Regulation of Wnt signaling in tooth development and regeneration

Wnt信号在牙齿发育和再生中的调节

• 批准号: 8855271
• 负责人: Sarah E. Millar
• 金额: $ 40万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8855271
• 关键词: 3-Dimensional; Accidents; Adult; Affect; Biomedical Engineering; Blood Vessels; Cell Line; Cell Polarity; Cells; Data; Defect; Dental; Dental Enamel; Dental Implants; Development; Ectodermal Dysplasia; Embryo; Endogenous Factors; Epithelial; Epithelial Cells; Epithelium; Failure; Family; Family member; Genes; Genetic; Goals; Growth; Health; Human; Hypodontia; Image; Implant; In Vitro; Incisor; Individual; Infection; Inherited; Jaw; Life; Ligands; Light; Mandible; Mechanics; Mediating; Mesenchymal Stem Cells; Mesenchyme; Microfluidics; Molar tooth; Morphogenesis; Movement; Mus; Mutation; Natural regeneration; Nerve; Odontogenesis; Operative Surgical Procedures; Oral; Pathway interactions; Patients; Pattern; Phenotype; Plant Roots; Play; Population; Property; Proteins; Publishing; Recombinants; Regulation; Relative (related person); Reporter; Rodent; Role; Shapes; Signal Transduction; Site; Staging; Structure; Syndrome; System; Testing; Tooth Germ; Tooth Loss; Tooth structure; WNT10A gene; Wnt proteins; base; beta catenin; bone; bone loss; cell motility; implantation; in vivo; inhibitor/antagonist; loss of function; mouse crinkled protein; mutant; oral tissue; receptor; research study; tooth cusp

DESCRIPTION (provided by applicant): Tooth loss through decay or accident is a major health problem in the USA, and genetic oligodontia occurs in almost 1% of the population. Current therapies rely on surgical implants that suffer from lack of sensitivity, mechanical failur and restricted utility in cases of bone loss. A long term goal of dental bioengineering is to use a patient's own cells for in vitro regeneration of tooth buds that can develop into normally functioning teeth following implantation. Recent progress towards this goal includes successful regeneration of rodent tooth buds from dissociated embryonic dental cells, or embryonic dental epithelia combined with adult mesenchymal stem cells, and implantation of these reconstructs to produce tooth structures that are innervated and vascularized. However, the sizes and shapes of these reconstructed structures are variable, indicating a need to identify endogenous factors that control these properties and could be applied in bioengineering strategies. Mutations of Wnt/beta-catenin pathway components in human patients are associated with dental defects. In particular, mutations in WNT10A are present in more than 50% of congenital non-syndromic hypodontia cases, as well as in a subset of ectodermal dysplasia syndromes. Genetic loss of function experiments in mice reveal requirements for Wnt/beta-catenin signaling at early stages of tooth development, and for formation of both cusp and root structures. Conversely, forced activation of oral epithelial beta-catenin in mouse embryos activates a cascade of downstream dental regulators, stimulating continuous tooth development, and in adults causes formation of embryonic-like tooth buds from incisor epithelia. The structures resulting from embryonic or adult activation of oral epithelial beta-catenin are, respectively, unicuspid, or ca mineralize but do not erupt. Thus, Wnt signaling must be tightly controlled for normal tooth morphogenesis. Wnt/beta-catenin activity is modulated by secreted antagonists, and by competition with alternate, beta-catenin independent pathways that are activated by specific combinations of Wnt ligands, receptors and co-factors. Based on published data and our preliminary studies we hypothesize that Wnt10a and its relative Wnt10b promote tooth development and molar cusp formation by activating beta-catenin signaling, and compete with secreted Sostdc1, Wif1 and Dkk family inhibitors to pattern tooth and cusp development. We further hypothesize that the Wnt receptor Fzd2 mediates non- canonical signaling by Wnt5a, which antagonizes the beta-catenin pathway and plays a critical role in tooth growth and cusp formation. We will test these hypotheses using genetic loss of function and rescue experiments and in vitro approaches. We will further utilize spatially and temporally-controlled delivery systems to determine whether recombinant WNT10A and Wnt10B proteins can be used to promote, and SOSTDC1, WIF1 and DKK proteins to inhibit, growth and cusp formation in embryonic tooth germs and tooth reconstructs in 3-D culture. Results from these experiments will suggest potential strategies for bioengineering teeth of defined size and shape, and for treating inherited conditions that affect tooth development.

