病原体与宿主的信息交流及机制是感染免疫的关键科学问题。外泌泡（exosome）是一种具有细胞间信号传递功能的细胞结构。申请者在血吸虫成虫培养上清中发现exosome样结构，并初步证实其有调节巨噬细胞极化的作用，提示：分泌exosome可能是血吸虫调控宿主免疫应答的一种重要方式，但目前对其作用及其机制缺乏系统研究。为此，拟采用已建立的技术体系，分离纯化日本血吸虫不同发育阶段（尾蚴、成虫和虫卵）分泌的exosome，利用电子显微镜、流式细胞术等技术开展生物学特征的比较研究；通过体内外实验，比较不同阶段虫体exosome对小鼠免疫应答及免疫细胞的作用；采用质谱和二代测序技术，比较不同阶段虫体exosome的组分差异，并对exosome中重要组分的免疫学活性进行研究。本项目的开展，将揭示日本血吸虫exosome对终宿主免疫应答的调节作用及其分子途径，进一步阐明血吸虫与宿主相互作用的精细机制。

It is a core scientific problem that communtions between pathogens and host . The Exosome are small cellular particles which play their roles in promoting cell-to-cell communications and modulating physiological functions of cells. Though some studies have showed that exosomes may be the key mechanisms related to the immune evasion, the mechanisms is still unclear. Thus, we have established the isolation and identification technology of exosomes and succuessfully got the exosomes from secretions of adult of Schistosoma japonicum. In this study, we aim to isoloate the exosomes from cercariae, schistosomula, adults and eggs of Schistosoma japonicum by the high-speed gradient centrifugation method, determine the size and surface characteristics of exosomes from different stages of S.japonicum, identify the contents of exosomes by mass spectrometry and DNA sequencing, observe the functions of exosomes and the main compound of exosomes related to the immune response of BALB/c and immune cell functions in vivo and in vitro, and confirm the exact role of the exosomes during infection of S.japonicum. This research will contribute to understanding the biological function ot the main components of exosomes isolated from the S.japonicum and further revealing the precise molecular mechanisms of immune evasion.