Chowdhry Mohit, Makroo Raj Nath, Kakkar Brinda, Thakur Yogita, Kumar Manoj, Singh Mandhata
Department of Transfusion Medicine and Immunology, Indraprastha Apollo Hospitals, New Delhi, India.
Department of Transfusion Medicine, Institute of Liver and Biliary Sciences, New Delhi, India.
Asian J Transfus Sci. 2018 Jul-Dec;12(2):160-164. doi: 10.4103/ajts.AJTS_95_17.
Transplant recipients are always at a risk of developing anti-human leukocyte antigen (HLA) antibodies due to prior sensitizing events such as blood transfusions, multiple pregnancies, or transplantation. Unexpected positive outcomes can be seen in complement dependent cytotoxicity (CDC) based assays due to underlying autoimmune disorders or pharmacological treatment (rituximab/intravenous immunoglobulin/anti-thymocyte globulin administration), therefore, limiting its value. CDC based assay results strongly depend on the vitality of the donor lymphocytes, highlighting another major limitation of this assay. Thus, as an alternative approach, solid phase based crossmatch assays were introduced which function independently of the cell quality and have higher sensitivity and specificity in detecting anti-HLA antibodies. We describe a case where the patient awaiting renal transplantation from living related donor was evaluated by pretransplant histocompatibility testing for the detection of anti-HLA antibodies. The histocompatibility testing revealed positive CDC anti-human globulin and flow crossmatch along with negative Luminex based assays (HLA antibody screen, luminex crossmatch, and luminex single bead assay). Detailed histocompatibility workup revealed immunoglobulin G autoantibodies which were complement activating and lympocytoxic in nature.
由于先前的致敏事件，如输血、多次妊娠或移植，移植受者始终有产生抗人白细胞抗原（HLA）抗体的风险。由于潜在的自身免疫性疾病或药物治疗（利妥昔单抗/静脉注射免疫球蛋白/抗胸腺细胞球蛋白给药），在基于补体依赖细胞毒性（CDC）的检测中可能会出现意外的阳性结果，因此限制了其价值。基于CDC的检测结果强烈依赖于供体淋巴细胞的活力，这突出了该检测的另一个主要局限性。因此，作为一种替代方法，引入了基于固相的交叉配型检测，其功能独立于细胞质量，并且在检测抗HLA抗体方面具有更高的灵敏度和特异性。我们描述了一个案例，一名等待活体亲属供肾移植的患者通过移植前组织相容性检测来检测抗HLA抗体。组织相容性检测显示CDC抗人球蛋白和流式交叉配型呈阳性，而基于Luminex的检测（HLA抗体筛查、Luminex交叉配型和Luminex单珠检测）呈阴性。详细的组织相容性检查发现了免疫球蛋白G自身抗体，其具有补体激活和淋巴细胞毒性。
