肾移植急性排斥反应时尿中供体细胞DNA检测的临床意义

目的通过对肾移植患者急性排斥反应时尿中出现的供体细胞的DNA进行检测,试图找到一种方便快速、无创性诊断肾移植急性排斥反应的新方法.方法以供体为男性,受体为女性或HLA-DR抗原有错配的肾移植患者80例为研究对象,其中急性排斥反应34例,肾功能正常者41例,药物性肾功能损伤5例.利用PCR及PCR-SSP法分别检测Y染色体上特异的基因片断SRY、DYZ-1和HLA-DR抗原的基因片断DRBl.结果供体为男性的女性急性排斥反应患者11例,SRY阳性10例(90.9%),DYZ-1阳性11例(100%);对照组肾功能正常患者14例,SRY的检测结果为阳性1例,阴性13例(92.8%);DYZ-1阳性2例,阴性12例(85.7%).HLA-DR抗原有错配的急性排斥反应23例,DRBl阳性21例(91.3%),阴性2例,经抗排斥治疗17例转为阴性;对照组肾功能正常患者27例,DRBI阳性3例,阴性24例(88.9%).药物性肾功能损伤5例的PCR检测结果均为阴性.结论肾移植术后急性排斥反应发生时,患者尿中来自供体细胞的DNA高频率地出现,随着抗排斥治疗移植肾功能恢复而消失.同时,肾功能正常及药物性肾功能损伤患者供体细胞的DNA检测为阴性,说明肾移植患者尿中供体细胞DNA的PCR检测可以作为诊断急性排斥反应并与药物性肾功能损伤进行鉴别的一种崭新方法.

PCR and PCR-SSP for detection of urinary donor-origin DNA in renal transplant recipient with acute rejection

Objective: The purpose of this study was to establish a method for accurate diagnosis of acute re jection by donor spccific DNA analysis of urine. Methods: DNAs of 34 patients with episode of acute rejection and 5patients with drug - induced renal dysfunctions were examined. 41 patients without any trouble after renal transplantation were acted as the controll. DNA extracted from urines was performed with PCRs to examine Y - chromosome (SRY and DYZ - 1 ) in female patients and HLA - DR mismatched grafts. Results: Female recipients from male donors: SRY and DYZ - 1 on Y - chronosome of urine were positive in 1 of 14 patients with stable renal functions. On the other hand, SRY and DYZ - 1 were all positive in 4 patients with acute rejection, in which 1 became negative and 3 remained positive 3 ～6 months after discharge. Recipients from HLA mismatched donors: DRB1 was positive in 3of 27 patients with stable renal functions. At the same time, it was positive in 21 of 23 patients with acute rejection,in which 17 became negative and 2 remained positive at the time of discharge. Conclusion: The appearance of donor DNA in urine is strongly associated with acute rejection. Therefore, analysis of urinary DNA from donor origin was effective and accurate for diagnosis of acute rejection in the renal transplantation.