Pharmacologic modulation of innate immune dysfunction in heterotopic ossification

异位骨化中先天免疫功能障碍的药物调节

• 批准号: 9767025
• 负责人: EDWARD C HSIAO
• 金额: $ 34.78万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9767025
• 关键词: ACVR1 gene; Acute; Affect; Agonist; Autoimmune Diseases; Biological Assay; Bone Growth; Bone Morphogenetic Proteins; Bypass; Cell physiology; Cells; Chemotaxis; Chondrogenesis; Chronic; Clinical; Coculture Techniques; Data; Disease; Endothelial Cells; Endothelium; Flare; Follow-Up Studies; Fracture; Genetic; Genetic Diseases; Goals; HMGB1 gene; Heterotopic Ossification; Homeostasis; Human; Imatinib; Immune; Immune Cell Activation; Immune System Diseases; Immune system; Immunologics; Inflammation; Inflammatory; Inflammatory Response; Injury; Innate Immune System; Intervention; Intervention Trial; Knowledge; Lead; Lesion; Leukocytes; Ligands; Link; Lipopolysaccharides; Mutation; Natural Immunity; Osteogenesis; Parents; Pathway interactions; Patients; Peripheral; Pharmacologic Substance; Pharmacology; Phase; Physiologic Ossification; Production; Public Health; Randomized; S100A8 gene; S100A9 gene; Severities; Signal Transduction; Sirolimus; Skeletal Development; T-Lymphocyte; TLR1 gene; TLR2 gene; TLR4 gene; Testing; Time; Trauma; activin A; bone; cell type; cohort; cytokine; diagnostic biomarker; effective therapy; efficacy study; improved; induced pluripotent stem cell; inflammatory milieu; innate immune function; macrophage; mast cell; mineralization; monocyte; mouse model; novel; open label; programs; progressive myositis ossificans; receptor; repaired; response; retinoic acid receptor gamma; transcriptome sequencing; treatment strategy

PROJECT SUMMARY/ABSTRACT Heterotopic ossification is a rare but devastating condition of inappropriate bone formation. Although immune system activity is a critical contributor to heterotopic ossification, we lack a clear understanding of how the immune system drives bone formation. Fibrodysplasia ossificans progressiva (FOP) is a genetic disease of massive heterotopic ossification that is associated with inflammatory “flares” that can occur after injury. We recently found that sera from FOP patients have increased levels of pro-inflammatory cytokines at baseline. Furthermore, primary FOP monocytes showed increased responsiveness to LPS, a ligand that stimulates the TLR4 pathway, but not to other ligands that activate other TLR receptors. These preliminary results lead to our central hypothesis that FOP is an autoimmune disease caused by inappropriate activation of the innate immune system. Although there are currently no effective treatments for FOP, retinoic acid receptor-γ (RAR-γ) agonists can inhibit heterotopic ossification in mouse models. UCSF is part of an ongoing multicenter Phase II/III program sponsored by Clementia Pharmaceuticals to study the efficacy of the RAR-γ agonist palovarotene in blocking bone formation in FOP. Preliminary results from a completed randomized study (NCT02190747) and ongoing open label followup study (NCT02279095) indicate that palovarotene can decrease the amount of heterotopic bone formation in FOP subjects. The ongoing open label PVO-1A-202 (NCT02279095) and Phase III PVO-1A-301 (NCT03312634) interventional trials will be the parent studies for the proposed unique and time-sensitive opportunity to elucidate the immune mechanisms in FOP. In Aim 1, we will elucidate how FOP primary monocytes respond to endogenous TLR4 activation. We will assay FOP sera for known endogenous TLR4 activators that can be expressed after trauma, and test if FOP monocytes show increased responsiveness to the TLR4 activators such as HMGB1. In Aim 2, we will test if FOP primary monocytes sensitize endothelial cells to inflammation. We will use co-cultures to assay if FOP monocytes show increased chemotaxis towards FOP endothelial cells and if this is dampened by palovarotene. We will also test if FOP endothelial cells show enhanced pro-inflammatory cytokine expression in the presence of FOP monocytes. These assessments will also show if palovarotene affects immune cell function. In Aim 3, we will determine how ACVR1 and palovarotene change innate immune cell activation. We will use single cell RNAseq to elucidate how the ACVR1 R206H mutation changes the composition of peripheral immune cells, if palovarotene can normalize this profile, and if changes in cytokine production can be linked to inflammation and FOP clinical heterotopic bone formation. Our results will reveal critical inflammatory mechanisms that may provide the first mechanistic and diagnostic biomarkers for disease activity in FOP. The results may also improve our treatment strategies by identifying novel inflammatory targets that may be relevant to other conditions of heterotopic ossification.

项目摘要/摘要 异位骨化是不适当形成的罕见但毁灭性的条件。虽然免疫 系统活动是异位骨化的关键因素，我们对如何如何了解 免疫系统驱动骨形成。纤维状发育异常，Ossificans Progressiva（FOP）是一种遗传疾病 与受伤后可能发生的炎症性“耀斑”相关的大量异位骨化。我们 最近发现，FOP患者的血清在基线时具有促炎性细胞因子的水平升高。 此外，主要的FOP单核细胞显示出对LP的反应性增加，这是一种刺激的配体 TLR4途径，但不是激活其他TLR受体的其他配体。这些初步结果导致我们 中心假设是FOP是由先天性不适当激活引起的自身免疫性疾病 尽管目前尚无有效的FOP治疗方法，但视黄酸受体-γ（RAR-γ） 激动剂可以抑制小鼠模型中的异位骨化。 UCSF是正在进行的多中心II/III的一部分 由Clementia Pharmaceuticals赞助的计划，以研究RAR-γ激动剂的效率 阻塞FOP中的骨形成。完整的随机研究（NCT02190747）和 正在进行的开放标签随访研究（NCT02279095）表明，古罗托烯可以减少 FOP受试者的异位骨形成。正在进行的开放标签PVO-1A-202（NCT02279095）和阶段 III PVO-1A-301（NCT03312634）介入试验将是提议独特的父母研究 和时间敏感的机会，以阐明FOP中的免疫力学。在AIM 1中，我们将阐明 FOP原代单核细胞如何响应内源性TLR4激活。我们将主张已知的FOP血清 可能在创伤后表达的内源性TLR4激活剂，并测试FOP单核细胞是否显示出增加 对TLR4激活剂（例如HMGB1）的响应。在AIM 2中，我们将测试FOP原代单核细胞敏感性是否 内皮细胞炎症。如果FOP单核细胞显示趋化性增加，我们将使用共培养 朝向FOP内皮细胞，如果这是由古罗托烯诅咒的。我们还将测试FOP内皮细胞是否 在FOP单核细胞存在下显示出增强的促炎细胞因子表达。这些评估 还将表明西罗洛尼克烯是否影响免疫细胞功能。在AIM 3中，我们将确定ACVR1和 古罗托烯会改变先天免疫细胞活化。我们将使用单细胞RNASEQ阐明ACVR1的方式 R206H突变会改变周围免疫球的组成，如果古罗托烯可以使该轮廓正常化， 如果细胞因子产生的变化可以与炎症和FOP临床异位骨形成有关。 我们的结果将揭示关键的炎症机制，这些机制可能提供第一个机械和 FOP中疾病活动的诊断生物标志物。结果也可能改善我们的治疗策略 通过识别可能与异位的其他条件相关的新型炎症靶标 骨化。