Yaoita E, Franke W W, Yamamoto T, Kawasaki K, Kihara I
Department of Pathology, Institute of Nephrology, Niigata University School of Medicine, Japan.
Histochem Cell Biol. 1999 Feb;111(2):107-15. doi: 10.1007/s004180050340.
We sought to characterize podocytes in the kidneys of numerous species from amphibians to mammals because of the pivotal function of these cells in renal diseases. For this purpose, intermediate filament (IF) proteins of podocytes were examined by immunofluorescence microscopy using antibodies against vimentin, cytokeratins, and desmin. These staining patterns were then compared to those of parietal cells of Bowman's capsule and tubular cells of the first portion of the proximal tubule from the same sources. As a result, podocytes from mammals (rat, rabbit, dog, cow, and human) and birds (chicken) showed intense vimentin staining without exception, but rarely staining for cytokeratins or desmin. Parietal cells from all these animals were highly heterogeneous with respect to cytokeratin or vimentin staining. Of the tubular cells, only those from humans and chickens were reactive and then only with anti-cytokeratin antibodies. In the reptiles (Chrysemys scripta elegans, Chinemys reeveri, Elaphe quadrivirgata, and Anolis carolinensis), podocytes and other epithelial cells were positive for cytokeratins. Vimentin staining differed among the species, but was not characteristic for podocytes. Anti-desmin antibody reacted strongly only with podocytes from Anolis. In amphibians (Rana catesbeiana and Xenopus laevis), anti-desmin antibody stained podocytes more intensely than any other cell. Cytokeratin and vimentin staining did not differentiate podocytes from the other cell types. These findings indicate that podocytes are characterized by intense vimentin staining in the higher vertebrates and by desmin staining in the lower vertebrates denoting potentially distinctive physiological functions of IF proteins in podocytes from each of these groups.
由于足细胞在肾脏疾病中具有关键作用，我们试图对从两栖动物到哺乳动物等众多物种的肾脏中的足细胞进行表征。为此，使用针对波形蛋白、细胞角蛋白和结蛋白的抗体，通过免疫荧光显微镜检查足细胞的中间丝（IF）蛋白。然后将这些染色模式与来自相同来源的鲍曼囊壁层细胞和近端小管起始段的肾小管细胞的染色模式进行比较。结果，来自哺乳动物（大鼠、兔子、狗、牛和人类）和鸟类（鸡）的足细胞无一例外都显示出强烈的波形蛋白染色，但很少有细胞角蛋白或结蛋白染色。所有这些动物的壁层细胞在细胞角蛋白或波形蛋白染色方面高度异质。在肾小管细胞中，只有来自人类和鸡的细胞有反应，并且仅与抗细胞角蛋白抗体有反应。在爬行动物（秀丽锦龟、中华草龟、四线锦蛇和绿安乐蜥）中，足细胞和其他上皮细胞对细胞角蛋白呈阳性。波形蛋白染色在不同物种间存在差异，但并非足细胞所特有。抗结蛋白抗体仅与绿安乐蜥的足细胞强烈反应。在两栖动物（牛蛙和非洲爪蟾）中，抗结蛋白抗体对足细胞的染色比对其他任何细胞都更强烈。细胞角蛋白和波形蛋白染色无法区分足细胞与其他细胞类型。这些发现表明，在高等脊椎动物中，足细胞的特征是强烈的波形蛋白染色，而在低等脊椎动物中则是结蛋白染色，这表明这些组中足细胞的IF蛋白可能具有独特的生理功能。
