Immune Effect of DC-CIK Cells against Leukemia K562 Cells In Vitro

Objective To investigate the immune effect of DC-CIK cells,obtained by co-culture of cytokine-induced killer(CIK) cells and dendritic cells(DCs),against leukemia K562 cells in vitro.Methods Normal human peripheral blood mononuclear cells(PBMCs) were isolated and induced with cytokines to obtain DCs and CIK cells which were co-cultured for 3 d.The obtained DC-CIK cells were determined for proliferative activity by MTT method and for phenotype by flow cytometry,then used as effecter cells,while PBMCs,DCs and CIK cells as controls,and K562 as target cells.The cells in various groups were determined for killing activity by MTT method,and for IL-17 level in culture supernatant by ELISA.Results Compared with PBMCs,DCs and CIK cells,DC-CIK cells proliferated rapidly.The harvested cells after co-culture were mainly DCs,in which CIK cells were mainly lymphocytes with killing effect.The killing activity to K562 cells,as well as secreted IL-17 level,of DC-CIK cells were significantly higher than those of cells as controls(P 0.05).Conclusion DC-CIK showed killing effect on K562 cells through cytokine secretion.