Overcoming the Inhibitory Neurovascular Niche in Preterm Infant Brain Injury

克服早产儿脑损伤中的抑制性神经血管生态位

• 批准号: 10657221
• 负责人: MARK A PETERSEN
• 金额: $ 47.91万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-02-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10657221
• 关键词: Adult; Alzheimer' s Disease; Animal Model; Attenuated; Binding; Binding Sites; Blocking Antibodies; Blood - brain barrier anatomy; Blood Proteins; Blood Vessels; Blood coagulation; Bone Morphogenetic Proteins; Brain; Brain Injuries; Brain hemorrhage; Cell Maturation; Cells; Central Nervous System; Cerebellum; Cicatrix; Coagulation Process; Congenital cerebellar hypoplasia; Cytoplasmic Granules; Data; Deposition; Development; Developmental Disabilities; Disease; Environment; Fibrin; Fibrinogen; Fibrinogen Receptors; Functional disorder; Genetic; Goals; Growth; Hemorrhage; Human; ITGAM gene; ITGB2 gene; Impairment; Inflammation; Inflammatory; Injections; Injury; Innate Immune Response; Integrins; Knock-in Mouse; Link; Lipopolysaccharides; Macrophage; Microglia; Modeling; Molecular; Molecular Profiling; Monoclonal Antibodies; Multiple Sclerosis; Mutant Strains Mice; Mutate; Myelin; Natural regeneration; Neonatal; Nerve Degeneration; Neurodevelopmental Impairment; Neurons; Organoids; Outcome; Oxidative Stress; Pathway interactions; Plasma; Pluripotent Stem Cells; Population; Premature Infant; Proliferating; Proteins; Reactive Oxygen Species; Receptor Signaling; Risk; Role; Signal Transduction; Signaling Protein; Testing; Therapeutic; Trauma; Traumatic injury; Treatment Efficacy; Work; activin A; blood-brain barrier disruption; bone morphogenetic protein receptor type I; bone morphogenetic protein receptors; clinically relevant; defined contribution; disability; efficacy evaluation; human disease; immune activation; improved; in vivo; induced pluripotent stem cell; infant brain injury; inhibitor; neonatal mice; nerve stem cell; nervous system development; nervous system disorder; neurogenesis; neuroinflammation; neurovascular; novel; novel therapeutic intervention; pharmacologic; preservation; prevent; progenitor; receptor; remyelination; repaired; small molecule inhibitor; stem cells; systemic inflammatory response; transcriptomics

PROJECT SUMMARY/ABSTRACT Preterm infants are at risk for central nervous system (CNS) hemorrhage which can disrupt cerebellar maturation and lead to permanent neurodevelopmental impairment. The molecular signals in the disrupted neurovascular niche that block cerebellar development are not known. Thus, no therapeutics are available to prevent the developmental disabilities associated with preterm brain hemorrhage. Fibrinogen, a blood coagulation protein, crosses a leaky blood-brain barrier (BBB) and is a key driver of neuroinflammation, oxidative stress, neurodegeneration, glial scar formation, and inhibition of repair. We hypothesize that fibrinogen is a critical component of the neurovascular niche after BBB disruption that blocks cerebellar development in preterm infants. Our preliminary studies show: 1) Lipopolysaccharide (LPS)-induced systemic inflammation in neonatal mice increases vascular activation, fibrinogen deposition, and neuroinflammation in the cerebellum; 2) Fibrinogen depletion rescues cerebellar growth in systemic neonatal inflammation and plasma injection models of BBB disruption; 3) Fibrinogen inhibits neurogenesis from cerebellar granule neuronal progenitors (CGNPs) and is sufficient to disrupt cerebellar growth in vivo; 4) Fibrinogen activates the bone morphogenetic protein (BMP) receptor activin A receptor type I (ACVR1) in CNS progenitor cells to inhibit remyelination and neurogenesis; 5) Fibrin binds the CD11b/CD18 integrin receptor on microglia/macrophages to induce pro- inflammatory and pro-oxidant pathways that are toxic to CNS progenitor cells and impair regeneration; 6) fggγ390-396A knock-in mice, in which the binding site of fibrin to the CD11b integrin is mutated, have improved cerebellar growth during systemic neonatal inflammation. Our specific aims will test our working model, whereby fibrinogen deposition after BBB disruption alters cerebellar development through: 1) direct inhibitory effects on CGNPs via ACVR1 signaling, and 2) activation of innate immune responses via CD11b. In Aim 1, we will define the contribution of aberrant ACVR1 signaling to fibrinogen-induced cerebellar injury using CGNP-specific ACVR1 mutant mice and clinically relevant ACVR1 small molecule inhibitors. In Aim 2, we will determine the role of fibrin- CD11b-induced innate immune activation to cerebellar injury using fibrinogen mutant mice and a novel monoclonal antibody that blocks the interaction of fibrin with CD11b. In Aim 3, we will define how fibrinogen- ACVR1 signaling alters human cerebellar progenitor cell fate in induced pluripotent stem cell-derived cerebellar organoids using single cell transcriptomics. These studies will reveal molecular mechanisms at the neurovascular interface that link BBB disruption to CNS progenitor cell dysfunction in preterm infant brain injury. Thus, results from this proposal may open new treatment strategies to overcome the inhibitory neurovascular niche in preterm infant brain injury as well as other neurologic diseases with BBB disruption and fibrinogen deposition, such as multiple sclerosis, Alzheimer disease, and traumatic injury.

