CpG-ODN对肾小球肾炎进展的影响

Effect of CpG-ODN on Progression of Glomerulonephritis

目的观察CpG-ODN对肾小球肾炎进展的影响。方法将Wistar雄性大鼠随机分为N组(正常对照)、M组(模型对照)、CpG组和GpC组。N组大鼠经尾静脉注射生理盐水2.5ml/(kg·d),其余3组大鼠经尾静脉注射抗-thy1.1单克隆抗体2.5ml/(kg·d),隔日1次,共3次。注射抗-thy1.1单克隆抗体后,隔天,CpG组经尾静脉注射CpG-ODN,300μg/只,GpC组经尾静脉注射GpC-ODN,300μg/只,隔日注射,共3次。各组大鼠分别于用药前和第1针注射后1周测定尿蛋白;用药后第8周留取大鼠24h尿、血清及肾脏组织,检测24h尿蛋白定量、血清白蛋白和肾功;肾脏组织用于肾脏病理检查以及RT-PCR法检测TLR-9mRNA的表达。结果CpG组与M组和GpC组相比,血清白蛋白含量明显降低,且差异有显著意义;M组、CpG组和GpC组在给药后1周均出现尿蛋白,在给药后8周,24h尿蛋白含量明显增多;CpG组与M组相比,TLR-9mRNA在肾脏的表达水平明显增加,且差异有显著意义;GpC组与M组相比,差异无显著意义;光镜下可见CpG组肾组织病理改变明显加重。结论天然CpG-ODN可促进肾小球肾炎病情加重,TLR-9可能在其发生机理中起重要作用。

Objective To observe the effect of CpG-ODN on progression of glomerulonephritis. Methods Inject i.v. male Wistar rats with anti-thy1.1 McAb at a dosage of 2. 5 ml/（kg·d） every other day for 3 times to establish the rat model of glomerulonephritis. Divide the model rats into model control（M）, CpG and GpC groups randomly. The rats in CpG and GpC groups were injected with CpG-ODN and GpC-ODN respectively every other day for 3 times, each at a dosage of 300 μg, and those in M group were uninjected. Set normal rats as a normal control （N） group and inject with 2. 5 ml/（kg·d） of physiological saline. The rats were tested for urinary protein before and 1 week after the 1st injection, and for 24-hour urinary protein excretion, serum albumin and renal function 8 weeks after the 1st injection. The kidney tissues of rats 8 weeks after the 1st injection were collected for pathological examination and test for expression of Toll-like receptor-9 （TLR-9） mRNA by RT-PCR. Results The serum albumin level of CpG group was significantly lower than those of M and GpC groups. Urinary proteins were detected in M, CpG and GpC groups 1 week, and the 24-hour urinary protein excretions increased significantly 8 weeks after the 1st injection. The expression level of TLR-9 mRNA in kidneys of rats was significantly higher in CpG group than that in M group, while showed no significant difference between GpC and M groups. Light microscopy showed that the pathological change of kidney tissue in CpG group increased significantly as compared with the other 3 groups. Conclusion Natural CpG-ODN promoted the progression of glomerulonephritis, in which TLR-9 might play an important role.