Beta Cell Heterogeneity in the Interferon Alpha Response

1个项目摘要 2型糖尿病(T1D)是一种自身免疫性疾病，其特征是产生胰岛素的β细胞因 3是遗传风险和未知环境因素的共同作用。一种主要的假说 环境诱因是病毒感染，在此期间，先天免疫系统释放各种细胞因子和 5种干扰素。干扰素-α的存在与疾病的发病机制密切相关。 6在早发性T1D供者的胰岛中观察到。也有研究表明，干扰素-α可诱导内质网应激，MHC 7Class1过度表达和胰岛细胞凋亡，这是T1D发展的典型特征。多年来，它一直是 8例认为T1D患者的β细胞全部被破坏。最近，这一教条受到了挑战 9在长期存在T1D的供者中发现残留的胰岛素阳性β细胞。这表明β-细胞是 10个异质性，有一个群体的β-细胞能够在高压力条件下生存。有了这些观察 11考虑到，这项提议的中心目标是了解人类β细胞异质性背后的机制 12干扰素-α损伤后ROS反应。我推测ROS积聚了β细胞，被称为“ROSponder” 13含有一个独特的分子标记，促进了ROS积累的这种异质性，导致了这个子集 14的细胞更容易受到氧化应激和细胞凋亡的影响。我将通过三个具体的例子来检验这一假设 15个目标。目标1中的实验旨在表征ROSponders的分子特征，目标是 16确定是什么使他们更容易受到这种ROS积累的影响。在目标2中，我将确定原点 积累ROS的17。在目标3中，我将通过纵向活体成像来确定ROSponders的命运。 18随着这些目标的完成，目标是确定观察到的这种情况的机制和后果 19 ROS反应的异质性。重要的是，通过转录转录，这项工作将旨在识别新的目标 20预防糖尿病条件下的β细胞功能障碍，从而为未来的治疗方法的发展创造条件 21用于疾病预防和/或治疗。对早期糖尿病患者胰岛功能的全面认识 22发病机制和这项资助中建议的尖端技术的使用将使我能够发展成为一名 23岁的科学家，让我走上了在糖尿病领域产生真正和持久影响的轨道。本次F31大奖 24包括一项为期两年的培训计划，旨在实现4个主要目标：1)培养对 25糖尿病研究中使用的技术和概念，2)培训不同显微镜技术的使用，3) 26加强书面和口头科学交流，以及4)培训鼠标模型的使用和使用 27项糖尿病研究。此外，我还将受益于该中心提供的协作研究环境 28印第安纳大学医学院糖尿病和新陈代谢疾病专家。我还将受益于 29个咨询委员会，由精心挑选和建立的NIH资助的调查人员组成的不同团队组成 30和实验室中支持性的研究环境。 31 32 33 34

1 PROJECT SUMMARY 2 Type 1 Diabetes (T1D) is an autoimmune disease characterized by destruction of insulin producing β-cells due 3 to a combination of genetic risk and an unknown environmental trigger. A leading hypothesis for the 4 environmental trigger is viral infection, during which the innate immune system releases various cytokines and 5 interferons. Interferon alpha (IFN-α) has been long implicated in disease pathogenesis, with its presence 6 observed in islets of donors with early-onset T1D. It has also been shown that IFN-α induces ER stress, MHC 7 class 1 overexpression, and islet apoptosis, classical hallmarks of T1D development. For many years it was 8 thought that all β-cells were destroyed in individuals with T1D. Recently, this dogma has been challenged with 9 the discovery of residual insulin positive β-cells in donors with long-standing T1D. This suggests that β-cells are 10 heterogeneous, with one population of β-cells able to survive conditions of high stress. With these observations 11 in mind, the central goal of this proposal is to understand mechanisms behind heterogeneity of human β-cell 12 ROS response following IFN-α insult. I hypothesize that ROS accumulating β-cells, termed ‘ROSponders’ 13 contain a unique molecular signature that promotes this heterogeneity in ROS accumulation, causing this subset 14 of cells to be more susceptible to oxidative stress and apoptosis. I will test this hypothesis through three specific 15 aims. Experiments in aim 1 are designed to characterize the molecular signature of ROSponders, with the goal 16 of identifying what makes them more susceptible to this ROS accumulation. In aim 2, I will determine the origin 17 of accumulating ROS. In aim 3, I will determine the fate of ROSponders through longitudinal intravital imaging. 18 With completion of these aims, the goal is to determine the mechanism and consequence of this observed 19 heterogeneity in ROS response. Importantly, through transcriptomics, this work will aim to identify novel targets 20 to prevent β-cell dysfunction under diabetogenic conditions, allowing for the development of future therapeutics 21 for disease prevention and/or treatment. A comprehensive understanding of islet function in early diabetes 22 pathogenesis and the use of cutting-edge techniques proposed in this grant will enable me to develop as a 23 scientist and set me on a trajectory to make real and lasting impacts in the field of diabetes. This F31 award 24 includes a 2-year training plan designed to achieve 4 main objectives: 1) develop a strong comprehension of 25 techniques and concepts used in diabetes research, 2) train in the use of different microscopy techniques, 3) 26 enhance written and oral scientific communication, and 4) train in the use and handling of mouse models for 27 diabetes research. In addition, I will benefit from the collaborative research environment provided by the Center 28 for Diabetes and Metabolic Diseases at the Indiana University School of Medicine. I will also benefit from an 29 advisory committee consisting of a diverse team of carefully selected and established NIH funded investigators 30 and a supportive research environment in the laboratory. 31 32 33 34