Gindele Julia A, Mang Samuel, Pairet Nicolas, Christ Ingrid, Gantner Florian, Schymeinsky Jürgen, Lamb David J
Immunology & Respiratory Diseases Research, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riß, Germany.
Department of Biology, University of Konstanz, Konstanz, Germany.
PLoS One. 2017 Sep 1;12(9):e0184386. doi: 10.1371/journal.pone.0184386. eCollection 2017.
Inappropriate repair responses to pulmonary epithelial injury have been linked to perturbation of epithelial barrier function and airway remodelling in a number of respiratory diseases, including chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis. We developed an in vitro mechanical scratch injury model in air-liquid interface differentiated primary human small airway epithelial cells that recapitulates many of the characteristics observed during epithelial wound injury in both human tissue and small animal models. Wound closure was initially associated with de-differentiation of the differentiated apical cells and rapid migration into the wound site, followed by proliferation of apical cells behind the wound edge, together with increases in FAK expression, fibronectin and reduction in PAI-1 which collectively facilitate cell motility and extracellular matrix deposition. Macrophages are intimately involved in wound repair so we sought to investigate the role of macrophage sub-types on this process in a novel primary human co-culture model. M1 macrophages promoted FAK expression and both M1 and M2 macrophages promoted epithelial de-differentiation. Interestingly, M2a macrophages inhibited both proliferation and fibronectin expression, possibly via the retinoic acid pathway, whereas M2b and M2c macrophages prevented fibronectin deposition, possibly via MMP expression. Collectively these data highlight the complex nature of epithelial wound closure, the differential impact of macrophage sub-types on this process, and the heterogenic and non-delineated function of these macrophages.
在包括慢性阻塞性肺疾病和特发性肺纤维化在内的多种呼吸系统疾病中，对肺上皮损伤的不适当修复反应与上皮屏障功能紊乱和气道重塑有关。我们在气液界面分化的原代人小气道上皮细胞中建立了一种体外机械划痕损伤模型，该模型概括了在人体组织和小动物模型的上皮伤口损伤过程中观察到的许多特征。伤口闭合最初与分化的顶端细胞去分化以及迅速迁移到伤口部位有关，随后伤口边缘后方的顶端细胞增殖，同时粘着斑激酶（FAK）表达增加、纤连蛋白增加以及纤溶酶原激活物抑制剂-1（PAI-1）减少，这些共同促进细胞运动和细胞外基质沉积。巨噬细胞密切参与伤口修复，因此我们试图在一种新型的原代人共培养模型中研究巨噬细胞亚型在此过程中的作用。M1巨噬细胞促进FAK表达，M1和M2巨噬细胞均促进上皮去分化。有趣的是，M2a巨噬细胞可能通过视黄酸途径抑制增殖和纤连蛋白表达，而M2b和M2c巨噬细胞可能通过基质金属蛋白酶（MMP）表达阻止纤连蛋白沉积。这些数据共同凸显了上皮伤口闭合的复杂性、巨噬细胞亚型对这一过程的不同影响，以及这些巨噬细胞的异质性和未明确的功能。
