中文摘要：

外泌体是由细胞分泌的直径在30~100 nm之间的微小囊泡状结构,内含来源于细胞相关的蛋白质与核苷酸等生物分子。外泌体可由几乎所有类型的细胞分泌,并且在组织细胞生理和病理情况下皆可持续分泌,存在于多种体液当中。目前,外泌体作为细胞间通讯的新途径和作为疾病诊断的生物标记方面取得瞩目的研究进展。本文从外泌体的组成特征及其生物学作用进行了综述,重点介绍了外泌体作为细胞通讯的新途径和内含的蛋白质和核苷酸作为一种新型的生物标记物在疾病诊断和临床方面的应用潜力,还对外泌体在生命科学研究领域的潜在作用及其存在的问题进行了展望。

英文摘要：

Exosomes are small extracellular vesicles（ 30 ~ 100 nm diameter） derived from the endosomal system in almost all kind of cells under physiological and pathological condition. It has shown that exosomes mediated cell-to-cell communication to modulate a variety of biological processes. Exosome can be secreted by several cell types and retrieved from body fluids,such as blood,urine,saliva and cerebrospinal fluid. In addition to proteins and lipids,it also contains nucleic acids,like mRNAs and miRNAs with normal expression or targeting activities. These features have prompted extensive research to exploit exosomes as a source of biomarkers for cancer and neurodegenerative disorders. We reviewed the characteristics, component and function of the exosome according to the included proteins and nucleotides. The immunomodulatory and regenerative properties of exosome inspires the application for therapeutic purposes. Nevertheless,questions on exosome biogenesis and secretion mechanism,and physiological or pathological function remained to be fully addressed.