应用同步辐射技术研究雾霾中颗粒物诱发过敏的机制

Haze has become a critical environmental problem that seriously affects the health of the residents in our country. It can trigger a variety of allergic diseases, but the study on the mechanism of allergy induced by haze particles is seriously lacking in our country. By combining synchrotron radiation techniques and cell molecular biology, this project intends to study the key scientific problems of the relationship between the chemical composition of particles from different sources with different particle sizes, the valence state and distribution of elements in the particles and the structure of the particles in haze and the mechanism of induced allergy. In situ detection technology of single particle, single cell, single particle and single cell interface is to be established with the advantages of in situ high sensitivity, high resolution and element specificity of synchrotron radiation technology. Combined with the methods of cell molecular biology and animal toxicology, the stimulating effect of different particle sizes on mast cells from the two important sources of haze (coal combustion industry emission and automobile exhaust) in Beijing, Tianjin, Hebei region is to be studied. The relationship between the composition, state, structure and surface properties of particles from different sources, with different particle size and the mechanism of induced allergy, as well as the difference in the degree of allergy induced by biogenetic and abiotic proto are to be revealed. This will serve as a scientific basis for reducing allergy risk and allergy prevention during haze period.

雾霾已成为严重影响我国居民身体健康的重大环境问题，其能促发多种过敏疾病，但是我国对雾霾颗粒物诱发过敏机制的研究却严重缺乏。本项目拟以同步辐射技术与细胞分子生物学方法相结合，对雾霾中不同来源、不同粒径范围颗粒物化学组成、元素种态与分布、结构等物化性质与其诱发过敏反应机制的关系这个关键科学问题进行研究，利用同步辐射技术的原位、高灵敏度、高分辨率、元素特异性的优点，建立单颗粒、单细胞、单颗粒与单细胞接触界面的原位检测技术，结合细胞分子生物学和动物毒理学实验方法，研究京津冀城区雾霾的两个重要来源（燃煤工业排放和汽车尾气）中不同粒径颗粒物对肥大细胞的激发效应。揭示不同来源、不同粒径颗粒物元素组成、种态、结构及表面性质与其诱发过敏反应机制的关系，以及生物原与非生物原它们之间诱发过敏反应程度的差异性。以期为雾霾期间降低人们过敏风险及过敏防治提供科学依据。

雾霾已成为严重影响我国居民身体健康的重大环境问题，其能促发多种过敏疾病，但是我国对雾霾颗粒物诱发过敏机制的研究却严重缺乏。本研究立足于深受雾霾危害的京津冀地区，利用同步辐射及分子生物学实验技术，科学评价不同来源、不同组分雾霾颗粒物诱发过敏的效应与机制，为雾霾期间降低人们过敏风险及过敏防治提供科学依据，为保护人民身体健康做出贡献。主要研究内容及结果包括：1.为评价不同来源雾霾颗粒物的致敏（增敏）效应，我们采集了两个主要污染源的颗粒物（燃煤源及柴油车尾气源），利用同步辐射技术和理化分析方法对采集到的颗粒物的理化性质进行表征，并对颗粒物中非生物原成分的致敏效应进行体外实验，结果表明上述颗粒物均未显示出显著的致敏或增敏效应。2.为评价不同组分雾霾颗粒物的致敏（增敏）效应，我们根据前期对雾霾颗粒物的表征结果，选取其中12种典型水溶性成分，以及6种非水溶性成分进行肥大细胞激活实验，以筛选雾霾颗粒物中的关键致敏（增敏）组分。结果表明，20 nm SiO2是雾霾颗粒物中的关键增敏组分，其可通过IgE途径，发挥协同增敏作用。3.为了揭示SiO2的协同增敏机制，我们应用TEM、同步辐射STXM、Western blot等技术对SiO2与肥大细胞的作用方式及相关信号通路展开研究，并采用动物实验，从整体水平层面揭示SiO2加重过敏性疾病的潜在机制。体外实验证实20 nm SiO2可进入肥大细胞内部促进细胞脱颗粒，其分子机制，可能是通过增加ERK1/2磷酸化水平，激活MAPK通路，进而增强IgE介导的致敏肥大细胞活化；体内实验表明，20 nm SiO2颗粒暴露能提高OVA致敏小鼠IL-4和IL-6的分泌，募集肥大细胞到肺组织炎症部位，增强肥大细胞活化和组胺分泌，进而加重过敏性气道反应。