Zhao Min, Amiel Stephanie A, Ajami Sanaz, Jiang Jie, Rela Mohamed, Heaton Nigel, Huang Guo Cai
Diabetes Research Group, King's College London School of Medicine, London, United Kingdom.
PLoS One. 2008 Jul 16;3(7):e2666. doi: 10.1371/journal.pone.0002666.
Pluri-potent bone marrow stromal cells (MSCs) provide an attractive opportunity to generate unlimited glucose-responsive insulin-producing cells for the treatment of diabetes. We explored the potential for human MSCs (hMSCs) to be differentiated into glucose-responsive cells through a non-viral genetic reprogramming approach.
Two HMSC lines were transfected with three genes: PDX-1, NeuroD1 and Ngn3 without subsequent selection, followed by differentiation induction in vitro and transplantation into diabetic mice. Human MSCs expressed mRNAs of the archetypal stem cell markers: Sox2, Oct4, Nanog and CD34, and the endocrine cell markers: PDX-1, NeuroD1, Ngn3, and Nkx6.1. Following gene transfection and differentiation induction, hMSCs expressed insulin in vitro, but were not glucose regulated. After transplantation, hMSCs differentiated further and approximately 12.5% of the grafted cells expressed insulin. The graft bearing kidneys contained mRNA of insulin and other key genes required for the functions of beta cells. Mice transplanted with manipulated hMSCs showed reduced blood glucose levels (from 18.9+/-0.75 to 7.63+/-1.63 mM). 13 of the 16 mice became normoglycaemic (6.9+/-0.64 mM), despite the failure to detect the expression of SUR1, a K(+)-ATP channel component required for regulation of insulin secretion.
Our data confirm that hMSCs can be induced to express insulin sufficient to reduce blood glucose in a diabetic mouse model. Our triple gene approach has created cells that seem less glucose responsive in vitro but which become more efficient after transplantation. The maturation process requires further study, particularly the in vivo factors influencing the differentiation, in order to scale up for clinical purposes.
多能骨髓基质细胞（MSCs）为生成用于治疗糖尿病的无限量葡萄糖反应性胰岛素生成细胞提供了一个有吸引力的机会。我们探索了通过非病毒基因重编程方法将人骨髓间充质干细胞（hMSCs）分化为葡萄糖反应性细胞的潜力。
将两条hMSC系用三个基因进行转染：PDX-1、NeuroD1和Ngn3，无需后续筛选，然后在体外进行分化诱导并移植到糖尿病小鼠体内。人骨髓间充质干细胞表达典型干细胞标志物的mRNA：Sox2、Oct4、Nanog和CD34，以及内分泌细胞标志物：PDX-1、NeuroD1、Ngn3和Nkx6.1。基因转染和分化诱导后，hMSCs在体外表达胰岛素，但不受葡萄糖调节。移植后，hMSCs进一步分化，约12.5%的移植细胞表达胰岛素。移植细胞的肾脏含有胰岛素和β细胞功能所需的其他关键基因的mRNA。移植了经处理的hMSCs的小鼠血糖水平降低（从18.9±0.75降至7.63±1.63 mM）。16只小鼠中有13只血糖恢复正常（6.9±0.64 mM），尽管未能检测到胰岛素分泌调节所需的钾离子ATP通道成分SUR1的表达。
我们的数据证实，hMSCs可被诱导表达足以降低糖尿病小鼠模型血糖的胰岛素。我们的三基因方法产生的细胞在体外似乎对葡萄糖的反应性较低，但移植后效率更高。成熟过程需要进一步研究，特别是影响分化的体内因素，以便扩大规模用于临床。
