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Neun BW, Dobrovolskaia MA. Current Considerations and Practical Solutions for Overcoming Nanoparticle Interference with LAL Assays and Minimizing Endotoxin Contamination. Methods Mol Biol 2024; 2789:87-99. [PMID: 38506994 DOI: 10.1007/978-1-0716-3786-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
Monitoring endotoxin contamination in drugs and medical devices is required to avoid pyrogenic responses and septic shock in patients receiving these products. Endotoxin contamination of engineered nanomaterials and nanotechnology-based medical products represents a significant translational hurdle. Nanoparticles often interfere with an in vitro limulus amebocyte lysate (LAL) assay commonly used in the pharmaceutical industry for the detection and quantification of endotoxin. Such interference challenges the preclinical development of nanotechnology-formulated drugs and medical devices containing engineered nanomaterials. Protocols for the analysis of nanoparticles using LAL assays have been reported before. Here, we discuss considerations for selecting an LAL format and describe a few experimental approaches for overcoming nanoparticle interference with the LAL assays to obtain more accurate estimations of endotoxin contamination in nanotechnology-based products. The discussed approaches do not solve all types of nanoparticle interference with the LAL assays but could be used as a starting point to address the problem. This chapter also describes approaches to prevent endotoxin contamination in nanotechnology-formulated products.
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Affiliation(s)
- Barry W Neun
- Nanotechnology Characterization Laboratory, Cancer Research Technology Program, , Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Marina A Dobrovolskaia
- Nanotechnology Characterization Laboratory, Cancer Research Technology Program, , Frederick National Laboratory for Cancer Research, Frederick, MD, USA.
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2
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Madsen AM, Uhrbrand K, Kofoed VC, Fischer TK, Frederiksen MW. A cohort study of wastewater treatment plant workers: Association between levels of biomarkers of systemic inflammation and exposure to bacteria and fungi, and endotoxin as measured using two methods. WATER RESEARCH 2023; 231:119625. [PMID: 36680819 DOI: 10.1016/j.watres.2023.119625] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 12/05/2022] [Accepted: 01/15/2023] [Indexed: 06/17/2023]
Abstract
Work in wastewater treatment plants (WWTPs) can be associated with exposure to airborne microorganisms and endotoxin from the working environment. The aim of this study was to obtain knowledge about whether serum levels of the markers of systemic inflammation, C-reactive protein (CRP) and serum amyloid A (SAA), are associated with personal exposure to endotoxin, measured using the Limulus (endotoxinLimulus) and the rFC (endotoxinrFC) assays, as well as bacteria and fungi in a cohort of WWTP workers. Exposure and blood samples were collected for 11 workers over one year. Exposure to endotoxinLimulus-day and endotoxinrFC-day correlated significantly (r = 0.80, p<0.0001, n = 104), but endotoxinLimulus-day was 4.4 (Geometric mean (GM) value) times higher than endotoxinrFC-day (p<0.0001). The endotoxinLimulus-day, endotoxinrFC-day, bacteria, and fungal exposure as well as serum levels of CRP-day (GM=1.4 mg/l) and SAA-day (GM=12 mg/l) differed between workers. Serum levels of SAAday correlated significantly with CRPday (r = 0.30, p = 0.0068). The serum levels of CRPday were associated significantly with exposure to endotoxinLimulus-day. Exposure, SAA and CRP data were also analyzed as av. of each season, and SAAseason was associated positively and significantly with endotoxinLimulus-season and endotoxinrFC-season and negatively with fungalseason exposure. In conclusion, CRPday was associated with the endotoxinLimulus-day and SAAseason with endotoxinLimulus-season and endotoxinrFC-season exposure. Thus, we hereby document that WWTP workers are exposed to airborne endotoxin which seems to have a negative impact on their health.
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Affiliation(s)
- Anne Mette Madsen
- National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark.
| | - Katrine Uhrbrand
- National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark
| | - Victor Carp Kofoed
- National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark
| | - Thea K Fischer
- Dept of Clinical Research, Nordsjaellands Hospital, Denmark; Dept of Virus & Microbiological Special Diagnostics, Statens Serum Institut, Denmark
| | - Margit W Frederiksen
- National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark
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3
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Moriyama A, Ogura I, Fujita K. Potential issues specific to cytotoxicity tests of cellulose nanofibrils. J Appl Toxicol 2023; 43:195-207. [PMID: 36065078 PMCID: PMC10087788 DOI: 10.1002/jat.4390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/05/2022] [Accepted: 09/01/2022] [Indexed: 11/10/2022]
Abstract
Cellulose nanofibrils (also called cellulose nanofibers or nanofibrillated cellulose [CNFs]) are novel polymers derived from biomass with excellent physicochemical properties and various potential applications. However, the introduction of such new materials into the market requires thorough safety studies to be conducted. Recently, toxicity testing using cultured cells has attracted attention as a safety assessment that does not rely on experimental animals. This article reviews recent information regarding the cytotoxicity testing of CNFs and highlights the issues relevant to evaluating tests. In the literature, we found that a variety of cell lines and CNF exposure concentrations was evaluated. Furthermore, the results of cytotoxicity results tests differed and were not necessarily consistent. Numerous reports that we examined had not evaluated endotoxin/microbial contamination or the interaction of CNFs with the culture medium used in the tests. The following potential specific issues involved in CNF in vitro testing, were discussed: (1) endotoxin contamination, (2) microbial contamination, (3) adsorption of culture medium components to CNFs, and (4) changes in aggregation/agglomeration and dispersion states of CNFs resulting from culture medium components. In this review, the available measurement methods and solutions for these issues are also discussed. Addressing these points will lead to a better understanding of the cellular effects of CNFs and the development of safer CNFs.
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Affiliation(s)
- Akihiro Moriyama
- Research Institute of Science and Sustainability (RISS), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Isamu Ogura
- Research Institute of Science and Sustainability (RISS), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Katsuhide Fujita
- Research Institute of Science and Sustainability (RISS), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
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4
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Madsen AM, White JK, Nielsen JL, Keskin ME, Tendal K, Frederiksen MW. A cross sectional study on airborne inhalable microorganisms, endotoxin, and particles in pigeon coops - Risk assessment of exposure. ENVIRONMENTAL RESEARCH 2022; 204:112404. [PMID: 34838572 DOI: 10.1016/j.envres.2021.112404] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 11/13/2021] [Accepted: 11/15/2021] [Indexed: 06/13/2023]
Abstract
Pigeon breeding is associated with symptoms of the airways. The aim of this study is to illuminate the bacteriological and toxicological characteristics of airborne dust in pigeon coops. Airborne dust was sampled in 31 urban pigeon coops with homing and fancy pigeons, and following the dust was characterized. In total 141 different bacterial species were identified using MALDI-TOF MS, and of these 11 species are classified in risk group 2. Of the cultivable bacteria, Staphylococcus equorum was present in the highest concentration. Microorganisms in the dust were able to form biofilm, and the amount correlated positively with the number of bacteria. Next generation sequencing showed 180 genera with Acinetobacter in highest reads. On average 999 ± 225 ZOTUs were observed per sample with a Shannon-Wiener biodiversity index of 6.17 ± 0.24. Of the identified species the following have previously been suggested as causative agents of extrinsic allergic alveolitis: Alcaligenes faecalis, Bacillus subtilis, Pantoea agglomerans, Sphingobacterium spiritivorum, Thermoactinomyces sp., and Streptomyces albus. Staphylococcus was present on particles with sizes between 1.1 and > 7.0 μm with a geometric mean diameter of particles on 4.7 ± 1.1 μm. Concentrations of airborne endotoxin and dust were elevated compared to references, and the geometric mean concentrations were 102 EU/m3 and 1.07 mg dust/m3, respectively. Upon exposure to the airborne dust human granulocytes produced Reactive Oxidative Species during the first 5 min, and then no further reaction was observed. The concentrations of bacteria in general, Staphylococcus spp., and endotoxin and biodiversity were associated significantly with season, temperature and/or relative humidity, but not with type or density of pigeons. The bacterial composition and biodiversity indices were not affected by type of pigeon. In conclusion, the exposure to bacteria and endotoxin in pigeon houses should not be neglected in the evaluation of causative agents of airways symptoms among pigeon breeders.
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Affiliation(s)
- Anne Mette Madsen
- The National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark.
| | - John Kerr White
- The National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark; Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg Ø, Denmark; Department of Microbiology, Tumor and Cell Biology, Division of Clinical Microbiology, Karolinska Institute and Karolinska University Hospital, 17176, Stockholm, Sweden
| | - Jeppe Lund Nielsen
- Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg Ø, Denmark
| | - Mehmet Emin Keskin
- The National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark
| | - Kira Tendal
- The National Research Centre for the Working Environment, Lersø Parkallé 105, DK-2100, Copenhagen, Denmark
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Himly M, Geppert M, Hofer S, Hofstätter N, Horejs-Höck J, Duschl A. When Would Immunologists Consider a Nanomaterial to be Safe? Recommendations for Planning Studies on Nanosafety. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1907483. [PMID: 32239645 DOI: 10.1002/smll.201907483] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/06/2020] [Accepted: 02/10/2020] [Indexed: 06/11/2023]
Abstract
The immune system is professional in recognizing and responding to non-self, including nanomaterials. Immune responses by professional and nonprofessional immune cells are thus nearly inevitable upon exposure of cells and organisms to such materials. The state of research into taking the immune system into account in nanosafety studies is reviewed and three aspects in which further improvements are desirable are identified: 1) Due to technical limitations, more stringent testing for endotoxin contamination should be made. 2) Since under overdose conditions immunity shows unphysiological responses, all doses used should be justified by being equivalent to tissue-delivered doses. 3) When markers of acute inflammation or cell stress are observed, functional assays are necessary to distinguish between homeostatic fluctuation and genuine defensive or tolerogenic responses. Since immune activation can also indicate that the immune system considers a stimulus to be harmless and induces tolerance, activation markers by themselves do not necessarily imply a danger to the body. Guidelines such as these are necessary to approach the point where specific nanomaterials are classified as safe based on reliable testing strategies.
