巨噬细胞是具有异质性的一群免疫细胞,在病原微生物和组织损伤所引起的炎症反应及消解过程中发挥关键作用.不同的诱导信号可激活巨噬细胞改变其自身的形态和生理特征,表现出显著的可塑性来应对外界环境.借用辅助性T细胞(Th)的概念,从激活方式上将巨噬细胞分为经典激活的巨噬细胞(classically activated macrophages,CAMs或M1)和非经典激活的巨噬细胞(alternatively activated macrophages,AAMs或M2)两大类.M1型巨噬细胞产生促炎症细胞因子,抵抗病原入侵但也造成机体损伤;M2型分泌抗炎症细胞因子,并在组织修复与重建和肿瘤的形成过程中发挥作用.本文介绍了巨噬细胞的激活机制和巨噬细胞极性的关系,重点总结了近年来巨噬细胞极性调控机制方面的最新研究进展,并分析预测了该领域的发展趋势.
Macrophages are a heterogeneous population of immune cells that are essential for the initiation and resolution of pathogen- or tissue damage-induced inflammation. The plasticity of macrophages allows them to respond efficiently and alter their phenotype and physiology in response to environmental cues. Based on T helper type 1 (Thl) and Th2 polarization, macrophages have been classified according to their functional polarization, to either M1 (classic) macrophages, which produce proinflammatory cytokines, boost resistance to pathogens and contribute to tissue destruction, or M2 (alternative) macrophages, which secrete anti-inflammatory cytokines, promote tissue repair and remodeling as well as tumor progression. In this review, we summarize the current knowledge of macrophage activation and the ideas that are under development in the study of macrophage polarization.