Intrinsic B cell epigenetic regulation of antibody and autoantibody responses by Sirt1

Sirt1 对抗体和自身抗体反应的内在 B 细胞表观遗传调控

基本信息

批准号：
10335163
负责人：
Paolo Casali
金额：
$ 47.44万
依托单位：
UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-06-14 至 2024-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10335163
关键词：
3&apos Untranslated Regions ATAC-seq Address Aftercare Aging Allergens Animal Model Antibodies Antibody Response Antigens Autoantibodies Autoantigens Autoimmune Diseases Autoimmunity B cell differentiation B-Cell Activation B-Lymphocytes Back Bacteria Biochemistry Biosensor Cell physiology Cellular biology ChIP-seq Cues DNA Methylation DNA Modification Methylases Data Deacetylation Dependence Development Diabetes Mellitus Dietary Fiber Down-Regulation Elements Epigenetic Process Gene Activation Gene Expression Genes Genetic Genetic Predisposition to Disease Genetic Recombination Genetic Transcription Genome Glucose Goals Grant Histone Deacetylase Histone Deacetylase Inhibitor Histone Deacetylation Histone H3 Histones Homeostasis Human IgG autoantibodies Image Immunoglobulin Class Switching Immunoglobulin Somatic Hypermutation Immunoglobulins In Vitro Inbred MRL lpr Mice Internal Ribosome Entry Site Luciferases Lupus MYB gene Malignant Neoplasms Mediating Mediator of activation protein Memory Memory B-Lymphocyte Metabolic MicroRNAs Modification Molecular Mouse Strains Mus Mutate NF-kappa B Patients Phase Plasma Cells Post-Translational Protein Processing Pristane Process Regulation Reporter Rest Role SIRT1 gene SLEB1 gene Signal Pathway Sirtuins Supplementation Testing Therapeutic Transcription Coactivator Transcription Repressor USF1 gene Untranslated RNA Up-Regulation Virus Volatile Fatty Acids Water activation-induced cytidine deaminase animal imaging cell type cofactor demethylation ds-DNA epigenetic regulation experimental study gut microbiota human model humanized mouse immunoregulation in vivo innovation insight nicotinamide-beta-riboside non-histone protein novel novel therapeutics organ injury overexpression programs promoter response sensor small molecule stem systemic autoimmunity therapeutic target tissue injury tool transcriptome sequencing

项目摘要

PROJECT SUMMARY We want to unveil novel fundamental B cell-intrinsic epigenetic mechanisms that maintain B cell homeostasis and inform B cell processes critical to the antibody response to exogenous antigens (e.g., viruses, bacteria) and self-antigens (e.g., dsDNA, RNPs in systemic lupus). As we have shown in the first cycle of this grant, epigenetic mechanisms interact with genetic programs to modulate AID (encoded by AICDA/Aicda) expression, critical for SHM/CSR. Indeed, Zn2+-dependent Class I, II and IV HDACs promote AID induction and SHM/CSR in a B cell-intrinsic fashion. AID induction is dampened by Class I, II and IV HDAC inhibitors, such as short- chain fatty acids produced by gut microbiota via processing of dietary fibers, through upregulation of select microRNAs that target AICDA/Aicda 3’UTR, leading to abrogation of antibody/autoantibody responses. Prompted by our most recent and compelling findings on Sirt1, a NAD+-dependent Class III HDAC and metabolic sensor implicated in aging, cancer and diabetes, we hypothesize that this Sirtuin dampens AID (a role opposite to that of Class I, II and IV HDACs) in a B cell-intrinsic fashion, and regulation of Sirt1 expression or activity effectively modulates SHM/CSR and antibody/autoantibody responses. As we contend, high Sirt1 levels/activity would effect homeostatic Aicda silencing in resting B cells, the first phase of a tri-phasic fluctuation of reciprocal Sirt1 and AID expression, as followed by low Sirt1 and high AID in activated B cells and back to high Sirt1 to low AID in plasma cells and memory B cells. Sirt1 would modulate AID expression through a three-prong histone and non-histone protein deacetylation. It would also enforce a B cell-intrinsic metabolic–epigenetic checkpoint of AID upregulation since Sirt1 cofactor NAD+ integrates metabolic cues. Our strengths in B cell biology, molecular SHM/CSR mechanisms and autoimmunity, as well as our cutting- edge epigenetic approaches (ChIP-Seq, methylDNA-Seq and ATAC-Seq), new tools in biochemistry (NAD+ biosensor), genetics (Cd19+/Cre-Ert2Sirt16fl/flRosa26fl-STOP-fl-tdTomato and Cd19+/Cre-Ert2Rosa26fl-STOP-fl-Sirt1-IRES-Gfp mice), imaging (AicdaCreRosa26fl-STOP-fl-luciferase reporter mice), and animal models of human antibody/autoantibody responses (humanized NSG/cKitW-41J mice) make us uniquely poised to test our hypotheses. Aim1 addresses human and mouse B cell differentiation stage-specific regulation of Sirt1 expression and NAD+ levels, and underlying mechanisms, with focus on transcription activator USF1, transcription repressor c-Myb and microRNAs targeting Sirt1 3’UTR. Aim 2 addresses B cell Sirt1 role in dampening AICDA/Aicda expression through genetics and/or compounds/metabolites, and defines underlying H3K4Ac, H3K36Ac, Dnmt1 and NF- kB deacetylation mechanisms; Aim 3 addresses the inhibition of antibody and autoantibody responses by B cell Sirt1 and Sirt1 activators, and explores Sirt1 activators as therapeutics in systemic lupus. Our highly significant and innovative experiments will provide novel mechanistic insights into B cell epigenetics and immunoregulation, and yield metabolic-epigenetic checkpoint modulators as new therapeutics in autoimmunity.!

