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“医学谜团”，但意义重大。 未得到充分研究。虽然已知结节病可能与宿主的遗传易感性和先天的和 对感染性、有机或无机因素的适应性免疫反应，肉芽肿的机制 疾病的形式和严重程度和表现的决定因素仍然难以捉摸。在过去的几年中 多年来，我们的团队一直在带头确定遗传学在结节病中的作用。具体地说，在我们目前的 资金，我们已经发表了13篇论文，还有3篇即将提交，描述了易感基因， 严重程度、祖先特有的影响和器官特有的影响。然而，与遗传相关的机制(S) 影响结节病的变异在很大程度上仍是未知的。我们的建议将通过以下方式弥合这一知识差距 通过1)不同的识别来描述功能变体及其作用的组织(S) (2)肉芽肿组织和血液中DE基因的表达； 先前通过特定细胞类型关联的基因，3)识别组织或细胞特异性的DE和 以前的相关基因，4)创建携带风险等位基因的患者的临床档案，5)复制我们的 在独立队列中的研究结果。具体地说，在目标1中，我们将识别新的候选基因及其 在我们未来的结节病易感性的机制研究中最有可能被研究的原因变异 通过对EA和AA结节病患者全血RNA测序数据的DE分析得出持久性 患者和配对对照以及来自这些患者子集的肉芽肿组织的DE分析 与健康组织相比。此外，我们将使用来自以下来源的转录数据进行eQTL分析 上述血液和组织以及具有祖先信息的全基因组基因分型数据。在目标2中，我们将 定义最有可能在其中起作用的因果变体的细胞子集，并确定新的特定细胞 对EA和AA队列中血源性单个细胞RNA测序数据进行DE分析的效果 病例和配对对照。为了确定细胞类型的特异性eQTL，分析了基因和单个 还将执行细胞转录数据。最后，在目标3中，我们将复制我们候选名单 基因，它们最可能的因果变异，以及它们影响疾病的特定细胞类型 根据人口学和临床标准招募的一组患者的血液、组织和单个细胞 与我们的因果变异相关的基因。广泛的基因分型将极大地促进我们的工作， 关于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，我们都有强有力的初步数据来支持本文提出的研究。总而言之，当 这项捐赠是完整的，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 以及最有可能从中得到丰富的患者的临床特征，详细说明 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.