慢性排斥肾移植大鼠继发对自身组织蛋白vimentin的细胞和体液免疫反应

摘要

目的:研究慢性排斥肾移植受体对自身组织抗原--波形蛋白（vimentin）的细胞和体液免疫反应.方法:近交系Lewis大鼠接受F344大鼠供肾行左侧原位肾移植,7天后对侧肾切除,建立肾移植慢性排斥反应模型.术后每2周检测受体蛋白尿水平,术后第49天与98天取供肾作病理检查,观察慢性移植肾肾病（CAN）进程.术后第14、49、98天收获受体脾细胞,以酶联免疫斑点法（ELISPOT）检测vimentin特异性IFNγ分泌T细胞的数量；收获受体血清以酶联免疫吸附法（ELISA）检测vimentin特异性抗体水平.自体肾移植Lewis大鼠持续行肾功能检测,第98天收获肾脏、脾脏、血清作病理及免疫检测.结果:同种肾移植受体蛋白尿水平在6周后逐渐升高,49天时病理检查发现肾间质纤维化、肾小管萎缩等典型CAN病变,CAN病情逐渐加重.而自体肾移植大鼠术后98天蛋白尿水平无改变,无CAN病变.经体外vimentin特异性刺激,同种肾移植大鼠IFNγ分泌T细胞的数量在肾移植后49天明显增多（28.3±2.0 vs.10.1±2.1）,98天时其数量显著上升（126.0±10.4 vs.26.3±4.1,P＜0.01）.而自体肾移植大鼠vimentin特异性IFNγ分泌T细胞数量无明显变化.同种肾移植大鼠vimentin特异性抗体水平术后14天即显著升高（0.230±0.018 vs.0.063±0.008,P＜0.05）,并维持在较高水平.而自体肾移植大鼠vimentin特异性抗体水平无明显改变.结论:慢性排斥肾移植受体继发针对自身抗原vimentin的细胞与体液免疫反应,继发自身免疫可能参与CAN的发展.%Objective: To investigate the cellular and humoral immune responses against autoimmune tissue antigen vimentin in allograft rat recipients undergoing chronic rejection. Methods: Chronic rejection model of allograft kidney was established that the left kidney of Lewis was replaced by a F344 allograft and a contralateral nephrectomy was performed 7 days later. Proteinuria changes of recipients were observed every 2 weeks post-transplantation. The rats were sacrificed at 14th, 49th and 98th day after operation, and the renal grafts, spleens and serums were harvested. Light microscopic examination of kidney lesions was performed. The frequencies of specific IFN-γ secreting T cells in presence of vimentin were detected by ELISPOT assay, and the levels of vimentin IgG antibodies were analyzed by ELISA. Syngenic transplants Lewis rats were persisted in proteinuria measurement, and the renal grafts, spleens and serums were examined at 98th day after operation. Results:In the allograft recipients, in parallel to the proteinuria increasing, the interstitial fibrosis and tubular atrophy of kidneys with chronic allograft nephropathy ( CAN ) was developing from day 49. No proteinuria increasing and CAN were emerged in syngenic transplants at day 98. The number of vimentin-specific IFN-7 secreting T cells began to increase at day 49 ( 28. 3 ± 2.0 vs. 10. 1 ± 2. 1 ) in the allograft recipients, and significantly increased at day 98 ( 126. 0 ± 10. 4 vs. 26. 3 ±4. 1, P <0. 01 ). But in syngenic recipients lacked for the number changes. The sera ELISA analysis revealed a strong production of vimentin IgG antibodies at 14 days ( 0. 230 ±0.018 vs. 0.063 ±0. 008,P <0. 05 ) in the allograft recipients, then slowly in-creased in later period. The assays did not detect IgG antibodies to vimentin in syngenic transplants at day 98. Conclusion: Cellular and humoral autoimmune responses against vimentin occurred in rat recipients undergoing chronic rejection. The novo autoimmne after transplantation appears to be involved in CAN.