miR-21 regulation of autoreactive B cell and lupus nephritis development

miR-21对自身反应性B细胞和狼疮性肾炎发展的调节

• 批准号: 10888833
• 负责人: Ziaur Rahman
• 金额: $ 54.37万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-18 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10888833
• 关键词: Affect; American; Antibodies; Asthma; Attenuated; Autoantibodies; Autoimmune; Autoimmune Responses; Autoimmunity; Automobile Driving; B-Cell Activation; B-Lymphocytes; Binding Sites; Bone Marrow; Cells; Cellular Metabolic Process; Cre lox recombination system; Data; Development; Disease; Disease Progression; Exhibits; Experimental Autoimmune Encephalomyelitis; FRAP1 gene; Gene Expression; Genes; Grant; Helper-Inducer T-Lymphocyte; Human; Immune; Immunity; Inflammatory; Interferon Type I; Knowledge; Learning; Ligands; Lupus Nephritis; Malignant Neoplasms; Mediating; Metabolic; Metabolic Pathway; Metabolism; MicroRNAs; Modeling; Mus; NF-kappa B; Oligonucleotides; Onset of illness; Oxygen Consumption; PIK3CG gene; Pathway interactions; Patients; Persons; Phenotype; Plasma Cells; Production; Promoter Regions; Regulation; Regulator Genes; Role; Signal Pathway; Signal Transduction; Structure of germinal center of lymph node; Systemic Lupus Erythematosus; TLR7 gene; Tamoxifen; Testing; autoreactive B cell; comparison control; extracellular; human model; inducible Cre; mouse model; mutant; overexpression; posttranscriptional; response; systemic autoimmunity; targeted treatment; therapeutic target; transcription factor; transcriptome sequencing

Project Summary MicroRNAs (miRNAs) are critical post-transcriptional regulators of gene expression in immunity and autoimmunity, although many miRNAs remain poorly characterized. One such miRNA, miRNA-21 (miR-21), is upregulated in systemic lupus erythematosus (SLE) patients and promotes various diseases in mouse models. These include experimental autoimmune encephalomyelitis (EAE), asthma, cancer, and our findings on its role in toll-like receptor 7 (TLR7)-driven SLE in mice. We found that TLR7 overexpressing SLE-prone B6.Sle1bYaa mice deficient in miR-21 (Sle1bYaamiR-21-/-) had reduced germinal center (GC) B cell, T follicular helper (Tfh) cell and plasma cell (PC) responses. These responses in Sle1bYaamiR-21-/- mice were strongly associated with reduced autoantibody, and splenic and bone marrow autoantibody-producing antibody forming cell (AFC) responses. These data substantiate a role for miR-21 in the loss of B cell tolerance and autoimmunity, which necessitates identification of mechanisms (focus of the grant) by which miR-21 promotes autoantibody production and SLE. This will fill gaps in knowledge and may help discover an urgently needed targeted therapy for SLE, a debilitating disease that affects millions of Americans and people world-wide. TLR signaling, especially TLR7, promotes SLE in humans and murine models, and an attractive therapeutic target. TLR7 signaling activates the NF-kB inflammatory signaling pathway. TLR7 upregulates miR-21 expression in B cells which can target the negative regulator of NF-kB signaling, Peli1, although the role of miR-21 in regulating NF- kB signaling in SLE-prone B cells by targeting Peli1 is unknown. Preliminary data showed that B cells from Sle1bYaamiR-21-/- mice have increased Peli1 expression compared to control Sle1bYaa B cells. In addition, previous studies implicated TLR signaling in metabolic reprogramming, primarily through the activation of the PI3K/Akt/mTOR pathway in various immune conditions, although the role of this pathway in TLR7-mediated metabolic reprograming in B cells in SLE is not clear. miR-21 was also shown to regulate the PI3K/Akt/mTOR pathway in various models; however, its role in regulating B cell metabolism in TLR7-driven SLE is not known. Interestingly, our RNA-seq analysis of B cells from a TLR7-induced model showed negatively enriched genes in the PI3K/Akt/mTOR pathway in the absence of miR-21. Additional preliminary data showed increased extracellular acidification (ECAR) and oxygen consumption (OCR) rates in Sle1bYaa B cells overexpressing TLR7 compared to Sle1b B cells, indicating a more energetic phenotype in response to TLR7 signaling. Conversely, Sle1bYaamiR-21-/- B cells exhibited reduced ECAR and OCR compared to Sle1bYaa B cells. We hypothesize that miR-21 promotes TLR7-driven systemic autoimmune responses and SLE disease by regulating TLR7-NF-kB signaling and metabolic reprogramming in B cells. Proposed hypothesis and specific aims will help delineate the mechanism by which miR-21 drives autoimmune responses and lupus nephritis and will inform us whether miR-21 or miR-21 regulated pathway(s) can be a therapeutic target for SLE.

