狼疮肾炎患者Ⅰ型干扰素诱导基因表达的研究

目的 了解Ⅰ型干扰素(IFN)诱导基因IFIT4、IFI44、Ly6e、OAS1、OAS2和OAS3在狼疮肾炎(LN)患者的表达,并分析IFN积分与临床特征之间的相关性.方法 ①同步收集12例弥漫增生型LN患者.肾组织和外周血,抽提总RNA并反转录为cDNA,以实时荧光定量聚合酶链反应(PCR)方法检测Ⅰ型IFN诱导基因IFIT4、IFI44、Ly6e、OAS1、OAS2和OAS3的表达水平.②收集119例LN患者的临床资料,计算每例患者的IFN积分,并与系统性红斑狼疮疾病活动指数(SLEDAI)积分、抗dsDNA抗体、补体、蛋白尿水平等指标进行相关性检验.结果 ①弥漫增生型LN患者肾组织高表达OAS2(1.46±1.15)与(0.60±0.59)]和OAS3(2.16±1.63)与(0.93±0.95)],P<0.05;IFIT4(1.68±1.76)与(0.96±0.71)]、IFI44(3.23±2.67)与(1.65±1.95)]、Ly6e(3.54±2.09)与(2.34±2.57)]、OAS1(2.52±1.86)与(1.34±0.28)]的表达量高于对照组1个循环左右.狼疮患者外周血高表达IFIT4(11.2±7.7)与(1.56±2.71)]、IFI44(9.5±6.1)与(2.6±4.4)J、Ly6e(17.5±13.7)与(7.1±10.3)]、OAS1(8.68±6.36)与(1.15±1.89)]、OAS2(10.41±7.71)与(0.66±0.82)]、OAS3(8.75±4.34)与(0.89±1.34)],P<0.05.Ⅰ型IFN诱导基因IFIT4、IFI44、Ly6e、OAS1、OAS2和OAS3在肾脏组织和外周血的表达呈同步增高趋势.②根据119例患者IFIT4、IFI44、Ly6e、OAS1、OAS2和OAS3的表达计算IFN积分,发现IFN积分与SLEDAI、抗dsDNA抗体呈正相关(r分别是0.216和0.394,P<0.05),与血清补体水平呈负相关(r=0.315,P<0.01).结论 Ⅰ型IFN诱导基因IFIT4、IFI44、Ly6e、OAS1、OAS2和OAS3外周血表达的水平在一定程度上反映LN肾损害情况,IFN积分对监测LN患者的疾病活动有一定的特异性.

Association of increased interferon-inducible gene expression with disease activity in patients with lupus nephritis

Objective To study 6 type Ⅰ interferon (IFN)-inducible genes (IFIT4, IFI44, Ly6e,OAS1, OAS2 and OAS3) in patients with lupus nephritis (LN) and analyze its correlated expression levels with disease activity and/or clinical manifestations. Methods Total RNA was obtained simultaneously from kidney tissues and peripheral blood cells of 12 patients with diffuse proliferative lupus nephritis and 10 normal controls. Moreover, peripheral blood cells were obtained from 119 LN patients and 35 normal controls. Total RNA was extracted and reversely transcribed into complementary DNA. Gene expression levels were measured by real-time polymerase chain reaction by comparing to a housekeeping gene, and IFN score was calculated. Disease activity was determined by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Results The 6 genes were highly expressed in diffuse proliferative lupus nephritis patients compared with normal controls. IFN scores were positively correlated with SLEDAI score, the concurrent presences of anti-double-stranded DNA (anti-dsDNA) antibodies (P<0.05) and hypocomplementemia (P<0.01). Conclusion The 6 IFN-inducible genes are highly expressed iri LN patients. IFN scores are elevated in active lupus nephritis patients, in patients with positive anti-ds-DNA antibody and hypocomplementemia. IFN scores may be a useful biomarker for lupus nephritis therapy.