ChIL-2对H5亚型AIV疫苗免疫增强作用研究

鸡白细胞介素2真核表达质粒pCI-IL-2及原核表达重组鸡白细胞介素2(rChIL-2)分别与H5亚型禽流感油乳剂灭活苗联合使用,25日龄首免,40日龄时加强免疫.MTT法检测各组鸡外周血淋巴T细胞增殖,HI试验监测H5亚型禽流感抗体水平的消长规律,结果表明:pCI-IL-2及rChIL-2均能显著增强AIV疫苗的免疫效果(P＜0.05),pCI-IL-2和rChIL-2两组间差异不显著(P＞0.05);证实鸡白细胞介素2对H 5亚型禽流感疫苗有免疫增强作用.rChIL-2协同免疫组MTT及HI试验均在第四周 达到峰值,pCI-IL-2协同免役组峰值出现时间稍晚,但随后质粒免疫组可维持在更高的水平值.提示IL-2蛋白的作用更迅速,IL-2质粒作用更持久.

Enhancement effects of chicken interleukin-2 on immune responses of H5 subtype avian influenza virus vaccines

In order to boost immune response of conventional vaccines,investigation was made on immunoadjuvants-eukaryotic expression plasmid(pCI-IL-2) and recombinant chicken IL-2(rChIL-2) expressed in E.coli.The adjuvants were coadministrated with H_5 subtype inactivated avian influenza virus(AIV) vaccines.Non-immunized commercial chickens were injected initially at 25-day-old and boosted 2 weeks later.Proliferation responses of chicken periphery blood lymphocytes were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenylt-etrazolium bromide(MTT) assay and the titers of specific antibodies to the H_5 vaccine by hemagglutinin inhibit(HI) test.As the results revealed,the cellular and humoral immune responses were significantly enhanced in the groups co-immunized with pCI-IL-2 or rChIL-2 compared to the group inoculated with H_5 vaccine only.No significant difference were found between the two co-immunized groups(P<0.05).Peak values of MTT and HI in the rChIL-2 co-inoculated group were attained 4 weeks after initial inoculation,which was earlier than the group co-inoculated with pCI-IL-2.These results presented evidence that both pCI-IL-2 and rChIL-2 could be employed as effective immunoadjuvant to conventional vaccines against avian influenza.