Department of Optometry, Chung Shan Medical University, Taichung, Taiwan; Institute of Optometry, Chung Shan Medical University, Taichung, Taiwan; Department of Ophthalmology, Chung Shan Medical University Hospital, Taichung, Taiwan.
School of Traditional Chinese Medicine, Chang Gung University College of Medicine, Taoyuan, Taiwan.
Clin Chim Acta. 2019 Jun;493:14-19. doi: 10.1016/j.cca.2019.02.021. Epub 2019 Feb 21.
Exosomes, also called extracellular vesicles (EVs), are membranous structures measuring between 40 and 100 nm. Exosomes, secreted by various cells of the human body into body fluids, contain protein, mRNA, miRNA, and signaling molecules. Physiologically, exosomes assist in the intercellular transport of protein and RNA. Immunologically, exosomes exhibit antigen-presenting capability. In recent studies, exosomes were found to be associated with the pathophysiology of cardiovascular, renal, neurological, and ocular diseases. In addition, exosomes may play a major role in cancer metastasis. Due to the extremely small size and scarcity of exosomes in living samples, many early studies utilized sucrose density gradient ultracentrifugation for exosome collection. However, sucrose density gradient ultracentrifugation is rather time consuming and requires large biological sample quantities. Newer exosome studies combined immunoaffinity and microfluidic system approaches for more efficient exosome collection. Our review summarizes existing methods for EV isolation and notes their advantages and disadvantages. These promising approaches are all characterized by isolation efficiency, and savings in cost, labor, and time. Optimization of current methods is a necessary step toward clinically-relevant diagnostic product production, but the fact that EVs are already widely used in disease diagnosis and treatment encourages continued efforts.
外泌体，也称为细胞外囊泡（EVs），是一种膜性结构，直径在 40 到 100nm 之间。外泌体由人体各种细胞分泌到体液中，包含蛋白质、mRNA、miRNA 和信号分子。从生理上讲，外泌体有助于蛋白质和 RNA 的细胞间转运。从免疫学角度看，外泌体具有抗原呈递能力。在最近的研究中，发现外泌体与心血管、肾脏、神经和眼部疾病的病理生理学有关。此外，外泌体可能在癌症转移中起主要作用。由于活样本中外泌体的尺寸极小且数量稀少，许多早期研究利用蔗糖密度梯度超速离心法来收集外泌体。然而，蔗糖密度梯度超速离心法耗时较长，且需要大量的生物样本。新的外泌体研究结合免疫亲和和微流控系统方法，以提高外泌体的收集效率。我们的综述总结了现有的 EV 分离方法，并指出了它们的优缺点。这些有前途的方法都具有分离效率高、成本、劳动力和时间节省的特点。优化现有方法是向临床相关诊断产品生产迈出的必要一步，但 EV 已经广泛应用于疾病诊断和治疗这一事实鼓励人们继续努力。
