Ishizaki M, Ishiwata T, Adachi A, Tamura N, Ghazizadeh M, Kitamura H, Sugisaki Y, Yamanaka N, Naito Z, Fukuda Y
Department of Pathology I, Nippon Medical School, Tokyo, Japan.
J Submicrosc Cytol Pathol. 2006 Jun-Sep;38(2-3):193-200.
Nestin is a neuroepithelial precursor cell marker expressed in a variety of human cell types during development. However, no information exists on the expression of nestin in mature glomeruli as well as during the glomerular development. Here, we examined nestin expression in rat and human glomerular tissues in quiescent states using RT-PCR and immunohistochemical methods. Nestin mRNA was detected in the rat glomeruli in parallel with its expression in developing rat brains. In the normal mature rat glomeruli, WT-1 positive cells expressed nestin. Co-expression of nestin and vimentin was observed in mature rat podocytes. Immunoelectron microscopy revealed nestin localization in the cell bodies and primary processes of podocytes. A similar expression pattern was observed for vimentin. In matured glomeruli, nestin was not expressed by mesangial and endothelial cells. In the newborn rat, early developing glomeruli (metanephric cap, metanephric vesicle, comma-shaped vesicle and S-shaped body phases) expressed nestin. In the capillary loop stage, Bowman's capsules also expressed nestin. Immunoelectron microscopy demonstrated that developing podocytes and endothelial cells in S-shaped phase glomeruli expressed nestin. Additionally, in immature glomeruli, the mesangial cells in capillary stage of glomerulus also expressed nexin. As in the rat, WT-1 positive cells in human glomeruli also expressed nestin and immunoelectron microscopy confirmed nestin expression in human glomerular podocytes. These results reveal that in normal condition nestin is expressed in several glomerular cell types at early stage of development and becomes confined to podocytes in mature glomeruli, thus implicating nestin in podocyte functions.
巢蛋白是一种神经上皮前体细胞标志物，在发育过程中在多种人类细胞类型中表达。然而，关于巢蛋白在成熟肾小球以及肾小球发育过程中的表达情况尚无相关信息。在此，我们使用逆转录聚合酶链反应（RT-PCR）和免疫组织化学方法，检测了处于静止状态的大鼠和人类肾小球组织中巢蛋白的表达。在大鼠肾小球中检测到巢蛋白信使核糖核酸（mRNA），其表达与发育中的大鼠大脑中的表达平行。在正常成熟的大鼠肾小球中，WT-1阳性细胞表达巢蛋白。在成熟的大鼠足细胞中观察到巢蛋白和波形蛋白的共表达。免疫电子显微镜显示巢蛋白定位于足细胞的细胞体和初级突起中。波形蛋白也观察到类似的表达模式。在成熟的肾小球中，系膜细胞和内皮细胞不表达巢蛋白。在新生大鼠中，早期发育的肾小球（后肾帽、后肾小泡、逗号形小泡和S形小体阶段）表达巢蛋白。在毛细血管袢阶段，鲍曼囊也表达巢蛋白。免疫电子显微镜表明，S形阶段肾小球中发育中的足细胞和内皮细胞表达巢蛋白。此外，在未成熟的肾小球中，肾小球毛细血管阶段的系膜细胞也表达巢蛋白。与大鼠一样，人类肾小球中的WT-1阳性细胞也表达巢蛋白，免疫电子显微镜证实了人类肾小球足细胞中巢蛋白的表达。这些结果表明，在正常情况下，巢蛋白在发育早期在几种肾小球细胞类型中表达，而在成熟肾小球中局限于足细胞表达，因此提示巢蛋白与足细胞功能有关。
