Targeting pathologic macrophage activation through inhibition of MyD88 to attenuate laryngotracheal stenosis

通过抑制 MyD88 靶向病理性巨噬细胞激活以减轻喉气管狭窄

• 批准号: 10644555
• 负责人: Kevin Motz
• 金额: $ 19.76万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-03-01 至 2028-02-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10644555
• 关键词: Adult; Attenuated; Automobile Driving; Biological Response Modifiers; Biopsy; Bypass; CD4 Positive T Lymphocytes; Cells; Collagen; Communication impairment; Critical Illness; Critical Pathways; Data; Development; Disease; Dysphonia; Dyspnea; Excision; Experimental Designs; Fibrosis; Flow Cytometry; Foundations; Gene Expression; Goals; Histologic; Human; Iatrogenesis; Immune; Immune Targeting; Immune response; Immunology; Immunophenotyping; Inflammation; Inflammatory Infiltrate; Injury; Interleukin-1 beta; Intervention; Intratracheal Intubation; Intubation; Investigation; Knowledge; Laboratories; Lamina Propria; Laryngeal Diseases; Larynx; Lead; Life; Macrophage; Macrophage Activation; Mediating; Medical; Mentors; Modeling; Molecular; Mucous Membrane; Mus; Operative Surgical Procedures; Pathogenesis; Pathologic; Pathway interactions; Patients; Pattern; Phenotype; Physiological; Population; Proteins; Regulatory Pathway; Research; Research Training; Resected; Role; S100A8 gene; Secondary to; Serum; Signal Pathway; Signal Transduction; Source; Stenosis; Subglottis structure; TLR4 gene; Therapeutic Intervention; Tissues; Toll-like receptors; Trachea; Tracheostomy procedure; Transgenic Organisms; biomarker development; candidate marker; career; cytokine; experience; genetic regulatory protein; improved; mouse model; pathogen; prevent; protein expression; receptor; single-cell RNA sequencing; skills; targeted treatment; treatment strategy; wound healing

Project Summary: Laryngotracheal Stenosis (LTS) is the pathologic narrowing of the larynx, subglottis, and trachea secondary to mucosal injury from prolonged intubation. This narrowing leads to dyspnea, dysphonia, and can rapidly progress to airway compromise. Therapeutic interventions for the management of LTS are limited to serial dilation, tracheal resection, or permanent tracheostomy which further impairs communication. Medical therapies for LTS are limited by our poor understanding of LTS pathogenesis. Improved understanding of the mechanisms promoting LTS is needed to improve treatment of this debilitating disease. Previous investigation has revealed that an intact immune response is critical to the development of LTS. Characterization of the immune response in LTS has demonstrated increased populations of CD4+ T-cells and macrophages. Preliminary studies in a murine LTS model reveal that depletion of the macrophage population attenuates LTS fibrosis, implicating their pathologic role. However, the local immune mediators and cell signaling pathways promoting pathologic macrophages in LTS are unknown. Macrophage activation is regulated through stimulation of Toll-like receptors (TLRs). TLRs are highly conserved receptors recognizing Pathogen or Damage Associated Molecular Patterns (PAMPs/DAMPs) and lead to downstream activation of regulatory proteins controlling phenotype. Using single cell RNA sequencing the PI has demonstrates increased expression of the TLR4-MyD88 signaling pathway in LTS macrophages. Furthermore, we have identified increased expression of the DAMP S100A8/A9 in LTS tissue. S100A8/A9 is a known activator of TLR4-MyD88 signaling, and worsens fibrosis in our murine LTS model. These findings indicate that TLR4-MyD88 signaling pathways in macrophages may be critical to LTS pathogenesis. However, the relationship between S100A8/A9, TLR4-MyD88 signaling, and pathologic macrophages has not been explored in LTS or other fibrotic diseases, and may represent a critical signaling axis driving pathologic fibrosis. For this study, we will elucidate the signaling networks promoting pathologic macrophages in laryngotracheal stenosis. In Aim 1 we will assess effect of S100A8/A9 on macrophage phenotype and function in a murine LTS model, establish that S100A8/A9s profibrotic effect is mediated by macrophages, and identify the key sources of pathologic S100A8/A9 in human LTS and a murine model. In Aim 2, we will demonstrate the critical role of TLR4-MyD88 signaling in promoting pathologic macrophages in LTS, and elucidate the role of IL1β in promoting LTS fibrosis. Finally, in Aim 3 we will assess S100A8/A9 as a candidate biomarker for the development of laryngotracheal stenosis in patients who have had prolonged intubation. Collectively, this application will lead to an in-depth understanding of the cell signaling networks promoting dysregulated macrophage mediated inflammation and subsequent fibrosis in LTS. The identification of key regulatory pathways promoting pathologic macrophages in LTS will serve as the foundation for targeted treatment strategies that attenuate fibrosis.

