias Boettler
- La Jolla Institute for Allergy and Immunology - LIAI, 9420 Athena Circle, La Jolla, CA 92037, USA
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