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Avoidance of allergens as an environmental method in the prevention of inhaled allergy symptoms. Allergol Immunopathol (Madr) 2020; 48:745-752. [PMID: 31879043 DOI: 10.1016/j.aller.2019.06.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 06/25/2019] [Indexed: 11/20/2022]
Abstract
Asthma and other inhaled allergies are some of the most common paediatric diseases. The association of exposure to allergens with induction and exacerbation of symptoms has been proven. The majority of allergens are permanently or periodically suspended in the air, which leads to impaired quality of life for sensitive patients. Therefore, many methods of prevention and therapy of allergic diseases have been developed. The method of allergen exposure avoidance is often the first and the most significant measure. The present research has been conducted to evaluate, based on scientific data, which measures have the most reliable evidence of effectiveness. Environmental allergen avoidance methods, despite limited evidence supporting their clinical efficacy, are listed as the main therapeutic approaches in most recommendations. The significance of the holistic approach is also emphasised: only simultaneous introduction of several avoidance methods can bring possibly beneficial effects for the patient.
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2
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van Boven FE, Arends LR, Braunstahl G, van Wijk RG. A reintroduction of environmental mite allergen control strategies for asthma treatment and the debate on their effectiveness. Clin Exp Allergy 2019; 49:400-409. [PMID: 30659677 PMCID: PMC6850033 DOI: 10.1111/cea.13340] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 12/21/2018] [Accepted: 01/09/2019] [Indexed: 12/19/2022]
Abstract
Asthma affects three hundred million people worldwide. The effectiveness of house dust mite allergen control for asthma treatment is debatable. One aspect that has been little discussed in existing meta-analyses is the possible role of environmental strategies. Here, we reintroduce the previously defined strategies for mite allergen control and discuss their importance to the debate on clinical effectiveness. The strategy of concurrent bedroom interventions is related to the combined use of a priori defined interventions, while the strategy of exposure-based control relates to the treatment of relevant textiles after assessing exposure. The air purification strategy aims to purify the human breathing zone of airborne allergens. In Western European patient practice, the use of these strategies differs. A post hoc study of the dominant Cochrane review by Gøtzsche and Johansen (Cochrane Database of Systematic Reviews, 2008, Art. No: CD001187) appears to indicate that a majority of the underlying trials reported on the strategy of concurrent bedroom interventions, which were mainly executed in a minimal manner. Some trials have reported on the air purification strategy and may potentially alter the debate on effectiveness. No trial has reported on the strategy of exposure-based control. We therefore hypothesize that the absence of evidence for the effectiveness of mite allergen control for asthma treatment applies to the strategy of concurrent bedroom interventions. The evidence-based effectiveness of the exposure-based control strategy appears to be undetermined. The results of our post hoc reanalysis urge that future meta-analyses of mite allergen control should a priori define the environmental strategy under study. Future trials of mite allergen control are warranted to test the exposure-based strategy as well as the sparsely tested strategy of air purification.
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Affiliation(s)
- Frank E. van Boven
- Department of Internal MedicineSection of AllergologyErasmus Medical CenterRotterdamThe Netherland
| | - Lidia R. Arends
- Department of BiostatisticsErasmus Medical CenterRotterdamThe Netherlands
- Department of Psychology, Education & Child StudiesErasmus University RotterdamRotterdamThe Netherlands
| | - Gert‐Jan Braunstahl
- Department of PulmonologySint Franciscus Vlietland GroepRotterdamThe Netherlands
- Department of PulmonologyErasmus Medical CenterRotterdamThe Netherlands
| | - Roy Gerth van Wijk
- Department of Internal MedicineSection of AllergologyErasmus Medical CenterRotterdamThe Netherland
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3
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Park JS, Son JH, Park CS, Chang HS. Clinical Implications of Single Nucleotide Polymorphisms in Diagnosis of Asthma and its Subtypes. Yonsei Med J 2019; 60:1-9. [PMID: 30554485 PMCID: PMC6298887 DOI: 10.3349/ymj.2019.60.1.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 09/11/2018] [Accepted: 09/15/2018] [Indexed: 11/27/2022] Open
Abstract
For the past three decades, a large number of genetic studies have been performed to examine genetic variants associated with asthma and its subtypes in hopes of gaining better understanding of the mechanisms underlying disease pathology and to identify genetic biomarkers predictive of disease outcomes. Various methods have been used to achieve these objectives, including linkage analysis, candidate gene polymorphism analysis, and genome-wide association studies (GWAS); however, the degree to which genetic variants contribute to asthma pathogenesis has proven to be much less significant than originally expected. Subsequent application of GWAS to well-defined phenotypes, such as occupational asthma and non-steroidal anti-inflammatory drugexacerbated respiratory diseases, has overcome some of these limitations, although with only partial success. Recently, a combinatorial analysis of single nucleotide polymorphisms (SNPs) identified by GWAS has been used to develop sets of genetic markers able to more accurately stratify asthma subtypes. In this review, we discuss the implications of the identified SNPs in diagnosis of asthma and its subtypes and the progress being made in combinatorial analysis of genetic variants.
