Burg K J L, Delnomdedieu M, Beiler R J, Culberson C R, Greene K G, Halberstadt C R, Holder W D, Loebsack A B, Roland W D, Johnson G A
Department of Bioengineering, 501 Rhodes Engineering Research Center, Clemson University, South Carolina 29634-0905, USA.
J Biomed Mater Res. 2002 Sep 5;61(3):380-90. doi: 10.1002/jbm.10146.
Absorbable polymers are unique materials that find application as temporary scaffolds in tissue engineering. They are often extremely sensitive to histological processing and, for this reason, studying fragile, tissue-engineered constructs before implantation can be quite difficult. This research investigates the use of noninvasive imaging using magnetic resonance microscopy (MRM) as a tool to enhance the assessment of these cellular constructs. A series of cellular, polylactide constructs was developed and analyzed using a battery of tests, including MRM. Distribution of rat aortic smooth muscle cells within the scaffolds was compared as one example of a tissue engineering MRM application. Cells were loaded in varying amounts using static and dynamic methods. It was found that the cellular component was readily identified and the polymer microstructure readily assessed. Specifically, the MRM results showed a heterogeneous distribution of cells due to static loading and a homogenous distribution associated with dynamic loading, results that were not visible through biochemical tests, scanning electron microscopy, or histological evaluation independently. MRM also allowed differentiation between different levels of cellular loading. The current state of MRM is such that it is extremely useful in the refinement of polymer processing and cell seeding methods. This method has the potential, with technological advances, to be of future use in the characterization of cell-polymer interactions.
可吸收聚合物是一种独特的材料，在组织工程中可用作临时支架。它们通常对组织学处理极为敏感，因此，在植入前研究脆弱的组织工程构建体可能相当困难。本研究调查了使用磁共振显微镜（MRM）进行无创成像作为增强对这些细胞构建体评估的工具。开发了一系列细胞聚丙交酯构建体，并使用包括MRM在内的一系列测试进行分析。作为组织工程MRM应用的一个例子，比较了支架内大鼠主动脉平滑肌细胞的分布。使用静态和动态方法以不同数量加载细胞。结果发现，细胞成分易于识别，聚合物微观结构易于评估。具体而言，MRM结果显示，由于静态加载，细胞呈异质分布，而与动态加载相关的细胞呈均匀分布，这些结果通过生化测试、扫描电子显微镜或组织学评估单独均不可见。MRM还能够区分不同水平的细胞加载。MRM的当前状态使其在改进聚合物加工和细胞接种方法方面极为有用。随着技术进步，这种方法有可能在未来用于表征细胞 - 聚合物相互作用。
