[Effects of Dasatinib on the Expansion, Subsets, Receptor Expression and Cytotoxic Function of NK Cells in Vitro].

OBJECTIVE To investigate the effect of dasatinib on the expansion of NK cells in vitro, as well as the subsets, receptor expression and cytotoxic function of NK cells. METHODS Peripheral blood mononuclear cells (PBMCs) were isolated from healthy adult volunteers and cultured with SCGM added IL-2 and IL-15 for expansion of NK cells. In this culture system, dasatinib of different concentrations were added. Cell counting and phenotyping by flow cytometry were used to evaluate the amplification efficiency of NK cells. FCM was used to detect the expression of receptors on the surface of NK cells and the distribution of subsets. Subsequently, degranulation assay and CFSE/7AAD based cytotoxicity assay were used to detect the effects of dasatinib on NK cytotoxicity against leukemia cell line K562 cells. RESULTS The expansion efficiency of NK cells in vitro could be increased by dasatinib at the concentration range of 5-50 nmol/L, and the expansion efficiency of NK cells reached the peak at 20 nmol/L of dasatinib. The NK cytotoxicity against K562 cells in dasatinib cultured group at the concentration of 20 nmol/L was significantly higher than that in control group. For the cells cultured by disatinib in vitro, the MFI of CD226, NKP46 and NKG2D was up-regulated; the ratio of NKG2A+CD57- subset was down-regulated, while the ratio of NKG2A-CD57+ subset was up-regulated.The degranulation response of NKG2A-CD57+ NK cells to K562 cells was stronger than that of NKG2A+CD57- NK cells. CONCLUSION The results shows that appropriate dose of dasatinib(20 nmol/L) can increases the amplification efficiency of NK cells, simultaneously up-regulates the expression of NK activating receptors and increases the NKG2A-CD57+ subset, which lead to the enhancement of NK cytotoxicty against leukemia cell lines.