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Affiliation(s)
- Jong Sook Park
- Division of Allergy and Respiratory Medicine, Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea
| | - Ji Hye Son
- Department of Interdisciplinary Program in Biomedical Science, Graduate School, Soonchunhyang University, Bucheon, Korea
| | - Choon Sik Park
- Division of Allergy and Respiratory Medicine, Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea
| | - Hun Soo Chang
- Department of Interdisciplinary Program in Biomedical Science, Graduate School, Soonchunhyang University, Bucheon, Korea.
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4
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Genuneit J, Seibold AM, Apfelbacher CJ, Konstantinou GN, Koplin JJ, La Grutta S, Logan K, Perkin MR, Flohr C. Overview of systematic reviews in allergy epidemiology. Allergy 2017; 72:849-856. [PMID: 28052339 DOI: 10.1111/all.13123] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/01/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND There is a substantial body of evidence on the epidemiology of allergic conditions, which has advanced the understanding of these conditions. We aimed to systematically identify systematic reviews and meta-analyses on the epidemiology of allergic diseases to assess what has been studied comprehensively and what areas might benefit from further research. METHODS We searched PubMed and EMBASE up to 12/2014 for systematic reviews on epidemiological research on allergic diseases. We indexed diseases and topics covered and extracted data on the search characteristics of each systematic review. RESULTS The search resulted in 3991 entries after removing duplicates, plus 20 other items found via references and conference abstracts; 421 systematic reviews were relevant and included in this overview. The majority contained some evidence on asthma (72.9%). Allergic rhinitis, atopic eczema and food hypersensitivity were covered in 15.7%, 24.5% and 9.0%, respectively. Commonly studied risk factors for atopic eczema included dietary and microbial factors, while for asthma, pollution and genetic factors were often investigated in systematic reviews. There was some indication of differing search characteristics across topics. CONCLUSION We present a comprehensive overview with an indexed database of published systematic reviews in allergy epidemiology. We believe that this clarifies where most research interest has focussed and which areas could benefit from further research. We propose that this effort is updated every few years to include the most recently published evidence and to extend the search to an even broader list of hypersensitivity/allergic disorders.
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Affiliation(s)
- J. Genuneit
- Institute of Epidemiology and Medical Biometry; Ulm University; Ulm Germany
| | - A. M. Seibold
- Institute of Epidemiology and Medical Biometry; Ulm University; Ulm Germany
| | - C. J. Apfelbacher
- Institute of Epidemiology and Preventive Medicine; University of Regensburg; Regensburg Germany
| | - G. N. Konstantinou
- Department of Allergy and Clinical Immunology; 424 General Military Training Hospital; Thessaloniki Greece
| | - J. J. Koplin
- Murdoch Children's Research Institute; University of Melbourne; Melbourne VIC Australia
| | - S. La Grutta
- National Research Council of Italy; Institute of Biomedicine and Molecular Immunology; Palermo Italy
| | - K. Logan
- Children's Allergies Department; Division of Asthma, Allergy and Lung Biology; King's College London; London UK
| | - M. R. Perkin
- Population Health Research Institute; St George's, University of London; London UK
| | - C. Flohr
- Unit for Population-Based Dermatology Research; St John's Institute of Dermatology; King's College London and Guy's and St Thomas’ NHS Foundation; London UK
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Parande Shirvan S, Ebrahimby A, Dousty A, Maleki M, Movassaghi A, Borji H, Haghparast A. Somatic extracts of Marshallagia marshalli downregulate the Th2 associated immune responses in ovalbumin-induced airway inflammation in BALB/c mice. Parasit Vectors 2017; 10:233. [PMID: 28494800 PMCID: PMC5427607 DOI: 10.1186/s13071-017-2159-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 04/25/2017] [Indexed: 12/26/2022] Open
