筑巢式PCR等多项指标对小儿急性白血病微量残留病的监测

DYNAMIC DETECTION OF MINIMAL RESIDUAL DISEASE IN CHILDREN WITH ACUTE LEUKEMIA BY NEST PCR AND OTHER DETECTING INDICES

①目的 探讨采用筑巢式聚合酶链反应（Ｎｅｓｔ－ＰＣＲ）等多项指标监测小儿急性白血病（ＡＬ）微量残留病（ＭＲＤ）的临床意义。②方法 对１５２ 例ＡＬ在形态学、免疫学和细胞遗传学（ＭＩＣ）分型诊断的基础上，结合Ｎｅｓｔ－ＰＣＲ，姐妹染色单体交换（ＳＣＥ）、染色体核型分析方法进行ＭＲＤ监测。③结果 对５８ 例急性淋巴细胞白血病（ＡＬＬ）进行了Ｔ细胞受体（ＴＣＲ）Ｖδ２Ｄδ３ 基因重排监测，其中８３％ 的Ｂ－ＡＬＬ和２５％ 的Ｔ－ＡＬＬ具有此基因重排，检测灵敏度为１０－ ５～１０－ ６ ．对４４ 例ＡＬＬ进行了ＭＲＤ动态监测，结果显示化疗期间ＰＣＲ由阴性转为阳性或持续阳性者，易引起骨髓复发、死亡。ＰＣＲ转阴时间有明显个体差异性。持续完全缓解３ 年以上的ＡＬＬ病儿ＰＣＲ持续阴性可作为停药治疗的可靠指标。对７６ 例ＡＬ进行了ＳＣＥ动态监测，结果表明ＳＣＥ频率变化与疾病的严重程度呈平行关系。对６１ 例ＡＬ进行了染色体核型动态监测，结果表明初发ＡＬ染色体核型正常者亦有ＤＮＡ 严重损伤。④结论 在ＭＩＣ分型诊断的基础上，采用Ｎｅｓｔ－ＰＣＲ，ＳＣＥ，染色体核型分析等多项指标进行ＡＬ的ＭＲＤ动态监测、综合分析评价，对指导治疗。

Objective\ To explore the clinical significance of detecting minimal residual disease (MRD) in children with acute leukemia (AL) by using the methods of nest polymerize chain reaction (Nest PCR) and other detecting indexes.\ Methods Based on the morphological, immunological and cytogenetic (MIC) classification, Nest Polymerize chain reaction (Nest PCR), the frequency of the sister chromatic exchange (SCE) and the chromosome karyotype analysis were used to detect MRD in 152 children with AL.\ Results\ Among the 58 cases with ALL, the positive rates of T cell receptor (TCR) Vδ2 Dδ3 gene rearrangement were 83% in B ALL and 25% in T ALL. The detecting sensitivities of MRD was 10 -5 -10 -6 . The MRD in 44 of 58 patients with ALL was dynamically detected and the result showed that when PCR was converted into positive from negative or persistent positive, death was possible because of the bone marrow relapse. The time of PCR from negative to positive had obviously individual difference. It should be as an index of terminating chemotherapy that the MRD PCR was persistent negative in ALL children over 3 years of the continuous and complete remission. The frequency of SCE of bone marrow cell was dynamically detected in 76 cases with AL and the result showed that there was a parallel relation between the frequency of SCE and the serious degree of the disease. The chromosome karyotype was dynamically analyzed in 61 cases with AL and the result showed that DNA in the initial AL cases with normal chromosome karyotype was also severely damaged.\ Conclusion\ Based on the typing and diagnosis of MIC, by using PCR,SCE and chromosome karyotype analysis, dynamically detecting, analysing and evaluating generally MRD in AL children is of clinical significance in guiding treatment, predicting bone marrow relapse and evaluating prognosis. \;