The T-cell receptor Vbeta gene repertoire and clonal expansion from peripheral blood T cells in benzene-exposed workers in China.

The toxicity of benzene to lymphocytes is well known; however, little is known about the variety of T-cells that are rearranged after benzene exposure. In order to further understand the relative toxicity of benzene on T-cells, we investigated the features of the complementarity determining region 3 (CDR3) of T cells from benzene exposed workers. CDR3 of the T-cell receptor variable beta-chain (TCRVbeta) subfamily genes were amplified using reverse transcriptase-polymerase chain reaction. The polymerase chain reaction products were further subjected to genescan analysis to evaluate the clonality of T cells. Results revealed 2-12 Vbeta subfamilies identified in 16 benzene-exposed workers. The number of detectable Vbeta subfamilies present in the benzene-exposed group was significantly lower than in the control group (p<0.05). The most frequently used Vbeta genes were Vbeta3, Vbeta21, Vbeta6, and Vbeta16. We observed a skewed distribution and clonal expansion of TCR Vbeta subfamilies in benzene-exposed workers.