Extracellular vesicles (EVs) are diverse nanoparticles with large heterogeneity in size and molecular composition. Although this heterogeneity provides high diagnostic value for liquid biopsy and confers many exploitable functions for therapeutic applications in cancer detection, wound healing and neurodegenerative and cardiovascular diseases, it has also impeded their clinical translation—hence heterogeneity acts as a double-edged sword. Here we review the impact of subpopulation heterogeneity on EV function and identify key cornerstones for addressing heterogeneity in the context of modern analytical platforms with single-particle resolution. We outline concrete steps towards the identification of key active biomolecules that determine EV mechanisms of action across different EV subtypes. We describe how such knowledge could accelerate EV-based therapies and engineering approaches for mimetic artificial nanovesicle formulations. This approach blunts one edge of the sword, leaving only a single razor-sharp edge on which EV heterogeneity can be exploited for therapeutic applications across many diseases.

细胞外囊泡 （EV） 是多种多样的纳米颗粒，在大小和分子组成上具有很大的异质性。尽管这种异质性为液体活检提供了很高的诊断价值，并赋予了癌症检测、伤口愈合、神经退行性和心血管疾病等治疗应用的许多可开发功能，但它也阻碍了它们的临床转化——因此异质性是一把双刃剑。在这里，我们回顾了亚群异质性对 EV 功能的影响，并确定了在具有单粒子分辨率的现代分析平台背景下解决异质性的关键基石。我们概述了鉴定关键活性生物分子的具体步骤，这些生物分子决定了不同 EV 亚型的 EV 作用机制。我们描述了这些知识如何加速基于 EV 的疗法和模拟人工纳米囊泡制剂的工程方法。这种方法钝化了剑的一把锋，只留下一个锋利的锋利边缘，EV 异质性可用于许多疾病的治疗应用。