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Affiliation(s)
- Martin Himly
- Department for Biosciences & Allergy Cancer BioNano Research Centre, University of Salzburg, Hellbrunner Strasse 34, Salzburg, 5020, Austria
| | - Mark Geppert
- Department for Biosciences & Allergy Cancer BioNano Research Centre, University of Salzburg, Hellbrunner Strasse 34, Salzburg, 5020, Austria
| | - Sabine Hofer
- Department for Biosciences & Allergy Cancer BioNano Research Centre, University of Salzburg, Hellbrunner Strasse 34, Salzburg, 5020, Austria
| | - Norbert Hofstätter
- Department for Biosciences & Allergy Cancer BioNano Research Centre, University of Salzburg, Hellbrunner Strasse 34, Salzburg, 5020, Austria
| | - Jutta Horejs-Höck
- Department for Biosciences & Allergy Cancer BioNano Research Centre, University of Salzburg, Hellbrunner Strasse 34, Salzburg, 5020, Austria
| | - Albert Duschl
- Department for Biosciences & Allergy Cancer BioNano Research Centre, University of Salzburg, Hellbrunner Strasse 34, Salzburg, 5020, Austria
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Zhang C, Tian F, Zhang M, Zhang Z, Bai M, Guo G, Zheng W, Wang Q, Shi Y, Wang L. Endotoxin contamination, a potentially important inflammation factor in water and wastewater: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 681:365-378. [PMID: 31108357 DOI: 10.1016/j.scitotenv.2019.05.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/28/2019] [Accepted: 05/03/2019] [Indexed: 06/09/2023]
Abstract
Endotoxins, also referred to as lipopolysaccharides or pyrogens, are major components embedded in the outer cell wall membrane of most Gram-negative bacteria and some cyanobacteria. As common pyrogens and strong immune stimulators, health hazards associated with endotoxins in water and wastewater have been attracting attention in recent years. In this paper, the characteristics, existing forms, and detection assays of endotoxins in water and wastewater are reviewed. Cellular response and pathophysiological effects, and main exposure tracts of endotoxins in water and wastewater are discussed. Levels of endotoxin contamination in water, wastewater, and their aerosols are presented. The removal effects of different water and wastewater treatment processes are summarized. Hence, it is important to: (i) Improve investigations into endotoxin contamination in water and wastewater in order to identify their source, occurrence, and fate. (ii) Implement water and wastewater treatment processes capable of ensuring low levels of endotoxins. This review aims to identify efficient water and wastewater treatment processes capable of ensuring the production of WTPs and WWTPs effluents with a low level of endotoxin activity, and to guarantee the reduction of endotoxin exposure risks to the consumers of water and wastewater.
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Affiliation(s)
- Can Zhang
- Center for Disease Control and Prevention of Chinese PLA, Beijing 100071, China.
| | - Fang Tian
- School of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, China
| | - Minglu Zhang
- Department of Environmental Science and Engineering, Beijing Technology and Business University, Beijing 100048, China
| | - Zhiqing Zhang
- Tianjin Institute of Environmental and Operational Medicine, Tianjin 300050, China
| | - Miao Bai
- Center for Disease Control and Prevention of Chinese PLA, Beijing 100071, China
| | - Guang Guo
- School of Environmental Engineering, Nanjing Institute of Technology, Nanjing 211167, China
| | - Wenjie Zheng
- Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, Tianjin, 300387, China
| | - Qiang Wang
- Center for Disease Control and Prevention of Chinese PLA, Beijing 100071, China
| | - Yun Shi
- Center for Disease Control and Prevention of Chinese PLA, Beijing 100071, China
| | - Lili Wang
- Center for Disease Control and Prevention of Chinese PLA, Beijing 100071, China
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7
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Mbareche H, Morawska L, Duchaine C. On the interpretation of bioaerosol exposure measurements and impacts on health. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2019; 69:789-804. [PMID: 30821643 DOI: 10.1080/10962247.2019.1587552] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Bioaerosols are recognized as one of the main transmission routes for infectious diseases and are responsible for other various types of health effects through inhalation and potential ingestion. Associating exposure with bioaerosol and health problems is challenging, and adequate exposure monitoring is a top priority for aerosol scientists. The multiple factors affecting bioaerosol content, the variability in the focus of each bioaerosol exposure study, and the variations in experimental design and the standardization of methods make bioaerosol exposure studies very difficult. Therefore, the health impacts of bioaerosol exposure are still poorly understood. This paper presents a brief description of a state-of-the-art development in bioaerosol exposure studies supported by studies on several related subjects. The main objective of this paper is to propose new considerations for bioaerosol exposure guidelines and the development of tools and study designs to better interpret bioaerosol data. The principal observations and findings are the discrepancy of the applicable methods in bioaerosol studies that makes result comparison impossible. Furthermore, the silo mentality helps in creating a bigger gap in the knowledge accumulated about bioaerosol exposure. Innovative and original ideas are presented for aerosol scientists and health scientists to consider and discuss. Although many examples cited herein are from occupational exposure, the discussion has relevance to any human environment. This work gives concrete suggestions for how to design a full bioaerosol study that includes all of the key elements necessary to help understand the real impacts of bioaerosol exposure in the short term. The creation of the proposed bioaerosol public database could give crucial information to control the public health. Implications: How can we move toward a bioaerosol exposure guidelines? The creation of the bioaerosol public database will help accumulate information for long-term association studies and help determine specific exposure biomarkers to bioaerosols. The implementation of such work will lead to a deeper understanding and more efficient utilization of bioaerosol studies to prevent public health hazards.
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Affiliation(s)
- Hamza Mbareche
- a Centre de recherche de l'institut universitaire de cardiologie et de pneumologie de Québec , Quebec City , Quebec , Canada
- b Département de biochimie, de microbiologie et de bio-informatique , Faculté des sciences et de génie, Université Laval , Quebec City , Quebec , Canada
| | - Lidia Morawska
- c School of Chemistry, Physics, and Mechanical Engineering, Department of Environmental Technologies , Queensland University of Technology , Brisbane , Queensland , Australia
| | - Caroline Duchaine
- a Centre de recherche de l'institut universitaire de cardiologie et de pneumologie de Québec , Quebec City , Quebec , Canada
- b Département de biochimie, de microbiologie et de bio-informatique , Faculté des sciences et de génie, Université Laval , Quebec City , Quebec , Canada
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8
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Abstract
As a consequence of their increase in annual production and widespread distribution in the environment, nanoparticles potentially pose a significant public health risk. The sought-after catalytic activity granted by their physiochemical properties doubles as a hazard to physiological processes following exposure through inhalation, oral, transdermal, subcutaneous, and intravenous uptake. Upon uptake into the body, their size, morphology, surface charge, coating, and chemical composition augment the response of biological systems to the materials and enhance their toxicity. Identification of each property is necessary to predict the harm imposed by foreign nanomaterials in the body. Assay methods ranging from endotoxin and lactate dehydrogenase (LDH) signaling to apoptosis and oxidative stress detection supply valuable techniques for exposing biomarkers of nanoparticle-induced cellular damage. Spectroscopic investigation of epithelial barrier permeation and distribution within living cells reveals the proclivity of nanoparticles to penetrate the body's natural defensive boundaries and deposit themselves in cytotoxic locations. Combination of the various characterization methodologies and assays is required for every new nanoparticulate system despite preexisting data for similar systems due to the lack of deterministic trends among investigated nanoparticles. The propensity of nanomaterials to denature proteins and oxidize substrates in their local environment generates significant concern for the applicability of several traditional in vitro assays, and the modification of susceptible approaches into novel methods suitable for the evaluation of nanoparticles comprises the focus of future work centered on nanoparticle toxicity analysis.
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Affiliation(s)
- Dustin T Savage
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY, USA
| | - J Zach Hilt
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY, USA
| | - Thomas D Dziubla
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY, USA.
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Oteros J, Bartusel E, Alessandrini F, Núñez A, Moreno DA, Behrendt H, Schmidt-Weber C, Traidl-Hoffmann C, Buters J. Artemisia pollen is the main vector for airborne endotoxin. J Allergy Clin Immunol 2018; 143:369-377.e5. [PMID: 30012513 DOI: 10.1016/j.jaci.2018.05.040] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 04/05/2018] [Accepted: 05/14/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Endotoxin (LPS) released from gram-negative bacteria causes strong immunologic and inflammatory effects and, when airborne, can contribute to respiratory conditions, such as allergic asthma. OBJECTIVES We sought to identify the source of airborne endotoxin and the effect of this endotoxin on allergic sensitization. METHODS We determined LPS levels in outdoor air on a daily basis for 4 consecutive years in Munich (Germany) and Davos (Switzerland). Air was sampled as particulate matter (PM) greater than 10 μm (PM > 10) and PM between 2.5 and 10 μm. LPS levels were determined by using the recombinant Factor C assay. RESULTS More than 60% of the annual endotoxin exposure was detected in the PM > 10 fraction, showing that bacteria do not aerosolize as independent units or aggregates but adhered to large particles. In Munich 70% of annual exposure was detected between June 12th and August 28th. Multivariate modeling showed that endotoxin levels could be explained by phenological parameters (ie, plant growth). Indeed, days with high airborne endotoxin levels correlated well with the amount of Artemisia pollen in the air. Pollen collected from plants across Europe (100 locations) showed that the highest levels of endotoxin were detected on Artemisia vulgaris (mugwort) pollen, with little on other pollen. Microbiome analysis showed that LPS concentrations on mugwort pollen were related to the presence of Pseudomonas species and Pantoea species communities. In a mouse model of allergic disease, the presence of LPS on mugwort pollen was needed for allergic sensitization. CONCLUSIONS The majority of airborne endotoxin stems from bacteria dispersed with pollen of only one plant: mugwort. This LPS was essential for inducing inflammation of the lung and allergic sensitization.
