香菇多糖对鲤鱼（cyprinus carpio）离体培养免疫细胞的活性调节作用*

采用Percoll密度离心等技术，对鲤鱼的头肾巨噬细胞和外周血白细胞进行分离纯化，并离体培养。体外暴露不同浓度的黄芪多糖（APS）和香菇多糖（LNT）后，分别采用 MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide)法测定它们对鲤鱼外周血白细胞增殖的影响；NBT(nitroblue tetrazolium)还原法和Griess试剂显色法测定对头肾巨噬细胞的呼吸爆发的影响；实时定量PCR法测定头肾巨噬细胞细胞因子IL-1β诱导表达的影响。结果显示，香菇多糖能显著诱导巨噬细胞的氧爆发活性；其低浓度时对细胞的氮呼吸爆发活性无显著影响，随着作用浓度的增加表现为高浓度抑制作用；香菇多糖可以显著促进鲤鱼外周血白细胞的增殖，且能显著增强IL-1β的体外诱导表达。结果表明香菇多糖对离体培养鲤鱼免疫细胞有明显活性作用，对鲤鱼非特异性免疫和特异性免疫具有促进作用，是一种有潜力的鱼用免疫增强剂。

Effect of Lentinan on the Activation of Immunological Cell Culture In vitro in Cyprinus carpio

The head kidney macrophages and peripheral blood granulocytes isolated from the head kidney of Cyprinus carpio were purified by means of Percoll gradient density centrifugation and were exposed to Lentinan in vitro. The effects of the polysaccharide on the peripheral blood granulocytes proliferation, respiratory burst of macrophage and IL-1βmRNA expression of macrophages were investigated by using MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) ,NBT(nitroblue tetrazolium) reduction, Griess reagent coloration and Real time PCR respectively, to evaluate the immunostimulant of the polysaccharide and compare its immune activities with the control group. Results showed that Lentinan stimulated markedly the proliferation of the peripheral blood granulocytes and could induce superoxide anion in macrophages markedly. Lentinan had no conspicuous effect on nitrogen burst activity of macrophages, moreover it inhibited the nitrogen burst activity at higher doses. The polysaccharide stimulated IL-1βexpression in carp head kidney . It is suggested that Lentinan could modulate the immune response of Cyprinus carpio.