Viral sensor IFIH1 promotes SLE through an altered interferon program

系统性红斑狼疮（SLE）是一种自身免疫性疾病，由遗传和免疫系统相互作用的网络引起。 环境因素SLE与I型干扰素（IFN I）水平升高和病毒感染有关。 先天免疫信号通路中的单核苷酸多态性（SNP）与免疫系统中的免疫缺陷相关。 通过全基因组关联研究，SLE风险增加。一种常见的SNP与以下疾病密切相关： SLE位于病毒dsRNA传感器IFIH 1（rs 1990760）中，导致氨基酸变化（A946 T）。 IFIHI T946变体在SLE发病机制中的确切作用仍不清楚。最近，我们发现敲击- 在表达IFIH 1变体（IFIH 1 T946; Ifih 1 R）的小鼠模型中，显示出提高的基础IFN I表达， 免疫细胞中干扰素刺激基因（ISG）的特征。这种低度干扰素病与 在诱导的SLE模型中抗核自身抗体的持续性增加。因此，Ifih 1 R模型 提供了一个独特的机会，以确定IFIH 1 T946变异体如何引发免疫细胞的提高反应 能促进自身免疫在此，我们将集中于两个目标：1）阐明pDC在升高的细胞凋亡中的作用。 IFIH 1 R小鼠中的IFN特征，以及2）确定IFIH 1 R如何改变CD 4 + T细胞效应子功能和相关的 导致SLE发病的细胞代谢重塑。成功完成这些目标将阐明 IFIH 1 R启动pDC和CD 4 + T细胞促进SLE的转录和代谢机制 发病机制获得的信息将有助于指导基于代谢改变的治疗方法。 SLE和其他自身免疫性疾病中的信号通路。

Systemic lupus erythematosus (SLE) is an autoimmune disease resulting from an interactive web of genetic and environmental factors. SLE is associated with elevated levels of type I interferons (IFN I) and viral infections. Single nucleotide polymorphisms (SNPs) in the innate immune signaling pathway have been linked to an increased risk for SLE by genome wide association studies. One common SNP that is strongly associated with SLE is located in the viral dsRNA sensor, IFIH1 (rs1990760), which results in an amino acid change (A946T). The precise roles of the IFIHI T946 variant in SLE pathogenesis remain unclear. Recently, we showed that a knock- in mouse model expressing the IFIH1 variant (IFIH1T946; Ifih1R) displays heightened basal IFN I expression and a signature of interferon-stimulated genes (ISGs) in immune cells. This low grade interferonopathy correlates with increased persistence of anti-nuclear autoantibodies in an induced SLE model. Therefore, the Ifih1R model provides a unique opportunity to determine how the IFIH1T946 variant primes immune cells for elevated responses that promote autoimmunity. Herein, we will focus on two aims: 1) elucidating the role of pDCs in the elevated IFN signature in Ifih1R mice, and 2) determining how IFIH1R alters CD4+ T cell effector function and associated cellular metabolic remodeling that lead to SLE pathogenesis. Successful completion of these aims will elucidate transcriptional and metabolic mechanisms by which IFIH1R primes pDCs and CD4+ T cells to promote SLE pathogenesis. The information gained will help guide therapeutic approaches based on alterations in metabolic pathways in SLE and other autoimmune diseases.