Increasing TCR Zeta Expression and Maintaining the Clonality of T Cells from AML Patients after IL-2, IL-7 and IL-12 Induction

T-cell immunodeficiency is a common feature in patients with leukemia, lower activation of T cells was one of reasons. The TCR zeta chain has emerged as a key subunit of the T-cell antigen receptor, which plays a central role in the signal-transducing events leading to T cell activation. The proliferation and activation of T cells may be inducted by T cell related cytokines. In this study, we explored the change of TCR zeta gene expression and the clonality of T cells after induction with different immune cytokines, including IL-2, IL-7 or IL-12. CD3⁺ T cells sorted from peripheral blood of 4 cases with AML were induced with different immune cytokines, including IL-2, IL-7, IL-12, anti-CD3 and anti-CD28 antibodies in vitro. The expression levels of TCR zeta gene and related genes in T cells before and after induction were then analyzed by fluorescence quantitative RT-PCR. The distribution and clonality of TCR Vβ subfamily T cells were analyzed by RT-PCR and Genescan techniques. Increasing expression levels of TCR zeta gene and zap-70 (TCR zeta chain associated-protein) gene in CD3+T cells from AML patients were found after induction with single stimulating factor or the combination with different cytokines, while the expression of FcεRIγ (TCR ζ gene complementary factor) was down-regulated. We further compared the T cell clonality in CD3+T cells from AML patients after cytokine induction, eight to 22 TCR V β subfamilies could be detected in T cells from AML cases, most of them displayed polyclonal expansion. The number of expressed TCR Vβ subfamilies was increased without the change of clonality in T cells induced by CD3+CD28+IL7. In conclusion, TCR zeta gene and its related genes could be upregulated through induction with different cytokine combination such as IL-2, IL-7 and IL-12, therefore to improve the T cell activation in patients with AML. And the main effect of cytokines might to maintain the T cell clonality and nonspecific amplification of T cell clones. Further investigation can be designed to amplify the specific anti-AML TCR Vβ clones using AML associated antigens and such cytokine combination.