Mechanisms and Modulation of Accelerated Atherosclerosis in Clonal Hematopoiesis

克隆造血加速动脉粥样硬化的机制和调节

• 批准号: 10590675
• 负责人: Peter Libby
• 金额: $ 65.04万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2026-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10590675
• 关键词: Ablation; Acceleration; Age; Aging; Antibodies; Arterial Fatty Streak; Atherosclerosis; Biology; Blood; Bone Marrow; Bone Marrow Cells; Bone Marrow Stem Cell; Cardiovascular system; Cells; Chimera organism; Chimeric Proteins; Clinical; Clinical Data; DNMT3a; Data; Endothelium; Etiology; Event; Evolution; Female; Genotype; Gonadal Steroid Hormones; Hematopoiesis; Host Defense; Human; IL-6 inhibitor; IL6ST gene; IgG1; In Situ; Individual; Infection; Inflammasome; Inflammation; Inflammatory; Interleukin 6 Receptor; Interleukin-1; Interleukin-1 beta; Interleukin-6; Interleukins; Interruption; Lesion; Leukocytes; LoxP-flanked allele; Macrophage; Mediator; Messenger RNA; Monitor; Mononuclear; Mus; Mutation; Myelogenous; Myeloid Cells; Oncology; Organ; Outcome; PTPRC gene; Pathway interactions; Phagocytes; Population; Procedures; Proteins; Recurrence; Research; Risk; Risk Factors; Role; Science; Sex Differences; Signal Transduction; Smooth Muscle Myocytes; Somatic Mutation; Spleen; Testing; Work; atherogenesis; atherothrombosis; cardiovascular risk factor; clinical investigation; cytokine; experience; experimental study; genetic variant; improved; infection risk; interleukin-6 receptor alpha; male; mutant; novel; peripheral blood; preservation; response; single-cell RNA sequencing; targeted treatment; translational potential

Project Summary/Abstract With age, humans can accumulate leukocyte clones in blood that arise from somatic mutations in bone marrow stem cells that enhance expansion: clonal hematopoiesis of indeterminate potential (CHIP). Mutations in DNMT3A and TET2 account for the plurality of these clones. CHIP confers highly elevated cardiovascular (CV) risk, independent of traditional risk factors. We have found accelerated atherogenesis and the involvement of IL-1 and IL-6 in mice with myeloid loss of Tet2 or Dnmt3a function and that genetically reduced IL-6 signaling abrogates the elevated CV risk in humans with DNMT3A or TET2 CHIP. Analyses of our CANTOS trial showed greater efficacy of IL-1β inhibition in humans with DNMT3A or TET2 CHIP. These results point the way to a genotype-directed allocation of therapy, an approach that has transformed oncology but remains aspirational in atherosclerosis. The roles of classical vs. trans IL-6 signaling in atherothrombosis requires further study due to conflicting evidence. Specific aim 1 will test the hypothesis that atherosclerotic mice that mimic CHIP due to myeloid deficiency in Dnmt3a treated with an antibody that interrupts global IL-6 signaling by neutralizing IL-6 receptor α (IL-6r, CD126) have decreased atherosclerosis and inflammation within the lesions, blood and other organs as gauged in part by single-cell RNA sequencing (scRNA-seq). We further hypothesize that IL-6r inhibition will limit expansion of the mutant clone. Specific aim 2 will probe the role of classical vs. trans IL-6 signaling in myeloid cells in accelerated atherogenesis in CHIP using Il6rflox/flox/Lyz2-Cre mice bone marrow chimeric LDLR-/- mice (to block leukocyte classical signaling), and administration of a gp130-IgG1-Fc chimeric protein (to block trans signaling) using similar procedures and endpoints. The results will illuminate the controversy and unsettled science regarding the contributions of classical and trans IL-6 signaling to atherogenesis. Specific aim 3. Our preliminary experiments show that female myeloidTet2-/-Ldlr-/- mice have greater acceleration of atherogenesis than Tet2+/+ Ldlr-/- male mice and, unlike their male counterparts, show reduced atherogenesis with IL-1β neutralization. We will localize where this sex difference operates in the inflammasome–IL-1β–IL-6 pathway, and test the hypothesis that female Dnmt3a-/-Ldlr-/- mice have greater response to IL-6r inhibition than males. We will probe mechanisms by gonadal ablation experiments and by analysis of scRNA-seq data, which in preliminary data shows IL-1β expression in resident macrophages cells from atheroma from Tet2-/- females but not males. This work will deepen understanding of the mechanisms of accelerated atherosclerosis in CHIP. Our new pilot clinical data show that an anti-IL-6 antibody can mute inflammation in humans. Thus, the work proposed here will provide an indispensable step toward validating and furnishing the fundamental basis of an immediately translatable targeted therapeutic strategy based on CHIP genotype.

