慢性苯中毒患者外周血T细胞TCRVγ基因多样性分析

Analysis of TCR Vγ gene diversity from peripheral blood in patients with chronic benzene poisoning

目的了解慢性苯中毒患者外周血T细胞的TCR Vγ基因谱系多样性和克隆性增殖特点。方法利用反转录-聚合酶链反应（RT-PCR）方法扩增10例慢性苯中毒患者外周血单个核细胞中3个TCR Vγ基因，PCR产物进一步经荧光标记和基因扫描分析T细胞克隆陛，并与8例健康人进行比较。结果8例健康人外周血T细胞检测到所有Vγ亚家族，10例慢性苯中毒患者平均表达（1．30±0．48）个Ⅵ亚家族，较健康人明显减少，差异有统计学意义（P〈0．01）。慢性苯中毒患者出现克隆性增殖改变比较集中在VγⅡ亚家族。结论慢性苯中毒患者外周血出现TCR Vγ亚家族倾斜性分布和克隆性增殖T细胞，这可能是苯中毒后所引起的机体特异性免疫反应。

Objective To observe the TCR Vγ gene repertoire diversity in the peripheral blood mononuclear cells of the patients with the chronic benzene poisoning. Methods Complementarity determining region 3 （CDR3） of TCR Vγ subfamily genes were amplified in 10 patients with the chronic benzene poisoning using RT-PCR. The PCR products were further analyzed by genescan to evaluate clonality of T cells. 8 healthy persons served as control. Results All Vγ subfamilies were detected in the 8 healthy donors. （ 1.30± 0.48） Vγ subfamilies were detected in 10 patients. The number of detectable Vγ subfamilies present in the patients with the chronic benzene poisoning was significantly lower than in the control group （P〈0.01）. The most frequently used Vγ genes in clonally expanded T-cells were Vγ Ⅱ. Conclusion Skewed distribution and clonal expansion of TCR Vγ subfamily T cells could be found in the patients with the chronic benzene poisoning, This is the first report of clonal expansion TCR Vγ T cells in patients with chronic benzene poisoning. The bias pattern of TCR Vet T cells may be due to the immune cytotoxicity from benzene.