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Affiliation(s)
- Jose Oteros
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technical University and Helmholtz Center Munich, Munich, Germany
| | - Elke Bartusel
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technical University and Helmholtz Center Munich, Munich, Germany; Christine Kühne-Center for Allergy Research and Education (CK-CARE), Davos, Switzerland
| | - Francesca Alessandrini
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technical University and Helmholtz Center Munich, Munich, Germany
| | - Andrés Núñez
- Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid (ETSII-UPM), Madrid, Spain
| | - Diego A Moreno
- Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid (ETSII-UPM), Madrid, Spain
| | - Heidrun Behrendt
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technical University and Helmholtz Center Munich, Munich, Germany; Christine Kühne-Center for Allergy Research and Education (CK-CARE), Davos, Switzerland
| | - Carsten Schmidt-Weber
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technical University and Helmholtz Center Munich, Munich, Germany
| | - Claudia Traidl-Hoffmann
- Christine Kühne-Center for Allergy Research and Education (CK-CARE), Davos, Switzerland; Institute of Environmental Medicine (UNIKA-T), Technische Universität München, Munich, Germany
| | - Jeroen Buters
- Center of Allergy & Environment (ZAUM), Member of the German Center for Lung Research (DZL), Technical University and Helmholtz Center Munich, Munich, Germany; Christine Kühne-Center for Allergy Research and Education (CK-CARE), Davos, Switzerland.
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Sun J, Zhu P, Wang X, Ji J, Habimana JDD, Shao J, Lei H, Zhang Y, Sun X. Cell Based-Green Fluorescent Biosensor Using Cytotoxic Pathway for Bacterial Lipopolysaccharide Recognition. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:6869-6876. [PMID: 29906103 DOI: 10.1021/acs.jafc.8b01542] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Lipopolysaccharide (LPS), a characteristic component of the outer membrane of Gram-negative bacteria, can be used as an effective biomarker to detect bacterial contamination. Here, we reported a 293/hTLR4A-MD2-CD14 cell-based fluorescent biosensor to detect and identify LPS, which is carried out in a 96-well microplate which is nondestructive, user-friendly, and highly efficient. The promoter sequence of the critical signaling pathway gene ZC3H12A (encoding MCPIP1 protein) and enhanced green fluorescence protein (EGFP) were combined to construct a recombinant plasmid, which was transferred into 293/hTLR4A-MD2-CD14 cells through lipid-mediated, DNA-transfection way. LPS was able to bind to TLR4 and coreceptors-induced signaling pathway could result in green fluorescent protein expression. Results show that stable transfected 293/hTLR4A-MD2-CD14 cells with LPS treatment could be directly and continually observed under a high content screening imaging system. The novel cell-based biosensor detects LPS at low concentration, along with the detection limit of 0.075 μg/mL. The cell-based biosensor was evaluated by differentiating Gram-negative and Gram-positive bacteria and detecting LPS in fruit juices as well. This proposed fluorescent biosensor has potential in sensing LPS optically in foodstuff and biological products, as well as bacteria identification, contributing to the control of foodborne diseases and ensurance of public food safety with its high throughput detection way.
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Affiliation(s)
- Jiadi Sun
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, Synergetic Innovation Center of Food Safety and Quality Control , Jiangnan University , Wuxi , Jiangsu 214122 , P. R. China
| | - Pei Zhu
- State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology , Dairy Research Institute, Bright Dairy & Food Co., Ltd. , Shanghai 200436 , China
| | - Xiumei Wang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, Synergetic Innovation Center of Food Safety and Quality Control , Jiangnan University , Wuxi , Jiangsu 214122 , P. R. China
| | - Jian Ji
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, Synergetic Innovation Center of Food Safety and Quality Control , Jiangnan University , Wuxi , Jiangsu 214122 , P. R. China
| | - Jean de Dieu Habimana
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, Synergetic Innovation Center of Food Safety and Quality Control , Jiangnan University , Wuxi , Jiangsu 214122 , P. R. China
| | - Jingdong Shao
- Zhangjiagang Entry-Exit Inspection and Quarantine Bureau , Zhangjiagang , Jiangsu 215600 , China
| | - Hongtao Lei
- Guangdong Provincial Key Laboratory of Food Quality and Safety , South China Agricultural University , Guangzhou 510642 , Guangdong Province P. R. China
| | - Yinzhi Zhang
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, Synergetic Innovation Center of Food Safety and Quality Control , Jiangnan University , Wuxi , Jiangsu 214122 , P. R. China
| | - Xiulan Sun
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, National Engineering Research Center for Functional Food, Synergetic Innovation Center of Food Safety and Quality Control , Jiangnan University , Wuxi , Jiangsu 214122 , P. R. China
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Chandra S, Wingender G, Greenbaum JA, Khurana A, Gholami AM, Ganesan AP, Rosenbach M, Jaffee K, Gern JE, Wood R, O'Connor G, Sandel M, Kattan M, Bacharier L, Togias A, Horner AA, Kronenberg M. Development of Asthma in Inner-City Children: Possible Roles of MAIT Cells and Variation in the Home Environment. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 200:1995-2003. [PMID: 29431692 PMCID: PMC5840005 DOI: 10.4049/jimmunol.1701525] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 01/10/2018] [Indexed: 12/11/2022]
Abstract
Humans have populations of innate-like T lymphocytes with an invariant TCR α-chain that recognize nonpeptide Ags, including invariant NKT (iNKT) cells and mucosal-associated invariant T (MAIT) cells. iNKT cell involvement in human asthma is controversial, whereas there has been little analysis of MAIT cells. Using peripheral blood cells from 110 participants from the Urban Environment and Childhood Asthma (URECA) birth cohort study, these cells were analyzed for number and function. We determined whether iNKT cell or MAIT cell frequency at 1 y is correlated with the cytokine polarization of mainstream CD4+ T cells and/or the development of asthma by age 7 y. Dust samples from 300 houses were tested for iNKT cell antigenic activity. Our results show that a higher MAIT cell frequency at 1 y of age was associated with a decreased risk of asthma by age 7 y. The frequency of MAIT cells was associated with increased production of IFN-γ by activated CD4+ T cells from the URECA cohort. iNKT cell antigenic activity in bedroom dust samples was associated with higher endotoxin concentration and also with reduced risk of asthma. In conclusion, MAIT cell frequency at 1 y may reflect the tendency of the immune system toward Th1 responses and is associated with protection from asthma. Additionally, iNKT cell antigenic activity may be a marker of houses with increased microbial exposures and therefore also with protection from asthma.
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Affiliation(s)
- Shilpi Chandra
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Gerhard Wingender
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
- Izmir International Biomedicine and Genome Institute, Balcova, 35340 Izmir, Turkey
| | - Jason A Greenbaum
- Bioinformatics Core Facility, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Archana Khurana
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Amin M Gholami
- Bioinformatics Core Facility, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Anusha-Preethi Ganesan
- Division of Pediatric Hematology-Oncology, Rady Children's Hospital, University of California San Diego, San Diego, CA 92093
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037
| | - Michael Rosenbach
- Department of Pediatrics, University of California San Diego, La Jolla, CA 92093
| | - Katy Jaffee
- Division of Federal Systems, Rho Inc., Chapel Hill, NC 27517
| | - James E Gern
- Department of Pediatrics and Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI 53726
| | - Robert Wood
- Division of Allergy and Immunology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 212876
| | - George O'Connor
- Department of Medicine, Boston University School of Medicine, Boston, MA 02118
| | - Megan Sandel
- Department of Medicine, Boston University School of Medicine, Boston, MA 02118
| | - Meyer Kattan
- Division of Pediatric Pulmonology, Department of Pediatrics, New York Presbyterian/Columbia University Medical Center, New York, NY 10032
| | - Leonard Bacharier
- Division of Allergy, Immunology, and Pulmonary Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Alkis Togias
- National Institutes of Health, National Institute of Allergy and Infectious Diseases, Rockville, MD 20852; and
| | - Anthony A Horner
- Department of Pediatrics, University of California San Diego, La Jolla, CA 92093
| | - Mitchell Kronenberg
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037;
- Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093
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12
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Pyrgiotakis G, Luu W, Zhang Z, Vaze N, DeLoid G, Rubio L, Graham WAC, Bell DC, Bousfield D, Demokritou P. Development of high throughput, high precision synthesis platforms and characterization methodologies for toxicological studies of nanocellulose. CELLULOSE (LONDON, ENGLAND) 2018. [PMID: 31839698 DOI: 10.1007/s10570-018-1718-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Cellulose is one of the most abundant natural polymers, is readily available, biodegradable, and inexpensive. Recently, interest is growing around nanoscale cellulose due to the sustainability of these materials, the novel properties, and the overall low environmental impact. The rapid expansion of nanocellulose uses in various applications makes the study of the toxicological properties of these materials of great importance to public health regulators. However, most of the current toxicological studies are highly conflicting, inconclusive, and contradictory. The major reasons for these discrepancies are the lack of standardized methods to produce industry-relevant reference nanocellulose and relevant characterization that will expand beyond the traditional cellulose characterization for applications. In order to address these issues, industry-relevant synthesis platforms were developed to produce nanocellulose of controlled properties that can be used as reference materials in toxicological studies. Herein, two types of nanocellulose were synthesized, cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) using the friction grinding platform and an acid hydrolysis approach respectively. The nanocellulose structures were characterized extensively regarding their physicochemical properties, including testing for endotoxins and bacteria contamination.
