Enterococcus faecalis FK-23株加熱死菌体標品を経口摂取した無菌マウスにおける腫瘍壊死因子産生能の増強 Increases in Production of Tumor Necrosis Factor in Germ-Free Mice Fed Enterococcus faecalis FK-23 Preparation
The effects of a preparation of heat-killed cells of Enterococcus faecalis FK-23 taken orally on the production of tumor necrosis factor (TNF) were examined in germ-free, and SPF ICR mice. These mice had TNF in their sera 1h after an intravenous injection of the FK-23 preparation or bacterial lipopolysaccharide. The mean TNF level in germ-free mice after the injection was significantly higher at day 0 after the mice ate feed containing the FK-23 preparation on days-7 to -3, with the usual feed given afterward until day 0. In the SPF ICR mice, TNF production was not changed when feed containing the FK-23 preparation was given. These results indicate that the oral intake of the FK-23 preparation had immunomodulating effects.