ABSTRACT
AIM: To investigate the distribution and clonal expansion of TCR V? subfamily T cells in patients with acute monoblastic leukemia (M5). METHODS:The CDR3 of TCR V? 24 subfamily genes were amplified in peripheral blood mononuclear cells from 9 cases with M5 using RT-PCR and the PCR products were further labeled with fluorescent and analyzed by genescan technique for the CDR3 size, to evaluate clonality of the detectable TCR V? T cells. RESULTS:Only 1-10 V? subfamily T cells were identified in M5 cases. Genescan analysis showed that oligoclonal (clonal expansion) T cells were found in some V? subfamilies from 8 cases with M5, V? 2 oligoclonal T cells were identified in six cases, whereas V? 7- or V? 9 clonal expansion T cells were detected in the other two cases, respectively. In addition, except V? 2, V? 7 or V? 21 oligoclonal T cells could be detected in two cases, respectively. CONCLUSION:The skew distribution and clonal expansion of TCR V? subfamily T cells could be found in patients with M5. It may be a specific anti-leukemia immune response with which the host T cells were activated by the leukemia-associated-antigen. The clonal expansion T cells were tendentious in V? 2, which may be related to the M5 leukemia cells associated antigen.