Cells can communicate through extracellular vesicle (EV) secretion and uptake. Exosomes are lipid bilayer-enclosed EVs of 30–150 nm in diameter, which can transfer RNA, functional proteins, lipids, and metabolites to recipient cells in vivo. Most cell types, including immune cells, can secrete and uptake exosomes. Biogenesis, secretion, and uptake of immune cell-derived exosomes are regulated by intracellular proteins and extracellular stimuli. Immune cell-derived exosomes can mediate crosstalk between innate and adaptive immunity and regulate cancer progression and metastasis. The dichotomous roles of immune cell-derived exosomes towards tumor cells can induce suppressive or active immune responses. Hence, immune cell-secreted exosomes may have applications in cancer diagnosis and immunotherapy and could potentially be developed for vaccination and chemotherapy drug transportation.

细胞可以通过细胞外小泡（EV）分泌和摄取进行交流。外来体是直径为30-150纳米，其可以转运RNA，功能性蛋白质，脂质，和代谢物至受体细胞的脂质双层封闭电动车体内。大多数细胞类型，包括免疫细胞，都可以分泌和摄取外来体。免疫细胞衍生的外泌体的生物发生，分泌和摄取受细胞内蛋白质和细胞外刺激的调节。免疫细胞来源的外来体可以介导先天免疫和适应性免疫之间的串扰，并调节癌症的进展和转移。免疫细胞衍生的外来体对肿瘤细胞的二分作用可以诱导抑制性或主动性免疫反应。因此，分泌免疫细胞的外泌体可能在癌症诊断和免疫疗法中有应用，并有可能被开发用于疫苗接种和化学药物运输。