Harada Hidemitsu, Mitsuyasu Takeshi, Toyono Takashi, Toyoshima Kuniaki
Second Department of Oral Anatomy and Cell Biology, Kyushu Dental College, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu 803-8580, Japan.
Odontology. 2002 Sep;90(1):1-6. doi: 10.1007/s102660200000.
Many tissues and organs maintain a process known as homeostasis, in which cells are replenished as they die as a result of apoptosis or injury. The continuously growing mouse incisors are an excellent model for studying the molecular mechanisms of cell homeostasis, renewal, and repair. We elucidated these mechanisms in mouse incisors by detecting adult stem cells and analyzing the stem cell lineage by bromodeoxyuridine (BrdU) labeling analysis. The stem cells divide slowly, giving rise to a daughter cell that remains in the cervical loop and a second daughter cell that enters the zone of rapidly dividing inner enamel epithelial cells (transit-amplifying cell population). During subsequent rounds of cell division, the latter cells move toward the incisal end and differentiate into ameloblasts that form the enamel matrix. Recent evidence from gene knockout mice suggests that fibroblast growth factor (Fgf10) plays an important role in the formation and maintenance of stem cells in the development of mouse incisors. The role of dental stem cells in odontogenic tumors is discussed.
许多组织和器官维持着一种称为稳态的过程，在此过程中，细胞因凋亡或损伤而死亡时会得到补充。不断生长的小鼠门齿是研究细胞稳态、更新和修复分子机制的极佳模型。我们通过检测成年干细胞并利用溴脱氧尿苷（BrdU）标记分析来分析干细胞谱系，从而阐明了小鼠门齿中的这些机制。干细胞缓慢分裂，产生一个留在颈环的子细胞和另一个进入快速分裂的内釉上皮细胞区（过渡放大细胞群）的子细胞。在随后的细胞分裂轮次中，后一种细胞向切端移动并分化为形成釉质基质的成釉细胞。基因敲除小鼠的最新证据表明成纤维细胞生长因子（Fgf10）在小鼠门齿发育过程中干细胞的形成和维持中起重要作用。文中还讨论了牙干细胞在牙源性肿瘤中的作用。
