Reconstructing tooth early stage using human cells and screening the potential Chinese herbs for tissue-regeneration

上皮内陷是早期牙齿发育的关键特征。在本研究中，我们首先利用人正常口腔上皮细胞（OECs）和牙髓干细胞（DPSCs），通过组织工程技术构建了一个三维模型来表征上皮内陷样结构。基质上OEC-DPSC共培养显示典型的上皮细胞内陷和下层间充质细胞的三维凝结。上皮内陷相关分子CD44和E-cadherin以及间质凝聚相关分子N-cadherin和Msx1在组织模型中高水平表达，提示上皮内陷是功能性的。我们的结果表明，在一定条件下，在基质上共同培养OECs和DPSCs可以构建上皮内翻样模型。该模型可作为研究上皮-间质相互作用和牙齿再生的潜在工具。

Epithelium invagination is the key feature of early tooth development. In this study, we first built a three dimensional model to represent epithelium invagination-like structure by tissue engineering using human normal oral epithelial cells(OECs) and dental pulp stem cells(DPSCs). OEC-DPSC co-cultures on matrigel showed typical invagination of epithelial cells and condensation of the underlying mesenchymal cells in a three-dimensional manner. Epithelial invagination related molecules, CD44 and E-cadherin, and mesenchymal condensation involved molecules, N-cadherin and Msx1 expressed at a high level in the tissue model, suggesting the epithelial invagination is functional. Our results suggest that co-cultivated OECs and DPSCs on matrigel under certain conditions can build an epithelium invagination-like model. This model might be explored as a potential research tool for epithelial-mesenchymal interaction and tooth regeneration.