体外培养人羊膜上皮细胞的表型及分化能力

Phenotype and differentiation capacity of human amniotic epithelial cells cultured in vitro

背景:人羊膜上皮细胞具有多系分化能力,是再生医学中重要的细胞来源。目前的研究多集中于对其分化能力的考察,而体外培养过程中羊膜上皮细胞的生物学特征如何变化尚不清楚。目的:分析体外培养对人羊膜上皮细胞生长、表型及向心肌样细胞分化的能力等生物学特性的影响,探讨原代人羊膜上皮细胞干性标志物SSEA-4的表达水平与人羊膜上皮细胞生物学特性变化之间的关联性。方法:使用统一分离方法获得原代羊膜上皮细胞并进行体外培养。利用CCK-8、流式细胞仪及real-time PCR等手段检测不同培养阶段人羊膜上皮细胞的增殖、表型以及向心肌样细胞分化的能力。结果与结论:不同胎儿样本来源的原代人羊膜上皮细胞的SSEA-4表达在26.7%-97%,存在很大的个体差异。并且,随着传代次数的增加,人羊膜上皮细胞的SSEA-4表达水平显著降低,其下降程度与原代SSEA-4的表达水平无关。另外,培养后人羊膜上皮细胞的心肌分化潜能也存在很大个体差异,且其差异与原代人羊膜上皮细胞的SSEA-4表达水平的高低无关。结果提示,不同胎儿样本来源的原代人羊膜上皮细胞的SSEA-4表达水平受到个体差异的影响,需要建立更准确的临床样本筛选指标来稳定获得原代高表达SSEA-4的胎儿样本,以实现对人羊膜上皮细胞的质量监控。另外,体外培养过程中SSEA-4的表达水平受到培养条件的影响,需要继续优化培养条件以维持其高表达。此外,人羊膜上皮细胞向心肌样细胞分化的能力受到样本个体差异以及培养条件的影响,在今后还需要进一步研究。

BACKGROUND： Human amniotic epithelial cells are an important source of cells in regenerative medicine as its multipotentation, but new studies mainly focused on differentiation features and there were little research oneffect of culture in vitro on biological property of amniotic epithelial cells. OBJECTIVE： To analyze the effects of in vitro culture on growth, cell phenotype and differentiation capacity of human amniotic epithelial cells into cardiomyocyte-like cells, and explore the correlation of primarily cultured human amniotic epithelial cells marker SSEA-4 expression level and the change of biological characteristics of human amniotic epithelial cells. METHODS： Primarily cultured human amniotic epithelial cells were obtained from amniotic tissues by using the same separation protocol. Human amniotic epithelial cells were cultured in vitro. The proliferation, cell phenotype and the differentiation capacity of human amniotic epithelial cells into cardiomyocyte-like cells were evaluated by means of cell counting kit-8, flow cytometry and real-time PCR. RESULTS AND CONCLUSION： The SSEA-4 positive cells in primarily cultured human amniotic epithelial cells from different fetal tissues were between 26.7%-97%, which indicated that there was great individual difference among amniotic tissue samples. Moreover, with passage, the SSEA-4 expression in human amniotic epithelial cells decreased significantly, which did not correlate with the SSEA-4 expression in primarily cultured human amniotic epithelial cells. Results indicated that there was great individual difference in SSEA-4 expression level in primarily cultured human amniotic epithelial cells from different amniotic tissue samples. Thus, it is necessary to set up clinical screening indexes to get samples with higher SSEA-4 expression stably and to control the quality of human amniotic epithelial cells. In addition, during culture period, SSEA-4 expression level was affected by culture conditions. The culture conditions of human amniotic epithelial cells should be optimized to maintain SSEA-4 expression at a high level. In addition, the differentiation capacity of human amniotic epithelial cells into cardiomyocyte-like cells was also affected by individual difference among different samples and culture conditions, which will be further studied in the future.