Pham Quynh P, Kasper F Kurtis, Mistry Amit S, Sharma Upma, Yasko Alan W, Jansen John A, Mikos Antonios G
Department of Bioengineering, Rice University, Houston, Texas 77251-1892, USA.
J Biomed Mater Res A. 2009 Feb;88(2):295-303. doi: 10.1002/jbm.a.31875.
In this study, the osteoinductive potential of an in vitro generated extracellular matrix (ECM) deposited by marrow stromal cells seeded onto titanium fiber mesh scaffolds and cultured in a flow perfusion bioreactor was investigated. Culture periods of 8, 12, and 16 days were selected to allow for different amounts of ECM deposition by the cells as well as ECM with varying degrees of maturity (Ti/ECM/d8, Ti/ECM/d12, and Ti/ECM/d16, respectively). These ECM-containing constructs were implanted intramuscularly in a rat animal model. After 56 days, histologic analysis of retrieved constructs revealed no bone formation in any of the implants. Surrounding many of the implants was a fibrous capsule, which was often interspersed with fat cells. Within the pore spaces, the predominant tissue response was the presence of blood vessels and young fibroblasts or fat cells. The number of blood vessels on a per area basis calculated from a histomorphometric analysis increased as a function of the amount of ECM within the implanted constructs, with a significant difference between Ti/ECM/d16 and plain Ti constructs. These results indicate that although an in vitro generated ECM alone may not induce bone formation at an ectopic site, its use may enhance the vascularization of implanted constructs.
在本研究中，研究了接种于钛纤维网支架上并在流动灌注生物反应器中培养的骨髓基质细胞所产生的体外细胞外基质（ECM）的骨诱导潜力。选择8天、12天和16天的培养期，以使细胞沉积不同量的ECM以及具有不同成熟度的ECM（分别为Ti/ECM/d8、Ti/ECM/d12和Ti/ECM/d16）。将这些含ECM的构建体肌肉内植入大鼠动物模型。56天后，对取出的构建体进行组织学分析，结果显示所有植入物中均未形成骨。许多植入物周围是一个纤维囊，其中常常散布着脂肪细胞。在孔隙空间内，主要的组织反应是存在血管以及年轻的成纤维细胞或脂肪细胞。通过组织形态计量分析计算得出的每单位面积血管数量随植入构建体中ECM量的增加而增加，Ti/ECM/d16构建体与普通钛构建体之间存在显著差异。这些结果表明，尽管单独的体外生成的ECM可能不会在异位部位诱导骨形成，但其使用可能会增强植入构建体的血管化。
