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Beerweiler CC, Salvermoser M, Theodorou J, Böck A, Sattler F, Kulig P, Tosevski V, Schaub B. Farm-dust mediated protection of childhood asthma: Mass cytometry reveals novel cellular regulation. Allergy 2024. [PMID: 39400913 DOI: 10.1111/all.16347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 08/06/2024] [Accepted: 08/20/2024] [Indexed: 10/15/2024]
Abstract
BACKGROUND Farm-dust mediated asthma protection in childhood was replicated in numerous epidemiological studies. Central immune mechanisms are not fully understood. This exploratory study aimed to disentangle underlying immunological regulation of farm-dust mediated protection in peripheral blood on a single-cell level. METHODS Single-cell protein expression of in vitro farm-dust stimulated and unstimulated cells from allergic asthmatics and healthy controls were measured using mass cytometry. Analysis of innate and adaptive cellular proportions (linear regression) and T-cell proliferation was performed. Functional marker intensity was investigated using Earth Mover's Distance and the Monte Carlo permutation test. RESULTS Farm-dust stimulation induced cell type-specific regulation: Key-features of farm-dust stimulation comprised opposing regulation of immune-cell frequencies (downregulated innate cell populations (monocytes/DCs (p < .001), NK-cells (p < .05)) and upregulated adaptive populations (B-cells, CD4+ T-cells (both p < .05)), reduced CD4+ CD25- T-cell proliferation, and differential cell type-specific functional marker expression. Following stimulation, functional marker analysis revealed induced activation (CD25) in T-cells and NK-T-cells in both phenotypes even after correction for multiple testing. Cytotoxicity (GZMB) and inflammation (pERK1/2, pp38) related markers were reduced in T-cells exclusively in asthmatic children. Asthma-associated markers (Gata3, RORγ, and HLA-DR) were reduced in T- and innate- cell populations of asthmatics following stimulation. B-cells displayed a phenotypically independent increase of diverse functional markers upon farm-dust stimulation. CONCLUSIONS This study mimicking in vivo environmental exposure identified a novel profile of immune-regulatory markers using mass cytometry demonstrating decreased asthma-associated markers following farm-dust stimulation. These findings may be key for further studies on asthma prevention in childhood.
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Affiliation(s)
- Claudia Carina Beerweiler
- Department of Pediatrics, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
- Member of German Center for Lung Research - DZL, LMU Munich, Munich, Germany
| | - Michael Salvermoser
- Department of Pediatrics, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
| | - Johanna Theodorou
- Department of Pediatrics, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
- Member of German Center for Lung Research - DZL, LMU Munich, Munich, Germany
| | - Andreas Böck
- Department of Pediatrics, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
- Member of German Center for Child and Adolescent Health-DZKJ, LMU, Munich, Germany
| | - Franziska Sattler
- Department of Pediatrics, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
| | - Paulina Kulig
- Mass Cytometry Facility, University of Zurich, Zurich, Switzerland
| | - Vinko Tosevski
- Mass Cytometry Facility, University of Zurich, Zurich, Switzerland
| | - Bianca Schaub
- Department of Pediatrics, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
- Member of German Center for Lung Research - DZL, LMU Munich, Munich, Germany
- Member of German Center for Child and Adolescent Health-DZKJ, LMU, Munich, Germany
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2
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Laubhahn K, Schaub B. From preschool wheezing to asthma: Immunological determinants. Pediatr Allergy Immunol 2023; 34:e14038. [PMID: 37877843 DOI: 10.1111/pai.14038] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 09/29/2023] [Accepted: 10/10/2023] [Indexed: 10/26/2023]
Abstract
Asthma represents a chronic respiratory disease affecting millions of children worldwide. The transition from preschool wheezing to school-age asthma involves a multifaceted interplay of various factors, including immunological aspects in early childhood. These factors include complex cellular interactions among different immune cell subsets, induction of pro-inflammatory mediators and the molecular impact of environmental factors like allergens or viral infections on the developing immune system. Furthermore, the activation of specific genes and signalling pathways during this early phase plays a pivotal role in the manifestation of symptoms and subsequent development of asthma. Early identification of the propensity or risk for asthma development, for example by allergen sensitisation and viral infections during this critical period, is crucial for understanding the transition from wheeze to asthma. Favourable immune regulation during a critical 'window of opportunity' in early childhood can induce persistent changes in immune cell behaviour. In this context, trained immunity, including memory function of innate immune cells, has significant implications for understanding immune responses, potentially shaping long-term immunological outcomes based on early-life environmental exposures. Exploration of these underlying immune mechanisms that drive disease progression will provide valuable insights to understand childhood asthma development. This will be instrumental to develop preventive strategies at different stages of disease development for (i) inhibiting progression from wheeze to asthma or (ii) reducing disease severity and (iii) uncovering novel therapeutic strategies and contributing to more tailored and effective treatments for childhood asthma. In the long term, this shall empower healthcare professionals to develop evidence-based interventions that reduce the burden of asthma for children, families and society overall.
