Suttorp M, Schmitz N, Dreger P, Schaub J, Löffler H
Second Department of Internal Medicine, University of Kiel, Germany.
Leukemia. 1993 May;7(5):679-87.
Highly polymorphic tandemly repetitive DNA sequences provide powerful genetic markers for the identification of individuals by restriction fragment length polymorphisms (RFLP) even in close relatives. Over a three-year period, 61 consecutive patients from a single institution undergoing allogeneic bone marrow transplantation (BMT) for various hematological diseases were grafted with unmanipulated marrow and followed for the development of hematopoietic chimerism. Three synthetic oligonucleotide probes homologous to the so-called minisatellite or variable number of tandem repeat (VNTR) sequences were evaluated in the clinical setting of BMT for their usefulness: (i) to document marrow engraftment or rejection; (ii) to elucidate the kinetics of mixed chimerism; and (iii) in providing a sensitive tool for early detection of relapse. In addition, in patients with CML karyotyping and analysis of bcr/abl gene rearrangement was performed. Using this panel of three oligonucleotide probes, informative markers specific for donor or recipient RFLP could be demonstrated in all cases. Engraftment could be documented in all patients surviving beyond day +14 after BMT. Mixed chimerism was detected in 14% of the patients in the early phase (day +14 to day +78) after BMT but only one patient turned out to become a long-term stable mixed chimera. These results support the hypothesis that lymphocytes of recipient origin surviving the conditioning regimen may considerably contribute to mixed chimerism early after BMT. Long-term stable mixed chimerism is a rare event after BMT with unmanipulated marrow. Simultaneous analysis of chimerism after BMT by VNTR-RFLP, karyotyping, and detection of bcr/abl rearrangement in patients with CML showed corresponding results in nine out of 12 patients. In three patients either one of the methods failed to detect residual recipient cells in the early phase after BMT. Therefore different methods for assessment of mixed chimerism seem to complement rather than to exclude each other. Eleven patients who all exhibited complete chimerism early after BMT relapsed from their underlying disease. In seven of these patients grafted for acute leukemia, analysis of DNA-RFLP had been performed shortly before clinical relapse (30-86 days) and failed to herald relapse. As the sensitivity for the detection of the minor cell population by analysis of DNA-RFLPs is approximately 1%, these data may indicate that relapse of acute leukemia after BMT is characterized by a sudden increase in the percentage of recipient blast cells not detectable even by frequent RFLP analyses.
高度多态的串联重复DNA序列提供了强大的遗传标记，可通过限制性片段长度多态性（RFLP）来识别个体，即使是近亲也适用。在三年时间里，来自同一机构的61例连续患者因各种血液系统疾病接受了异基因骨髓移植（BMT），移植的是未处理的骨髓，并对造血嵌合体的发展进行了随访。在BMT的临床环境中评估了三种与所谓的小卫星或可变串联重复序列（VNTR）同源的合成寡核苷酸探针的用途：（i）记录骨髓植入或排斥；（ii）阐明混合嵌合体的动力学；（iii）提供早期检测复发的敏感工具。此外，对慢性粒细胞白血病（CML）患者进行了核型分析和bcr/abl基因重排检测。使用这三种寡核苷酸探针组成的检测组，在所有病例中都能证明供体或受体RFLP的信息性标记。在BMT后存活超过+14天的所有患者中都记录到了植入情况。在BMT后的早期阶段（+14天至+78天），14%的患者检测到混合嵌合体，但只有一名患者成为长期稳定的混合嵌合体。这些结果支持这样的假设，即经过预处理方案后存活的受体来源淋巴细胞可能在BMT后早期对混合嵌合体有显著贡献。在接受未处理骨髓的BMT后，长期稳定的混合嵌合体是一种罕见事件。对BMT后的嵌合体进行VNTR-RFLP、核型分析以及对CML患者检测bcr/abl重排的同步分析显示，12例患者中有9例结果一致。在3例患者中，BMT后早期有1种方法未能检测到残留的受体细胞。因此，评估混合嵌合体的不同方法似乎是互补的，而不是相互排斥的。11例在BMT后早期均表现为完全嵌合体的患者，其基础疾病复发。在这些因急性白血病接受移植的患者中，有7例在临床复发前（30 - 86天）不久进行了DNA-RFLP分析，但未能预测复发。由于通过DNA-RFLP分析检测微小细胞群体的敏感性约为1%，这些数据可能表明BMT后急性白血病的复发特征是受体原始细胞百分比突然增加，即使频繁进行RFLP分析也无法检测到。
