Development and validation of a chitin assay for environmental samples

环境样品甲壳素测定的开发和验证

• 批准号: 8289965
• 负责人: Christine Anne Rogers
• 金额: $ 39.74万
• 依托单位: UNIVERSITY OF MASSACHUSETTS AMHERST
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-12 至 2015-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8289965
• 关键词: Acetylglucosamine; Adjuvant; Air; Allergens; Allergic; Allergic Disease; Alternaria; Archives; Asthma; Binding; Binding Proteins; Biological Assay; Cellulose; Characteristics; Chitin; Chitinase; Chitosan; Cohort Studies; Complex; Data; Dermatophagoides farinae antigen f 1; Detection; Development; Dictyoptera; Disease; Dose; Dust; Early treatment; Environment; Environmental Exposure; Environmental Impact; Environmental Monitoring; Environmental Pollution; Enzyme-Linked Immunosorbent Assay; Enzymes; Exposure to; Extrinsic asthma; Future; Genes; Genetic; Genetic Polymorphism; Glucans; Goals; Horseradish Peroxidase; House Dust; Human; Immune; Individual; Inflammation; Intervention; Lead; Legal patent; Ligands; Link; Lung; Measures; Molecular; Mus; Organism; Outcomes Research; Pathogenesis; Pathway interactions; Pattern; Play; Polymers; Polysaccharides; Population; Prevalence; Production; Proteins; Protocols documentation; Public Health; Publishing; Reporting; Research; Role; Sampling; Specificity; Symptoms; Testing; Toll-Like Receptor 2; Validation; Vibrio parahaemolyticus; Work; air sampling; base; eosinophilic inflammation; fungus; gene environment interaction; microbial; pathogen; prevent; pyroglyphid; sensor

DESCRIPTION (provided by applicant): Asthma is a complex disease influenced by both genetics and environmental exposures, but the pathogenesis still remains unclear. Chitinase and chitinase-like proteins (CLPs) recently identified in humans have been found to play a significant role in both inflammation and asthma. Chitin - the ligand of these functional and non-functional enzymes -is a pathogen-associated molecular pattern that induces innate immune pathways, induces a Th2-type eosinophilic inflammation, and can act as an adjuvant for sensitization to bystander proteins. Chitin is an insoluble, long chain polymer of ¿1-4-N-acetyl-D-glucosamine and is a structural component of common indoor organisms such as dust mites, cockroaches, and fungi that are known asthma triggers. Chitin will be common in the environment where these organisms are abundant. Exposure to elevated levels of fungi in individuals with specific polymorphisms in a chitinase gene (CHIT1) is associated with increased asthma symptoms, strongly implicating a gene by environment interaction. Increasing evidence suggests both chitinases and chitin play a significant role in asthma, hence it is critically important to evaluate the impact of environmental chitin exposure on asthmatic populations. However, there is currently no way to directly assess chitin loads in the indoor environment since there is no assay available to do so, as there is for indoor allergens. The lack of a chitin specific assay is a critical barrier to our ability to assess the extent to which chitin exposure i contributing to the exacerbation and development of asthma. The long-term goal of the research is to understand the role of airborne microbial exposures (and components of them e.g. chitin) in the development and exacerbation of asthma. Our objective is to develop an ELISA assay for quantifying chitin in environmental samples from air or dust. We will systematically examine the specificities of currently available chitin-binding proteins, choose the most optimal, and examine its specificity for further development in an ELISA assay. We will develop a protocol for testing environmental samples with issues unique to handling and detection of insoluble chitin. Finally we will use the new chitin assay on archived dust samples from previous cohort studies and will compare chitin content with existing measures of chitin-containing organisms (culturable fungi) and their allergens such as Der p1 and Der f1 from dust mites, Bla g1 from cockroach, and Alt a1 from Alternaria alternata. The successful outcome of this research and the production of a well characterized chitin environmental assay will have a considerable impact on the field, allowing it to advance in exploring the extent to which chitin exposure has an impact on asthma exacerbation and development and the extent of any gene - environment interaction. PUBLIC HEALTH RELEVANCE: Asthma is increasing in prevalence and is strongly associated with a variety of environmental exposures. This project will develop a new environmental assay for chitin that will allow future assessments of its role in the development and progression of allergic sensitization and asthma that, if significant, could lead to new public health interventions to reduce allergic disease.

描述（申请人提供）：哮喘是一种受遗传和环境暴露影响的复杂疾病，但发病机制仍不清楚。几丁质酶和几丁质酶样蛋白（CLP）最近在人类中发现，已被发现在炎症和哮喘中发挥重要作用。几丁质-这些功能性和非功能性酶的配体-是病原体相关的分子模式，其诱导先天性免疫途径，诱导Th 2型嗜酸性粒细胞炎症，并且可以充当对旁观者蛋白致敏的佐剂。甲壳素是一种不溶性的长链聚合物，由1-4-N-乙酰基-D-葡萄糖胺组成，是常见的室内生物体的结构成分，如尘螨、蟑螂和真菌，它们是已知的哮喘诱因。甲壳素在这些生物丰富的环境中将是常见的。在几丁质酶基因（CHIT 1）具有特定多态性的个体中暴露于高水平的真菌与哮喘症状增加相关，强烈暗示基因与环境相互作用。越来越多的证据表明几丁质酶和几丁质在哮喘中起重要作用，因此评估环境几丁质暴露对哮喘人群的影响至关重要。然而，目前还没有办法直接评估室内环境中的几丁质负荷，因为没有可用的测定方法来这样做，因为室内过敏原。缺乏几丁质特异性检测是我们评估几丁质暴露对哮喘恶化和发展的影响程度的关键障碍。 这项研究的长期目标是了解空气中微生物暴露（及其成分，如几丁质）在哮喘发展和恶化中的作用。我们的目标是建立一种定量测定空气或灰尘中环境样品中几丁质的ELISA方法。我们将系统地研究目前可用的几丁质结合蛋白的特异性，选择 最佳的，并检查其特异性，用于在ELISA测定中的进一步开发。我们将制定一个协议，用于测试环境样品的处理和检测不溶性甲壳素的独特问题。最后，我们将使用新的甲壳素测定存档的灰尘样品从以前的队列研究，并将比较甲壳素含量与现有措施的含甲壳素的生物（可培养的真菌）和它们的过敏原，如Der p1和Der f1尘螨，Bla g1蟑螂，Alt a1链格孢菌。本研究的成功结果和良好表征的几丁质环境测定的产生将对该领域产生相当大的影响，使其能够在探索几丁质暴露对哮喘恶化和发展的影响程度以及任何基因-环境相互作用的程度方面取得进展。 公共卫生相关性：哮喘的患病率正在增加，并且与各种环境暴露密切相关。该项目将开发一种新的甲壳素环境分析方法，以便将来评估其在过敏性致敏和哮喘的发展和进展中的作用，如果显着，可能会导致新的公众 健康干预措施，以减少过敏性疾病。