肾移植慢性移植物失功中肾实质细胞的凋亡

背景:移植物内细胞毒性T细胞对肾小管上皮细胞的浸润,造成上皮细胞的凋亡、肾脏组织的破坏是引起肾移植排斥反应的重要原因.目的:探讨临床肾移植后慢性移植物失功期移植肾实质细胞凋亡与移植肾慢性失功的关系.设计、时间及地点:病例对比观察,于2005-01/2008-01在中山大学附属第一医院完成.对象:选择2004/2006中山大学附属第一医院器官移植科肾移植专科行移植肾穿刺活检术患者30例,按活检原因分成实验组(n=20)及对照组(n=10).实验组患者出院时血肌酐降到正常,尿蛋白定性检测阴性,但在术后1～3年随访期间出现尿蛋白定性逐渐+～+++,血肌酐检测逐渐爬行升高;对照组患者活体肾移植前零点活检.方法:实验组行24 h尿蛋白定量检测,B超引导下移植肾穿刺活检术,标本1份以常规病理染色和Masson's特殊染色行Banff 97病理分类诊断,1份做优化的切片温度包埋冰冻切片,采用末端脱氧核苷酸转移酶介导的脱氧核苷酸原位末端标记法检测肾实质细胞凋亡.对照组活检标本也行同样病理检查.主要观察指标:显微镜下计数10个高倍镜下肾实质细胞平均凋亡个数,计算凋亡指数.实验组检测活检时患者血肌酐值及24 h尿蛋白定量.结果:实验组1例因穿刺组织过少,未出病理报告,2例肾移植后急性排斥,4例Ig A肾病复发,13例符合肾移植后慢性移植物肾病病理改变,其中2例肾功能丢失.对照组均为基本正常肾组织.入组时实验组肾实质细胞凋亡个数明显高于对照组(P＜0.01),特别是在血肌酐和尿蛋白定量均较高的患者中.实验组细胞凋亡指数同入组时血肌酐爬升程度呈直线相关(r=0.733,P＜0.01),并且与患者24h尿蛋白严重程度基本一致.结论:肾实质细胞凋亡在慢性移植肾失功发生演变过程中发挥了重要作用.

Renal parenchymal cells apoptosis in chronic graft dysfunction following kidney transplantation

BACKGROUND:The renal graft rejection is mainly caused by cytotoxic T lymphocyte infiltrate renal tubular epithelial cells,which lead to the epithelial cells apoptosis and disorganization of renal tissues.OBJECTIVE:To elucidate the relationship between renal parenchymal cells apoptosis and chronic graft dysfunction(CGD)following renal-transplantation.DESIGN,TIME AND SETTING:A Case-controlled study was performed at the First Affiliated Hospital of Sun Yat-sen University from January 2005 to January 2008.PARTICIPANTS:Thirty cases underwent renal needle biopsy at the Department of Organ Transplantation,the First Affiliated Hospital of Sun Yat-sen University from 2004 to 2006 were divided into experimental(n=20)and control(n=10)groups.In the experimental group,cases with normal serum creatinine(Scr)post-renal-transplantation and urine protein(-)when discharged, however,the Scr creeping increased and urine protein(+-+++)when 1-3 years post-operation.The control group consists of samples from zero-hour biopsy of living-related donor kidney.METHODS:In the experimental group,24 h quantitive urine protein was examined,and all graft samples were subjected to histological examination.Haematoxylin-eosin and Masson's staining and Banff97 diagnosis were performed.Parenchymatous tissue cells apoptosis were monitored by Terminal-deoxynucleotidyl transferase mediated DIG-Dutp nick-end labeling(TUNEL).The same examination was performed in the control group.MAIN OUTCOME MEASURES:Apoptotic index was calculated by counting mean apoptosis numbers of parenchyma cells via microscope with 10 high power lens fields.In addition,the Scr value and 24 h quantitive urine protein was detected.RESULTS:One case without pathological diagnosis report duo to biopsy tissues is too small,2 cases occurred acute rejection,4 cases recurrence of Ig A nephropathy,13 cases consistent with pathological changes of chronic allograft nephropathy and 2 of them lost function of allograft.The TUNEL showed that the number of apoptosis cells in experimental group was significantly higher than that in the control group(P＜0.01),especially in the patients with higher quantitive urine protein and Scr.The appoptotic index of the experimental group was linear correlated to the level of Scr(r=0.733,P＜0.01),which was basically identical to 24 h quantitive urine protein.CONCLUSION:Apoptosis of renal parenchymal cells may play an important role in CGD of renal transplantation.