项目摘要我们想揭示保持B细胞稳态的新型基本B细胞内遗传机制并告知B细胞过程对抗体对外源抗原的反应至关重要（例如病毒，细菌）和自我抗原（例如，DSDNA，全身性狼疮中的RNP）。正如我们在这笔赠款的第一个周期中所显示的那样，表观遗传机制与遗传程序相互作用，以调节AID（由AICDA/AICDA编码）表达，对于SHM/CSR至关重要。实际上，Zn2+依赖性I类，II和IV HDAC促进辅助诱导和SHM/CSR 以B细胞中的方式。 I，II和IV HDAC抑制剂（例如短期）抑制了辅助诱导肠道菌群通过饮食纤维的加工而产生的链脂肪酸，通过上调靶向AICDA/AICDA 3'UTR的microRNA，导致抗体/自身抗体反应的废除。在SIRT1上的最新和引人入胜的发现，NAD+依赖性III级HDAC和在衰老，癌症和糖尿病中实施的代谢传感器，我们假设这种sirtuin抑制了援助（a 与I类，II和IV HDAC的角色相反，以B细胞中的方式进行调节，并调节SIRT1表达或活动有效调节SHM/CSR和抗体/自身抗体反应。正如我们认为，高sirt1 水平/活动将影响静止B细胞的体内平衡AICDA沉默，这是三倍的第一阶段互惠SIRT1和辅助表达的波动，其次是低SIRT1和激活的B细胞中的高辅助并回到高SIRT1，以低帮助浆细胞和记忆B细胞。 SIRT1将调节辅助表达通过三个prong的组蛋白和非历史蛋白脱乙酰化。它还将强制执行A B细胞中心 SIRT1辅因子NAD+集成的代谢线索以来，代谢 - 概念检查点。我们在B细胞生物学，分子SHM/CSR机制和自身免疫性方面的优势以及我们的剪裁边缘表观遗传学方法（chip-seq，methyldna-seq和atac-seq），生物化学的新工具（NAD+ 生物传感器），遗传学（CD19+/CRE-ERT2SIRT16FL/FLROSA26FL-Stop-Fl-TDTomato和CD19+/CRE-ERT2ROSA26FL-SIRT-FL-SIRT1-IRES-GFP小鼠），成像（aicdacrerosa26fl-stop-fl-luciferase Reporter小鼠）和人类抗体/自身抗体的动物模型反应（人源化的NSG/CKITW-41J小鼠）使我们被中毒以检验我们的假设。 AIM1地址人和小鼠B细胞分化的SIRT1表达和NAD+水平的特异性调节，以及基本机制，专注于转录激活剂USF1，转录复制级C-MYB和靶向SIRT1 3'UTR的microRNA。 AIM 2解决了B细胞SIRT1在DAMNADA AICDA/AICDA表达式中的作用通过遗传学和/或化合物/代谢物，并定义了基础H3K4AC，H3K36AC，DNMT1和NF- KB脱乙酰化机制； AIM 3解决了B对抗体和自身抗体反应的抑制细胞SIRT1和SIRT1激活剂，并探索SIRT1激活剂作为全身性狼疮的治疗。我们的高度重要而创新的实验将为B细胞表观遗传学和免疫调节，并产生代谢性概况检查点调节剂作为自身免疫性的新疗法。