Tedder Mary E, Liao Jun, Weed Benjamin, Stabler Christopher, Zhang Henry, Simionescu Agneta, Simionescu Dan T
Department of Bioengineering, Clemson University, Clemson, South Carolina 29634, USA.
Tissue Eng Part A. 2009 Jun;15(6):1257-68. doi: 10.1089/ten.tea.2008.0263.
Scaffolds for heart valve tissue engineering must function immediately after implantation but also need to tolerate cell infiltration and gradual remodeling. We hypothesized that moderately cross-linked collagen scaffolds would fulfill these requirements. To test our hypothesis, scaffolds prepared from decellularized porcine pericardium were treated with penta-galloyl glucose (PGG), a collagen-binding polyphenol, and tested for biodegradation, biaxial mechanical properties, and in vivo biocompatibility. For controls, we used un-cross-linked scaffolds and glutaraldehyde-treated scaffolds. Results confirmed complete pericardium decellularization and the ability of scaffolds to encourage fibroblast chemotaxis and to aid in creation of anatomically correct valve-shaped constructs. Glutaraldehyde cross-linking fully stabilized collagen but did not allow for tissue remodeling and calcified when implanted subdermally in rats. PGG-treated collagen was initially resistant to collagenase and then degraded gradually, indicating partial stabilization. Moreover, PGG-treated pericardium exhibited excellent biaxial mechanical properties, did not calcify in vivo, and supported infiltration by host fibroblasts and subsequent matrix remodeling. In conclusion, PGG-treated acellular pericardium is a promising scaffold for heart valve tissue engineering.
心脏瓣膜组织工程支架在植入后必须立即发挥作用，同时还需要耐受细胞浸润和逐渐重塑。我们假设适度交联的胶原蛋白支架能够满足这些要求。为了验证我们的假设，用脱细胞猪心包制备的支架用五倍子酰葡萄糖（PGG，一种与胶原蛋白结合的多酚）进行处理，并测试其生物降解性、双轴力学性能和体内生物相容性。作为对照，我们使用了未交联的支架和戊二醛处理的支架。结果证实了心包完全脱细胞，以及支架促进成纤维细胞趋化和帮助创建解剖学上正确的瓣膜形状结构的能力。戊二醛交联使胶原蛋白完全稳定，但在大鼠皮下植入时不允许组织重塑且会钙化。PGG处理的胶原蛋白最初对胶原酶有抗性，然后逐渐降解，表明是部分稳定。此外，PGG处理的心包表现出优异的双轴力学性能，在体内不钙化，并支持宿主成纤维细胞浸润和随后的基质重塑。总之，PGG处理的脱细胞心包是心脏瓣膜组织工程的一种有前景的支架。
