晚期静脉移植失败是由内皮细胞（EC）损伤和炎症引起的内膜增厚所致，从而促进了血管平滑肌细胞（VSMC）的去分化、迁移和增殖。不磷酸化的PRH（富含脯氨酸的DNA结合蛋白）S163C:S177C具有增强稳定性和持续的抗有丝分裂作用。因此，我们研究了经腺病毒输送的PRH S163C:S177C蛋白是否通过VSMC表型修饰减轻内膜增厚，而不会对EC造成不良影响。PRH S163C:S177C在体外（人难管静脉-VSMCs和人难管静脉-ECs）和体内（结扎小鼠颈动脉）通过腺病毒表达。使用西方印迹分析的收缩丝蛋白和胶原基质收缩量对增殖、迁移和细胞凋亡进行了定量化和鉴定表型。使用VCAM(血管细胞粘附蛋白)-1、ICAM（细胞间粘附分子）-1、白细胞介素-6和单核细胞趋化因子-1测量和单核细胞粘附来定量EC炎症。接下来，利用下一代测序技术鉴定了PRH作用的新下游介体，这些介质和内膜增厚被在体内进行研究。PRH S163C:S177C与病毒对照相比，在人难管静脉-VSMCs中抑制了增殖、迁移和凋亡，并促进了收缩表型（增强收缩丝蛋白和胶原基质收缩量）。在人难管静脉-ECs中表达PRH S163C:S177C显著减少了细胞凋亡，而对细胞增殖和迁移没有影响，同时降低了TNF（肿瘤坏死因子）-α诱导的VCAM-1和ICAM-1以及单核细胞的黏附，抑制了白细胞介素-6和单核细胞趋化因子-1的蛋白水平。在结扎小鼠颈动脉中表达PRH S163C:S177C显著阻碍了颈动脉结扎引起的新内膜增殖和增厚，而不影响内皮覆盖。下一代测序技术揭示了STAT- 1（信号转导和转录激活因子1）和HDAC-9（组蛋白去乙酰化酶9）作为PRH作用的介质，并得到了体内和体外分析的支持。我们观察到PRH S163C:S177C至少部分通过STAT-1和HDAC-9信号途径抑制了VSMC增殖和迁移、促进了VSMC分化，同时促进了内皮修复和抗炎特性。这些发现强调了PRH S163C:S177C在抑制内膜增厚、减少晚期静脉移植失败的同时保护内皮功能的潜力。

Late vein graft failure is caused by intimal thickening resulting from endothelial cell (EC) damage and inflammation which promotes vascular smooth muscle cell (VSMC) dedifferentiation, migration, and proliferation. Nonphosphorylatable PRH (proline-rich homeodomain) S163C:S177C offers enhanced stability and sustained antimitotic effect. Therefore, we investigated whether adenovirus-delivered PRH S163C:S177C protein attenuates intimal thickening via VSMC phenotype modification without detrimental effects on ECs.PRH S163C:S177C was expressed in vitro (human saphenous vein-VSMCs and human saphenous vein-ECs) and in vivo (ligated mouse carotid arteries) by adenoviruses. Proliferation, migration, and apoptosis were quantified and phenotype was assessed using Western blotting for contractile filament proteins and collagen gel contraction. EC inflammation was quantified using VCAM (vascular cell adhesion protein)-1, ICAM (intercellular adhesion molecule)-1, interleukin-6, and monocyte chemotactic factor-1 measurement and monocyte adhesion. Next Generation Sequencing was utilized to identify novel downstream mediators of PRH action and these and intimal thickening were investigated in vivo.PRH S163C:S177C inhibited proliferation, migration, and apoptosis and promoted contractile phenotype (enhanced contractile filament proteins and collagen gel contraction) compared with virus control in human saphenous vein-VSMCs. PRH S163C:S177C expression in human saphenous vein-ECs significantly reduced apoptosis, without affecting cell proliferation and migration, while reducing TNF (tumor necrosis factor)-α-induced VCAM-1 and ICAM-1 and monocyte adhesion and suppressing interleukin-6 and monocyte chemotactic factor-1 protein levels. PRH S163C:S177C expression in ligated murine carotid arteries significantly impaired carotid artery ligation-induced neointimal proliferation and thickening without reducing endothelial coverage. Next Generation Sequencing revealed STAT-1 (signal transducer and activator of transcription 1) and HDAC-9 (histone deacetylase 9) as mediators of PRH action and was supported by in vitro and in vivo analyses.We observed PRH S163C:S177C attenuated VSMC proliferation, and migration and enhanced VSMC differentiation at least in part via STAT-1 and HDAC-9 signaling while promoting endothelial repair and anti-inflammatory properties. These findings highlight the potential for PRH S163C:S177C to preserve endothelial function whilst suppressing intimal thickening, and reducing late vein graft failure.