Effects of CD 40-pulsed tumor specific dendritic cells on biological activity of cytokine-induced killer cells

Objective:To investigate the changes of phenotypes,proliferation activity and cytotoxicity of cytokine-induced killer(CIK) cells after co-cultured with autologous dendritic cells sensitized by CD 40-pulsed apoptotic tumor cells.Methods:DCs and CIK cells were induced from peripheral blood mononuclear cells(PBMC) of healthy subjects by the regular method.The immature DCs were loaded with apoptotic tumor cells pulsed with or without CD 40 mAb.The mature DCs were co-cultured with CIK cells for 5 d to obtain DC40Ag-CIK cells and DCAg-CIK cells.The proliferative activity of the effector cells was observed.Cell phenotypes were analyzed by flow cytometry.The level of interferon IFN-γ in the supernatant of cultured cells was measured by enzyme-linked immunosorbent assays(ELISA).The cytotoxicity was detected by [3H]TdR incorporation method.Results:The expression rates of CD 1a,CD 80,CD 83,CD 86,and HLR-DR were up-regulated in DCs after loaded with apoptotic tumor cells.CD 40 mAb-pulsed apoptotic tumor cells further induced maturation of DCs.On the 14th day the DC40Ag-CIK cells,DCAg-CIK cells,and CIK cells proliferated and expanded(18.2±1.7) times,(15.0±1.2) times,(9.3±1.8) times,respectively.The proportion of CD3+CD56+ cells was markedly up-regulated in DC40Ag-CIK cells compared with DCAg-CIK cells and CIK cells(P0.05).The cytotoxicity of DC40Ag-CIK cells and DCAg-CIK cells on A 549 cells was enhanced compared with CIK cells(P0.05).DC40Ag-CIK cells had much stronger cytotoxicity than DCAg-CIK cells(P0.05).The level of IFN-γ was(1 494.7±246.3),(2 706.3±197.0),and(3 676.3±335.0) pg/mL in the supernatant of CIK,DCAg-CIK,and DC40Ag-CIK cell cultures,respectively.Conclusion:DCs loaded with apoptotic tumor cells pulsed by CD 40 could further enhanced the proliferative activity and cytotoxicity of CIK cells compared with those without CD 40 pulsation.