Analysis of extracellular vesicle microRNA profiles reveals distinct blood and lymphatic endothelial cell origins [mRNA]

Extracellular Vesicles (EVs) are crucial mediators of cell-to-cell communication in physiology but also in pathological conditions. Specifically, EVs released from the vasculature into blood were found to be quantitatively and qualitatively different in diseases versus healthy states. However, our understanding on EVs derived from the lymphatic system is still scarce. In this study we compared the mRNA and miRNA expression in blood vascular (BEC) and lymphatic (LEC) endothelial cells. After characterization of the EVs by fluo-triggered flow cytometry, nanoparticle tracking analysis and cryo-EM we utilized small RNA-sequencing to characterize miRNA signatures in the EVs and thereof identify cell-type specific miRNAs in BEC and LEC. We believe that our data provide a solid basis for further functional in vitro and in vivo studies addressing the role of EVs in the blood and lymphatic vasculature. Overall design: Different endothelial cells (especially lymphatic and blood endothelial cells) were used to derive Extracellular vesicles. Conditioned cells were collected after EVs were harvested. Intracellular RNA was used to perform mRNA and smallRNA sequencing.

细胞外囊泡（Extracellular Vesicles，EVs）是生理与病理状态下介导细胞间通讯的关键介质。具体而言，由血管系统释放入血的EVs在疾病状态与健康状态下，其数量与质量均存在显著差异。然而，目前学界对淋巴系统来源EVs的认知仍较为匮乏。本研究对比了血管内皮细胞（blood vascular endothelial cells, BEC）与淋巴管内皮细胞（lymphatic endothelial cells, LEC）的信使RNA（messenger RNA, mRNA）及微小RNA（microRNA, miRNA）表达水平。本研究首先通过荧光触发流式细胞术、纳米颗粒追踪分析及冷冻电镜（cryo-EM）对EVs进行表征，随后利用小RNA测序技术分析EVs中的miRNA表达谱，进而鉴定出BEC与LEC特异性的miRNA。本研究认为，所获数据可为后续探索EVs在血管及淋巴管系统中功能的体外与体内实验研究提供坚实基础。实验整体设计：采用不同内皮细胞（尤其是淋巴管内皮细胞与血管内皮细胞）提取细胞外囊泡；在收获EVs后，收集经条件培养的内皮细胞，提取其胞内RNA以开展mRNA测序及小RNA测序。