Abstract：
OBJECTIVE: Flow diverting stents (FDS) are used to treat cerebral aneurysms, by promoting thrombosis and occlusion of the aneurysm sac. However, retreatment is required in some cases, and the biologic basis behind treatment outcome is not known. The goal of this study was to understand how changes in hemodynamic flow after FDS placement affect aneurysmal endothelial cell (EC) activity.
METHODS: Three-dimensional models of patient-specific aneurysms were created to quantify the EC response to FDS placement. Computational fluid dynamic simulations were used to determine the hemodynamic impact of FDS. Two identical models were created for each patient; into one a FDS was inserted. Each model was then populated with human carotid ECs and subjected to patient-specific pulsatile flow for 24 h. ECs were isolated from aneurysm dome from each model and bulk RNA sequencing was performed.
RESULTS: Paired untreated and treated models were created for four patients. Aneurysm dome EC analysis revealed 366 (2.6%) significant gene changes between the untreated and FDS conditions, out of 13909 total expressed genes. Gene set enrichment analysis of the untreated models demonstrated enriched gene ontology terms related to cell adhesion, growth/tensile activity, cytoskeletal organization, and calcium ion binding. In the FDS models, enriched terms were related to cellular proliferation, ribosomal activity, RNA splicing, and protein folding.
CONCLUSIONS: Treatment of cerebral aneurysms with FDS induces significant EC gene transcription changes related to aneurysm hemodynamics in patient-specific in vitro 3D-printed models subjected to pulsatile flow. Further investigation is needed into the relationship between transcriptional change and treatment outcome.
METHODS: Three-dimensional models of patient-specific aneurysms were created to quantify the EC response to FDS placement. Computational fluid dynamic simulations were used to determine the hemodynamic impact of FDS. Two identical models were created for each patient; into one a FDS was inserted. Each model was then populated with human carotid ECs and subjected to patient-specific pulsatile flow for 24 h. ECs were isolated from aneurysm dome from each model and bulk RNA sequencing was performed.
RESULTS: Paired untreated and treated models were created for four patients. Aneurysm dome EC analysis revealed 366 (2.6%) significant gene changes between the untreated and FDS conditions, out of 13909 total expressed genes. Gene set enrichment analysis of the untreated models demonstrated enriched gene ontology terms related to cell adhesion, growth/tensile activity, cytoskeletal organization, and calcium ion binding. In the FDS models, enriched terms were related to cellular proliferation, ribosomal activity, RNA splicing, and protein folding.
CONCLUSIONS: Treatment of cerebral aneurysms with FDS induces significant EC gene transcription changes related to aneurysm hemodynamics in patient-specific in vitro 3D-printed models subjected to pulsatile flow. Further investigation is needed into the relationship between transcriptional change and treatment outcome.
摘要：
目的：分流支架（FDS）用于治疗脑动脉瘤，通过促进动脉瘤囊的血栓形成和闭塞。然而,在某些情况下需要再治疗，治疗结果背后的生物学基础尚不清楚。这项研究的目的是了解FDS放置后血液动力学流量的变化如何影响动脉瘤内皮细胞（EC）活性。
方法：创建患者特定动脉瘤的三维模型以量化EC对FDS放置的反应。使用计算流体动力学模拟来确定FDS的血液动力学影响。为每个患者创建两个相同的模型；将FDS插入其中。然后将每个模型填充人颈动脉ECs并经历患者特异性脉动流24小时。从每个模型的动脉瘤穹顶分离ECs并进行批量RNA测序。
结果:为4名患者创建未治疗和治疗的配对模型。动脉瘤圆顶EC分析显示，未治疗和FDS条件之间有366（2.6％）显着的基因变化，共表达基因13909个。未经处理的模型的基因集富集分析显示了与细胞粘附相关的丰富的基因本体论术语，生长/拉伸活性，细胞骨架组织，和钙离子结合。在FDS模型中，富集的术语与细胞增殖有关，核糖体活性，RNA剪接,和蛋白质折叠。
结论：在患者特异性体外3D打印模型中，用FDS治疗脑动脉瘤可诱导与动脉瘤血流动力学相关的显著EC基因转录变化。需要进一步研究转录变化与治疗结果之间的关系。
方法：创建患者特定动脉瘤的三维模型以量化EC对FDS放置的反应。使用计算流体动力学模拟来确定FDS的血液动力学影响。为每个患者创建两个相同的模型；将FDS插入其中。然后将每个模型填充人颈动脉ECs并经历患者特异性脉动流24小时。从每个模型的动脉瘤穹顶分离ECs并进行批量RNA测序。
结果:为4名患者创建未治疗和治疗的配对模型。动脉瘤圆顶EC分析显示，未治疗和FDS条件之间有366（2.6％）显着的基因变化，共表达基因13909个。未经处理的模型的基因集富集分析显示了与细胞粘附相关的丰富的基因本体论术语，生长/拉伸活性，细胞骨架组织，和钙离子结合。在FDS模型中，富集的术语与细胞增殖有关，核糖体活性，RNA剪接,和蛋白质折叠。
结论：在患者特异性体外3D打印模型中，用FDS治疗脑动脉瘤可诱导与动脉瘤血流动力学相关的显著EC基因转录变化。需要进一步研究转录变化与治疗结果之间的关系。
