Macrophages play a major role in the pathogenesis of atherosclerosis. Many studies have shone light on the different phenotypes and functions that macrophages can acquire upon exposure to local cues. The microenvironment of the atherosclerotic plaque contains a plethora of macrophage-controlling factors, such as cytokines, oxidised low-density lipoproteins and cell debris. Previous research has determined macrophage function within the plaque mainly by using immunohistochemistry and bulk analysis. The recent development and rapid progress of single-cell technologies, such as cytometry by time of flight and single-cell RNA sequencing, now enable comprehensive mapping of the wide range of cell types and their phenotypes present in atherosclerotic plaques. In this review we discuss recent advances applying these technologies in defining macrophage subsets residing in the atherosclerotic arterial wall of mice and men. Resulting from these studies, we describe three main macrophage subsets: resident-like, pro-inflammatory and anti-inflammatory foamy TREM2hi macrophages, which are found in both mouse and human atherosclerotic plaques. Furthermore, we discuss macrophage subset-specific markers and functions. More insights into the characteristics and phenotype of immune cells within the atherosclerotic plaque may guide future clinical approaches to treat disease. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

中文翻译：

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单细胞技术定义的动脉粥样硬化中的巨噬细胞亚群。

巨噬细胞在动脉粥样硬化的发病机制中发挥着重要作用。许多研究揭示了巨噬细胞在暴露于局部线索后可以获得的不同表型和功能。动脉粥样硬化斑块的微环境含有大量巨噬细胞控制因子，例如细胞因子、氧化低密度脂蛋白和细胞碎片。先前的研究主要通过免疫组织化学和批量分析来确定斑块内的巨噬细胞功能。单细胞技术的最新发展和快速进步，例如飞行时间细胞计数和单细胞 RNA 测序，现在能够全面绘制动脉粥样硬化斑块中存在的各种细胞类型及其表型。在这篇综述中，我们讨论了应用这些技术来定义小鼠和人类动脉粥样硬化动脉壁中的巨噬细胞亚群的最新进展。根据这些研究，我们描述了三个主要的巨噬细胞亚群：驻留样巨噬细胞、促炎巨噬细胞和抗炎泡沫状 TREM2hi 巨噬细胞，它们在小鼠和人类动脉粥样硬化斑块中都有发现。此外，我们讨论了巨噬细胞亚群特异性标记和功能。对动脉粥样硬化斑块内免疫细胞的特征和表型的更多了解可能会指导未来治疗疾病的临床方法。© 2020 作者。《病理学杂志》由 John Wiley & Sons Ltd 代表大不列颠及爱尔兰病理学会出版。