MRL/lpr鼠部分病理指标动态变化及SIGIRR表达与狼疮肾炎相关性研究

Dynamic change of pathological indexes in MRL/lpr mice and the research of relationship between lupus nephritis and SIGIRR expression

目的观察MRL/lpr鼠病理指标动态变化,研究MRL/lpr小鼠肾组织单个免疫球蛋白区白介1相关受体(single Ig IL-1-related receptor,SIGIRR)的表达是否随病理分级加剧而变化,以提示TLR4/NF-κB通路是否参与了狼疮肾炎(iupus nephritis,LN)的发生发展。方法对照组C57BL/6小鼠和模型组MRL/lpr小鼠各12只,分别检测12、15、18、21周龄时小鼠胸腺指数、脾指数、尿蛋白,血清尿素氮(blood urea nitrogen,BUN)、抗核抗体(antinuclear antibodies,ANA);对肾组织切片进行苏木素依红(hematoxylin and eosin,HE)和马松(Masson)染色,观察模型鼠狼疮肾炎发病情况,采用免疫印迹(western blot)和免疫组化(immunohistochemistry,IHC)方法观察不同周龄小鼠肾脏SIGIRR的表达情况。结果 MRL/lpr小鼠12、15、18、21周龄时与同龄C57BL/6鼠相比其尿蛋白水平随周龄增加而升高,血清尿素氮以及抗核抗体和对照组相比无明显差异,HE、Masson染色显示模型鼠从12周开始即表现出肾小球肾炎,血管周围炎细胞浸润,之后逐渐间质纤维化,肾小球系膜和基底膜增厚,甚至出现肾小球纤维化和硬化。Western blot和IHC结果显示,21周龄时MRL/lpr小鼠肾组织SIGIRR蛋白表达增加,与同龄C57BL/6相比有显著性差异。结论 SIGIRR蛋白表达随MRL/lpr小鼠狼疮肾炎加重而增加,其可能与TLR4/NF-κB(Tolllike receptor 4/nuclear factor-kappa B,Toll样受体4/核因子κB)通路相关。

Objective To observe the dynamic change of pathological indexes in MRL/lpr mice and explore the relationship between expression of SIGIRR in kidney tissue and the pathological grade of lupus nephritis, which suggested whether TLR4/NF-κB signal pathway was involved in the development of LN. Methods There were 12 control mice C57BL/6 and 12 model mice MRL/lpr and then their thymus and spleen index,proteinuria,BUN,ANA were detected at 12week,15week,18week and 21week respectively. And kidney frozen sections were stained with HE and Masson to study the pathological grade of LN. At last, IHC and western blot was used to analyze the expression of SIGIRR in kidneys of mice at different ages. Results Proteinuria of MRL/lpr mice increased from 12week to 21week when compared with control mice at the same age, while BUN and ANA had no significant increase as time went by. HE and Masson staining showed that model mice began to develop glomerulonephritis, diffuse infiltration of inflammatory cells surrounding vessels at 12 week, and then kidney interstitial fibrosis, Glomerular mesangial and basement membrane thickening, and even the glomerular fibrosis and sclerosis. However expression of SIGIRR in kidney of MRL/lpr mice at 21 week had significant increase when compared with that of C57BL/6 mice by western blot and IHC. Conclusion Expression of SIGIRR increased following the LN development, and it may be involved in the TLR4/NF-κB signal pathway.