Li Xiaobo, Zhang Zhiren, Beiter Thomas, Schluesener Hermann J
Institute of Brain Research, D-72076 Tuebingen, Germany.
Arch Immunol Ther Exp (Warsz). 2005 Jul-Aug;53(4):329-35.
Exosomes are small membrane vesicles derived from late endosome. They are about 30--100 nm in diameter. The secretion of exosomes is a process in which multivesicular bodies fuse with the cell membrane, and all cells that contain multivesicular endocytic compartments could theoretically secrete exosomes. The surprising biological functions of exosomes are only slowly being unveiled, but it is already clear that they serve to remove obsolete membrane proteins and act as messages of inter-cellular communication. Exosomes derived from tumor or antigen-presenting cells have been extensively investigated. They are released into the extracellular environment and fuse with the membranes of neighboring cells, delivering membrane and cytoplasmic proteins from one cell to another. Exosomes carry immunorelevant structures which play important roles in immune response, such as MHC molecules, costimulatory molecules, heat shock proteins, and naive tumor antigens. Therefore they have been suggested as potential vaccines. Consequently, exosomes have shown considerable anti-tumor effect in several studies and are in phase I clinical trials.
外泌体是源自晚期内体的小膜泡。它们的直径约为30-100纳米。外泌体的分泌是多泡体与细胞膜融合的过程，理论上所有含有多泡内吞小室的细胞都能分泌外泌体。外泌体令人惊讶的生物学功能只是逐渐被揭示出来，但已经清楚的是，它们有助于清除过时的膜蛋白，并充当细胞间通讯的信息载体。源自肿瘤或抗原呈递细胞的外泌体已得到广泛研究。它们被释放到细胞外环境中，并与相邻细胞的膜融合，将膜蛋白和细胞质蛋白从一个细胞传递到另一个细胞。外泌体携带在免疫反应中起重要作用的免疫相关结构，如MHC分子、共刺激分子、热休克蛋白和幼稚肿瘤抗原。因此，它们被认为是潜在的疫苗。因此，外泌体在多项研究中显示出显著的抗肿瘤作用，目前正处于I期临床试验阶段。
