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Castillo F, Mora AM, Kayser GL, Vanos J, Hyland C, Yang AR, Eskenazi B. Environmental Health Threats to Latino Migrant Farmworkers. Annu Rev Public Health 2021; 42:257-276. [PMID: 33395542 PMCID: PMC8168948 DOI: 10.1146/annurev-publhealth-012420-105014] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Approximately 75% of farmworkers in the United States are Latino migrants, and about 50% of hired farmworkers do not have authorization to work in the United States. Farmworkers face numerous chemical, physical, and biological threats to their health. The adverse effects of these hazards may be amplified among Latino migrant farmworkers, who are concurrently exposed to various psychosocial stressors. Factors such as documentation status, potential lack of authorization to work in the United States, and language and cultural barriers may also prevent Latino migrants from accessing federal aid, legal assistance, and health programs. These environmental, occupational, and social hazards may further exacerbate existing health disparities among US Latinos. This population is also likely to be disproportionately impacted by emerging threats, including climate change and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Latino migrant farmworkers are essential to agriculture in the United States, and actions are needed to protect this vulnerable population.
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Affiliation(s)
- Federico Castillo
- Department of Environmental Science, Policy and Management, University of California, Berkeley, California 94720, USA;
| | - Ana M Mora
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, California 94720, USA; , ,
- Central American Institute for Studies on Toxic Substances (IRET), Universidad Nacional, Heredia 86-3000, Costa Rica
| | - Georgia L Kayser
- Health Sciences, University of California, San Diego, California 92093, USA; ,
| | - Jennifer Vanos
- School of Sustainability, Arizona State University, Tempe, Arizona 85287, USA;
| | - Carly Hyland
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, California 94720, USA; , ,
| | - Audrey R Yang
- Health Sciences, University of California, San Diego, California 92093, USA; ,
| | - Brenda Eskenazi
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, California 94720, USA; , ,
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Liebers V, Kendzia B, Stubel H, Borowitzki G, Gering V, Monsé C, Hagemeyer O, Merget R, Brüning T, Raulf M. Cell Activation and Cytokine Release Ex Vivo: Estimation of Reproducibility of the Whole-Blood Assay with Fresh Human Blood. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1108:25-36. [DOI: 10.1007/5584_2018_225] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Yoda Y, Tamura K, Shima M. Airborne endotoxin concentrations in indoor and outdoor particulate matter and their predictors in an urban city. INDOOR AIR 2017; 27:955-964. [PMID: 28161889 DOI: 10.1111/ina.12370] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/28/2017] [Indexed: 06/06/2023]
Abstract
Endotoxins are an important biological component of particulate matter and have been associated with adverse effects on human health. There have been some recent studies on airborne endotoxin concentrations. We collected fine (PM2.5 ) and coarse (PM10-2.5 ) particulate matter twice on weekdays and weekends each for 48 hour, inside and outside 55 homes in an urban city in Japan. Endotoxin concentrations in both fractions were measured using the kinetic Limulus Amebocyte Lysate assay. The relationships between endotoxin concentrations and household characteristics were evaluated for each fraction. Both indoor and outdoor endotoxin concentrations were higher in PM2.5 than in PM10-2.5 . In both PM2.5 and PM10-2.5 , indoor endotoxin concentrations were higher than outdoor concentrations, and the indoor endotoxin concentrations significantly correlated with outdoor concentrations in each fraction (R2 =0.458 and 0.198, respectively). Indoor endotoxin concentrations in PM2.5 were significantly higher in homes with tatami or carpet flooring and in homes with pets, and lower in homes that used air purifiers. Indoor endotoxin concentrations in PM10-2.5 were significantly higher in homes with two or more children and homes with tatami or carpet flooring. These results showed that the indoor endotoxin concentrations were associated with the household characteristics in addition to outdoor endotoxin concentrations.
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Affiliation(s)
- Y Yoda
- Department of Public Health, Hyogo College of Medicine, Nishinomiya, Japan
| | - K Tamura
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Japan
| | - M Shima
- Department of Public Health, Hyogo College of Medicine, Nishinomiya, Japan
- Hyogo Regional Center of Japan Environment and Children's Study, Hyogo College of Medicine, Nishinomiya, Japan
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Hoppe Parr KA, Hađina S, Kilburg-Basnyat B, Wang Y, Chavez D, Thorne PS, Weiss JP. Modification of sample processing for the Limulus amebocyte lysate assay enhances detection of inflammogenic endotoxin in intact bacteria and organic dust. Innate Immun 2017; 23:307-318. [PMID: 28359219 PMCID: PMC5814115 DOI: 10.1177/1753425917694084] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The pro-inflammatory potency and causal relationship with asthma of inhaled endotoxins have underscored the importance of accurately assessing the endotoxin content of organic dusts. The Limulus amebocyte lysate (LAL) assay has emerged as the preferred assay, but its ability to measure endotoxin in intact bacteria and organic dusts with similar sensitivity as purified endotoxin is unknown. We used metabolically radiolabeled Neisseria meningitidis and both rough and smooth Escherichia coli to compare dose-dependent activation in the LAL with purified endotoxin from these bacteria and shed outer membrane (OM) blebs. Labeled [14C]-3-OH-fatty acids were used to quantify the endotoxin content of the samples. Purified meningococcal and E. coli endotoxins and OM blebs displayed similar specific activity in the LAL assay to the purified LPS standard. In contrast, intact bacteria exhibited fivefold lower specific activity in the LAL assay but showed similar MD-2-dependent potency as purified endotoxin in inducing acute airway inflammation in mice. Pre-treatment of intact bacteria and organic dusts with 0.1 M Tris-HCl/10 mM EDTA increased by fivefold the release of endotoxin. These findings demonstrate that house dust and other organic dusts should be extracted with Tris/EDTA to more accurately assess the endotoxin content and pro-inflammatory potential of these environmental samples.
