Portelli Michael A, Bhaker Sangita, Pang Vincent, Bates David O, Johnson Simon R, Mazar Andrew P, Shaw Dominick, Brightling Christopher, Sayers Ian
Centre for Respiratory Research, NIHR Respiratory Biomedical Research Centre, School of Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, UK.
Tumour Vascular Biology Group, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, UK.
Clin Transl Allergy. 2023 Oct;13(10):e12293. doi: 10.1002/clt2.12293.
Expression of the urokinase plasminogen activator receptor (uPAR) is elevated in the airway epithelium in asthma; however, the contribution of uPAR to asthma pathogenesis and scope for therapeutic targeting remains unknown.
To determine (i) the expression profile of uPAR in cultured human bronchial epithelial cells (HBEC) from asthma patients, (ii) the relationship between uPAR and the epithelial barrier, including blocking uPAR functions and (iii) the function of different uPAR isoforms.
uPAR levels in HBECs isolated from asthma patients and cells at air liquid interface (ALI) during differentiation were quantified. Transepithelial electrical resistance or electrical cell impedance sensing was used to relate uPAR levels to barrier properties, including effects of uPAR blocking antibodies. The functional effects of gain of function was determined using transcriptomics, in cells over-expressing membrane (muPAR), soluble cleaved (scuPAR) or soluble spliced (ssuPAR) isoforms.
Elevated expression of uPAR was a feature of cultured HBECs from asthma patients, suggesting intrinsic alterations in asthma patient cells. Soluble uPAR levels inversely correlated with barrier properties of the HBEC layer in 2D and ALI. Blocking uPAR-integrin interactions enhanced barrier formation. The gain of function cells showed limited transcriptomic changes.
This study provides a significant advance in our understanding of the relationship between asthma, uPAR and the epithelial barrier, where elevated circulating uPAR results in a reduced cell barrier, a phenotype prevalent in asthma.
哮喘患者气道上皮中尿激酶型纤溶酶原激活物受体（uPAR）的表达升高；然而，uPAR对哮喘发病机制的作用以及治疗靶点的范围仍不清楚。
确定（i）哮喘患者培养的人支气管上皮细胞（HBEC）中uPAR的表达谱，（ii）uPAR与上皮屏障之间的关系，包括阻断uPAR功能，以及（iii）不同uPAR异构体的功能。
对从哮喘患者分离的HBECs以及分化过程中处于气液界面（ALI）的细胞中的uPAR水平进行定量。使用跨上皮电阻或细胞电阻抗传感来将uPAR水平与屏障特性相关联，包括uPAR阻断抗体的作用。在过表达膜（muPAR）、可溶性裂解（scuPAR）或可溶性剪接（ssuPAR）异构体的细胞中，使用转录组学确定功能获得的功能效应。
uPAR表达升高是哮喘患者培养的HBECs的一个特征，提示哮喘患者细胞存在内在改变。可溶性uPAR水平与二维和ALI中HBEC层的屏障特性呈负相关。阻断uPAR-整合素相互作用可增强屏障形成。功能获得细胞显示出有限的转录组变化。
本研究在我们对哮喘、uPAR和上皮屏障之间关系的理解方面取得了重大进展, 其中循环uPAR升高导致细胞屏障降低，这是哮喘中普遍存在的一种表型。
