EPAS1-BHLHE40介导的炎症反应在低氧肺血管重构中的作用及机制研究

低氧时肺血管内皮细胞介导炎症反应增强，是低氧肺血管重构的重要机制。EPAS1是调控低氧肺血管重构的关键转录因子，特异性敲除内皮细胞EPAS1可逆转EGLN1ec-/-和低氧诱导的肺血管重构，其作用机制尚不明确。我们前期研究发现，干扰EPAS1可抑制低氧诱导的肺动脉内皮细胞（HPAECs）炎症介质表达升高，表明内皮细胞EPAS1可调节炎症介质表达，参与低氧肺血管重构。CHIP-seq和RNA-seq联合分析提示，BHLHE40可受EPAS1直接调控，参与低氧HPAECs炎症反应增强。本项目旨在明确内皮细胞EPAS1和BHLHE40在肺血管炎症反应及低氧肺血管重构中的作用，并采用cCas9-原位捕获等新技术，寻找BHLHE40、CCL5和ICAM1的转录调控复合物，深入探讨EPAS1调控BHLHE40及其下游炎症介质的转录调控机制，阐明内皮细胞EPAS1调控低氧肺血管重构的分子机制。

The enhancement of inflammatory response mediated by pulmonary vascular endothelial cells during hypoxia is an important mechanism of hypoxic pulmonary vascular remodeling. EPAS1 is a key transcription factor in regulating the hypoxic pulmonary vascular remodeling. Knockout of endothelial cell EPAS1 can reverse pulmonary vascular remodeling in hypoxia and EGLN1ec-/- mice, but its mechanism is not clear. Our previous study found that interference with EPAS1 could inhibit the increased expression of inflammatory mediators induced by hypoxia in pulmonary artery endothelial cells (HPAECs), indicating that endothelial cells EPAS1 can regulate the expression of inflammatory mediators and participate in hypoxic pulmonary vascular remodeling. The combined analysis of CHIP-seq and RNA-seq suggested that BHLHE40 could be directly regulated by EPAS1 and participated in the enhancement of inflammatory response in hypoxic HPAECs. The purpose of this study was to investigate the role of endothelial cell EPAS1 and BHLHE40 in pulmonary vascular inflammation and hypoxic pulmonary vascular remodeling, to search for transcriptional regulatory complexes of BHLHE40, CCL5 and ICAM1 by new techniques such as cCas9- in situ capture, to investigate the transcriptional regulation mechanism of BHLHE40 by EPAS1 and its downstream inflammatory mediators, and to elucidate the molecular mechanism of the regulation in hypoxic pulmonary vascular remodeling by EPAS1 in endothelial cells.