Lisi S, Peterková R, Peterka M, Vonesch J L, Ruch J V, Lesot H
INSERM U424, Faculté de Medecine, Strasbourg, France.
Connect Tissue Res. 2003;44 Suppl 1:167-70.
The terminal differentiation of odontoblasts is controlled by the inner dental epithelium (IDE) and occurs according to a tooth-specific pattern. It requires temporospatially regulated epigenetic signaling and the expression of specific competence. The patterning of cusp formation was compared with that of odontoblast differentiation in the first lower molar in mice. Histology, immunostaining, and three dimensional reconstructions were completed by experimental approaches in vitro. The mesenchyme controls the pattern of cusp formation. During the cap-bell transition in the molar, a subpopulation of nondividing IDE cells from the enamel knot (EK) undergo a tooth-specific segregation in as many subpopulations as cusps will form. Epithelial cell-basement membrane interactions seem to be involved in the segregation of EK cells. The timing and spatial pattern of the segregation of EK cells correlate with cusps formation. However, the temporal pattern of odontoblast terminal differentiation is different. This discrepancy might result from cusp-specific differences either in the timing of the initiation of odontoblast terminal differentiation and/or in cell proliferation kinetics.
成牙本质细胞的终末分化受内釉上皮（IDE）控制，并按照牙齿特异性模式发生。它需要时空调节的表观遗传信号和特定能力的表达。将小鼠第一下颌磨牙中牙尖形成的模式与成牙本质细胞分化的模式进行了比较。通过体外实验方法完成了组织学、免疫染色和三维重建。间充质控制牙尖形成的模式。在磨牙从帽状期向钟状期转变过程中，来自釉结（EK）的一群不分裂的IDE细胞会进行与将要形成的牙尖数量相同的牙齿特异性分离。上皮细胞-基底膜相互作用似乎参与了EK细胞的分离。EK细胞分离的时间和空间模式与牙尖形成相关。然而，成牙本质细胞终末分化的时间模式不同。这种差异可能是由于成牙本质细胞终末分化起始时间和/或细胞增殖动力学方面的牙尖特异性差异所致。
