Generating novel sources of functional human insulin-secreting cells for T1D modeling

项目总结 胰岛素分泌β细胞移植是治疗1型糖尿病(T1D)的有效方法。至 为了确保这些治疗细胞的供应，许多研究小组正在积极优化方案 通过分化人胚胎干细胞(HESCs)或通过 对成人组织进行重新编程。下一个主要挑战是找到保护 移植来自自身免疫的细胞以实现长期的血糖控制。临床观察 长期以来一直认为T1D患者中存在逃避自身免疫和 继续发挥作用。从临床样本中研究这类细胞是非常具有挑战性的。新研究 需要工具来解决关键问题，即如何生产能够 抵抗自身免疫力。我们实验室最近发现，胰岛素分泌细胞可以很容易地 使用直接重编程方法从小鼠胃组织中产生 因子Ngn3、Pdx1和Mafa(称为NPM因子)。胃源性胰岛素+细胞 胰岛β细胞的主要分子和功能特征，但与天然β细胞不同 细胞。我们将胃胰岛素+细胞移植到NOD小鼠T1D模型中，并制作了 令人惊讶的是，胃胰岛素+细胞不同于天然的胰岛β细胞。 到强烈的免疫攻击，暗示免疫原性降低。这一观察结果引发了 胃源性胰岛素+细胞可能被用作一种新的研究工具 人T1D中免疫-β细胞的相互作用并可能进一步发展为移植 需要最低限度的免疫保护的疗法。在这项提案中，我们将开发新的方法来 用两种分离的方法从人胃组织中培养出具有功能的胰岛素分泌细胞 方法并用多种工具研究其免疫原性，包括人T1D- 衍生的T细胞克隆。我们的最终目标是从机制上洞察免疫反应 T1D中的β细胞，并发现可能减弱或防止自身免疫的新途径 进攻。如果成功，该项目还将为胰岛素分泌的新来源奠定基础 用于治疗性移植治疗T1D的细胞。

PROJECT SUMMARY Transplantation of insulin-secreting beta cells is an effective therapy for Type 1 diabetes (T1D). To secure supplies of these therapeutic cells, many research groups are actively optimizing protocols to derive insulin+ cells by differentiation of human embryonic stem cells (hESCs) or by reprogramming of adult tissues. The next major challenge is to discover methods to protect transplanted cells from autoimmunity to achieve long-term glycemic control. Clinical observations have long suggested existence of beta cells in T1D patients that escape autoimmunity and continue to function. Such cells are very challenging to study from clinical samples. New research tools are needed to address the critical question of how to produce insulin-secreting cells that resist autoimmunity. Our laboratory recently discovered that insulin-secreting cells can be readily produced from murine gastric tissues using a direct reprogramming approach with defined genetic factors Ngn3, Pdx1, and Mafa (referred to as NPM factors). The gastric-derived insulin+ cells share key molecular and functional features of pancreatic beta cells but are not identical to native beta cells. We transplanted gastric insulin+ cells into the NOD murine model of T1D and made the surprising observation that gastric insulin+ cells, unlike native pancreatic beta cells, are not subject to strong immune attack, suggesting reduced immunogenic properties. This observation raised the exciting possibility that gastric-derived insulin+ cells could be employed as a novel tool to study immune-beta cell interactions in human T1D and may be further developed into a transplantation therapy that requires minimal immune protection. In this proposal, we will develop new methods to produce functional insulin-secreting cells from human gastric tissues using two separate approaches and study their immunogenic properties with a variety of tools including human T1D- derived T-cell clones. Our ultimate goal is to gain mechanistic insight into the immune response to beta cells in T1D and to discover novel pathways that may diminish or prevent the autoimmune attack. If successful, this project will also lay the foundation for a novel source of insulin-secreting cells for therapeutic transplantation to treat T1D.