Department of Internal Medicine, Pulmonary, Critical Care, Sleep and Allergy Medicine, University of Nebraska Medical Center, Omaha, NE 68198-5910, USA.
J Allergy Clin Immunol. 2011 Jun;127(6):1595-603.e9. doi: 10.1016/j.jaci.2011.01.049. Epub 2011 Mar 8.
Fibroblast heterogeneity is recognized, and fibroblasts from diseased tissues, including those of asthmatic subjects, have functional phenotypes that differ from normal tissue. However, progenitor-progeny relationships and the factors that control fibroblast differentiation are poorly defined.
We sought to determine whether IL-4 could alter the functional phenotype of fibroblasts during their differentiation from stem/progenitor cells.
Using a 3-dimensional collagen gel system, we obtained embryoid bodies derived from human embryonic stem cells and recovered spindle-shaped cells consistent with fibroblasts that had differentiated in the presence or absence of IL-4.
IL-4-induced fibroblast-like cells were more active in contraction of collagen gels, migration, and production of fibronectin than control (without IL-4) cells. IL-4-induced cells demonstrated less expression of miR-155, which modulated contraction, migration, and fibronectin production. These differences persisted in culture without further addition of IL-4, suggesting the differentiated phenotype might be a permanent alteration.
The current study demonstrates that IL-4 induces differentiation of stem/precursor cells into fibroblast-like cells that demonstrate a more fibrogenic phenotype, which is due to reduced expression of miR-155. These findings provide a novel mechanism for the persistent abnormalities in IL-4-related diseases and a novel target to regulate tissue remodeling by fibroblasts.
成纤维细胞异质性已被认识到,包括哮喘患者在内的疾病组织中的成纤维细胞具有不同于正常组织的功能表型。然而,祖细胞-后代的关系以及控制成纤维细胞分化的因素还没有被很好地定义。
我们试图确定白细胞介素 4(IL-4)是否可以在干细胞/祖细胞分化为成纤维细胞的过程中改变成纤维细胞的功能表型。
我们使用三维胶原凝胶系统,从人胚胎干细胞中获得胚状体,并回收在有或没有白细胞介素 4(IL-4)存在的情况下分化的纺锤形细胞,这些细胞与成纤维细胞一致。
与对照(无 IL-4)细胞相比,IL-4 诱导的成纤维样细胞在胶原凝胶收缩、迁移和纤连蛋白产生方面更活跃。IL-4 诱导的细胞表现出 miR-155 的表达减少,miR-155 调节收缩、迁移和纤连蛋白的产生。这些差异在没有进一步添加 IL-4 的情况下在培养中持续存在,表明分化表型可能是一种永久性改变。
本研究表明,白细胞介素 4(IL-4)诱导干细胞/前体细胞分化为成纤维样细胞,表现出更具纤维生成表型,这是由于 miR-155 的表达减少。这些发现为 IL-4 相关疾病中持续存在的异常提供了一种新的机制,并为通过成纤维细胞调节组织重塑提供了一个新的靶点。