Tumor antigen loading DC
SK-N-SH cells in logarithmic phase were resuspended and adjusted to 2×107/ml concentration. Cells were quickly frozen to -80℃, then rewarmed in 37℃ water. After four cycles, cells suspension was centrifuged with 10,000 r/min for 15 minutes and the supernatant was collected and cryopreserved at -80℃. The lysate equivalent to 2×106 tumor cells was added into per millilite rmedium of DCs and cultivated for 6 days. Four hours later, cells suspension was added rmTNF-α and cultivated to 7th day. Then, the suspension cells were collected and defined tumor antigen loaded DCs. The cell morphology of DCs was observed by phase contrast microscope. Meanwhile, the expression rate of CD11c, CD86 and MHC-II were detected by flow cytometry.