Tufts University, Department of Biomedical Engineering, MA 02155, USA.
Biomaterials. 2012 Feb;33(4):1017-23. doi: 10.1016/j.biomaterials.2011.10.063. Epub 2011 Nov 9.
Silk has traditionally been used for surgical sutures due to its lasting strength and durability; however, the use of purified silk proteins as a scaffold material for vascular tissue engineering goes beyond traditional use and requires application-orientated biocompatibility testing. For this study, a library of Bombyx mori silk films was generated and exposed to various solvents and treatment conditions to reflect current silk processing techniques. The films, along with clinically relevant reference materials, were exposed to human whole blood to determine silk blood compatibility. All substrates showed an initial inflammatory response comparable to polylactide-co-glycolide (PLGA), and a low to moderate haemostasis response similar to polytetrafluoroethylene (PTFE) substrates. In particular, samples that were water annealed at 25 °C for 6 h demonstrated the best blood compatibility based on haemostasis parameters (e.g. platelet decay, thrombin-antithrombin complex, platelet factor 4, granulocytes-platelet conjugates) and inflammatory parameters (e.g. C3b, C5a, CD11b, surface-associated leukocytes). Multiple factors such as treatment temperature and solvent influenced the biological response, though no single physical parameter such as β-sheet content, isoelectric point or contact angle accurately predicted blood compatibility. These findings, when combined with prior in vivo data on silk, support a viable future for silk-based vascular grafts.
丝绸由于其持久的强度和耐用性，传统上被用于手术缝线;然而，将纯化的丝蛋白作为血管组织工程的支架材料的使用超出了传统用途，需要面向应用的生物相容性测试。在这项研究中，生成了一个家蚕丝膜文库，并将其暴露于各种溶剂和处理条件下，以反映当前的丝绸加工技术。将这些薄膜与临床相关的参考材料一起暴露于人全血中，以确定丝绸的血液相容性。所有的基底材料都显示出与聚乳酸-共-乙醇酸（PLGA）相当的初始炎症反应，以及与聚四氟乙烯（PTFE）基底相似的低到中度止血反应。特别是在 25°C 下用水退火 6 小时的样品，根据止血参数（如血小板衰减、凝血酶-抗凝血酶复合物、血小板因子 4、粒细胞-血小板结合物）和炎症参数（如 C3b、C5a、CD11b、表面相关白细胞）显示出最佳的血液相容性。许多因素，如处理温度和溶剂，影响着生物反应，尽管没有单一的物理参数，如β-折叠含量、等电点或接触角，能准确预测血液相容性。这些发现，结合之前关于丝素的体内数据，为基于丝素的血管移植物的未来提供了支持。
