[Role of natural killer cells in the antimetastatic effect of defibrinogenation with batroxobin].

The antimetastatic effects of defibrinogenation with batroxobin were investigated in normal mice and in mice with depressed or activated natural killer (NK) cell activity. Batroxobin inhibited the formation of lung metastases after intravenous inoculation of the F10 subline of B16 melanoma. Inhibition of NK activity by treatment of mice with anti-asialo GM1 antibody abrogated the antimetastatic effects of Batroxobin. Conversely, augmentation of NK cell activity by poly I:C plus treatment with batroxobin produced additive antimetastatic effects. Studies on the mechanism of interaction between Batroxobin and NK cells revealed that Batroxobin treatment did not affect splenic NK activity in vitro. From these data, it was found that the antimetastatic effects of batroxobin are dependent on the level of NK activity in the host.