Induction of lymphokine-activated cytotoxic T lymphocytes stimulated by dendritic cells and autologous tumor from a patient with gastric cancer and their effects in vitro.

Background/aims: The purpose of the study was to generate lymphokine-activated cytotoxic T lymphocytes stimulated by dendritic cells (DC) and autologous tumor from a patient with gastric cancer and to clarify their cytotoxic effects in vitro.

Methodology: DC was induced by interleukin-4 (IL-4) and granulocyte-macrophage-colony-stimulating factor (GM-CSF) from the peripheral blood mononuclear cells (PBMC). Then, PBMC was incubated with mitomycin C-treated tumor cells and DC, and following that was activated with IL-2 and anti-CD3. Induction of DC and cytotoxic T cells (CTL) were confirmed by the analyses of the cell surface antigens, killing activities, and blocking tests.

Results: Induction of DC and cytotoxic T cells (CTL) was confirmed by the analyses of the cell surface antigens, killing activities, and blocking tests. In vitro study demonstrated that lymphokine-activated lymphocytes pulsed by DCs and autologous tumor contained the largest population of CTLs, the greatest production of IFN-gamma, and the greatest ATK activity.

Conclusions: Those results indicated that CTLs could be generated in vitro from a patient with gastric cancer more successfully by this method than by conventional methods, suggesting the possibility of a new immunotherapy for the treatment of gastric cancer.