Abstract
Background Recently the role of gastrointestinal nematodes in modulating the immune responses in inflammatory and immune-mediated conditions such as allergy and autoimmune diseases has been introduced. This is mainly due to the suppressive effects of somatic and excretory secretory (ES) products of nematodes on the immune responses. In this study, we evaluated the immunomodulatory potentials of somatic products of Marshallagia marshalli, a gastrointestinal nematodes of sheep, to suppress the immune-mediated responses in a murine model of allergic airway inflammation. BALB/c mice were intraperitoneally (IP) sensitized with ovalbumin (OVA)/Alum and then challenged with 1% OVA. Somatic products of M. marshalli were administered during each sensitization. The effects of somatic products on development of allergic airway inflammation were evaluated by analyzing inflammatory cells recruitment, histopathological changes, cytokines production (IL-4, IL-13, IL-10, TGF-β) and serum antibody titers (IgG1, IgG2a). Results Somatic products of M. marshalli were able to suppress the induction of allergic airway inflammation in mice. Modulation of Th2 type responses (IL-4, IL-13, IgG1) via upregulations of IL-10 and TGF-β production was observed after injection of somatic products of M. marshalli. In addition, inflammatory cells infiltration and pathological disorders were significantly diminished following administration of somatic products. Conclusions Our data raised the possibility that helminths could be a potential therapeutic candidate to alleviate the inflammatory conditions in allergic asthma. According to these results, we concluded that M. marshalli may contain immune-modulatory molecules that attenuate allergic airway inflammation via induction of regulatory cytokines. Further investigations are required to identify molecules that might have potentials for development of novel therapeutic targets.
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Affiliation(s)
- Sima Parande Shirvan
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran
| | - Azadeh Ebrahimby
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran
| | - Arezoo Dousty
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran
| | - Mohsen Maleki
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran
| | - Ahmadreza Movassaghi
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran
| | - Hassan Borji
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran.
| | - Alireza Haghparast
- Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran. .,Division of Biotechnology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, P. O. Box: 91775-1793, Mashhad, Iran.
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Cipriani F, Calamelli E, Ricci G. Allergen Avoidance in Allergic Asthma. Front Pediatr 2017; 5:103. [PMID: 28540285 PMCID: PMC5423906 DOI: 10.3389/fped.2017.00103] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 04/21/2017] [Indexed: 01/31/2023] Open
Abstract
Allergic asthma is the most frequent disease among the chronic respiratory disorders in pediatric age with an important social impact. In the last years, many efforts have been made to identify effective preventive approaches to get a better control of symptoms and to obtain the best future outcomes for the patients. In patients with allergic asthma triggered by the exposure to indoor allergens, the avoidance is the first intervention to prevent the appearance or the worsening of bronchial symptoms. This review article summarized the most recent evidence from literature about the efficacy of specific control interventions for the most important allergens. Even if a wide spectrum of interventions has been suggested and may help to reduce exposure to trigger allergy for sensitized patients suffering from respiratory allergy, evidence supporting the efficacy of these approaches is still weak and subject of controversy. However, the exposure control to specific airborne allergens is still widely recommended and may be effective as part of a holistic approach to reduce the severity of allergic respiratory symptoms in sensitized individuals.
