Involvement of Tumor Necrosis Factor in Human Granulocyte-Mediated Killing of WEHI 164 Cells

Human polymorphonuclear leukocytes (PMNLs) kill WEHI 164 clone 13 cells in an 18-hour 51Cr release assay. Antibody to human tumor necrosis factor (TNF) blocks the lysis of targets mediated by human granulocytes. PMNLs triggered by sensitive targets not only displayed cytotoxic activity, but also released a soluble factor capable of selectively lysing WEHI 164 cells. The killing of these cells by supernatants of triggered granulocytes was totally inhibited by anti-TNF antibody. These experiments suggest that the killing of WEHI 164 sarcoma cells by human PMNLs involves TNF or TNF-like molecules.