OBJECTIVETo compare several schemes of inducing and expanding the antibody-mediated high efficiency CIK (AMHE-CIK) in vitro, so as to find out a method that can acquire a large number of cells capable to kill the tumor cells in a short time.

METHODSPeripheral blood mononuclear cells (PBMNC) from healthy volunteers was isolated and activated with CD3 antibody, then were cultured with the addition of different cytokines (IL-2, IL-4, G-CSF, GM-CSF, IFN-γ, TNF-α) for 14 days in vitro. The morphological changes of cells were observed by light microscopy. Based on the immunophenotypes of cells in each groups analyzed by flow cytometry, the cytokines capable to induce the dendritic cells and killer cells were screened out, respectively. According to different combination of cytokines, the cells were divided 4 groups: control, IL-2, group 1 (componant A included IL-2, IL-4, and GM-CSF. Componant B included IL-2, G-CSF, IFN-γ, and TNF-α), and group 2 (componant A included IL-2, IL-4, and GM-CSF. Componant B included IL-2, IL-4, G-CSF, IFN-γ, and TNF-α). The proliferation and differentiation of CD3(+) CD8(+) and CD3(+) CD56(+) cells were measured by flow cytometry after culture in vitro for 7 days.

RESULTSAfter inducing and expanding in vitro for 7 days, the cell proliferation rate of control group, IL-2 group, group 1 and group 2 were 1.57 ± 0.01, 4.17 ± 0.16, 5 ± 0.47, 7.17 ± 0.24-folds, respectively. The differences between IL-2 group, group 1, group 2 and control group were statistically significant (P < 0.05). The immunophenotype analysis showed that the proportion of CD3(+) CD8(+) induced by each protocol was 13.96 ± 0.23%, 26.33 ± 0.55%, 36.83 ± 0.34% and 35.88 ± 0.16%, respectively. The proportion of CD3(+) CD8(+) in group 1 and 2 was higher than that in IL-2 group (P < 0.05), but the difference between them was not significant (P < 0.05). The proportions of CD3(+) CD56(+) induced by each protocol were 11.03 ± 0.28%, 29.31 ± 0.60%, 39.96 ± 0.38% and 29.33 ± 0.54%, respectively, the proportion of group 1 was higher than that of IL-2 group and group 2 (P < 0.05), but the difference between IL-2 group and group 2 was not significant (P < 0.05).

CONCLUSIONThe group 1 protocol obtained from this study can promote the proliferation of DC-CIK and also increase the proportion of the tumor killing cells (CD3(+) CD8(+) and CD3(+) CD56(+)).