Vasilescu Elena Rodica, Ho Eric K, Colovai Adriana I, Vlad George, Foca-Rodi Aurica, Markowitz Glen S, D'Agati Vivette, Hardy Mark A, Ratner Lloyd E, Suciu-Foca Nicole
Department of Pathology, Columbia University, New York, NY, USA.
Hum Immunol. 2006 Aug;67(8):597-604. doi: 10.1016/j.humimm.2006.04.012. Epub 2006 May 23.
The role of humoral immunity in causing antibody-mediated rejection (AMR) of organ allografts has been extensively documented. For this reason, negative complement-dependent cytotoxicity (CDC) cross-matches between recipient sera and donor T and B lymphocytes have become a mandatory requirement for cadaveric kidney transplantation. However, the significance of donor-specific antibodies (DSAs) detectable only by flow cytometry (FC) or solid phase assays (SPA) but not CDC is still controversial. We have performed a retrospective analysis of FC cross-matching results in 80 consecutive cadaver kidney allograft recipients. Antibodies against HLA class I and class II antigens were measured by CDC and SPA in sequential samples of sera obtained prior to transplantation. The preoperative cross-match was performed by CDC using magnetically sorted T and B cells from donor spleen. Sera obtained from each patient before and at the time of transplantation were included in the final cross-match. The sample of serum obtained at the time of transplantation was cross-matched retrospectively by FC and analyzed for anti-HLA antibody specificity on high resolution SPA. The actuarial kidney allograft survival at one year was 98%. Two of these eighty patients lost the graft, one due to AMR, the other for reasons unrelated to DSAs. Donor-specific antibodies were detected by FC in 17 of 80 patients, yet only 6 of 17 had an early episode of AMR. This episode was successfully reversed by desensitization therapy using intravenous immunoglobin (IVIG) and plasmapheresis. Flow cytomery cross-matching showed 95% specificity but only 35% sensitivity for prediction of AMR (p = 0.002). There was a significant correlation between high panel reactive antibodies (PRA) and positive FC cross-matching (p = 0 .0001), as well as high PRA and AMR (p = 0.0004 by CDC and 0.0011 by Luminex). Reversible AMR occurred 12-30 days post-transplantation in 8 patients. Of these 8 patients, 3 had no detectable DSAs in spite of C4d positivity, 4 had C4d deposition in conjunction with anti-HLA antibodies, and 1 patient had DSAs (anti-MICA) yet no C4d deposition. We conclude that early initiation of desensitization protocols can prevent transplant failure and that retrospective FC cross-matches may facilitate the diagnosis of AMR. Extensive analysis of patients' sera using a comprehensive set of tests may contribute to early treatment and better understanding of the mechanism underlying humoral rejection.
体液免疫在导致器官移植抗体介导的排斥反应（AMR）中的作用已得到广泛记载。因此，受体血清与供体T和B淋巴细胞之间的阴性补体依赖细胞毒性（CDC）交叉配型已成为尸体肾移植的一项强制性要求。然而，仅通过流式细胞术（FC）或固相分析（SPA）而非CDC检测到的供体特异性抗体（DSA）的意义仍存在争议。我们对80例连续的尸体肾移植受者的FC交叉配型结果进行了回顾性分析。在移植前采集的连续血清样本中，通过CDC和SPA检测针对HLAⅠ类和Ⅱ类抗原的抗体。术前交叉配型通过CDC使用从供体脾脏磁性分选的T和B细胞进行。将每位患者移植前和移植时获得的血清纳入最终交叉配型。移植时获得的血清样本通过FC进行回顾性交叉配型，并在高分辨率SPA上分析抗HLA抗体特异性。一年时尸体肾移植的精算生存率为98%。这80例患者中有2例移植肾丢失，1例因AMR，另1例与DSA无关。80例患者中有17例通过FC检测到供体特异性抗体，但17例中只有6例发生早期AMR。这一情况通过使用静脉注射免疫球蛋白（IVIG）和血浆置换的脱敏疗法成功逆转。流式细胞术交叉配型对AMR预测的特异性为95%，但敏感性仅为35%（p = 0.002）。高群体反应性抗体（PRA）与FC交叉配型阳性之间存在显著相关性（p = 0.0001），高PRA与AMR之间也存在显著相关性（CDC检测p = 0.0004，Luminex检测p = 0.0011）。8例患者在移植后12 - 30天发生可逆性AMR。在这8例患者中，3例尽管C4d阳性但未检测到DSA，4例C4d沉积并伴有抗HLA抗体，1例患者有DSA（抗MICA）但无C4d沉积。我们得出结论，脱敏方案的早期启动可以预防移植失败，回顾性FC交叉配型可能有助于AMR的诊断。使用一套全面的检测方法对患者血清进行广泛分析可能有助于早期治疗并更好地理解体液排斥反应的潜在机制。
