Jun E S, Kim Y S, Roh H J, Jung J S
Department of Molecular Biology, College of Natural Science, Pusan National University, Korea.
Life Sci. 2001 Jan 5;68(7):827-40. doi: 10.1016/s0024-3205(00)00985-1.
Integrity of the airway epithelium is important for pulmonary defense mechanisms to infection. The lining of the airway contains a diverse population of cell types. Understanding about progenitor-progeny relationships during renewal of airway epithelium is important for elucidating mechanisms of injury repair or oncogenesis. Primary culture of airway epithelia is a good model for studying differentiation process of epithelial cells. Ion channels and aquaporins(AQPs) play a critical role on ion and fluid transport across airway epithelia. However, changes in their expression during differentiation of airway epithelial cells have not been reported yet. This study was undertaken to identify isoforms of aquaporins in cultured normal human nasal epithelial cells (NHNE) and effects of various culture conditions on expression of differentiation markers and channels. 1. Degenerative RT-PCR revealed that AQP3 and AQP4 are expressed in cultured NHNE cells. 2. Culture of NHNE cells on permeable filters induced expression of mucin, aquaporins and CFTR. 3. Retinoic acid induced morphological changes in NHNE cells and inhibited their proliferation. The treatment of retinoic acid induced expression of mucin and CFTR, whereas it inhibited expression of cornifin. The effect of retinoic acid was enhanced by culture of cells on permeable filters. 4. Dexamethasone induced ENaC expression in NHNE cells grown on permeable supports only, but did not affect expression of mucin, aquaporins and CFTR. These results indicate that cultured NHNE cells express aquaporins (AQP3 and 4), CFTR and ENaC, and culture of NHNE cells on permeable filters induces differentiation in to mucosecretory and surface epithelial cells, and that effects of retinoic acid and dexamethasone on gene expression are affected by culture conditions.
气道上皮的完整性对于肺部抗感染防御机制至关重要。气道内衬包含多种细胞类型。了解气道上皮更新过程中的祖细胞 - 子代关系对于阐明损伤修复或肿瘤发生机制很重要。气道上皮的原代培养是研究上皮细胞分化过程的良好模型。离子通道和水通道蛋白（AQP）在跨气道上皮的离子和液体运输中起关键作用。然而，尚未报道它们在气道上皮细胞分化过程中的表达变化。本研究旨在鉴定培养的正常人鼻上皮细胞（NHNE）中水通道蛋白的异构体以及各种培养条件对分化标志物和通道表达的影响。1. 逆转录 - 聚合酶链反应（RT - PCR）显示AQP3和AQP4在培养的NHNE细胞中表达。2. 在可渗透滤器上培养NHNE细胞可诱导粘蛋白、水通道蛋白和囊性纤维化跨膜传导调节因子（CFTR）的表达。3. 视黄酸诱导NHNE细胞形态变化并抑制其增殖。视黄酸处理诱导粘蛋白和CFTR的表达，而抑制角蛋白的表达。在可渗透滤器上培养细胞可增强视黄酸的作用。4. 地塞米松仅在可渗透支持物上生长的NHNE细胞中诱导上皮钠通道（ENaC）表达，但不影响粘蛋白、水通道蛋白和CFTR的表达。这些结果表明，培养的NHNE细胞表达水通道蛋白（AQP3和4）、CFTR和ENaC，在可渗透滤器上培养NHNE细胞可诱导其分化为粘液分泌细胞和表面上皮细胞，并且视黄酸和地塞米松对基因表达的影响受培养条件影响。
