Improving human pluripotent stem cell derived beta cell transplantation using genetic lineage tracing.

项目总结： 1型糖尿病(T1D)的特征是自身免疫破坏产生胰岛素的β细胞。 进攻。目前尚无治愈方法，T1D患者依赖注射内源性胰岛素， 但长期的并发症和由于胰岛素控制不佳而导致的低血糖风险依然存在。移植物移植 长期存在的T1D患者的孤立身体胰岛导致大约35个月的胰岛素独立， 极大地提高了生活质量。虽然这种贝塔细胞替代疗法已经成为一种潜在的治愈方法 对于T1D来说，由于缺乏丰富的β细胞来源，它的发展受到了阻碍。我们最近做了 证实了从人类体内大规模生产葡萄糖反应性胰岛素产生β-样细胞 多能干细胞。这些细胞可以在动物模型中纠正糖尿病，从而直接解决供者 用这种可行的方法解决短缺问题。然而，当前细胞治疗研究的一个很大程度上被忽视的方面 移植后干细胞来源的贝塔细胞(SBCs)急剧和立即丧失。 这是一个关键问题，如果成功解决，将极大地提高虚拟 所有目前提议提供用于细胞替代治疗目的的SBCS的方法，包括裸体和 封装的。我们的总体假设是，移植SBCs会导致很大比例的 这些细胞，由于几个机制，包括：(1)低氧和营养剥夺介导细胞死亡，(2) 转分化为其他激素表达的细胞类型；(3)剩余的部分SBCs采用较少的 功能性β细胞表型。本次拨款申请的重点有两个方面：(1)准确全面 用遗传谱系追踪和(2)预防表型来阐明SBCs在移植后的命运 联合使用mRNAs瞬时表达抗凋亡基因bcl2的变化和SBC死亡 我们发现生理性氧适应能显著提高移植物存活率。具体地说，我们的血统 示踪分析将全面确定SBC在移植后的细胞变化。我们进一步 预计将准确定义驱动它们的相关分子变化，从而可能提供 此后改善SBC存活率的未被确认的目标。此外，我们希望提供一个有效的和 防止移植后发生的功能性SBC肿块丢失的简单方法。已被占用 总之，这项建议中概述的及时方法与我们独特的专业知识相结合是准备就绪的 为了成功解决T1D患者细胞替代治疗的一个关键问题，保存 移植后SBC存活和功能的即时变化。

Project summary: Type one diabetes (T1D) is characterized by the destruction of insulin-producing beta cells by an autoimmune attack. Currently there is no cure available and T1D patients rely on supply of endogenous insulin via injections, but long-term complications and the risk of hypoglycemia due to poor insulin control persist. Transplantation of isolated cadaveric islets into long-standing T1D patients results in ~35 months of insulin independence, tremendously improving quality of life. While this beta cell replacement therapy has emerged as a potential cure for T1D, its advancement has been hampered by the lack of an abundant beta cell source. We have recently demonstrated the large-scale production of glucose responsive insulin producing beta-like cells from human pluripotent stem cells. These cells can correct diabetes in animal models, thus directly addressing donor shortage with this viable approach. However, a largely neglected aspect of current cell therapy research efforts is the dramatic and immediate loss of stem cell derived beta cells (sBCs) upon transplantation. This is a critical problem that, if successfully resolved, will tremendously increase the efficacy of virtually all current approaches proposing to deliver sBCs for cell replacement therapy purposes, both naked and encapsulated. Our overall hypothesis is that transplantation of sBCs results in the loss of a large proportion of these cells, due to several mechanisms, including: (1) hypoxia and nutrition deprivation mediated cell death, (2) transdifferentiate into other hormone expressing cell types and (3) that part of the remaining sBCs adopt a less functional beta cell phenotype. The focus of this grant application is two-fold: (1) accurately and comprehensively elucidate the fate of sBCs upon transplantation employing genetic lineage tracing and (2) to prevent phenotypical changes and sBC death by temporal expression of the anti-apoptotic gene BCL2 using mRNAs in combination with physiological oxygen adaption shown by us to significantly improve graft survival. Specifically, our lineage tracing analysis will comprehensively define the cellular changes of sBC upon transplantation. We further anticipate to accurately define the associated molecular changes driving them, thus likely providing unacknowledged targets to improve sBC survival thereafter. Furthermore, we except to provide an effective and simple way to prevent the loss of functional sBC mass that is currently occurring upon transplantation. Taken together, the timely approach outlined within this proposal combined with our unique expertise is poised to successfully address a critical problem of cell replacement therapy for T1D patients, the preservation of sBC survival and function immediately upon transplantation.