目的 探讨IgH和Vδ2Dδ3基因重排在初诊儿童急性淋巴细胞白血病(ALL)中的分布频率及其在中枢神经系统白血病(CNSL)早期诊断与脑脊液(CSF)微量残留病(MRD)监测中的意义。方法 对初诊ALL患者的骨髓标本及不同病期CSF标本采用聚合酶链反应(PCR)检测IgH基因重排和巢式聚合酶链反应(Nested-PCR)检测Vδ2Dδ3基因重排。结果 32份ALL患者骨髓标本中有23份存在克隆特异性IgH基因重排和／或Vδ2Dδ3基因重排。在骨髓标本存在异常基因重排的诱导缓解治疗期患儿的23份CSF中，9份检出Vδ2Dδ3基因重排，4份检出IgH基因重排。而完全缓解期患儿的37份CSF中，3份检出IsH基因重排，7份检出Vδ2Dδ3基因重排。结论 在所检初诊ALL患者的骨髓标本中，IgH重排片段的阳性检出率为47％，Vδ2Dδ3基因的阳性检出率为38％；ALL患者脑脊液中ISH和Vδ2Dδ3基因重排的PCR动态监测较CSF常规、生化及细胞学检测更灵敏，更有助于CNSL的早期诊断，对CNSL的预防及预后的判断有指导意义。

Objective The purpose of this paper was to study the distribution frequency of immunoglobulin heavy chain gene(IgH) and T cell receptor (TCR)Vδ 2Dδ 3 gene rearrangement in children with acute lymphoblastic leukemia(ALL) in the first visit and the significance in early diagnosis of central nervous system leukemia(CNSL) and monitoring of MRD in CSF.Methods PCR and Nested-PCR techniques were employed to amplify IgH and TCR Vδ 2Dδ 3 fragments from blast cells in bone marrow and from CSF of patients with ALL.Results Twenty three of 32 patients had IgH gene rearrangement and/or TCR Vδ 2Dδ 3 gene rearrangement in bone marrow samples.Nine of 23 CSF samples from patients during remission induction had TCR Vδ 2Dδ 3 gene rearrangement and 4 samples had IgH gene rearrangement. Three of 37 CSF samples from patients in complete remission had IgH gene rearrangement and 7 samples had Vδ 2Dδ 3 gene rearrangement.Conclusions The positive rate of IgH gene rearrangement is 47% and that of Vδ 2Dδ 3 gene rearrangement is 38% in detected samples of bone marrow. Dynamic detection of IgH and Vδ 2Dδ 3 gene rearrangements in CSF of ALL patients by PCR techniques is an effective tool for early clinical diagnosis of CNSL and much more sensitive than CSF routine examination.It plays a guiding role in prevention and prognosis evaluation of CNSL.