哮喘气道成纤维细胞向肌成纤维细胞的转化受细胞间接触的抑制。
Transition of asthmatic bronchial fibroblasts to myofibroblasts is inhibited by cell-cell contacts.
机构信息
Department of Cell Biology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, Kraków, Poland.
出版信息
Respir Med. 2011 Oct;105(10):1467-75. doi: 10.1016/j.rmed.2011.04.009. Epub 2011 Jul 29.
The role of airway wall remodelling in bronchial asthma is well established. Myofibroblasts, the cells displaying features intermediate between fibroblasts and smooth muscle cells, are involved in this process but the mechanism of myofibroblasts activation in the onset of the disease remains obscure. Myofibroblasts can differentiate from various cell types, including resident fibroblasts, and the fibroblasts to myofibroblasts transition (FMT) can be reproduced in vitro. We aimed to investigate the process of FMT in human bronchial fibroblasts (HBF) derived from non-asthmatic (n = 7) and asthmatic (n = 7) subjects. We also tested whether cell-cell contacts affect FMT by using N-cadherin blocking antibody. HBF plated in low or high cell density were treated with TGF-β(1) up to one week to induce FMT. The percentage of myofibroblsts was counted and expression of α-smooth muscle actin was evaluated by cytoimmunofluorescence, flow cytometry and immunobloting. We demonstrated that the intensity of FMT induced by TGF-β(1)in vitro was strongly enhanced in asthmatic as compared to non-asthmatic HBF populations. This process was facilitated by low cell plating density in both groups of cultures. Furthermore, we proved that neither HBF-conditioned medium nor growth arrest in G(0)/G(1) phase of cell cycle could stop the TGF-β(1)-induced FMT in asthmatic cell populations. However, even in sparse asthmatic HBF, the blocking of N-cadherin resulted in the inhibition of FMT. Our findings show for the first time that the initial absence or an induced loss of cell-cell adhesions in asthmatic HBF populations is important for the completion of FMT.
气道壁重塑在支气管哮喘中的作用已得到充分证实。肌成纤维细胞是一种具有成纤维细胞和平滑肌细胞之间特征的细胞,参与了这一过程,但疾病发生时肌成纤维细胞激活的机制尚不清楚。肌成纤维细胞可以从各种细胞类型分化而来,包括常驻成纤维细胞,并且可以在体外再现成纤维细胞向肌成纤维细胞的转化(FMT)。我们旨在研究源自非哮喘(n=7)和哮喘(n=7)受试者的人支气管成纤维细胞(HBF)中的 FMT 过程。我们还通过使用 N-钙黏蛋白阻断抗体来测试细胞-细胞接触是否影响 FMT。将 HBF 以低或高细胞密度铺板,并用 TGF-β(1)处理长达一周以诱导 FMT。通过细胞免疫荧光、流式细胞术和免疫印迹评估肌成纤维细胞的百分比和α-平滑肌肌动蛋白的表达。我们证明,与非哮喘 HBF 群体相比,TGF-β(1)在体外诱导的 FMT 在哮喘 HBF 群体中强度大大增强。在两组培养物中,低细胞接种密度促进了这一过程。此外,我们证明,无论是 HBF 条件培养基还是细胞周期 G0/G1 期的生长停滞都不能阻止哮喘细胞群体中 TGF-β(1)诱导的 FMT。然而,即使在稀疏的哮喘 HBF 中,阻断 N-钙黏蛋白也会导致 FMT 抑制。我们的研究结果首次表明,哮喘 HBF 群体中初始的细胞-细胞黏附缺失或诱导的丢失对于 FMT 的完成很重要。