Dissecting mechanisms of alveolar repair failure and lung destruction in lymphangioleiomyomatosis

淋巴管平滑肌瘤病肺泡修复失败和肺破坏的解剖机制

• 批准号: MR/T002042/1
• 负责人: Simon Johnson
• 金额: $ 54.07万
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FT002042%2F1
• 关键词: Dissecting; mechanisms; alveolar; repair; failure

Lymphangioleiomyomatosis (LAM) is a rare, progressive and incurable disease causing respiratory failure, lymphatic abnormalities and renal tumours which almost exclusively affects women. LAM arises due to loss of function of genes which control mTOR, a key cellular regulator in a specific cell type called the LAM cell. Constant mTOR activation allows LAM cells to multiply, survive in adverse conditions and invade the lungs and lymphatic tissue to cause tissue damage. In LAM, the lungs are continually damaged leading to progressive breathlessness and lung collapse, but the mechanisms causing this lung damage are not understood. The lungs are continually exposed to harmful chemicals and particles in the environment and are normally able to repair low level damage as it occurs. However due to aging or disease, these repair mechanisms become less efficient resulting in impaired lung function. In this work we will test the idea that senescence, a biological process that normally reduces the capacity of abnormal cells which develop during aging, occurs prematurely in LAM as a result of mTOR activation. We think that senescent LAM cells produce factors that induce senescence in surrounding cells, including alveolar type II cells which are normally responsible for replacing damaged alveolar epithelial cells. This mTOR induced senescence therefore reduces alveolar repair contributing to lung damage in LAM. We have already shown that cells within both LAM lung nodules and the surrounding alveoli express multiple genes and protein markers associated with senescence. In our animal model of LAM, senescence markers increase over time and are associated with progressive lung damage. In this work we will systematically examine how mTOR activation leads to senescence in LAM. To do this we will examine alveolar epithelial cell gene expression in LAM and control lungs using single cell RNA sequencing which allows measurement of gene expression in individual cell populations from LAM lungs taken at lung transplants. To study early LAM we will also measure gene expression in alveolar cells and LAM nodules by laser capture microdissection in diagnostic biopsy tissue to isolate specific cell populations. By using gene expression analysis tools we will examine which signaling pathways are active in epithelial cells in LAM and how these relate to cell death and repair. Next, using upstream regulator analysis, a tool which predicts which mediators result in specific gene changes we will examine which soluble proteins from LAM nodules affect epithelial cell repair and how this is related to mTOR activation. Using 40 individual lung biopsies with linked clinical data we will confirm these gene changes in human tissue and importantly, how these proteins are related to duration of disease and disease progression measured by prospective loss of lung function. Once we have understood which LAM cell derived factors result in reduced alveolar repair we will use novel 3D tissue culture systems we have developed to study how these processes are regulated and how they affect alveolar cell repair in vitro by using drugs or gene editing to block individual proteins. We will then examine these processes in a mouse model of LAM we have developed in our lab. The model will allow us to examine these changes in a whole organism and assess how blocking key proteins and processes, including mTOR activation and senescence affects lung damage. These experiments will shed new light on LAM and other lung diseases where mTOR activation contributes to lung damage. Using these data to understand how lung damage occurs we hope to improve treatments for LAM and potentially other destructive lung diseases.

