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

描述（由申请人提供）：本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，高达42%的人口都有牙齿脱落的经历，并且不成比例地影响少数民族和经济弱势群体。目前最先进的治疗依赖于人造钛/陶瓷牙科植入物，其具有缺点，包括需要显著的外科手术干预、缺乏敏感性、对机械故障和细菌定植的敏感性以及在骨退化或损伤的情况下的限制使用。通过整个牙齿再生来替换失去的牙齿是牙科技术的最终目标之一，并且理想地将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形成，但尚未确定成体上皮细胞的合适来源。我们和其他实验室的最新数据表明，上皮细胞连环蛋白信号的激活是胚胎牙齿发育的关键起始事件，这表明在成年口腔上皮细胞中操纵这一途径可能使它们能够参与从头牙齿发育。本提案的目的是检验这一假设，并描绘牙芽再生的最佳条件从连环蛋白激活的胚胎和成年小鼠口腔细胞和人类细胞系。具体而言，我们将：（1）确定来自携带上皮<$-连环蛋白不可逆激活突变的成年小鼠的口腔细胞是否可以在体外和体内支持牙齿发育;（2）确定激活的<$-连环蛋白的可逆口腔上皮表达是否允许具有正常大小和形状的牙齿从头发育;和（3）确定培养的小鼠和人类成年口腔上皮细胞是否可以启动 在上皮细胞连环蛋白信号传导激活后。这些研究有可能改变我们治疗人类患者牙齿脱落的方法，通过使用患者自身的细胞再生牙齿，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.在美国，牙齿脱落是一个主要的健康问题，在一些州，高达42%的人口都有牙齿脱落的经历，并且不成比例地影响少数民族和经济弱势群体。牙科植入物是目前最先进的治疗牙齿缺失的方法，但容易发生机械故障和感染，并且难以用于骨丢失严重的个体。该提案的目的是开发用于重新激活成人口腔细胞中的胚胎牙齿信号通路的方法，用于天然牙齿及其相关支持组织（包括骨、血管、神经和牙周韧带）的再生，提供改善的功能、敏感性、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.