Effect of tuftsin on human Kupffer cell

BACKGROUND/AIMS: Kupffer cells are the most important category of reticuloendothelial cells which are critical for host defense in the liver. We investigated the effects of tuftsin (Thr-Lys-Pro-Arg) on human Kupffer cells. METHODOLOGY: Human Kupffer cells were obtained from the livers of patients with colon cancer. Phagocytosis assay was done by microscopic counting of the number of Kupffer cells that engulfed fluorescent particle(s), and the number of the particles engulfed per Kupffer cell when Kupffer cells were incubated with and without tuftsin. Effect of tuftsin on the release of tumor necrosis factor from Kupffer cells was also studied. RESULTS: Phagocytosis was enhanced significantly by tuftsin. The greatest effect on percentage of phagocytic cells was observed at 1.0 microg/ml of tuftsin. The mean number of particles engulfed per Kupffer cell was also increased with tuftsin 1.0 microg/ml. Tumor necrosis factor release was also significantly increased; the greatest effect was observed at 1.0 microg/ml of tuftsin. CONCLUSIONS: Tuftsin enhances phagocytic activity and tumor necrosis factor release of human Kupffer cells, which are advantageous for host defense against invading microorganisms and tumor cells.