儿童急性白血病T细胞受体δ、γ基因重排连接区序列的动态分析

目的 探讨儿童急性淋巴细胞白血病（ＡＬＬ）患在初诊、完全缓解（ＣＲ）及复发不同时期的Ｔ细胞３受体（ＴＣＲ）δＶ－Ｄ，γＶ－Ｊ基因重排连接区序列的差异及其意义。方法 采用Ｔ－载体分子克隆测离１限制性酶团及聚合酶链反应等技术，对３４丛ＡＬＬ患标本进行ＴＣＴδ、γ连接区序列动态分析。结果 ３４丛ＡＬＬ患标本进行ＴＣＲ－５γ连接区序列动态分析。结果 ３４份ＡＬＬ患标本的ＴＣＲ５、γ基因重排序列在初

Dynamic analysis of junctional sequences of T cell receptor (TCR) delta and gamma gene rearrangement in childhood with acute lymphoblastic leukemia]

OBJECTIVE: To explore the junctional sequence difference of T cell receptor delta and gamma gene rearrangement in childhood acute lymphoblastic leukemia (ALL) at diagnosis, complete remission (CR) and relapse. METHODS: By using the T-vector molecular cloning and sequencing and polymerase chain reaction, the junctional sequences of TCRdeltaV-D and TCRgammaV-J were dynamically analyzed in 34 bone marrow samples of ALL. RESULTS: The junctional sequence of TCR delta, gamma gene showed significant difference and regularity before and after remission and during relapsed periods. The sequence of TCRdeltaV-D were analyzed in 24 samples from ALL. Among them, the intact Vdelta2 and 5'Ddelta3 sequences were observed in 10 samples at diagnosis, of which 7 samples had T-->C mutation in Ddelta3 nonamer sequence. The deletions of rearranged Vdelta2, 5'Ddelta3 and Ddelta3 haptamer sequences were found in 11 complete remission (CR) samples with ALL, but none had T-->C mutation in Ddelta3 nonamer sequence. The deletion rate of Vdelta2 or Ddelta3 sequences and the T-->C mutation in Ddelta3 nonamer sequence were extremely differed between samples at diagnosis and in remission (calculate exact probabilities P = 0.001). The junctional rearrangement sequence of 5'Ddelta3 sequences tended to remain intact in 3 relapsed samples. The findings of TCRgammaV-J sequences were similar to that of TCRdeltaV-D in 10 ALL patients. CONCLUSION: The difference of TCRdeltaV-D and TCRgammaV-J junctional sequences were related to the development, therapeutic effectiveness and outcome in ALL.