The Research Center for Digestive Tract and Liver Diseases, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv 64239, Israel.
Annu Rev Immunol. 2015;33:643-75. doi: 10.1146/annurev-immunol-032414-112220.
Macrophages are myeloid immune cells that are strategically positioned throughout the body tissues, where they ingest and degrade dead cells, debris, and foreign material and orchestrate inflammatory processes. Here we review two major recent paradigm shifts in our understanding of tissue macrophage biology. The first is the realization that most tissue-resident macrophages are established prenatally and maintained through adulthood by longevity and self-renewal. Their generation and maintenance are thus independent from ongoing hematopoiesis, although the cells can be complemented by adult monocyte-derived macrophages. Second, aside from being immune sentinels, tissue macrophages form integral components of their host tissue. This entails their specialization in response to local environmental cues to contribute to the development and specific function of their tissue of residence. Factors that govern tissue macrophage specialization are emerging. Moreover, tissue specialization is reflected in discrete gene expression profiles of macrophages, as well as epigenetic signatures reporting actual and potential enhancer usage.
巨噬细胞是髓系免疫细胞，它们在全身组织中处于战略位置，吞噬和降解死亡细胞、碎片和外来物质，并协调炎症过程。在这里，我们回顾了我们对组织巨噬细胞生物学理解的两个主要最新范式转变。第一个是认识到大多数组织驻留巨噬细胞是在产前建立的，并通过长寿和自我更新维持到成年期。因此，它们的产生和维持与持续的造血无关，尽管细胞可以通过成年单核细胞衍生的巨噬细胞来补充。其次，除了作为免疫哨兵外，组织巨噬细胞还是其宿主组织的组成部分。这需要它们对局部环境线索作出专门的反应，以促进其所在组织的发育和特定功能。控制组织巨噬细胞特化的因素正在出现。此外，组织特化反映在巨噬细胞离散的基因表达谱中，以及报告实际和潜在增强子使用的表观遗传特征。
