Department of Biochemistry & Molecular Biology, Nippon Medical School, Bunkyo-ku, Tokyo, Japan.
Department of Disease Biology and Molecular Medicine, Chiba University Graduate School of Medicine, Chuo-ku, Chiba, Japan.
Int Immunol. 2018 Oct 29;30(11):511-528. doi: 10.1093/intimm/dxy054.
Tissue injury triggers a complex series of cellular responses, starting from inflammation activated by tissue and cell damage and proceeding to healing. By clearing cell debris, activating and resolving inflammation and promoting fibrosis, macrophages play key roles in most, if not all, phases of the response to injury. Recent studies of the mechanisms underlying the initial inflammation and later tissue regeneration and repair revealed that macrophages bridge these processes in part by supporting and activating stem/progenitor cells, clearing damaged tissue, remodeling extracellular matrix to prepare scaffolding for regeneration and promoting angiogenesis. However, macrophages also have a central role in the development of pathology induced by failed resolution (e.g. chronic inflammation) and excessive scarring. In this review, we summarize the activities of macrophages in inflammation and healing in response to acute injury in tissues with differing regenerative capacities. While macrophages lead similar processes in response to tissue injury in these tissues, their priorities and the consequences of their activities differ among tissues. Moreover, the magnitude, nature and duration of injury also greatly affect cellular responses and healing processes. In particular, continuous injury and/or failed resolution of inflammation leads to chronic ailments in which macrophage activities may become detrimental.
组织损伤引发了一系列复杂的细胞反应，从组织和细胞损伤激活的炎症开始，进而发展为愈合。巨噬细胞通过清除细胞碎片、激活和解决炎症以及促进纤维化，在损伤反应的大多数（如果不是全部）阶段发挥关键作用。最近对初始炎症以及后来的组织再生和修复的机制研究表明，巨噬细胞通过支持和激活干细胞/祖细胞、清除受损组织、重塑细胞外基质为再生准备支架以及促进血管生成，在这些过程中起到桥梁作用。然而，巨噬细胞在失败的解决（例如慢性炎症）和过度瘢痕形成引起的病理发展中也起着核心作用。在这篇综述中，我们总结了巨噬细胞在具有不同再生能力的组织中对急性损伤的炎症和愈合反应中的作用。虽然巨噬细胞在对这些组织中的组织损伤做出相似的反应，但它们的优先级和活动的后果在不同组织之间有所不同。此外，损伤的程度、性质和持续时间也极大地影响细胞反应和愈合过程。特别是持续的损伤和/或炎症的解决失败会导致慢性疾病，其中巨噬细胞的活动可能会产生有害影响。