项目摘要 微小RNA（miRNAs）是免疫中基因表达的关键转录后调节因子， 自身免疫，尽管许多miRNAs仍然缺乏特征。一种这样的miRNA，miRNA-21（miR-21）， 在系统性红斑狼疮（SLE）患者中上调，并在小鼠模型中促进各种疾病。 这些包括实验性自身免疫性脑脊髓炎（EAE），哮喘，癌症，以及我们对它的作用的研究结果 Toll样受体7（TLR 7）驱动的SLE小鼠。我们发现TLR 7过表达SLE易感B6.Sle1bYaa miR-21缺陷小鼠（Sle 1bYaamiR-21-/-）的生殖中心（GC）B细胞、滤泡辅助T细胞（Tfh） 细胞和浆细胞（PC）反应。Sle 1bYaamiR-21-/-小鼠的这些反应与以下因素密切相关： 自身抗体减少，脾和骨髓产生自身抗体的抗体形成细胞（AFC） 应答这些数据证实了miR-21在B细胞耐受性和自身免疫性丧失中的作用， 需要确定miR-21促进自身抗体的机制（资助的重点） 生产和SLE。这将填补知识空白，并可能有助于发现迫切需要的有针对性的 SLE是一种使人衰弱的疾病，影响数百万美国人和世界各地的人们。TLR信号， 特别是TLR 7，在人和鼠模型中促进SLE，并且是有吸引力的治疗靶点。TLR7 信号传导激活NF-κ B炎症信号传导途径。TLR 7上调B细胞中miR-21的表达 它可以靶向NF-kB信号传导的负调节因子Peli 1，尽管miR-21在调节NF-κ B信号传导中的作用是不确定的。 目前尚不清楚通过靶向Peli 1在狼疮易感性B细胞中进行的kB信号传导。初步数据显示，B 与对照Sle 1bYaa B细胞相比，Sle 1bYaamiR-21-/-小鼠具有增加的Peli 1表达。此外，本发明还提供了一种方法， 先前的研究表明TLR信号传导参与代谢重编程，主要是通过激活 PI 3 K/Akt/mTOR通路在各种免疫条件下的作用，尽管该通路在TLR 7介导的免疫应答中的作用已经被证实。 SLE中B细胞的代谢重编程尚不清楚。miR-21还显示调节PI 3 K/Akt/mTOR 然而，其在调节TLR 7驱动的SLE中的B细胞代谢中的作用尚不清楚。 有趣的是，我们对来自TLR 7诱导模型的B细胞的RNA-seq分析显示负富集基因 在不存在miR-21的情况下，PI 3 K/Akt/mTOR通路中。初步数据显示， 过表达的Sle 1bYaa B细胞中的细胞外酸化（ECAR）和耗氧（OCR）速率 TLR 7与Sle 1 B B细胞相比，表明响应TLR 7信号传导的更有活力的表型。 相反，与Sle 1bYaa B细胞相比，Sle 1bYaamiR-21-/- B细胞表现出降低的ECAR和OCR。我们 假设miR-21通过以下方式促进TLR 7驱动的系统性自身免疫应答和SLE疾病： 调节B细胞中的TLR 7-NF-kB信号传导和代谢重编程。提出的假设和具体 目的将有助于阐明miR-21驱动自身免疫反应和狼疮性肾炎的机制， 并将告知我们miR-21或miR-21调节的通路是否可以成为SLE的治疗靶点。