Stem cells (SCs) maintain tissue homeostasis and repair wounds. Despite marked variation in tissue architecture and regenerative demands, SCs often follow similar paradigms in communicating with their microenvironmental “niche” to transition between quiescent and regenerative states. Here we use skin epithelium and skeletal muscle—among the most highly-stressed tissues in our body—to highlight similarities and differences in niche constituents and how SCs mediate natural tissue rejuvenation and perform regenerative acts prompted by injuries. We discuss how these communication networks break down during aging and how understanding tissue SCs has led to major advances in regenerative medicine.

干细胞（SC）维持组织稳态并修复伤口。尽管组织结构和再生需求存在显着差异，但 SC 在与微环境“利基”进行通信以在静止状态和再生状态之间转换时通常遵循类似的范式。在这里，我们使用皮肤上皮和骨骼肌（我们体内压力最大的组织）来强调生态位成分的相似性和差异，以及 SC 如何介导自然组织再生并执行由损伤引起的再生行为。我们讨论这些通信网络在衰老过程中如何崩溃，以及了解组织干细胞如何导致再生医学的重大进展。