Beta Cell Heterogeneity in the Interferon Alpha Response

1项目概要 2型糖尿病（T1 D）是一种自身免疫性疾病，其特征是由于糖尿病引起的胰岛素产生β细胞的破坏。 3到遗传风险和未知环境触发因素的组合。一个主要的假设是 4.环境触发因素是病毒感染，在此期间，先天免疫系统释放各种细胞因子， 5干扰素。干扰素α（IFN-α）长期以来一直与疾病的发病机制有关， 6在早发性T1 D供体的胰岛中观察到。IFN-α诱导ER应激、MHC 7类1过表达和胰岛细胞凋亡，T1 D发展的经典标志。多年来， 8认为T1 D患者的所有β细胞都被破坏。最近，这一教条受到了挑战， 9.在长期T1 D供体中发现残留的胰岛素阳性β细胞。这表明β细胞是 10异质的，其中一个β细胞群能够在高应激条件下存活。与这些观察结果 考虑到这一点，该提案的中心目标是了解人类β细胞异质性背后的机制， 图12 IFN-α损伤后的ROS应答。我假设ROS积累的β细胞，称为“ROSponders”， 13含有独特的分子特征，其促进ROS积累的这种异质性，导致该亚群 14的细胞更容易受到氧化应激和凋亡的影响。我将通过三个具体的例子来验证这个假设。 15个目标目的1中的实验设计用于表征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。在目标2中，我将确定 17.积累的ROS在目标3中，我将通过纵向活体成像确定ROSponders的命运。 18在完成这些目标后，目标是确定观察到的机制和后果。 19 ROS反应的异质性。重要的是，通过转录组学，这项工作将旨在确定新的靶点 20以预防糖尿病条件下的β细胞功能障碍，从而允许开发未来的治疗方法 21用于疾病预防和/或治疗。对早期糖尿病胰岛功能的全面认识 22发病机制和使用尖端技术提出的这项赠款将使我能够发展为一个 23位科学家，让我走上了在糖尿病领域产生真实的持久影响的轨道。F31奖项 24包括一个为期2年的培训计划，旨在实现4个主要目标：1）培养对 糖尿病研究中使用的25种技术和概念，2）培训使用不同的显微镜技术，3） 26加强书面和口头科学交流，4）训练使用和处理小鼠模型， 27糖尿病研究此外，我将受益于该中心提供的合作研究环境 印第安纳州大学医学院的糖尿病和代谢疾病研究所。我也将受益于一个 29个咨询委员会，由精心挑选和建立的NIH资助的研究人员组成的多元化团队组成 30和实验室的支持性研究环境。 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