【摘要】 背景:前期研究制备了不同混合比例的丝素蛋白/聚乳酸复合材料,经全身过敏反应、急性毒性、溶血、热源及细胞共培养实验证实其具有良好的组织工程材料性能。目的:考察不同混合比例丝素蛋白/聚乳酸复合材料在小鼠皮下的降解情况。方法:在54只ICR小白鼠脊柱两侧分别制作皮下囊状间隙,随机分为3组,分别植入丝素蛋白与聚乳酸质量比为30∶70、40∶60、50∶50的丝素蛋白/聚乳酸复合材料,植入后1,3,9周取植入处组织,进行组织病理切片苏木精-伊红染色、Masson染色和CD34免疫组织化学染色。结果与结论:①苏木精-伊红染色:植入后9周,3组新生血管逐渐成熟并可见成纤维细胞长入,材料结构崩解现象较明显,组织细胞进一步长入材料,其中50∶50复合材料组与40∶60复合材料组材料降解较快;②Masson染色:植入后9周,3组均可见到成熟血管及较多胶原纤维长入材料,40∶60复合材料组、50∶50复合材料组较30∶70复合材料组血管和胶原纤维长入明显,50∶50复合材料组植入后不同时间点的胶原纤维表达量高于其余两组(P<0.05);③CD34免疫组织化学染色:3组材料植入后1-3周的CD34阳性表达逐渐增加,9周后材料周围CD34阳性表达下降,50∶50复合材料组植入后不同时间点的CD34阳性表达高于其余两组(P<0.05);④结果表明:丝素蛋白与聚乳酸质量比为50∶50的丝素蛋白/聚乳酸复合材料在小白鼠体内降解更快。更多还原

【Abstract】 BACKGROUND: In our previous study, we prepared some silk fibroin/polyactic acid composite materials at different proportions, which are verified as tissue-engineered materials with good performance by systemic hypersensitivity test, acute toxicity test, hemolysis test, pyrogenic test, and cell co-culture experiment. OBJECTIVE: To study the subcutaneous degradation of silk fibroin/polylactic acid composite materials at different proportions in mice. METHODS: Fifty-four ICR mice were subjected to subcutaneous cystic clearance on the both sides of the spine, and then randomized into three groups. The silk fibroin/polylactic acid composites at 40:60, 50:50, and 30:70 were implanted into the cystic space, respectively. The specimens were taken out at 1, 3, 9 weeks after implantation. Histopathological staining, Masson staining, and CD34 immunohistochemical staining were performed. RESULTS AND CONCLUSION:(1) Hematoxylin-eosin staining: At 9 weeks after implantation, new blood vessels gradually formed and visible fibroblasts gradually grew into the composites in the three groups. Structural collapse of the materials became more apparent, and tissues and cells further grew into the materials. The 40:60 and 50:50 composites were degraded more quickly than the other one.(3) Masson staining: At 9 weeks after implantation, mature blood vessels and collagen fibers were detectable in the three groups, which were more apparent in the 40:60 and 50:50 groups than the 30:70 group. The collagen fiber expression in the 50:50 group was significantly higher than that in the other two groups at different time after implantation(P < 0.05).(3) CD34 immunohistochemical staining: At 1-3 weeks after implantation, CD34 positive expression gradually increased in the three groups. After 9 weeks, the CD34 expression decreased in the three groups; however, the CD34 positive expression in the 50:50 group was significantly higher than that in the other two groups at different time after implantation(P < 0.05). To conclude, the silk fibroin/polylactic acid composite material at a proportion of 50:50 was degraded more quickly in mice.更多还原