As extracellular vesicles secreted by cells, exosomes are intercellular signalosomes for cell communication and pharmacological effectors. Because of their special properties, including low toxicity and immunogenicity, biodegradability, ability to encapsulate endogenous biologically active molecules and cross the blood-brain barrier (BBB), exosomes have great therapeutic potential in cerebrovascular and neurodegenerative diseases. However, the poor targeting ability of natural exosomes greatly reduces the therapeutic effect. Using engineering technology, exosomes can obtain active targeting ability to accumulate in specific cell types and tissues by attaching targeting units to the membrane surface or loading them into cavities. In this review, we outline the improved targeting functions of bioengineered exosomes, tracing and imaging techniques, administration methods, internalization in the BBB, and therapeutic effects of exosomes in cerebrovascular and neurodegenerative diseases and further evaluate the clinical opportunities and challenges in this research field.

中文翻译：

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工程外泌体：脑血管和神经退行性疾病治疗所需的目标跟踪特性。

作为细胞分泌的细胞外囊泡，外泌体是细胞间信号体，用于细胞通讯和药理效应。由于其特殊的性质，包括低毒性、免疫原性、生物可降解性、封装内源性生物活性分子和穿过血脑屏障（BBB）的能力，外泌体在脑血管和神经退行性疾病方面具有巨大的治疗潜力。然而，天然外泌体较差的靶向能力大大降低了治疗效果。利用工程技术，外泌体可以通过将靶向单元附着在膜表面或将其装载到空腔中，获得主动靶向能力，在特定细胞类型和组织中积累。在这篇综述中，我们概述了生物工程外泌体改进的靶向功能、示踪和成像技术、给药方法、血脑屏障内化以及外泌体在脑血管和神经退行性疾病中的治疗效果，并进一步评估了该研究领域的临床机会和挑战。