CML患者CD4^+和CD8^+ T细胞的TCR Vβ基因谱系和克隆性分析

Analysis of TCR Vβ repertoire and clonality of CD4^+ and CD8^+ T cells in patients with CML

目的:了解慢性粒细胞白血病慢性期(CML-CP)患者外周血CD4+和CD8+T细胞中TCRVβ亚家族T细胞的基因表达和克隆性。方法:利用RT-PCR分别扩增19例CML-CP患者外周血单个核细胞(PBMCs)、CD4+和CD8+细胞TCRVβ亚家族基因的CDR3,阳性产物进一步经基因扫描分析其克隆性。结果:CML患者外周血CD4+和CD8+细胞分别表达部分(1～21个)Vβ亚家族,均以Vβ13的表达率最高,其次为Vβ9,多数患者的一些Vβ亚家族T细胞呈克隆性增殖,主要出现于CD8+细胞中,分别以Vβ21(CD4+)和Vβ11(CD8+)亚家族的克隆性增殖多见。结论:CML患者外周血CD4+和CD8+细胞的TCRVβ谱系均存在限制性分布,患者存在的克隆性增殖CD4+和CD8+T细胞可能与宿主抗CML抗原反应有关,它们可能在抗CML效应中起主要作用。

Objective ：To investigate the gene expression of TCR Vβ subfamily T cells and clonality in peripheral blood CD4^＋ and CD8^＋ cells from patients with chronic myelogenous leukemia - chronic phase （CML-CP）. Methods：The complementarity determining region 3 （CDR3） of TCR Vβ subfamily genes in peripheral blood mononuclear cells（ PBMCs）, sorted CD4^＋ and CD8^＋ cells from 19 CML-CP patients were amplified using RT-PCR, the products were further by genescan analysis to identify the clonality of T cells. Results：Only 1 to 21 Vβ subfamilies were detected in peripheral blood CD4^＋ and CD8^＋ cells from patients with CML. The most frequent expression of Vβ subfamily was Vβ13 followed by Vβ9. Clonal expanded T cells in some Vβ subfamilies could be identified in both CD4^＋ and CD8^＋ cells, especially in CD8^＋ cells. The clonal expanded of Vβ21 subfamily in CD4^＋ cells and Vβ11 subfamily in CD8^＋ cells were identified most frequently. Conclusion：The restricted distribution of TCR Vβ repertoire has been found in CD4^＋ and CD8^＋ cells in patients with CML. Clonal expanded CD4^＋ cells and CD8^＋ cells have been identified which may relate to host immune response to CML antigen and may play a important role in anti-CML effect.