Eosinophils facilitate bacterial clearance by mediating antibacterial T cell responses in the respiratory tract

项目3：项目摘要/摘要 呼吸系统疾病是全世界发病率和死亡率的主要原因之一。尽管如此，疫苗 CDC确认百日咳是一种新出现的传染病，可导致数百人死亡 发达国家和欠发达国家每年都有数以千计的婴儿和儿童。不幸的是， 未能控制百日咳并不是一个孤立的现象，就像类似的缺乏保护措施一样 其他呼吸道病原体，如肺炎球菌。大多数针对呼吸道的疫苗策略都是通用的 细菌性疾病关注的是抗体反应的产生，它忽略了T细胞和 粘膜免疫在产生持久保护反应中的作用。嗜酸性粒细胞是已知的一种免疫细胞 在预防寄生蠕虫(蠕虫)感染方面发挥关键作用，表明在 对病原体的整体免疫反应。最近的研究表明，嗜酸性粒细胞在适应中起着重要作用。 协调胃粘膜T和B细胞反应的细胞免疫反应及其维持 粘膜动态平衡。本项目将利用感染支气管败血波氏杆菌的小鼠，一种易治的 百日咳小动物模型研究嗜酸性粒细胞作为T细胞反应驱动力的作用 呼吸道细菌感染。我们的初步数据表明，嗜酸性粒细胞需要清除 支气管败血波尔德氏菌来自小鼠呼吸道。此外，缺乏嗜酸性粒细胞的小鼠表现出 持续感染，不能分泌促炎细胞因子，不能产生有效的抗体 反应，表明嗜酸性粒细胞促进获得性免疫。建议的研究完成后， 提高我们对嗜酸性粒细胞生物学和嗜酸性粒细胞用于驱动T细胞反应的机制的理解。 我们预计，从我们的工作中获得的知识将为改进的发展确定新的目标 预防百日咳和可能由呼吸道病原体引起的其他疾病的疫苗。

PROJECT 3: PROJECT SUMMARY/ABSTRACT Respiratory diseases are among the major causes of morbidity and mortality worldwide. Despite that vaccines are available, the CDC recognizes Whooping cough as a reemerging infectious disease that kills hundreds of thousands of babies and children each year, both in developed and underdeveloped countries. Unfortunately, the failure to control Whooping cough is not an isolated phenomenon, as a similar lack of protection is seen with other respiratory pathogens, such as pneumococcus. Common to most vaccines strategies against respiratory bacterial diseases is a focus on the generation of antibody responses, which overlooks roles for T cells and mucosal immunity in producing durable protective responses. Eosinophils are a type of immune cell that is known to play pivotal roles in protection against infection by parasitic helminths (worms), indicating a function in the overall immune response to pathogens. Recent studies reveal that eosinophils play important roles in adaptive cellular immune responses by coordinating T and B cell responses in the gastric mucosa, and in maintenance of mucosal homeostasis. This project will make use of Bordetella bronchiseptica infection of mice, a tractable small animal model for Whooping cough, to investigate the role of eosinophils as drivers of the T cell responses in respiratory bacterial infections. Our preliminary data indicate that eosinophils are required for clearance of Bordetella bronchiseptica from the mouse respiratory tract. Moreover, mice lacking eosinophils present with a persistent infection, fail to secrete pro-inflammatory cytokines, and are unable to generate effective antibody responses, suggesting that eosinophils promote adaptive immunity. Completion of the proposed studies will improve our understanding of eosinophil biology and the mechanisms eosinophils use to drive T cell responses. We anticipate that the knowledge gained from our work will identify novel targets for the development of improved vaccines against Whooping cough and possibly other diseases caused by respiratory pathogens.