Li B, Hartono C, Ding R, Sharma V K, Ramaswamy R, Qian B, Serur D, Mouradian J, Schwartz J E, Suthanthiran M
Department of Medicine, Weill Medical College of Cornell University, New York, USA.
N Engl J Med. 2001 Mar 29;344(13):947-54. doi: 10.1056/NEJM200103293441301.
Acute rejection is a serious and frequent complication of renal transplantation, and its diagnosis is contingent on the invasive procedure of allograft biopsy. A noninvasive diagnostic test for rejection could improve the outcome of transplantation.
We obtained 24 urine specimens from 22 renal-allograft recipients with a biopsy-confirmed episode of acute rejection and 127 samples from 63 recipients without evidence of acute rejection. RNA was isolated from the urinary cells. Messenger RNA (mRNA) encoding the cytotoxic proteins perforin and granzyme B and a constitutively expressed cyclophilin B gene were measured with the use of a competitive, quantitative polymerase chain reaction, and the level of expression was correlated with allograft status.
The log-transformed mean (+/-SE) levels of perforin mRNA and granzyme B mRNA, which encode cytotoxic proteins, but not the levels of constitutively expressed cyclophiiin B mRNA, were higher in the urinary cells from the 22 patients with a biopsy-confirmed episode of acute rejection than in the 63 recipients without an episode of acute rejection (perforin, 1.4+/-0.3 vs. -0.6+/-0.2 fg per microgram of total RNA; P<0.001; and granzyme B, 1.2+/-0.3 vs. -0.9+/-0.2 fg per microgram of total RNA; P<0.001). Analysis involving the receiver-operating-characteristic curve demonstrated that acute rejection can be predicted with a sensitivity of 83 percent and a specificity of 83 percent with the use of a cutoff value of 0.9 fg of perforin mRNA per microgram of total RNA, and with a sensitivity of 79 percent and a specificity of 77 percent with the use of a cutoff value of 0.4 fg of granzyme B mRNA per microgram of total RNA. Sequential urine samples were obtained from 37 patients during the first nine days after transplantation; and measurements of the levels of mRNA that encoded cytotoxic proteins identified those in whom acute rejection developed.
Measurement of mRNA encoding cytotoxic proteins in urinary cells offers a noninvasive means of diagnosing acute rejection of renal allografts.
急性排斥反应是肾移植常见且严重的并发症，其诊断依赖于同种异体移植肾活检这一侵入性操作。一种用于诊断排斥反应的非侵入性检测方法可能会改善移植效果。
我们从22例经活检证实发生急性排斥反应的肾移植受者中获取了24份尿液标本，并从63例无急性排斥反应证据的受者中获取了127份样本。从尿细胞中提取RNA。使用竞争性定量聚合酶链反应检测编码细胞毒性蛋白穿孔素和颗粒酶B的信使核糖核酸（mRNA）以及组成性表达的亲环素B基因，并将表达水平与移植肾状态相关联。
在22例经活检证实发生急性排斥反应的患者的尿细胞中，编码细胞毒性蛋白的穿孔素mRNA和颗粒酶B mRNA的对数转换平均（±SE）水平较高，而组成性表达的亲环素B mRNA水平则不然。与63例未发生急性排斥反应的受者相比（穿孔素，每微克总RNA为1.4±0.3对-0.6±0.2 fg；P<0.001；颗粒酶B，每微克总RNA为1.2±0.3对-0.9±0.2 fg；P<0.001）。涉及受试者操作特征曲线的分析表明，使用每微克总RNA中穿孔素mRNA的截断值为0.9 fg时，预测急性排斥反应的敏感性为83%，特异性为83%；使用每微克总RNA中颗粒酶B mRNA的截断值为0.4 fg时，则敏感性为79%，特异性为77%。在移植后的前九天从37例患者中获取了连续的尿液样本；对编码细胞毒性蛋白的mRNA水平的测量确定了发生急性排斥反应的患者。
检测尿细胞中编码细胞毒性蛋白的mRNA为诊断肾移植急性排斥反应提供了一种非侵入性方法。
