Role of Aiolos in eosinophilic asthma

项目摘要 嗜酸性粒细胞(Eos)可在多种情况下从血液中重新聚集到组织中。 并导致预先形成和新合成的产物的释放，包括细胞因子、趋化因子、 脂质介体和细胞毒性颗粒蛋白，可启动并迅速升级局部 炎症和重塑反应。值得注意的是，嗜酸性粒细胞靶向治疗在 减少血液中成熟嗜酸性粒细胞的临床试验。然而，组织嗜酸性粒细胞增多症只是部分 抑制并可能是持续促进Eos招募和辅助途径的结果 生死存亡。残留的组织嗜酸性粒细胞增多会导致持续的症状和增加组织的风险。 嗜酸性粒细胞介导的疾病患者的损害。因此，设计的新疗法具有改进的 了解组织嗜酸性粒细胞增多症的机制是必要的，而且可能具有重要的临床意义。 冲击力。我们的初步研究表明，Aiolos是嗜酸性粒细胞中Eos积累的潜在调节因素 哮喘作为Aiolos缺乏导致对CCR3配体和IL-5的反应受损，IL-5是 嗜酸性哮喘的发病机制。这一提议的中心假设是Aiolos控制着呼吸道 哮喘嗜酸性粒细胞增多症的两个过程：1)直接调节Ccr3的表达 转录激活，以及2)涉及Aiolos、Il5ra和IL-5的正反馈环。在目标1中，我们将 鉴定Eos中依赖Aiolos的转录组并阐明Aiolos依赖的机制 CCR3的表达。我们还将确定Aiolos缺乏对Eos介导的组织的影响 实验性哮喘的病理学。在目标2中，我们将确定Aiolos介导的 通过评估Aiolos缺陷、单倍体功能不全和Aiolos缺陷的后果调节IL-5的反应性 EOPs、嗜酸性粒细胞前体(PreEos)和成熟Eos对IL-5的过度表达。我们 我还将剖析Eos过程中Aiolos表达、Il5ra表达和IL-5刺激之间的关系 在实验性哮喘背景下的发展。最后，在目标3中，我们将确定 Aiolos在人Eos中的表达水平以及1)特定的Eos基因信号，2)Eos对 IL-5和CCL11；3)哮喘病情严重程度和Eos表型。嗜酸性粒细胞增多症的高发 儿童哮喘的炎症和FDA最近批准IL-5靶向治疗嗜酸性哮喘 强调这一应用程序的意义，它重点描述了 Aiolos在Eos中的表达，Eos在炎症肺中的募集，以及Eos对IL-5的反应性。我们的建议 由翻译研究支持的使用小鼠和人类细胞系统的机械学研究(目标1和2 嗜酸性哮喘患者的Eos(AIM 3)将提供令人信服的证据来支持我们的中心 假设。我们研究的直接意义在于它有可能揭示一种剂量依赖关系 Aiolos在Eos中的表达与IL-5的应答之间的关系，这将为选择治疗方案提供理论依据 基于Eos表型的患者(例如，Aiolos表达水平)。

Project Summary Recruitment of eosinophils (Eos) from the bloodstream into tissues can occur under a variety of conditions and lead to the release of preformed and newly synthesized products, including cytokines, chemokines, lipid mediators and cytotoxic granule proteins, which can initiate and quickly escalate local inflammatory and remodeling responses. Notably, eosinophil-targeted therapy has been very effective in clinical trials at reducing mature eosinophils in the blood. However, tissue eosinophilia is only partially suppressed and likely results from accessory pathways that continue to promote Eos recruitment and survival. The residual tissue eosinophilia contributes to persistent symptoms and increased risk for tissue damage in patients with Eos-mediated diseases. Thus, new therapies designed with an improved understanding of the mechanism of tissue eosinophilia are needed and likely to have a significant clinical impact. Our preliminary studies implicate Aiolos as a potential regulator of Eos accumulation in eosinophilic asthma as Aiolos-deficiency results in impaired responses to CCR3 ligands and to IL-5, a key cytokine in the pathogenesis of eosinophilic asthma. The central hypothesis of this proposal is that Aiolos controls airway eosinophilia in asthma by two processes, 1) positive regulation of Ccr3 expression by direct transcriptional activation, and 2) a positive feedback loop involving Aiolos, Il5ra, and IL-5. In Aim 1, we will identify the Aiolos-dependent transcriptome in Eos and delineate the mechanism for Aiolos-dependent expression of CCR3. We will also determine the consequence of Aiolos deficiency on Eos-mediated tissue pathology in experimental asthma. In Aim 2, we will determine the mechanism for Aiolos-mediated regulation of IL-5-responsiveness by evaluating the consequence of Aiolos deficiency, haploinsufficiency and overexpression on stage-specific responses by EoPs, eosinophil precursors (preEos) and mature Eos to IL-5. We will also dissect the relationship between Aiolos expression, Il5ra expression and IL-5 stimulation during Eos development in the setting of experimental asthma. Finally, in Aim 3, we will determine the relationship between expression levels of Aiolos in human Eos and 1) a specific Eos gene signature, 2) functional response of Eos to IL-5 and CCL11, and 3) asthma disease severity and Eos phenotype. The high prevalence of eosinophilic inflammation in pediatric asthma and the recent FDA approval of IL-5-targeted therapy for eosinophilic asthma highlight the significance of this application which focuses on delineating the mechanistic relationship between Aiolos expression in Eos, Eos recruitment into the inflamed lung, and IL-5 responsiveness of Eos. Our proposed mechanistic studies using both mouse and human cell systems (Aims 1 and 2) supported by translational studies with Eos from patients with eosinophilic asthma (Aim 3) will provide compelling evidence to support our central hypothesis. The immediate significance of our study is its potential to uncover a dose-dependent relationship between Aiolos expression in Eos and response to IL-5 which would provide rationale for therapy selection for patients based on the Eos phenotype (e.g. Aiolos expression level).