项目概要： 喉气管狭窄 (LTS) 是喉部、声门下和气管的病理性狭窄 继发于长时间插管造成的粘膜损伤。这种狭窄会导致呼吸困难、发声困难，并且可以 迅速进展至气道受损。 LTS 管理的治疗干预措施仅限于 连续扩张、气管切除或永久性气管切开术进一步损害沟通。医疗的 由于我们对 LTS 发病机制了解甚少，LTS 的治疗受到限制。增进了对 需要促进 LTS 的机制来改善这种使人衰弱的疾病的治疗。 先前的研究表明，完整的免疫反应对于 LTS 的发展至关重要。 LTS 中免疫反应的特征表明 CD4+ T 细胞数量增加，并且 巨噬细胞。小鼠 LTS 模型的初步研究表明，巨噬细胞群的消耗 减轻 LTS 纤维化，暗示其病理作用。然而，局部免疫介质和细胞信号传导 LTS 中促进病理性巨噬细胞的途径尚不清楚。 巨噬细胞的激活是通过刺激 Toll 样受体 (TLR) 来调节的。 TLR 高度 识别病原体或损伤相关分子模式 (PAMP/DAMP) 的保守受体 导致控制表型的调节蛋白的下游激活。使用单细胞 RNA 测序 PI 证明 LTS 巨噬细胞中 TLR4-MyD88 信号通路的表达增加。 此外，我们还发现 LTS 组织中 DAMP S100A8/A9 的表达增加。 S100A8/A9 是 已知的 TLR4-MyD88 信号传导激活剂，并会恶化我们的小鼠 LTS 模型中的纤维化。这些发现 表明巨噬细胞中的 TLR4-MyD88 信号通路可能对 LTS 发病机制至关重要。然而， S100A8/A9、TLR4-MyD88 信号传导和病理性巨噬细胞之间的关系尚未明确 在 LTS 或其他纤维化疾病中进行了探索，可能代表驱动病理性纤维化的关键信号轴。 在本研究中，我们将阐明促进喉气管病理性巨噬细胞的信号网络 狭窄。在目标 1 中，我们将评估 S100A8/A9 对小鼠 LTS 中巨噬细胞表型和功能的影响 模型，建立 S100A8/A9s 促纤维化作用是由巨噬细胞介导的，并确定关键来源 人类 LTS 和小鼠模型中的病理性 S100A8/A9。在目标 2 中，我们将展示以下关键作用： TLR4-MyD88 信号传导促进 LTS 中的病理性巨噬细胞，并阐明 IL1β 在促进 LTS 纤维化。最后，在目标 3 中，我们将评估 S100A8/A9 作为开发 长期插管的患者出现喉气管狭窄。总的来说，该应用程序将导致 深入了解促进巨噬细胞介导失调的细胞信号网络 LTS 中的炎症和随后的纤维化。促进病理的关键调控途径的确定 LTS 中的巨噬细胞将成为减轻纤维化的靶向治疗策略的基础。