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

上皮内陷是牙齿早期发育的重要特征。在本研究中，我们首先以人正常口腔上皮细胞(OECs)和牙髓干细胞(DPSCs)为材料，利用组织工程学方法构建了一个三维模型来表达上皮内陷样结构。OEC-DPSC与基质细胞共培养后，可见典型的上皮细胞内陷和基质细胞凝聚。上皮内陷相关分子CD44、E-钙粘素和间质凝聚涉及分子，N-钙粘素和Msx1在组织模型中高水平表达，提示上皮内陷具有功能性。我们的结果表明，在一定条件下，OECs和DPSCs在基质上共培养可以建立上皮样凹陷模型。该模型可作为上皮-间充质相互作用和牙齿再生的潜在研究工具。

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.