Cell elasticity determines macrophage function.

We report that macrophage elasticity plays a dominant role in bacterial phagocytosis, release of TNF-alpha, and production of reactive oxygen species. We show that macrophage elasticity is modulated by mechanical factors including substrate rigidity and substrate stretch. Changes in macrophage elasticity are dependent upon the degree of actin polymerization, and mediated in part through small rhoGTPase activity. Moreover, the functional effects of macrophage elasticity are not predicted by gene expression profiles. Murine RAW 267.4 macrophages were separately grown on 2 matrix stiffness levels (1200, 150000 Pascals) for 0, 2, 6, 18 hours with 3 replicate sample experiments per condition. Total RNA extracted from the cells and profiled by microarrays. Keywords: Murine RAW 267.4 macrophage, matrix stiffness, phagocytosis, cell elasticity.

本研究表明，巨噬细胞（macrophage）的弹性在细菌吞噬作用、肿瘤坏死因子-α（TNF-alpha）释放以及活性氧（reactive oxygen species）生成中发挥主导作用。本研究证实，巨噬细胞弹性受基质刚度与底物拉伸等机械因素调控。巨噬细胞弹性的变化依赖于肌动蛋白聚合程度，并部分通过小rhoGTP酶（rhoGTPase）活性介导。此外，巨噬细胞弹性的功能效应无法通过基因表达谱进行预测。本研究将小鼠RAW 267.4巨噬细胞（Murine RAW 267.4 macrophages）分别培养于两种基质刚度水平（1200、150000帕斯卡（Pascals））的环境中，培养时长分别为0、2、6、18小时，每个条件设置3次重复实验。提取细胞总RNA，并通过微阵列（microarray）技术完成基因表达谱分析。关键词：小鼠RAW 267.4巨噬细胞、基质刚度、吞噬作用、细胞弹性。