靶向OX40基因的siRNA抑制大鼠肝脏移植排斥反应的研究

目的 探讨RNA干扰阻断OX40-OX40L共刺激通路对大鼠移植肝存活时间的影响.方法 制作原位肝脏移植物大鼠模型,供体DA大鼠,受体Lewis大鼠.移植术毕时将5 ml含5×109pfu的pLVTHM-OX40-siRNA重组慢病毒经阴茎背静脉在10秒内注射受鼠体内,术后观察受鼠存活时间,移植肝脏进行组织病理学检查,采用ELISA法检测大鼠外周血IL-2、IFN-γ的水平,并进行受者大鼠脾细胞对供者大鼠脾细胞的混和淋巴细胞反应(MLR). 结果转染组大鼠肝脏移植物的存活时间为(74.0±9.3)d,明显长于对照组(7.3±0.5)d和未转染组(7.5±0.5)d;转染组移植肝组织炎细胞浸润、间质水肿、肝组织坏死程度较对照组和未转染组减轻;耐受组大鼠脾脏中T淋巴细胞刺激T淋巴细胞增殖的能力较对照组降低(t=25.1,P＜0.01);移植术后第7 d,转染组血清IL-2浓度为(46±8.4)pg/ml,IFN-γ浓度为(202.7±14.6)pg/ml,均显著低于对照组和未转染组(分别t=176.4,45.5,P＜0.01).结论 转染靶向OX40的siRNA,可通过阻断OX40-OX40L共刺激通路,抑制大鼠肝脏移植后的排斥反应,延长大鼠移植肝的存活时间.

Prolonged rat liver allograft survival by in vivo targeting OX40-siRNA OX40-OX40L co-stimulatory cascade blockade

Objective To investigate the effect of blockading OX40-OX40L co-stimulatory signaling on the survival time of liver allograft in rat.Methods siRNA-expression vectors were constructed to targeting OX40.3～5 minutes before DA to Lewis orthotopic liver transplantation was performed,5×109 pfu of targeting OX40 siRNA plasmid DNA were diluted in 5 ml of phosphate buffered saline(PBS)and inlected intravenously into recipient Lewis rat over a period of 10 seconds.Serum IL-2 and IFN-γ levels were assayed by ELISA,and mix lymphocyte response(MLR)were tested by 3H-thymidine.Results The survival time of recipients in siRNA treatment group(74.0±9.3)was significantly longer than that in control group[(7.3±0.5)days].In experiment group,the inflammatory cell infihration and liver tissue structure destruction were very slight.The concentration of serum IL-2 was much lower in siRNA treatment group[(46±8.4)pg/ml]than that in control group[(286.5±14.6)pg/ml].Meanwhile,the concentration of serum IFN-γ was much lower in siRNA treatment group [(202.7±14.6)pg/ml]than that in control group[(1682.7±87.9)pg/ml].Conclusion Administration of OX40-siRNA can blockade OX40-OX40L co-stimulatory signaling pathway.hence inhibit the rejection of liver allograft.