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Affiliation(s)
- Kristina Laubhahn
- Department of Pulmonary and Allergy, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
- Member of German Centre for Lung Research - DZL, LMU Munich, Munich, Germany
| | - Bianca Schaub
- Department of Pulmonary and Allergy, Dr. von Hauner Children's Hospital, LMU University Hospital, LMU Munich, Munich, Germany
- Member of German Centre for Lung Research - DZL, LMU Munich, Munich, Germany
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3
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What Have Mechanistic Studies Taught Us About Childhood Asthma? THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY. IN PRACTICE 2023; 11:684-692. [PMID: 36649800 DOI: 10.1016/j.jaip.2023.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/15/2023]
Abstract
Childhood asthma is a chronic heterogeneous syndrome consisting of different disease entities or phenotypes. The immunologic and cellular processes that occur during asthma development are still not fully understood but represent distinct endotypes. Mechanistic studies have examined the role of gene expression, protein levels, and cell types in early life development and the manifestation of asthma, many under the influence of environmental stimuli, which can be both protective and risk factors for asthma. Genetic variants can regulate gene expression, controlled partly by different epigenetic mechanisms. In addition, environmental factors, such as living space, nutrition, and smoking, can contribute to these mechanisms. All of these factors produce modifications in gene expression that can alter the development and function of immune and epithelial cells and subsequently different trajectories of childhood asthma. These early changes in a partially immature immune system can have dramatic effects (e.g., causing dysregulation), which in turn contribute to different disease endotypes and may help to explain differential responsiveness to asthma treatment. In this review, we summarize published studies that have aimed to uncover distinct mechanisms in childhood asthma, considering genetics, epigenetics, and environment. Moreover, a discussion of new, powerful tools for single-cell immunologic assays for phenotypic and functional analysis is included, which promise new mechanistic insights into childhood asthma development and therapeutic and preventive strategies.
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4
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Theodorou J, Nowak E, Böck A, Salvermoser M, Beerweiler C, Zeber K, Kulig P, Tsang MS, Wong CK, Wong GWK, Roponen M, Kumbrink J, Alhamdan F, Michel F, Garn H, Tosevski V, Schaub B. Mitogen-activated protein kinase signaling in childhood asthma development and environment-mediated protection. Pediatr Allergy Immunol 2022; 33:e13657. [PMID: 34455626 DOI: 10.1111/pai.13657] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/14/2021] [Accepted: 08/19/2021] [Indexed: 01/06/2023]
Abstract
BACKGROUND While childhood asthma prevalence is rising in Westernized countries, farm children are protected. The mitogen-activated protein kinase (MAPK) pathway with its negative regulator dual-specificity phosphatase-1 (DUSP1) is presumably associated with asthma development. OBJECTIVES We aimed to investigate the role of MAPK signaling in childhood asthma and its environment-mediated protection, including a representative selection of 232 out of 1062 children from two cross-sectional cohorts and one birth cohort study. METHODS Peripheral blood mononuclear cells (PBMC) from asthmatic and healthy children were cultured upon stimulation with farm-dust extracts or lipopolysaccharide. In subgroups, gene expression was analyzed by qPCR (PBMCs, cord blood) and NanoString technology (dendritic cells). Protein expression of phosphorylated MAPKs was measured by mass cytometry. Histone acetylation was investigated by chromatin immunoprecipitation. RESULTS Asthmatic children expressed significantly less DUSP1 (p = .006) with reduced acetylation at histone H4 (p = .012) compared with healthy controls. Farm-dust stimulation upregulated DUSP1 expression reaching healthy levels and downregulated inflammatory MAPKs on gene and protein levels (PBMCs; p ≤ .01). Single-cell protein analysis revealed downregulated pMAPKs upon farm-dust stimulation in B cells, NK cells, monocytes, and T-cell subpopulations. CONCLUSION Lower DUSP1 baseline levels in asthmatic children and anti-inflammatory regulation of MAPK in several immune cell types by farm-dust stimulation indicate a regulatory function for DUSP1 for future therapy contributing to anti-inflammatory characteristics of farming environments.
