Tissue Engineering a Suture Replacement for Children with Craniosynostosis

描述(由申请人提供)： 颅缝融合是指一条或多条颅缝过早融合。目前的治疗包括广泛的手术干预，包括额眶推进和根治性颅骨重新定位。虽然目前的技术通常成功地恢复了正常的脑生长向量，增加了颅内体积，降低了颅内压，但手术干预范围广泛，结果参差不齐。此外，颅骨再生速度很快，手术后不久就会拒绝。当输血发生时，需要进行二次手术，这会增加患者的发病率和死亡率。我们小组已经着手从根本上改进颅缝早闭的治疗，通过最小化手术干预的程度，改善结果，并抑制再融合的发生。我们处于一个独特的位置，可以设计一种新的疗法，这种疗法可以量身定做，以改善患有颅缝早闭的儿童的治疗，而不考虑分子或遗传病因。为了确定适当的生长因子信号、剂量和细胞比例，我们将使用一种新的喷墨打印技术来鉴定干细胞，以评估从人类非综合征冠状缝合融合的兔模型中分离出的骨骼肌源性和脂肪源性细胞的成骨潜力(目标#1A)。基于我们在Aim#1A中的发现，我们将使用我们的喷墨打印技术创建一种缝合替换支架，以创建空间定义的固定化生长因子图案，该图案将在体外重复形成由交错的非骨区分隔的两个骨区域(Aim#1B)。然后，我们将测试我们的缝合替换支架的有效性，以改进体内颅缝融合兔的手术治疗(目标2)。为了证明这种方法在人类中的临床相关性，我们将在颅缝融合儿童的骨骼肌和脂肪来源的细胞上使用类似于Aim#1中的祖细胞特征，并在体外评估这些细胞对我们的缝合替换支架的响应(Aim#3)。通过完成这些目标，我们将在改进颅缝融合症的手术治疗方面取得重大进展。此外，可用于表征干细胞分化潜力和空间控制多潜能细胞分化的技术的发展将在组织工程领域产生广泛影响。 公共卫生相关声明(由申请人提供)：项目叙述性颅骨融合症是指一个或多个颅骨缝过早融合的术语。缝合线的融合是由于骨和非骨组织之间的正确图案形成失败造成的。我们已经着手通过组织工程学来改善儿童颅缝早闭的外科治疗。我们将开发紧急喷墨打印技术来表征祖细胞，并在体内复制组织形成的图案。通过构图细胞分化，有可能创造出功能类似于正常未融合缝合线的组织。在执行拟议工作中开发的技术将对干细胞生物学领域、组织工程学的应用以及儿童颅缝融合症的治疗产生广泛影响。

DESCRIPTION (provided by applicant): Craniosynostosis is defined as the premature fusion of one or more of the cranial sutures. Current therapy involves extensive surgical intervention including fronto-orbital advancement and radical calvarial bone repositioning. Although the current techniques often successfully restore normal brain growth vectors, increase intracranial volume, and decrease intracranial pressure, the surgical intervention is extensive and the outcomes are variable. Furthermore, the calvarial bone regenerates quickly and can refuse shortly after surgery. When refusion occurs, secondary surgeries are required which increases patient morbidity and mortality. Our group has set out to radically improve the treatment of craniosynostosis by minimizing the extent of surgical intervention, improving outcomes, and inhibiting the occurrence of refusion. We are in a unique position to design a novel therapy that could be tailored to improve the treatment of children who present with craniosynostosis, regardless of the molecular or genetic etiology. To determine the proper growth factor cues, doses, and cell fraction, we will employ stem cell characterization using a novel inkjet printing technology to assess the osteogenic potential of skeletal muscle-derived and adipose-derived cells isolated from a rabbit model of human nonsyndromic coronal suture synostosis (Aim #1A). Based on our findings from Aim #1A, we will create a suture replacement scaffold using our inkjet printing to create spatially-defined patterns of immobilized growth factors that will reproducibly form two regions of bone separated by an interdigitating non- bone region in vitro (Aim #1B). We will then test the effectiveness of our suture replacement scaffolds to improve the surgical treatment of rabbits with craniosynostosis in vivo (Aim #2). To demonstrate the clinical relevance of this approach in humans, we will employ similar progenitor cell characterization as in Aim #1 on cells derived from skeletal muscle and adipose of children with craniosynostosis and assess these cells' responsiveness to our suture replacement scaffolds in vitro (Aim #3). By completing these Aims, we will make significant progress in improving the surgical treatment of craniosynostosis. Furthermore, the development of technologies that can be used to both characterize stem cell differentiation potential and to spatially control the differentiation of multipotent cells will have broad impact in the field of tissue engineering. Public Health Relevance Statement (Provided by Applicant): Project Narrative Craniosynostosis is the term given to the premature fusion of one or more of the calvarial sutures. Fusion of a suture results from a failure of correct pattern formation between bone and non-bone tissues. We have set out to improve the surgical management of children with craniosynostosis through tissue engineering. We will develop emergent inkjet printing technology to characterize progenitor cells and to reproducibly pattern tissue formation in vivo. By patterning cell differentiation, it may be possible to create tissues that function similarly to normal, unfused sutures. The technology that will be developed in performing the proposed work will have broad impact on the field of stem cell biology, the application of tissue engineering, and on the treatment of children with craniosynostosis.