Vera Moulton Wall Center for Pulmonary Vascular Diseases.
Stanford Cardiovascular Institute.
Am J Respir Crit Care Med. 2022 Oct 15;206(8):1019-1034. doi: 10.1164/rccm.202102-0446OC.
The role of neutrophils and their extracellular vesicles (EVs) in the pathogenesis of pulmonary arterial hypertension is unclear. To relate functional abnormalities in pulmonary arterial hypertension neutrophils and their EVs to mechanisms uncovered by proteomic and transcriptomic profiling. Production of elastase, release of extracellular traps, adhesion, and migration were assessed in neutrophils from patients with pulmonary arterial hypertension and control subjects. Proteomic analyses were applied to explain functional perturbations, and transcriptomic data were used to find underlying mechanisms. CD66b-specific neutrophil EVs were isolated from plasma of patients with pulmonary arterial hypertension, and we determined whether they produce pulmonary hypertension in mice. Neutrophils from patients with pulmonary arterial hypertension produce and release increased neutrophil elastase, associated with enhanced extracellular traps. They exhibit reduced migration and increased adhesion attributed to elevated β1-integrin and vinculin identified by proteomic analysis and previously linked to an antiviral response. This was substantiated by a transcriptomic IFN signature that we related to an increase in human endogenous retrovirus K envelope protein. Transfection of human endogenous retrovirus K envelope in a neutrophil cell line (HL-60) increases neutrophil elastase and IFN genes, whereas vinculin is increased by human endogenous retrovirus K deoxyuridine triphosphate diphosphatase that is elevated in patient plasma. Neutrophil EVs from patient plasma contain increased neutrophil elastase and human endogenous retrovirus K envelope and induce pulmonary hypertension in mice, mitigated by elafin, an elastase inhibitor. Elevated human endogenous retroviral elements and elastase link a neutrophil innate immune response to pulmonary arterial hypertension.
中性粒细胞及其细胞外囊泡（EVs）在肺动脉高压发病机制中的作用尚不清楚。本研究旨在将肺动脉高压患者中性粒细胞及其 EVs 的功能异常与蛋白质组学和转录组学分析揭示的机制联系起来。评估了肺动脉高压患者和对照个体中性粒细胞的弹性蛋白酶产生、细胞外陷阱释放、黏附和迁移。对蛋白质组学分析进行了功能失调的解释，转录组数据用于寻找潜在的机制。从肺动脉高压患者的血浆中分离出 CD66b 特异性中性粒细胞 EVs，并确定它们是否在小鼠中产生肺动脉高压。肺动脉高压患者的中性粒细胞产生和释放增加的中性粒细胞弹性蛋白酶，与增强的细胞外陷阱有关。它们表现出迁移减少和黏附增加，这归因于蛋白质组学分析确定的β1 整合素和 vinculin 的升高，先前与抗病毒反应有关。这一点通过我们与人类内源性逆转录病毒 K 包膜蛋白增加相关的 IFN 特征转录组得到证实。在中性粒细胞细胞系（HL-60）中转染人类内源性逆转录病毒 K 包膜增加中性粒细胞弹性蛋白酶和 IFN 基因，而 vinculin 则由患者血浆中升高的人类内源性逆转录病毒 K 脱氧三磷酸核苷二磷酸酶增加。患者血浆中的中性粒细胞 EV 含有增加的中性粒细胞弹性蛋白酶和人类内源性逆转录病毒 K 包膜，并在小鼠中诱导肺动脉高压，弹性蛋白酶抑制剂 elafin 可减轻这种情况。 升高的人类内源性逆转录病毒元件和弹性蛋白酶将中性粒细胞先天免疫反应与肺动脉高压联系起来。