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Affiliation(s)
- Johanna Theodorou
- Pediatric Allergology, Department of Pediatrics, Dr. von Hauner Children´s Hospital, University Hospital, LMU Munich, Munich, Germany.,Member of German Center for Lung Research - DZL, LMU Munich, Munich, Germany
| | - Elisabeth Nowak
- Pediatric Allergology, Department of Pediatrics, Dr. von Hauner Children´s Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Andreas Böck
- Pediatric Allergology, Department of Pediatrics, Dr. von Hauner Children´s Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Michael Salvermoser
- Pediatric Allergology, Department of Pediatrics, Dr. von Hauner Children´s Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Claudia Beerweiler
- Pediatric Allergology, Department of Pediatrics, Dr. von Hauner Children´s Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Kathrin Zeber
- Pediatric Allergology, Department of Pediatrics, Dr. von Hauner Children´s Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Paulina Kulig
- Mass Cytometry Facility, University of Zurich, Zurich, Switzerland
| | - Miranda S Tsang
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China
| | - Chun-Kwok Wong
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China
| | - Gary W K Wong
- Department of Pediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
| | - Marjut Roponen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jörg Kumbrink
- Institute of Pathology, Medical Faculty, LMU Munich, Munich, Germany.,German Cancer Consortium (DKTK), Partner site Munich, Munich, Germany
| | - Fahd Alhamdan
- Institute of Laboratory Medicine and Pathobiochemistry, Molecular Diagnostics, Philipps University Marburg, Marburg, Germany
| | - Florian Michel
- Institute of Laboratory Medicine and Pathobiochemistry, Molecular Diagnostics, Philipps University Marburg, Marburg, Germany
| | - Holger Garn
- Institute of Laboratory Medicine and Pathobiochemistry, Molecular Diagnostics, Philipps University Marburg, Marburg, Germany
| | - Vinko Tosevski
- Mass Cytometry Facility, University of Zurich, Zurich, Switzerland
| | - Bianca Schaub
- Pediatric Allergology, Department of Pediatrics, Dr. von Hauner Children´s Hospital, University Hospital, LMU Munich, Munich, Germany.,Member of German Center for Lung Research - DZL, LMU Munich, Munich, Germany
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5
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Role of early life immune regulation in asthma development. Semin Immunopathol 2019; 42:29-42. [PMID: 31873782 PMCID: PMC7079989 DOI: 10.1007/s00281-019-00774-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 11/15/2019] [Indexed: 02/07/2023]
Abstract
Development of childhood asthma is complex with a strong interaction of genetic, epigenetic, and environmental factors. Ultimately, it is critical how the immune system of a child responds to these influences and whether effective strategies for a balanced and healthy immune maturation can be assured. Pregnancy and early childhood are particularly susceptible for exogenous influences due to the developing nature of a child’s immune system. While endogenous influences such as family history and the genetic background are immutable, epigenetic regulations can be modulated by both heredity and environmental exposures. Prenatal influences such as a mother’s nutrition, smoking, or infections influence the complex interplay of innate and adaptive immune regulation as well as peri- and postnatal influences including mode of delivery. Early in life, induction and continuous training of healthy maturation include balanced innate immunity (e.g., via innate lymphoid cells) and an equilibrium of T-cell subpopulations (e.g., via regulatory T cells) to counter-regulate potential pro-inflammatory or exuberant immune reactions. Later in childhood, rather compensatory immune mechanisms are required to modulate deviant regulation of a child’s already primed immune trajectory. The specific effects of exogenous and endogenous influences on a child’s maturing immune system are summarized in this review, and its importance and potential intervention for early prevention and treatment strategies are delineated.
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6
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Vuitton D, Divaret-Chauveau A, Dalphin ML, Laplante JJ, von Mutius E, Dalphin JC. Protection contre l’allergie par l’environnement de la ferme : en 15 ans, qu’avons-nous appris de la cohorte européenne « PASTURE » ? BULLETIN DE L'ACADÉMIE NATIONALE DE MÉDECINE 2019. [DOI: 10.1016/j.banm.2019.05.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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7
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Deckers J, Lambrecht BN, Hammad H. How a farming environment protects from atopy. Curr Opin Immunol 2019; 60:163-169. [PMID: 31499321 DOI: 10.1016/j.coi.2019.08.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 08/02/2019] [Indexed: 12/15/2022]
Abstract
It is now well established that the exposure to certain environments such as farms has the potential to protect from the development of allergies later in life. This protection is achieved when repeated exposure to the farming environment occurs early in life, but persists when children spend sufficient amount of time in contact with livestock and hay, and drink unpasteurized milk. The capacity of farm dust to protect from allergy development lies, amongst others, in the microbe composition in the farm. These protective microbes release various metabolites and cell wall components that change farmers' home dust composition, when compared to urbanized home dust. Additionally, they can colonize various barrier sites (skin, lung, intestine) in farmers' children, leading to persistent changes in the way their immune system and their barrier cells respond to environmental allergens.
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Affiliation(s)
- Julie Deckers
- Laboratory of Immunoregulation and Mucosal Immunology, VIB Center for Inflammation Research, Technologiepark-Zwijnaarde 71, B-9052 Ghent (Zwijnaarde), Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
| | - Bart N Lambrecht
- Laboratory of Immunoregulation and Mucosal Immunology, VIB Center for Inflammation Research, Technologiepark-Zwijnaarde 71, B-9052 Ghent (Zwijnaarde), Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium; Department of Respiratory Medicine, Erasmus Medical Center, Rotterdam, The Netherlands.
