大鼠肾移植后抗波形蛋白抗体升高与慢性移植肾肾病的相关性

Antivimentin antibody in rats with chronic allograft nephropathy

目的研究大鼠肾移植术后抗波形蛋白抗体的表达水平与慢性移植肾肾病（CAN）的相关性，以及不同免疫抑制剂对其的影响。方法选取近交系F344大鼠作为同系肾移植的供、受者（共9对），选取F344和Lewis大鼠分别作为同种肾移植的供、受者（共27对）。同系移植组受者术后不给予免疫抑制剂；同种移植组受者术后10d内给予环孢素A（CsA），然后将同种移植组受者随机平均分为生理盐水（NS）组、CsA组和霉酚酸酯（MMF）组（每组9只），分别给予NS、CsA和MMF灌胃。术后第4、8和12周时分别处死每组受者3只，观察CAN的进展、波形蛋白及其基因的表达以及抗波形蛋白抗体的水平，取正常大鼠（包括F344和Lewis大鼠）作为对照。结果观察期内同系移植组未发生CAN；而同种移植组发生了CAN，且不断加重，其中CsA组和NS组的CAN病理改变非常明显，而MMF组明显较轻。术前所有受者血清中均未检测到抗波形蛋白IgM和IgG抗体，术后也未检测到抗波形蛋白IgM抗体；术后同系移植组仅检测到微量的抗波形蛋白IgG抗体，同种移植组检测到大量的抗波形蛋白IgG抗体。随着CAN的进展，同种移植中，CsA组和NS组血清抗波形蛋白IgG抗体的水平逐渐增高，而MMF组抗体水平的增高显著低于NS组（P〈0．05），但仍显著高于同系移植组（P〈0．05）。结论大鼠同种肾移植术后，受者体内可产生抗波形蛋白IgG抗体，且产生的时间早于CAN，抗波形蛋白IgG抗体水平也会随着CAN的进展而增高。MMF可抑制抗波形蛋白IgG抗体的产生，CsA无此作用。

Objective To investigate the expression of antivimentin in rats after renal transplantion, its relationship with chronic allograft nephropathy （CAN） and the curative effectiveness of different imrnunosuppressants. Methods Renal transplantation was performed by using F344 rats as both donors and recipients in isograft group. F344 and Lewis rats were used as donors and recipients respectively in allograft group. Allograft recipients were first treated with cyclosporine A （CsA, 10 mg.kg^-1·day^-1 for 10 days） and then divided into 3 groups （each n = 9） ： vehicle group, CsA （6 mg.kg^-1·day^-1）-treated group and mycophenolate （MMF） （20 mg.kg^-1·day^-1）-treated group. Blood was taken before and at 4th, 8th and 12th week after operation. The rats were sacrificed and the renal iso- and allografts were harvested. The serum creatinine was determined, and pathological changes were analyzed according to Banff 97 criteria. The levels of vimentin were detected and localized by quantitative RT-PCR and immunohistochemistry, and the levels of vimentin antibodies （IgM, IgG） were analyzed by using ELISA. Results Both antivimentin IgM and IgG were not found in the sera of all recipient rats before transplantation, and no IgM was found in the sera of all recipient rats after transplantation. A trace of antivimentin IgG was detected in the sera of rats receiving isografts while IgG was evident in the rats receiving allografts. At 4th week, CAN was not obvious in 3 allograft groups. The IgG levels in vehicle, CsA-treated and MMF-treated groups were 0. 173 ± 0. 016, 0. 174±0. 026 and 0. 141 ± 0. 007, respectively （P〉0. 05）. Along with progression of CAN （Banff Score 5.33± 0. 58 and 12. 57± 1.16 in vehicle group at 8th and 12th week, respectively,P = 0. 001）, the levels of IgG in vehicle group was increased gradually （0. 235± 0. 014, 0. 285± 0. 019, at 8 th, 12 th week, P = 0. 009 ）. CsA did not prevent the formation of IgG （ 0. 233 ± 0. 020 , 0. 274 ±0. 029） and the progression of CAN （4. 67 ± 1.53, 13. 33 ± 1.53） at 8th, 12th week. Meanwhile, MMF could significantly decrease the formation of IgG and the progression of CAN. Conclusions The antivimentin antibody （IgG） is produced in the rats with renal allografts. The formation of antivimentin antibody is earlier than the development of CAN and its levels are increased along with the progression of CAN. MMF can suppress the production of antivimentin antibody, while CsA has no this effect.