中药多糖对柔嫩艾美尔球虫感染鸡细胞因子水平的影响(英文)

EFFECT OF HERBAL POLYSACCHARIDES ON CYTOKINE PRODUCTION IN CHICKENS INFECTED WITH EIMERIA TENELLA

本文选用天然免疫活性多糖-香菇(Lentinus edodes)、银耳(Tremella fuciformis Berk)和黄芪(Astragalus membranaceus Bge)多糖,研究其对柔嫩艾美尔球虫感染鸡细胞因子IFN-γ和IL-2水平的影响。选择180只雏鸡并将其随机分为9组:3个多糖提取物添加组(LenE、TreE和AstE),3个添加提取物并免疫接种疫苗组(LenE+V、TreE+V和AstE+V),1个球虫免疫组和2个对照组(球虫感染组和非感染组)。检测球虫感染后第7、14天鸡血清IFN-γ效价和脾淋巴细胞IL-2的水平。结果显示,球虫感染后第7、14天,添加多糖提取物并疫苗免疫组的血清IFN-γ效价显著高于单纯疫苗组(P<0.01)。然而,单纯提取物添加组与单纯疫苗组之间没有显著差异。3种多糖提取物相比,感染第7天后,AstE组的IFN-γ效价最高,而TreE+V组的IFN-γ的效价显著高于LenE+V组和AstE+V组。脾脏细胞IL-2产量与血清IFN-γ效价的表现基本一致。感染后第7天,提取物加疫苗免疫组的平均IL-2水平显著(P<0.01)高于单纯疫苗组,提取物添加组的平均IL-2水平与单纯疫苗组之间没有显著差异。感染第14天后,多糖提取物添加组及多糖提取物加疫苗组的平均IL-2水平都与单纯疫苗组没有显著差异。IL-2产量在不同多糖提取物添加组间没有显著差异。本实验结果表明,多糖提取物抗球虫作用可能与刺激免疫细胞分泌IFN-γ和IL-2等细胞因子、提高T-细胞免疫应答有关;中药免疫活性多糖对球虫感染鸡有很好的免疫保护作用,当多糖与疫苗一起使用时,效果尤为明显。

The effects of natural immuno-active polysaccharide extracts （E） from two mushrooms, Lentinus edodes （LenE） and Tremellafuciforrnis （TreE）, and an herb, Astragalus rnembranaceus （AstE）, on production of the cytokines IFN-γ and IL-2 were investigated in Eimeria tenella infected chickens. A total of 180 broiler chicken were assigned to nine groups： three groups fed with the extracts （LenE, Tree and AstE）, three groups fed with extracts and immunized with live ooeyst vaccine （LenE ＋ V, Tree ＋ V and AstE ＋ V）, a group immunized with oocyst vaccine, and two controls （With or without E. tenella infected）. Serum IFN-γ titers and IL-2 production of splenocytes were determined at 7 and 14 days post-infection （p. i. ）. The overall mean serum IFN-γ of the groups fed with the extracts and immunized with vaccine was significantly （ P 〈 0.01 ） higher compared with the vaccine group at 7 and 14 days p. i. , whereas that of the groups fed with the extracts only was not significantly different from the vaccine group. Of the three extracts, AstE showed the highest IFN-γ titers at 7 days p. i., and the TreE ＋ V group had significantly higher IFN-γ titers compared with both LenE ＋ V and AstE ＋ V groups. The IL-2 production of splenocytes showed a similar pattern to the serum IFN-y titers. Seven days p. i. , the overall mean IL-2 level of the groups fed with extracts and immunized with vaccine was significantly （P 〈 0.01 ） higher compared with the group immunized with the oocyst vaccine only, but that of the groups fed with the extracts only were not significantly different from the vaccine group. At 14 days p. i., the overall mean IL-2 production of both the groups fed with the extracts and the groups fed with the extracts and immunized with vaccine was not significantly different from the vaccine group. A significant difference in IL-2 production of splenocytes between different extracts was not found. The use of the mushroom and herb polysaccharide extracts might enhance T-cell immune responses, characterized by IFN-γ and IL-2 secretion, against coccidiosis in chickens, and particularly when they are used in conjunction with vaccine. Thus, these immunoactive herbal polysaccharide extracts may enhance protective immunity against infections.