| | - Hamida Hammad
- Laboratory of Immunoregulation and Mucosal Immunology, VIB Center for Inflammation Research, Technologiepark-Zwijnaarde 71, B-9052 Ghent (Zwijnaarde), Belgium; Department of Internal Medicine and Pediatrics, Ghent University, Ghent, Belgium
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8
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Krusche J, Twardziok M, Rehbach K, Böck A, Tsang MS, Schröder PC, Kumbrink J, Kirchner T, Xing Y, Riedler J, Dalphin JC, Pekkanen J, Lauener R, Roponen M, Li J, Wong CK, Wong GWK, Schaub B. TNF-α-induced protein 3 is a key player in childhood asthma development and environment-mediated protection. J Allergy Clin Immunol 2019; 144:1684-1696.e12. [PMID: 31381928 DOI: 10.1016/j.jaci.2019.07.029] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 11/17/2022]
Abstract
BACKGROUND Childhood asthma prevalence is significantly greater in urban areas compared with rural/farm environments. Murine studies have shown that TNF-α-induced protein 3 (TNFAIP3; A20), an anti-inflammatory regulator of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, mediates environmentally induced asthma protection. OBJECTIVE We aimed to determine the role of TNFAIP3 for asthma development in childhood and the immunomodulatory effects of environmental factors. METHODS In a representative selection of 250 of 2168 children from 2 prospective birth cohorts and 2 cross-sectional studies, we analyzed blood cells of healthy and asthmatic children from urban and rural/farm environments from Europe and China. PBMCs were stimulated ex vivo with dust from "asthma-protective" farms or LPS. NF-κB signaling-related gene and protein expression was assessed in PBMCs and multiplex gene expression assays (NanoString Technologies) in isolated dendritic cells of schoolchildren and in cord blood mononuclear cells from newborns. RESULTS Anti-inflammatory TNFAIP3 gene and protein expression was consistently decreased, whereas proinflammatory Toll-like receptor 4 expression was increased in urban asthmatic patients (P < .05), reflecting their increased inflammatory status. Ex vivo farm dust or LPS stimulation restored TNFAIP3 expression to healthy levels in asthmatic patients and shifted NF-κB signaling-associated gene expression toward an anti-inflammatory state (P < .001). Farm/rural children had lower expression, indicating tolerance induction by continuous environmental exposure. Newborns with asthma at school age had reduced TNFAIP3 expression at birth, suggesting TNFAIP3 as a possible biomarker predicting subsequent asthma. CONCLUSION Our data indicate TNFAIP3 as a key regulator during childhood asthma development and its environmentally mediated protection. Because environmental dust exposure conferred the anti-inflammatory effects, it might represent a promising future agent for asthma prevention and treatment.
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Affiliation(s)
- Johanna Krusche
- Pediatric Allergology, Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany; Member of the German Center for Lung Research-DZL, LMU Munich, Munich, Germany
| | - Monika Twardziok
- Pediatric Allergology, Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Katharina Rehbach
- Pediatric Allergology, Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Andreas Böck
- Pediatric Allergology, Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Miranda S Tsang
- Institute of Chinese Medicine, Chinese University of Hong Kong, Hong Kong, China
| | - Paul C Schröder
- Pediatric Allergology, Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany
| | - Jörg Kumbrink
- Institute of Pathology, Medical Faculty, LMU Munich, Munich, Germany; German Cancer Consortium (DKTK), Partner Site Munich, Munich, Germany
| | - Thomas Kirchner
- Institute of Pathology, Medical Faculty, LMU Munich, Munich, Germany; German Cancer Consortium (DKTK), Partner Site Munich, Munich, Germany
| | - Yuhan Xing
- Department of Paediatrics, Faculty of Medicine, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, N.T., Hong Kong, China
| | - Josef Riedler
- Children's Hospital Schwarzach, Schwarzach, Austria, Teaching Hospital of Paracelsus Medical Private University Salzburg, Salzburg, Austria
| | - Jean-Charles Dalphin
- University Hospital of Besançon, UMR CNRS 6249 Chrono-Environment, University of Franche-Comté, Besançon, France
| | - Juha Pekkanen
- Department of Health Security, National Institute for Health and Welfare (THL), Kuopio, Finland; Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Roger Lauener
- Children's Hospital of Eastern Switzerland, St Gallen, Switzerland; University of Zurich, Zurich, Switzerland; School of Medicine, University of St Gallen, St Gallen, Switzerland; Christine Kühne-Center for Allergy Care and Education, CK-CARE, Davos, Switzerland
| | - Marjut Roponen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jing Li
- Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Department of Allergy and Clinical Immunology, Guangzhou, China
| | - Chun K Wong
- Department of Chemical Pathology, Chinese University of Hong Kong, Shatin, NT, Hong Kong, China
| | - Gary W K Wong
- Department of Paediatrics, Faculty of Medicine, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, N.T., Hong Kong, China.
| | - Bianca Schaub
- Pediatric Allergology, Department of Pediatrics, Dr von Hauner Children's Hospital, University Hospital, LMU Munich, Munich, Germany; Member of the German Center for Lung Research-DZL, LMU Munich, Munich, Germany.
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9
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Zhang Y, Ye B, Zheng H, Zhang W, Han L, Yuan P, Zhang C. Association Between Organic Dust Exposure and Adult-Asthma: A Systematic Review and Meta-Analysis of Case-Control Studies. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2019; 11:818-829. [PMID: 31552717 PMCID: PMC6761076 DOI: 10.4168/aair.2019.11.6.818] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 09/10/2018] [Accepted: 09/13/2018] [Indexed: 12/25/2022]
Abstract
Background Exposure to organic dust has been widely investigated as a potential risk factor for asthma with different results. To clarify a potential relationship, we performed the present meta-analysis to integrate the results of studies examining the association of organic dust exposure with asthma. Methods A comprehensive literature search in the electronic databases including EMBASE, PubMed and Cochrane Library databases (up to August 2018) was conducted. The adjusted odds ratios (ORs) with corresponding 95% confidence interval (CI) for organic dust exposure and asthma were retrieved and pooled to generate summary effect estimates in Revman 5.2. Results Database searches retrieved 1,016 records. A total of 17 studies containing 3,619 cases and 6,585 controls were finally included in our meta-analysis. The summary estimates suggested that organic dust exposure was positively associated with asthma (OR, 1.48; 95% CI, 1.26–1.75; P < 0.00001), whether among population-based case-control studies (OR, 1.24; 95% CI, 1.13–1.35; P < 0.00001) or hospital-based case-control studies (OR, 2.79; 95% CI, 1.27–6.12; P = 0.01). Subgroup analysis showed that paper/wood (OR, 1.62; 95% CI, 1.38–1.90; P < 0.00001), flour/grain (OR, 1.48; 95% CI, 1.11–1.97; P = 0.008), and textile dust (OR, 1.50; 95% CI, 1.08–2.09; P = 0.02) exposure were significantly associated with asthma. Conclusions Based on the studies evaluated, our meta-analysis results prompt that organic dust exposure is a risk factor inducing asthma, although precise analysis focus on specific organic dust materials is still warranted.