淋巴血管肌瘤病（LAM）是一种罕见，进行性和无法治愈的疾病，导致呼吸衰竭，淋巴异常和肾肿瘤几乎完全影响女性。 LAM是由于控制MTOR的功能的丧失，后者是MTOR，这是一种称为LAM细胞的特定细胞类型中的钥匙细胞调节剂。恒定的MTOR激活使LAM细胞在不良条件下生存，并侵入肺和淋巴组织，从而导致组织损伤。在林中，肺部不断受损，导致呼吸困难和肺部塌陷，但尚不清楚导致这种肺部损伤的机制。肺部不断暴露于环境中的有害化学物质和颗粒，通常能够在发生时修复低水平的损害。但是，由于衰老或疾病，这些修复机制变得效率降低，导致肺功能受损。在这项工作中，我们将测试衰老，即通常会降低衰老过程中异常细胞能力的生物学过程，这是由于mTOR激活而过早发生的。我们认为，衰老的LAM细胞会产生可诱导周围细胞衰老的因素，包括通常负责替代受损肺泡上皮细胞的肺泡II型细胞。因此，这种MTOR诱导的衰老减少了肺泡修复，导致LAM肺损伤。我们已经表明，在Lam肺结节中和周围的肺泡中的细胞表达多个基因和与衰老相关的蛋白质标记。在我们的LAM动物模型中，衰老标记随着时间的推移增加，并且与进行性肺损伤有关。在这项工作中，我们将系统地研究MTOR激活如何导致LAM衰老。为此，我们将使用单细胞RNA测序来检查LAM中肺泡上皮细胞基因的表达，并控制肺部的肺部RNA测序，该测序允许在肺移植物处于肺部肺肺中测量单个细胞群中的基因表达。为了研究早期的LAM，我们还将通过激光捕获诊断活检组织中的显微解剖来测量肺泡细胞和LAM结节中的基因表达，以分离特定的细胞群体。通过使用基因表达分析工具，我们将检查哪些信号通路在LAM的上皮细胞中有效，以及它们与细胞死亡和修复的关系。接下来，使用上游调节剂分析，一种预测哪些介体导致特定基因变化的工具，我们将检查哪些LAM结节的可溶性蛋白会影响上皮细胞修复以及这与MTOR激活如何相关。使用40个单独的肺活检和连接的临床数据，我们将确认人类组织中的这些基因变化，重要的是，这些蛋白质与疾病的持续时间和疾病进展如何通过肺功能的前瞻性丧失来衡量。一旦我们了解了哪些LAM细胞衍生的因子导致牙槽修复减少，我们将使用新型的3D组织培养系统，我们开发了如何通过使用药物或基因编辑来阻断各个蛋白质来研究这些过程如何调节这些过程，以及它们如何在体外影响肺泡细胞修复。然后，我们将在实验室中开发的LAM的小鼠模型中检查这些过程。该模型将使我们能够检查整个生物体中的这些变化，并评估关键蛋白质和过程（包括MTOR激活和衰老）如何影响肺损伤。这些实验将为LAM和其他肺部疾病提供新的启示，其中MTOR激活有助于肺部损伤。使用这些数据来了解肺部损伤是如何发生的，我们希望改善对LAM和其他破坏性肺部疾病的治疗方法。

项目成果

Histamine signaling and metabolism identify potential biomarkers and therapies for lymphangioleiomyomatosis.

• DOI: 10.15252/emmm.202113929
• 发表时间: 2021-09-07
• 期刊: EMBO molecular medicine
• 影响因子: 11.1
• 作者: Herranz C;Mateo F;Baiges A;Ruiz de Garibay G;Junza A;Johnson SR;Miller S;García N;Capellades J;Gómez A;Vidal A;Palomero L;Espín R;Extremera AI;Blommaert E;Revilla-López E;Saez B;Gómez-Ollés S;Ancochea J;Valenzuela C;Alonso T;Ussetti P;Laporta R;Xaubet A;Rodríguez-Portal JA;Montes-Worboys A;Machahua C;Bordas J;Menendez JA;Cruzado JM;Guiteras R;Bontoux C;La Motta C;Noguera-Castells A;Mancino M;Lastra E;Rigo-Bonnin R;Perales JC;Viñals F;Lahiguera A;Zhang X;Cuadras D;van Moorsel CHM;van der Vis JJ;Quanjel MJR;Filippakis H;Hakem R;Gorrini C;Ferrer M;Ugun-Klusek A;Billett E;Radzikowska E;Casanova Á;Molina-Molina M;Roman A;Yanes O;Pujana MA
• 通讯作者: Pujana MA

Pulmonary Lymphangioleiomyomatosis originates in the pleural mesothelial cell population.

肺淋巴管平滑肌瘤病起源于胸膜间皮细胞群。

• DOI: 10.1016/j.mehy.2020.109703
• 发表时间: 2020
• 期刊: Medical hypotheses
• 影响因子: 4.7
• 作者: Clements D