Impact of Loss-of-function NADPH Oxidase Variants on B cell Activation in SLE

功能丧失的 NADPH 氧化酶变体对 SLE 中 B 细胞激活的影响

基本信息

批准号：
10577834
负责人：
Shaun William Jackson
金额：
$ 53.66万
依托单位：
SEATTLE CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-02-01 至 2025-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10577834
关键词：
Acceleration Adaptive Immune System Animals Antibodies Antigens Apoptotic Autoantibodies Autoantigens Autoimmune Diseases Autoimmune Responses Autoimmunity Autophagocytosis B-Cell Activation B-Cell Antigen Receptor B-Lymphocytes Biochemical Cell Lineage Cell physiology Cells Chronic Complex Data Defect Development Disease Endosomes Event Exhibits Future Gene Deletion Generations Genes Genetic Models Genetic Polymorphism Genotype Goals Hematopoietic Human Human Genetics Immune Immune Tolerance Immune system Immunization Immunoglobulin Class Switching Immunologics In Vitro Individual Integrin alphaV Integrin alphaVbeta3 Integrins Investments Knockout Mice Ligands Link LoxP-flanked allele Lupus Maps Memory Modeling Mus Myelogenous Myeloid Cells NADPH Oxidase Nucleic Acid Regulatory Sequences Nucleic Acids Odds Ratio Organ Oxidases Pathogenesis Pathogenicity Pathway interactions Peripheral Blood Mononuclear Cell Phagocytes Phagocytosis Production Publishing Reactive Oxygen Species Receptor Signaling Regulation Regulator Genes Risk Signal Pathway Source Structure of germinal center of lymph node System Systemic Lupus Erythematosus T-Lymphocyte TLR7 gene Testing Tissues Toll-like receptors Untranslated RNA Variant Viral Antigens Virus Diseases Virus-like particle autoreactive B cell cellular imaging design disorder risk genetic variant genome wide association study humoral immunity deficiency imaging approach in vivo insight loss of function loss of function mutation new therapeutic target novel pathogenic autoantibodies prevent recruit response risk variant systemic inflammatory response targeted treatment trafficking

项目摘要

Project abstract Genome-wide association studies (GWAS) have identified immune pathways linked to the pathogenesis of systemic lupus erythematosus (SLE). However, despite these insights, our understanding of how individual genetic variants promote autoimmunity remains poor. Loss-of-function mutations in genes of the phagocytic NADPH oxidase complex (NOX2), including NCF1 and NCF2, have been linked with the pathogenesis of SLE and other humoral autoimmune diseases. The current model for how reduced NOX2 activity promotes lupus development focuses on defects in the clearance of apoptotic material by phagocytic myeloid lineages. While myeloid defects likely contribute to disease risk, we hypothesize that a parallel B cell-intrinsic mechanism underlies the profound increase risk of SLE in human carriers of NCF1 and NCF2 variants. In addition to the production of pathogenic autoantibodies, recent studies have demonstrated that B cells can promote lupus pathogenesis by initiating immune tolerance breaks and facilitating the generation of spontaneous germinal centers (GC). The activation of autoreactive B cells in SLE requires B cell-intrinsic expression of the endosomal toll-like receptors TLR7 and TLR9, and our published and preliminary data show that reduced NOX2 activity results in dysregulated endosomal TLR signaling by impacting non-canonical autophagy pathways. Based on these data, we hypothesize that a B cell-specific reduction in NOX2 activity will result in enhanced TLR- dependent GC formation and the development of humoral autoimmunity. We will test this idea via parallel in vivo and in vitro mechanistic studies. In Aim 1, we will test whether B cell-intrinsic deletion NOX2 component genes results in enhanced TLR-dependent GC responses using a well-characterized model of viral infection. In Aim 2, we will study whether reduced NOX2 activity promotes autoantibody production and humoral autoimmunity in murine SLE. Finally, in Aim 3, we will use biochemical and cell imaging approaches to test whether NAPDH oxidase activity impacts B cell TLR signaling and non-canonical autophagy pathways using both murine genetic models and gene-edited human B cells. Together, these studies promise to advance our understanding of lupus pathogenesis and may inform the design of future targeted therapies for human SLE.

项目摘要全基因组关联研究（GWAS）已经确定了与疾病发病机制相关的免疫途径系统性红斑狼疮（SLE）。然而，尽管有这些见解，我们对个人如何理解促进自身免疫的遗传变异仍然很差。吞噬细胞基因功能丧失突变 NADPH 氧化酶复合物 (NOX2)，包括 NCF1 和 NCF2，与 SLE 的发病机制有关和其他体液性自身免疫性疾病。 NOX2 活性降低如何促进狼疮的当前模型开发重点是吞噬细胞骨髓谱系清除凋亡物质的缺陷。尽管骨髓缺陷可能会导致疾病风险，我们假设平行的 B 细胞内在机制 NCF1 和 NCF2 变异体携带者患 SLE 的风险显着增加。除了产生致病性自身抗体，最近的研究表明 B 细胞可以促进狼疮通过启动免疫耐受中断并促进自发生发的产生来发病机制中心（GC）。 SLE 中自身反应性 B 细胞的激活需要 B 细胞内在表达内体 Toll 样受体 TLR7 和 TLR9，我们发表的初步数据表明，NOX2 活性降低通过影响非规范自噬途径导致内体 TLR 信号失调。基于根据这些数据，我们假设 B 细胞特异性降低 NOX2 活性将导致 TLR- 依赖GC的形成和体液自身免疫的发展。我们将通过体内平行测试这个想法和体外机制研究。在目标1中，我们将测试B细胞内源性缺失NOX2组成基因是否使用特征良好的病毒感染模型增强 TLR 依赖性 GC 反应。在目标 2 中，我们将研究NOX2活性降低是否会促进自身抗体的产生和体液自身免疫小鼠 SLE。最后，在目标 3 中，我们将使用生化和细胞成像方法来测试 NAPDH 是否氧化酶活性影响 B 细胞 TLR 信号传导和使用小鼠遗传的非典型自噬途径模型和基因编辑的人类 B 细胞。这些研究共同有望增进我们对狼疮的了解发病机制，并可能为未来人类系统性红斑狼疮靶向治疗的设计提供信息。