Popov Boris V, Serikov Vladimir B, Petrov Nikolay S, Izusova Tatiana V, Gupta Naveen, Matthay Michael A
Children's Hospital Oakland Research Institute, Oakland, CA, USA.
Tissue Eng. 2007 Oct;13(10):2441-50. doi: 10.1089/ten.2007.0001.
Mesenchymal stem cells (MSCs) from bone marrow are a potential source for reconstructive therapy. In vitro, MSCs differentiate into cells of mesodermal and ectodermal lineages but rarely into cells of endodermal lineage. We developed an in vitro model to study the endodermal differentiation of MSCs using co-culture of MSCs and transformed lung epithelial (A-549) cells. The cells were separated using a cell-impermeable membrane to eliminate the possibility of cell fusion. Under these conditions, MSCs expressed several lung epithelial markers (cytokeratins 5, 8, 14, 18, 19, pro-surfactant protein C, zonula occludens-1), detected using quantitative reverse transcriptase polymerase chain reaction and Western blot, and beta-catenin signaling was activated in MSCs. Treatment of MSCs with 10 to 20 mM lithium chloride activated the beta-catenin pathway and enhanced expression of epithelial markers, although this activation was transient. We conclude that A-549 cells can trigger epithelial differentiation of MSCs by a paracrine mechanism that may include activation of beta-catenin signaling.
来自骨髓的间充质干细胞（MSCs）是重建治疗的潜在细胞来源。在体外，MSCs可分化为中胚层和外胚层谱系的细胞，但很少分化为内胚层谱系的细胞。我们开发了一种体外模型，通过MSCs与转化的肺上皮（A-549）细胞共培养来研究MSCs的内胚层分化。使用细胞不可渗透膜分离细胞以消除细胞融合的可能性。在这些条件下，MSCs表达了几种肺上皮标志物（细胞角蛋白5、8、14、18、19、前表面活性蛋白C、紧密连接蛋白-1），通过定量逆转录聚合酶链反应和蛋白质免疫印迹检测到，并且β-连环蛋白信号在MSCs中被激活。用10至20 mM氯化锂处理MSCs可激活β-连环蛋白途径并增强上皮标志物的表达，尽管这种激活是短暂的。我们得出结论，A-549细胞可通过一种旁分泌机制触发MSCs的上皮分化，该机制可能包括β-连环蛋白信号的激活。