项目概要/摘要 随着年龄的增长，人类可以在血液中积累由骨髓体细胞突变产生的白细胞克隆 增强扩增的干细胞：不确定潜力的克隆造血（CHIP）。突变在 DNMT3A 和TET2 解释了这些克隆的多个。 CHIP 显着提高心血管 (CV) 风险，独立于传统风险因素。我们发现动脉粥样硬化加速发生并参与 Tet2 或 Dnmt3a 功能骨髓缺失且 IL-6 信号传导基因降低的小鼠中的 IL-1 和 IL-6 使用 DNMT3A 或 TET2 芯片消除人类升高的 CV 风险。我们的 CANTOS 试验分析表明 使用 DNMT3A 或 TET2 CHIP 对人类进行 IL-1β 抑制效果更佳。这些结果指明了道路 基因型导向的治疗分配，这种方法已经改变了肿瘤学，但仍然是人们所渴望的 动脉粥样硬化。经典与反式 IL-6 信号传导在动脉粥样硬化血栓形成中的作用需要进一步研究，因为 相互矛盾的证据。具体目标 1 将检验以下假设：模拟 CHIP 的动脉粥样硬化小鼠由于 用抗体治疗 Dnmt3a 的骨髓缺陷，该抗体通过中和 IL-6 来中断整体 IL-6 信号传导 受体α（IL-6r、CD126）具有减少动脉粥样硬化和病变内炎症、血液和其他 部分通过单细胞 RNA 测序 (scRNA-seq) 来测量器官。我们进一步假设 IL-6r 抑制将限制突变克隆的扩展。具体目标 2 将探讨经典 IL-6 与反式 IL-6 的作用 使用 Il6rflox/flox/Lyz2-Cre 小鼠骨髓在 CHIP 中加速动脉粥样硬化形成中骨髓细胞的信号传导 嵌合 LDLR-/- 小鼠（阻断白细胞经典信号传导），并给予 gp130-IgG1-Fc 嵌合体 使用类似的程序和终点来检测蛋白质（以阻断反式信号传导）。结果将阐明 关于经典和反式 IL-6 信号转导对 动脉粥样硬化。具体目标3.我们的初步实验表明雌性骨髓Tet2-/-Ldlr-/-小鼠具有 与 Tet2+/+ Ldlr-/- 雄性小鼠相比，动脉粥样硬化形成加速更快，并且与雄性小鼠不同，显示 通过 IL-1β 中和减少动脉粥样硬化形成。我们将定位这种性别差异在哪些地方发挥作用 炎症体–IL-1β–IL-6通路，并检验雌性 Dnmt3a-/-Ldlr-/- 小鼠具有更大的 对 IL-6r 抑制的反应高于男性。我们将通过性腺消融实验和 scRNA-seq 数据分析，初步数据显示常驻巨噬细胞中的 IL-1β 表达 来自 Tet2-/- 女性而非男性的动脉粥样硬化。这项工作将加深对机制的理解 CHIP 加速动脉粥样硬化。我们新的试点临床数据表明，抗 IL-6 抗体可以使 人体炎症。因此，这里提出的工作将为验证 并为基于的可立即转化的靶向治疗策略提供基础基础 CHIP 基因型。