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Affiliation(s)
- Yan Zhang
- Department of Emergency, Jinan Children's Hospital, Qilu Children's Hospital of Shandong University, Jinan 250022, China.
| | - Bing Ye
- Department of Emergency, Jinan Children's Hospital, Qilu Children's Hospital of Shandong University, Jinan 250022, China
| | - Hongling Zheng
- Department of Emergency, Jinan Children's Hospital, Qilu Children's Hospital of Shandong University, Jinan 250022, China
| | - Wei Zhang
- Department of Emergency, Jinan Children's Hospital, Qilu Children's Hospital of Shandong University, Jinan 250022, China
| | - Lin Han
- Department of Emergency, Jinan Children's Hospital, Qilu Children's Hospital of Shandong University, Jinan 250022, China
| | - Peng Yuan
- Department of Emergency, Jinan Children's Hospital, Qilu Children's Hospital of Shandong University, Jinan 250022, China
| | - Chao Zhang
- Department of Emergency, Jinan Children's Hospital, Qilu Children's Hospital of Shandong University, Jinan 250022, China
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10
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Martikainen MV, Rönkkö TJ, Schaub B, Täubel M, Gu C, Wong GW, Li J, Pekkanen J, Komppula M, Hirvonen MR, Jalava PI, Roponen M. Integrating farm and air pollution studies in search for immunoregulatory mechanisms operating in protective and high-risk environments. Pediatr Allergy Immunol 2018; 29:815-822. [PMID: 30152886 DOI: 10.1111/pai.12975] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 08/15/2018] [Accepted: 08/15/2018] [Indexed: 01/09/2023]
Abstract
BACKGROUND Studies conducted in farm environments suggest that diverse microbial exposure promotes children's lung health. The underlying mechanisms are unclear, and the development of asthma-preventive strategies has been delayed. More comprehensive investigation of the environment-induced immunoregulation is required for better understanding of asthma pathogenesis and prevention. Exposure to air pollution, including particulate matter (PM), is a risk factor for asthma, thus providing an excellent counterpoint for the farm-effect research. Lack of comparable data, however, complicates interpretation of the existing information. We aimed to explore the immunoregulatory effects of cattle farm dust (protective, Finland) and urban air PM (high-risk, China) for the first time using identical research methods. METHODS We stimulated PBMCs of 4-year-old children (N = 18) with farm dust and size-segregated PM and assessed the expression of immune receptors CD80 and ILT4 on dendritic cells and monocytes as well as cytokine production of PBMCs. Environmental samples were analysed for their composition. RESULTS Farm dust increased the percentage of cells expressing CD80 and the cytokine production of children's immune cells, whereas PM inhibited the expression of important receptors and the production of soluble mediators. Although PM samples induced parallel immune reactions, the size-fraction determined the strength of the effects. CONCLUSIONS Our study demonstrates the significance of using the same research framework when disentangling shared and distinctive immune pathways operating in different environments. Observed stimulatory effects of farm dust and inhibitory effects of PM could shape responses towards respiratory pathogens and allergens, and partly explain differences in asthma prevalence between studied environments.
