Maintenance of islet function after in vitro culture is crucial for both transplantation and research. Here we evaluated the effects of encapsulation in alginate fiber on the function of human islets which were distributed by the Alberta Islet Distribution Program. Encapsulated human islets from 15 deceased donors were cultured under 5.5 or 25 mM glucose conditions in vitro. The amounts of C-peptide and glucagon secreted from encapsulated islets into the culture media were measured periodically, and immunohistochemical studies were performed. Encapsulated islets maintained C-peptide and glucagon secretion for more than 75 days in 5 cases; in two cases, their secretion was also successfully detected even on day 180. α- and β-cell composition and β-cell survival in islets were unaltered in the fiber after 75 or 180 days of culture. The encapsulated islets cultured with 5.5 mM glucose, but not those with 25 mM glucose, exhibited glucose responsiveness of C-peptide secretion until day 180. We demonstrate that alginate encapsulation enabled human islets to maintain their viability and glucose responsiveness of C-peptide secretion after long-term in vitro culture, potentially for more than for 180 days.

体外培养后胰岛功能的维持对于移植和研究都至关重要。在这里，我们评估了海藻酸盐纤维中的封装对阿尔伯塔岛胰岛分配计划分配的人类胰岛功能的影响。来自 15 名已故捐献者的封装人类胰岛在 5.5 或 25 mM 葡萄糖条件下进行体外培养。定期测量从封装的胰岛分泌到培养基中的 C 肽和胰高血糖素的量，并进行免疫组织化学研究。 5例封装胰岛维持C肽和胰高血糖素分泌75天以上；在两个案例中，即使在第 180 天也能成功检测到它们的分泌。培养 75 或 180 天后，纤维中的 α 和 β 细胞组成以及胰岛中 β 细胞的存活率没有改变。用 5.5 mM 葡萄糖培养的封装胰岛，而不是那些用 25 mM 葡萄糖培养的胰岛，直到第 180 天才表现出 C 肽分泌的葡萄糖反应性。我们证明，藻酸盐封装使人类胰岛在培养后能够保持其活力和 C 肽分泌的葡萄糖反应性。长期体外培养，可能超过 180 天。