项目概要/摘要 早产儿有中枢神经系统 (CNS) 出血的风险，这可能会破坏小脑的成熟 并导致永久性神经发育障碍。受损神经血管中的分子信号 阻碍小脑发育的生态位尚不清楚。因此，目前尚无有效的治疗方法来预防 与早产脑出血相关的发育障碍。纤维蛋白原，一种凝血蛋白， 穿过渗漏血脑屏障 (BBB)，是神经炎症、氧化应激、 神经变性、神经胶质疤痕形成和修复抑制。我们假设纤维蛋白原是一个关键 BBB 破坏后神经血管生态位的组成部分，阻止早产儿小脑发育 婴儿。我们的初步研究表明：1）脂多糖（LPS）诱导的新生儿全身炎症 小鼠小脑血管活化、纤维蛋白原沉积和神经炎症增加； 2） 纤维蛋白原消耗可挽救全身新生儿炎症和血浆注射模型中的小脑生长 BBB 破坏； 3）纤维蛋白原抑制小脑颗粒神经元祖细胞（CGNP）的神经发生 并足以扰乱体内小脑的生长； 4) 纤维蛋白原激活骨形态发生蛋白 CNS 祖细胞中的 (BMP) 受体激活素 A 受体 I 型 (ACVR1) 可抑制髓鞘再生和 神经发生； 5) 纤维蛋白结合小胶质细胞/巨噬细胞上的 CD11b/CD18 整合素受体，诱导促- 对中枢神经系统祖细胞有毒并损害再生的炎症和促氧化途径； 6） fggγ390-396A 敲入小鼠，其中纤维蛋白与 CD11b 整合素的结合位点发生突变，改善了 新生儿全身炎症期间的小脑生长。我们的具体目标将考验我们的工作模式，其中 血脑屏障破坏后纤维蛋白原沉积通过以下方式改变小脑发育：1）直接抑制作用 CGNP 通过 ACVR1 信号传导，2) 通过 CD11b 激活先天免疫反应。在目标 1 中，我们将定义 使用 CGNP 特异性 ACVR1 来研究异常 ACVR1 信号传导对纤维蛋白原诱导的小脑损伤的影响 突变小鼠和临床相关的 ACVR1 小分子抑制剂。在目标 2 中，我们将确定纤维蛋白的作用 使用纤维蛋白原突变小鼠和一种新的方法，CD11b 诱导对小脑损伤的先天免疫激活 阻断纤维蛋白与 CD11b 相互作用的单克隆抗体。在目标 3 中，我们将定义纤维蛋白原如何- ACVR1信号改变诱导多能干细胞衍生小脑中的人小脑祖细胞命运 使用单细胞转录组学的类器官。这些研究将揭示分子机制 神经血管界面将血脑屏障破坏与早产儿脑损伤中的中枢神经系统祖细胞功能障碍联系起来。 因此，该提案的结果可能会开辟新的治疗策略来克服抑制性神经血管 早产儿脑损伤以及其他与血脑屏障破坏和纤维蛋白原相关的神经系统疾病的利基 沉积，如多发性硬化症、阿尔茨海默病和创伤性损伤。