['We aimed to investigate whether allogeneic dendritic cells pulsed with alpha-galactosylceramide (DCG) treatment induces activation of Natural Killer T (NKT) cells.', 'C57BL/6 and BALB/c mice were injected with syngeneic and allogeneic DCG. We then examined NK and NKT cell activity in the lung and spleen and antitumor effect in various lung tumor metastatic models.', 'While splenic NKT activity was suppressed after allogeneic DCG treatment, allogeneic DCG treatment induced similar antitumor effect as well as lung NKT and NK cell activity compared to syngeneic DCG treatment. Furthermore, allogeneic DCG treatment prolonged survival in B16F10, LLC, Pan02, MethA, and CT26 tumor models in two strains of mice.'] Do allogeneic DCG promote lung NK cell activation and antitumor effect after invariant NKT cell activation?