In vitro stimulation of tumor necrosis factor production from rat splenocytes by cabbage extract

The effect of cabbage extract on in vitro production of tumor necrosis factor (TNF) was studied in primarily isolated rat splenocytes and peritoneal macrophages. Cabbage extract was found to stimulate the production of TNF in the cultured splenocytes, but not to do so in the cultured peritoneal macrophages. The production of TNF from peritoneal macrophages was significantly elevated by cabbage extract when these macrophages were co-cultured with isolated splenic T cells. The cytotoxic activities of the splenocytes stimulated with cabbage extract were significantly higher than those with vehicle control when the splenocytes were co-cultured with an ascites hepatoma cell line of AH109A. These results suggest that the stimulatory effect of cabbage extract on TNF production is indirect on macrophages and that T cells are involved in the appearance of the cabbage extract. They also suggest that in vitro anti-tumor activity is potentiated by cabbage extract through the stimulation of immune response.