Bollain-Y-Goytia J J, González-Castañeda M, Torres-Del-Muro F, Daza-Benitez L, Zapata-Benavides P, Rodríguez-Padilla C, Avalos-Díaz E, Herrera-Esparza R
Department of Immunology, UABE, University of Zacatecas (UAZ), Zacatecas, México.
Indian J Nephrol. 2011 Jul;21(3):166-71. doi: 10.4103/0971-4065.83029.
Podocytes are highly specialized epithelial cells that form part of the filtration barrier in the kidney, and their loss reflects a malfunction in glomerular filtration, which is usually associated with the progression of the disease. Glomerulonephritis is a serious complication that develops in about 50% of the lupus patients and is characterized by proteinuria arising from direct or indirect podocyte injury. To assess the possible role of podocytes in the pathogenesis of lupus nephritis (LN). Urinary and glomerular podocytes were detected in the kidney biopsies of patients (n = 17) with lupus nephritis, and from control biopsies obtained during autopsies. The WT-1 protein was used as a podocyte marker. The cumulative excretion of urinary podocytes was detected in the urinary sediments of LN patients and normal healthy controls, and the specimens were analyzed by immunohistochemistry, immunofluorescence, and enzyme-linked immunosorbent assay. The apoptotic index was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. Gross proteinuria in lupus patients was determined via 24-hour urine samples, and the results were analyzed by Student t test. Biopsy specimens from 17 patients with class-III or IV LN had lower levels of glomerular WT-1 expression than the levels found in normal kidneys (P < 0.0001). The reduction of glomerular podocytes in patients with lupus nephritis correlated with the cumulative excretion of urinary podocytes (P < 0.0001) and proteinuria. There was no correlation between the urinary podocytes and the apoptotic index in the LN urinary sediments. A decrease in glomerular podocytes is associated with their cumulative excretion in urinary sediments; therefore, such findings correlate with proteinuria in lupus nephritis patients.
足细胞是高度特化的上皮细胞，构成肾脏滤过屏障的一部分，其丢失反映肾小球滤过功能异常，这通常与疾病进展相关。肾小球肾炎是一种严重并发症，约50%的狼疮患者会发生，其特征是直接或间接的足细胞损伤导致蛋白尿。为评估足细胞在狼疮性肾炎（LN）发病机制中的可能作用。在狼疮性肾炎患者（n = 17）的肾活检组织以及尸检获得的对照活检组织中检测尿液和肾小球足细胞。WT-1蛋白用作足细胞标志物。在LN患者和正常健康对照者的尿沉渣中检测尿足细胞的累积排泄量，并通过免疫组织化学、免疫荧光和酶联免疫吸附测定法对标本进行分析。通过末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法测定凋亡指数。通过24小时尿样测定狼疮患者的总蛋白尿，并采用Student t检验分析结果。17例III级或IV级LN患者的活检标本中肾小球WT-1表达水平低于正常肾脏（P < 0.0001）。狼疮性肾炎患者肾小球足细胞的减少与尿足细胞的累积排泄量（P < 0.0001）和蛋白尿相关。LN尿沉渣中的尿足细胞与凋亡指数之间无相关性。肾小球足细胞减少与其在尿沉渣中的累积排泄有关；因此，这些发现与狼疮性肾炎患者的蛋白尿相关。
