Cytostatic and tumoricidal activities of tumor necrosis factor-treated neutrophils.

When incubated with recombinant human tumor necrosis factor (TNF), polymorphonuclear neutrophils (PMN) were highly cytostatic to all three tumor cell lines tested. The cytostasis was dose-dependent for both PMN and TNF, and could be neutralized by antibodies specific for TNF. It could also be abrogated by catalase but not by superoxide dismutase (SOD), suggesting that the hydrogen peroxide generated by the TNF-activated PMN was involved in the cytostasis. TNF-treated PMN were also cytotoxic to the tumor cells. However, high level of tumor cytolysis was not evident until after long (greater than 24 h) incubation.