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Affiliation(s)
- Kimberly A. Hoppe Parr
- Department of Occupational & Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
| | - Suzana Hađina
- Department of Occupational & Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
| | - Brita Kilburg-Basnyat
- Department of Occupational & Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
| | - Yifang Wang
- Department of Occupational & Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
| | - Dulce Chavez
- Department of Occupational & Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
| | - Peter S. Thorne
- Department of Occupational & Environmental Health, The University of Iowa, Iowa City, IA 52242, USA
| | - Jerrold P. Weiss
- Departments of Internal Medicine and Microbiology and Inflammation Program, The University of Iowa, Iowa City, IA 52242, USA
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Bose S, Rivera-Mariani F, Chen R, Williams D, Belli A, Aloe C, McCormack MC, Breysse PN, Hansel NN. Domestic exposure to endotoxin and respiratory morbidity in former smokers with COPD. INDOOR AIR 2016; 26:734-42. [PMID: 26547489 PMCID: PMC5324735 DOI: 10.1111/ina.12264] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 10/31/2015] [Indexed: 05/28/2023]
Abstract
Indoor air pollution has been linked to adverse chronic obstructive pulmonary disease (COPD) health, but specific causative agents have not yet been identified. We evaluated the role of indoor endotoxin exposure upon respiratory health in former smokers with COPD. Eighty-four adults with moderate to severe COPD were followed longitudinally and indoor air and dust samples collected at baseline, 3 and 6 months. Respiratory outcomes were repeatedly assessed at each time point. The associations between endotoxin exposure in air and settled dust and health outcomes were explored using generalizing estimating equations in multivariate models accounting for confounders. Dust endotoxin concentrations in the main living area were highest in spring and lowest in fall, while airborne endotoxins remained steady across seasons. Airborne and dust endotoxin concentrations were weakly correlated with one another (rs = +0.24, P = 0.005). Endotoxin concentrations were not significantly associated with respiratory symptoms, rescue medication use, quality of life, or severe exacerbations. In vitro whole-blood assays of the pro-inflammatory capacity of PM10 filters with and without endotoxin depletion demonstrated that the endotoxin component of indoor air pollution was not the primary trigger for interleukin-1β release. Our findings support that endotoxin is not the major driver in the adverse effects of indoor PM upon COPD morbidity.
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Affiliation(s)
- S Bose
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA.
| | - F Rivera-Mariani
- Department of Biology, Miami Dade College Wolfson Campus, Miami, FL, USA
| | - R Chen
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - D Williams
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - A Belli
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - C Aloe
- Division of Pediatric Allergy and Immunology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - M C McCormack
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - P N Breysse
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - N N Hansel
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
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Kim SR, Kim HJ, Kim DI, Lee KB, Park HJ, Jeong JS, Cho SH, Lee YC. Blockade of Interplay between IL-17A and Endoplasmic Reticulum Stress Attenuates LPS-Induced Lung Injury. Am J Cancer Res 2015; 5:1343-62. [PMID: 26516372 PMCID: PMC4615737 DOI: 10.7150/thno.11685] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 08/30/2015] [Indexed: 12/22/2022] Open
Abstract
IL-17 is a cytokine mainly from IL-17-producing T cells, which are one of subsets of CD4+ T cells and play a role in adaptive immune system. Recent studies have demonstrated that IL-17A can act rapidly as an innate immune responder during infection before the onset of its classic adaptive immune response. This role of IL-17A in innate immune response is implicated in lipopolysaccharide (LPS)-induced lung inflammation. Very recently, we have reported that endoplasmic reticulum (ER) stress is involved in LPS-induced lung inflammation in vivo and in vitro. This study aimed to elucidate the role of IL-17A in LPS-induced lung injury, focusing on the link with ER stress. We treated a murine model of LPS-induced lung injury with IL-17A neutralizing antibody and 4-phenylbutyrate (4-PBA), a representative ER stress inhibitor. In addition, we evaluated the effects of IL-17A on ER stress in LPS-stimulated bronchial epithelial cells. Our results showed that inhibition of IL-17A decreased LPS-induced pulmonary neutrophilia, vascular leakage, nuclear translocation of nuclear factor-κB (NF-κB), infiltration of dendritic cells, increased expression of Toll-like receptor 4 (TLR4), activation of NLRP3 inflammasome, and increased ER stress in the lung. 4-PBA or TAK-242, a TLR4 inhibitor attenuated expression of IL-17A thereby improving LPS-induced lung inflammation. Intriguingly, we observed that stimulation with LPS increased expression of IL-17A in airway epithelial cells and co-stimulation with IL-17A further increased ER stress and NF-κB activation. This study indicates that the interrelationship between IL-17A and ER stress plays an important role in LPS-induced injury showing a positive feedback in airway epithelial cells and suggests that targeting their interaction can be a potential therapeutic approach to overcome one of severe refractory pulmonary disorders.