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Affiliation(s)
- Georgios Pyrgiotakis
- Center for Nanotechnology and Nanotoxicology, Harvard T. H. Chan School of Public Health, Boston, MA, 07016, USA
| | - Wing Luu
- Department of Chemical and Biological Engineering, University of Maine, Orono ME 04469 USA
| | - Zhenyuan Zhang
- Center for Nanotechnology and Nanotoxicology, Harvard T. H. Chan School of Public Health, Boston, MA, 07016, USA
| | - Nachiket Vaze
- Center for Nanotechnology and Nanotoxicology, Harvard T. H. Chan School of Public Health, Boston, MA, 07016, USA
| | - Glen DeLoid
- Center for Nanotechnology and Nanotoxicology, Harvard T. H. Chan School of Public Health, Boston, MA, 07016, USA
| | - Laura Rubio
- Center for Nanotechnology and Nanotoxicology, Harvard T. H. Chan School of Public Health, Boston, MA, 07016, USA
| | - W Adam C Graham
- Center for Nanoscale Systems, Harvard University, Cambridge MA 02138
| | - David C Bell
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138
- Center for Nanoscale Systems, Harvard University, Cambridge MA 02138
| | - Douglas Bousfield
- Department of Chemical and Biological Engineering, University of Maine, Orono ME 04469 USA
| | - Philip Demokritou
- Center for Nanotechnology and Nanotoxicology, Harvard T. H. Chan School of Public Health, Boston, MA, 07016, USA
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13
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Neun BW, Dobrovolskaia MA. Considerations and Some Practical Solutions to Overcome Nanoparticle Interference with LAL Assays and to Avoid Endotoxin Contamination in Nanoformulations. Methods Mol Biol 2018; 1682:23-33. [PMID: 29039090 DOI: 10.1007/978-1-4939-7352-1_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Monitoring endotoxin contamination in drugs and medical devices is required to avoid pyrogenic response and septic shock in patients receiving these products. Endotoxin contamination of engineered nanomaterials and nanotechnology-based medical products represents a significant translational hurdle. Nanoparticles often interfere with an in vitro Limulus Amebocyte Lysate (LAL) assay commonly used in the pharmaceutical industry for the detection and quantification of endotoxin. Such interference challenges the preclinical development of nanotechnology-formulated drugs and medical devices containing engineered nanomaterials. Protocols for analysis of nanoparticles using LAL assays have been reported before. Here, we discuss considerations for selecting an LAL format and describe a few experimental approaches for overcoming nanoparticle interference with the LAL assays to obtain more accurate estimation of endotoxin contamination in nanotechnology-based products. The discussed approaches do not solve all types of nanoparticle interference with the LAL assays but could be used as a starting point to address the problem. This chapter also describes approaches to prevent endotoxin contamination in nanotechnology-formulated products.
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Affiliation(s)
- Barry W Neun
- Cancer Research Technology Program¸ Nanotechnology Characterization Laboratory, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD, 21702, USA
| | - Marina A Dobrovolskaia
- Cancer Research Technology Program¸ Nanotechnology Characterization Laboratory, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD, 21702, USA.
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14
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Gold DR, Adamkiewicz G, Arshad SH, Celedón JC, Chapman MD, Chew GL, Cook DN, Custovic A, Gehring U, Gern JE, Johnson CC, Kennedy S, Koutrakis P, Leaderer B, Mitchell H, Litonjua AA, Mueller GA, O'Connor GT, Ownby D, Phipatanakul W, Persky V, Perzanowski MS, Ramsey CD, Salo PM, Schwaninger JM, Sordillo JE, Spira A, Suglia SF, Togias A, Zeldin DC, Matsui EC. NIAID, NIEHS, NHLBI, and MCAN Workshop Report: The indoor environment and childhood asthma-implications for home environmental intervention in asthma prevention and management. J Allergy Clin Immunol 2017; 140:933-949. [PMID: 28502823 PMCID: PMC5632590 DOI: 10.1016/j.jaci.2017.04.024] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 04/14/2017] [Indexed: 01/19/2023]
Abstract
Environmental exposures have been recognized as critical in the initiation and exacerbation of asthma, one of the most common chronic childhood diseases. The National Institute of Allergy and Infectious Diseases; National Institute of Environmental Health Sciences; National Heart, Lung, and Blood Institute; and Merck Childhood Asthma Network sponsored a joint workshop to discuss the current state of science with respect to the indoor environment and its effects on the development and morbidity of childhood asthma. The workshop included US and international experts with backgrounds in allergy/allergens, immunology, asthma, environmental health, environmental exposures and pollutants, epidemiology, public health, and bioinformatics. Workshop participants provided new insights into the biologic properties of indoor exposures, indoor exposure assessment, and exposure reduction techniques. This informed a primary focus of the workshop: to critically review trials and research relevant to the prevention or control of asthma through environmental intervention. The participants identified important limitations and gaps in scientific methodologies and knowledge and proposed and prioritized areas for future research. The group reviewed socioeconomic and structural challenges to changing environmental exposure and offered recommendations for creative study design to overcome these challenges in trials to improve asthma management. The recommendations of this workshop can serve as guidance for future research in the study of the indoor environment and on environmental interventions as they pertain to the prevention and management of asthma and airway allergies.
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Affiliation(s)
- Diane R Gold
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, Mass; Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Mass.
| | - Gary Adamkiewicz
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Mass
| | - Syed Hasan Arshad
- David Hide Asthma and Allergy Research Centre, Isle of Wight, and Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Juan C Celedón
- Division of Pulmonary Medicine, Allergy and Immunology, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, Pa
| | | | - Ginger L Chew
- Centers for Disease Control and Prevention (CDC), National Center for Environmental Health, Division of Environmental Hazards and Health Effects | Air Pollution and Respiratory Health Branch, Atlanta, Ga
| | - Donald N Cook
- Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC
| | - Adnan Custovic
- Section of Paediatrics and MRC and Asthma UK Centre in Allergic Mechanisms of Asthma, Imperial College London, London, United Kingdom
| | - Ulrike Gehring
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - James E Gern
- Departments of Pediatrics and Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Christine C Johnson
- Department of Public Health Sciences, Henry Ford Hospital & Health System, Detroit, Mich
| | - Suzanne Kennedy
- Department of Pediatrics, NC Children's Hospital, University of North Carolina, Chapel Hill, NC
| | - Petros Koutrakis
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Mass
| | - Brian Leaderer
- Yale School of Public Health, Yale School of Medicine, Yale School of Forestry and Environmental Studies, Center for Perinatal, Pediatric and Environmental Epidemiology (CPPEE), New Haven, Conn
| | | | - Augusto A Litonjua
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, Mass
| | - Geoffrey A Mueller
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC
| | - George T O'Connor
- Pulmonary Center, Boston University School of Medicine, Boston, Mass
| | - Dennis Ownby
- Division of Allergy-Immunology and Rheumatology, Department of Pediatrics, Augusta University, Augusta, Ga
| | - Wanda Phipatanakul
- Asthma, Allergy and Immunology, Boston Children's Hospital, Harvard Medical School, Boston, Mass
| | - Victoria Persky
- Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, Ill
| | - Matthew S Perzanowski
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY
| | - Clare D Ramsey
- Departments of Medicine and Community Health Sciences, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Päivi M Salo
- Division of Intramural Research, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC
| | - Julie M Schwaninger
- Division of Allergy, Immunology, and Transplantation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Md
| | - Joanne E Sordillo
- Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, Mass
| | - Avrum Spira
- Division of Computational Biomedicine, Department of Medicine, Boston University School of Medicine, Boston, Mass
| | - Shakira F Suglia
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Ga
| | - Alkis Togias
- Division of Allergy, Immunology, and Transplantation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Md
| | - Darryl C Zeldin
- Division of Intramural Research, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC
| | - Elizabeth C Matsui
- Division of Pediatric Allergy/Immunology, Johns Hopkins University, Baltimore, Md
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15
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Patterns of immune development in urban preschoolers with recurrent wheeze and/or atopy. J Allergy Clin Immunol 2017; 140:836-844.e7. [PMID: 28089873 DOI: 10.1016/j.jaci.2016.10.052] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 09/27/2016] [Accepted: 10/17/2016] [Indexed: 11/22/2022]
Abstract
BACKGROUND Disadvantaged urban children have high rates of allergic diseases and wheezing, which are diseases associated with type 2-biased immunity. OBJECTIVE We sought to determine whether environmental exposures in early life influence cytokine responses that affect the development of recurrent wheezing illnesses and allergic sensitization. METHODS A birth cohort of 560 urban families was recruited from neighborhoods with high rates of poverty, and 467 (83%) children were followed until 3 years of age. Cytokine responses were measured in blood cell samples obtained at birth (cord blood) and ages 1 and 3 years. Cytokine responses were examined in relation to personal characteristics and environmental exposures to allergens and endotoxin and to the development of allergic sensitization and recurrent wheeze assessed at age 3 years. RESULTS Cytokine responses generally increased with age, but responses at birth were poorly predictive for those at ages 1 and 3 years. Exposure to certain allergens (cockroach, mouse, dust mite) was significantly associated with enhanced cytokine responses at age 3 years, including IFN-α and IL-10 responses to certain stimulants and responses to phytohemagglutinin. Regarding the clinical outcomes, reduced LPS-induced IL-10 responses at birth were associated with recurrent wheeze. In contrast, reduced respiratory syncytial virus-induced IL-8 responses and increased 5'-cytosine-phosphate-guanine-3' (CpG)-induced IL-12p40 and allergen-induced IL-4 responses were associated with atopy. CONCLUSIONS These findings suggest that diverse biologic exposures, including allergens and endotoxin, in urban homes stimulate the development of cytokine responses in early life, and that cytokine responses to specific microbial and viral stimuli are associated with the development of allergic sensitization and recurrent wheeze.
