Signature Peptide Approach to Biomonitor MDI Exposure

描述（由申请人提供）：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化学物质。尽管异氰酸酯的致敏性已经被承认了60多年，但这些化学物质仍然是世界范围内哮喘的主要原因。疾病预防工作主要侧重于减少接触，因为接触是发展致病性化学过敏的最公认的危险因素。然而，对于指导有效的工业卫生和识别暴露风险至关重要的暴露监测/监测方法有限。我们建议通过定量暴露产生的特定化学肽偶联物的量，开发一种特征肽方法，用于生物监测异氰酸酯暴露。我们预测在外周血中积累和循环的化学偶联物水平，尽管在绝对规模上很低，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。如果这些最初的假设通过目前提出的研究产生的实验数据得到证实，那么特征肽方法可能最终被用作异氰酸酯哮喘预防的有效方法。此外，该研究可以作为其他职业/环境暴露于反应性低分子量化学品的模型。本研究的方法包括使用选择的反应监测-质谱法的血清样品与重同位素标记的肽偶联到化学。该方法的灵敏度将进一步提高；采用新型抗mdi单克隆抗体对特征肽进行免疫亲和纯化后再进行分析。该项目的具体目标是-目标1。建立从人血清样品中纯化mdi肽的亲和层析，然后采用LC-MS/MS进行定量分析。目标2。定量测定不同MDI暴露水平的工人血清中MDI肽的含量。目标3。通过基于任务的暴露测量、尿液分析和职业史，确定特征mdi肽与个人暴露水平之间的关系。NORA部门和NIOSH r2输出/结果-本申请按以下相关性顺序处理以下NORA部门和共同部门；暴露评估，制造，建筑，免疫和皮肤疾病，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.