微囊化大鼠胰岛细胞的冷冻保存

Cryopreservation of micoencapsulated rat islets

目的探讨海藻酸钠-聚赖氨酸-海藻酸微囊在胰岛细胞冷冻保存过程中的作用。方法将分离纯化后的大鼠胰岛细胞分为微囊化组和游离组。经冷冻保存1月后在RPMI 1640中培养过夜,分别测定两组的胰岛细胞回收率、胰岛细胞直径并进行胰岛素刺激释放试验。结果微囊组胰岛细胞回收率为98．2％±1．4％,较游离组71．6％±2．9％显著提高 (P<0．05)。在高糖(16．7 mmol／L)刺激下,微囊组胰岛素分泌量较游离组高(22．6±1．8 mU/Lvs 11．7±1．5 mU/L,P<0．05)。在含有茶碱的高糖溶液中,微囊组的刺激指数为游离组的3倍。结论海藻酸钠-聚赖氨酸-海藻酸微囊可显著提高胰岛细胞冷冻保存后的回收率,并改善胰岛细胞的功能。

Objective To investigate the role of alginate-polylysine-alginate （APA） microcapsules in protecting rat islet cells in cryopreservation. Method Purified rat islet cells microencapsulated with APA and free islet cells were cryopreserved for one month and then thawed for culture in RPMI 1640 overnight. The morphology of the cells was observed and their function assessed by stimulated insulin release test. Result APA microcapsulation protected the fragile islets from freezing damage by increasing the recovery rate of the cells from 68.6%±2.9% to 94.7%±1.4% （P〈0.05）. After incubation with high glucose （16.7 mmol/L） solution, the insulin release from the encapsulated cells after cryopreservation significantly increased in comparison with that of the nonencapsulated cells （22.6±1.8 mU/L vs 11.7±1.5 mU/L, P〈0.05）. In high glucose solution containing theophylline, the calculated stimulation index of the encapsulated cells was about 3 times that of the nonencapsulated cells. Condusion APA microencapsulation may significantly increase the post-thaw recovery and improve the function for cryopreserved rat islets.