Underlying mechanisms of schistosome/snail compatibility

描述（由申请人提供）：本提案的目的包括 各种生物化学和分子方法来确定 抗性（R）与敏感（S）B之间的菌株特异性差异。 这将导致更好地了解国防活动， 蜗牛PI假设：（a）可能存在菌株特异性差异 在血细胞的呼吸爆发中;（B）存在敏感性差异 在S和R血细胞中， 呼吸爆发（例如氯化胺）;（c）可能存在应变 特异性基因转录物诱导的差异。 这项提案的大部分工作集中在体外分析的使用上 系统确定孢子囊杀死，和PI已经开发出的方法， 选择性抑制O2和N依赖途径中的某些酶。 自上次更新以来，PI列出了11篇手稿（已发表和发表）。 新闻/提交）和8篇评论文章，涉及这一问题的各个方面。 蜗牛/吸虫关系。其他几篇没有直接关系的论文是 列出了作为证明PI技术专业知识的支持 为将来的研究。上一个供资期间的调查结果导致 至少在体外，O2依赖性和非依赖性 机制可能在杀死孢子囊中起作用。这是在CMC 试验得到了实质性的改进，发现H2 O2参与了杀伤作用， （尽管他们未能显示R和S中ROS产生的差异， 非CMC测定中的血细胞）。这些实验得出了一个前提， 在抗性蜗牛中孢子囊的破坏可能是由于一种缺陷的 髓过氧化物酶（MPO），允许H2 O2介导杀伤，而MO血细胞 在H2 O2能够充分发挥其作用之前将其解毒。 PI还开发了大量证据表明NO和H2 O2起作用 协同作用杀死孢子囊。这些结果将作为基础， 进一步探索这两种途径杀死孢子囊。

DESCRIPTION (provided by the applicant): The aims of this proposal cover a variety of biochemical and molecular approaches to determine the strain-specific differences between resistant (R) vs. susceptible (S) B. glabratathat would lead to a greater understanding of defense activity in the snail. The PI hypothesizes that: (a) there can be strain-specific differences in the respiratory burst of hemocytes; (b) that sensitivity differences exist in the S and R hemocytes to negative influence of a normal intermediate of the respiratory burst (e.g. chlorinated amines) and; (c) there may be strain differences in induction of specific gene transcripts. Much of the work in this proposal centers on the use of an in vitro assay system for determining sporocyst killing, and the PI has developed ways for selectively inhibiting certain enzymes in O2 and N dependent pathways. Since the last renewal the PI lists 11 manuscripts (published and in press/submitted) and 8 review articles dealing with various aspects of this snail/trematode relationship. Several other papers not directly related are listed that serve as support for demonstrating the PI's expertise in techniques for future studies. Findings during the last funding period led to the understanding that, at least in vitro, both O2 - dependent and -independent mechanisms may play a role in sporocyst killing. This came about after the CMC assay was substantially improved, and finding that H2O2 was involved in killing (although they failed to show differences in ROS production in R and S hemocytes in non-CMC assays). These experiments led to the premise that destruction of sporocysts in resistant snails may be due to a defective myeloperoxidase (MPO) that allows H2O2 to mediate killing, whereas MO hemocytes detoxify H2O2 before it is able to exert its effect fully. The PI also has developed substantial evidence that NO and H2O2 play synergistic roles in sporocyst killing. These results will serve as a basis to explore further these two pathways in sporocyst killing.