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Ivester KM, Couëtil LL, Zimmerman NJ. Investigating the link between particulate exposure and airway inflammation in the horse. J Vet Intern Med 2014; 28:1653-65. [PMID: 25273818 PMCID: PMC4895611 DOI: 10.1111/jvim.12458] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 07/25/2014] [Accepted: 08/20/2014] [Indexed: 01/30/2023] Open
Abstract
Inhalant exposure to airborne irritants commonly encountered in horse stables is implicated in the pathogenesis of inflammatory airway disease (IAD) and recurrent airway obstruction (RAO), non‐infectious, inflammatory pulmonary disorders that impact the health and performance of horses across all equine disciplines. IAD and RAO have overlapping clinical, cytological, and functional manifestations of the pulmonary response to organic dust and noxious gases encountered in the barn environment. Study of these diseases has provided important but incomplete understanding of the effect of air quality upon the respiratory health of horses. In this review, the principles of particulate exposure assessment, including health‐related aerosol size fractions and size‐selective sampling, the factors influencing air quality in equine environments, and the effect of air quality on the equine respiratory tract are discussed. The objective of this review is to provide the reader with a summary of the most common chronic inflammatory airway diseases in the horse and the principles of air sampling that are essential to the planning, interpretation, and assessment of equine respiratory health‐related exposure studies.
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Affiliation(s)
- K M Ivester
- Department of Veterinary Clinical Sciences, Purdue University College of Veterinary Medicine, West Lafayette, IN
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Wan GH, Yan DC, Tung TH, Tang CS, Liu CH. Seasonal Changes in Endotoxin Exposure and Its Relationship to Exhaled Nitric Oxide and Exhaled Breath Condensate pH Levels in Atopic and Healthy Children. PLoS One 2013; 8:e66785. [PMID: 23840530 PMCID: PMC3686731 DOI: 10.1371/journal.pone.0066785] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 05/13/2013] [Indexed: 11/20/2022] Open
Abstract
Endotoxin, a component of the cell walls of gram-negative bacteria, is a contaminant in organic dusts (house dust) and aerosols. In humans, small amounts of endotoxin may cause a local inflammatory response. Exhaled nitric oxide (eNO) levels, an inflammation indicator, are associated with the pH values of exhaled breath condensate (EBC). This study evaluated seasonal changes on indoor endotoxin concentrations in homes and the relationships between endotoxin exposure and eNO/EBC pH levels for healthy children and children with allergy-related respiratory diseases. In total, 34 children with allergy-related respiratory diseases and 24 healthy children were enrolled. Indoor air quality measurements and dust sample analysis for endotoxin were conducted once each season inside 58 surveyed homes. The eNO, EBC pH levels, and pulmonary function of the children were also determined. The highest endotoxin concentrations were on kitchen floors of homes of children with allergy-related respiratory diseases and healthy children, and on bedroom floors of homes of asthmatic children and healthy children. Seasonal changes existed in endotoxin concentrations in dust samples from homes of children with allergic rhinitis, with or without asthma, and in EBC pH values among healthy children and those with allergy-related respiratory diseases. Strong relationships existed between endotoxin exposure and EBC pH values in children with allergic rhinitis.
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Affiliation(s)
- Gwo-Hwa Wan
- Department of Respiratory Therapy, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
- * E-mail:
| | - Dah-Chin Yan
- Division of Taipei Pediatrics, Department of Pediatrics, Chang Gung Children’s Hospital, Chang Gung Memorial Hospital, Taipei, Taiwan
- Department of Medicine, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
- Department of Respiratory Therapy, Chang Gung Memorial Hospital, Taipei, Taiwan
| | - Tao-Hsin Tung
- Department of Medical Research and Education, Cheng-Hsin General Hospital, Taipei, Taiwan
| | - Chin-Sheng Tang
- Department of Public Health, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Chiu-Hsin Liu
- Department of Respiratory Therapy, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
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Janke T, Schwaiger K, Ege M, Fahn C, von Mutius E, Bauer J, Mayer M. Analysis of the Fungal Flora in Environmental Dust Samples by PCR–SSCP Method. Curr Microbiol 2013; 67:156-69. [DOI: 10.1007/s00284-013-0344-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 02/22/2013] [Indexed: 10/27/2022]
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Szponar B, Larsson L, Domagała-Kulawik J. Endotoxin markers in bronchoalveolar lavage fluid of patients with interstitial lung diseases. Multidiscip Respir Med 2012; 7:54. [PMID: 23259971 PMCID: PMC3551689 DOI: 10.1186/2049-6958-7-54] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 12/14/2012] [Indexed: 11/10/2022] Open
Abstract
