Zhang X-L, Yang J-K, Yu M, Xue G-F
Department of Endocrinology Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China.
Transplant Proc. 2009 Dec;41(10):4297-301. doi: 10.1016/j.transproceed.2009.08.061.
Density gradient separation of islets from exocrine tissue is usually performed using Ficoll. However, this reagent significantly increases the cost of isolation. The aim of the present study was to investigate the effects on islet preparations of purification methods using Lymphoprep and Iodixanol (OptiPrep) density gradients.
Pancreata were procured from 46 Wistar rats, loaded with collagenase V (Sigma), and mechanically dissociated using standard procedures. After the digestion phase, the islets purified by 3 methods-Ficoll, Lymphoprep, and Iodixanol (OptiPrep)-were assessed for yields, purity, morphology, and in vitro function.
We expressed the yields as islet equivalents (IEQ, diameter standardizing to 150 microm), showing no significant differences. Compared with the Ficoll group, the purity was significantly higher in the Lymphoprep (P = .005) and Iodixanol (OptiPrep) groups (P = .011). While the viability was >90% in all 3 groups, the viability in the Lymphoprep Group and OptiPrep groups was significantly higher than that of the Ficoll group (P < .001). In vitro islet function did not differ among the 3 experimental groups.
Lymphoprep and Iodixanol were as effective as Ficoll in terms of islet yield and in vitro function. High-purity and high-viability islet cells were obtained using improved Lymphoprep-based or Iodixanol (OptiPrep)-based density gradient methods, potential low-cost substitutes for Ficoll.
胰岛与外分泌组织的密度梯度分离通常使用菲可（Ficoll）进行。然而，这种试剂会显著增加分离成本。本研究的目的是探讨使用淋巴细胞分离液（Lymphoprep）和碘克沙醇（OptiPrep）密度梯度的纯化方法对胰岛制备的影响。
从46只Wistar大鼠获取胰腺，用Ⅴ型胶原酶（Sigma）灌注，并采用标准程序进行机械解离。消化阶段结束后，对通过3种方法（菲可、淋巴细胞分离液和碘克沙醇）纯化的胰岛进行产量、纯度、形态和体外功能评估。
我们将产量表示为胰岛当量（IEQ，直径标准化为150微米），结果显示无显著差异。与菲可组相比，淋巴细胞分离液组（P = .005）和碘克沙醇组（P = .011）的纯度显著更高。虽然3组的活力均>90%，但淋巴细胞分离液组和碘克沙醇组的活力显著高于菲可组（P < .001）。3个实验组的体外胰岛功能无差异。
在胰岛产量和体外功能方面，淋巴细胞分离液和碘克沙醇与菲可同样有效。使用基于改进的淋巴细胞分离液或碘克沙醇的密度梯度方法可获得高纯度和高活力的胰岛细胞，它们可能是菲可的低成本替代品。