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Affiliation(s)
- Maria-Viola Martikainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Teemu J Rönkkö
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Bianca Schaub
- Department of Allergy and Pulmonology, University Children's Hospital, Dr. von Hauner Children's Hospital, LMU Munich, Munich, Germany.,Member of the German Center for Lung Research (DZL), Munich, Germany
| | - Martin Täubel
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland
| | - Cheng Gu
- School of the Environment, Nanjing University, Nanjing, China
| | - Gary Wk Wong
- Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
| | - Jing Li
- Department of Allergy and Clinical Immunology, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Juha Pekkanen
- Environmental Health Unit, National Institute for Health and Welfare, Kuopio, Finland.,Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Mika Komppula
- Atmospheric Research Centre of Eastern Finland, Finnish Meteorological Institute, Kuopio, Finland
| | - Maija-Riitta Hirvonen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Pasi I Jalava
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Marjut Roponen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
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11
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Mazur A, Szylling A, Bielecka T, Strzelak A, Kulus M. Is the "farm effect" hypothesis still current? Atopy and allergic diseases in rural and urban children in Poland. J Asthma 2017; 55:1147-1155. [PMID: 29211564 DOI: 10.1080/02770903.2017.1400046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The prevalence of allergic diseases has reached epidemic proportions in the Western world. Although farm-living has been associated with a lower prevalence of asthma and atopy, a marked increase in atopy among rural populations after accession to the European Union has been recently reported in Poland. Here, we aimed to investigate the effect of living environment on the prevalence of atopy and allergic diseases in Polish children. METHODS 400 schoolchildren aged 10-14 years from the capital city (223) and from traditional rural part of the country (177) were recruited from June to November 2011. Data on allergic diseases and symptoms were collected by means of questionnaire and physical examination. Atopy was assessed based on skin prick tests (SPTs) reactivity to inhalant allergens in 350 children. RESULTS A high discrepancy between the prevalence of allergic symptoms (46.7%) and doctor-diagnosed allergic diseases (25%) was demonstrated (p < 0.0001). Urban children had a higher overall prevalence of allergic diseases and atopy than children living in rural areas, 29.3% versus 17.1% (p = 0.007) and 33.5% versus 20% (p = 0.0045), respectively. However, no significant differences in the rates of particular allergic diseases were noted (p > 0.05). There was higher SPT positivity to trees, grass, corn, weeds, animal dander, and molds in urban children (p < 0.05). CONCLUSIONS Our data support the protective effect of farm-living on the prevalence of atopy and overall allergic diseases, albeit not on particular allergic diseases, in children in Poland. The underlying mechanisms are not identified, but current socioeconomic changes may be responsible.
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Affiliation(s)
- Agnieszka Mazur
- a Department of Pediatric Pulmonology and Allergy , Medical University of Warsaw , Warsaw , Poland
| | - Anna Szylling
- b Department of Prevention of Environmental Hazards and Allergology , Medical University of Warsaw , Warsaw , Poland
| | - Teresa Bielecka
- a Department of Pediatric Pulmonology and Allergy , Medical University of Warsaw , Warsaw , Poland
| | - Agnieszka Strzelak
- a Department of Pediatric Pulmonology and Allergy , Medical University of Warsaw , Warsaw , Poland
| | - Marek Kulus
- a Department of Pediatric Pulmonology and Allergy , Medical University of Warsaw , Warsaw , Poland
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12
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Twardziok M, Schröder PC, Krusche J, Casaca VI, Illi S, Böck A, Loss GJ, Kabesch M, Toncheva AA, Roduit C, Depner M, Genuneit J, Renz H, Roponen M, Weber J, Braun-Fahrländer C, Riedler J, Lauener R, Vuitton DA, Dalphin JC, Pekkanen J, von Mutius E, Schaub B, Hyvärinen A, Karvonen AM, Kirjavainen PV, Remes S, Kaulek V, Dalphin ML, Ege M, Pfefferle PI, Doekes G. Asthmatic farm children show increased CD3 +CD8 low T-cells compared to non-asthmatic farm children. Clin Immunol 2017; 183:285-292. [PMID: 28917722 DOI: 10.1016/j.clim.2017.09.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 07/28/2017] [Accepted: 09/12/2017] [Indexed: 11/15/2022]
Affiliation(s)
- Monika Twardziok
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany
| | - Paul C Schröder
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany
| | - Johanna Krusche
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany; Member of German Center for Lung Research, DZL, LMU Munich, Germany
| | - Vera I Casaca
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany
| | - Sabina Illi
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany
| | - Andreas Böck
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany
| | - Georg J Loss
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany; University of California, San Diego, School of Medicine, Department of Pediatrics, CA, USA
| | - Michael Kabesch
- Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany
| | - Antoaneta A Toncheva
- Department of Pediatric Pneumology and Allergy, University Children's Hospital Regensburg (KUNO), Regensburg, Germany
| | - Caroline Roduit
- Zurich University Children's Hospital, Zurich, Switzerland; Children's Hospital of Eastern Switzerland, St. Gallen, Switzerland and Christine Kühne-Center for Allergy Research and Education, St. Gallen, Switzerland
| | - Martin Depner
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany
| | - Jon Genuneit
- Institute of Epidemiology and Medical Biometry, Ulm University, Ulm, Germany
| | - Harald Renz
- Institute of Laboratory Medicine, Philipps University Marburg, Marburg, Germany; Member of German Center for Lung Research, DZL, LMU Munich, Germany
| | - Marjut Roponen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Juliane Weber
- Bavarian Health and Food Safety Authority, Oberschleißheim, Germany
| | | | | | - Roger Lauener
- Children's Hospital of Eastern Switzerland, St. Gallen, Switzerland and Christine Kühne-Center for Allergy Research and Education, St. Gallen, Switzerland
| | | | | | - Juha Pekkanen
- Department of Public health, University of Helsinki, Helsinki, Finland; Department of Health Security, National Institute for Health and Welfare, Kuopio, Finland
| | - Erika von Mutius
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany; Member of German Center for Lung Research, DZL, LMU Munich, Germany
| | - Bianca Schaub
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany; Member of German Center for Lung Research, DZL, LMU Munich, Germany.