UNLABELLED BACKGROUND Exposure to inhaled endotoxins (lipopolysaccharides, LPS) of Gram-negative bacteria commonly found in indoor environments and assessed in secondary tobacco smoke, has been associated with airway inflammation and asthma exacerbation. The bronchoalveolar lavage fluid (BALf) from patients with interstitial lung diseases (sarcoidosis, lung fibrosis, smoking-related ILD, eosinophilic disorders) was analyzed for the markers of lipopolysaccharide (LPS, endotoxin). METHODS BALf was obtained from patients with diffuse lung diseases: idiopathic pulmonary fibrosis (n = 42), sarcoidosis (n = 22), smoking-related-ILD (n = 11) and eosinophilic disorders (n = 8). Total cell count and differential cell count were performed. In addition, samples were analyzed for 3-hydroxy fatty acids (3-OHFAs) of 10-18 carbon chain lengths, as markers of LPS, by gas chromatography-tandem mass spectrometry. RESULTS The highest LPS concentration was found in patients with eosinophilic disorders and the lowest in patients with sarcoidosis (p< 0.05) followed by the lung fibrosis and the sr-ILD patients. The difference between LPS in BALf with extremely high eosinophil proportion (> 25%) and those with lower proportion was also significant (p = 0.014). A significant correlation was found between LPS and eosinophils, but not between LPS and lymphocytes, neutrophils, or macrophages count. CONCLUSIONS A positive relationship of LPS and eosinophilic pulmonary disorders may be linked to a persistent eosinophil activation mediated by Th2 pathway: chronic endotoxin exposure would intensify Th2 pathway resulting in fibrosis and, at the same time, eosinophil stimulation, and hence in eosinophilic pulmonary disorders.
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Affiliation(s)
- Bogumiła Szponar
- Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53-114, Wroclaw, Poland.
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Virtala R, Ekman AK, Jansson L, Westin U, Cardell LO. Airway inflammation evaluated in a human nasal lipopolysaccharide challenge model by investigating the effect of a CXCR2 inhibitor. Clin Exp Allergy 2011; 42:590-6. [DOI: 10.1111/j.1365-2222.2011.03921.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 10/07/2011] [Accepted: 10/13/2011] [Indexed: 12/18/2022]
Affiliation(s)
| | - A.-K. Ekman
- Division of ENT Diseases; CLINTEC; Karolinska Institutet; Karolinska University Hospital; Stockholm Sweden
| | | | - U. Westin
- Department of Otorhinolaryngology; Skåne University Hospital; Lund University; Malmö Sweden
| | - L. O. Cardell
- Division of ENT Diseases; CLINTEC; Karolinska Institutet; Karolinska University Hospital; Stockholm Sweden
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Abstract
Common lung diseases such as asthma, COPD, and pulmonary fibrosis cause significant morbidity and mortality in the U.S. and worldwide. Research investigating the mechanisms of disease etiology has clearly indicated that genetic attributes and environmental exposures each play important roles in the development of these diseases. Emerging evidence underscores the importance of the interplay between genetic predisposition and environmental factors in fully understanding the development of lung disease. Herein we discuss recent advances in knowledge and technology surrounding the role of genetics, the environment, and gene-environment interactions in these common lung diseases.
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Affiliation(s)
- Max A Seibold
- Center for Genes, Environment, and Health, National Jewish Health, Denver, Colorado 80206, USA.
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Just N, Kirychuk S, Gilbert Y, Létourneau V, Veillette M, Singh B, Duchaine C. Bacterial diversity characterization of bioaerosols from cage-housed and floor-housed poultry operations. ENVIRONMENTAL RESEARCH 2011; 111:492-498. [PMID: 21288509 DOI: 10.1016/j.envres.2011.01.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 01/06/2011] [Accepted: 01/10/2011] [Indexed: 05/30/2023]
Abstract
BACKGROUND Although bioaerosols from both cage-housed (CH) and floor-housed (FH) poultry operations are highly concentrated, workers from CH operations have reported a greater prevalence of respiratory symptoms. OBJECTIVE The objective of this study was to directly compare bacteria, both quantitatively and qualitatively, in bioaerosols from CH and FH poultry facilities. METHODS Bioaerosols were collected from fifteen CH and fifteen FH poultry operations, using stationary area samplers as well as personal sampling devices. Dust, endotoxin and bacteria were quantified and bacterial diversity was investigated using PCR followed by denaturing gradient gel electrophoresis (DGGE). RESULTS Dust (p<0.001), endotoxin (p<0.05) and bacteria (p<0.05) were significantly higher in personal bioaerosols of FH poultry operations than CH bioaerosols. Although dust and endotoxin did not differ significantly between area and personal samples within each barn type, clustering analysis of DGGE profiles of bacteria revealed that area and personal samples shared less than 10% similarity. These data suggest that area samples are not representative of personal bacteria exposures, which may be affected by worker movement, bacteria carried on the worker and worker location. Personal DGGE profiles from CH and FH operations shared less than 20% similarity and composite analysis showed that bacteria were more prevalent in personal samples from CH bioaerosols than FH bioaerosols. CONCLUSIONS Bacteria concentration and diversity are significantly different between bioaerosols from CH and FH poultry operations.
