In addition to direct cell-to-cell contact, dendritic cells (DCs) can regulate the onset of adaptive immunity through the secretion of nano-sized membrane structures, called extracellular vesicles (EVs). This novel mode of communication between cells has added a new layer of complexity to the regulation of immune responses. DCs secrete into their environment different types of EVs containing immunomodulatory molecules that have distinct structural and biochemical properties depending on their intracellular site of origin. Exosomes are generated inside multivesicular bodies and are secreted when these compartments fuse with the plasma membrane, whereas microvesicles are formed and released by budding from the cells' plasma membrane. Once outside the cell of origin, these vesicles can reach target cells through membrane receptor-ligand interactions, modifying their physiological state by the transfer of the EV content or by triggering cell signaling at the cells' surface. Particularly, EVs released by DCs contain major histocompatibility complex (MHC) class I and class II molecules able to activate cognate T cells and promote humoral responses. These activities motivated the use of DC-derived EVs in the treatment of cancer, infectious diseases and autoimmune disorders. The therapeutic potential of these vesicles led to the use of EVs from tumor antigen-loaded DCs in cancer clinical trials, although with limited clinical effects. In this review we will focus on the different EVs released by DCs, their composition and biogenesis, together with their proposed functions as immune regulators.

中文翻译：

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树突状细胞胞外囊泡。

除了直接的细胞间接触之外，树突状细胞（DC）还可以通过分泌称为细胞外囊泡（EVs）的纳米尺寸膜结构来调节适应性免疫的发作。细胞之间这种新颖的通讯方式为免疫反应的调节增加了新的复杂性。DCs向其环境分泌不同类型的包含免疫调节分子的EV，这些EV具有不同的结构和生化特性，具体取决于其细胞内起源部位。外泌体在多囊泡体内产生，并在这些小室与质膜融合时被分泌出来，而微囊泡则是通过从细胞的质膜中萌芽而形成和释放的。一旦离开原点，这些囊泡可通过膜受体-配体相互作用到达靶细胞，通过EV含量的转移或触发细胞表面的细胞信号传导来改变其生理状态。特别是，由DC释放的EV包含主要的组织相容性复合体（MHC）I类和II类分子，它们能够激活同源T细胞并促进体液反应。这些活动激发了直流衍生电动车在癌症，传染病和自身免疫性疾病治疗中的应用。这些囊泡的治疗潜力导致在癌症临床试验中使用载有肿瘤抗原的DC的EV，尽管其临床效果有限。在这篇综述中，我们将重点关注DC释放的不同EV，它们的组成和生物发生，以及它们作为免疫调节剂的拟议功能。通过转移EV含量或触发细胞表面的细胞信号传导来改变其生理状态。特别是，由DC释放的EV包含主要的组织相容性复合体（MHC）I类和II类分子，它们能够激活相关的T细胞并促进体液反应。这些活动激发了直流衍生电动车在癌症，传染病和自身免疫性疾病治疗中的应用。这些囊泡的治疗潜力导致在癌症临床试验中使用载有肿瘤抗原的DC的EV，尽管其临床效果有限。在这篇综述中，我们将重点关注DC释放的不同EV，它们的组成和生物发生，以及它们作为免疫调节剂的拟议功能。通过转移EV含量或触发细胞表面的细胞信号传导来改变其生理状态。特别是，由DC释放的EV包含主要的组织相容性复合体（MHC）I类和II类分子，它们能够激活相关的T细胞并促进体液反应。这些活动激发了直流衍生电动车在癌症，传染病和自身免疫性疾病治疗中的应用。这些囊泡的治疗潜力导致在癌症临床试验中使用载有肿瘤抗原的DC的EV，尽管其临床效果有限。在这篇综述中，我们将重点关注DC释放的不同EV，它们的组成和生物发生，以及它们作为免疫调节剂的拟议功能。