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16
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Highly sensitive detection of lipopolysaccharides using an aptasensor based on hybridization chain reaction. Sci Rep 2016; 6:29524. [PMID: 27404735 PMCID: PMC4941573 DOI: 10.1038/srep29524] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 06/17/2016] [Indexed: 01/14/2023] Open
Abstract
Lipopolysaccharides (LPS), integral components of the outer membrane of all gram-negative bacteria, are closely associated with foodborne diseases such as fever, diarrhea and hypotension, and thus, the early and sensitive detection of LPS is necessary. In this study, an aptasensor assay based on hybridization chain reaction (HCR) was developed to detect LPS. Briefly, two complementary stable species of biotinylated DNA hairpins coexisted in solution until the introduction of a detection probe triggered a hybridization chain reaction cascade. The DNA conjugates specifically reacted with the LPS, which were captured by the ethanolamine aptamer attached to the reaction well surface. After optimizing the key reaction conditions, such as the reaction time of HCR, the amount of the capture probe and detection probes, the increase in the LPS concentration was readily measured by the optical density value, and a relatively low detection limit (1.73 ng/mL) was obtained, with a linear response range of 1–105 ng/mL. The approach presented herein introduced the use of an aptasensor for LPS discrimination and HCR for signal amplification, offering a promising option for detecting LPS.
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17
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Ghosh B, Lal H, Srivastava A. Review of bioaerosols in indoor environment with special reference to sampling, analysis and control mechanisms. ENVIRONMENT INTERNATIONAL 2015; 85:254-72. [PMID: 26436919 PMCID: PMC7132379 DOI: 10.1016/j.envint.2015.09.018] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 05/19/2023]
Abstract
Several tiny organisms of various size ranges present in air are called airborne particles or bioaerosol which mainly includes live or dead fungi and bacteria, their secondary metabolites, viruses, pollens, etc. which have been related to health issues of human beings and other life stocks. Bio-terror attacks in 2001 as well as pandemic outbreak of flue due to influenza A H1N1 virus in 2009 have alarmed us about the importance of bioaerosol research. Hence characterization i.e. identification and quantification of different airborne microorganisms in various indoor environments is necessary to identify the associated risks and to establish exposure threshold. Along with the bioaerosol sampling and their analytical techniques, various literatures revealing the concentration levels of bioaerosol have been mentioned in this review thereby contributing to the knowledge of identification and quantification of bioaerosols and their different constituents in various indoor environments (both occupational and non-occupational sections). Apart from recognition of bioaerosol, developments of their control mechanisms also play an important role. Hence several control methods have also been briefly reviewed. However, several individual levels of efforts such as periodic cleaning operations, maintenance activities and proper ventilation system also serve in their best way to improve indoor air quality.
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Affiliation(s)
- Bipasha Ghosh
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, India
| | - Himanshu Lal
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, India
| | - Arun Srivastava
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, India.
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18
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McGowan EC, Bloomberg GR, Gergen PJ, Visness CM, Jaffee KF, Sandel M, O'Connor G, Kattan M, Gern J, Wood RA. Influence of early-life exposures on food sensitization and food allergy in an inner-city birth cohort. J Allergy Clin Immunol 2014; 135:171-8. [PMID: 25129677 DOI: 10.1016/j.jaci.2014.06.033] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 06/04/2014] [Accepted: 06/30/2014] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Previous data suggest that food allergy (FA) might be more common in inner-city children; however, these studies have not collected data on both sensitization and clinical reactivity or early-life exposures. METHODS Children in the Urban Environment and Childhood Asthma birth cohort were followed through age 5 years. Household exposures, diet, clinical history, and physical examinations were assessed yearly; levels of specific IgE to milk, egg, and peanut were measured at 1, 2, 3, and 5 years of age. On the basis of sensitization (IgE ≥0.35 kU/L) and clinical history over the 5-year period, children were classified as having FA or being possibly allergic, sensitized but tolerant, or not allergic/not sensitized. RESULTS Five hundred sixteen children were included. Overall, 55.4% were sensitized (milk, 46.7%; egg, 31.0%; and peanut, 20.9%), whereas 9.9% were categorized as having FA (peanut, 6.0%; egg, 4.3%; and milk, 2.7%; 2.5% to >1 food). The remaining children were categorized as possibly allergic (17.0%), sensitized but tolerant (28.5%), and not sensitized (44.6%). Eighteen (3.5%) reported reactions to foods for which IgE levels were not measured. Food-specific IgE levels were similar in children with FA versus sensitized but tolerant children, except for egg, levels of which were higher in patients with FA at ages 1 and 2 years. FA was associated with recurrent wheeze, eczema, aeroallergen sensitization, male sex, breast-feeding, and lower endotoxin exposure in year 1 but not with race/ethnicity, income, tobacco exposure, maternal stress, or early introduction of solid foods. CONCLUSIONS Even given that this was designed to be a high-risk cohort, the cumulative incidence of FA is extremely high, especially considering the strict definition of FA that was applied and that only 3 common allergens were included.
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Affiliation(s)
- Emily C McGowan
- Department of Medicine, Division of Allergy and Clinical Immunology, Johns Hopkins University School of Medicine, and the Johns Hopkins Bloomberg School of Public Health, Baltimore, Md
| | - Gordon R Bloomberg
- Division of Allergy, Immunology, and Pulmonary Medicine, Washington University School of Medicine, St Louis, Mo
| | - Peter J Gergen
- National Institutes of Health, National Institute of Allergy and Infectious Diseases, Bethesda, Md
| | | | | | - Megan Sandel
- Department of Medicine, Division of Pediatric Primary Care, Boston University School of Medicine, Boston, Mass
| | - George O'Connor
- Department of Medicine, Division of Pulmonary, Allergy, Sleep, and Critical Care Medicine, Boston University School of Medicine, Boston, Mass
| | - Meyer Kattan
- Department of Pediatrics, Division of Pediatric Pulmonology, New York Presbyterian/Columbia University Medical Center, New York, NY
| | - James Gern
- Department of Pediatrics, Division of Allergy and Immunology, University of Wisconsin School of Medicine, Madison, Wis
| | - Robert A Wood
- Division of Allergy and Immunology, Johns Hopkins University School of Medicine, Department of Pediatrics, Baltimore, Md.
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Can Z, Wenjun L, Wen S, Minglu Z, Lingjia Q, Cuiping L, Fang T. Endotoxin contamination and control in surface water sources and a drinking water treatment plant in Beijing, China. WATER RESEARCH 2013; 47:3591-3599. [PMID: 23726695 DOI: 10.1016/j.watres.2013.04.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 02/21/2013] [Accepted: 04/07/2013] [Indexed: 06/02/2023]
Abstract
In this paper, endotoxin contamination was determined in treated water following each unit of a drinking water treatment plant (WTP) in Beijing, China and its source water (SW) from a long water diversion channel (Shijiazhuang-Beijing) originating from four reservoirs in Hebei province, China. The total-endotoxin activities in SW ranged from 21 to 41 EU/ml at five selected cross sections of the diversion channel. The total-endotoxin in raw water of the WTP ranged from 11 to 16 EU/ml due to dilution and pretreatment during water transportation from Tuancheng Lake to the WTP, and finished water of the WTP ranged from 4 to 10 EU/ml, showing a 49% decrease following the full-scale treatment process at the WTP. Compared with the 31% removal of free-endotoxin, the WTP removed up to 71% of bound-endotoxin in raw water. The traditional treatment processes (coagulation, sedimentation and filtration) in the WTP removed substantial amounts of total-endotoxin (up to 63%), while endotoxin activities increased after granular activated carbon (GAC) adsorption and chlorination. The total-endotoxin in the actual water was composed of free-endotoxin and bound-endotoxin (endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins). The endotoxin aggregates, bacteria-bound endotoxins and particle-attached endotoxins co-exist as suspended particles in water, and only the bacteria-bound endotoxins were correlated with bacterial cells suspended in water. The particle distribution of endotoxin aggregates in ultrapure water was also tested and the results showed that the majority (64-89%) of endotoxin aggregates had diameters <2 μm. The endotoxin contamination and control in treated water following each unit of the WTP processes and its SW from reservoirs are discussed and compared with regard to bacterial cell counts and particle characteristics, which were dependent, to a certain extent, on different flow rates and turbulence of the water environments.
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Affiliation(s)
- Zhang Can
- School of Environment, Tsinghua University, Beijing 100084, China.
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20
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Ownby DR, Peterson EL, Wegienka G, Woodcroft KJ, Nicholas C, Zoratti E, Johnson CC. Are cats and dogs the major source of endotoxin in homes? INDOOR AIR 2013; 23:219-226. [PMID: 23167871 PMCID: PMC4005287 DOI: 10.1111/ina.12016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Accepted: 11/13/2012] [Indexed: 05/31/2023]
Abstract
UNLABELLED Previous studies have suggested that exposure to cats and dogs during early childhood reduces the risk of allergic disease, possibly by increasing home endotoxin exposure. This study asked the question of whether cats and dogs are the dominant influence on dust endotoxin concentrations in homes after considering other variables reportedly associated with endotoxin. The presence of cats or dogs in homes, household and home characteristics, and dust endotoxin concentrations from 5 locations were assessed in 966 urban and suburban homes. Whether considered together as pets or as cats and dogs separately, the presence of cats and dogs significantly contributed to living room and bedroom floor endotoxin concentrations, but not to bed endotoxin concentrations. However, the two variables consistently related to endotoxin in all home sites were the home occupant density (occupants/room) and cleanliness of the home. Our data suggest that reducing occupant density and improving home cleanliness would reduce home endotoxin concentrations more than removing pet cats or dogs from the home. PRACTICAL IMPLICATIONS Many studies have shown that early childhood exposure to indoor cats or dogs is associated with a reduced risk of later allergic disease and asthma. An important question is whether alteration in allergic risk associated with cat and dog exposure results from increased endotoxin exposure or from some other associated exposure. Our findings show that cats and dogs are not the dominant source of endotoxin in homes; rather, the density of human occupation and poor cleaning contribute more consistently to higher home endotoxin concentrations especially in the beds.
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Affiliation(s)
- D R Ownby
- Division of Allergy, Immunology, Rheumatology, Department of Pediatrics, Georgia Health Sciences University, Augusta, GA 30912-3790, USA.
