扩大标准的供者胰腺在胰岛移植中应用的动物实验

目的 通过系列的动物实验,从供者胰腺(简称:供胰)的热缺血时间、脂肪浸润程度和灌注损伤程度三个方面初步探讨扩大标准的供胰在胰岛移植中的应用. 方法 实验动物采用雄性Wistar大鼠.根据不同的干预冈素,将供胰分为3组,热缺血组、灌注水肿组和脂肪浸润组;另选正常胰腺作为正常对照组.胰岛提取采用原位灌注、胶原酶消化和Ficoll梯度密度离心法.获取的胰岛用双硫腙染色来计算分离的胰岛数目并判断所获取的胰岛纯度;丫啶橙/溴乙啶荧光染色法检测胰岛细胞的活率;体外葡萄糖刺激下胰岛素释放试验检测胰岛功能. 结果 胰腺热缺血15 min内对胰岛的提取量和活率无明显影响,纯度略有下降;热缺血30 min内胰岛的提取量、活率及纯度均明显下降,但胰岛体外功能良好;热缺血45 min时,胰岛体外功能不良.胰腺轻度和中度脂肪浸润时,胰岛提取量及胰岛素释放指数(SI)明显高于正常对照组,而重度脂肪浸润时,胰岛提取量较正常对照组明显降低,且体外功能不良,SI显著下降.胰腺轻度和中度水肿对胰岛提取量、活率、纯度及功能均无明显影响;胰腺重度水肿(含水量＞80%)时,胰岛的提取量、活率及纯度下降,体外功能不良,SI显著低于正常对照组. 结论 供胰质量是影响胰岛提取及功能的重要因素,重度脂肪浸润、严重灌注水肿、热缺血时间超过30 min均影响胰岛提取的数量、纯度及活率,对胰岛功能也有较大影响.

Estimation of expanded criteria donor usability for islet isolation

Objective Islet transplantation has been an effective method for diabetes mellitus. The quality of donor pancreas is important for successful islet isolation. In this study, we evaluated expanded criteria donor usability based on the warm ischemic time, fatty pancreas and perfusion injury. Methods The marginal pancreases include those from cardiac death donor, fatty pancreas and edema pancreas from perfusion injury. Islets were isolated and purified using a modified University of Minnesota method. Islet yield and purity was determined by Dithizone (DTZ) staining and microscopic examination. Islet viability was assessed by AO/EB staining, and islet function was assessed by static glucose stimulation test. Results In the cardiac death donor group, the islet quality, viability, and in vitro function were similar when the warm ischemic time within 15 min. The quality and viability was decreased when the warm ischemic time beyond 30 min, but the function remained well. With 45 min warm ischemic time, insulin release index was decreased significantly. The islet quality, viability, and in vitro function from severe obesity group and severe edema group were decreased obviously. Conclusion Donor factors play a vital role in pancreas transplant outcomes. We concluded that pancreas severe obesity, severe edema and pancreas from cardiac donors (warm ischemic time ＞30 min) are unsuitable for islet isolation.