Sangha Gurneet S, Weber Callie M, Sapp Ryan M, Setua Saini, Thangaraju Kiruphagaran, Pettebone Morgan, Rogers Stephen C, Doctor Allan, Buehler Paul W, Clyne Alisa M
Fischell Department of Bioengineering, University of Maryland, College Park, MD, United States.
Department of Pediatrics, Center for Blood Oxygen Transport and Hemostasis, University of Maryland School of Medicine, Baltimore, MD, United States.
Front Physiol. 2023 Aug 30;14:1246910. doi: 10.3389/fphys.2023.1246910. eCollection 2023.
Generating physiologically relevant red blood cell extracellular vesicles (RBC-EVs) for mechanistic studies is challenging. Herein, we investigated how to generate and isolate high concentrations of RBC-EVs via shear stress and mechanosensitive piezo1 ion channel stimulation. RBC-EVs were generated by applying shear stress or the piezo1-agonist yoda1 to RBCs. We then investigated how piezo1 RBC-EV generation parameters (hematocrit, treatment time, treatment dose), isolation methods (membrane-based affinity, ultrafiltration, ultracentrifugation with and without size exclusion chromatography), and storage conditions impacted RBC-EV yield and purity. Lastly, we used pressure myography to determine how RBC-EVs isolated using different methods affected mouse carotid artery vasodilation. Our results showed that treating RBCs at 6% hematocrit with 10 µM yoda1 for 30 min and isolating RBC-EVs via ultracentrifugation minimized hemolysis, maximized yield and purity, and produced the most consistent RBC-EV preparations. Co-isolated contaminants in impure samples, but not piezo1 RBC-EVs, induced mouse carotid artery vasodilation. This work shows that RBC-EVs can be generated through piezo1 stimulation and may be generated under physiologic flow conditions. Our studies further emphasize the importance of characterizing EV generation and isolation parameters before using EVs for mechanistic analysis since RBC-EV purity can impact functional outcomes.
生成用于机制研究的生理相关红细胞细胞外囊泡(RBC-EVs)具有挑战性。在此,我们研究了如何通过剪切应力和机械敏感的Piezo1离子通道刺激来生成和分离高浓度的RBC-EVs。通过对红细胞施加剪切应力或Piezo1激动剂yoda1来生成RBC-EVs。然后,我们研究了Piezo1 RBC-EV生成参数(血细胞比容、处理时间、处理剂量)、分离方法(基于膜的亲和、超滤、有无尺寸排阻色谱的超速离心)和储存条件如何影响RBC-EV的产量和纯度。最后,我们使用压力肌动描记法来确定使用不同方法分离的RBC-EVs如何影响小鼠颈动脉血管舒张。我们的结果表明,在6%血细胞比容下用10 µM yoda1处理红细胞30分钟,并通过超速离心分离RBC-EVs,可将溶血降至最低,使产量和纯度最大化,并产生最一致的RBC-EV制剂。不纯样品中共同分离的污染物而非Piezo1 RBC-EVs可诱导小鼠颈动脉血管舒张。这项工作表明,RBC-EVs可通过Piezo1刺激产生,并且可能在生理流动条件下产生。我们的研究进一步强调了在使用EVs进行机制分析之前表征EV生成和分离参数的重要性,因为RBC-EV纯度会影响功能结果。