Phenotype-associated changes in retinal pigment epithelial cell expression of insulin-like growth factor binding proteins.
Phenotype-associated changes in retinal pigment epithelial cell expression of insulin-like growth factor binding proteins.
复制标题
视网膜色素上皮细胞胰岛素样生长因子结合蛋白表达的表型相关变化。
DOI：
10.1167/iovs.09-3383
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发表时间：
2009
影响因子：
4.4
通讯作者：
Guidry,Clyde
中科院分区：
文献类型：
--
作者：
Mukherjee,Sudipto;King,JefferyL;Guidry,Clyde
目的：本研究的目的是评估视网膜色素上皮(RPE)细胞作为胰岛素样生长因子结合蛋白(IGFBPs)的来源，并表征与纤维收缩疾病中已知存在的细胞表型和玻璃体生长因子刺激相关的生物合成变化。方法：通过间接免疫荧光定位和细胞裂解产物的Western印迹分析来表征RPE表型的早期培养相关变化。结果：正常视网膜色素上皮细胞角蛋白18呈免疫阳性反应，细胞角蛋白19、波形蛋白和α-平滑肌肌动蛋白(α-SMA)呈阴性反应。早期反应性RPE(培养7天)表达细胞角蛋白18、细胞角蛋白19和波形蛋白。肌成纤维细胞RPE(培养35天)表达细胞角蛋白19、波形蛋白和αSMA。RT-PCR研究表明，正常RPE可以产生IGFBP-2、-3、-4、-5和-6，但不能产生IGFBP-1。早期反应性和肌纤维母细胞性RPE可检测到IGFBP-3、-5和-6的信息水平。然而，Northern印迹分析表明IGFBP-5是产生的主要结合蛋白。结论：RPE表型的改变伴随着IGFBP表达谱的显著变化，IGFBP-5是肌成纤维细胞产生的主要结合蛋白。
Purpose.: The objectives of this study were to evaluate retinal pigment epithelial (RPE) cells as a source of insulin-like growth factor binding proteins (IGFBPs) and to characterize biosynthetic changes associated with the cell phenotype and vitreous growth factor stimuli known to be present in fibrocontractive diseases.Methods.: Early culture-associated changes in RPE phenotype were characterized by indirect immunofluorescence localization and Western blot analysis of cell lysates. IGFBP expression was evaluated by RT-PCR and Northern blot analysis of total RNA preparations.Results.: Normal unperturbed RPE are immunoreactive for cytokeratin 18 and negative for cytokeratin 19, vimentin, and α-smooth muscle actin (αSMA). Early reactive RPE (7 days in culture) express cytokeratin 18, cytokeratin 19, and vimentin. Myofibroblastic RPE (35 days in culture) express cytokeratin 19, vimentin, and αSMA. RT-PCR studies revealed that normal RPE can produce IGFBP-2,-3,-4,-5, and-6 but not IGFBP-1. Early reactive and myofibroblastic RPE have detectable levels of message for IGFBP-3,-5, and-6. However, Northern blot analysis suggests that IGFBP-5 is the predominant binding protein produced. Finally, stimulation with biologically relevant quantities of IGF-I and IGF-II had no detectable effects on IGFBP expression.Conclusions.: Changes in RPE phenotype are accompanied by dramatic changes in IGFBP expression profile, with IGFBP-5 the predominant binding protein produced by myofibroblastic RPE cells.