过敏疾病是21世纪重点防治的三大疾病之一，它已对医疗资源造成极大的负担。某些过敏原蛋白在体内环境中可发生酪氨酸硝基化反应，从而其致敏性得到增强。受限于实验技术等问题，难以直接对进入人体的过敏原进行实时分析，因此体内硝基化反应的动力学特征等科学问题尚未被解决，进而阻碍正确地理解过敏原蛋白在免疫应答中的动态作用。本项目拟研发液滴微流控芯片与纳升电喷雾电离质谱分析联用系统，模拟体内heme-NaNO2-H2O2体系过敏原蛋白硝基化反应，分析其反应动力学。选择20种左右具有不同特征氨基酸序列的蛋白分子，研究不同条件下的硝基化程度及变化规律。结合蛋白质共价修饰的生物信息学分析、免疫亲和毛细管电泳、全序列覆盖度蛋白质组学等技术，进一步探明常见的过敏原蛋白的硝基化位点，阐明硝基化修饰与免疫原性的关系，并构建包含8至10种中国人群常接触到过敏原蛋白硝基化修饰信息分子库。

Allergic disease is one of the three global epidemics of the 21st century and has placed a heavy burden on medical care providers. The nitration of proteins’ tyrosine residues to 3-nitro-tyrosine can occur in the physiological environment and subsequently enhancing their allergenicities. Limited to experimental methods, it is difficult to directly investigate the nitration reaction within human body in a real-time manner. Hence, the kinetics of nitration reaction and relative scientific questions have not yet been answered, thus impeding the understanding on the dynamic role of allergen proteins in human immune response. This project aims to develop microfluidic chip coupled with electrospray ionization mass spectrometry to simulate the nitration reaction of allergen proteins in the presence of heme-NaNO2-H2O2 in human body. The research plan is to select ~20 protein molecules to investigate the nitration degree under varying conditions. Together with bioinformatics analysis, immunoaffinity capillary electrophoresis and other technologies, we will further discover common amino acids that can occur nitration reaction and clarify the relationship between protein’s nitration modification and immunogenicity. Also, we expect that a library composed of information about the nitration modification of 8-10 common allergen proteins on Chinese diet.