硫酸化黄芪多糖对IBD疫苗接种雏鸡免疫水平的影响

Effects of sulfated astragalus polysaccharides on immune responses of chickens inoculated with IBD vaccine

200只14日龄雏鸡随机均分为9组,6个试验组分别肌肉注射高、低剂量的3种硫酸化黄芪多糖(sAPS)即sAPS40、sAPS50和sAPS60,2个多糖对照组注射高、低剂量的未修饰黄芪多糖(APS),无佐剂对照组注射等量生理盐水,每天1次,连续3 d,第4天用鸡传染性法氏囊病(IBD)疫苗免疫,2周后二免。分别于首次免疫后第7,14,21,28天翼静脉采血,用琼脂扩散法测定血清抗体效价;于首次免疫后第14,21,28和35天心脏采血测定T淋巴细胞增殖。结果表明,3种修饰多糖均能显著提高血清抗体效价,促进T淋巴细胞增殖,作用强于未修饰多糖,且有一定的量效关系,低剂量的效果优于高剂量。综合评价以sAPS60的效果最好,可以作为新型免疫佐剂的候选。

The effects of sulfated astragalus polysaccharides （sAPSs） on immune response in the chickens inoculated with IBD vaccine were investigated. Two hundred 14-day-old chickens were randomly divided into 9 groups. The chickens in six experiment groups were intra- muscularly injected with high and low doses of sAPS40, sAPS50 and sAPS60, respectively, while three control groups, high and low doses of non-modified APS and no adjuvant group （physiological saline） were set. The above groups were treated once a day for three successive days. On days 4 after treatment the chickens were inoculated with infectious bursal disease （IBD） vaccine and re-inoculated after 18 days. On days 7, 14, 21 and 28 after first vaccination, the blood samples were collected from brachial vein for determination of serum antibody by agar diffusion. On days 14, 21,28 and 35 after first vaccination, the blood samples were collected by cardiopuncture for determination of peripheral T lymphocyte proliferation. The results showed that three modified sAPSs could significantly enhance antibody titer and promote lymphocyte proliferation and presented a definite dose-effect relationship. The immune regulations of modified sAPSs were better than those of non-modified APS. In general evaluation, the efficacy of sAPS60 was the best and would be expected as a candidate of new immune adjuvant.