载β-TC3细胞新型葡萄糖敏感微囊的生物学性能

Biological characteristics of glucose-responsive microcapsules carrying beta-TC3 cells

背景:构建一种能够感应外界葡萄糖浓度变化而控制胰岛素释放的系统对有效地控制糖尿病的发生与发展具有重要意义。目的:研究负载β-TC3细胞的葡萄糖敏感海藻酸钠/改性壳聚糖/海藻酸钠微囊的性能。方法:通过层层自组装方法制备葡萄糖敏感海藻酸钠/改性壳聚糖/海藻酸钠微囊,观察并评价其性能;进一步应用制备的葡萄糖敏感微囊包裹β-TC3细胞,观察微囊内细胞的增殖情况。结果与结论:实验制备的葡萄糖敏感海藻酸钠/改性壳聚糖/海藻酸钠微囊温水浴振荡48h后完整微囊仍达到95%,且微囊硬度变小、弹性增大;通透性测试结果显示实验制备的微囊可将大分子物质牛血清白蛋白、免疫球蛋白G截留在微囊外;体外释放实验显示,随着周围环境葡萄糖缓冲液浓度的增加,微囊内胰岛素释药量增大。说明实验制备的葡萄糖敏感海藻酸钠/改性壳聚糖/海藻酸钠微囊具有良好的机械强度、葡萄糖敏感特性与免疫隔离功能。进一步将β-TC3细胞微囊化,发现β-TC3细胞在微囊中生长良好,增殖高峰滞后于未微囊化的细胞。可见该生物微囊具有良好的细胞相容性。

BACKGROUND：To prepare glucose-responsive microcapsules which can control insulin release as changing the glucose concentration in the medium is of great significance to control the occurrence and development of diabetes mel itus. OBJECTIVE：To study the performance of glucose-responsive alginate/modified-chitosan/alginate microcapsules carryingβ-TC3 cells. METHODS：Glucose-responsive alginate/modified-chitosan/alginate microcapsules were prepared by layer-by-layer self-assembly method to evaluate the performance. And the glucose-responsive microcapsules carryingβ-TC3 cells were prepared to observe the cel proliferation within the microcapsules. RESULTS AND CONCLUSION：The integrity rate of glucose-responsive alginate/modified-chitosan/alginate microcapsules could be 95%after 48 hours oscil ation, and the hardness of microcapsules lowered, but the elasticity increased. The permeability test showed that microcapsules intercepted macromolecular substances such as bovine serum albumin and immuno-globulin G. The microcapsules could release more insulin with the increase of glucose concentration. As described above, the glucose-responsive alginate/modified-chitosan/alginate microcapsules had good mechanical strength, immunoisolation effect and glucose sensitivity. Theβ-TC3 cells entrapped in the glucose-responsive microcapsules could grow wel and the peak of cel proliferation lagged behind as compared with non-microencapsulated cells, indicating the glucose-responsive microcapsules had good biocompatibility.