[Induction of tumor necrosis factor (TNF) by OK-432]

The induction of tumor necrosis factor (TNF) by OK-432 was investigated. The results were as follows: Serum from OK-432 injected into NZW rabbits treated with LPS was cytotoxic to tumor cells in vitro. With respect to the target cell spectrum this factor was cytotoxic to L929, Lewis, M7609 and K562, but not to Chang liver cells, HMV cells or HeLa cells. The cytotoxic activity of this factor was found to be M.W. 48,000 on H.P.L.C., and the pI was revealed to be 5.4 by isoelectric focusing. These results were consistent with previously reported findings on TNF.