OBJECTIVETo observe the TCR V gamma gene repertoire diversity in the peripheral blood mononuclear cells of the patients with the chronic benzene poisoning.

METHODSComplementarity determining region 3 (CDR3) of TCR V gamma 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.

RESULTSAll V gamma subfamilies were detected in the 8 healthy donors. (1.30 +/- 0.48) V gamma subfamilies were detected in 10 patients. The number of detectable V gamma 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 V gamma genes in clonally expanded T-cells were V gamma II.

CONCLUSIONSkewed distribution and clonal expansion of TCR V gamma subfamily T cells could be found in the patients with the chronic benzene poisoning. This is the first report of clonal expansion TCR V gamma T cells in patients with chronic benzene poisoning. The bias pattern of TCR V alpha T cells may be due to the immune cytotoxicity from benzene.