Epithelia in adult mammals exhibit remarkable regenerative capacities owing to the presence of adult stem cells, which self‐renew and differentiate to replace cells lost to normal turnover or injury. The mechanisms supporting tissue homeostasis and injury‐induced repair often differ from each other as well as from those used in embryonic development. Recent studies have also highlighted the phenomenon of cellular plasticity in adult tissues, in which differentiated cells can change fate and even give rise to new stem cell populations to complement the canonical stem cells in promoting repair following injury. Signaling pathways such as WNT, bone morphogenetic protein, and Sonic Hedgehog play critical roles in stem cell maintenance and cell fate decisions across diverse epithelia and conditions, suggesting that conserved mechanisms underlie the regenerative capacity of adult epithelial structures.

中文翻译：

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稳态和修复过程中上皮干细胞自我更新和分化的细胞机制。

由于成年干细胞的存在，成年哺乳动物的上皮细胞显示出显着的再生能力，它们可以自我更新并分化以替换因正常更新或受伤而丢失的细胞。支持组织动态平衡和损伤诱导修复的机制通常彼此不同，也不同于胚胎发育中使用的机制。最近的研究还强调了成人组织中细胞可塑性的现象，其中分化的细胞可以改变命运，甚至产生新的干细胞群，以补充规范的干细胞，促进损伤后的修复。WNT，骨形态发生蛋白和Sonic Hedgehog等信号通路在多种上皮和条件下的干细胞维持和细胞命运决定中起着至关重要的作用，