Characterization of European American and African American Sarcoidosis via Immunogenetics

摘要 结节病是一种肉芽肿性炎症性疾病，常被称为“医学之谜”， 替补演员虽然已知结节病可能涉及宿主遗传易感性和先天性， 适应性免疫反应的感染，有机或无机剂，机制，肉芽肿 形式和疾病严重程度和表现的决定因素仍然难以捉摸。过去几 多年来，我们的团队领导了定义遗传学在结节病中的作用的研究。具体而言，根据我们目前的 我们已经发表了13篇论文，还有3篇即将提交，描述易感基因， 严重程度、祖先特异性和器官特异性影响。然而，相关遗传学的机制 影响结节病的变异体仍然很大程度上未知。我们的建议将通过以下方式缩小这一知识差距： 通过以下方式表征功能变体和它们在其中起作用的组织：1）差异性地鉴定 肉芽肿组织和血液中表达的（DE）基因，2）表征DE的表达， 通过特定细胞类型鉴定先前相关的基因，3）鉴定DE的组织或细胞特异性eQTL， 以前相关的基因，4）创建携带风险等位基因的患者的临床概况，5）复制我们的 在一个独立的队列中发现。具体来说，在目标1中，我们将鉴定新的候选基因及其表达。 在我们将来的结节病易感性机制研究中， 通过DE分析来自EA和AA结节病的全血的RNA测序数据的持久性 患者和匹配的对照以及来自这些相同患者亚组的肉芽肿组织的DE分析 与健康组织相比。此外，我们将使用来自以下的转录组学数据进行eQTL分析： 上述血液和组织以及提供祖先信息的全基因组基因分型数据。在目标2中，我们 定义其中最可能的因果变异起作用的细胞亚群，并识别新的细胞特异性 通过DE分析我们的EA和AA队列中血液来源的单细胞的RNA测序数据的影响 病例和配对对照。为了鉴定细胞类型特异性eQTL，分析基因型和单个eQTL， 还将进行细胞转录组学数据。最后，在目标3中，我们将复制我们的候选人名单， 基因，它们最有可能的致病变体以及它们影响疾病的特定细胞类型， 来自基于人口统计学和临床标准招募的患者队列的血液、组织和单细胞 与我们的因果变异体有关。广泛的基因型将极大地促进我们的工作， 我们现有队列和最近成立的结节病研究单位的临床和环境数据 从这两个方面，我们有强有力的初步数据来支持本文提出的研究。总之，当 这项授权完成后，我们将知道可能的因果变异，它们发挥作用的组织和细胞类型 以及患者的临床特征，其中他们最有可能从中得到丰富， 可以设计机械实验。

ABSTRACT Sarcoidosis is a granulomatous inflammatory disease often dubbed a “medical mystery” yet significantly understudied. While it is known that sarcoidosis likely involves host genetic susceptibility and an innate and adaptive immune response to infectious, organic or inorganic agents, the mechanisms by which granulomas form and the determinants of severity and manifestation of disease remain elusive. Over the past several years, our team has led the charge to define the role of genetics in sarcoidosis. Specifically, under our current funding, we have published 13 papers with 3 more soon to be submitted describing genes for susceptibility, severity, ancestry specific and organ-specific effects. However, the mechanism(s) by which associated genetic variants influence sarcoidosis are still largely unknown. Our proposal will close this knowledge gap by characterizing functional variants and the tissue(s) in which they operate by 1) identifying differentially expressed (DE) genes in granulomatous tissue and blood, 2) characterizing the expression of DE and previously associated genes by specific cell type, 3) identifying tissue or cell-specific eQTLs for DE and previously associated genes, 4) creating clinical profiles of patients carrying risk alleles and 5) replicating our findings in an independent cohort. Specifically, in Aim 1, we will identify novel candidate genes and their most likely causal variants to be investigated in our future mechanistic studies of sarcoidosis susceptibility and persistence via DE analysis of RNA sequencing data of whole blood from both EA and AA sarcoidosis patients and matched controls AND DE analysis of granulomatous tissue from a subset of these same patients compared to healthy tissue. Additionally, we will perform eQTL analysis using the transcriptomic data from blood and tissue described above and ancestry-informative genome-wide genotyping data. In Aim 2, we will define the cell subsets in which the most likely causal variants operate and identify novel cell-specific effects by DE analysis of RNA sequencing data from blood-derived single cells in our cohort of EA and AA cases and matched controls. In order to identify cell-type specific eQTLs, analysis of the genotype and single cell transcriptomic data will also be performed. Finally, in Aim 3 we will replicate our list of candidate genes, their most likely causal variants and the specific cell type in which they influence disease using blood, tissue and single cells from a cohort of patients recruited based on the demographic and clinical criteria that are associated with our causal variants. Our work will be greatly facilitated by the extensive genotype, clinical and environmental data on our existing cohort AND the recently established Sarcoidosis Research Unit from both of which we have strong preliminary data to support the studies proposed herein. In summary, when this grant is complete, we will know the likely causal variants, the tissue and cell-types in which they function and the clinical characteristics of the patients in which they are most likely to be enriched from which detailed mechanistic experiments can be designed.