描述（由申请人提供）：在美国，通过衰减或事故的牙齿脱落是一个主要的健康问题，遗传性寡头发生在几乎1％的人群中。当前的疗法依赖于缺乏敏感性，机械失败和限制性遗产的手术植入物。牙齿生物工程的一个长期目标是使用患者自己的细胞在体外再生牙齿芽，这些牙齿芽可以在植入后正常发挥作用。实现该目标的最新进展包括从分离的胚胎牙科细胞中成功再生啮齿动物的牙芽，或结合成人间充质干细胞的胚胎牙皮上皮细胞，以及这些重建的植入以产生被支配和血管化的牙齿结构。但是，这些重建结构的大小和形状是可变的，表明需要识别控制这些特性的内源性因素，并且可以在生物工程策略中应用。人类患者中Wnt/β-catenin途径成分的突变与牙齿缺陷有关。特别是，在超过50％的先天性非综合性下降症病例以及外胚层发育不良综合征的一部分中，Wnt10a中的突变存在。小鼠中功能实验的遗传丧失揭示了在牙齿发育的早期阶段对Wnt/β-catenin信号传导的需求，以及形成尖和根结构的需求。相反，小鼠胚胎中口服上皮β-catenin的强迫激活激活了下游牙齿调节剂的级联反应，刺激连续的牙齿发育，成年人导致从切牙上皮的胚胎形成胚胎样的牙齿芽。口服上皮β-catenin产生的结构分别是Unicuspid或CA矿化但不爆发的结构。因此，必须严格控制Wnt信号的正常形态发生。 Wnt/Beta-catenin活性由分泌的拮抗剂调节，并通过与Wnt配体，受体和共同因素的特定组合激活的替代β-Catenin独立途径的竞争。基于已发表的数据和我们的初步研究，我们假设Wnt10a及其相对WNT10B通过激活β-catenin信号传导促进牙齿发育和摩尔尖加形成，并与分泌的SOSTDC1，WIF1和DKK家族抑制剂与分泌的SOSTDC1，WIF1和DKK家族抑制剂竞争。我们进一步假设Wnt受体FZD2介导了Wnt5a的非典型信号传导，Wnt5a拮抗了β-catenin途径，并在牙齿生长和尖端形成中起关键作用。我们将使用功能和救援实验的遗传丧失和体外方法来检验这些假设。我们将进一步利用空间和时间控制的递送系统来确定是否可以使用重组Wnt10a和Wnt10b蛋白来促进，以及SOSTDC1，WIF1和DKK蛋白在3-D培养中抑制，生长和CUSP形成。这些实验的结果将提出针对定义大小和形状的生物工程牙齿的潜在策略，并处理影响牙齿发育的遗传条件。

项目成果

Ultrananocrystalline diamond tip integrated onto a heated atomic force microscope cantilever.

超纳米晶金刚石尖端集成到加热原子力显微镜悬臂上。

• DOI: 10.1088/0957-4484/23/49/495302
• 发表时间: 2012
• 期刊: Nanotechnology
• 影响因子: 3.5
• 作者: Kim,HoeJoon;Moldovan,Nicolaie;Felts,JonathanR;Somnath,Suhas;Dai,Zhenting;Jacobs,TevisDB;Carpick,RobertW;Carlisle,JohnA;King,WilliamP
• 通讯作者: King,WilliamP

Role of surface-bound intermediates in the oxygen-assisted synthesis of amides by metallic silver and gold.

表面结合中间体在金属银和金氧辅助合成酰胺中的作用。

• DOI: 10.1021/ja303178z
• 发表时间: 2012
• 期刊: Journal of the American Chemical Society
• 影响因子: 15
• 作者: Siler,CassandraGF;Xu,Bingjun;Madix,RobertJ;Friend,CynthiaM
• 通讯作者: Friend,CynthiaM