Therapeutic Targets in Acute Chest Syndrome

急性胸部综合症的治疗目标

• 批准号: 10565873
• 负责人: Solomon Fiifi Ofori-Acquah
• 金额: $ 68.95万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-07 至 2026-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10565873
• 关键词: Acute; Acute Lung Injury; Adult; Africa; African; Age; Azacitidine; Biological; Blood; Blood Cells; Blood Circulation; Cells; Cessation of life; Child; Clinical; Complication; CpG Islands; DNA Methylation; DNA Sequence; Data; Dose; Enrollment; Enzymes; Epigenetic Process; Genes; Genetic; Genetic Diseases; Genomics; Ghana; HL60; Health; Heme; Hemolysis; Human; Individual; Inflammatory; Infusion procedures; Iron; Knock-out; Liver; Longitudinal cohort; Lung; Measures; Messenger RNA; Methylation; MicroRNAs; Modeling; Molecular; Mus; Organ; Outcome; Pathogenesis; Patients; Peripheral Blood Mononuclear Cell; Pilot Projects; Plasma; Population; Pre-Clinical Model; Pregnant Women; Process; Production; Proteins; Recombinants; Reporting; Research; Respiratory distress; Risk; Role; Sampling; Sickle Cell Anemia; Signal Transduction; Site; Stress; Survival Rate; TLR4 gene; Testing; Therapeutic; Time; Toxic effect; Transgenic Mice; Transgenic Organisms; Variant; acute chest syndrome; cohort; conditional knockout; demethylation; design; efficacy testing; enzyme activity; experience; experimental study; extracellular; functional genomics; genome sequencing; genome-wide; heme oxygenase-1; improved; knock-down; mRNA Expression; next generation; next generation sequencing; novel; overexpression; premature; prevent; promoter; prophylactic; targeted treatment; therapeutic target; whole genome

SUMMARY This project is aimed at improving the health of individuals who have sickle cell disease (SCD) by defining a potential pro-survival factor of acute chest syndrome (ACS), and exploring whether this factor can be developed as a molecular therapeutic. ACS is the leading pulmonary complication and a common cause of premature death in SCD. There is no specific treatment for ACS despite decades of intensive research, and so it continues to be a major clinical problem in SCD, particularly, in Africa. We recently discovered that extracellular heme triggers ACS in an inflammatory process involving toll-like receptor 4 signaling. A growing number of experimental, clinical and genomics studies support this model of ACS pathogenesis in which extracellular heme triggers the acute lung injury. In this new R01 project, we test the novel idea that children express supra-physiological levels of heme oxygenase-1 (HO-1), the rate-limiting heme degradation enzyme. We posit that the high-level HO-1 in children enhances their ability to clear excess heme from the blood circulation to improve their overall outcome from ACS. In pilot studies, we found that replenishing HO-1 in the plasma of adult SCD mice improved ACS survival. These prior research provide a strong rationale to understand how endogenous HO-1 production is regulated in SCD, and to test whether a recombinant HO-1 will be efficacious in treating ACS in a preclinical model. Thus, in Aim #1, we will quantify blood HO-1 expression in patients and transgenic mice with SCD, and examine whether HO-1 expression in peripheral blood mononuclear cells is influenced by miR-494 expression and methylation of a highly conserved CpG site in HMOX1 the HO-1 gene. We will over-express and knock- down miR-494 in human peripheral blood mononuclear cells, and knock-out HO-1 activity in peripheral blood mononuclear cells of transgenic SCD mice, to determine the direct effects of these genetic/epigenetic alterations on HO-1 concentration in the plasma. We will perform whole genome next generation sequencing of SCD children with extreme levels of blood HO-1 level to identify novel whole genome sequence (WGS) variants that influence activity of this enzyme independent of age, miR-494 and HMOX1 methylation. In Aim #2, we will study a large cohort of SCD patients in Ghana to assess for the first time whether baseline blood HO-1 level, miR-494 level, HMOX1 methylation and WGS variants influence ACS risk. In Aim #3, we will use functional genomics to test the importance of HO-1 expression in blood cells in improving ACS survival, and test the efficacy of a novel truncated recombinant HO-1 molecule to rescue transgenic SCD mice from ACS. Data from this project has the potential to fundamentally change our understanding of how the body naturalizes the danger posed by circulating heme on organ function. In addition, it may provide a mechanism to explain the markedly variable ACS outcome in children and adults, with a tangible therapeutic strategy that can be implemented expeditiously using our novel HO-1 biologic.

概括 该项目旨在通过定义一个 急性胸部综合征（ACS）的潜在促生存因子，并探索是否可以开发该因子 作为分子治疗。 ACS是主要的肺并发症，也是过早死亡的常见原因 在SCD中。尽管进行了数十年的深入研究，但仍未针对ACS进行具体处理，因此它仍然是 SCD中的一个主要临床问题，特别是在非洲。我们最近发现细胞外血红素触发器 在涉及Toll样受体4信号传导的炎症过程中的ACS。越来越多的实验 临床和基因组学研究支持这种ACS发病机理，其中细胞外血红素触发了 急性肺损伤。在这个新的R01项目中，我们测试了儿童表达超生理水平的新颖想法 血红素氧酶-1（HO-1），限速血红素降解酶。我们认为高级HO-1在 儿童增强了从血液循环中清除过量血红素以改善其整体结果的能力 来自ACS。在试点研究中，我们发现在成年SCD小鼠的血浆中补充HO-1改善了ACS 生存。这些先前的研究为了解内源性HO-1产生的生产提供了有力的理由 在SCD中调节，并测试重组HO-1是否有效地治疗临床前的AC 模型。因此，在AIM＃1中，我们将用SCD量化患者和转基因小鼠的血液HO-1表达，以及 检查外周血单核细胞中的HO-1表达是否受miR-494表达的影响 HMOX1中高度保守的CpG位点的甲基化HO-1基因。我们将过分表达和敲门 在人外周血单核细胞中向下miR-494，并在外周血中敲除HO-1活性 转基因SCD小鼠的单核细胞，以确定这些遗传/表观遗传学改变的直接作用 在血浆中的HO-1浓度上。我们将执行SCD的整个基因组下一代测序 血液HO-1水平极高的儿童识别新型的全基因组序列（WGS）变体 影响这种酶的活性，与年龄，miR-494和HMOX1甲基化无关。在AIM＃2中，我们将学习 加纳的大量SCD患者首次评估基线血液HO-1水平，miR-494 水平，HMOX1甲基化和WGS变体会影响ACS风险。在AIM＃3中，我们将使用功能基因组学来 测试HO-1表达在血液细胞改善AC的存活中的重要性，并测试新型的功效 截短的重组HO-1分子从AC中拯救了转基因SCD小鼠。该项目的数据具有 从根本上改变我们对人体如何自然化造成危险的潜力 血红素的器官功能。此外，它可能提供一种解释明显变化AC结果的机制 在儿童和成人中，具有切实的治疗策略，可以使用我们的小说来迅速实施 HO-1生物学。