Studies in the Immunomodulatory Effect of Herbal Polysaccharide on Mucosal Immunity

• Main Authors: Jui-Tai Yang, 楊瑞泰
• Other Authors: Rong-Tsun Wu
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/61756860427139327488

碩士 === 國立陽明大學 === 生物藥學研究所 === 93 === Abstract It has been found that Chinese herbal polysaccharides show diverse effect on immune cells in our laboratory. For example, polysaccharide could be used as an immunomodulator to down-regulate or up-regulate the immune system. In general of the immunomodulatory mechanism of Chinese herbal polysaccharides, which is hardly to penetrate the intestinal epithelium barrier or be taken up by the human body through oral administration due to its high molecular weight. Our hypothesis of a possible mechanism is that the polysaccharide influence on the intestinal epithelial cell or the antigen presenting cell below the epithelia cell, subsequencely affect the downstream T cells to enhance the development of immunity tolerance or to change the immunity response between TH1 pathway and TH2 pathway. In result, this could prevent the development of immune disorder. In this studing, two animal models were established. A rheumatoid arthritis animal model representing the TH1 immune disorder, and an asthma animal model representing the TH2 immune disorder. In both animal models, mice were fed with Dendrobill caulis polysaccharide (DeCaPS) to evaluate the potential of DeCaPS as an immunomodulator. In asthma animal model, the expressions of IgG1 and IgG2a were noticeably increased, and the splenocyte amplification ability was increased obviously in 250 mg/kg/day group. The splenocyte shows that the TH2 cytokine expression was not suppressed when mouse were fed with DeCaPS. In peyer’s patch, the expression of IFN-�� was increased when mice fed with 50 and 250 mg/kg/day but suppressed in 10 mg/kg/day group. In epithelia cells, there were no obvious changes of cytokine expression when mouse were fed with DeCaPS. As the result, the syndrome of TH2 immunity disorder is enhanced when mouse fed with DeCaPS. In the 60-day arthritis animal model, it was observed that the phenotype of arthritis was not very severe in the 10 mg/kg/day DeCaPS group. The change in the amount of CD4+CD25+ T cell indicate suppression of immune response was not different between control group and DeCaPS treated groups.In splenocyte the expression of IFN-���nwas well correlation with the phenotype of mice. In peyer’s patch, the expression of IFN-�� was increased in 50, 250 mg/kg/day group. The cytokine expression in lamina propria infer that the counter-balance effect of TH1/TH2 cytokine would not the major factor for curing cartilage-induced inflammation. Our result suggest that 10 mg/kg/day DeCaPS might suppressed the cartilage induced arthritis through modulation of TH1 immunity