Evaluation of the immune responses to extracts from Nymphaea rubra Roxb in rat dendritic cells

• Main Authors: Lee, Shau-Yu, 李曉芸
• Other Authors: Sheu, Shyang-Chwen
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/17531386772277746141

碩士 === 國立屏東科技大學 === 食品科學系 === 94 === Carbohydrates play a key role in enhancing immune function and facilitating cellular communication. Dendritic cells (DCs) are professional antigen presenting cells (APCs), which are pivotal for initiation of primary immune response. In this study, the regulatory effects of Nymphaea rubra Roxb polysaccharides (NR-PS) on maturation and function of cultured rat bone marrow derived DCs were investigated in vitro. Bone marrow hematopoietic cells (BMHC) were collected from 6-8 week-old rats. BMHC-imDC were grown from BMHC in complete RPMI media 1640 containing 20 ng/mL rGM- CSF and 10 ng/mL rIL-4. The cells enlarged and displayed typical stellate after cultivation for 7 days. An average of 3.8±1.50×107 cells/rat was obtained. BMHC-imDCs were stimulated with NR-PS (0, 3.125, 6.25, 12.5, 25, 50, 100 μg/mL) and 1 μg/mL LPS (positive control) for 48 h then analyzed for morphology, cell surface antigen, pinocytosis and cytokine concentration. BMHC-imDC treated with LPS and NR-PS displayed more stellate than control. The cell surface antigen and pinocytosis were analyzed by flow cytometer. The results indicated that 25 μg/mL of NR-PS could increase the co-expression of CD80/86 and MHC II molecules on the surface of DCs. Phagocytosis was assessed by the uptake of FITC–dextran. DC treated with 25 μg/mL of NR-PS showed lower dextran uptake ability than control, but it was not different from DCs/LPS. The secretation of IL-12, IFN-γ and IL-10 by DCs was analyzed by ELISA. While BMHC-imDCs treated with 25 μg/mL NR-PS secreted higher level of IL-12 and IFN-γthan control, BMHC-imDCs treated with 12.5-100 μg/mL NR-PS secreted lower level of IL-10 than control. The results demonstrated that NR-PS could not only promote the maturation of cultured rat bone marrow derived DCs in vitro, but also increase the secretion of IL-12 and IFN-γ which were associated with the differentiation of Th1 cells positioned downstream from DCs.