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Affiliation(s)
- Francesca Cipriani
- Pediatric Unit, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Elisabetta Calamelli
- Pediatric Unit, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
- Pediatric and Neonatology Unit, Imola Hospital, Bologna, Italy
| | - Giampaolo Ricci
- Pediatric Unit, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
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Markevych I, Baumbach C, Standl M, Koletzko S, Lehmann I, Bauer CP, Hoffmann B, von Berg A, Berdel D, Heinrich J. Early life travelling does not increase risk of atopic outcomes until 15 years: results from GINIplus and LISAplus. Clin Exp Allergy 2017; 47:395-400. [PMID: 28122145 DOI: 10.1111/cea.12891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 01/04/2017] [Accepted: 01/12/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Westernized lifestyle has been blamed for allergy epidemics. One of its characteristics is increased distances and frequency of travelling from early life onwards. Early life travelling to places which substantially differ from home environment in terms of climate, vegetation and food could increase the exposure to further unknown allergens and hence promote the development of allergies, but no epidemiological study has investigated this speculation. METHODS Detailed data on travelling during the first 2 years of life as well as a range of atopic outcomes along with potential confounders up to age 15 years were collected prospectively within two large population-based multicentre German birth cohorts - GINIplus and LISAplus. Farthest travelling destination (within Germany; middle/northern/eastern Europe; southern Europe; outside Europe), total number of trips and their combination were considered as exposures. Six atopic outcomes were used: (1) doctor-diagnosed asthma, (2) doctor-diagnosed allergic rhinitis, (3) nose and eye symptoms, (4) sensitization to food allergens, (5) sensitization to indoor and (6) outdoor inhalant allergens. Longitudinal associations between each exposure and health outcome pair were analysed using generalized estimation equations (GEEs). RESULTS The results of our longitudinal analyses of 5674 subjects do not support the research hypothesis that travelling abroad to different regions in Europe or beyond Europe and frequency of travelling increase prevalence of doctor-diagnosed asthma and allergic rhinitis, nose and eye symptoms and allergic sensitization up to 15 years of age. Furthermore, there was no indication of age-varying effects. CONCLUSIONS Early life travelling does not seem to increase risk of atopic outcomes. Nevertheless, as we could not account for the type of visited environment or length of stay, these first findings should be interpreted with caution.
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Affiliation(s)
- I Markevych
- Institute of Epidemiology I, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Division of Metabolic and Nutritional Medicine, Dr. von Hauner Children's Hospital, Ludwig-Maximilians-University of Munich, Munich, Germany.,Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich (LMU), Munich, Germany
| | - C Baumbach
- Research Unit of Molecular Epidemiology, Institute of Epidemiology II, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - M Standl
- Institute of Epidemiology I, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - S Koletzko
- Division of Paediatric Gastroenterology and Hepatology, Dr. von Hauner Children's Hospital Munich, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - I Lehmann
- Department of Environmental Immunology/Core Facility Studies, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - C-P Bauer
- Department of Pediatrics, Technical University of Munich, Munich, Germany
| | - B Hoffmann
- Centre for Health and Society, Institute of Occupational, Social and Environmental Medicine, Heinrich-Heine University of Düsseldorf, Düsseldorf, Germany
| | - A von Berg
- Research Institute, Department of Pediatrics, Marien-Hospital Wesel, Wesel, Germany
| | - D Berdel
- Research Institute, Department of Pediatrics, Marien-Hospital Wesel, Wesel, Germany
| | - J Heinrich
- Institute of Epidemiology I, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich (LMU), Munich, Germany
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8
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Matsumoto FY, Gonçalves TRT, Solé D, Wandalsen GF. Specific Nasal Provocation Test with Dermatophagoides Pteronyssinus, Monitored by Acoustic Rhinometry, in Children with Rhinitis. Am J Rhinol Allergy 2017; 31:7-11. [DOI: 10.2500/ajra.2017.31.4392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Background Currently, the diagnosis of allergic rhinitis (AR) is arrived at predominantly by a clinical history and by systemic sensitization tests, but specific nasal provocation tests (NPT) may establish a better direct correlation between etiologic surveyed allergens and nasal symptoms. Objectives To standardize the specific NPT with one of the most important house-dust mites, Dermatophagoides pteronyssinus, monitored by acoustic rhinometry, in children and adolescents, and propose a simplified specific NPT to improve its clinical applicability as a diagnostic tool. Methods Sixteen controls (group 1) and 17 patients with an AR diagnosis sensitized to D. pteronyssinus (group 2) underwent a specific NPT with D. pteronyssinus. The acoustic rhinometry was performed after instillation of 0.15 mL of increasing concentrations of D. pteronyssinus (5000 BU/mL). The test was finalized after (1) instillation of the final concentration of D. pteronyssinus, or (2) after a 20% or more reduction in the volume of the first 5 cm of the nasal cavity (V5), or (3) a score of >3 in the symptoms questionnaire (a score from 0 to 7). A simplified specific NPT with two concentrations was proposed and implemented in a group of 10 patients with AR (group 3). Results At the end of the specific NPT, the median (range) variation in V5 was -5.7% (-9 to 4%) in the control group and -22.8% (-24 to -20%) in group 2. None of the patients in the control group and 88% of group 2 (15/17) showed positive specific NPT results. The simplified specific NPT triggered a positive response in 80% of patients in group 3, with median (range) V5 variation of -30.4% (-36 to -20%). Conclusion This protocol has been proven safe and useful to differentiate between children and adolescents with AR and controls. Concentrations of 1:1000 and 1:100 D. pteronyssinus were the best for use in simplified specific NPT, which made it simpler and faster, and expanded its clinical applicability.
