Modulation of Phagocytic Cell Phaocytosis and Reactive Oxygen Species Production by Bacteria Fermentation Product

• Main Authors: Wei-Chung Lin, 林韋君
• Other Authors: 賈景山
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/25882521114299423447

碩士 === 國立臺灣大學 === 微生物學研究所 === 96 === Phagocytosis is the first line of host defense against pathogens and is mediated by phagocytes including macrophages and neutrophils. The foods fermented products of lactic acid bacteria have the capacity to modulate immune function. In animals feeding with lactic acid bacteria fermented products, the phagocytic activity of peripheral blood mononuclear cells could be enhanced. In this study, we established an in vitro phagocytosis assay to investigate whether a soybean fermented has a direct phagocytosis-stimulating effects. After intra-peritoneal injected with 4% thioglycollate overnight, Balb/c mice were sacrificed and the peritoneal cells, neutrophils and macrophages were collected. Following stimulation with soybean fermented product, these phagocytic cells were challenged with GFP-expressed E. coli. Phagocytosis was semi-quantitated by flow cytometry at different time intervals. In parallel experiments, ROS production by primary phagocytes or cell lines was measured by H DCFA. The fermented products or its fractions harboring componnts greater than 50 kDa could enhance the phagocytic ability of mouse phagocytes or human macrophage cell line, THP-1. On the other hands, the fractions less than 50 kDa could inhibit LPS- or bacteria-induced ROS production in mouse phagocytes or THP-1. The results indicated that the soybean fermented product exhibit complex activities from enhancement of the phagocytosis to the regulation of oxidative stress in phagocytic cells.