Sensitized dendritic cells with apoptotic hepatoma cells induced by mitomycin

Gang WU; Benli HAN; Xuetao PEI

ABSTRACT

BACKGROUND:

Dendritic cells play an important role in antigen present in vivo, and the mechanism of tumor cells in escaping the antigen presentation of dendritic cells existed in the patients with tumor.

OBJECTIVE:

To sensitize dendritic cells from human peripheral blood with apoptotic hepatoma cells induced by mitomycin.

DESIGN:

A randomized control trial by taking apoptotic hepatoma cell sensitized dendritic cells as the observed subjects.SETTINGS Institute of Field Surgery, Daping Hospital, the Third Military Medical University of Chinese PLA; Institute of Radiation Medicine,Chinese PLA Academy of Military Medical Sciences.MATERIALS The experiments were carried out in the Institute of Radiation Medicine, Chinese PLA Academy of Military Medical Sciences from April 1998 to May 1999. The cell strain was the QBC939 bile duct cancer cell strain, and mitomycin was used as the antitumor drug.

METHODS:

Mononuclear cells were isolated from the peripheral blood of normal people, 50μg/L granulocyte-macrophage colony stimulating factor(GM-CSF) and 1 000 U/mL interleukin-4 (IL-4) were added, once every other day for 4 times. On the 3rd day of culture, the apoptotic bile duct cancer cells induced by mitomycin was added, and then cultured in vitro for 4 days, finally the dendritic cells were collected.MAIN OUTCOME

MEASURES:

① The identification of the cultured dendritic cells was observed; ② The dendritic cells were co-cultured with necrotic and normally cultured bile duct cancer cells respectively, and the phagocytized apoptotic body loaded antigens were observed; ③ The immunostimulatory activity of dendritic cells (1×103, 5×103 and 1×104/well)and that after loaded by antigen were detected, and the mononuclear cells were taken as controls.

RESULTS:

① The cultured and amplified dendritic cells expressed high levels of costimulatory molecules of CD1a and B7, and there were typical irregular processes on the surface. ② The tumor cells formed apoptotic bodies when they were induced by mitomycin, which were arrested and phagocytized by dendritic cells. ③ The ability of the antigen loaded dendritic cells in stimulating the proliferation of allogenic lymphocyte T was further enhanced.

CONCLUSION:

The apoptotic tumor cells induced by mitomycin can induce the mononuclear cells from human peripheral blood differentiating into the dendritic cells with the concomitance of GM-CSF and recombinant IL-4 and amplify dendritic cells. Meanwhile, the dendritic cells can effectively present the antigens of apoptotic bile duct cancer cells, and it probably becomes a new effective approach for tumor antigen to sensitize dendritic cells.