Diabetes and Obesity Research Laboratory, Felsenstein Medical Research Center, Sackler Faculty of Medicine, Tel-Aviv University, Beilinson Campus, Petah Tikva 49100, Israel.
Biomaterials. 2011 Mar;32(7):1816-25. doi: 10.1016/j.biomaterials.2010.11.018. Epub 2010 Dec 7.
Insulin-producing pancreatic beta cells are known to be extremely susceptible to the oxidative stress and hypoxia generated following islet transplantation in diabetic patients. We hereby present a novel in vivo selection strategy based on the isolation of insulin-producing cells with enhanced protection after repeated rounds of encapsulation and xenotransplantation. Rat insulinoma INS-1 cells were encapsulated in alginate macrobeads and transplanted in the peritoneal cavity of mice. After 2 days the beads were retrieved and cells were recovered from alginate and propagated in vitro until submitted to a second round of encapsulation and transplantation. Three days later, the surviving cells, named INS-1m2, were isolated from the alginate beads and their protection and functional activity examined. Compared to parental INS-1 cells, the selected INS-1m2 cells were more resistant to hydrogen peroxide, nitric oxide, alloxan and hypoxia. This enhanced protection of the selected cells correlated with the increased level of catalase and poly (ADP-ribose) polymerase expression. Although selected cells expressed more insulin than parental cells, no change in their insulin response to glucose was observed. We conclude that the in vivo selection strategy is a powerful tool for the engineering of insulin producing cells with a broad spectrum of defense properties.
已知产生胰岛素的胰腺β细胞在糖尿病患者胰岛移植后产生的氧化应激和缺氧环境下极其容易受到影响。我们在此提出了一种新的体内选择策略，基于对经过反复包封和异种移植后具有增强保护作用的胰岛素产生细胞的分离。将大鼠胰岛素瘤 INS-1 细胞包封在藻酸盐微球中，并移植到小鼠的腹腔中。2 天后，回收微球，从藻酸盐中回收细胞，并在体外培养，直到进行第二轮包封和移植。3 天后，从藻酸盐微球中分离出存活的细胞，命名为 INS-1m2，并检测其保护和功能活性。与亲本 INS-1 细胞相比，筛选出的 INS-1m2 细胞对过氧化氢、一氧化氮、链脲佐菌素和缺氧的耐受性更强。这种选择性细胞的增强保护作用与过氧化氢酶和多聚（ADP-核糖）聚合酶表达水平的增加相关。尽管选择的细胞表达的胰岛素比亲本细胞多，但它们对葡萄糖的胰岛素反应没有变化。我们得出结论，体内选择策略是一种强大的工具，可用于工程设计具有广谱防御特性的胰岛素产生细胞。
