Runx2/Cbfa1-genetically engineered skeletal myoblasts mineralize collagen scaffolds in vitro
Runx2/Cbfa1-genetically engineered skeletal myoblasts mineralize collagen scaffolds in vitro
复制标题
DOI：
10.1002/bit.20251
复制
发表时间：
2004-11-05
影响因子：
3.8
通讯作者：
García, AJ
中科院分区：
文献类型：
--
作者：
Gersbach, CA;Byers, BA;García, AJ
祖细胞和干细胞的基因工程是解决与组织工程应用相关的细胞来源限制的一种有吸引力的方法。骨组织工程是修复大型骨缺损的一种很有前途的策略，但在一定程度上受到持续的矿化细胞来源的可用性的限制。本研究检测了通过基因工程过度表达Runx2/Cbfa1的原代骨骼肌母细胞的体外矿化潜力，Runx2/Cbfa1是骨形成所必需的成骨细胞转录调节因子。这些细胞在3D纤维胶原支架周围静态培养6周后存活。与对照组相比，外源性Runx2表达诱导成骨分化并抑制肌生成。通过显微计算机断层扫描、组织学分析和傅里叶变换红外光谱检测，runx2修饰的细胞沉积了大量矿化基质和羟基磷灰石，而对照组细胞植入的支架则没有矿化区域。虽然runx2工程细胞的矿化仅限于构建物的外围，但与细胞活力共定位，足以使构建物的压缩模量相对于对照组增加30倍。这项工作表明，Runx2在骨骼肌母细胞中的过表达可能通过为体外矿化和构建成熟提供有效的细胞来源来解决当前骨组织工程的障碍。此外，与可溶性信号分子相比，利用基因工程方法表达下游控制因子和转录调节因子，代表了一种增强组织工程应用中细胞活性的强大策略。(C) 2004 Wiley期刊有限公司
Genetic engineering of progenitor and stem cells is an attractive approach to address cell sourcing limitations associated with tissue engineering applications. Bone tissue engineering represents a promising strategy to repair large bone defects, but has been limited in part by the availability of a sustained, mineralizing cell source. This study examined the in vitro mineralization potential of primary skeletal myoblasts genetically engineered to over-express Runx2/Cbfa1, an osteoblastic transcriptional regulator essential to bone formation. These cells were viable at the periphery of 3D fibrous collagen scaffolds for 6 weeks of static culture. Exogenous Runx2 expression induced osteogenic differentiation and repressed myogenesis in these constructs relative to controls. Runx2-modified cells deposited significant amounts of mineralized matrix and hydroxyapatite, as determined by microcomputed tomography, histological analysis, and Fourier transform infrared spectroscopy, whereas scaffolds seeded with control cells exhibited no mineralized regions. Although mineralization by Runx2-engineered cells was confined to the periphery of the construct, colocalizing with cell viability, it was sufficient to increase the compressive modulus of constructs 30-fold relative to controls. This work demonstrates that Runx2 overexpression in skeletal myoblasts may address current obstacles of bone tissue engineering by providing a potent cell source for in vitro mineralization and construct maturation. Additionally, the use of genetic engineering methods to express downstream control factors and transcriptional regulators, in contrast to soluble signaling molecules, represents a robust strategy to enhance cellular activities for tissue engineering applications. (C) 2004 Wiley Periodicals, Inc.