Transplant immuno-diagnostics: crossmatch and antigen detection.

Identifying and monitoring donor-directed anti-human leukocyte antigen antibodies are a rapidly evolving area of solid organ transplantation. Donor-specific antibodies dictate pre-transplant donor choice and donor-recipient matching and underlie much acute and chronic allograft rejection and loss. The evolution of available technology has driven this progress. Early, labor intensive, whole-cell assays based on complement-dependent cytotoxicity suffered from poor sensitivity and specificity, technical challenges and lack of precision. Sequential improvement in assay performance included antihuman immunoglobulin-enhanced complement-dependent cytotoxicity techniques followed by cell-based flow cytometry. However, variable specificity and sensitivity inherent in cell-based testing continued to limit flow cytometry. The introduction of solid-phase assays led to a second revolution in histocompatibility testing with the use of purified antigens bound to artificial surfaces rather than whole cells. These techniques augmented sensitivity and specificity to detect even low-titer antibodies to previously undetected antigens. Identification of complement-activating antibodies is being introduced but current technology is in the developmental stage. While detection of alloantibodies has improved dramatically, our comprehension of their importance remains imperfect. Variability in methodology and a lack of standardization limits the clinical application of these tests. In spite of the hurdles that remain, antibody-mediated rejection has become a key target to improve graft survival.

识别和监测供体特异性抗人白细胞抗原抗体是实体器官移植中一个快速发展的领域。供体特异性抗体决定移植前供体的选择以及供体 - 受体的匹配，并是许多急性和慢性同种异体移植物排斥和丢失的基础。现有技术的发展推动了这一进步。早期基于补体依赖细胞毒性的劳动密集型全细胞检测方法存在敏感性和特异性差、技术难题以及缺乏精确性等问题。检测性能的逐步提高包括抗人免疫球蛋白增强的补体依赖细胞毒性技术，随后是基于细胞的流式细胞术。然而，基于细胞的检测所固有的可变的特异性和敏感性继续限制了流式细胞术的应用。固相检测的引入引发了组织相容性检测的第二次革命，它使用结合在人工表面而非全细胞上的纯化抗原。这些技术提高了检测针对以前未检测到的抗原的低滴度抗体的敏感性和特异性。补体激活抗体的识别正在被引入，但目前的技术还处于发展阶段。虽然同种抗体的检测有了显著改善，但我们对其重要性的理解仍然不完善。方法的差异性和缺乏标准化限制了这些检测的临床应用。尽管仍然存在障碍，但抗体介导的排斥已成为提高移植物存活率的关键目标。