Enhancement of the Cytotoxic Effect of Cytokine-Induced Killers by Dendritic Cells Derived from Umbilical Cord Blood

To define the strong anti-tumor responses of the cytokine-induced killers (CIK) by mature dendritic cells derived from umbilical cord blood (CBDC),at time of 12 days cultivation,the morphology of CBDC was examined with electron microscopy,and their phenotype was analyzed by flow cytometry. The proliferative activities CIK activated by CBDC were tested at different times of cultivation by means of 3 H-TdR incorporation method,and its anti-tumor effects on BEL-7402 hepatic cancer cells were checked with MTT method. It was found that the morphologically typical CBDC were induced in vitro,which expressed the MHC I and II molecules (HLA-A,B,C and HLA-DR) and CD54 (ICAM-1) at high magnitude,and also CD80,CD83,CD1a,but not CD68. After the in vitro cultivation for 12 days,CBDC could enhance the proliferation of CIK at highest rate with a mixture radio of these two cells of 1:10,at which the activated CIK showed the highest cytotoxic effect on the BEL-7402 hepatic cancer cells with a best effector-target radio of these two cells of 80∶1.