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Affiliation(s)
- Natasha Just
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan, Canada S7N 5B4
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Charavaryamath C, Lemieux H, Singh Suri S, Selvakumar P, Sharma RK, Singh B. Expression and activities of N-myristoyltransferase and calcineurin in normal and inflamed lungs. Exp Lung Res 2009; 35:729-47. [PMID: 19916857 DOI: 10.3109/01902140902870741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The role of N-myristoyltransferase and calcineurin is well established in signaling pathways. However, there are no data on their expression and activities in normal and inflamed lungs. The mechanisms of lung inflammation induced following administration of lipopolysaccharides (LPS) or exposure to swine barn air remain unclear. Therefore, we examined expression and activities of N-myristoyltransferase and calcineurin in normal and inflamed lungs of rats. Histopathology showed acute inflammation in the lungs of rats exposed to barn air or LPS but not of control rats. There was no difference in the activities of N-myristoyltransferase and calcineurin among the control, barn-exposed, and LPS-treated rat lungs. Although N-myristoyltransferase and calcineurin were localized in airway epithelium, blood vessel walls, alveolar macrophages, and septa in the lungs of rats from all the groups, the staining intensity was increased in the lungs from rats exposed to intravenous LPS or barn air. Densitometric analyses of Western blots of 55- and 60-kDa polypeptide bands corresponding to N-myristoyltransferase and calcineurin, respectively, in the lung homogenates revealed no differences among the groups. These results show that expression of myristoyltransferase and calcineurin in lung epithelium and endothelium and a cell-specific increase in immunohistochemical expression.
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Seth R, Romaschin AD, Ribeiro M, Tarlo SM. CR3 (CD11b/CD18) activation of nasal neutrophils: a measure of upper airway endotoxin exposure. Biomarkers 2009; 14:473-9. [DOI: 10.3109/13547500903183947] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Hofmann AM, Abraham SN. New roles for mast cells in modulating allergic reactions and immunity against pathogens. Curr Opin Immunol 2009; 21:679-86. [PMID: 19828301 DOI: 10.1016/j.coi.2009.09.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Accepted: 09/01/2009] [Indexed: 12/22/2022]
Abstract
Mast cells (MCs) have primarily been associated with mediating the pathological secondary responses to allergens in sensitized hosts. In view of the recent evidence for a MC role in modulating primary immune responses to pathogens, the likelihood for a role of MCs in influencing primary immune response to allergens has grown. New evidence suggests that MCs drive the development of Th2 responses to allergens, particularly when allergen exposure occurs concomitantly with exposure to pathogen products present in the environment. These new roles for MCs in allergy and infection suggest additional drug targets to prevent the development of allergic disease and allergic exacerbations of established disease.
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Affiliation(s)
- Alison M Hofmann
- Division of Pediatric Allergy and Immunology, Duke University, DUMC 2898, Durham, NC 27710, USA.
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Just N, Duchaine C, Singh B. An aerobiological perspective of dust in cage-housed and floor-housed poultry operations. J Occup Med Toxicol 2009; 4:13. [PMID: 19515256 PMCID: PMC2701955 DOI: 10.1186/1745-6673-4-13] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Accepted: 06/10/2009] [Indexed: 01/26/2023] Open
Abstract
The Canadian poultry production industry contributes nearly $10 billion to the Canadian economy and employs nearly 50,000 workers. However, modern poultry facilities are highly contaminated with airborne dust. Although there are many bioaerosols in the poultry barn environment, endotoxin is typically attributed with the negative respiratory symptoms observed in workers. These adverse respiratory symptoms have a higher prevalence in poultry workers compared to workers from other animal confinement buildings. Workers in cage-housed operations compared to floor-housed facilities report a higher prevalence of some respiratory symptoms. We review the current state of knowledge on airborne dust in poultry barns and respiratory dysfunction in poultry workers while highlighting the areas that need further investigation. Our review focuses on the aerobiological pathway of poultry dust including the source and aerosolization of dust and worker exposure and response. Further understanding of the source and aerosolization of dust in poultry operations will aid in the development of management practices to reduce worker exposure and response.
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Affiliation(s)
- Natasha Just
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada.
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Snyder JC, Reynolds SD, Hollingsworth JW, Li Z, Kaminski N, Stripp BR. Clara cells attenuate the inflammatory response through regulation of macrophage behavior. Am J Respir Cell Mol Biol 2009; 42:161-71. [PMID: 19423773 DOI: 10.1165/rcmb.2008-0353oc] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Chronic lung diseases are marked by excessive inflammation and epithelial remodeling. Reduced Clara cell secretory function and corresponding decreases in the abundance of the major Clara cell secretory protein (CCSP) are characteristically seen in these disease states. We sought to define the impact of Clara cell and CCSP depletion on regulation of the lung inflammatory response. We used chemical and genetic mouse models of Clara cell and CCSP deficiency (CCSP(-/-)) coupled with Pseudomonas aeruginosa LPS elicited inflammation. Exposure of Clara cell-depleted or CCSP(-/-) mice to LPS resulted in augmented inflammation as assessed by polymorphonuclear leukocyte recruitment to the airspace. Gene expression analysis and pathway modeling of the CCSP(-/-) inflammatory response implicated increased TNF-alpha signaling. Consistent with this model was the demonstration of significantly elevated TNF-alpha in airway fluid of LPS-stimulated CCSP(-/-) mice compared with similarly exposed wild-type mice. Increased LPS-elicited TNF-alpha production was also observed in cultured lung macrophages from CCSP(-/-) mice compared with wild-type mice. We demonstrate that macrophages from Clara cell-depleted and CCSP(-/-) mice displayed increased Toll-like receptor 4 surface expression. Our results provide evidence that Clara cells can attenuate inflammation through regulation of macrophage behavior, and suggest that epithelial remodeling leading to reduced Clara cell secretory function is an important factor that increases the intensity of lung inflammation in chronic lung disease.