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Toossi Z, Funderburg NT, Sirdeshmuk S, Whalen CC, Nanteza MW, Johnson DF, Mayanja-Kizza H, Hirsch CS. Systemic immune activation and microbial translocation in dual HIV/tuberculosis-infected subjects. J Infect Dis 2013; 207:1841-9. [PMID: 23479321 DOI: 10.1093/infdis/jit092] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Systemic immune activation is a strong predictor of progression of human immunodeficiency virus type 1 (HIV-1) disease and a prominent feature of infection with Mycobacterium tuberculosis. OBJECTIVE To understand the role of systemic immune activation and microbial translocation in HIV/tuberculosis dually infected patients over the full spectrum of HIV-1 immunodeficiency, we studied circulating sCD14 and lipopolysaccharide (LPS) and their relationship to HIV-1 activity. METHODS Two cohorts of HIV/tuberculosis subjects defined by CD4 T-cell count at time of diagnosis of tuberculosis were studied: those with low (<350/μL) and those with high (≥ 350/μL) CD4 T-cell count. Circulating soluble CD14 (sCD14) and LPS were assessed. RESULTS Levels of sCD14 were higher in HIV/tuberculosis with high (≥ 350/μL) as compared to low CD4 T-cell count (P < .001). Whereas sCD14 levels remained elevated in HIV/tuberculosis subjects with lower CD4 T-cell counts despite treatment of tuberculosis, in HIV/tuberculosis patients with higher CD4 T-cell count (≥ 350/μL), levels declined regardless of whether highly active antiretroviral therapy (HAART) was included with the anti-tuberculosis regimen. Circulating LPS levels in HIV/tuberculosis patients with CD4 T-cell count ≥ 350/μL were unaffected by treatment of tuberculosis with or without HAART. CONCLUSION During HIV/tuberculosis, systemic immune activation is dissociated from microbial translocation. Changes in circulating sCD14 and LPS are dependent on CD4 T-cell count.
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Affiliation(s)
- Zahra Toossi
- Case Western Reserve University, Cleveland, Ohio, USA.
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Crist RM, Grossman JH, Patri AK, Stern ST, Dobrovolskaia MA, Adiseshaiah PP, Clogston JD, McNeil SE. Common pitfalls in nanotechnology: lessons learned from NCI's Nanotechnology Characterization Laboratory. Integr Biol (Camb) 2013; 5:66-73. [PMID: 22772974 PMCID: PMC3499664 DOI: 10.1039/c2ib20117h] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The Nanotechnology Characterization Laboratory's (NCL) unique set-up has allowed our lab to handle and test a variety of nanoparticle platforms intended for the delivery of cancer therapeutics and/or imaging contrast agents. Over the last six years, the NCL has characterized more than 250 different nanomaterials from more than 75 different investigators. These submitted nanomaterials stem from a range of backgrounds and experiences, including government, academia and industry. This has given the NCL a unique and valuable opportunity to observe trends in nanoparticle safety and biocompatibility, as well as note some of the common mistakes and oversights of nanoformulation. While not exhaustive, this article aims to share some of the most common pitfalls observed by the NCL as they relate to nanoparticle synthesis, purification, characterization and analysis.
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Affiliation(s)
- Rachael M. Crist
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Jennifer Hall Grossman
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Anil K. Patri
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Stephan T. Stern
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Marina A. Dobrovolskaia
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Pavan P. Adiseshaiah
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Jeffrey D. Clogston
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
| | - Scott E. McNeil
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD 21702
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Pulmonary function reductions among potentially susceptible subgroups of agricultural workers in Colorado and Nebraska. J Occup Environ Med 2012; 54:632-41. [PMID: 22576462 DOI: 10.1097/jom.0b013e31824d2e1c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Organic dust inhalation has been associated with adverse respiratory responses among agricultural workers. We evaluated factors that may confer increased susceptibility to these health effects. METHODS We quantified personal work shift exposures to inhalable dust, endotoxin, and its 3-hydroxy fatty acid constituents, and evaluated changes in pulmonary function among 137 grain elevator, cattle feedlot, dairy, and corn farm workers. RESULTS Increased dust exposure was associated with work shift reductions in lung function. Although interpretation is limited because of small samples, a suggestion of stronger exposure-response relationships was observed among smokers, as well as workers reporting pesticide/herbicide application, asthma, or allergies, and those with genetic polymorphisms (TLR4) (Pinteraction ≤ 0.05). CONCLUSIONS A better understanding of factors leading to increased susceptibility of adverse respiratory outcomes is needed to optimize exposure reduction strategies and develop more comprehensive wellness programs.
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Duquenne P, Marchand G, Duchaine C. Measurement of endotoxins in bioaerosols at workplace: a critical review of literature and a standardization issue. ACTA ACUST UNITED AC 2012; 57:137-72. [PMID: 23002277 DOI: 10.1093/annhyg/mes051] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Endotoxins are lipopolysaccharides found in the outer membrane of most Gram-negative bacteria and cyanobacteria. Worker exposure to endotoxins has been shown in a number of work situations and is associated with both respiratory and systemic pathologies. The lack of an occupational exposure limit is mainly due to the absence of a standard protocol at the international level for sampling and analyzing airborne endotoxins. The bibliographic review in this article takes an exhaustive look at the current knowledge on measuring airborne endotoxins. It shows that, despite several reference documents at the international level, the methods used to measure endotoxin exposure differ considerably from one laboratory to another. Standardization is necessary to reduce interlaboratory variability and, ultimately, to improve the use of interstudy data. The bibliographic review presents the current status of standardization for airborne endotoxin measurement methods in the workplace and summarizes areas for further research. This article is both a reference document for all operators wishing to use such methods and a working document to build international consensus around the measurement of airborne endotoxins.
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Affiliation(s)
- Philippe Duquenne
- Laboratoire de Métrologie des Aérosols, Institut National de Recherche et de Sécurité, Vandoeuvre-Les-Nancy, France.
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Occupational exposure to particulate matter and endotoxin for California dairy workers. Int J Hyg Environ Health 2012; 216:56-62. [PMID: 22579491 DOI: 10.1016/j.ijheh.2012.04.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Revised: 03/14/2012] [Accepted: 04/10/2012] [Indexed: 11/23/2022]
Abstract
Occupational exposure of dairy workers to particulate matter (PM) and endotoxin has been considered by some to be of potential concern. This paper reports personal exposure concentrations of PM (μg/m3) and endotoxin (EU/m3) for 226 workers from 13 California dairies. Arithmetic mean personal concentrations for PM2.5, inhalable PM and endotoxin were 48 μg/m3 (N = 222), 987 μg/m3 (N = 225) and 453 EU/m3 (N = 225), respectively. Using mixed effects models, time spent re-bedding of freestall barns versus any other job conducted on a dairy led to the highest exposure for PM2.5, inhalable PM, and endotoxin. Personal exposure concentrations were found to be greater than those reported for ambient area based concentrations at the same dairies. A pseudo R-square approach revealed that one area based measure combined with time spent performing tasks explained a significant portion of variation in personal exposure concentrations.
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Garcia J, Bennett DH, Tancredi DJ, Schenker MB, Mitchell DC, Reynolds SJ, Silva R, Dooley GP, Mehaffy J, Mitloehner FM. Characterization of endotoxin collected on California dairies using personal and area-based sampling methods. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2012; 9:580-591. [PMID: 22946649 DOI: 10.1080/15459624.2012.713301] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Endotoxin, found in the cell wall of gram negative bacteria, is an important contributor to the biological activity of agriculture particulate matter (PM). We analyzed endotoxin in PM collected on 13 California dairies and from the breathing zone of 226 workers during the summer months of 2008. Two particle size fractions were measured: PM(2.5) and inhalable PM. Recombinant factor C assays were used to analyze biologically active endotoxin, while gas chromatography coupled with mass spectrometry in tandem was used to quantify total lipopolysaccharide. Biologically active endotoxin concentrations in the inhalable PM size fraction from area-based samples ranged from 11-2095 EU/m(3) and from 45-2061 EU/m(3) for personal samples. Total endotoxin in the inhalable PM size fraction ranged from 75-10,166 pmol/m(3) for area-based samples and 34-11,689 pmol/m(3) for personal samples. Area-based geometric mean concentrations for biologically active endotoxin and total endotoxin in PM(2.5) and inhalable PM size fractions were 3 EU/m(3), 149 EU/m(3), 60 pmol/m(3), and 515 pmol/m(3), respectively. Personal geometric mean concentrations in the inhalable PM size fraction were 334 EU/m(3), and 1178 pmol/m(3). Biologically active and total endotoxin concentration variation was best explained by meteorological data, wind speed, relative humidity, and dairy waste management practices. Differences in endotoxin concentration and composition were found across locations on the dairy.
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Affiliation(s)
- John Garcia
- Department of Public Health Sciences and Center for Health and the Environment, University of California Davis, Davis, CA, USA
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Choudhry AH, Reynolds SJ, Mehaffy J, Douphrate DI, Gilmore K, Levin JL, Nonnenmann MW. Evaluation of parlor cleaning as an intervention for decreased occupational exposure to dust and endotoxin among dairy parlor workers--a pilot study. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2012; 9:D136-D140. [PMID: 22702233 DOI: 10.1080/15459624.2012.691410] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Affiliation(s)
- Aika H Choudhry
- Department of Occupational Health Sciences, University of Texas Health Science Center at Tyler, Tyler, Texas, USA
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McKenzie JH, Alwis KU, Sordillo JE, Kalluri KS, Milton DK. Evaluation of lot-to-lot repeatability and effect of assay media choice in the recombinant Factor C assay. ACTA ACUST UNITED AC 2011; 13:1739-45. [PMID: 21552635 DOI: 10.1039/c1em10035a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Measurement of environmental endotoxin exposures is complicated by variability encountered using current biological assay methods arising in part from lot-to-lot variability of the Limulus-amebocyte lysate (LAL) reagents. Therefore, we investigated the lot-to-lot repeatability of commercially available recombinant Factor C (rFC) kits as an alternative to LAL. Specifically, we compared endotoxin estimates obtained from rFC assay of twenty indoor dust samples, using four different extraction and assay media, to endotoxin estimates previously obtained by Limulus amebocyte lysate (LAL) assay and amounts of 3-hydroxy fatty acids (3-OHFA) in lipopolysaccharide (LPS) using gas-chromatography mass spectroscopy (GC-MS). We found that lot-to-lot variability of the rFC assay kits does not significantly alter endotoxin estimates in house dust samples when performed using three of the four assay media tested and that choice of assay media significantly altered endotoxin estimates obtained by rFC assay of house dust samples. Our findings demonstrate lot-to-lot reproducibility of rFC assay of environmental samples and suggest that use of rFC assay performed with Tris buffer or water as the extraction and assay medium for measurement of endotoxin in dust samples may be a suitable choice for developing a standardized methodology.
