Cellular Sources of Self Antigen in SLE

SLE 自身抗原的细胞来源

基本信息

批准号：
10265341
负责人：
DAVID STEPHEN PISETSKY
金额：
--
依托单位：
DURHAM VA MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-01-01 至 2022-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10265341
关键词：
Acetaminophen Address Affect Alpha Particles Anti-DNA Antibodies Antibodies Antibody Specificity Antigen-Antibody Complex Antinuclear Antibodies Apoptosis Appearance Attention Autoantigens Autoimmune Diseases Autoimmunity Bacteria Binding Biochemical Biological Assay Biological Markers Blood Cell Death Cell Line Cells Cessation of life Clinical Research Complex Complication Confocal Microscopy DNA Data Dendritic Cells Deposition Development Diagnosis Disease Electrons Extracellular Space Flow Cytometry Galactosamine Generations Guanosine Health Immune Immune response Immune system Immunologics Immunosuppressive Agents Impairment In Vitro Infection Inflammation Inflammatory Interferons Kidney Lupus Lymphoid Cell Malignant Neoplasms Mediating Membrane Metabolism Mitochondria Mitochondrial DNA Molecular Monoclonal Antibodies Mus Myeloid Cells Nature Nephritis Nuclear Outcome Pain Particulate Pathogenesis Pathogenicity Patients Production Prognosis Property Quality of life Research Scanning Electron Microscopy Serology Source Structure System Systemic Lupus Erythematosus Techniques Tissues Toxic effect Uncertainty Veterans Woman Work cell injury cellular imaging cytokine disability experimental study extracellular in vivo in vivo Model insight macromolecule military veteran mouse model new therapeutic target novel marker novel strategies oxidation particle sensor vesicular release

项目摘要

Abstract Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease characterized by the production of antinuclear antibodies (ANAs) in association with severe multisystem inflammatory disease manifestations. ANAs target a wide array of nuclear macromolecules and can mediate disease by the formation of immune complexes that deposit in the tissue to promote inflammation and damage; these complexes can also stimulate the production of cytokines including type 1 interferon to drive generalized immune system disturbances. Among ANAs forming immune complexes, antibodies to DNA (anti-DNA) are the serological hallmark of SLE and markers of diagnosis and prognosis. These antibodies bind to both single and double stranded DNA and form immune complexes that deposit in the tissue, especially the kidney, to promote inflammation; in addition, these immune complexes can stimulate the production of cytokines by plasmacytoid dendritic cells, triggering internal sensors of DNA. While the properties of anti-DNA antibodies have been extensively studied, much less is known about the origin of antigenic DNA, its access to the immune system and its unique molecular properties. In general, the source of this DNA has been considered to be nuclear in origin and the product of dead and dying cells. Our studies have provided a new perspective on this issue by demonstrating two important features of extracellular DNA: 1) its existence in the form of microparticles and 2) the presence in these particles of mitochondrial (mt) as well as nuclear DNA (nDNA). This presence of mtDNA is important since mtDNA is intrinsically immunostimulatory because of structural features that differ from those of nDNA. These involve CpG motifs in mtDNA, a consequence of the origin of mitochondria from bacteria, and oxidation of guanosine residues. Furthermore, we have shown that mitochondria released from cells have properties similar to those of microparticles, suggesting that mitochondria may serve as self-antigens in lupus, contributing to immune activities attributed to microparticles and providing a nidus for immune complex formation. Building on preliminary work, the proposed studies will focus on three main hypotheses: 1) DNA autoantigen can be released from cells undergoing various death forms and exist in both a free and particle form; 2) the metabolism of DNA during cell death influences the amount in the blood, its size and its representation in particle or soluble form; and 3) anti-DNA antibodies can bind to various antigenic forms of DNA, both free and particulate, with assay of antibodies to these forms providing more informative biomarkers. We will pursue three specific aims. Specific Aim 1: To determine the extracellular release of cellular DNA during different forms of in vitro cell death. We will induce different forms of cell death in cell lines in vitro and determine the representation of mtDNA and nDNA in soluble and particulate forms; Specific Aim 2. To use in vivo models to elucidate the release of DNA into the blood. We will use in vivo systems in the mouse to explore the release of mtDNA and nDNA following cell death; we will also sequence DNA in the blood by high throughput techniques; and Specific Aim 3: Using blood from patients with lupus and murine models, we will determine the presence and specificity of antibodies to various sources of extracellular DNA in SLE. To develop new serological approaches, we will determine the presence and specificity of antibodies to different antigenic forms of DNA, both free and particulate and, by assessing results from a large panel of well characterized patients, develop new biomarkers. Successful completion of these experiments will provide new insights into the mechanisms of pathogenicity as well as provide new biomarkers for clinical and research purposes.

