Pachane Bianca C, Carlson Bess, Queen Suzanne E, Selistre-de-Araujo Heloisa S, Witwer Kenneth W
Department of Molecular and Comparative Pathobiology Johns Hopkins University School of Medicine Baltimore Maryland USA.
Biochemistry and Molecular Biology Laboratory, Department of Physiological Sciences Universidade Federal de São Carlos - UFSCar São Carlos São Paulo Brazil.
J Extracell Biol. 2025 Apr 25;4(4):e70042. doi: 10.1002/jex2.70042. eCollection 2025 Apr.
The ‛stickiness' of extracellular vesicles (EVs) can pose challenges for EV processing and storage, but adhesive properties may also be exploited to immobilise EVs directly on surfaces for various measurement techniques, including super-resolution microscopy (SRM). Direct adhesion to surfaces may allow the examination of broader populations of EVs than molecular affinity approaches, which can also involve specialised, expensive affinity reagents. Here, we report on the interaction of EVs with borosilicate glass and quartz coverslips and on the effects of pre-coating coverslips with poly-L-lysine (PLL), a reagent commonly used to facilitate interactions between negatively charged surfaces of cells and amorphous surfaces. Additionally, we compared two mounting media conditions for SRM imaging and used immobilised EVs for a B-cell interaction test. Our findings suggest that borosilicate glass coverslips immobilise EVs better than quartz glass coverslips. We also found that PLL is not strictly required for EV retention but contributes to the uniform distribution of EVs on borosilicate glass coverslips. Overall, these findings suggest that standard lab materials like borosilicate glass coverslips, with or without PLL, can be effectively used for the immobilisation of EVs in specific imaging techniques.
细胞外囊泡（EVs）的“粘性”可能给EVs的处理和储存带来挑战，但也可以利用其粘附特性将EVs直接固定在表面，用于包括超分辨率显微镜（SRM）在内的各种测量技术。与分子亲和方法相比，直接粘附到表面可能允许检查更广泛的EVs群体，分子亲和方法还可能涉及特殊、昂贵的亲和试剂。在这里，我们报告了EVs与硼硅酸盐玻璃和石英盖玻片的相互作用，以及用聚-L-赖氨酸（PLL）预涂盖玻片的效果，PLL是一种常用于促进细胞带负电荷表面与无定形表面之间相互作用的试剂。此外，我们比较了用于SRM成像的两种封固介质条件，并将固定化的EVs用于B细胞相互作用测试。我们的研究结果表明，硼硅酸盐玻璃盖玻片比石英玻璃盖玻片能更好地固定EVs。我们还发现，EVs保留并不严格需要PLL，但PLL有助于EVs在硼硅酸盐玻璃盖玻片上均匀分布。总体而言，这些发现表明，像硼硅酸盐玻璃盖玻片这样的标准实验室材料，无论有无PLL，都可以有效地用于在特定成像技术中固定EVs。
