白细胞介素17在IgA肾病肾小管间质的表达及意义

目的观察白细胞介素17（IL-17）在IgA肾病患者肾组织的表达，探讨IL-17在IgA肾病中的临床及病理意义。方法选择51例IgA肾病患者肾组织活体检查采用Katafuchi半定量积分标准和免疫组织化学技术进行病理学积分和检测IL-17的表达，同时检测51例IgA肾病患者中30例外周血单个核细胞（PBMCs）中IL-17、转化生长因子β1（TGF-β1）、IL-6、IL-23、IL-βmRNA的表达。结果正常肾组织中未见IL-17表达。51例IgA肾病患者中，21例肾小管上皮细胞胞质IL-17表达阳性，2例肾间质淋巴细胞IL-17表达阳性，总阳性率为45．10％；并且随着肾小管间质病变加重，IL-17的表达逐步增多。IgA肾病患者PBMCs中IL-17、IL-6、IL-23、IL-1βmRNA的表达较正常人显著升高（P〈0．01），TGF-β1mRNA的表达与正常人比较无统计学差异（P〉0．05），IL-17mRNA与TGF-β1、IL-β1mRNA的表达呈正相关（r=0．67、0．71，P〈0．05）。IgA肾病患者肾小管间质IL-17的表达水平与尿位相畸形红细胞计数、肾小管间质病理积分呈正相关（r=0．60、0．67，P〈0．05），IL-17mRNA的表达与血肌酐呈正相关（r=0．66，P〈0．05）。结论IgA肾病患者肾小管间质及外周血中IL-17表达增高，并与临床及病理预后指标密切相关，提示IL-17可能是参与IgA肾病发病及进展的因素之一。

Significance of interleukin 17 expression in renal tubulointerstitium of IgA nephropathy patients

Objective To detect the expression of interleukin 17 （IL-17） in renal tissue of pa- tients with IgA nephropathy and investigate the clinicopathologic significance of IL-17 in IgA nephropathy. Methods IL-17 expression was detected in 51 renal biopsy samples of IgA nephropathy patients by immunohistochemistry. The biopsy samples were scored by using the pathological scoring system described by Katafuchi. Real-time PCR was performed to analyze the expression of IL-17,TGF-β1, IL- 6, IL-23,IL-1β mRNA in peripheral blood mononuclear cells （PBMCs） of 30 among the 51 cases of IgA nephropathy. The possible correlations between IL-17 expressions and the clinicopathologic chan- ges were evaluated. Results IL-17 was predominantly detected in cytoplasm of tubular epithelial cells of 21 patients with IgA nephropathy and IL-17 positive lymphocytes infiltration was found in 2 cases of IgA nephropathy. The total IL-17 positive rate was 45. 10% in patients with IgA nephropathy whereas no IL-17 expression was observed in normal kidney samples. As the tubulointerstitial pathological score was elevated, renal IL-17 expression was increased consistently. IL-17,IL-6,IL-23 and IL-1t3 mRNA levels were significantly higher （P〈0. 01） in PBMCs of IgA nephropathy patients than those in healthy controls, but there were significant difference in TGF-β1 mRNA levels between the two groups （P〈0. 05）. The expression levels of IL-17 mRNA were positively correlated with those of TGF-β1 and IL-1β mRNA respectively （r= 0. 67, 0. 71, P〈0. 05）. Correlation analysis revealed that in IgA nephropathy patients, renal IL-17 expression was positively correlated with urine dysmorphic RBC count and the tubulointer-stitial score （r= 0. 60,0. 67,P〈0. 05）, and IL-17 mRNA levels were positively correlated with serum creatinire （r = 0. 66, P〈0. 05）. Conclusions The aberrant increase of IL-17 expression in IgA nephropathy patients and its correlation with the clinicopathologic prognostic indicators suggest that IL-17 might play a critical role in the pathogenesis and progression of IgA nephropathy.