Investigating a disintegrin and metalloproteinase-mediated Neuropilin 1 cleavage in autoimmune diabetes

研究自身免疫性糖尿病中解整合素和金属蛋白酶介导的 Neuropilin 1 裂解

• 批准号: 10229420
• 负责人: Stephanie Grebinoski
• 金额: $ 4.6万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10229420
• 关键词: Address; Adoptive Transfer; Affect; Animal Disease Models; Area; Autoantigens; Autoimmune Diabetes; Autoimmune Diseases; Automobile Driving; Beta Cell; Cell physiology; Chronic; Coupled; Data; Development; Diabetes Mellitus; Disease; Disease Progression; Disintegrins; Energy-Generating Resources; FOXP3 gene; FRAP1 gene; Failure; Genes; Glucose; Goals; Human; Immune mediated destruction; Immunotherapeutic agent; Impairment; In Vitro; Inbred NOD Mice; Incidence; Infiltration; Insulin; Insulin Receptor; Insulin-Dependent Diabetes Mellitus; Interferon Type II; Interleukin-10; Islets of Langerhans; Knowledge; Ligands; Lymphocyte; Maintenance; Maps; Mediating; Metalloproteases; Mus; NRP1 gene; Neuropilin-1; Non obese; Onset of illness; PI3K/AKT; Pathway interactions; Phenotype; Play; Predisposition; Prevention; Production; Proto-Oncogene Proteins c-akt; Receptor Signaling; Regulation; Regulatory T-Lymphocyte; Replacement Therapy; Role; Series; Signal Transduction; Site; Structure of beta Cell of islet; Surface; T-Lymphocyte; TNFRSF6 gene; Testing; Time; Tumor-infiltrating immune cells; Work; chronic autoimmune disease; design; diabetic; human model; immunoreaction; immunoregulation; insight; insulitis; interest; islet; mouse model; mutant; novel; overexpression; peripheral tolerance; prevent; receptor; transcription factor; tumor microenvironment

PROJECT SUMMARY/ABSTRACT Type one diabetes (T1D) is a chronic autoimmune disorder affecting millions worldwide and although insulin replacement therapy is lifesaving, it is not a cure.1 Characterized by immune infiltration into the Islets of Langerhan, T1D is caused by the immune mediated destruction of insulin producing β cells, resulting in an impaired ability to use and store glucose as an energy source. Therefore, immune regulation is vital in the prevention of T1D and particularly, Regulatory T cells (Tregs). Data from our lab and others suggest that Tregs a vital extrinsic mechanism of peripheral tolerance to islet autoantigens, the failure of which results in symptomatic T1D.2–8 This phenomenon is referred to as “Treg insufficiency” and is supported by evidence in both humans and animal models of the disease.9–11 Therefore, a complete understanding of the mechanisms driving the T1D-related Treg insufficiency is critical to the development of novel immunotherapeutic treatments for the disorder. Previously, our lab has demonstrated a role for the transmembrane receptor Neuropilin 1 (Nrp1, or CD304) and its ligand, Semaphorin4a (sema4a), in maintaining Treg stability in the tumor microenvironment.12 Here, we defined Treg stability as sustained function, viability, proliferation, and lineage identity. Taking these results into consideration, along with the knowledge that in humans NRP1 has been mapped to one of the T1D-susceptibility regions, we were interested in investigating the role of Nrp1 in the disease progression of T1D.9,13 Surprisingly, however, Treg-restricted deletion of Nrp1 showed no impact on the disease onset in the non-obese diabetic (NOD) mouse model of autoimmune diabetes. This was attributed to a progressive loss of Nrp1 from the surface of intra-islet Tregs which we found to be metalloprotease mediated. Of note, loss of Nrp1 is specific to intra-islet Tregs. This led us to query Nrp1 loss and, consequently, the development of a fragile Treg phenotype in the islets, as a potential mechanism for Treg insufficiency. The mechanisms promoting this ADAM mediated cleavage in the islets are still unknown, though we propose it to be factors specific to the islet microenvironment since cleavage is specific to the islet microenvironment, such as enhanced intra-islet insulin receptor signaling. We hypothesize that insulin receptor signaling drives cleavage of Nrp1 on intra-islet Tregs, therefore, inducing Treg fragility, and that this fragility can be delayed or prevented by increasing Nrp1 expression on intra-islet Tregs. Specifically, we Aim to (1) investigate the impact of insulin receptor signaling on intra-islet Tregs and to understand if insulin exposure in the islet-microenvironment drives the enhanced metalloprotease mediated elimination of Nrp1.. We also Aim to (2) To investigate if enhanced Nrp1 prevents Treg insufficiency in autoimmune diabetes. Successful completion of this proposal will provide enhanced insight into the role that Treg stability, and loss thereof, plays in T1D and may prove translationally relevant to the treatment of T1D.

项目摘要/摘要 1型糖尿病(T1D)是一种影响全球数百万人的慢性自身免疫性疾病，尽管胰岛素 替代疗法是挽救生命的，它不是一种以免疫渗入胰岛为特征的疗法。 朗格罕，T1D是由免疫介导的产生胰岛素的β细胞破坏引起的，导致 利用和储存葡萄糖作为能量来源的能力受损。因此，免疫调节在糖尿病的发病机制中具有重要意义。 预防T1D，特别是调节性T细胞(Tregs)。来自我们实验室和其他人的数据表明，特雷格 外周对胰岛自身抗原耐受的一种重要的外在机制，其失败会导致 有症状的T1D.2-8这种现象被称为“Treg不足”，并得到了 人类和动物的疾病模型。9-11因此，完全理解这种疾病的机制 驱动T1D相关的Treg功能不全是开发新的免疫治疗方法的关键 为这一障碍负责。 此前，我们的实验室已经证明了跨膜受体Neuropilin 1(Nrp1，或CD304)的作用。 它的配体Semaphorin4a(Sema4a)在维持肿瘤微环境中的Treg稳定性方面发挥了重要作用。 Treg的稳定性定义为持续的功能、生存能力、增殖和血统认同。将这些结果纳入 考虑，以及在人类中Nrp1已被映射到T1D易感性之一的知识 令人惊讶的是，我们有兴趣研究Nrp1在T1D.9，13疾病进展中的作用。 然而，在非肥胖糖尿病患者中，Nrp1基因Treg限制性缺失对疾病的发生没有影响 (NOD)自身免疫性糖尿病小鼠模型。这归因于地表Nrp1的逐渐丧失。 我们发现的胰岛内树突状细胞是由金属蛋白酶介导的。值得注意的是，Nrp1的丢失仅限于胰岛内 特雷格斯。这导致我们质疑Nrp1的丢失，因此，在 胰岛，作为Treg功能不全的潜在机制。促进这一过程的机制由亚当调节 胰岛中的卵裂仍然未知，尽管我们认为它是胰岛微环境特有的因素。 因为卵裂是特定于胰岛微环境的，例如增强的胰岛内胰岛素受体信号。 我们假设胰岛素受体信号驱动胰岛内树突上Nrp1的切割，因此， 诱导Treg脆性，这种脆弱性可以通过增加Nrp1的表达来延缓或预防 在胰岛内的树上。具体地说，我们的目标是(1)研究胰岛素受体信号对胰岛内的影响 Tregs和了解胰岛微环境中的胰岛素暴露是否会驱动金属蛋白酶的增强 介导的Nrp1消除..我们还致力于(2)研究增强的Nrp1是否能预防Treg功能不全 自身免疫性糖尿病。成功完成本提案将提供对以下角色的更深入了解 Treg稳定性及其丧失在T1D中起作用，并可能被证明与T1D的治疗有关。