Immunomodulatory effects of Fomes fomentarius polysaccharides: an experimental study in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the immunomodulatory effects of Fomes fomentarius polysaccharides (FFP) in mice.</p><p><b>METHODS</b>MTT assay was employed to evaluate the in vitro metabolic activity of the mouse splenocytes treated with FFP at different concentrations, and the secretion of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (INF-gamma) and interleukin 2 (IL-2) from the cells were measured by enzyme-linked immunosorbent assay. The changes in the phagocytotic activity of mouse macrophage in response to FFP treatment were evaluated by phagocytosis percentage of chicken red blood cells (CRBCs). The effect of FFP on the humoral immunity was assessed in mice immunized with sheep red blood cells (SRBCs) by measuring the serum levels of specific antibody (hemolysin) against SRBCs.</p><p><b>RESULTS</b>FFP at the concentrations of 25, 50, and 100 microg/ml all significantly enhanced the metabolic activity of mouse splenocytes in vitro and increased the production of TNF-alpha, IFN-gamma and IL-2. FFP treatment also markedly enhanced the metabolic activity of mouse peritoneal exudate cells and TNF-alpha production by the cells. At the doses of 25, 50, and 100 mg/kg, FFP significantly increased serum hemolysin level in mice immunized with SRBCs, and FFP at 50 and 100 mg/kg obviously increased the capacity of mouse peritoneal macrophages in vivo for CRBC phagocytosis.</p><p><b>CONCLUSION</b>FFP can promote the secretion of TNF-alpha, IFN-gamma and IL-2 by mouse immunocytes and enhance mouse humoral immune response and the phagocytotic activity of the macrophages.</p>

Effects of lipopolysaccharides of Bacterium prodigiosum on tumor growth and immunosuppression in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of lipopolysaccharides of Bacterium prodigiosum (BP-LPS) in inhibiting tumor growth and improving immunosuppression in mice.</p><p><b>METHODS</b>In mice bearing S180 tumor and a mouse model of immunosuppression induced by cyclophosphamide (CTX), the tumor growth, indexes of the immune organs and peripheral white blood cell count were measured after intraperitoneal injection of BP-LPS.</p><p><b>RESULTS</b>Injections of BP-LPS (40 U/kg) for 8 consecutive days resulted in a significant inhibition of the tumor growth in mice bearing S180 tumor (P<0.01), with a dose-dependent increase of the spleen indexes but no obvious changes in the thymus indexes. Intraperitoneal injections of BP-LPS for 7 days inhibited the reduction of peripheral white blood cells and spleen indexes in immunosuppressive mice, but did not produce any significant changes in normal mice.</p><p><b>CONCLUSION</b>BP-LPS can inhibit the tumor growth in tumor-bearing mice and enhance the immune functions of immunosuppressive mice.</p>

Trehalose Production by Permeabilized Cells / 微生物学通报

A permeabilization method of Micrococcus cells has been established. The obtained penneabilized cells could be used for several batches and in the mean time the intracellular enzymes still keep high activity. This method will undoubtedly increase the productivity of the cells and cut down the cost; therefore, it will be a promising way in the treha-lose industrialization. The experiment shows: after being treated with 5% (v/v) methylbenzene for 40min, the cells in suspension were converted into permeabilized cells, then the latter acted on 10% liquefied starch to produce trehaloae, the conversion ratio could reach 70%. The penneabilized cells could be used at least for 6 batchs (12h per batch) and the intracellular enzyme activity kept steady.