Autoreactive T Cell Function in Vitiligo

T细胞是自身免疫的效应细胞，它迁移到它们的靶点，产生细胞因子，招募和 激活其他免疫细胞，并摧毁它们在受影响组织中的靶细胞。白癜风是一种自身免疫性疾病 在皮肤中，细胞毒性CD8+T细胞针对产生色素的黑素细胞，这会导致毁容 白色斑点对深色皮肤的人特别有害，从而导致健康差距 我们人口中最脆弱的人。白癜风是一种理想的研究器官机制的疾病。 特异性自身免疫，因为疾病表型可以与分子通路直接相关。那是, 可以观察和采样受影响的皮肤，已知目标细胞和抗原，并进行翻译研究 工具是可用的。白癜风与自身免疫性疾病具有相同的遗传风险等位基因和其他机制，如 在人类患者中更难研究的1型糖尿病和多发性硬化症。通过白癜风，我们可以 全面了解器官特异性自身免疫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细胞反应通常表现为- 被描述为同质的，结果是“要么全有要么全无”。这在一定程度上是由于这样一个事实： 自身免疫通常是基于单个高亲和力CD8+细胞毒克隆转移并激活的。 表面上看。然而，我们发现浸润性白癜风皮损的T细胞是多克隆的和异质性的， 不同的抗原特异性和激活状态。细胞毒性CD8+T细胞在体内组织成簇状单位 似乎攻击黑素细胞的表皮，而CD4+和Treg细胞位于这些细胞的外围- 特斯。综上所述，这些数据表明，白癜风患者的T细胞相互作用比以前在... 站着。我们的中心假设是多克隆CD8+、CD4+和Treg细胞通讯协调Mela- 并测定白癜风的临床表型。 该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来协调自身免疫，以及T细胞如何分泌- 破坏皮肤内的黑素细胞。首先，我们将确定体内的位置，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 与晚期形成的病变、活动期与稳定型疾病、单个与多个部位相比。接下来，我们将扮演- 了解直接从这些皮损的皮肤中分离的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，顺序荧光 原位杂交(seqFISH+)核心和先进的计算方法。此项目可翻译为 方法，因为它将创造新的机制的理解T细胞如何中介启动，进展- Sion，以及白癜风期间自身免疫的维持。这些目标将共同定义分子机制 被自身反应性T细胞利用，并确定关键功能通路，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.