PCR-STR用于异基因造血干细胞移植后的骨髓和外周血嵌合状态的监测及作用

Difference between the bone marrow and peripheral blood engraftment evidence after allogeneic hematopoietic stem cell transplantation by PCR-STR

目的用PCR-STR检测观察比较异基因造血干细胞移植术后,骨髓和外周血嵌合状态和植入状态。方法提取17例异基因造血干细胞移植术中的供者外周血及受者移植前后各阶段外周血和骨髓的DNA,PCR PCR-STR检测扩增15个基因位点,和1个性别位点AMEL。用遗传分析仪进行毛细管电泳,确定基因位点,根据基因型的差异选择嵌合率计算公式,分析植入情况和嵌合状态。结果12名患者完全植入,骨髓和外周血的PCR-STR结果一致;1名患者骨髓PCR-STR显示为持续未植入,外周血PCR-STR显示为短期混合植入;4名患者骨髓和外周血PCR-STR显示嵌合状态时间不一致,骨髓PCR-STR显示嵌合状态时间明显早于外周血(P<0.05)。结论PCR-STR是分析异基因造血干细胞移植后供体是否植入的灵敏、准确度高的方法,骨髓嵌合状态的变化的出现早于外周血,混合嵌合状态对白血病复发有预警作用,骨髓嵌合状态的早期变化对实施临床干预治疗尤为重要。

Objective To observe the difference between the bone marrow and peripheral blood engraftment evidence after ailogeneie haemopoietie stem cell transplantation （ Allo-HSCT ） using PCR-STR. Methods DNA from peripheral blood or bone marrow of donors and recipients in different phases were extracted, and 16 STR loci with high polymorphism were amplified by PCR. Separation of the PCR products and fluorescence detection were performed by ABIprism 3100 Genetic Analyzer with capillary eleetrophoresis. Results The 16 patients included in the study had different levels of engraftment. Twelve patients displayed complete ehimerism, while 5 patients showed mixed chimerism. One patient was keeping continuance of remission. The decrease of donor DNA amounts in mixed chimerism was earlier in bone marrow than that in peripheral blood（ P 〈 0.05 ）. Conclusion PCR-STR is sensitive and accurate in analyzing the chimera status after Allo- HSCT. Mixed ehimerism in bone marrow is earlier than that in peripheral blood. It has a predictive role for leukemia relapse and chimera status could guide the treatment.