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Affiliation(s)
- Joshua C Snyder
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Liebers V, Stubel H, Düser M, Brüning T, Raulf-Heimsoth M. Standardization of whole blood assay for determination of pyrogenic activity in organic dust samples. Int J Hyg Environ Health 2009; 212:547-56. [PMID: 19395310 DOI: 10.1016/j.ijheh.2009.03.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 03/11/2009] [Accepted: 03/14/2009] [Indexed: 10/20/2022]
Abstract
To characterize bioaerosol exposure at workplaces standardized methods are necessary. Activity of endotoxin, one component of organic dust, can be quantified with the Limulus-Amoebocyte Lysat test (LAL test). Further information with respect to pyrogenic activity of the organic dust can be achieved by measuring cytokine release of human blood after stimulation with the dust or its extract (whole blood assay). The aim of our study was the standardization of the whole blood assay (WBA) while using cryo-preserved human blood (Qualis Laboratorium) and to compare the outcome of the different cytokines determined by incubation of the blood cells with extracts from dust samples collected at various workplaces. Cytokine release (IL-1 beta, IL-6, IL-8, TNF-alpha, MCP-1) was measured by ELISA after stimulation of fresh blood from ten donors as well as cryo-preserved human blood. In both cases blood was stimulated with E. coli endotoxin as well as with 30 dust filter extracts from various workplaces. All dust filter extracts were investigated in the WBA using cryo-preserved blood as well as with LAL test. E. coli endotoxin stimulated the release of IL-1 beta, IL-6, IL-8, TNF-alpha and MCP-1 in a dose-dependent manner in fresh as well as cryo-preserved human whole blood. 200 pg/ml E. coli endotoxin induced maximal cytokine release in cryo-preserved blood (mean value for IL-1 beta 2509+/-418 pg/ml; n=13 experiments) whereas fresh blood of single donors reached a maximum release when stimulated with 50 ng/ml endotoxin (mean value of ten donors 1125+/-553 pg/ml IL-1beta). Using cryo-preserved blood the coefficient of variation (CV) regarding the interassay variability was below 21% for all cytokines measured. Regarding 26 dust sample extracts correlation coefficient r2 for LAL test and WBA was between 0.90 and 0.93 (Pearson) for IL-1 beta, IL-6, IL-8 and TNF-alpha whereas correlation for MCP-1 was lower (r(2)=0.59). Two dust sample extracts which showed similar reactivity patterns in LAL test as well as in WBA with respect to IL-1 beta, IL-6, IL-8 and TNF-alpha could be differentiated by measuring MCP-1. In conclusion, cryo-preserved blood pools are suitable to standardize WBA. Combination of different outcome variables like IL-1 beta and MCP-1 improve the characterization from the inflammatory potency of workplace related dust samples.
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Affiliation(s)
- Verena Liebers
- BGFA-Research Institute of Occupational Medicine of German Social Accident; Insurance, Ruhr-University Bochum, Germany.
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20
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Application of PCR-SSCP for molecular epidemiological studies on the exposure of farm children to bacteria in environmental dust. J Microbiol Methods 2008; 73:49-56. [PMID: 18321601 DOI: 10.1016/j.mimet.2008.01.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Revised: 01/21/2008] [Accepted: 01/25/2008] [Indexed: 11/20/2022]
Abstract
The environmental exposure of farm children to microorganisms in dust has become a focus of interest, since microbial exposure on farms has been related to a reduced prevalence of asthma and atopic diseases in children. Previous studies almost exclusively focused on the determination of microbial counts using conventional culturing or the determination of microbial compounds i.e. endotoxins. In this study PCR-SSCP (single-strand conformation polymorphism) was modified for characterising bacterial communities in environmental dusts and their sensitivity and reproducibility was validated. A fivefold repeated PCR-SSCP analyses of a well homogenised mattress dust, cow-shed dust, swine-shed dust, chicken-shed dust and a horse-shed dust sample, respectively, showed similarities, based on Pearson correlations, ranging from 89.7% to 95.2%. The reproducibility of day to day variations (five days) and gel to gel variations (five gels) was also around 90%. The detection limit of Escherichia coli was 7 x 10(1) cfu g(-1) whereas Listeria monocytogenes and Bacillus licheniformis containing 30% spores showed visible bands at 7 x1 0(2) cfu g(-1). Application of this method to dust samples of 37 sheds and 63 children's mattresses showed that distinct farm environment dusts reflected different SSCP profiles. However, digital analysis of the gels showed that some bands in the profiles of shed- and mattress dusts were found at the same position in the gels. By excision, cloning, sequencing and phylogenetic analyses, these bands were identified as Corynebacterium tuberculostearicum, Corynebacterium mucifaciens, Staphylococcus epidermidis, Acinetobacter lwoffii, Brevibacterium iodinum, Brevibacterium linens and Arthrobacter spp, respectively. These results may reflect transfer of microorganisms from animal sheds to mattresses. In conclusion this study demonstrates that PCR-SSCP is a promising method with sensitive detection limits and moderate sample variances to be applied for epidemiological studies characterizing the exposure of farmers using environmental dust.
