Characterization of Pathogenic T cells in Alopecia Areata

描述（由申请人提供）：为了改善自身免疫患者的治疗方案，更好地确定所涉及的致病T细胞群至关重要。为了实现这一点，我们将利用一种新的应用程序，首次允许高度集中的解剖致病T细胞库。以斑秃为例，本分析将填补迄今为止在理解自身反应性免疫反应效应机制方面存在的空白。由于严重的斑秃病例很少用全身性药物治疗，这种器官特异性自身免疫性疾病提供了一个独特的机会，可以在没有混杂免疫抑制药物的情况下，纵向表征体内自身反应性免疫反应的演变。到目前为止，还没有研究详细跟踪了从患者最初表现到慢性自身免疫建立的自身反应库。具体假设是，将CDR-3长度库分析与磁分选和流式细胞术相结合，可以在斑秃患者中识别、表征和纵向跟踪致病性自定向T细胞。目标将是确定：这种致病性T细胞反应如何随时间演变，致病性T细胞的表面表型，以及单个致病性T细胞的体内或直接离体细胞因子分泌谱。具体目的如下。特异性目的1：鉴定斑秃患者中活化的克隆型T细胞。特异性目的2：确定随着患者疾病的发展，是否存在相同的克隆型T细胞纵向扩增。特异性目的3：测定致病性T细胞表面活化标志物、趋化因子受体、整合素粘附分子的表达及致病性T细胞的细胞因子分泌谱。

DESCRIPTION (provided by applicant): In order to improve the treatment regimen of patients with autoimmunity it is critical to better define the pathogenic T cell population involved. To accomplish this we will take advantage of a novel application that for the first time will allow a highly focused dissection of the pathogenic T cell repertoire. This analysis will bridge the gap that hitherto existed in understanding the effector mechanisms of an autoreactive immune response, using alopecia areata as a prototypic example. Since severe cases of alopecia areata are rarely managed with systemic agents, this organ-specific autoimmune disease represents a unique opportunity to longitudinally characterize the evolution of an autoreactive immune response in vivo in the absence of confounding immunosuppressive medications. No study to date has followed in detail an autoreactive repertoire longitudinally from a patient's initial presentation to the establishment of chronic autoimmunity. The specific hypothesis being tested is that pathogenic self-directed T cells can be identified, characterized and followed longitudinally in patients with alopecia areata by combining CDR-3 length repertoire analysis with magnetic sorting and flow cytometry. The goal will be to determine: how this pathogenic T cell response evolves over time, the surface phenotype of the pathogenic T cells, and the in vivo or directly ex vivo cytokine secretion profile of the individual pathogenic T cells. The specific aims are as follows. Specific Aim 1: Identify activated clonotypic T cells in patients with alopecia areata. Specific Aim 2: Determine if the same clonotypic T cell expansions are present longitudinally as a patient's disease evolves. Specific Aim 3: Determine the pathogenic T cell's surface expression of activation markers, chemokine receptors, and integrin adhesion molecules as well as the pathogenic T cell's cytokine secretion profile. PUBLIC HEALTH RELEVANCE: Under normal circumstances the immune system protects against foreign invading pathogens such as bacteria and viruses. The T cells are a type of cell of the immune system. These cells have the ability to distinguish viral and bacterial proteins from enogenous "self" proteins and cells that make up your body. Alopecia areata is an autoimmune disease. In autoimmunity the usually protective T cells mistakingly recognize enogenous "self" proteins as foreign, which leads to tissue and organ damage. We propose to study these T cells to determine how the autoimmune disease response evolves over time. We will also characterize the surface of the autoreactive T cells and the molecules they secrete.