Jara Claudia, Oyarzun-Ampuero Felipe, Carrión Flavio, González-Echeverría Esteban, Cappelli Claudio, Caviedes Pablo
Programa de Farmacología Molecular y Clínica, ICBM, Facultad de Medicina, Universidad de Chile, Independencia 1027., Casilla 7, Clasificador Nº 7, 8389100 Santiago, Chile.
Advanced Center of Chronic Diseases (ACCDiS), Universidad de Chile, Santiago, Chile.
Diabetol Metab Syndr. 2020 Aug 5;12:66. doi: 10.1186/s13098-020-00573-9. eCollection 2020.
In type I diabetes mellitus (T1DM) pancreatic β cells are destroyed. Treatment entails exogenous insulin administration and strict diet control, yet optimal glycemic control is hardly attainable. Islet transplant could be an alternative in patients with poor glycemic control, but inefficient islet purification and autoimmune response of patients is still a challenge. For these reasons, it is necessary to explore new cellular sources and immunological isolation methods oriented to develop T1DM cell-based therapies.
We postulate human adipose-derived stem cell (hASC) as an adequate source to generate pancreatic islet cells in vitro, and to produce islet-like structures. Furthermore, we propose microencapsulation of these aggregates as an immunological isolation strategy.
hASC obtained from lipoaspirated fat tissue from human donors were differentiated in vitro to insulin (Ins) and glucagon (Gcg) producing cells. Then, insulin producing cells (IPC) and glucagon producing cells (GPC) were cocultured in low adhesion conditions to form cellular aggregates, and later encapsulated in a sodium alginate polymer. Expression of pancreatic lineage markers and secretion of insulin or glucagon in vitro were analyzed.
The results show that multipotent hASC efficiently differentiate to IPC and GPC, and express pancreatic markers, including insulin or glucagon hormones which they secrete upon stimulation (fivefold for insulin in IPC, and fourfold for glucagon, compared to undifferentiated cells). In turn, calculation of the Feret diameter and area of cellular aggregates revealed mean diameters of ~ 80 µm, and 65% of the aggregates reached 4000 µm at 72 h of formation. IPC/GPC aggregates were then microencapsulated in sodium-alginate polymer microgels, which were found to be more stable when stabilized with Ba, yielding average diameters of ~ 300 µm. Interestingly, Ba-microencapsulated aggregates respond to high external glucose with insulin secretion.
The IPC/GPC differentiation process from hASC, followed by the generation of cellular aggregates that are later microencapsulated, could represent a possible treatment for T1DM.
在1型糖尿病（T1DM）中，胰腺β细胞被破坏。治疗需要外源性胰岛素给药和严格的饮食控制，但很难实现最佳血糖控制。胰岛移植可能是血糖控制不佳患者的一种替代方法，但低效的胰岛纯化和患者的自身免疫反应仍是一个挑战。出于这些原因，有必要探索新的细胞来源和免疫隔离方法，以开发基于细胞的T1DM治疗方法。
我们假设人脂肪来源干细胞（hASC）是体外生成胰岛细胞并产生胰岛样结构的合适来源。此外，我们提出将这些聚集体微囊化作为一种免疫隔离策略。
从人类供体的抽脂脂肪组织中获得的hASC在体外分化为产生胰岛素（Ins）和胰高血糖素（Gcg）的细胞。然后，将产生胰岛素的细胞（IPC）和产生胰高血糖素的细胞（GPC）在低粘附条件下共培养以形成细胞聚集体，随后将其封装在海藻酸钠聚合物中。分析了胰腺谱系标志物的表达以及体外胰岛素或胰高血糖素的分泌。
结果表明，多能hASC可有效分化为IPC和GPC，并表达胰腺标志物，包括它们在刺激后分泌的胰岛素或胰高血糖素激素（与未分化细胞相比，IPC中的胰岛素增加五倍，胰高血糖素增加四倍）。反过来，对细胞聚集体的Feret直径和面积的计算显示平均直径约为80μm，并且65%的聚集体在形成72小时时达到4000μm。然后将IPC/GPC聚集体微囊化在海藻酸钠聚合物微凝胶中，发现用Ba稳定时更稳定，平均直径约为300μm。有趣的是，Ba微囊化聚集体在高外部葡萄糖刺激下会分泌胰岛素。
从hASC进行IPC/GPC分化过程，随后生成细胞聚集体并进行微囊化，可能是T1DM的一种潜在治疗方法。
