Pathogenesis of Airway Stem Cell Abnormalities in Obliterative Bronchiolitis

闭塞性细支气管炎气道干细胞异常的发病机制

基本信息

批准号：
9900856
负责人：
Kalpaj Rajnikant Parekh
金额：
$ 58.96万
依托单位：
UNIVERSITY OF IOWA
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2024-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9900856
关键词：
3-Dimensional Abnormal Cell Address Allografting Animal Model Autologous Basal Cell Biological Assay Bronchiolitis Caring Cause of Death Cell Lineage Cell Therapy Cell surface Cells Clinical Data Denervation Development Disease Progression Distal Enterobacteria phage P1 Cre recombinase Epithelial Epithelium Ferrets Fibrosis Foundations Genes Gland Goals Human Immune Targeting Impairment In Vitro Injections Injury Investigation Knock-out Knowledge Lead Left Lobar Lobe Location Lung Lung Transplantation Lung diseases Maintenance Mammals Modeling Morbidity - disease rate Mus Myoepithelial Myoepithelial cell Organoids Outcome Pathogenesis Pathology Pathway interactions Patients Phenotype Play Property Publishing Rattus Regulation Reporter Research Reserve Stem Cell Role Severities Signal Transduction Stem Cell Development Stem cell transplant Structure Surface Testing Therapeutic Time Trachea Transgenes Transgenic Organisms Transplant Recipients Transplantation WNT Signaling Pathway Xenograft procedure airway epithelium cartilaginous editorial effective therapy epithelial stem cell epithelium regeneration exhaustion human model implantation in vivo injury and repair lung allograft lung regeneration mortality novel novel therapeutics overexpression pre-clinical prevent public health relevance regenerative repaired self-renewal stem cell niche stem cell therapy stem cells transcription factor transplant model

项目摘要

Project Summary: End-stage lung diseases are a major cause of morbidity and mortality worldwide. Lung transplantation is an excellent treatment option for patients with this condition, yet 50% of recipients die within five years due to the development of obliterative bronchiolitis (OB) in the allograft. Epithelial stem cell depletion is suggested to contribute to the development of OB; however, there is little research being performed to test this hypothesis, primarily due to the lack of animal models for OB that develop allograft pathology resembling that seen in humans. We recently developed a novel orthotopic lung transplant model in the ferret that models human OB very well. Using this model, we have shown for the first time in ferret and human allografts that the number of clonogenic K5+p63+ basal stem cells (BSCs) progressively declines in proximal and distal airways of the allograft as the severity of OB increases. Additionally, our research is the first to demonstrate that the proximal airway submucosal gland (SMG), a facultative niche for BSCs in the surface airway epithelium (SAE), is an early target of immune destruction in human and ferret allograft airways. In mice, the SMG stem cell niche serves only the trachea; however, in larger mammals such as humans and ferrets, SMGs are present throughout the cartilaginous airways. Using lineage tracing, we have shown that the myoepithelial cells (MECs) of SMGs are precursors of multipotent K5+p63+ BSCs in the SAE. During the development of OB, the destruction of SMG stem cell niches in the allograft occurs simultaneously with phenotypic and functional changes to multipotent K5+p63+ BSCs in the SAE. We hypothesize that destruction of the denervated SMG in the allograft, and thus depletion of MECs, leads to a decline in multipotent K5+p63+ BSCs in the SAE, and to increases in committed multipotent (K5+p63+K14+), bipotent (K5+K14+, p63+K14+) and unipotent (K14+) basal cells, all of which have a reduced capacity for self-renewal. The objective of the proposed research is to determine the functional significance of the phenotypic changes in the MECS and the lineage-committed basal cells and how denervation of the SMG alters Wnt signaling (Lef-1/TCF1) required for both the maintenance of the SMG stem cell niche and lineage commitment of glandular MECs to SAE BSCs in the setting of injury. Additionally, a major preclinical objective of this proposal is to elucidate the ability of stem cells to engraft into a transplanted lung and repair injury, thus laying the foundation for the development of stem cell therapy to delay or prevent OB in lung allografts. We will achieve these objectives by addressing the following specific aims: 1) Determine how destruction of the SMG stem cell niche contributes to depletion of K5+p63+ BSCs. 2) Identify consequences of lung denervation on airway stem cells and their niches. 3) Determine the potential for airway stem cell transplantation in preventing or delaying OB. We expect that delineating the mechanisms of stem cell depletion in the airways of transplanted lungs will be a major step forward in understanding OB pathogenesis and will inform the use of stem cells as a therapeutic approach to prevent or delay OB.

项目概要：终末期肺部疾病是全世界发病和死亡的主要原因。肺移植是一种对于患有这种疾病的患者来说是一个很好的治疗选择，但 50% 的接受者会在五年内死亡。同种异体移植物中发生闭塞性细支气管炎（OB）。建议去除上皮干细胞为OB的发展做出贡献；然而，很少有研究来检验这一假设，主要是由于缺乏 OB 动物模型来形成类似于 OB 的同种异体移植病理学。人类。我们最近在雪貂身上开发了一种新型原位肺移植模型，用于模拟人类 OB 很好。使用这个模型，我们首次在雪貂和人类同种异体移植物中表明，同种异体移植物近端和远端气道中克隆形成的 K5+p63+ 基底干细胞 (BSC) 逐渐减少随着 OB 严重程度的增加。此外，我们的研究首次证明近端气道粘膜下腺 (SMG) 是气道表面上皮 (SAE) 中 BSC 的兼性生态位，是早期靶点人类和雪貂同种异体移植气道中的免疫破坏。在小鼠中，SMG 干细胞生态位仅服务于气管;然而，在人类和雪貂等大型哺乳动物中，SMG 存在于整个身体中。软骨气道。通过谱系追踪，我们发现 SMG 的肌上皮细胞 (MEC) 是 SAE 中多能 K5+p63+ BSC 的前体。 OB开发过程中，SMG被破坏同种异体移植物中的干细胞生态位与多能的表型和功能变化同时发生 SAE 中的 K5+p63+ BSC。我们假设同种异体移植物中去神经的 SMG 被破坏，因此 MEC 的耗尽，导致 SAE 中多能 K5+p63+ BSC 的减少，并导致承诺的增加多能 (K5+p63+K14+)、双能 (K5+K14+、p63+K14+) 和单能 (K14+) 基底细胞，所有这些细胞都具有自我更新能力下降。拟议研究的目的是确定功能 MECS 和谱系定型基底细胞表型变化的重要性以及去神经如何 SMG 的改变改变了维持 SMG 干细胞生态位和维持 SMG 干细胞生态位所需的 Wnt 信号传导 (Lef-1/TCF1) 损伤情况下腺 MEC 对 SAE BSC 的谱系承诺。此外，一项重要的临床前研究该提案的目的是阐明干细胞植入移植肺并修复的能力损伤，从而为干细胞治疗延缓或预防肺OB的发展奠定了基础同种异体移植物。我们将通过解决以下具体目标来实现这些目标： 1) 确定如何 SMG 干细胞生态位的破坏导致 K5+p63+ BSC 的消耗。 2) 确定后果气道干细胞及其生态位的肺去神经支配。 3) 确定气道干细胞的潜力移植可预防或延缓 OB。我们期望描述干细胞耗竭的机制在移植肺的气道中进行检测将是了解 OB 发病机制的重要一步，并将告知使用干细胞作为预防或延迟 OB 的治疗方法。