| | | | - Anne Hyvärinen
- Department of Health Security, National Institute for Health and Welfare, Kuopio, Finland
| | - Anne M Karvonen
- Department of Health Security, National Institute for Health and Welfare, Kuopio, Finland
| | - Pirkka V Kirjavainen
- Department of Health Security, National Institute for Health and Welfare, Kuopio, Finland
| | - Sami Remes
- Kuopio University Hospital, Department of Paediatrics, Kuopio, Finland
| | - Vincent Kaulek
- University Hospital of Besançon, University of Franche-Comté, Besançon, France
| | - Marie-Laure Dalphin
- University Hospital of Besançon, University of Franche-Comté, Besançon, France
| | - Markus Ege
- Dr. von Hauner Children's Hospital, Ludwig Maximilians University Munich, Munich, Germany; Member of German Center for Lung Research, DZL, LMU Munich, Germany
| | - Petra I Pfefferle
- Institute of Laboratory Medicine, Philipps University Marburg, Marburg, Germany; Member of German Center for Lung Research, DZL, LMU Munich, Germany
| | - Gert Doekes
- Utrecht University, Institut for Risk Assessment Sciences (IRAS), Devision of Environmental Epidemiology, Utrecht, Netherlands
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13
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Georgountzou A, Papadopoulos NG. Postnatal Innate Immune Development: From Birth to Adulthood. Front Immunol 2017; 8:957. [PMID: 28848557 PMCID: PMC5554489 DOI: 10.3389/fimmu.2017.00957] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/26/2017] [Indexed: 12/20/2022] Open
Abstract
It is well established that adaptive immune responses are deficient in early life, contributing to increased mortality and morbidity. The developmental trajectories of different components of innate immunity are only recently being explored. Individual molecules, cells, or pathways of innate recognition and signaling, within different compartments/anatomical sites, demonstrate variable maturation patterns. Despite some discrepancies among published data, valuable information is emerging, showing that the developmental pattern of cytokine responses during early life is age and toll-like receptor specific, and may be modified by genetic and environmental factors. Interestingly, specific environmental exposures have been linked both to innate function modifications and the occurrence of chronic inflammatory disorders, such as respiratory allergies. As these conditions are on the rise, our knowledge on innate immune development and its modulating factors needs to be expanded. Improved understanding of the sequence of events associated with disease onset and persistence will lead toward meaningful interventions. This review describes the state-of-the-art on normal postnatal innate immune ontogeny and highlights research areas that are currently explored or should be further addressed.
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Affiliation(s)
- Anastasia Georgountzou
- Allergy and Clinical Immunology Unit, 2nd Pediatric Clinic, National and Kapodistrian University of Athens, Athens, Greece
| | - Nikolaos G Papadopoulos
- Allergy and Clinical Immunology Unit, 2nd Pediatric Clinic, National and Kapodistrian University of Athens, Athens, Greece.,Division of Infection, Inflammation and Respiratory Medicine, The University of Manchester, Manchester, United Kingdom
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14
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Vroman H, Hendriks RW, Kool M. Dendritic Cell Subsets in Asthma: Impaired Tolerance or Exaggerated Inflammation? Front Immunol 2017; 8:941. [PMID: 28848549 PMCID: PMC5552666 DOI: 10.3389/fimmu.2017.00941] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/24/2017] [Indexed: 12/14/2022] Open
Abstract
Asthma is a prevalent chronic heterogeneous inflammatory disease of the airways, leading to reversible airway obstruction, in which various inflammatory responses can be observed. Mild to moderate asthma patients often present with a Th2-mediated eosinophilic inflammation whereas in severe asthma patients, a Th17-associated neutrophilic or combined Th2 and Th17-mediated eosinophilic/neutrophilic inflammation is observed. The differentiation of these effector Th2 and Th17-cells is induced by allergen-exposed dendritic cells (DCs) that migrate toward the lung draining lymph node. The DC lineage comprises conventional DCs (cDCs) and plasmacytoid DCs (pDCs), of which the cDC lineage consists of type 1 cDCs (cDC1s) and cDC2s. During inflammation, also monocytes can differentiate into so-called monocyte-derived DCs (moDCs). These DC subsets differ both in ontogeny, localization, and in their functional properties. New identification tools and the availability of transgenic mice targeting specific DC subsets enable the investigation of how these different DC subsets contribute to or suppress asthma pathogenesis. In this review, we will discuss mechanisms used by different DC subsets to elicit or hamper the pathogenesis of both Th2-mediated eosinophilic asthma and more severe Th17-mediated neutrophilic inflammation.
