Eosinophils are essential innate immune cells in allergic responses. Accumulating evidence indicates that eosinophils also participate in the pathogenesis of cardiovascular diseases (CVDs). In clinical studies, high blood eosinophil counts and eosinophil cationic protein levels have been associated with an increased risk of CVD, including myocardial infarction (MI), cardiac hypertrophy, atrial fibrillation, abdominal aortic aneurysm (AAA) and atherosclerosis. However, low blood eosinophil counts have also been reported to be a risk factor for MI, heart failure, aortic dissection, AAA, deep vein thrombosis, pulmonary embolism and ischaemic stroke. Although these conflicting clinical observations remain unexplained, CVD status, timing of eosinophil data collection, and tissue eosinophil phenotypic and functional heterogeneities might account for these discrepancies. Preclinical studies suggest that eosinophils have protective actions in MI, cardiac hypertrophy, heart failure and AAA. By contrast, cationic proteins and platelet-activating factor from eosinophils have been shown to promote vascular smooth muscle cell proliferation, vascular calcification, thrombomodulin inactivation and platelet activation and aggregation, thereby exacerbating atherosclerosis, atrial fibrillation, thrombosis and associated complications. Therefore, eosinophils seem to promote calcification and thrombosis in chronic CVD but are protective in acute cardiovascular settings. In this Review, we summarize the available clinical and preclinical data on the different roles of eosinophils in CVD.

嗜酸性粒细胞是过敏反应中必不可少的先天免疫细胞。越来越多的证据表明嗜酸性粒细胞也参与心血管疾病（CVD）的发病机制。在临床研究中，高血液嗜酸性粒细胞计数和嗜酸性粒细胞阳离子蛋白水平与心血管疾病风险增加相关，包括心肌梗塞（MI）、心脏肥大、心房颤动、腹主动脉瘤（AAA）和动脉粥样硬化。然而，据报道，血液嗜酸性粒细胞计数低也是心肌梗死、心力衰竭、主动脉夹层、AAA、深静脉血栓、肺栓塞和缺血性中风的危险因素。尽管这些相互矛盾的临床观察结果仍无法解释，但 CVD 状态、嗜酸性粒细胞数据收集的时间以及组织嗜酸性粒细胞表型和功能异质性可能是这些差异的原因。临床前研究表明，嗜酸性粒细胞对 MI、心脏肥大、心力衰竭和 AAA 具有保护作用。相比之下，来自嗜酸性粒细胞的阳离子蛋白和血小板激活因子已被证明可促进血管平滑肌细胞增殖、血管钙化、血栓调节蛋白失活以及血小板活化和聚集，从而加剧动脉粥样硬化、心房颤动、血栓形成和相关并发症。因此，嗜酸性粒细胞似乎会促进慢性心血管疾病的钙化和血栓形成，但在急性心血管疾病中具有保护作用。在这篇综述中，我们总结了有关嗜酸性粒细胞在 CVD 中不同作用的现有临床和临床前数据。