Leiden Institute of Chemistry, Leiden University, 2333 CC Leiden, The Netherlands.
Int J Mol Sci. 2021 Apr 14;22(8):4039. doi: 10.3390/ijms22084039.
Macrophages are key multi-talented cells of the innate immune system and are equipped with receptors involved in damage and pathogen recognition with connected immune response guiding signaling systems. In addition, macrophages have various systems that are involved in the uptake of extracellular and intracellular cargo. The lysosomes in macrophages play a central role in the digestion of all sorts of macromolecules and the entry of nutrients to the cytosol, and, thus, the regulation of endocytic processes and autophagy. Simplistically viewed, two macrophage phenotype extremes exist. On one end of the spectrum, the classically activated pro-inflammatory M1 cells are present, and, on the other end, alternatively activated anti-inflammatory M2 cells. A unique macrophage population arises when lipid accumulation occurs, either caused by flaws in the catabolic machinery, which is observed in lysosomal storage disorders, or as a result of an acquired condition, which is found in multiple sclerosis, obesity, and cardiovascular disease. The accompanying overload causes a unique metabolic activation phenotype, which is discussed here, and, consequently, a unifying phenotype is proposed.
巨噬细胞是先天免疫系统中具有多种功能的关键细胞，配备有参与损伤和病原体识别的受体，以及连接的免疫反应指导信号系统。此外，巨噬细胞还具有各种参与细胞外和细胞内货物摄取的系统。巨噬细胞中的溶酶体在消化各种大分子和营养物质进入细胞质方面起着核心作用，从而调节胞吞作用和自噬。简单地说，存在两种巨噬细胞表型极端情况。一种是经典激活的促炎 M1 细胞，另一种是替代性激活的抗炎 M2 细胞。当发生脂质积累时，会出现一种独特的巨噬细胞群体，这种脂质积累可能是由于溶酶体储存障碍中代谢分解机制的缺陷引起的，也可能是多发性硬化症、肥胖症和心血管疾病等获得性疾病的结果。伴随的过载会导致一种独特的代谢激活表型，本文将对此进行讨论，并因此提出一个统一的表型。