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Affiliation(s)
- Fausto Yoshio Matsumoto
- Division of Allergy, Clinical Immunology and Rheumatology, Department of Pediatrics, Federal University of Sao Paulo, Sao Paulo, Brazil
| | | | - Dirceu Solé
- Division of Allergy, Clinical Immunology and Rheumatology, Department of Pediatrics, Federal University of Sao Paulo, Sao Paulo, Brazil
| | - Gustavo Falbo Wandalsen
- Division of Allergy, Clinical Immunology and Rheumatology, Department of Pediatrics, Federal University of Sao Paulo, Sao Paulo, Brazil
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Lloyd-Lavery A, Rogers NK, Hatfield SJ, Grindlay D, Barnett R, Thomas KS. What's new in atopic eczema? An analysis of systematic reviews published in 2014. Part 2. Treatment and prevention. Clin Exp Dermatol 2016; 42:3-7. [DOI: 10.1111/ced.12967] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2016] [Indexed: 12/16/2022]
Affiliation(s)
- A. Lloyd-Lavery
- Department of Dermatology; Churchill Hospital; Oxford University Hospitals NHS Foundation Trust; Oxford UK
| | - N. K. Rogers
- Centre of Evidence Based Dermatology; University of Nottingham; Nottingham UK
| | | | - D. Grindlay
- Centre of Evidence Based Dermatology; University of Nottingham; Nottingham UK
| | - R. Barnett
- Department of Dermatology; Churchill Hospital; Oxford University Hospitals NHS Foundation Trust; Oxford UK
| | - K. S. Thomas
- Centre of Evidence Based Dermatology; University of Nottingham; Nottingham UK
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Abstract
The term “immune” pertains to the body keeping itself free from diseases, not to trigger any diseases. In this regard, it makes sense for us to divide antigenicity into immunogenicity and allergenicity. This distinction allows for the characterization of all types of modern antigens, i.e., to evaluate and modify a priori the allergenicity of an antigen before it is applied to humans. In this chapter, we also formulated the hypothesis that “Balanced Stimulation by Whole Antigens” is essential for immune development. This hypothesis revives the practicality of the “Hygiene Hypothesis” and can provide a fundamental solution to curb the increasing prevalence of allergic disease, namely, early exposure, at 0–1 year old or earlier, in utero, of representative allergens/protein antigens with immunogenicity retained or improved and allergenicity attenuated or eliminated.
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Abstract
Over the past three decades, a large number of genetic studies have been aimed at finding genetic variants associated with the risk of asthma, applying various genetic and genomic approaches including linkage analysis, candidate gene polymorphism studies, and genome-wide association studies (GWAS). However, contrary to general expectation, even single nucleotide polymorphisms (SNPs) discovered by GWAS failed to fully explain the heritability of asthma. Thus, application of rare allele polymorphisms in well defined phenotypes and clarification of environmental factors have been suggested to overcome the problem of 'missing' heritability. Such factors include allergens, cigarette smoke, air pollutants, and infectious agents during pre- and post-natal periods. The first and simplest interaction between a gene and the environment is a candidate interaction of both a well known gene and environmental factor in a direct physical or chemical interaction such as between CD14 and endotoxin or between HLA and allergens. Several GWAS have found environmental interactions with occupational asthma, aspirin exacerbated respiratory disease, tobacco smoke-related airway dysfunction, and farm-related atopic diseases. As one of the mechanisms behind gene-environment interaction is epigenetics, a few studies on DNA CpG methylation have been reported on subphenotypes of asthma, pitching the exciting idea that it may be possible to intervene at the junction between the genome and the environment. Epigenetic studies are starting to include data from clinical samples, which will make them another powerful tool for re-search on gene-environment interactions in asthma.
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Affiliation(s)
- Jong-Uk Lee
- Department of Interdisciplinary Program in Biomedical Science Major, Soonchunhyang Graduate School, Bucheon, Korea
| | - Jeong Dong Kim
- Department of Interdisciplinary Program in Biomedical Science Major, Soonchunhyang Graduate School, Bucheon, Korea
| | - Choon-Sik Park
- Genome Research Center and Division of Allergy and Respiratory Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea.
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