CSF-1 in Dental Biology

CSF-1 在牙科生物学中的应用

• 批准号: 6866421
• 负责人: SHERRY L ABBOUD-WERNER
• 金额: $ 27.74万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-03-05 至 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6866421
• 关键词: antisense nucleic acid; colony stimulating factor; dental development; dentin; developmental genetics; flow cytometry; gene expression; gene targeting; gene therapy; genetically modified animals; immunocytochemistry; in situ hybridization; laboratory mouse; messenger RNA; osteocalcin; polymerase chain reaction; protein deficiency; protein isoforms; protein structure function; recombinant virus; scanning electron microscopy; tooth enamel; transfection /expression vector

DESCRIPTION: Tooth matrix proteins are tightly regulated and critical for matrix deposition, mineralization and maturation. Altered expression of these proteins leads to enamel and/or dentin defects. We have made the novel observation that macrophage colony stimulating factor (CSF-1), a factor essential for osteoclast-mediated tooth eruption, is also required for normal tooth matrix formation. In op/op mice, a thymidine insertion in the coding sequence of the CSF-1 gene results in a deficiency of both the soluble (s)and membrane bound (m) forms of CSF-1 that decreases osteoclasts and leads to osteopetrosis and failure of tooth eruption. Analysis ofop/op teeth show a combined enamel and dentin defect characterized by thin, poorly organized enamel and dentin dysplasia that was associated with aberrant expression of tooth matrix proteins. Transgenic op/op mice harboring either the sCSF-1 or mCSF-1 cDNAs under the control of the osteocalcin promoter have also been generated and show distinct tooth phenotypes. Expression of sCSF-1 almost corrected the dental defects in op/op mice, while mCSF-1 partially corrected the enamel defect and resulted in an amelogenesis imperfecta phenotype. The long-term goal of this proposal is to determine the role of CSF-1 in primary tooth formation and the mechanisms that mediate the differential effects of CSF-1 isoforms on tooth matrix formation. Our first hypothesis is that CSF-1 is required for normal tooth matrix protein expression and that CSF-1 deficiency causes aberrant expression of these proteins that leads to specific dental defects during development. To address this issue, the expression profile of tooth matrix proteins, histologic features, mineralization and structural integrity by SEM ofop/op teeth will be compared to that of wt during embryonic and postnatal growth. Analysis of the endogenous developmental pattern of sCSF- 1 and mCSF- 1 expression in wt mice using in situ hybridization will be performed to elucidate the potential role of these isoforms in regulating tooth matrix proteins. Our second hypothesis is that sCSF-1 and mCSF-1 differentially regulate tooth matrix protein expression that, in turn, mediate the distinct biologic effects of these isoforms on tooth matrix formation. For these experiments, the patterns of matrix protein expression, mineralization and structural integrity during development will be analyzed in parallel in op/op mice expressing either sCSF-1 or mCSF-1 and correlated with rescue of the tooth phenotype in these mice. We will also test the hypothesis that adenoviral-mediated gene targeting of sCSF-1 to teeth will ameliorate the dental defects in op/op and, perhaps, rescue the enamel defect in mCSF-l-expressing op/op mice. These studies should increase our understanding of the molecular mechanisms involved in sCSF-1 and mCSF-l-mediated tooth matrix formation and may suggest novel therapeutic strategies designed to restore enamel and dentin tissues in a variety of dental disorders including amelogenesis imperfect a and dentinogenesis imperfecta.

描述：牙齿基质蛋白受到严格调控，对基质沉积、矿化和成熟至关重要。这些蛋白表达的改变导致牙釉质和/或牙本质缺陷。我们发现巨噬细胞集落刺激因子（CSF-1）是破骨细胞介导的牙萌出的重要因子，也是正常牙基质形成所必需的。在op/op小鼠中，在CSF-1基因编码序列中插入胸腺嘧啶导致可溶性(s)和膜结合(m)形式的CSF-1缺乏，从而减少破骨细胞并导致骨质疏松和牙出牙失败。对op/op牙齿的分析显示牙釉质和牙本质的结合缺陷，其特征是牙釉质薄，组织不良和牙本质发育不良，与牙基质蛋白的异常表达有关。在骨钙素启动子的控制下，也产生了含有sCSF-1或mCSF-1 cdna的转基因op/op小鼠，并显示出不同的牙齿表型。sCSF-1的表达几乎纠正了op/op小鼠的牙缺陷，而mCSF-1的表达部分纠正了牙釉质缺陷，导致无釉发育不完全表型。本研究的长期目标是确定CSF-1在乳牙形成中的作用，以及介导CSF-1同种异构体对牙基质形成差异影响的机制。我们的第一个假设是，正常的牙基质蛋白表达需要CSF-1，而缺乏CSF-1会导致这些蛋白的异常表达，从而导致发育过程中特定的牙齿缺陷。为了解决这个问题，我们将通过扫描电镜比较op/op牙齿在胚胎和出生后生长期间的牙基质蛋白表达谱、组织学特征、矿化和结构完整性。利用原位杂交技术分析小鼠体内sCSF- 1和mCSF- 1表达的内源性发育模式，以阐明这些异构体在调节牙齿基质蛋白中的潜在作用。我们的第二个假设是，sCSF-1和mCSF-1调节牙齿基质蛋白表达的差异，进而介导这些同种异构体对牙齿基质形成的不同生物学效应。在这些实验中，将并行分析表达sCSF-1或mCSF-1的op/op小鼠发育过程中基质蛋白表达、矿化和结构完整性的模式，并与这些小鼠的牙齿表型修复相关。我们还将验证腺病毒介导的sCSF-1基因靶向牙齿的假设，该假设将改善op/op的牙缺陷，并可能挽救表达mcsf -1的op/op小鼠的牙釉质缺陷。这些研究将增加我们对sCSF-1和mcsf -1介导的牙基质形成的分子机制的理解，并可能提出新的治疗策略，用于修复各种牙齿疾病（包括无淀粉性不完全性和牙本质不完全性）的牙釉质和牙本质组织。