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Affiliation(s)
- Jennifer Helen McKenzie
- Biomedical Engineering and Biotechnology Program, University of Massachusetts, Lowell, MA, USA
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Wood RA, Bloomberg GR, Kattan M, Conroy K, Sandel MT, Dresen A, Gergen PJ, Gold DR, Schwarz JC, Visness CM, Gern JE. Relationships among environmental exposures, cord blood cytokine responses, allergy, and wheeze at 1 year of age in an inner-city birth cohort (Urban Environment and Childhood Asthma study). J Allergy Clin Immunol 2011; 127:913-9.e1-6. [PMID: 21333343 PMCID: PMC3070829 DOI: 10.1016/j.jaci.2010.12.1122] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 12/17/2010] [Accepted: 12/22/2010] [Indexed: 10/18/2022]
Abstract
BACKGROUND The Urban Environment and Childhood Asthma study was established to investigate the immunologic and environmental causes of asthma in inner-city children. OBJECTIVE We sought to evaluate potential atopic outcomes in the first 12 months and their relationships to environmental exposures and immune development. METHODS A birth cohort of 560 children with at least 1 parent with allergy or asthma was established in Baltimore, Boston, New York, and St Louis. Wheezing is assessed every 3 months, allergen-specific IgE yearly, and mononuclear cell cytokine responses at birth and yearly; environmental assessments include dust allergen and endotoxin, maternal stress, and indoor nicotine and nitrogen dioxide levels. RESULTS Key outcomes in the first year include wheeze in 49%, 2 or more episodes of wheeze in 23%, eczema in 30%, and detectable IgE to milk, egg, and/or peanut in 32% and to cockroach in 4%. Household dust revealed levels of greater than 2 μg/g to cockroach in 40%, mite in 19%, cat in 25%, and mouse in 29%, and 66% of homes housed at least 1 smoker. Positive associations were detected between multiple wheeze and cotinine levels, maternal stress, and maternal depression, whereas cytokine responses to a variety of innate, adaptive, and mitogenic stimuli were inversely related to eczema. CONCLUSIONS This high-risk cohort of inner-city infants is exhibiting high rates of wheeze, eczema, and allergic sensitization. Low cytokine responses at birth might be a risk factor for eczema, whereas a variety of adverse environmental exposures contribute to the risk of wheezing in infancy. These findings provide evidence of specificity in the interactions between immune development, environmental exposures, and the development of early features that might predict future asthma.
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Affiliation(s)
- Robert A Wood
- Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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Sordillo JE, Alwis UK, Hoffman E, Gold DR, Milton DK. Home characteristics as predictors of bacterial and fungal microbial biomarkers in house dust. ENVIRONMENTAL HEALTH PERSPECTIVES 2011; 119:189-95. [PMID: 20965804 PMCID: PMC3040605 DOI: 10.1289/ehp.1002004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2010] [Accepted: 10/21/2010] [Indexed: 05/03/2023]
Abstract
BACKGROUND Measurement of fungal and bacterial biomarkers can be costly, but it is not clear whether home characteristics can be used as a proxy of these markers, particularly if the purpose is to differentiate specific classes of biologic exposures that have similar sources but may have different effects on allergic disease risk. OBJECTIVE We evaluated home characteristics as predictors of multiple microbial biomarkers, with a focus on common and unique determinants and with attention to the extent of their explanatory ability. METHODS In 376 Boston-area homes enrolled in a cohort study of home exposures and childhood asthma, we assessed the relationship between home characteristics gathered by questionnaire and measured gram-negative bacteria (GNB) (endotoxin and C10:0, C12:0, and C14:0 3-hydroxy fatty acids), gram-positive bacteria (GPB) (N-acetyl muramic acid), and fungal biomarkers [ergosterol and (1→6) branched, (1→3) β-D glucans] in bed and family room dust. RESULTS Home characteristics related to dampness were significant predictors of all microbial exposures; water damage or visible mold/mildew in the home was associated with a 20-66% increase in GNB levels. Report of cleaning the bedroom at least once a week was associated with reduced GNB, GPB, and fungi. Presence of dogs or cats predicted increases in home bacteria or fungi. The proportion of variance in microbial biomarkers explained by home characteristics ranged from 4.2% to 19.0%. CONCLUSIONS Despite their associations with multiple microbial flora, home characteristics only partially explain the variability in microbial biomarker levels and cannot substitute for specific microbial measurements in studies concerned with distinguishing effects of specific classes of microbes.
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Affiliation(s)
- Joanne E Sordillo
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
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Evaluation of the Limulus amebocyte lysate and recombinant factor C assays for assessment of airborne endotoxin. Appl Environ Microbiol 2010; 76:4988-95. [PMID: 20525858 DOI: 10.1128/aem.00527-10] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
As a potent inflammatory agent, endotoxin is a key analyte of interest for studies of lung ailments in domestic environments and occupational settings with organic dust. A relatively unexplored advance in endotoxin exposure assessment is the use of recombinant factor C (rFC) from the Limulus pathway in a fluorometric assay. In this study, we compared airborne endotoxin concentrations in laboratory- and field-collected parallel air samples using the kinetic Limulus amebocyte lysate (LAL) assay and the rFC assay. Air sampling was performed using paired Institute of Occupational Medicine (IOM) samplers, Button samplers, closed-face cassettes, and cyclone samplers. Field sampling was performed in 10 livestock production facilities, including those housing swine, chicken, turkey, dairy cows, cattle, and horses. Laboratory sampling was performed in exposure chambers using resuspended airborne dust collected in five livestock facilities. Paired samples were extracted in pyrogen-free water with 0.05% Tween 20 and analyzed using LAL and rFC assays. In 402 field sample pairs there was excellent agreement between endotoxin concentrations determined by LAL and rFC (r = 0.93; P < 0.0001). In 510 laboratory sample pairs there was also excellent agreement between the two assays (r = 0.86; P < 0.0001). Correlations for subgroups of facility or dust type ranged from 0.65 to 0.96. Mixed-model analysis of variance (ANOVA) for the field studies showed significant interactions of facility-sampler and facility-assay. rFC/LAL ratios of the geometric means were 0.9 to 1.14 for the samplers (not significantly different from 1.0). The data from this study demonstrate that the LAL assay and the rFC assay return similar estimates of exposure in livestock facilities. Both methods provided suitable lower limits of detection such that all but 19 of 1,824 samples were quantifiable.
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Ownby DR, Peterson EL, Williams LK, Zoratti EM, Wegienka GR, Woodcroft KJ, Joseph CLM, Johnson CC. Variation of dust endotoxin concentrations by location and time within homes of young children. Pediatr Allergy Immunol 2010; 21:533-40. [PMID: 20088861 PMCID: PMC4025918 DOI: 10.1111/j.1399-3038.2009.00918.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Endotoxin may affect the development of allergic disease in childhood but little is known about endotoxin variation within homes. We sought to determine endotoxin concentration agreement within homes when five locations were each sampled twice 5 months apart. Endotoxin was measured using the recombinant Limulus factor C assay in dust samples from 585 homes of children enrolled in a prospective study and again in 335 homes 5 months later. The five locations sampled in each home were the child's bedroom floor, child's bed, mother's bedroom floor, mother's bed and living room floor. Concentrations of 4 allergens (Can f 1, Fel d 1, Der f 1 and Bla g 2) were also measured from the child's bedroom floor. In pair-wise comparisons, endotoxin concentrations in all locations within each home were significantly different from all other locations (p < 0.001) except for the child's and mother's bedroom floors (p = 0.272). Spearman correlations between endotoxin concentrations from the different locations were all statistically significant (p < 0.05) but of modest magnitude (r = 0.24-0.54). Similarly, correlations at each site over the 5 month observation interval were statistically significant but modest (r = 0.17-0.44). Pets and season of the year did not affect correlations, although correlations were lower if the floor was not carpeted. Endotoxin concentrations at all locations were minimally correlated with allergen concentrations in both negative and positive directions (r = -0.12 to 0.12). We conclude that a single measurement of endotoxin from a home dust sample provides an imprecise estimate of dust endotoxin concentrations in other locations within the home and over a relatively short observation interval.
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Affiliation(s)
- Dennis R Ownby
- Department of Allergy and Immunology, Medical College of Georgia, Augusta, GA, USA.
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Sordillo JE, Hoffman EB, Celedón JC, Litonjua AA, Milton DK, Gold DR. Multiple microbial exposures in the home may protect against asthma or allergy in childhood. Clin Exp Allergy 2010; 40:902-10. [PMID: 20412140 DOI: 10.1111/j.1365-2222.2010.03509.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Experimental animal data on the gram-negative bacterial (GNB) biomarker endotoxin suggest that persistence, dose, and timing of exposure are likely to influence its effects on allergy and wheeze. In epidemiologic studies, endotoxin may be a sentinel marker for a microbial milieu, including gram-positive bacteria (GPB) as well as GNB, that may influence allergy and asthma through components (pathogen-associated molecular patterns) that signal through innate Toll-like receptor pathways. OBJECTIVE To determine the influence of current GNB and GPB exposures on asthma and allergic sensitization in school-aged children. METHODS We examined the relationship between bacterial biomarkers and current asthma and allergic sensitization in 377 school-aged children in a birth cohort study. We then evaluated the effects of school-aged endotoxin, after controlling for exposure in early life. RESULTS Exposure to GNB was inversely associated with asthma and allergic sensitization at school age [for >median endotoxin: prevalence odds ratio (POR)=0.34, 95% CI=0.2-0.7, for current asthma and prevalence ratio=0.77, 95% CI=0.6-0.97, for allergic sensitization]. In contrast, elevated GPB in the bed was inversely associated with current asthma (POR=0.41, 95% CI=0.2-0.9) but not with allergic sensitization (POR=1.07, 95% CI=0.8-1.4). School-aged endotoxin exposure remained protective in models for allergic disease adjusted for early-life endotoxin. CONCLUSION Both GNB and GPB exposures are associated with decreased asthma symptoms, but may act through different mechanisms to confer protection. Endotoxin exposure in later childhood is not simply a surrogate of early-life exposure; it has independent protective effects on allergic disease.
