人类视网膜色素上皮细胞体外培养的转分化

目的:研究人类视网膜色素上皮细胞(human retinal pig-ment epithelium,HRPE)体外培养的转分化现象。方法:倒置显微镜观察体外培养HRPE细胞形态变化;采用免疫细胞化学染色方法检测HRPE细胞角蛋白及α-平滑肌肌动蛋白(α-SMA)的变化。结果:HRPE细胞体外培养时形态由上皮细胞特征变化成为间质样细胞;细胞角蛋白表达与传代代数呈负相关(r=-0.831,P<0.001),α-SMA表达与传代代数呈正相关(r=0.456,P=0.002);角蛋白18表达高密度组较低密度组强(t=2.591,P=0.027);而α-SMA表达高密度组较低密度组弱(t=2.938,P=0.015)。结论:HRPE细胞体外培养转分化主要是体内外环境差异引起。

Research on transdifferentiation of human retinal pigment epithelium cultured in vitro

AIM: To investigate the transdifferentiation of human retinal pigment epithelium (HRPE) cultured in vitro. ·METHODS: The cellular morphology of HRPE was observed by invert microscope and the expressions of keratin and α-smooth muscle actin were detected by immunocytochemistry stain. ·RESULTS: During routine culture on tissue culture plastic, HRPE lost epithelial characteristics and acquired a mesenchymal cell-like phenotype. The cells transdiff-erentiated when continued passage in vitro. This correlated with the loss of the epithelial morphology, decreased expression of the epithelial marker cytokeratin 18, redistribution of the actin cytoskeleton and de novo expression of α-smooth muscle actin. The expression of cytokeratin 18 was negative correlation with continued passage (r=-0.831, P<0.001) and that of α-smooth muscle actin was positive correlation with continued passage(r=0.456,P=0.002). The expression of cytokeratin 18 in high density group was stronger than that in low density group (t=2.591, P=0.027). The expression of α-smooth muscle actin in high density group was weaker than that in low density group (t=2.938, P=0.015). ·CONCLUSION: The morpholigic and behavioral trans-differentiation of HRPE cells cultured in vitro are influenced by the differentia of external environment between in vivo and in vitro.