成纤维细胞特异性蛋白-1在急性肾小管坏死病变中的表达及临床意义

目的检测成纤维细胞特异性蛋白-1(FSP-1)在急性肾小管坏死(ATN)病变肾组织及尿沉渣中的表达,并分析其临床意义。方法收集ATN患者10例,新月体肾炎2例为阳性对照,正常肾组织3例为阴性对照,采用免疫组化和免疫荧光法检测FSP-1、CD68(巨噬细胞标志物)在肾组织中的表达,并观察ATN患者尿沉渣涂片中FSP-1的表达。收集6例健康志愿者的晨尿标本作为阴性对照。结果正常肾组织肾间质小血管偶见FSP-1表达,CD68染色阴性。阳性对照新月体肾炎患者肾小球细胞性新月体及纤维细胞性新月体中FSP-1呈散在阳性分布,肾小管间质中亦可见FSP-1阳性细胞。ATN患者肾组织FSP-1阳性细胞位于损伤、再生的肾小管周围及肾小管管腔中,部分肾小管上皮细胞也见FSP-1阳性表达。肾组织病变严重的ATN患者肾脏及尿沉渣涂片中FSP-1阳性细胞明显增多。尿沉渣FSP-1阳性细胞数与肾脏FSP-1阳性细胞数呈正相关(r=0.793,P=0.006)。FSP-1与CD68的阳性表达部位不重叠。健康志愿者的尿沉渣涂片中未见FSP-1阳性细胞表达。结论 ATN患者肾组织中可见FSP-1阳性细胞的浸润及FSP-1在肾小管上皮的表达,与尿沉渣FSP-1阳性细胞数呈正相关,FSP-1有望成为反映肾小管急性损伤的生物学标志物。

Clinicopathologic significance of fibroblast-specific protein-1 in acute tubular necrosis

Objective To investigate the immunolocalization and clinical significance of fibroblast-specific protein-1 （FSP-1） in renal tissues and urinary sediment of acute tubular necrosis （ATN） patients. Methods We collected renal tissues and urinary sediments of ATN patients （n=10）. We chose renal tissues of crescent nephritis （n=2） as positive control of FSP-1 and normal renal tissue （n=3） as negative control. We also choose urinary sediments of six healthy volunteers as negative controls. Renal localization of FSP-1 and CD68 （marker of macrophage） were detected by immunohistochemistry and immunofluorescence. Expression of FSP-1 in urinary sediments was detected by immunofluorescence. Results In normal kidney, FSP-1 was occasionally expressed in small vessels of tubulointerstitial tissue and staining of CD68 was negative. In crescent nephritis, FSP-1 was expressed in cellular crescent and fibrous-cellular crescent; FSP-1 positive cells were also expressed in tubulointerstitial tissue of crescent nephritis. In ATN, FSP-1 positive cells were expressed in tubular lumen and tissues surrounding damaged tubules and regenerated tubules. Some tubular epithelial cells also expressed FSP-1. FSP-1 positive cells were also found in urinary sediments of ATN patients. There were more renal and urinary sediment FSP-1 positive cells in patients with more severe interstitial lesion. The number of renal FSP-1 positive cells was positively correlated with that of FSP-1 positive cells in urinary sediment （r=0.793, P=0.006）. There was no expression of FSP-1 positive cells in urinary sediments of healthy volunteers. FSP-1 positive cells did not stain with CD68. Conclusion With FSP-1 positive cells infiltration and FSP-1 expression in some tubules, and the number of renal FSP-1 positive cells were correlated with that of FSP-1 positive cells in urinary sediment, FSP-1 might be a biomarker of acute tubular injury in ATN.