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Burch JB, Svendsen E, Siegel PD, Wagner SE, von Essen S, Keefe T, Mehaffy J, Martinez AS, Bradford M, Baker L, Cranmer B, Saito R, Tessari J, Linda P, Andersen C, Christensen O, Koehncke N, Reynolds SJ. Endotoxin exposure and inflammation markers among agricultural workers in Colorado and Nebraska. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2010; 73:5-22. [PMID: 19953416 DOI: 10.1080/15287390903248604] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The adverse respiratory effects of agricultural dust inhalation are mediated in part by endotoxin, a constituent of gram-negative bacterial cell walls. This study quantified personal work-shift exposures to inhalable dust, endotoxin, and its reactive 3-hydroxy fatty acid (3-OHFA) constituents among workers in grain elevators, cattle feedlots, dairies, and on corn farms. Exposures were compared with post-work-shift nasal lavage fluid inflammation markers and respiratory symptoms. Breathing-zone personal air monitoring was performed over one work shift to quantify inhalable dust (Institute of Medicine samplers), endotoxin (recombinant factor C [rFC] assay), and 3-OHFA (gas chromatography/mass spectrometry). Post-shift nasal lavage fluids were assayed for polymorphonuclear neutrophils (PMN), myeloperoxidase (MPO), interleukin 8 (IL-8), albumin, and eosinophilic cation protein (ECP) concentrations. The geometric mean (GSD) of endotoxin exposure (rFC assay) among the 125 male participants was 888 +/- (6.5) EU/m(3), and 93% exceeded the proposed exposure limit (50 EU/m(3)). Mean PMN, MPO, albumin, and ECP levels were two- to threefold higher among workers in the upper quartile of 3-OHFA exposure compared to the lowest exposure quartile. Even numbered 3-OHFA were most strongly associated with nasal inflammation. Symptom prevalence was not elevated among exposed workers, possibly due to endotoxin tolerance or a healthy worker effect in this population. This is the first study to evaluate the relationship between endotoxin's 3-OHFA constituents in agricultural dust and nasal airway inflammation. More research is needed to characterize the extent to which these agents contribute to respiratory disease among agricultural workers.
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Affiliation(s)
- James B Burch
- Department of Epidemiology and Biostatistics, Cancer Prevention and Control Program, and Center for Colon Cancer Research, University of South Carolina, Columbia, SC 29208, USA.
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Saito R, Cranmer BK, Tessari JD, Larsson L, Mehaffy JM, Keefe TJ, Reynolds SJ. Recombinant factor C (rFC) assay and gas chromatography/mass spectrometry (GC/MS) analysis of endotoxin variability in four agricultural dusts. ACTA ACUST UNITED AC 2009; 53:713-22. [PMID: 19638393 DOI: 10.1093/annhyg/mep052] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Endotoxin exposure is a significant concern in agricultural environments due to relatively high exposure levels. The goals of this study were to determine patterns of 3-hydroxy fatty acid (3-OHFA) distribution in dusts from four types of agricultural environments (dairy, cattle feedlot, grain elevator, and corn farm) and to evaluate correlations between the results of gas chromatography/mass spectrometry (GC/MS) analysis (total endotoxin) and biological recombinant factor C (rFC) assay (free bioactive endotoxin). An existing GC/MS-MS method (for house dust) was modified to reduce sample handling and optimized for small amount (<1 mg) of agricultural dusts using GC/EI-MS. A total of 134 breathing zone samples using Institute of Occupational Medicine (IOM) inhalable samplers were collected from agricultural workers in Colorado and Nebraska. Livestock dusts contained approximately two times higher concentrations of 3-OHFAs than grain dusts. Patterns of 3-OHFA distribution and proportion of each individual 3-OHFA varied by dust type. The rank order of Pearson correlations between the biological rFC assay and the modified GC/EI-MS results was feedlot (0.72) > dairy (0.53) > corn farm (0.33) > grain elevator (0.11). In livestock environments, both odd- and even-numbered carbon chain length 3-OHFAs correlated with rFC assay response. The GC/EI-MS method should be especially useful for identification of specific 3-OHFAs for endotoxins from various agricultural environments and may provide useful information for evaluating the relationship between bacterial exposure and respiratory disease among agricultural workers.
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Affiliation(s)
- Rena Saito
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA.
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Gern JE, Visness CM, Gergen PJ, Wood RA, Bloomberg GR, O'Connor GT, Kattan M, Sampson HA, Witter FR, Sandel MT, Shreffler WG, Wright RJ, Arbes SJ, Busse WW. The Urban Environment and Childhood Asthma (URECA) birth cohort study: design, methods, and study population. BMC Pulm Med 2009; 9:17. [PMID: 19426496 PMCID: PMC2689166 DOI: 10.1186/1471-2466-9-17] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Accepted: 05/08/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The incidence and morbidity of wheezing illnesses and childhood asthma is especially high in poor urban areas. This paper describes the study design, methods, and population of the Urban Environment and Childhood Asthma (URECA) study, which was established to investigate the immunologic causes of asthma among inner-city children. METHODS AND RESULTS URECA is an observational prospective study that enrolled pregnant women in central urban areas of Baltimore, Boston, New York City, and St. Louis and is following their offspring from birth through age 7 years. The birth cohort consists of 560 inner-city children who have at least one parent with an allergic disease or asthma, and all families live in areas in which at least 20% of the population has incomes below the poverty line. In addition, 49 inner-city children with no parental history of allergies or asthma were enrolled. The primary hypothesis is that specific urban exposures in early life promote a unique pattern of immune development (impaired antiviral and increased Th2 responses) that increases the risk of recurrent wheezing and allergic sensitization in early childhood, and of asthma by age 7 years. To track immune development, cytokine responses of blood mononuclear cells stimulated ex vivo are measured at birth and then annually. Environmental assessments include allergen and endotoxin levels in house dust, pre- and postnatal maternal stress, and indoor air nicotine and nitrogen dioxide. Nasal mucous samples are collected from the children during respiratory illnesses and analyzed for respiratory viruses. The complex interactions between environmental exposures and immune development will be assessed with respect to recurrent wheeze at age 3 years and asthma at age 7 years. CONCLUSION The overall goal of the URECA study is to develop a better understanding of how specific urban exposures affect immune development to promote wheezing illnesses and asthma.
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Affiliation(s)
- James E Gern
- University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | - Peter J Gergen
- National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Robert A Wood
- Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | | | - Meyer Kattan
- Columbia University College of Physicians and Surgeons, New York, NY, USA
| | | | - Frank R Witter
- Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | | | | | - Samuel J Arbes
- Rho Federal Systems Division, Inc., Chapel Hill, NC, USA
| | - William W Busse
- University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
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Corticosteroid-resistant asthma is associated with classical antimicrobial activation of airway macrophages. J Allergy Clin Immunol 2008; 122:550-9.e3. [PMID: 18774390 DOI: 10.1016/j.jaci.2008.07.007] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2008] [Revised: 07/02/2008] [Accepted: 07/08/2008] [Indexed: 11/23/2022]
Abstract
BACKGROUND The cause of corticosteroid-resistant (CR) asthma is unknown. OBJECTIVE We sought to perform gene microarray analyses by using bronchoalveolar lavage (BAL) cells from well-characterized subjects with CR asthma and subject with corticosteroid-sensitive (CS) asthma to elucidate the differential expression of genes that contribute to the development of corticosteroid resistance. METHODS The patients were characterized as having CR or CS asthma based on FEV(1) percent predicted improvement after a 1-week course of oral prednisone. Expression of selected gene targets was verified by means of real-time PCR and ELISA. RESULTS Microarray analyses demonstrated significantly higher levels (>3-fold increase, P < .05) of transcripts for TNF-alpha, IL-1 alpha, IL-1 beta, IL-6, CXCL1, CXCL2, CXCL3, CXCL8 (IL-8), CCL3, CCL4, and CCL20 in BAL cells of subjects with CR asthma. These findings, confirmed by means of RT-PCR in additional BAL samples, were consistent with classical macrophage activation by bacterial products. In contrast, markers of alternatively activated macrophages, arginase I and CCL24, were decreased. Genes associated with activation of the LPS signaling pathway (early growth response 1, dual-specificity phosphatase 2, molecule possessing ankyrin repeats induced by LPS, and TNF-alpha-induced protein 3) were significantly increased in BAL samples from subjects with CR asthma (P < .05). These patients had significantly higher amounts (1444.0 +/- 457.3 pg/mg total protein) of LPS in BAL fluid than seen in subjects with CS asthma (270.5 +/- 216.0 pg, P < .05), as detected by using the LAL assay and confirmed by means of gas chromatographic/mass spectrometric analysis. Prolonged exposure to LPS induced functional steroid resistance to dexamethasone in normal human monocytes, as demonstrated by persistently increased IL-6 levels in the presence of dexamethasone. CONCLUSIONS Classical macrophage activation and induction of LPS signaling pathways along with high endotoxin levels detected in BAL fluid from subjects with CR asthma suggest that LPS exposure might contribute to CR asthma.
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