T-Bet Mediated Anti-Neoplastic Effects of Dendritic Cell-Cytokine Induced Killer Cells in vitro

Objective: to investigate the molecular mechanism underlying t-bet mediated anti-neoplastic effects of cytokine induced killer (cik) cells.methods: lymphocytes isolated from peripheral blood of leukemic children were induced with g- interferon (ifn-g), cd3mcab and interluki-2 (il-2), and co-cultured with dendritic cells (dcs) to generate dc-cik cells.the morphology and immunophenotype of these cells were determined by a light microscopy and flow cytometry, respectively. il-2 and ifn-g levels released by dc-cik cells were quantified by elisa. cytotoxicity of dc-cik cells against leukemia cell lines was measured by mtt assay. fcm was used to detect cd4+cd25+treg cells, while rt-pcr and western blot were used to determine mrna and protein expressions of foxp3 and gata3 in dc-cik cells treated with t-bet monoclonal antibody.findings: induced dc-cik cells were regular, round and transparent with variable cell volume and cellular aggregation.the main effector cells in this population were cd3+cd8+ cells and cd3+cd56+ cells.we demonstrated a time dependent increase in il-2 and ifn-g levels after induction. dc-cik cells were cytotoxic to b95 cells, jhhan cells and m07e cells, with the highest cytotoxicity towards b95 cells. treatment with mouse anti-human t-bet monoclonal antibody resulted in an increase in the proportion of cd4+cd25+treg cells and elevation of foxp3 and gata3 mrna and protein levels.conclusion: dc-cik cells induced with cytokines were strongly cytotoxic towards a number of cancer cell lines.foxp3 and gata3 were implicated in the t-bet mediated anti-neoplastic effects of dc-cik cells via activation of the th1 pathway and suppression of the th2 and treg pathways