RGC-32在儿童IgA肾病肾组织中的表达及意义

目的 研究RGC-32（response gene to complement 32）在IgA肾病(IgAN) 儿童及正常肾组织中的表达及其意义。 方法 用免疫组织化学方法观察IgAN儿童及正常肾组织中RGC-32蛋白的表达与分布，并与α平滑肌肌动蛋白(α-SMA)、转化生长因子β1（TGF-β1）的表达、IgAN肾组织病理损伤程度及临床相关指标进行统计学分析。 结果 RGC-32蛋白在IgAN及正常肾组织的肾小管均明显表达，而在肾小球、肾小管间质及肾血管未见表达。RGC-32 在正常肾组织、IgAN轻度、中度及重度损伤组中的阳性表达指数分别为（18.29±6.22）%、（23.90±9.65）%、（31.23±9.86）%和（34.52±10.63）%。RGC-32在IgAN儿童肾组织的阳性表达指数与肾小球评分、肾小管间质评分均呈正相关（r = 0.385，0.347，P < 0.05）；与α-SMA、TGF-β1表达亦呈正相关（r = 0.594，0.521，P < 0.01）；而与Scr、尿NAG/Cr、尿Alb/Cr、尿 IgG/Cr、尿α1微球蛋白/Cr均无相关（r = 0.117，-0.115，-0.138，-0.176，-0.028，P均>0.05)。 结论 首次发现RGC-32蛋白在IgAN儿童和正常肾组织中表达于肾小管，而在肾小球、肾小管间质及肾血管未见表达。RGC-32可能参与了IgAN患儿的肾小管间质损伤，尤其是TGF-β1诱导的肾小管上皮细胞-间充质转分化（EMT）过程。

Expression of response gene to complement 32 in renal tissue of children with IgA nephropathy and its significance

Objective To examine the expression of response gene to complement 32 (RGC-32) in renal tissue of children with IgA nephropathy (IgAN), and to explore its significance. Methods The subjects were 45 children diagnosed as IgAN by renal biopsy. The expression of RGC-32, α-smooth muscle actin (α-SMA) and transforming growth factor β1 (TGF-β1) was examined by immunohistochemistry staining. The correlation of RGC-32 expression with α-SMA,TGF-β1, degree of renal pathological lesions and clinical index in IgAN was assessed by Spearman correlation analysis. Results RGC-32 protein located in renal tubular epithelial cells in normal and IgAN renal tissues. The positive expression index of RGC-32 in nomal group, IgAN mild group, moderate group and severe group was (18.29±6.22)%, (23.90±9.65)%, (31.23±9.86)%,and (34.52±10.63)% respectively. With more severity of renal pathological lesions, the expression of RGC-32 in IgAN was enhanced. The RGC-32 expression was positively correlated with the score of glomerulus and renal interstitium in children with IgAN (r=0.385, 0.347, P＜0.05), as well as α-SMA, TGF-β1 (r=0.594, 0.521, P＜0.01), but was not correlated with Scr, urinary NAG/Cr,Alb/Cr, IgG/Cr, and α1-M/Cr (r =0.117, -0.115, -0.138, -0.176, -0.028, all P ＞0.05).Conclusions RGC-32 protein locates in renal tubular epithelial cells in normal and IgAN renal tissues. RGC-32 may participate in the course of renal tubulointerstitial lesions in children with IgAN, especially in the course of epithelial-mesenchymal transition (EMT) induced by TGF-β1.