外来体被认为是一种脂质双层结构包裹而成的囊性液泡,直接跨度在30~100 nm之间,可广泛来源于哺乳动物各类细胞类型,包括淋巴细胞、上皮细胞、内皮细胞和肿瘤细胞等。在真核细胞完整生命周期中,胞内各种囊性结构形成早期内涵体,而以腔内小泡形成为主要形态标志的晚期内涵体形成后,继续吸收胞内各种细胞成分及胞膜碎片,积聚于细胞核周边,通过三磷酸鸟苷酶活化蛋白(guanosinetriphos- Exosomes are considered to be cystic vacuoles surrounded by a lipid bilayer structure with a direct span of 30-100 nm and can be derived from a wide range of mammalian cell types including lymphocytes, epithelial cells, endothelial cells And tumor cells. In the complete life cycle of eukaryotic cells, various cytoplasmic cytoplasm formation of early endosomes, and the formation of intracavitary vesicles as the main morphological signs of late endosome formation, continue to absorb a variety of intracellular cellular components and membrane Debris, accumulated in the peri-nucleus, through the guanosine triphosphate enzyme activating protein (guanosinetriphos-