ABSTRACT

Extracellular vesicles (EVs) present in blood originate from cells of different origins such as red blood cells (RBCs), platelets and leukocytes. In patients with cancer, a small portion of EVs originate from tumour cells and their load is associated with poor clinical outcome. Identification of these tumour-derived extracellular vesicles (tdEVs) is difficult as they are outnumbered by EVs of different tissue of origin as well a large number of lipoproteins (LPs) that are in the same size range. In order to detect tdEVs from the abundant presence of other particles, single-particle techniques are necessary. Here, synchronous Rayleigh and Raman scattering is used for that purpose. This combination of light scattering techniques identifies optically trapped single particles based on Rayleigh scattering and distinguishes differences in chemical composition of particle populations based on Raman scattering. Here, we show that tdEVs can be distinguished from RBC EVs and LPs in a label-free manner and directly in suspension.

摘要

血液中存在的细胞外囊泡（EVs）来自不同来源的细胞，例如红细胞（RBC），血小板和白细胞。在患有癌症的患者中，一小部分电动汽车源自肿瘤细胞，其负荷与不良的临床预后相关。这些肿瘤来源的细胞外囊泡（tdEVs）的鉴定非常困难，因为它们被不同来源组织的EVs和相同大小范围内的大量脂蛋白（LP）所取代。为了从大量其他颗粒中检测出tdEV，单颗粒技术是必要的。在此，同步瑞利和拉曼散射用于该目的。光散射技术的这种组合基于瑞利散射来识别被光学捕获的单个粒子，并基于拉曼散射来区分粒子群体的化学组成差异。在这里，我们证明了tdEVs可以与RBC EVs和LPs以无标签的方式直接区别开来。