抽象的系统性红斑狼疮 (SLE) 是一种典型的自身免疫性疾病，其特征是产生抗核抗体（ANA）与严重的多系统炎症性疾病表现相关。 ANA 靶向多种核大分子，可通过形成免疫细胞介导疾病沉积在组织中促进炎症和损伤的复合物；这些复合物还可以刺激产生包括 1 型干扰素在内的细胞因子，以驱动全身免疫系统紊乱。在形成免疫复合物的 ANA 中，DNA 抗体（抗 DNA）是 SLE 的血清学标志以及诊断和预后的标志物。这些抗体可结合单链和双链 DNA，形成免疫复合物沉积在组织中，尤其是肾脏中，从而促进炎症；此外，这些免疫复合物可以刺激浆细胞样树突状细胞产生细胞因子，引发 DNA 的内部传感器。虽然抗 DNA 抗体的特性已被广泛研究，但许多关于抗原 DNA 的起源、它进入免疫系统的途径及其独特的分子，人们知之甚少。特性。一般来说，这种 DNA 的来源被认为是核起源的，并且是死亡和垂死的细胞。我们的研究通过证明两个方面为这个问题提供了新的视角细胞外 DNA 的重要特征：1) 它以微粒的形式存在，2) 存在于这些线粒体 (mt) 和核 DNA (nDNA) 颗粒。线粒体 DNA 的存在很重要由于 mtDNA 的结构特征与 nDNA 不同，因此本质上具有免疫刺激作用。这些涉及 mtDNA 中的 CpG 基序（这是细菌线粒体起源的结果）和氧化作用鸟苷残基。此外，我们已经证明从细胞释放的线粒体具有以下特性：与微粒相似，表明线粒体可能作为狼疮的自身抗原，促进微粒的免疫活动并为免疫复合物提供巢穴形成。在前期工作的基础上，拟议的研究将重点关注三个主要假设：1）DNA 自身抗原可以从经历各种死亡形式的细胞中释放出来，并以游离和颗粒形式存在形式; 2）细胞死亡过程中DNA的代谢影响血液中的DNA量、大小及其以颗粒或可溶形式表示； 3）抗DNA抗体可以结合多种抗原形式 DNA，无论是游离的还是颗粒的，通过对这些形式的抗体进行分析，可以提供更多信息的生物标志物。我们将追求三个具体目标。具体目标 1：确定细胞 DNA 的胞外释放在不同形式的体外细胞死亡期间。我们将在体外诱导细胞系中不同形式的细胞死亡，确定 mtDNA 和 nDNA 在可溶性和颗粒形式中的表示；具体目标 2. 用于体内模型阐明 DNA 释放到血液中。我们将使用小鼠体内系统探索细胞死亡后 mtDNA 和 nDNA 的释放；我们还将通过高通量测序血液中的 DNA 吞吐量技术；具体目标 3：使用狼疮患者和小鼠模型的血液，我们将确定 SLE 中针对不同来源的细胞外 DNA 的抗体的存在和特异性。到开发新的血清学方法，我们将确定不同抗体的存在和特异性 DNA 的抗原形式，包括游离的和颗粒的，并且通过评估大量孔板的结果表征患者，开发新的生物标志物。这些实验的成功完成将提供新的深入了解致病机制并为临床和研究提供新的生物标志物目的。