Université catholique de Louvain (UCL), Institute of Experimental & Clinical Research - Pole of Pneumology, ENT and Dermatology, Avenue Hippocrate 54/B1-54.04, B-1200, Brussels, Belgium.
Department of Pneumology, Cliniques universitaires Saint-Luc, Avenue Hippocrate 10, B-1200, Brussels, Belgium.
Sci Rep. 2019 Nov 29;9(1):17963. doi: 10.1038/s41598-019-54292-x.
In COPD, epithelial changes are prominent features in the airways, such as goblet cell hyperplasia and squamous metaplasia. In contrast, it remains unclear whether ciliated cells are reduced and which pathways dysregulate epithelial differentiation. We hypothesized that bronchial epithelial cell lineage specification is dysregulated in COPD because of an aberrant reprogramming through transforming growth factor (TGF)-β1. Surgical lung tissue from 81 COPD and 61 control (smokers and non-smokers) patients was assessed for bronchial epithelial cell phenotyping by immunohistochemistry, both in situ and in vitro in reconstituted air-liquid interface (ALI) cultures. The role of TGF-β1 was studied in vitro. COPD epithelium in large airways, when compared to controls, showed decreased β-tubulin IV + ciliated cells (4.4%, 2.5-8.8% versus 8.5%, 6.3-11.8% of surface staining, median and IQR, p = 0.0009) and increased MUC5AC + goblet cells (34.8%, 24.4-41.9% versus 10.3%, 5.1-17.6%, p < 0.0001). Both features were recapitulated in the ALI-cultured epithelium from COPD patients. Exogenous TGF-β1 reduced mucociliary differentiation while neutralizing TGF-β1 during ALI increased both specialized cell types. The COPD airway epithelium displays altered differentiation for ciliated cells, which recapitulates in vitro, at least in part through TGF-β1.
在 COPD 中,气道上皮的变化是显著特征,例如杯状细胞增生和鳞状化生。相比之下,纤毛细胞是否减少以及哪些途径导致上皮分化失调仍不清楚。我们假设 COPD 中的支气管上皮细胞谱系特化是失调的,因为转化生长因子 (TGF)-β1 通过异常重编程导致的。通过免疫组织化学,对来自 81 名 COPD 患者和 61 名对照(吸烟者和非吸烟者)患者的手术肺组织进行支气管上皮细胞表型评估,包括原位和在重建的气液界面 (ALI) 培养物中进行。研究了 TGF-β1 的作用。与对照组相比,COPD 大气道上皮中的 β-微管蛋白 IV+纤毛细胞(4.4%,2.5-8.8%比 8.5%,6.3-11.8%的表面染色,中位数和 IQR,p=0.0009)减少,而 MUC5AC+杯状细胞(34.8%,24.4-41.9%比 10.3%,5.1-17.6%,p<0.0001)增加。这两种特征都在 COPD 患者的 ALI 培养上皮中得到了重现。外源性 TGF-β1 减少了黏液纤毛分化,而在 ALI 期间中和 TGF-β1 则增加了两种特化细胞类型。COPD 气道上皮的纤毛细胞分化发生改变,这至少部分通过 TGF-β1 在体外得到了重现。