几种影响小鼠气管上皮基底干细胞体外增殖及分化潜能因素的研究

Characterization of several effectors on proliferation and differentiation potential of airway basal stem cells Gao Jingtao

目的探讨多种细胞组分、细胞因子、信号转导分子等在气管上皮基底干细胞（airway basal stem cells，ABSCs）体外增殖和分化过程中的调控作用。方法采用细胞外基质替代物Matrigel三维体外培养体系，辅以免疫组化分析，观察了几种常见的对干细胞增殖分化发挥重要作用的因素对ABSCs体外集落形成数量、集落大小及分化潜能的影响。结果成纤维细胞较内皮细胞能显著提高ABSCs集落增殖和分化潜能。成纤维细胞生长因子（FGFs）能增加ABSCs体外集落形成数量与直径，并诱导其向分泌性细胞分化。同时给予FGFs及其受体阻滞剂处理，FGFs诱导的集落增殖效应消失。LIF、ALK5-I或ROCK—I处理后，ABSCs形成的集落数量和直径也显著增加，并诱导其向纤毛上皮细胞或分泌性细胞分化。结论小鼠ABSCs不依赖成纤维细胞，但共培养能增强其增殖和分化能力；内皮细胞对ABSCs增殖和分化能力促进作用有限；FGFs促进ABSCs的增殖和分化，其效应能被其受体阻滞剂消除；LIF、ALK5-I或ROCK—I亦促进ABSCs的增殖和分化。研究结果将为小鼠ABSCs的生物学特性及其影响因素的深入研究奠定基础，为未来ABSCs修复性治疗相关疾病和损伤提供了实验学依据。

Objective To clarify the effects of cellular components, cytokines and signal transduction molecules on the proliferation and differentiation potential of airway basal stem cells （ABSCs） in vitro. Methods The extracellular matrix substitute Matrigel three-dimensional culture system in vitro and immunohistochemieal analysis were used to observe the effects of several common factors which played an important role in the proliferation and differentiation of stem cells on the number and size of colonies and differentiation potential of ABSCs. Results Compared with endothelial cells, fibroblasts increased the proliferation and differentiation potential of ABSCs. Fibroblast growth factor （FGFs） increased the number and diameter of ABSCs colonies in vitro, and induced them to differentiate into secretory cells. When the antagonists of FGFs and its receptor were treated, and the colony proliferation effect induced by FGFs disappeared. After treated with LIF, ALKS-I or ROCK-I, the number and diameter of ABSCs colonies also increased significantly and they were induced to differentiate into eiliated epithelial cells or secretory cells. Conclusions Mouse ABSCs does not depend on fibroblasts, but co-culture with fibroblasts can enhance their proliferation and differentiation ability. Endothelial cells limitedly promote the proliferation and differentiation of ABSCs. When treated with FGFs, LIF, ALKS-I or ROCK-I, the proliferation and differentiation of ABSCs are increased. Our results lay a foundation for the further study of ABSCs and shed light on the clinical research and application of airway regenerative medicine in the future.