TNF-α siRNA表达载体的构建及其对胶原性关节炎大鼠TNF-α及IL-1的影响

Construction of TNF-α siRNA Expression Vector and its Therapeutic Effect on TNF-α and IL-1 in Type Ⅱ Collagen Induced Arthritis Rat

目的观察肿瘤坏死因子(TNF)-α的小干扰RNA(siRNA)真核表达载体对胶原性关节炎(CIA)大鼠的治疗作用。方法构建TNF-α的siRNA真核表达载体并注射CIA大鼠,随机分为模型组、空载体组、TNF-α-siRNA1组和TNF-α-siRNA2组,每组6只,各组分别尾静脉注射磷酸盐缓冲液(PBS)、pGFP-V-RS空载体、TNF-α-siRNA1真核表达载体和TNF-α-siRNA2真核表达载体。另设6只未造CIA模型只注射PBS的大鼠为空白组。于注射后1、5、9和13 d采血,ELISA检测血清中IL-1的变化;注射后13 d处死大鼠,RT-PCR检测TNF-αmRNA的表达水平。结果注射第1、5、9和13天模型组大鼠血清中IL-1的表达水平高于空白组(P<0.05),注射第1、5和9天TNF-α-siRNA1组和TNF-α-siRNA2组IL-1的表达水平低于模型组和空载体组(P<0.05);注射后第13天模型组大鼠全血中TNF-αmRNA的表达水平明显高于空白组(P<0.05),TNF-α-siRNA1组和TNF-α-siRNA2组mRNA表达水平低于模型组和空载体组(P<0.05)。结论TNF-α的特异性siRNA能抑制TNF-αmRNA和IL-1的表达水平,从而为类风湿关节炎的基因治疗提供实验依据。

Objeαive To investigate the therapeutic effeα of tumor necrosis faαor （TNF）-α siRNA on type II colla- gen induced arthritis （CIA） in rats. Methods The expression veαors of siRNA against TNF-α gene were construαed suc- cessfully and were injeαed by tail veil into CIA rats. Twenty-four CIA rats were randomly divided into 4 groups including model group, empty veαor group, TNF-α-siRNA1 group and TNF-α-siRNA2 group. CIA rats were injeαed with the same dose of phosphate buffered sodium （PBS） and pGFP-V-RS veαor respeαively in model group and empty veαor group, while TNF-α-siRNA1 group and TNF-α-siRNA2 group were injeαed with TNF-α-siRNA1 eukaryotic expression veαor and TNF-α-siRNA2 eukaryotic expression veαor respeαively. Another 6 rats, which were not established CIA model, were in- jeαed with PBS （blank control group）. The serum expression levels of IL-1 were deteαed by ELISA on day l, 5, 9 and 13 af- ter injeαion. The expression level of TNF-c~ mRNA was deteαed by reverse transcriptase polymerase chain reaαion （RT- PCR） on day 13. Results The expression level of IL-1 was significantly higher on day l, 5, 9 and 13 in model group than that of blank group （P〈0.05）. The expression levels of IL- 1 were significantly lower on day 1, 5 and 9 in TNF-c^-siRNA1 group and TNF-α-siRNA2 group than that of model group and blank group （P 〈 0.05）. The expression level of TNF-α mRNA was significantly higher on day 13 in model group than that of blank group （P 〈 0.05）. The expression levels of TNF- α mRNA were significantly lower in TNF-a-siRNA1 group and TNF-α-siRNA2 group than those of model group and emp- ty veαor group （P 〈 0.05）. Conclusion TNF-α specific siRNA can suppress the levels of TNF-α mRNA and IL-1, which provides experimental basis for gene therapy of rheumatoid arthritis.