血清的EDTA治疗降低了T细胞和B细胞在流细胞计交叉匹配中的假阳性:一个多中心研究
Marzanna Krolik1, Prasad Phirke2, Eun-Sang Oh1
1HLA Laboratory, Department of Pathology, Westchester Medical Center, Valhalla, New York, USA.
HLA
|September 21, 2025
概括
血清样本的乙烯基二胺三酸 (EDTA) 处理有效地减少了流式细胞计交叉匹配 (FCXM) 的假阳性结果. 这种简单的方法通过提高FCXM的准确性来增强移植决策,特别是在B细胞非酶处理试验中.
科学领域:
- 移植免疫学 移植免疫学
- 临床诊断 临床诊断 临床诊断
- 免疫抑制的监测监测.
背景情况:
- 在T或B细胞流细胞计交叉匹配 (FCXM) 中假阳性结果使移植决策复杂化.
- 提高FCXM的准确性对于成功的器官移植结果至关重要.
研究的目的:
- 调查乙烯基二胺三酸 (EDTA) 治疗在减少FCXM错误阳性反应中的有效性.
- 评估EDTA治疗对FCXM敏感性和特异性的影响.
主要方法:
- 这是一项涉及两个独立实验室的多中心研究.
- 血清样本用EDTA处理,并与未处理和其他处理样本 (pronase,2-mercaptoethanol,Dithiothreitol,热不活化) 相比较.
- 评估的B细胞非酶治疗 (NP) FCXM和T细胞酶治疗 (PT) FCXM.
主要成果:
- 治疗EDTA有效地消除了B细胞NP FCXM的虚假阳性,可能是通过减少聚合IgG.
- 用EDTA治疗的血清显示出与B细胞前酶治疗 (PT) 的FCXM (灵敏度94%,特异性96%) 相似的疗效.
- 用EDTA处理的血清表现优于T细胞PT FCXM,并且优于B细胞NP FCXM的Dithiothreitol或热失活.
结论:
- 治疗EDTA是一种简单,有效的方法,通过减少假阳性来提高FCXM质量.
- EDTA治疗可以集成到NP和PT FCXM协议中.
- 在B细胞NP FCXM中采用EDTA处理的血清可以减少B细胞PT FCXM的必要性,简化移植前评估.
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