Signature Peptide Approach to Biomonitor MDI Exposure

描述(由申请者提供)：这项资助申请的重点是开发一种新的方法来预防由异氰酸酯引起的职业性哮喘，异氰酸酯是制造聚氨酯的基本交联剂。尽管60多年来人们认识到异氰酸酯的过敏性，但这些化学物质仍然是全球哮喘的主要原因。疾病预防工作主要侧重于减少接触，因为接触是最公认的致病化学物质过敏发展的风险因素。然而，对于指导有效的工业卫生和确定暴露风险至关重要的暴露监测/监测方法是有限的。我们建议，可以开发一种标志性多肽方法来对异氰酸酯暴露进行生物监测，方法是定量测定暴露产生的特定化学-多肽结合物的数量。我们预测在外周血液中累积和循环的化学结合物水平，尽管绝对值很低，但与接受的内部剂量成比例，因此，代表了暴露监测的有效生物标志物。如果这些初始假设通过目前提议的研究产生的实验数据得到证实，标志性多肽方法最终可能被用作预防异氰酸酯哮喘的有效方法。此外，这项研究还可以作为其他职业/环境暴露于活性低分子化学品的模式。本研究的方法包括使用选择性反应监测-质谱法，在血清样本中添加与化学物质结合的重同位素标记肽。该方法的灵敏度将进一步提高；通过使用新型抗MDI单抗进行免疫亲和，在分析之前对标志肽进行纯化。本项目的具体目的是：1.建立用亲和层析和LC-MS/MS联用从人血清样品中纯化的MDI多肽的定量检测方法。目的2.定量不同水平接触MDI工人血清中标志性MDI多肽的量。目的3.根据基于任务的暴露测量、尿液分析和职业史，确定标志性MDI多肽与个人暴露水平之间的关联。NORA部门和NIOSH R2P产出/成果--本申请按以下相关顺序涉及以下NORA部门和协力因素：暴露评估、制造、建筑、免疫和皮肤病以及呼吸系统疾病。

DESCRIPTION (provided by applicant): This grant application focuses on developing a new approach for preventing occupational asthma caused by isocyanates, the essential cross-linking chemical for making polyurethane. Despite recognition of isocyanate's allergenicity for over 60 years, these chemicals remain a leading cause of asthma world-wide. Disease prevention efforts focus primarily on exposure reduction, as exposure is the best-recognized risk factor for development of pathogenic chemical hypersensitivity. However, methods of exposure surveillance / monitoring, essential to guiding effective industrial hygiene and identification of exposure risks, are limited. We propose that a signature peptide method can be developed for bio-monitoring isocyanate exposure, by quantitating the amount of a specific chemical-peptide conjugate that results from exposure. We predict the level of chemical conjugate that accumulates and circulates in the peripheral blood, albeit low on an absolute scale, are proportion to the internal does received and thus, represent an effective biomarker for exposure surveillance. If these initial hypotheses are proven through the experimental data generated through the presently proposed studies, the signature peptide methodology may ultimately be employed as an effective approach to isocyanate asthma prevention. Furthermore, the study may serve as a model for other occupational / environmental exposures to reactive low-molecular weight chemicals. The approach of the present study involves using selected reaction monitoring-mass spectrometry of serum samples spiked with a heavy isotope labeled peptide conjugated to chemical. The sensitivity of the approach will be increased further; by using novel anti-MDI monoclonal antibodies to immunoaffinity purify the signature peptide before analysis. The specific aims of the project are- Aim 1. Develop quantitative assay for measuring MDI-peptide purified from human serum samples by affinity chromatography, followed by LC-MS/MS. Aim 2. Quantitate the amount of signature MDI-peptide present in serum of workers with varying levels of MDI exposure. Aim 3. Determine the association between signature MDI-peptide and personal exposure levels, estimated from task-based exposure measurements, urine analysis and occupational history. NORA Sectors & NIOSH r2p Output/Outcomes- The present application addresses the following NORA sectors and cosectors, in the following order of relevance; Exposure Assessment, Manufacturing, Construction, Immune and Dermal Diseases, and Respiratory Diseases.