Epigenetic and chemical approaches to generate function beta cells

描述(申请人提供)：再生产生胰岛素的β细胞以及胰岛移植是治疗1型糖尿病(T1D)最有前途的长期解决方案。这种方法成功的一个主要障碍是器官捐赠者的短缺和同种异体移植后终身免疫抑制的必要性。最近的两个进展，即成功地将体细胞重新编程为多能ES细胞样细胞(IPS)和成功地将人ES细胞分化为功能性胰岛样簇(ILCs)，使得通过将体细胞重新编程为iPS细胞并进行定向分化来产生患者特有的胰岛素分泌ILCs成为可能。事实上，在一项概念验证研究中，我们最近证明了使用这种方法可以从人皮肤成纤维细胞产生胰岛素分泌细胞。尽管这一结果令人鼓舞，但在这项技术的价值能够在临床上实现之前，还有几个障碍需要克服。主要的障碍包括：1)使用携带病毒载体的iPS细胞的安全性问题；2)目前产生功能性β细胞的低效率；3)移植的β细胞的自身免疫破坏。鉴于大型iPS细胞群体正在攻击第一个问题，许多免疫学实验室正在试图解决第三个问题，目前的提案计划使用表观遗传学、化学和ECM方法来解决第二个问题。具体目标是： 1)胎儿和成熟人β细胞的表观遗传学特征； 2)明确的内胚层、胰脏祖细胞和内分泌祖细胞的表观遗传学特征； 3)鉴定促进β细胞分化的化学分子； 4)细胞外基质和其他环境因素对β细胞分化的影响； 公共卫生相关性：β细胞再生是治疗糖尿病的一种很有前途的长期解决方案。在这项研究中，我们建议使用包括表观遗传学、化学、ECM和3D培养在内的综合方法来提高HES和HIPS细胞生成功能性β细胞的效率，以开发T1D的细胞替代疗法。

DESCRIPTION (provided by applicant): Regeneration of insulin-producing beta-cells as well as islet transplantation is the most promising long-term solutions for Type 1 diabetes (T1D) treatment. A major obstacle to the success of this approach is the shortage of organ donors and the necessity for life-long immunosupression after allograft transplantation. Two recent advances, the success in reprogramming somatic cells into pluripotent ES cell-like IPS (induced pluripotent stem) cells and the success in differentiation of human ES cells into functional islet-like clusters (ILCs), have opened the possibility of generating patient-specific insulin-secreting ILCs through the reprogramming of somatic cells into iPS cells followed by guided differentiation. Indeed, in a proof-of-concept study, we have recently demonstrated that insulin-secreting cells can be generated from human skin fibroblasts using this approach. Despite this encouraging result, several obstacles have to be overcome before the value of this technique can be realized clinically. The major obstacles include: 1) safety concerns over the use of iPS cells that harbor viral vectors; 2) low efficiency of current protocols in generating functional beta-cells; 3) autoimmune destruction of the transplanted beta-cells. Given that the large iPS cell community is attacking the first problem and many immunology labs are trying to solve the third problem, the current proposal plans to use epigenetic, chemical, and ECM approaches to attack the second issue. The Specific Aims are: 1) Characterization of epigenetic features of fetal and mature human beta-cells; 2) Characterization of epigenetic features of definitive endoderm, pancreatic progenitors, and endocrine progenitors; 3) Identification of chemical molecules that promote beta-cell differentiation; 4) Characterization of the effect of extracellular matrix and other environmental factors on beta-cell differentiation; PUBLIC HEALTH RELEVANCE: Beta cell regeneration is a promising longterm solution for diabetes treatment. In this study we propse to use a comprehensive approaches that include epigenetic, chemical, ECM and 3D culture to improve the efficiency of generating functional beta-cells from hES and hiPS cells for the development of a cell replacement therapy for T1D.