Institut Für Molekularbiologie, OE5250, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
Histochem Cell Biol. 2022 Oct;158(4):389-399. doi: 10.1007/s00418-022-02120-1. Epub 2022 Jun 1.
The urothelium is a stratified epithelium that lines the inner surface of the components of the urinary drainage system. It is composed of a layer of basal cells, one or several layers of intermediate cells, and a layer of large luminal superficial or umbrella cells. In the mouse, only a small set of markers is available that allows easy molecular distinction of these urothelial cell types. Here, we analyzed expression of S100A1, a member of the S100 family of calcium-binding proteins, in the urothelium of the two major organs of the murine urinary tract, the ureter and the bladder. Using RNA in situ hybridization analysis, we found exclusive expression of S100a1 mRNA in luminal cells of the ureter from embryonic day (E)17.5 onwards and of the bladder from E15.5 to adulthood. Immunofluorescence analysis showed that expression of S100A1 protein is confined to terminally differentiated superficial cells of both the ureter and bladder where it localized to the nucleus and cytoplasm. We conclude that S100A1 is a suitable marker for mature superficial cells in the urothelial lining of the drainage system of the developing and mature mouse.
尿路上皮是一种复层上皮，排列在泌尿系统各组成部分的内表面。它由一层基底细胞、一层或多层中间细胞和一层大的腔面浅层或伞状细胞组成。在小鼠中，只有一小部分标记物可用于容易地区分这些尿路上皮细胞类型。在这里，我们分析了 S100A1 在小鼠泌尿道的两个主要器官——输尿管和膀胱中的尿路上皮中的表达。使用 RNA 原位杂交分析，我们发现 S100a1 mRNA 从胚胎第 17.5 天（E）开始在输尿管的腔面细胞中特异性表达，从 E15.5 到成年期在膀胱中表达。免疫荧光分析显示 S100A1 蛋白的表达仅限于输尿管和膀胱的终末分化浅层细胞，其定位在细胞核和细胞质中。我们得出结论，S100A1 是发育中和成熟的小鼠泌尿道尿路上皮衬里中成熟浅层细胞的合适标记物。
