Kasper F Kurtis, Young Simon, Tanahashi Kazuhiro, Barry Michael A, Tabata Yasuhiko, Jansen John A, Mikos Antonios G
Department of Bioengineering, Rice University, PO Box 1892, MS-142, Houston, Texas 77251-1892, USA.
J Biomed Mater Res A. 2006 Aug;78(2):335-42. doi: 10.1002/jbm.a.30698.
This research examines the bone formation response to release of plasmid DNA encoding human Bone Morphogenetic Protein-2 from hydrogel composites consisting of cationized gelatin microspheres (CGMS) embedded within a crosslinked oligo(poly(ethylene glycol) fumarate) (OPF) hydrogel network in a critical-sized rat cranial defect model after 30 days. Four composite groups were investigated: (1) composites with 10 microg DNA loaded into the CGMS phase, (2) composites with 10 microg DNA loaded into the OPF phase, (3) composites with 100 microg DNA loaded into the OPF phase, and (4) composites without DNA (material control). Light microscopy revealed no enhancement in bone formation for groups releasing plasmid DNA, relative to the material control group. Limited formation of new bone was observed from the defect margins and within the defect for some samples. The hydrogels swelled appreciably and fragmentation of the implants was noted to varying degrees among samples within groups, with a presence of inflammatory cells related to the degree of fragmentation. The lack of enhancement in bone formation indicates that the release of plasmid DNA from the composites was not sufficient to elicit a bone regeneration response.
本研究在大鼠颅骨临界尺寸缺损模型中，检测了30天后，由嵌入交联聚（乙二醇）富马酸酯（OPF）水凝胶网络中的阳离子化明胶微球（CGMS）组成的水凝胶复合材料释放编码人骨形态发生蛋白-2的质粒DNA后，骨形成的反应。研究了四个复合材料组：（1）将10微克DNA加载到CGMS相中的复合材料；（2）将10微克DNA加载到OPF相中的复合材料；（3）将100微克DNA加载到OPF相中的复合材料；（4）不含DNA的复合材料（材料对照）。光学显微镜显示，相对于材料对照组，释放质粒DNA的组骨形成没有增强。在一些样本中，从缺损边缘和缺损内部观察到有限的新骨形成。水凝胶明显膨胀，各组样本中植入物均有不同程度的破碎，且存在与破碎程度相关的炎性细胞。骨形成缺乏增强表明，复合材料中质粒DNA的释放不足以引发骨再生反应。
