Immune responses to islet amyloid in beta-cell death

β细胞死亡中对胰岛淀粉样蛋白的免疫反应

• 批准号: 10618288
• 负责人: Andrew T. Templin
• 金额: --
• 依托单位: RLR VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10618288
• 关键词: Address; Advisory Committees; Affect; Amyloid; Amyloid deposition; Antigens; Apoptosis; Award; Beta Cell; Blindness; CD3 Antigens; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; Cell Death; Cell Death Signaling Process; Cell physiology; Cells; Cellular Structures; Cellular biology; Cessation of life; Characteristics; Data; Diabetes Mellitus; Disease; Exhibits; Functional disorder; General Population; Goals; Health Benefit; Healthcare Systems; Heart Diseases; Human; Immune; Immune response; Immune system; Immunologist; Immunology; In Vitro; Individual; Inflammation; Insulin; Insulin-Dependent Diabetes Mellitus; Interferon Type II; Interleukin-1 beta; International; Investigation; Islets of Langerhans; K-Series Research Career Programs; Kidney Failure; Laboratories; Literature; Location; Lymphocyte; Lymphocytic Infiltrate; Lytic; MAPK8 gene; Macrophage; Mediating; Mentors; Messenger RNA; Modeling; Molecular; Molecular Biology; Morbidity - disease rate; Mus; Non-Insulin-Dependent Diabetes Mellitus; Pancreas; Pathogenesis; Pathologic; Pathway interactions; Patients; Phenotype; Phosphorylation; Phosphotransferases; Play; Positioning Attribute; Process; Production; Protein Kinase Interaction; Proteins; Publications; Qualifying; RIPK1 gene; RIPK3 gene; Rag1 Mouse; Reporting; Research; Role; Secretory Cell; Signal Pathway; Signal Transduction; Stroke; T-Lymphocyte; TNF gene; TNFRSF1A gene; Testing; Time; Training; Transgenic Mice; Type 2 diabetic; United States Department of Veterans Affairs; Veterans; amyloid formation; career; career development; immunogenic; immunogenic cell death; in vivo; inhibitor; islet; islet amyloid polypeptide; mRNA Expression; military veteran; mixed lineage kinase 3; mouse model; novel; novel strategies; novel therapeutic intervention; preservation; prevent; recruit; response; sound

The applicant seeks a VA Career Development Award-2 (CDA-2) to further our understanding of the pathogenesis of β-cell loss in type 2 diabetes (T2D) and support his career development at the Veteran’s Affairs Puget Sound Health Care System (VAPSHCS). His expertise in cell and molecular biology, islet inflammation, and islet amyloid deposition, along with his strong mentors (Steven Kahn and Jane Buckner), collaborators (Andrew Oberst and Matthias von Herrath), Advisory Committee (Rebecca Hull, Jerry Palmer, Alvin Powers), and location at the VAPSHCS, make him uniquely qualified to execute the proposed studies. With the support of this award, he will investigate novel and underappreciated aspects of β-cell death in T2D, interact with internationally-recognized diabetologists and immunologists, and undertake didactic and laboratory-based immunology training. These activities will allow the candidate to author additional high impact publications, gain research independence, and position himself to successfully compete for a VA Merit Review Award. The scientific goals of this proposal are to define the roles of necroptosis (a novel form of cell death) and T cells in islet amyloid-induced β-cell loss in order to develop new treatments for individuals afflicted by T2D. Islet amyloid is a pathologic hallmark of T2D, where it elicits islet inflammation and β-cell death. Investigation of the mechanisms of amyloid-induced β-cell death have focused largely on apoptosis signaling. Preliminary data in this application show for the first time that a recently described alternative form of cell death signaling called necroptosis is activated by islet amyloid formation. These data also show that components of this cell death pathway, including receptor interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like pseudokinase (MLKL), are present in β cells. A central characteristic of necroptosis is its ability to elicit immune responses to cellular antigens that are released by this form of lytic cell death. Consistent with this process occurring in response to islet amyloid, preliminary data show that amyloid-laden islets exhibit significantly higher T cell abundance and mRNA expression. Based on these findings and the literature, I hypothesize that islet amyloid-induced TNFα production by macrophages leads to RIPK3-mediated β-cell necroptosis, which results in T lymphocyte recruitment to amyloid-laden islets and exacerbation of amyloid-induced β-cell dysfunction and death. To test this hypothesis, the following specific aims are proposed: Specific Aim 1: Determine the role of RIPK3 signaling in amyloid-induced β-cell death, β-cell dysfunction, and islet immune responses. The contribution of RIPK3 signaling to islet amyloid-induced β-cell death will be determined in vitro using 1) a RIPK3 inhibitor, and 2) islets from Ripk3-/- mice crossed with amyloid-prone human IAPP (hIAPP) transgenic mice. These Ripk3-/- x hIAPP mice will also be used to determine whether RIPK3 loss ameliorates amyloid-induced islet immune responses and β-cell death in vivo. Specific Aim 2: Determine the role of T lymphocytes in amyloid-induced β-cell death and dysfunction. Islet amyloid-prone mice lacking lymphocytes (Rag1-/- x hIAPP) will be used to determine the role of T cells in amyloid-induced β-cell death and dysfunction, and in amyloid deposition itself. The relationship between islet lymphocytes, amyloid deposition, inflammation, and β-cell death will be evaluated 1) in vitro using isolated islets, and 2) in vivo using this novel amyloid-prone, lymphocyte deficient mouse model. The relationship between islet amyloid deposition, immune cell abundance, and β-cell death will also be evaluated in human pancreas sections.

