Expression of Nestin in the Rat Kidney with Ischemia-Reperfusion Injury

Choi, Jae Youn; Kim, Jin; Cha, Jung Ho

Abstract

Nestin, a type VI intermediate filament,is a marker for stem cells.Although it is expressed abundantly in various organs during development,its expression in adults is restricted to certain types of cells.However,nestin is reinduced in activated cells involved in the regeneration and survival of injured tissues.We investigated the expression of nestin in the ischemia-reperfusion injured rat kidney by immunohistochemistry using anti-nestin antiserum. Kidneys were preserved from normal adults and at 1,3,5,7 and 14 d after ischemia-reperfusion injury,and processed using pre-embedding.In the normal adult kidney,nestin was expressed strongly in the glomerular podocyte.Capillary endothelial cells,except for those of the glomeruli,showed nestin positivity.Fibroblast-like interstitial cells were also nestin positive except for lipid-laden interstitial cells of the inner medulla.After ischemia-reperfusion injury,the renal expression of nestin increased progressively to 7 d and then returned almost to a normal level by 14 d.These changes of nestin expression were attributed mainly to changes in the number and staining intensity of immunostained interstitial cells.The podocytes and endothelial cells showed no change in immunoreactivity throughout any stage in the experimental animals.Interestingly,nestin-positive tubular cells,which were nestin negative in normal kidney,were observed from 3 to 14 d.Nestin immunostained cells were increased in the interstitium around these nestin-positive tubules.These results suggest that nestin is induced in both interstitial cells and regenerating tubular cells and that it can be used as a histological marker related to epithelial-mesenchymal transformation in the injured kidney.