Genetic regulation of intestinal epithelial cell innate immune signaling in human type 1 diabetes

人类1型糖尿病肠上皮细胞先天免疫信号的基因调控

• 批准号: 10047614
• 负责人: Shannon Margaret Wallet
• 金额: $ 7.23万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-01-05 至 2020-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10047614
• 关键词: Genetic; regulation; intestinal; epithelial; cell

Project Abstract/Summary Type 1 Diabetes (T1D) is an autoimmune disease with both genetic and environmental contributions, yet a single environmental factor has yet to be identified. We propose that rather than the specific identity of the environmental factor, the way in which an environmental signal is received is most important to disease. Among individuals at risk of developing T1D, seroconversion to islet autoantibody (IA) production is the best and earliest biological predictor of disease progression. Thus, critical events leading to the destructive β cell autoimmunity associated with T1D are linked to the development of IAs. In subjects with high risk HLA alleles, 9 gene regions marked by single nucleotide polymorphisms (SNPs) are associated with IA seroconversion. Our collaborator’s analysis of these IA risk loci reveals enrichment for genes/proteins that regulate only three cell signaling pathways (RAS/MAPK, PI3K/AKT and JAK/STAT), whereby four IA seroconversion risk variants (PTPN22, SH2B3, ERBB3 and UBASH3A) each impact all three. Thus, we propose that regulation of environmental sensing is at least in part controlled by the one or more of these risk variants associated with the development of IAs. Appropriate communication of the gastrointestinal tract (GI) with the environment is required for local and systemic immunologic homeostasis, which is in part regulated by the intestinal epithelial cell (IEC) through their physical and biochemical interactions with innate and adaptive immune populations. To this end, contribution of immunity within the GI tract to the expression of autoimmunity at distal sites has been previously demonstrated. Thus we propose that the seroconversion risk variants affect immune signaling pathways within the IEC contributing to the maintenance of autoimmunity in T1D, through the secondary expansion and/or polarization of autoreactive effector T-cells. To study human disease, a major need is cell-specific human isogenic systems that can be used to dissect the role of individual T1D risk gene variant alleles. Our preliminary studies support use of a disease-in- a-dish strategy that pairs human induced pluripotent stem cells (iPSCs) with CRISPR/Cas9 gene modification to fulfill these needs. We propose to couple iPSCs and CRISPR/Cas9 technology with our method of reproducible primary human IECs culture to achieve haploinsufficient, mono-allelic homozygosity at risk or protective alleles to evaluate alterations in IEC-immune mechanisms which contribute to the maintenance of βcell autoimmunity.

项目摘要/总结 1 型糖尿病 (T1D) 是一种自身免疫性疾病，遗传和环境都有影响，但 我们建议，尚未确定的是单一环境因素，而不是具体的身份。 其中环境因素中，接受环境信号的方式对疾病影响最为重要。 对于有患 T1D 风险的个体，血清转化为胰岛自身抗体 (IA) 的产生是最好且最早的 因此，导致破坏性β细胞自身免疫的关键事件。 在具有高风险 HLA 等位基因的受试者中，与 T1D 相关的 9 个基因区域与 IAs 的发生有关。 以单核苷酸多态性 (SNP) 为标志的病毒与我们合作者的 IA 血清转化相关。 对这些 IA 风险位点的分析揭示了仅调节三种细胞信号传导的基因/蛋白质的富集 途径（RAS/MAPK、PI3K/AKT 和 JAK/STAT），其中四种 IA 血清转化风险变异（PTPN22、 SH2B3、ERBB3 和 UBASH3A) 各自影响这三者，因此，我们建议对环境进行监管。 传感至少部分由与开发相关的这些风险变体中的一个或多个控制 的 IAs。 胃肠道（GI）与环境的适当沟通对于局部和环境来说是必需的。 全身免疫稳态，部分由肠上皮细胞（IEC）通过其 与先天性和适应性免疫群体的物理和生化相互作用。 先前已证明胃肠道内对远端部位自身免疫表达的免疫力。 因此，我们认为血清转化风险变异会影响 IEC 内的免疫信号通路 通过二次扩张和/或极化，有助于 T1D 自身免疫的维持 自身反应性效应T细胞。 为了研究人类疾病，一个主要需求是细胞特异性的人类同基因系统，该系统可用于 剖析个体 T1D 风险基因变异等位基因的作用 我们的初步研究支持使用疾病相关基因。 将人类诱导多能干细胞 (iPSC) 与 CRISPR/Cas9 基因修饰配对的培养皿策略 我们建议将 iPSC 和 CRISPR/Cas9 技术与我们的可重复方法结合起来。 原代人类 IEC 培养物可实现单倍体不足、处于危险或保护性等位基因的单等位基因纯合性 评估有助于维持 β 细胞自身免疫的 IEC 免疫机制的改变。