申请人寻求VA职业发展奖-2（CDA-2），以进一步了解 2型糖尿病（T2 D）中β细胞丢失的发病机制，并支持他在退伍军人学院的职业发展 普吉特海湾卫生保健系统（VAPSHCS）。他在细胞和分子生物学、胰岛 炎症和胰岛淀粉样蛋白沉积，沿着他强大的导师（史蒂芬·卡恩和简·巴克纳）， 合作者（Andrew Oberst和Matthias von Herrath），咨询委员会（Rebecca船体，Jerry Palmer， Alvin Powers）和VAPSHCS的位置，使他唯一有资格执行拟议的研究。 在该奖项的支持下，他将研究T2 D中β细胞死亡的新颖和未被充分认识的方面， 与国际公认的糖尿病学家和免疫学家互动，并进行教学和 实验室免疫学培训。这些活动将使候选人能够撰写更多的高影响力 出版物，获得研究独立性，并使自己能够成功地竞争VA Merit Review 奖 这项建议的科学目标是确定坏死性凋亡（一种新的细胞死亡形式）和T细胞的作用。 胰岛淀粉样蛋白诱导的β细胞损失中的细胞，以便为患有T2 D的个体开发新的治疗方法。 胰岛淀粉样蛋白是T2 D的病理学标志，其中它引起胰岛炎症和β细胞死亡。调查 淀粉样蛋白诱导的β细胞死亡的机制主要集中在凋亡信号转导上。初步 本申请中的数据首次表明，最近描述的细胞死亡信号传导的替代形式 称为坏死性凋亡是由胰岛淀粉样蛋白形成激活的。这些数据还表明， 死亡途径，包括受体相互作用蛋白激酶3（RIPK 3）和混合谱系激酶结构域样 假激酶（MLKL）存在于β细胞中。坏死性凋亡的一个中心特征是它能够引起免疫反应， 对这种形式的溶解性细胞死亡释放的细胞抗原的反应。与此过程一致 在对胰岛淀粉样蛋白的反应中发生，初步数据显示，淀粉样蛋白负载的胰岛表现出显著的 更高的T细胞丰度和mRNA表达。 基于这些发现和文献，我假设胰岛淀粉样蛋白诱导TNFα的产生是通过 巨噬细胞导致RIPK 3介导的β细胞坏死性凋亡，这导致T淋巴细胞募集， 淀粉样蛋白负载的胰岛和淀粉样蛋白诱导的β细胞功能障碍和死亡的恶化。 为了检验这一假设，提出了以下具体目标： 具体目的1：确定RIPK 3信号传导在淀粉样蛋白诱导的β细胞死亡、β细胞功能障碍和 胰岛免疫反应。RIPK 3信号传导对胰岛淀粉样蛋白诱导的β细胞死亡的贡献将是 使用1）RIPK 3抑制剂，和2）来自RIPK 3-/-小鼠的胰岛与淀粉样蛋白倾向性小鼠杂交， 人IAPP（hIAPP）转基因小鼠。这些Ripk 3-/- x hIAPP小鼠也将用于确定是否 RIPK 3缺失改善体内淀粉样蛋白诱导的胰岛免疫应答和β细胞死亡。 具体目标2：确定T淋巴细胞在淀粉样蛋白诱导的β细胞死亡和功能障碍中的作用。胰岛 将使用缺乏淋巴细胞的淀粉样蛋白倾向小鼠（Rag 1-/-xhIAPP）来确定T细胞在 淀粉样蛋白诱导的β细胞死亡和功能障碍，以及淀粉样蛋白沉积本身。胰岛与 淋巴细胞、淀粉样蛋白沉积、炎症和β-细胞死亡将1）使用分离的 胰岛，和2）在体内使用这种新的淀粉样蛋白倾向，淋巴细胞缺陷小鼠模型。的关系 胰岛淀粉样蛋白沉积、免疫细胞丰度和β细胞死亡之间的关系也将在人类中进行评估。 胰腺切片。