Autoreactive T Cell Function in Vitiligo

T细胞是自身免疫的效应细胞，其迁移以找到它们的靶标，产生细胞因子， 激活其他免疫细胞，并破坏受影响组织中的靶细胞。白癜风是一种自身免疫性疾病 细胞毒性CD 8 + T细胞靶向制造色素的黑色素细胞，从而导致毁容 白色斑点，这是特别具有破坏性的那些与深色皮肤，从而导致健康的差距， 我们人口中最脆弱的群体白癜风是一种理想的疾病，其中研究机制的器官- 特异性自身免疫，因为疾病表型可与分子途径直接相关。也就是说， 受影响的皮肤可以观察和采样，靶细胞和抗原是已知的， 工具可用。白癜风与自身免疫性疾病，如 1型糖尿病和多发性硬化症，这在人类患者中更难研究。通过白癜风，我们可以 发展器官特异性自身免疫的全面了解，因为它在人体组织内的进展。 在白癜风和其他人类自身免疫性疾病的模型中，自身反应性T细胞反应通常是特征性的。 其特征为同质的，具有“全有或全无”的结果。这部分是由于这样的事实，即小鼠模型的 自身免疫通常基于单个高亲和力CD 8+细胞毒性克隆转移和活化的阿尔蒂， 正式的然而，我们发现浸润白癜风皮损的T细胞是多克隆的和异质的， 不同的抗原特异性和激活状态。细胞毒性CD 8 + T细胞在体内组织成簇单位。 表皮似乎攻击黑素细胞，而CD 4+和Treg细胞位于这些细胞团的外围。 特斯总之，这些数据表明，白癜风中的T细胞相互作用比以前更复杂， 站着。我们的中心假设是，多克隆CD 8+，CD 4+和Treg细胞通讯协调mela， 黑色素细胞破坏和确定白癜风临床表型。 本项目将确定自身反应性T细胞克隆多样性和定位如何定义临床疾病 表型、T细胞亚型如何相互作用以协调自身免疫以及T细胞如何运作- 破坏皮肤内的黑色素细胞。首先，我们将确定在体内的位置，空间关系， 不同临床表型白癜风患者T细胞克隆的功能特点，如早期初发型白癜风患者， vs.晚期病变、活动性与稳定性疾病以及单个与多个部位。接下来，我们将性格- 鉴定直接从这些病变皮肤分离的T细胞的功能和反应性。我们将使用主T 细胞和皮肤器官培养，T细胞功能测定，T细胞受体亲和力测定，连续荧光 原位杂交（seqFISH+）核心和先进的计算方法。该项目是翻译在 方法，因为它将创造新的机制理解T细胞如何介导的启动，进展， 白癜风的治疗方法有哪些？这些目标将共同定义分子机制 利用自身反应性T细胞和确定关键的功能途径，支持新的治疗干预措施。

T cells are effector cells of autoimmunity that migrate to find their targets, produce cytokines that recruit and activate other immune cells, and destroy their target cells in affected tissue. Vitiligo is an autoimmune disease of the skin in which cytotoxic CD8+ T cells target pigment-making melanocytes, which results in disfiguring white spots that are particularly devastating for those with darker skin and thus leads to health disparities for the most vulnerable of our population. Vitiligo is an ideal disease in which to investigate mechanisms of organ- specific autoimmunity because disease phenotype can be directly correlated to molecular pathways. That is, affected skin can be observed and sampled, target cells and antigens are known, and translational research tools are available. Vitiligo shares genetic risk alleles and other mechanisms with autoimmune diseases like type 1 diabetes and multiple sclerosis that are more difficult to study in human patients. Through vitiligo we can develop a comprehensive understanding of organ-specific autoimmunity as it progresses within human tissue. In vitiligo and models of other human autoimmune diseases, autoreactive T cell responses are commonly char- acterized as homogenous, with an “all or nothing” result. This is partly due to the fact that mouse models of autoimmunity are frequently based on a single high-affinity CD8+ cytotoxic clone transferred and activated arti- ficially. However, we found that T cells infiltrating vitiligo skin lesions are polyclonal and heterogeneous, with different antigenic specificities and activation states. Cytotoxic CD8+ T cells organize into clustered units within the epidermis that appear to attack melanocytes, while CD4+ and Treg cells are at the periphery of these clus- ters. Together, these data indicate that T cell interactions in vitiligo are more complex than previously under- stood. Our central hypothesis is that polyclonal CD8+, CD4+, and Treg cell communications coordinate mela- nocyte destruction and determine vitiligo clinical phenotypes. This project will determine how autoreactive T cell clonal diversity and localization define the clinical disease phenotype, how T cell subtypes interact with each other to coordinate autoimmunity, and how T cells orches- trate melanocyte destruction within the skin. First, we will determine the in vivo location, spatial relationships, and functional characteristics of T cell clones in different clinical phenotypes of vitiligo, such as early incipient vs. late established lesions, active vs. stable disease, and single vs. multiple locations. Next, we will character- ize the function and reactivity of T cells isolated directly from the skin of these lesions. We will use primary T cell and skin organ culture, T cell functional assays, T cell receptor affinity assays, the sequential fluorescence in situ hybridization (seqFISH+) Core, and advanced computational methods. This project is translational in approach because it will create new mechanistic understanding of how T cells mediate the initiation, progres- sion, and maintenance of autoimmunity during vitiligo. Together these aims will define molecular mechanisms utilized by autoreactive T cells and identify key functional pathways, supporting new therapeutic interventions.