Cellular auto-immune mechanisms of narcolepsy

发作性睡病的细胞自身免疫机制

• 批准号: 9404243
• 负责人: Igor J Koralnik
• 金额: $ 27.13万
• 依托单位: RUSH UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9404243
• 关键词: Cellular; auto; immune; mechanisms; narcolepsy

Narcolepsy with Cataplexy (N/C) is a common sleep disorder, but very little is understood about the underlying mechanism that causes N/C and why symptoms are severe in some patients but not in others. N/C is caused by selective loss of the hypothalamic neurons that produce the orexin neuropeptides and is strongly associated with the Major Histocompatibility Complex (MHC) class II allele DQB1 *0602. We hypothesize that N/C is caused by CD4+ or CD8+ T cells response directed against the hypothalamic neurons producing the orexin neuropeptides, and that a more aggressive immune response results in increased severity of N/C. This hypothesis is supported by a number of publications suggesting a causal role of the cellular immune response in N/C as well as our own preliminary data. Our long term goal is to understand the cause of N/C and the determinants of disease severity. In doing so, we will also devise a much needed blood test for the early diagnosis of NC and prediction of disease severity. Our objectives are to determine whether N/C patients mount a cellular immune response to orexin peptides and whether this response is associated with more severe symptoms. The rationale is that these proposed studies will enable us to develop a blood test for early diagnosis of N/C and predictor of disease severity. To test these hypotheses, we will pursue the following set of Specific Aims: Aim 1) Correlate disease severity with the cellular immune response to orexin neuropeptides in DQB1 *0602+ Narcolepsy with Cataplexy patients. We will measure narcolepsy symptoms severity using well- validated scales and correlate symptom severity with the reactivity of CD4+ or CD8+ T cells to orexin peptides using three different assays: 1) Intracellular Cytokine Staining (ICS) assay 2) Luminex xMAP bead array on cell culture supernatant and 3) RT-qPCR for cytokine mRNA on cellular RNA . Aim 2) Identify immunodominant orexin epitopes recognized by CD4+ or CD8+ T cells in DQB1 *0602+ Narcolepsy with Cataplexy patients. We will map orexin epitopes in N/C patients using ICS and devise a diagnostic blood test and predictor of disease severity for N/C. The approach is innovative, because it departs significantly from the status quo by focusing on the cellular mechanisms leading to N/C. The proposed research is significant because it will allow us to identify the immunopathogenic mechanisms leading to N/C, develop a blood test for early diagnosis of N/C and predict disease severity. The knowledge gained from these studies will also have far reaching implications in advancing the fields of Sleep Disorders and Neuro-Immunology.

发作性睡病伴紧张症（N/C）是一种常见的睡眠障碍，但对其潜在机制知之甚少。 导致N/C的机制以及为什么某些患者的症状严重而另一些患者则不严重。N/C是由 通过产生食欲素神经肽的下丘脑神经元的选择性丧失， 主要组织相容性复合体（MHC）II类等位基因DQB 1 *0602。我们假设N/C是 由针对产生食欲素的下丘脑神经元的CD 4+或CD 8 + T细胞应答引起 神经肽，并且更积极的免疫应答导致N/C的严重程度增加。这 许多出版物支持这一假设，表明细胞免疫应答的因果作用 以及我们自己的初步数据。我们的长期目标是了解N/C的原因和 疾病严重程度的决定因素。在这样做的同时，我们还将设计一种急需的血液测试， 诊断NC和预测疾病严重程度。我们的目标是确定N/C患者是否 对食欲肽产生细胞免疫反应，以及这种反应是否与更多的 严重的症状。理由是，这些拟议的研究将使我们能够开发一种血液测试， N/C的诊断和疾病严重程度的预测。 为了检验这些假设，我们将追求以下一组具体目标： 目的1）将疾病严重程度与DQB 1中对食欲素神经肽的细胞免疫应答相关联 *0602+发作性睡病伴紧张症患者。我们将使用- 验证量表，并将症状严重程度与CD 4+或CD 8 + T细胞对食欲肽的反应性相关联 使用三种不同的测定：1）细胞内细胞因子染色（ICS）测定2）细胞上的Luminex xMAP珠阵列 培养物上清液和3）细胞RNA上细胞因子mRNA的RT-qPCR。 目的2）鉴定DQB 1 *0602+中CD 4+或CD 8 + T细胞识别的免疫显性食欲素表位 发作性睡病伴cataepsy患者。我们将使用ICS在N/C患者中绘制食欲素表位，并设计一个 诊断性血液检查和N/C疾病严重程度的预测因子。 这种方法是创新的，因为它通过专注于蜂窝网络， 导致N/C的机制。这项拟议中的研究意义重大，因为它将使我们能够确定 导致N/C的免疫病理机制，开发用于早期诊断N/C的血液测试并预测 疾病严重程度。从这些研究中获得的知识也将产生深远的影响， 推进睡眠障碍和神经免疫学领域。