Objective    To study the effect of survivin gene expression on the lymphocyte’s proliferation and function in cultured K562 cells.     Methods    The constructed recombinant vector pEGFP-C1-survivin and the plasmid pTZU6

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1-survivin encoding short hairpin RNA of survivin were transfected into K562 cells respectively to generate K562/survivin

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cells and K562/survivin

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cells. K562/survivin

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cells were selected by G418. The survivin mRNA and protein levels in the 3 kinds of cells (K562/survivin

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K562 and K562/survivin

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) were detected by semi-quantitative RT-PCR and immunohistochemistry methods. The peripheral blood mononuclear cells (PBMC) from healthy subjects were co-cultured with these 3 cells respectively in mixed lymphocyte-tumor cell culture (MLTC). Lymphocyte proliferation in the supernatant was evaluated by MTT assay. Nature killer activity was detected by flow cytometry and IFN-γ level was measured by ELISA assay.     Results    Proliferation index in K562/survivin

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group was much lower than that in the other 2 groups (P＜0.05). Survivin expression level was of negative correlation with NK activity. IFN-γ content in the MLTC of K562/survivin

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group was lower than that in K562 group (1/4.5) and K562/survivin

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group (1/8).     Conclusion    Enhanced expression of survivin may inhibit the proliferation of lymphocyte

activity of nature killer and the secretion of IFN-γ.