Tan Qiang, Steiner Rudolf, Yang Lin, Welti Manfred, Neuenschwander Peter, Hillinger Sven, Weder Walter
Division of Thoracic Surgery, University Hospital, CH-8091 Zurich, Switzerland.
Eur J Cardiothorac Surg. 2007 May;31(5):806-11. doi: 10.1016/j.ejcts.2007.01.045. Epub 2007 Feb 22.
To test the effects of a continuous medium flow inside DegraPol scaffolds on the reepithelialization and revascularization processes of a tissue-engineered trachea prosthesis.
In this proof-of-principle study a continuous medium flow was maintained within a tubular DegraPol scaffold by an inserted porous catheter connected to a pump system. The impact of the intra-scaffold medium flow on the survival of a tracheal epithelial sheet wrapped around and on chondrocyte delivery to the DegraPol scaffold was studied. In the chick embryo, chorioallantoic membrane (CAM) model angiogenesis within the biomaterial was investigated.
Scanning electronic microscopy (SEM) images showed an intact epithelial layer after a 2-week support by continuous medium flow underneath. On histology, three-dimensional cell growth was detected in the continuous delivery group. The CAM assay showed that angiogenesis was enhanced within the DegraPol scaffolds when vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) was added to the perfusate.
Taken together, these results demonstrated that the built-in perfusion system within DegraPol scaffolds was able to maintain an intact tracheal epithelial layer, allowed a continuous delivery of cells, and kept an efficient VEGF/VPF expression level which accelerated angiogenic response in the CAM assay. This design combines the in vitro and in vivo parts of tissue engineering and offers the possibility to be used as an in vivo bioreactor implanted for the tissue-engineered reconstruction of trachea and of other organs.
测试DegraPol支架内持续的介质流动对组织工程气管假体再上皮化和血管再生过程的影响。
在这项原理验证研究中，通过连接到泵系统的插入式多孔导管在管状DegraPol支架内维持持续的介质流动。研究了支架内介质流动对包裹在其周围的气管上皮片存活以及软骨细胞输送到DegraPol支架的影响。在鸡胚中，研究了生物材料内的绒毛尿囊膜（CAM）模型血管生成。
扫描电子显微镜（SEM）图像显示，在下方持续的介质流动支持2周后上皮层完整。组织学检查显示，连续递送组中检测到三维细胞生长。CAM试验表明，当向灌注液中添加血管内皮生长因子/血管通透性因子（VEGF/VPF）时，DegraPol支架内的血管生成增强。
综上所述，这些结果表明DegraPol支架内的内置灌注系统能够维持完整的气管上皮层，允许细胞持续递送，并保持有效的VEGF/VPF表达水平，从而在CAM试验中加速血管生成反应。这种设计结合了组织工程的体外和体内部分，并提供了用作体内生物反应器的可能性，用于气管和其他器官的组织工程重建。
