吲哚胺2，3双加氧酶在诊断肝移植急性排斥中的作用

Role of indoleamine 2, 3-dioxygenase in diagnosing rat＇ s acute rejection after liver transplantation

目的探讨外周血吲哚胺2，3双加氧酶（IDO）基因表达对大鼠肝移植急性排斥反应（AR）的诊断价值。方法建立大鼠原位肝移植模型，分为4组：A组：同基因移植组（Wistar—Wistar，n=32）；B组：异基因移植组（SD—Wistar，n=32）；C组：异基因移植＋长期环孢素A组（CsA，n=32）；D组：异基因移植＋短期CsA组（用药剂量同C组，第3天起停药，n=32）。应用实时聚合酶链反应（Real—timePCR）方法分别检测术后第0、1、2、3、4、5、7、9天外周mIDO mRNA值，同时检测各时间点血清谷草转氨酶（AST）、总胆红素（T—BIL）、碱性磷酸酶（ALP）水平，并取肝脏病理切片。结果A组外周血IDO mRNA呈持续低水平，AST、T—BIL、ALP逐渐降至正常，病理无排斥反应。C组检测结果与A组相似。B组IDO mRNA显著上升为术后第2天（P〈0．05），AST、T—BIL、ALP值显著上升为术后4d（P〈0．01），病理切片判断轻度排斥为术后5d（χ^2=4．8，P〈0．05）。D组IDOmRNA显著上升为术后第4天（P〈0．05），AST、T—BIL、ALP值显著上升为术后5d（P〈0．01），病理切片判断轻度排斥为术后7d（χ^2=4．8，P〈0．05）。结论外周血IDO mRNA检测可较病理检查更早诊断大鼠肝移植AR的发生，且方法简单、安全。

Objective To study the diagnostic value of indoleamine 2, 3-dioxygenase （IDO） gene expression in acute liver rejection in rat orthotopic liver transplantation model. Methods The rat orthotopic liver transplantation models were divided into four groups： group A, isograft transplantation group （Wistar to Wistar） ; group B, allograft transplantation （SD to Wistar） ; group C, allograft transplantation and cyclosporine; Group D, allograft transplantation and cyclosporine （the drug was withdrawn on the 3rd day after the operation）. The samples （peripheral blood and liver tissue） were obtained on the operation day, 1st, 2rid, 3rd, 4th, 5th, 7th and 9th day post-operation. Luorescent quantitative polymerase chain reaction （PCR） , pathological study and serum test were performed on each sample. Results In groups A and C, the IDO mRNA was expressed at a low level, aspartate aminotransferase （AST）, total bilirubin （T-BIL） and alkaline phosphatase （ALP） were decreased to the normal level, and the pathological test found no acute rejection （AR）. In group B, the IDO mRNA was dramatically increased on the day 2 （ P 〈 0. 05 ）, AST, T-BIL and ALP rose dramatically on the day 4 （P 〈 0. 05） , and mild AR was detected on the day 5 （χ^2 = 4. 8,P 〈 0. 05 ）. In group D, the IDO mRNA was dramatically increased on the day 4 （ P 〈 0. 05 ） , AST, T-BIL and ALP rose dramatically on the day 5 （ P 〈 0. 01 ）, and mild AR was detected on the day 7 （χ^2 = 4.8, P 〈 0. 05 ）. Conclusion Comparing with pathological study, detecting IDO mRNA of peripheral blood can diagnose AR of rat at earlier stage and the technique is safe and simple.