Cell-based scaffold-less three-dimensional construct, a model for dentinogenesis

据估计，在西方国家，85%的成年人接受过牙科治疗，到50岁时，平均成年人失去了12颗牙齿。目前正在设计诱导牙本质修复和再生的方法，并且最近的研究工作针对用于牙齿替换的组织工程牙齿。为了成功地诱导牙本质再生或在体外创造牙齿，需要更好地了解所涉及的细胞。本项目的目标是建立一个相关的模型来研究体外牙本质形成的假设，即通过允许牙髓干细胞在体外产生自己的三维结构，我们将创建一个相关的模型系统，用于体外研究成牙本质细胞微环境和牙本质基质组装。干细胞存在于牙髓中，可以分化为成牙本质细胞用于牙本质修复。在原位，成牙本质细胞存在于它们分泌和重塑自身的三维（3D）结构中。因此，用单层牙髓细胞或人工衍生支架进行的研究不能模拟这些细胞的真实微环境。最近的文献报道显示，骨髓基质细胞具有合成和重塑自身基质的能力，以产生圆柱形骨样结构。这些构建体仅由骨髓基质细胞及其新产生的自体细胞外基质组成。该技术将用于指导牙髓细胞在体外创建类似的无支架3D构建体。将研究这些构建体的分子和结构特性，并与骨髓基质细胞产生的分子和结构特性进行比较。然后将由骨髓基质细胞和牙髓细胞形成的工程化组织皮下植入免疫受损的小鼠中，以研究体内环境的影响，并进一步验证牙本质样构建体的产生。 公共卫生相关性：据估计，在西方国家，85%的成年人都接受过牙科治疗，到50岁时，平均每个成年人已经失去了12颗牙齿。目前正在设计诱导牙本质修复和再生的方法，并且最近的研究工作针对用于牙齿替换的组织工程牙齿。为了成功地诱导牙本质再生或在体外创造牙齿，需要更好地了解所涉及的细胞。

DESCRIPTION (provided by applicant): It is estimated that 85% of adults in Western countries have endured dental treatment and by the age of 50 the average adult has lost 12 teeth. Methods are being designed to induce dentin repair and regeneration and more recent research efforts are targeted toward tissue engineering teeth for tooth replacement. In order to successfully induce dentin regeneration or create a tooth in vitro a better understanding of the cells involved needs to be acquired. The goal of this project is to create a relevant model to study dentinogenesis in vitro with the hypothesis that by allowing dental pulp stem cells to generate their own 3D structure in vitro we will create a relevant model system for in vitro studies of the odontoblastic microenvironment and dentin matrix assembly. Stem cells reside in dental pulp that can differentiate to odontoblasts for dentin repair. In situ, odontoblasts reside in three dimensional (3D) structures that they secrete and remodel themselves. Therefore, studies performed with dental pulp cells in a monolayer or with artificially derived scaffolding do not mimic the true microenvironment of these cells. Recent reports in the literature have shown the ability for bone marrow stromal cells to synthesize and remodel their own matrix to create cylindrical bone-like construct. These constructs only consist of the bone marrow stromal cells and their newly made autogenous extracellular matrix. This technology will be utilized to direct the dental pulp cells to create similar scaffold less 3D constructs in vitro. The molecular and structural properties of these constructs will be studied and compared to those created by bone marrow stromal cells. The engineered tissues formed by bone marrow stromal cells and dental pulp cells will then be subcutaneously implanted into immuno-compromised mice to study the effects of the in vivo environment and further verify the creation of dentin- like construct. Public Health Relevance: It is estimated that 85% of adults in Western countries have endured dental treatment and by the age of 50 the average adult has lost 12 teeth. Methods are being designed to induce dentin repair and regeneration and more recent research efforts are targeted toward tissue engineering teeth for tooth replacement. In order to successfully induce dentin regeneration or create a tooth in vitro a better understanding of the cells involved needs to be acquired.