Indction of odontoblasts from cranial neural crest stem cells

神经嵴（NC）细胞在e9.0时从神经褶皱背端生成。NC细胞分为两个种群；颅神经嵴（CNC）和干神经嵴（TNC）。CNC可分化为多种细胞系，包括成骨细胞、软骨细胞和成牙细胞。此外，已知CNC参与器官发生，如颅面包含颌骨和牙齿，以及胸腺。然而，这些NC细胞的特性尚未明确。因此，我们评估了这些NC细胞的存在、分布和分化潜力。此外，我们尝试用GFP技术制作一个检测CNC向成牙细胞分化的系统。我们的研究结果如下：1)我们使用在神经嵴细胞中表达Cre基因的P0-Cre小鼠，我们可以将神经嵴源性细胞追踪为表达lacz的细胞。利用该系统，我们明确了NC在胸腺中的存在、分布和分化潜力。此外，我们通过流式细胞术评估NC细胞的特征。2)接下来，利用这些系统，我们明确了大约70%的牙芽间充质细胞是由NC来源的细胞组成的，并且这些NC细胞在牙芽中大量表达PFDGFRα，整合素αV， CD44.3)。我们发现牙芽中的NC来源细胞不仅可以分化成成牙细胞，还可以分化成软骨细胞和成骨细胞。4)在牙本质唾液磷蛋白（DSPP）控制下，制备了3株携带GFP的转基因小鼠。然而，我们没有得到在成牙细胞中表达GFP的转基因小鼠。

Murine neural crest(NC) cells are generated from dorsal tip of neural folds at E 9.0. NC cells are divided into two populations ; cranial neural crest(CNC) and trunk neural crest(TNC). CNC can differentiate into several cell lineages containing osteoblasts, chondrocytes and odontoblasts. Furthermore, it is known that CNC participate in organogenesis such as cranioface containing jaws and teeth, and thymus. However, characteristics of these NC cells have not been clarified. Therefore, we assessed the presence, distribution and potential for differentiation of these NC cells. In addition, we tried to make a system to detect the differentiation of CNC into odontoblasts by using GFP.We show results of our research as follows :1)We used P0-Cre mice, which express Cre gene in the neural crest cells, and we can trace neural crest-derived cells as LacZ-expressing cells. Using this system, we clarified the presence, distribution and potential for differentiation of NC in the thymus. Furthermore, we assessed the characteristics of NC cells by flow cytometry.2)Next, using these systems, we clarified that about 70% mesenchymal cells of tooth buds were composed of NC-derived cells, and large numbers of these NC cells in the tooth buds expressed PFDGFRα, integrin αV, CD44.3)We found that NC-derived cells in the tooth buds could differentiate into not only odontoblasts but also chondrocytes and osteoblasts.4)We made three lines of transgenic mice carrying GFP under the control of Dentin sialophosphoprotein(DSPP). However, we didn't get transgenic mice that express GFP in odontoblasts.