Duquesnoy René J, Marrari Marilyn
Division of Transplant Pathology, Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA 15261, USA.
Arch Pathol Lab Med. 2003 Feb;127(2):149-56. doi: 10.5858/2003-127-149-MEOSAF.
This report presents results of the serum antibody analysis and crossmatch challenges in the proficiency testing program for histocompatibility testing jointly sponsored by the American Society for Histocompatibility and Immunogenetics and the College of American Pathologists.
To obtain information about consensus rates among participating laboratories that reported antibody screening and crossmatch results by direct complement-dependent lymphocytotoxicity (CDC) and/or anti-human globulin (AHG)-augmentation methods.
We analyzed responses from approximately 165 laboratories participating in 32 surveys during 1993-2000. Most of the testing was done by CDC methods, but increasing proportions of laboratories are using AHG augmentation of these techniques; almost one half of the serum screenings and crossmatches were done by AHG.
A total of 40 serum specimens were screened to determine the percent panel-reactive antibody (PRA) and identify HLA-specific antibodies. Participants often reported very wide ranges of PRA values. Panel-reactive antibody ranges exceeded 60 percentage points for 16 (40%) of the serum screening results by CDC and for 31 (77%) of the results by AHG. The interlaboratory variability of PRA values suggests that in many laboratories, the CDC or AHG procedures were often too insensitive or overly sensitive. The antibody identification results revealed inconsistent patterns among the participants performing CDC or AHG screening. Most participants reported the same primary antibody specificities by both methods. The consensus levels were generally high for the monospecific sera. On the other hand, there was much less agreement among the participants if the sera reacted with 2 or more HLA antigens. Participants using the more sensitive AHG method reported additional antibody specificities in many specimens, but invariably the consensus levels were rather low. A total of 192 serum-cell combinations were used for the crossmatch challenges. There was considerable interlaboratory variability; 21% of the CDC crossmatches and 36% of AHG crossmatches failed to reach the 90% consensus threshold.
This experience demonstrates considerable inconsistencies in serum screening and crossmatching among laboratories participating in the American Society for Histocompatibility and Immunogenetics/College of American Pathologists surveys. A lack of uniformity in test results may limit the efficient application of these methods in a clinical setting. Standardization of crossmatch and antibody screening techniques is highly desirable.
本报告展示了由美国组织相容性与免疫遗传学学会和美国病理学家学会联合主办的组织相容性检测能力验证计划中的血清抗体分析及交叉配型挑战结果。
获取有关参与实验室间通过直接补体依赖淋巴细胞毒性试验（CDC）和/或抗人球蛋白（AHG）增强法报告抗体筛查及交叉配型结果的一致率信息。
我们分析了1993年至2000年期间参与32次调查的约165个实验室的回复。大多数检测通过CDC方法进行，但使用AHG增强这些技术的实验室比例在增加；几乎一半的血清筛查和交叉配型是通过AHG完成的。
共筛查了40份血清标本以确定群体反应性抗体（PRA）百分比并鉴定HLA特异性抗体。参与者报告的PRA值范围通常非常宽泛。通过CDC进行的血清筛查结果中，有16份（40%）的PRA范围超过60个百分点，通过AHG进行的结果中有31份（77%）如此。PRA值的实验室间变异性表明，在许多实验室中，CDC或AHG程序往往要么过于不敏感要么过于敏感。抗体鉴定结果显示，进行CDC或AHG筛查的参与者之间模式不一致。大多数参与者通过两种方法报告的主要抗体特异性相同。单特异性血清的一致水平通常较高。另一方面，如果血清与2种或更多HLA抗原发生反应，参与者之间的一致性则低得多。使用更敏感的AHG方法的参与者在许多标本中报告了额外的抗体特异性，但一致水平始终相当低。共使用192种血清-细胞组合进行交叉配型挑战。存在相当大的实验室间变异性；21%的CDC交叉配型和36%的AHG交叉配型未达到90%的一致阈值。
这一经验表明，参与美国组织相容性与免疫遗传学学会/美国病理学家学会调查实验室的血清筛查和交叉配型存在相当大的不一致性。检测结果缺乏一致性可能会限制这些方法在临床环境中的有效应用。交叉配型和抗体筛查技术的标准化非常必要。
