CELLULAR BASIS OF TOOTH ERUPTION

牙齿萌出的细胞基础

• 批准号: 3222732
• 负责人: GARY E WISE
• 金额: $ 10.83万
• 依托单位: UNIVERSITY OF NORTH TEXAS HLTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-07-01 至 1994-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3222732
• 关键词: SDS polyacrylamide gel electrophoresis; acid phosphatase; affinity chromatography; biochemistry; cell growth regulation; dental development; electron microscopy; enamel organ; epidermal growth factor; extracellular matrix; extracellular matrix proteins; fibroblasts; growth factor receptors; immunocytochemistry; immunofluorescence technique; laboratory rat; molecular biology; monocyte; osteoclasts; protein biosynthesis; scanning electron microscopy; tissue /cell culture; transforming growth factors; western blottings

The long-term objective of this proposal is to determine how the cells of the dental follicle and stellate reticulum (SR) may regulate tooth eruption. Previous studies have shown that the dental follicle (DF), a loose connective tissue sac surrounding the developing tooth, is necessary for tooth eruption - possibly by regulating concurrent events of tooth eruption; namely, bone resorption, bone formation and tooth movement. My laboratory has shown that there is an influx of mononuclear cells (monocytes?) into the DF prior to tooth eruption and they may be precursors of osteoclasts that are necessary to erode the bony crypt in order fro eruption to occur. In conjunction with this, changes occur in the extracellular matrix content of the DF prior to eruption. Hence, it is the hypothesis of this proposal that the initiation and regulation of the cellular/extracellular events of tooth eruption are controlled by growth factors, primarily epidermal growth factor (EGF) and transforming growth factor-beta 1 (TGF-beta1). Thus, this study first will use light and EM immunocytochemical techniques to determine the spatial and temporal localization of EGF and TGF-beta1 in the DF and SR, as well as using a monoclonal antibody to the EGF receptor to determine its localization. Next, the factors will be injected into rats to determine their effects on the DF in terms of monocyte influx and extracellular matrix changes. This effect on rate of tooth eruption also will be assessed and correlated with any cellular/extracellular changes in the DF. To determine if the growth factors act indirectly by stimulating cells of the DF or SR to secrete a protein, a pure population of cultured DF cells or another population of cultured SR cells will be incubated with the growth factors. The serum - free medium will then be assayed to determine if new proteins are secreted by the cells or if there is an increase in amount of a given protein normally secreted by the cells. If a new protein is secreted, it will be purified and injected in rats to determine its effects on rates of tooth eruption and on cellular events in the DF. Elucidating the cell and molecular basis of tooth eruption could lead to methods for facilitating the eruption of impacted teeth, or prevent loss of deciduous teeth if there were no permanent successors. Equally attractive, new techniques might be developed in orthodontics once a cellular understanding of tooth eruption is obtained.

该提案的长期目标是确定细胞如何 牙囊和星状网（SR）的结构可以调节牙齿 爆发。 先前的研究表明，牙囊（DF）是 正在发育的牙齿周围有松散的结缔组织囊， 牙齿萌出所必需的 - 可能通过调节并发事件 牙齿萌出；即骨吸收、骨形成和牙齿 移动。 我的实验室表明，有大量的涌入 在牙齿萌出之前将单核细胞（单核细胞？）注入 DF 中，并且 它们可能是破骨细胞的前体，是侵蚀骨细胞所必需的。 骨隐窝，以便发生萌发。 与此相结合， DF 的细胞外基质含量发生变化之前 爆发。 因此，本提案的假设是 牙齿细胞/细胞外事件的启动和调节 出疹由生长因子控制，主要是表皮生长 因子（EGF）和转化生长因子-β1（TGF-β1）。 因此， 这项研究首先将使用光和 EM 免疫细胞化学技术 确定 EGF 和 TGF-β1 的空间和时间定位 DF 和 SR，以及使用 EGF 单克隆抗体 受体来确定其定位。 接下来，因素将是 注射到大鼠体内以确定其对 DF 的影响 单核细胞流入和细胞外基质变化。 这对速率的影响 牙齿萌出的情况也将被评估并与任何 DF 中的细胞/细胞外变化。 判断是否增长 因子通过刺激 DF 或 SR 细胞分泌 蛋白质、培养的 DF 细胞的纯群体或另一群体 培养的 SR 细胞将与生长因子一起孵育。 这 然后对无血清培养基进行分析以确定是否有新的蛋白质 由细胞分泌，或者如果a的量增加 给予细胞通常分泌的蛋白质。 如果有一种新的蛋白质 分泌后，将其纯化并注射到大鼠体内以确定其 对牙齿萌出率和 DF 细胞事件的影响。 阐明牙齿萌出的细胞和分子基础可能会导致 促进阻生牙萌出或防止脱落的方法 如果没有恒牙继承者，就会出现乳牙。 同样 一旦牙齿矫正可能会开发出有吸引力的新技术 获得了对牙齿萌出的细胞理解。