Study On Immunomodulation Of Opuntia Dillenii Haw. Polysaccharides

To investigate the immunomodulatory effects of Opuntia dillenii Haw. polysaccharides(OPS) on mice by experiments in vivo and in vitro.Using immunosuppressed mice which were induced by cyclophosphamide (Cy, ip.),phagocytesis of mononuclear macrophages (Mφ), alexin bypass way activity, intraseroushemolysin IgM level, intraserous IgG level, the proliferation of spenocytes and T lymphocytesubets in peripheral blood was used to investigate the immunomodulatory effects of OPS onimmune(non-specific and specific) of immunosuppressed mice. Using diabetic mice whichwere induced by multiple low dose streptozotocin (MLD-STZ, ip), phagocytesis ofmacrophages (Mφ), intraserous hemolysin IgM level, intraserous IgG level, the proliferationof spenocytes and T lymphocyte subets in peripheral blood was used to study the immuno-modulatory effects of OPS on immune (non-specific and specific) of STZ diabetic mice.The proliferation of spenocytes of mice and the metabolic activity, phagocytesis, Nitric Oxide(NO) production of mice peritoneal macrophages (Mφ) with OPS-Ⅰin vitro, were used toinvestigate the immunomodulatory effects of OPS-Ⅰon the activity of immune cells in vitro.Results as follow: (1) OPS of different dose by oral administration significantlyincreased the phagocytosis of macrophages from immunosuppression mice (P＜0.01). OPSsignificantly enhanced the activity of alexin bypass way in immunosuppression mice (P＜0.01), which extremely was beyond the normal group. OPS of different dose all extremelysignificantly increased intraserous IgM and IgG production in immunosuppression mice (P＜0.01).OPS(400 mg/kg) significantly enhanced the proliferation of T and B lymphocyte (P＜0.05) and all restored it to normal level. OPS (200,400 mg/kg) remarkedly reduced CD4~+T lymphocyte subset percentage and the ratio of CD4~+ and CD8~+ T lymphocyte of peripheralblood in immunosuppression mice (P＜0.05 or P＜0.01), and the effect of OPS presentsnegatively dose-effect relationship. OPS (200,400 mg/kg) remarkedly rose CD8~+ Tlymphocyte subset percentage (P＜0.05), and the effect of OPS presents positively dose-effect relationship. OPS (400 mg/kg) restored the ratio of CD4~+ and CD8~+ T lymphocyte tonormal level. The results indicated that OPS may enhance immunity through non-specificimmune, humoral and cell immune, regulating the ratio of CD4~+ and CD8~+ T lymphocyte inimmunosuppression mice.(2) OPS (400 mg/kg) by oral administration in mice extremely significantly increasedthe phagocytosis of macrophage from STZ diabetic mice (P＜0.01); OPS (200,400 mg/kg)all significantly increased intraserous IgM and IgG level in STZ diabetic mice (P＜0.05 orP＜0.01); OPS (400 mg/kg) is more effective and restored it to normal level. However, levamisole didn't significantly increase the content of intraserous IgG in STZ diabetic mice(P＞0.05). OPS didn't significantly enhance the proliferation of T lymphocyte, whichindicated the STZ diabetic mice that we established was T-lymphocyte-mediated diabeticmice. OPS (400 mg/kg) significantly enhanced the proliferation of B lymphocyte (P＜0.05)and restored it to normal level. OPS didn't significantly affected the CD4~+ T lymphocytepercentage in peripheral blood(P＞0.05), OPS (400 mg/kg) markedly rose CD8~+ Tlymphocyte percentage, reduced the ratio of CD4~+ and CD8~+ T lymphocyte(P＜0.05) andrestored these to normal level. Thus OPS could improve disorder immunity of STZ diabeticmice. The results indicated that OPS may enhance immunity and regulate disorder immunitythrough non-specific immune, humoral and cell immune, regulating the ratio of CD4~+ andCD8~+ T lymphocyte in STZ diabetic mice.(3) The major constituent of OPS, OPS-Ⅰextremely significantly derectly stimulatethe proliferation of spenocytes, enhanced the proliferation of T, B lymphocyte induced byConA and LPS, and which all present dose-effect relationship. OPS-Ⅰalso enhanced thephagocytic function, the metabolic activity and NO production of macrophage in mice. Theresults indicated OPS-Ⅰmay enhance non-specific immune, humoral and cell immune inmice, and OPS-Ⅰnot only has the effect ofcaryocinesia itself but also presents synergisticeffect with ConA and LPS.It is concluded that OPS may significantly enhanced the immunity of immuno-suppression mice and STZ diabetic mice through many approaches, many aspects. OPS is aimmunomodulator, and is able to regulate disorder immunity of STZ diabetic mice. Theexperiments in vitro indicate OPS can further enhance immunity through many aspects. Thespecific immunomodulatory mechanism of OPS needs futhure study.