儿童急性淋巴细胞白血病特异性标记物的精准检测方法研究

目的：T细胞和免疫球蛋白重链基因重排是微小残留病灶水平的特异性标记物，而微小残留病灶的水平与儿童急性淋巴细胞白血病的复发强烈相关。应用传统的聚合酶链式反应方法来监测IgH／TCR基因重排不仅耗时、耗人力，而且敏感度较低。本研究旨在探索一种更为高效和敏感与实用的监测IgH／TCR基因重排的精准检测方法。方法：应用多重PCR技术检测26个患有急性淋巴细胞白血病的儿童的外周血样品中的标记物，这些儿童是在中国哈尔滨市最近两年内被诊断的患者。分别应用基因扫描和毛细血管电泳方法检测IgH（FRI，FRII，FRⅢ）／TCR（TCRB，TCRγ）基因重排和分析PCR产物的片段。结果：IgH／TCR基因重排和对IgH基因重排的阳性率分别为92．3％和75％，在26个病例中，4个复发病人的IgH的三个片段（FRI，FRII，FRⅢ）基因重排显示阳性。进一步分析显示复发与ign基因重排呈线性相关。结论：实验与临床应用表明，基因扫描这种方法对于IgH／TCR基因重排的检测是可靠的、实用的，因而可用于儿童急性淋巴细胞白血病的诊断和随访。

Study on the Sensitive Method for Screening the Markers of Children Acute Lymphatic Leukemia

Objective： T-cell receptor （TCR） and immunoglobulin heavy chain （IgH） gene rearrangements are specific markers of minimal residual disease levels that are strongly correlated with the risk of relapse of childhood acute lymphoblastic leukemia （ALL）. However, conventional polymerase chain reaction （PCR） methods to detect IgI-I/TCR gene rearrangements are time-consuming, labor-in- tensive and less sensitive. To explore a more efficient and sensitive method. Methods： We used multiplex PCR to detect these markers in peripheral blood samples of 26 children with ALL diagnosed in 2 years in Harbin, China. We used Gene Scan method in detection oflgH （FRI, FRII and FRIII）/TCR （TCR β and TCR γ） gene rearrangements and performed fragment analysis of PCR products by capillary elec- trophoresis. Results： The result showed that positive rate for IgHfrCR gene rearrangements and for IgH gene rearrangements was 92.3% and 75%, respectively. Among the 26 cases, four patients who suffered from relapsing showed positive gene rearrangements of all the three fragments of IgH （FRI, FRII and FRIII）. Further analysis revealed a linear correlation between relapsing and IgH gene rearrange- ments. Conclusion： Our experiment and clinical applications indicate that Gene Scan method is reliable and applicable for detection of IgH/TCR gene rearrangements. Thus, our method can be used in diagnosis and follow-up in Childhood ALL.