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Liebers V, Raulf-Heimsoth M, Linsel G, Goldscheid N, Düser M, Stubel H, Brüning T. Evaluation of quantification methods of occupational endotoxin exposure. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2007; 70:1798-1805. [PMID: 17934952 DOI: 10.1080/15287390701459072] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Endotoxin has been identified as important component of organic-dust exposure and is suspected as main cause of work-related adverse health effects in dusty areas. Although the determination of endotoxin levels by using the Limulus amoebocyte lysate (LAL) assay is internationally accepted, reliability and variation of values measured with this test remain a point of discussion. Therefore, the purpose of the study was to determine the influence of different parameters on endotoxin activity measured in airborne samples. This study thus analyzed: (a) dust filter extraction procedures, (b) storage of samples, (c) usage of different commercially available LAL assays, and (d) results of the whole blood assay (WBA) compared to the LAL test. Using a parallel sampler, 120 filters were loaded with dust at 4 different occupational settings and extracted in 2 labs using a standardized protocol. Parameters like Tween in the extraction medium, extraction volume, centrifugation speed, and material of tubes used for extraction were tested. The LAL test and the WBA were able to determine the differences in dust load of filters obtained from the settings investigated. In addition, results varied significantly with modifications in extraction procedures. Using Tween for filter extraction mainly influenced the resulting endotoxin activity. In addition, LAL test differences according to manufacturer of LAL test, extraction volume, and whether the samples are freshly processed or frozen also resulted in significant variations in the endotoxin levels. In conclusion, a reliable assessment of exposure to endotoxin activity is only possible if standard operation procedures (SOPs) for sampling and determination are established.
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Affiliation(s)
- V Liebers
- Research Institute of Occupational Medicine (BGFA of German Social Accident Insurance), Ruhr-University Bochum, Bochum, Germany.
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22
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Hollingsworth JW, Whitehead GS, Lin KL, Nakano H, Gunn MD, Schwartz DA, Cook DN. TLR4 signaling attenuates ongoing allergic inflammation. THE JOURNAL OF IMMUNOLOGY 2006; 176:5856-62. [PMID: 16670292 DOI: 10.4049/jimmunol.176.10.5856] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The relationship between LPS exposure and allergic asthma is poorly understood. Epidemiologic studies in humans have found that exposure to LPS can protect, have no effect, or exacerbate allergic asthma. Similarly, LPS has had variable effects on allergic pulmonary inflammation in the mouse, depending on the model used. In the present study, we studied the effect of very low doses of LPS in models of both short-term and long-term allergen challenge. When challenged with allergen for short periods, wild-type and tlr4-deficient mice had similar responses. However, when challenged for periods of 1 wk or longer, tlr4-deficient mice developed dramatically increased airway eosinophils, serum IgE, and Th2 cytokines compared with similarly challenged, genetically matched C57BL/6 mice. The relative attenuation of allergic responses seen in C57BL/6 mice was dependent on bone marrow-derived cell-specific expression of tlr4, and was not associated with an increase in Th1 responses. The number of dendritic cells in lungs of challenged tlr4-deficient mice was significantly increased compared with those in challenged C57BL/6 mice. No differences were seen in the abilities of naive C57BL/6 and tlr4-deficient mice to develop allergen-specific tolerance after exposure to similar preparations of OVA, suggesting that tolerance and regulation of existing inflammation develop through different mechanisms. The attenuation of eosinophilic inflammation in C57BL/6 mice was abolished when these mice were challenged with OVA supplemented with additional LPS. Together, these findings show that low doses of endotoxin can have regulatory effects on allergic inflammation, particularly in the setting of ongoing allergen exposure.
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Affiliation(s)
- John W Hollingsworth
- Division of Pulmonary, Allergy, and Critical Care Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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Abstract
Asthma and atopy are complex phenotypes that are influenced by both genetic and environmental factors. A review of nearly 500 papers on disease association studies identified 25 genes that have been associated with an asthma or atopy phenotype in six or more populations. An additional 54 genes have been associated in 2-5 populations. Here, we discuss the methods that have been used to identify susceptibility genes for common diseases and overview the status of asthma genetic research. Finally, current challenges and future directions are discussed.
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Affiliation(s)
- C Ober
- Department of Human Genetics, The University of Chicago, Chicago, IL 60615, USA.
