Corti B, Altimari A, Gabusi E, Pinna A D, Lauro A, Morselli-Labate A M, Gruppioni E, Pirini M G, Fiorentino M, Ridolfi L, Grigioni W F, D'Errico-Grigioni A
Department of Oncology and Hematology, University of Bologna, Bologna, Italy.
Transplant Proc. 2005 Dec;37(10):4467-71. doi: 10.1016/j.transproceed.2005.11.035.
Granzyme B (GrB) and perforin are promising markers to predict acute rejection episodes of transplanted organs. Having recently reported that immunohistochemical expression of GrB/perforin correlates with histologically assessed acute cellular rejection (ACR) episodes in intestinal transplantation recipients, herein we have additionally explored the potential of real-time polymerase chain reaction (PCR) assessment of GrB/perforin gene up-regulation in peripheral blood mononuclear cells. Both immunohistochemical evaluation of GrB/perforin expression and real-time PCR assessment of up-regulation, which was defined as a 2-fold increase with respect to "basal" levels during maintenance immunosuppressive protocols, were performed among a population of 23 intestinal transplant recipients under routine surveillance, in addition to histological analysis of ACR. The ACR scores showed direct relationships both with GrB/perforin immunohistochemistry (IHC) scores (P < .001) and with gene up-regulation by real-time PCR (P = .004). Furthermore, real-time PCR upregulation was associated with the IHC score (P < .001). A preliminary analysis of diagnostic accuracy-performed to gain information to plan future studies-indicated that when using histological assessment as the reference technique, our current definition of PCR up-regulation provided good specificity (84%) but insufficient sensitivity (44%) for a noninvasive prediction of ACR. The results of this pilot study suggested that real-time PCR analysis of GrB/perforin upregulation may help therapeutic decision making, and have the potential for detection of presymptomatic rejection. More extensive studies must investigate strategies to improve the sensitivity of the analyses of GrB/perforin up-regulation.
颗粒酶B（GrB）和穿孔素是预测移植器官急性排斥反应发作的有前景的标志物。最近有报道称，GrB/穿孔素的免疫组化表达与肠道移植受者经组织学评估的急性细胞排斥反应（ACR）发作相关，在此我们还探讨了通过实时聚合酶链反应（PCR）评估外周血单个核细胞中GrB/穿孔素基因上调的潜力。除了对ACR进行组织学分析外，还在23名接受常规监测的肠道移植受者中进行了GrB/穿孔素表达的免疫组化评估以及上调的实时PCR评估，上调定义为维持免疫抑制方案期间相对于“基础”水平增加2倍。ACR评分与GrB/穿孔素免疫组化（IHC）评分（P <.001）和实时PCR基因上调均呈直接关系（P =.004）。此外，实时PCR上调与IHC评分相关（P <.001）。为获取信息以规划未来研究而进行的诊断准确性初步分析表明，当使用组织学评估作为参考技术时，我们目前对PCR上调的定义对于ACR的无创预测具有良好的特异性（84%）但敏感性不足（44%）。这项初步研究的结果表明，对GrB/穿孔素上调进行实时PCR分析可能有助于治疗决策，并具有检测症状前排斥反应的潜力。更广泛的研究必须调查提高GrB/穿孔素上调分析敏感性的策略。
