Oral drug delivery is typically preferred as a therapeutic intervention due to the complexities and expenses associated with intravenous administration. However, some drugs are poorly absorbed orally, requiring intravenous administration to bypass the gastrointestinal tract and deliver the drug directly into the bloodstream. Thus, there is an urgent need to develop novel drug delivery platforms to overcome the challenges of oral drug delivery with low solubility, low permeability, oral degradation, and low bioavailability. Advances in extracellular vesicles (EVs) as natural carriers have provided emerging approaches to improve potential therapeutic applications. Milk not only contains traditional nutrients but is also rich in EVs. In this Review, we focus mainly on the purification of milk EVs (mEVs), their safety, and the advantages of mEV-based drug carriers in combatting intestinal infections. Additionally, we summarize several advantages of mEVs over conventional synthetic carriers, such as low immunogenicity, high biocompatibility, and the ability to transfer bioactive molecules between cells. Considering the unmet gaps of mEVs in clinical translation, it is essential to review the cargo loading into mEVs and future perspectives for their use as natural drug carriers for oral delivery. This overview of mEV-based drug carriers for oral delivery sheds light on alternative approaches to treat clinical infections associated with intestinal pathogens and the development of novel oral delivery systems.

中文翻译：

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牛奶细胞外囊泡：增强口服药物递送对抗细菌感染的天然纳米颗粒

由于静脉给药的复杂性和费用，口服药物递送通常优选作为治疗干预措施。然而，有些药物口服吸收较差，需要静脉注射绕过胃肠道，将药物直接输送到血液中。因此，迫切需要开发新型药物递送平台来克服口服药物递送的低溶解度、低渗透性、口服降解和低生物利用度的挑战。细胞外囊泡（EV）作为天然载体的进展为改善潜在的治疗应用提供了新兴方法。牛奶不仅含有传统营养素，还富含EV。在这篇综述中，我们主要关注牛奶 EV（mEV）的纯化、其安全性以及基于 mEV 的药物载体在对抗肠道感染方面的优势。此外，我们总结了 mEV 相对于传统合成载体的几个优点，例如低免疫原性、高生物相容性以及在细胞之间转移生物活性分子的能力。考虑到 mEV 在临床转化中尚未满足的差距，有必要回顾 mEV 中的货物装载以及它们作为口服递送的天然药物载体的未来前景。基于 mEV 的口服给药药物载体的概述揭示了治疗与肠道病原体相关的临床感染的替代方法以及新型口服给药系统的开发。