低温培养对仓鼠胰岛分离后中央细胞损害的阻止作用

Prevention of central cell damage of isolated islets of langerhans in hamsters by low temperature preconditioning

目的 探讨仓鼠胰岛分离后中央细胞的损害及阻止其损害的方法。方法 胰岛分离后分别在 37℃培养 7～ 14d ;2 6℃培养 7d ;2 6℃培养 2、4、7d后复温至 37℃继续培养 7d。用显微镜结合录像技术监测胰岛分离后的中央细胞损害情况 ;用计算机辅助分析系统定量算出胰岛的直径、面积以及中央细胞损害的面积 ,算出损害面积的百分比 ;用组织学及末端转移酶标记法 (TUNEL)技术观察胰岛细胞损害的形态学和功能特点。结果 胰岛在 37℃培养 7～ 14d期间 ,直径 >2 0 0 μm的胰岛呈现了中央细胞损害 (包括坏死和凋亡 )。胰岛在 2 6℃培养 7d ,没有出现中央细胞损害。 2 6℃培养7d后复温至 37℃继续培养 7d ,显著性降低了胰岛的中央细胞损害程度。结论 胰岛分离后的中央细胞损害与其直径大小成正比 ;2 6℃培养能够阻止胰岛分离后的中央细胞损害 ;2 6℃培养 7d后复温至 37℃ ,能够阻止大多数 (除直径 >30 0 μm)胰岛的中央细胞损害。

Objective To study central cell damage of isolated islets in hamsters and prevention of central cell damage of isolated islets of Langerhans by low temperature preconditioning ( 26 ℃ ).Methods After islet isolation,temperature ( 37 ℃ ) culture for 7 14 days;low temperature ( 26 ℃ ) culture for 7 days,and low temperature culture with serial rewarming for another in 7 days (from 26 ℃ to 37 ℃ ) at day 2,4,and 7. Central cell damage of the isolated islets was monitored by video-microscopy and analyzed quantitatively by using a computer-assisted image analysis system. The analysis included daily measurement of the diameter and the area of the isolated islets and the area of the central cell damage that developed in those islets over time during culture. Histology and TUNEL assay were used to characterize cell damage and monitor islet function.Results Microscopic analysis showed that during the 7 to 14 days of culture at 37 ℃ ,central cell damage of larger islets with diameters > 200 μm appeared,which included both necrosis and apoptosis. 26 ℃ culture could prevent this central cell damage of isolated islets,and was capable of successfully preconditioning these islets for 37 ℃ culture. Conclusions The central cell damage within isolated islets of Langerhans correlates with the size of the islets; 26 ℃ culture can prevent this central cell damage of isolated islets;A 7-day culture procedure at 26 ℃ can inhibit most of the central cell (excluding diameters> 300 μm ) damage when the islets are rewarmed to 37 ℃ . These novel findings may help to understand the pathophysiology of early loss of islet tissue after transplantation,and may provide a new strategy to improve graft function in the clinical setting of islet transplantation.