Manipulation of beta-catenin signaling in adult oral cells for tooth regeneration

描述（由申请人提供）：该申请涉及广泛的挑战领域（14）干细胞和（11）再生医学，以及特定的挑战主题14- de -101*：口腔和颅面组织细胞的精确重编程和11- de -101：颅面组织再生。该项目的最终目标是建立成人口腔组织生物工程牙齿的方法。牙齿脱落是美国的一个主要健康问题，在一些州，多达42%的人口遭受牙齿脱落的影响，对少数民族和经济上处于不利地位的社区的影响尤为严重。目前最先进的治疗依赖于人工钛/陶瓷牙种植体，其缺点包括需要大量的手术干预，缺乏敏感性，容易发生机械故障和细菌定植，以及在骨骼恶化或损伤的情况下限制使用。通过全牙再生来替代失去的牙齿是牙科技术的最终目标之一，理想情况下，使用成人细胞来完成，以避免围绕使用人类胚胎组织的实际和伦理问题，以及移植排斥问题。虽然成体间充质干细胞可以参与牙芽的形成，但尚未确定成体上皮细胞的合适来源。最近来自我们和其他实验室的数据表明，上皮-catenin信号的激活是胚胎牙齿发育的一个关键启动事件，这表明在成人口腔上皮细胞中操纵这一途径可能使它们能够参与牙齿的新生发育。本研究的目的是验证这一假设，并描述由¿-catenin激活的胚胎和成年小鼠口腔细胞和人类细胞系再生牙芽的最佳条件。具体而言，我们将：(1)确定携带上皮-连环蛋白不可逆激活突变的成年小鼠口腔细胞是否能在体外和体内支持牙齿发育；(2)确定活化的¿-catenin的可逆口腔上皮表达是否允许正常大小和形状的牙齿新生发育；(3)确定培养的小鼠和人成年口腔上皮细胞是否可以启动上皮¿-catenin信号的激活。这些研究有可能改变我们治疗人类患者牙齿脱落的方法，通过使用患者自己的细胞来再生牙齿，使其完全融入患者的组织、循环系统和神经系统，而不是依赖人工合成植入物。7. 牙齿脱落是美国的一个主要健康问题，在一些州，高达42%的人口都有牙齿脱落的问题，对少数民族和经济上处于不利地位的社区的影响尤为严重。牙种植体是目前最先进的治疗缺牙的方法，但容易发生机械故障和感染，并且难以用于严重骨质流失的个体。本提案的目的是开发在成人口腔细胞中重新激活胚胎牙齿信号通路的方法，以再生天然牙齿及其相关支持组织，包括骨，血管，神经和牙周韧带，提供更好的功能，灵敏度，耐久性和外观。

DESCRIPTION (provided by applicant): This application addresses broad Challenge Areas (14) Stem Cells and (11) Regenerative Medicine and the specific Challenge Topics 14-DE-101*: Precise Reprogramming of Cells from Oral and Craniofacial Tissues and 11-DE-101: Craniofacial Tissue Regeneration. The ultimate goal of this project is to establish methods for bioengineering teeth from adult oral tissues. Tooth loss is a major health problem in the USA, experienced by up to 42% of the population in some states and disproportionately affecting minority and economically disadvantaged communities. Current state-of-the-art therapy relies on artificial titanium/ceramic dental implants that suffer from drawbacks including requiring significant surgical intervention, lack of sensitivity, susceptibility to mechanical failure and bacterial colonization, and restricted use in cases of bone deterioration or damage. The replacement of lost teeth by whole tooth regeneration is one of the ultimate goals of dental technology, and will ideally be accomplished using adult cells to avoid practical and ethical issues surrounding the use of human embryonic tissues, and problems of graft rejection. While adult mesenchymal stem cells can participate in tooth bud formation, a suitable source of adult epithelial cells has not been identified. Recent data from our and other labs indicate that activation of epithelial ¿-catenin signaling is a key initiating event in embryonic tooth development, suggesting that manipulation of this pathway in adult oral epithelial cells might render them capable of participating in de novo tooth development. The objective of this proposal is to test this hypothesis, and to delineate the optimal conditions for tooth bud regeneration from ¿-catenin activated embryonic and adult mouse oral cells and human cell lines. Specifically we will: (1) Determine whether oral cells from adult mice carrying an irreversible activating mutation in epithelial ¿-catenin can support tooth development in vitro and in vivo; (2) Determine whether reversible oral epithelial expression of activated ¿-catenin permits de novo development of teeth with normal size and shape; and (3) Determine whether cultured mouse and human adult oral epithelial cells can initiate following activation of epithelial ¿-catenin signaling. These investigations have the potential to alter our approach to treating tooth loss in human patients, by using the patient's own cells to regenerate teeth that become fully integrated into the patient's tissue, circulatory system and nervous system, rather than relying on artificial synthetic implants. 7. Project Narrative Tooth loss is a major health problem in the USA, experienced by up to 42% of the population in some states and disproportionately affecting minority and economically disadvantaged communities. Dental implants are the current state-of-the-art treatment for missing teeth, but are prone to mechanical failure and infections, and are difficult to use in individuals with significant bone loss. The aim of this proposal is to develop methods for reactivating embryonic dental signaling pathways in adult oral cells for regeneration of natural teeth and their associated support tissues, including bone, blood vessels, nerves and periodontal ligament, providing improved function, sensitivity, durability and appearance.