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Douwes J, van Strien R, Doekes G, Smit J, Kerkhof M, Gerritsen J, Postma D, de Jongste J, Travier N, Brunekreef B. Does early indoor microbial exposure reduce the risk of asthma? The Prevention and Incidence of Asthma and Mite Allergy birth cohort study. J Allergy Clin Immunol 2006; 117:1067-73. [PMID: 16675334 DOI: 10.1016/j.jaci.2006.02.002] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2005] [Revised: 01/29/2006] [Accepted: 02/01/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND Exposure to microbial agents might inhibit the development of atopy and asthma. OBJECTIVE We measured the association between microbial exposure assessed at 3 months and the development of atopic sensitization and doctor-diagnosed (DD) asthma and wheeze in the first 4 years in a birth cohort study of children with atopic mothers. METHODS Endotoxin, fungal (1-->3)-beta-D-glucans, extracellular polysaccharides from the genera Penicillium and Aspergillus (EPS-Pen/Asp), and dust on living room floors were measured at 3 months of age. Serum IgE levels against common allergens were determined at 1 and 4 years, and questionnaire information about respiratory morbidity was collected yearly. RESULTS Microbial levels in mattresses were low and not associated with serum IgE levels, DD asthma, and wheeze. Floor levels of biocontaminants and dust, on the other hand, were inversely associated with DD asthma, being most pronounced for endotoxin (odds ratio [OR], 0.40; 95% CI, 0.21-0.77) and EPS-Pen/Asp (OR, 0.42; 95% CI, 0.18-0.99). Mutual adjustment for other exposures did not significantly alter the results for endotoxin and only moderately affected the results for EPS-Pen/Asp. Persistent wheeze was also consistently less common in the high-exposure group, being significant only for EPS-Pen/Asp (OR, 0.37; 95% CI, 0.15-0.96). Transient wheeze and wheeze in the past 12 months were also reduced, but effects were smaller and not significant. Relationships with serum-specific IgE levels, which could only be assessed in 41% at age 4 years, were less pronounced and statistically significant only for EPS-Pen/Asp. CONCLUSIONS Early exposure to common microbial contaminants, including fungal agents, might protect against asthma. CLINICAL IMPLICATIONS Microbial exposure in early life might protect against asthma and might constitute a novel target for prevention.
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Affiliation(s)
- Jeroen Douwes
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, Amsterdam
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25
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Affiliation(s)
- K Radon
- Unit for Occupational and Environmental Epidemiology & Net Teaching, Institute and Outpatient Clinic for Occupational and Environmental Medicine, Munich, Germany.
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Erin EM, Neighbour H, Tan AJ, Min Kon O, Durham SR, Hansel TT. Nasal testing for novel anti-inflammatory agents. Clin Exp Allergy 2006; 35:981-5. [PMID: 16120078 DOI: 10.1111/j.1365-2222.2005.02311.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Ober C, Thompson EE. Rethinking genetic models of asthma: the role of environmental modifiers. Curr Opin Immunol 2005; 17:670-8. [PMID: 16214315 DOI: 10.1016/j.coi.2005.09.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2005] [Accepted: 09/21/2005] [Indexed: 01/23/2023]
Abstract
Asthma is a common, chronic disease with a complex etiology. To date, more than 35 genes have been associated with asthma or related phenotypes in multiple populations, but none of them has been shown to contribute to risk in all populations studied. We suggest that genetic susceptibility is both context dependent and developmentally regulated, and that ignoring the environmental context will miss many important associations and clues to pathogenesis. We define 'environment' broadly to include the in utero environment, maternal affection status and sex, and propose that epigenetic mechanisms are the link between our genes and our environment.
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Affiliation(s)
- Carole Ober
- Department of Human Genetics, 920 East 58(th) Street, The University of Chicago, Chicago, Illinois 60637, USA.
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28
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Chen W, KuoLee R, Patel GB. Therapeutic potential of microbes and microbial products in the management of human allergic asthma. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.15.7.789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wjst M. Another explanation for the low allergy rate in the rural Alpine foothills. Clin Mol Allergy 2005; 3:7. [PMID: 15935102 PMCID: PMC1177973 DOI: 10.1186/1476-7961-3-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2005] [Accepted: 06/05/2005] [Indexed: 11/29/2022] Open
Abstract
A low allergy rate in coal and wood heated homes has been described in the small villages in the Alpine foothills and subsequently found to be associated with the farming environment. This was interpreted within the framework of the hygiene hypothesis but there are also alternative explanations. Lower air pollution could be one reason, which is, however, unlikely since the differences between the Bavarian countryside and the Munich municipal area were only weak. There could be genetic differences between the urban and rural population by previous isolation or by self-selection. The potential drop-out of allergy genes, however, will also not explain the absent increase of allergies in two generations. More likely, other lifestyle factors are important. Dietary habits are different in farmers and a less frequent vitamin D supplementation of newborns (otherwise expected to be allergy promoting) has been shown recently. The underlying cause for the "non-allergic farm child" remains speculative until the transfer of any farm-associated factor is leading to a similar risk reduction in the general population.
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Affiliation(s)
- Matthias Wjst
- Institut für Epidemiologie GSF-Forschungszentrum für Umwelt und Gesundheit Ingolstädter, Landstrasse 1 D-85758, Neuherberg/Munich, Germany.
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