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Affiliation(s)
- Heleen Vroman
- Department of Pulmonary Medicine, Erasmus MC, Rotterdam, Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC, Rotterdam, Netherlands
| | - Mirjam Kool
- Department of Pulmonary Medicine, Erasmus MC, Rotterdam, Netherlands
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15
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Marfortt DA, Josviack D, Lozano A, Cuestas E, Agüero L, Castro-Rodriguez JA. Differences between preschoolers with asthma and allergies in urban and rural environments. J Asthma 2017; 55:470-476. [PMID: 28605217 DOI: 10.1080/02770903.2017.1339800] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVE Previous studies have provided conflicting results about how living in a rural or urban environment influences schoolchildren with asthma and allergic diseases in different ways. The aim of the present study was to evaluate if recurrent wheezing preschoolers from rural or urban areas differ in asthma, allergic diseases, and atopy. METHODS A cross-sectional-study in Rafaela, Argentina, on 143 preschoolers with recurrent wheezing from rural and urban settings was performed (2010-2012). Diagnosis of asthma (by positive asthma predictive index [API]), allergic diseases (rhinitis, dermatitis), and atopy (by skin prick test [SPT], peripheral blood eosinophils, and serum total IgE) were assessed. RESULTS Preschoolers from rural settings had significantly higher prevalence of vaginal delivery, longer breastfeeding, earlier onset of wheezing, more parental smoking, siblings, shared a bedroom, and more exposure to chemicals used in plant fumigation or farm animals, and unpasteurized milk consumption, in comparison to preschoolers living in urban setting. In contrast, preschoolers from urban areas had significantly higher prevalence of parental history of allergy, positive skin prick test, and positive API. After multivariate analysis adjusting for covariates, maternal smoking [odds ratio (OR) = 3.44] and positive SPT (OR = 5.57) significantly increase the risk of asthma diagnosis (positive API); in contrast, living in rural setting (OR = 0.04), and having more siblings (OR = 0.51) decrease their risk. CONCLUSIONS Recurrent wheezing preschoolers from rural areas had a significant inverse odds of being diagnosed with asthma (type-2 inflammation) when compared to those from urban areas. Exposure to farm animals and consumption of unpasteurized milk might have a role.
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Affiliation(s)
- Daniel A Marfortt
- a Institute of Child Respiratory Medicine , Rafaela , Santa Fe , Argentina
| | - Dario Josviack
- a Institute of Child Respiratory Medicine , Rafaela , Santa Fe , Argentina
| | - Alejandro Lozano
- b Division of Allergy and Inmunology , Clínica Universitaria Reina Fabiola, Universidad Católica de Cordoba , Cordoba , Argentina
| | - Eduardo Cuestas
- c Department of Statistcs and Pediatrics, Facultad de Medicina , Universidad Católica de Cordoba , Cordoba , Argentina
| | - Luis Agüero
- d Department of Pulmonology , Children's Hospital Notti , Mendoza , Argentina
| | - Jose A Castro-Rodriguez
- e Division of Pediatrics, Department of Pediatric Cardiology and Respiratory, School of Medicine , Pontificia Universidad Católica de Chile , Santiago , Chile
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16
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Han YY, Badellino HA, Forno E, Celedón JC. Rural residence, farming environment, and allergic diseases in Argentinean adolescents. Pediatr Pulmonol 2017; 52:21-28. [PMID: 27377679 PMCID: PMC5177519 DOI: 10.1002/ppul.23511] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 06/06/2016] [Accepted: 06/10/2016] [Indexed: 01/17/2023]
Abstract
RATIONALE Little is known about residence in a rural or farming environment and allergic diseases in Latin America. METHODS Cross-sectional study of rural residence and current wheeze, current asthma and current symptoms of allergic rhino-conjunctivitis in 1,804 adolescents (ages 13-14 years) attending 31 schools in urban and rural areas of San Francisco (Córdoba, Argentina). Rural residence was classified as never, previous, and current. Duration of rural residence was categorized as 0, >0 but ≤5 years, and >5 years. Current wheeze, current asthma, and current allergic rhino-conjunctivitis were defined on the basis of responses to an extensively validated questionnaire from the International Study of Asthma and Allergies in Childhood. Logistic regression was used for the multivariable analysis of rural residence and the outcomes of interest. RESULTS After adjustment for current smoking and other covariates, current rural residence (odds ratio [OR] = 0.15, 95% confidence interval [CI] = 0.03-0.81) and rural residence for >5 years (OR = 0.32, 95%CI = 0.12-0.84) were significantly associated with reduced odds of current wheeze. In a multivariable analysis, current residence in a rural area (OR = 0.52, 95%CI = 0.32-0.86) and rural residence for >5 years (OR = 0.44, 95%CI = 0.26-0.73) were significantly associated with reduced odds of allergic rhino-conjunctivitis. This association was no longer significant after additional adjustment for current residence in a dairy farm, which was significantly associated with reduced odds of allergic rhino-conjunctivitis. Similarly, current regular contact with farm animals was significantly associated with reduced odds of allergic rhino-conjunctivitis. CONCLUSIONS Among Argentinean adolescents, current rural residence and rural residence for >5 years were associated with reduced odds of current wheeze and allergic rhino-conjunctivitis. These potential protective effects may be explained by a dairy farm environment, including regular contact with farm animals. Pediatr Pulmonol. 2017;52:21-28. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Yueh-Ying Han
- Division of Pediatric Pulmonary Medicine, Allergy, and Immunology, Children’s Hospital of Pittsburgh of UPMC, University of Pittsburgh, Pittsburgh, PA
| | - Héctor A. Badellino
- Department of Pediatric Respiratory Medicine, Regional Eastern Clinic, San Francisco (Córdoba Argentina)
| | - Erick Forno
- Division of Pediatric Pulmonary Medicine, Allergy, and Immunology, Children’s Hospital of Pittsburgh of UPMC, University of Pittsburgh, Pittsburgh, PA
| | - Juan C. Celedón
- Division of Pediatric Pulmonary Medicine, Allergy, and Immunology, Children’s Hospital of Pittsburgh of UPMC, University of Pittsburgh, Pittsburgh, PA
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