Regulation of Cranial Suture Development by TGF-B and FG

描述（由申请人提供）：颅缝早闭是人类的一个重要健康问题，但颅缝早闭的发病机制和机制仍未解决。临床和实验研究表明转化生长因子-α 1（TGF-beta1）和成纤维细胞生长因子-2与颅缝融合有关。有证据表明，一种或两种分子对缝线融合的影响可能会被骨形态发生蛋白拮抗剂noggin进一步改变。在许多人类颅缝早闭综合征中已经报道了FGF受体的功能突变的获得，其中大多数这些综合征涉及FGF受体2（FGFR 2）。然而，TGF-β 1和FGF-2在颅缝发育中的确切作用尚未得到解释。我们假设：1）在小鼠后额叶（PF）缝发育期间，TGF-β 1和FGF-2的生物活性改变调节了上覆颅缝的融合; 2）这些分子在小鼠融合的PF缝中的表达与患有先天性颅缝早闭的人类儿童的融合缝中的表达相似。FGFR 2和noggin的改变也可能有助于改变TGF-β 1和FGF-2的生物活性，并进一步调节缝线融合。具体目的是1）定量从体内和体外模型中收获的小鼠颅骨组织中TGF-β 1、FGF-2、FGFR 2和noggin的基因表达。此外，将使用ELISA在体外培养基中测量TGF-β 1、FDF-2和头蛋白的蛋白水平。2)从先天性颅缝早闭患者中获取这些相同的生长因子和受体，定量分析其基因表达。我们将从接受开颅手术的儿童的融合缝线和专利缝线中采集组织，作为颅缝早闭标准治疗的一部分。这些数据将用于帮助确定小鼠和人类颅缝系统之间的关系。3)通过调节目标1中所述的生长因子和受体的生物利用度，在体外调节小鼠模型中的颅缝融合。我们将添加每种分子的重组形式或这些分子的抗体，以诱导正常开放的矢状缝融合或阻断PF缝的正常融合。4)探讨质粒DNA体外转染小鼠颅骨组织的可能性。如果成功的话，基因操纵的目标生长因子和受体可能会被用来调节颅缝的发展在未来的研究。5)获得足够的分子生物学知识，发展成为独立的临床科学家。这一建议将提供机制的见解颅缝发育的调节，并有助于将小鼠和人类模型的颅缝早闭。

DESCRIPTION (provided by applicant): Craniosynostosis is a significant health issue in humans, yet the pathogenesis and the mechanism of craniosynostosis are still unsolved. Clinical and experimental studies have implicated Transforming Growth Factor-a 1 (TGF-beta1) and Fibroblast Growth Factor-2 in cranial suture fusion. There is evidence that the effect of one or both molecules on suture fusion may be further altered by noggin, a bone morphogenetic protein antagonist. Gain of function mutations in FGF receptors have been reported in numerous human craniosynostosis syndromes, with the majority of these syndromes implicating FGF receptors 2 (FGFR2). However, the precise role of TGF-beta1 and FGF-2 in cranial suture development has not been explained. We hypothesize that 1) during the period of posterior frontal (PF) suture development in the mouse, altered biologic activity of TGF-beta1 and FGF-2 regulates fusion of the overlying suture calvaria, and 2) expression of these molecules in the fused PF suture in mice parallels that in fused sutures from human children with congenital craniosynostosis. Alteration in FGFR2 and noggin may also contribute to alter biologic activity of TGF-Beta1 and FGF-2 and further regulate suture fusion. Specific aims are 1) To quantity gene expression of TGF-beta1, FGF-2, FGFR2, and noggin in mouse cranial tissues harvested from both in vivo and in vitro models. Additionally, protein levels of TGF- beta1, FDF-2, and noggin will be measured in culture media in vitro using ELISA. 2) To quantitate gene expression of these same growth factors and receptors harvested from human patients with cogenital craniosynostosis. We will harvest tissue from both a fused suture and a patent suture from children undergoing craniotomy as part of the standard treatment for craniosynotosis. These data will be used to help determine the relationship between the mouse and human cranial suture systems. 3) To modulate cranial suture fusion in the mouse model, in vitro by modulating the bioavailability of the growth factor and receptors described in Aim 1. We will add recombinant forms of each molecule or antibodies to these molecules to either induce fusion of the normally patent sagittal suture or block the normal fusion of the PF suture. 4) To investigate the possibility of in vitro plasmid DNA transfection of mouse cranial tissue. If successful, gene manipulation of the target growth factors and receptors may be used to regulate cranial suture development in future studies. 5) To gain adequate knowledge of molecular biology to develop into an independent clinician-scientist. This proposal will provide mechanistic insights into the regulation of cranial suture development, and help to relate mouse and human models of craniosynostosis.