Cranial Bone Repair with Adipose-Derived Stem Cells

用脂肪干细胞修复颅骨

• 批准号: 6653947
• 负责人: Roy Clinton Ogle
• 金额: $ 14.8万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-15 至 2005-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6653947
• 关键词: adipose tissue; bone development; bone regeneration; cell differentiation; clinical research; collagen; computed axial tomography; craniofacial; histology; human embryonic stem cell line; human tissue; immunocytochemistry; laboratory rat; oral facial restoration; osteoblasts; osteogenesis; polymerase chain reaction; stem cells; technology /technique development; telomerase; terminal nick end labeling; tissue /cell culture; tissue engineering; tissue support frame

DESCRIPTION (provided by applicant): The long-term goal of this proposal is to develop an effective therapy to repair bony defects in the craniofacial skeleton employing adult stem cells derived from adipose tissue. Reconstructive surgery for developmental anomalies, trauma and resection following tumor removal requires materials to replace or induce the regeneration of bone. Currently applied methods, such as use of autologous grafts and banked bone, are limited in efficacy and carry the risk of donor site morbidity and infection. Tissue engineering of replacement bone lacks the limitations of current approaches while offering distinct advantages. Adipose-derived adult stem cells (ADASC) are easily isolated and can be induced to differentiate ex vivo into a variety of neural and mesodermal cell lineages including osteoprogenitors. The central hypothesis of this study is that ADASCs can be maintained as replicating multipotent stem cells, which can be induced to differentiate into osteoblasts in vitro and, when delivered appropriately, will repair bony defects in vivo. Two Specific Aims are proposed to test the hypothesis: 1) to characterize and optimize the isolation, growth and differentiation of ADASCs in vitro; and 2) to test the capacity of human ADASCs to mediate repair of critical-sized bone defects in the skulls of athymic rats. In Aim 1 the clonal nature of the osteoprogenitor population within the total ADASC isolate and the timing of expression of bone specific genes will be determined. Using early and late markers of osteogenic differentiation, conditions for differentiation will be optimized and compared with primary human osteoblasts and osteoprogenitors derived from a human embryonic stem cell line. In Aim 2, ADASCs will be delivered in collagen sponges. Then de novo bone formation will be measured by three-dimensional reconstruction of computed tomography (3DCT) at intervals over the healing process to determine the optimal cell and passage number, stage of differentiation, and seeding density for bone repair. These studies should indicate the potential of the ADASC to contribute to bony tissue engineering and are a prerequisite to testing of the many tissue scaffold systems being developed and methods for using stem cells as gene delivery vehicles. The characterization studies may also provide the basis to use this stem cell system as a model for study of osteogenic differentiation.

描述（由申请人提供）：本提案的长期目标是开发一种有效的疗法，采用来自脂肪组织的成体干细胞修复颅面骨骼中的骨缺损。用于发育异常、创伤和肿瘤切除后的切除的重建手术需要替代或诱导骨再生的材料。目前应用的方法，如使用自体移植物和骨库，在疗效上是有限的，并带有供体部位发病和感染的风险。组织工程替代骨缺乏现有方法的局限性，同时提供了独特的优势。脂肪来源的成体干细胞（ADASC）容易分离，并且可以离体诱导分化为包括骨祖细胞在内的多种神经和中胚层细胞谱系。本研究的中心假设是ADASC可以维持为复制多能干细胞，其可以在体外诱导分化为成骨细胞，并且当适当递送时，将在体内修复骨缺损。提出了两个具体目的来检验该假设：1）表征和优化体外ADASC的分离、生长和分化; 2）测试人ADASC介导无胸腺大鼠颅骨中临界尺寸骨缺损修复的能力。在目标1中，将确定总ADASC分离物中骨祖细胞群体的克隆性质和骨特异性基因表达的时间。使用成骨分化的早期和晚期标志物，优化分化条件，并与来源于人胚胎干细胞系的原代人成骨细胞和骨祖细胞进行比较。在目标2中，ADASC将在胶原海绵中递送。然后，在愈合过程中每隔一段时间通过计算机断层扫描（3DCT）的三维重建测量从头骨形成，以确定骨修复的最佳细胞和传代次数、分化阶段和接种密度。这些研究应该表明ADASC有助于骨组织工程的潜力，并且是测试正在开发的许多组织支架系统和使用干细胞作为基因递送载体的方法的先决条件。这些特性的研究也可能为使用这种干细胞系统作为研究成骨分化的模型提供基础。