鸡白细胞介素-18对H_9亚型禽流感灭活油乳苗的免疫增强作用

Immune Enhancement Effects of Chicken Interleukin-18 on Inactivated Oil Emulsion Vaccine of H_9 Subtype Avian Influenza

[目的]探索鸡白细胞介素-18(IL-18)在H9禽流感(AI)灭活油乳苗免疫中的免疫佐剂作用。[方法]从鸡脾淋巴细胞中克隆鸡IL-18基因,亚克隆到真核表达载体pcDNA3.1(+)中,构建真核表达质粒pIL-18。将重组真核表达质粒pIL-18、H9亚型AI灭活油乳苗及其二者联合分别免疫14日龄SPF鸡,检测其细胞免疫和体液免疫水平,评价鸡IL-18在H9亚型禽流感灭活油乳苗中的免疫增强作用。[结果]成功克隆了鸡IL-18全基因,大小为597 bp。质粒pIL-18和H9亚型AI灭活油乳苗联合免疫的SPF鸡所产生的HI抗体效价在接种第4周后明显高于H9亚型AI灭活油乳苗免疫组;其T淋巴细胞的增殖反应也强于H9亚型AI灭活油乳苗免疫组。[结论]质粒pIL-18能提高H9亚型禽流感灭活油乳苗诱发的免疫应答,为研究防制禽流感的新型疫苗提供了新思路。

[ Objective ] The research aimed to explore the immune adjuvant effect of interleukin - 18 （ IL-18 ） in the immunization of inactivated oil emulsion vaccine of H9 subtype avian influenza. [ Method] Chicken IL-18 gene was amplified from total RNA extracted from chicken spleen lymphocytes. PCR product was inserted into eukaryotic expression vector pcDNA3.1 （ ＋ ） to construct eukaryotic expression vector pIL-18. The recombinant eukaryotic expression vector pIL-18, inactivated oil emulsion vaccine of H9 subtype avian influenza and the mixture were used to im- munize 14 - day - old SPF chicken and detect its cellular immunity and humoral immunity levels. The immune enhancement effects of chicken on inactivated oil emulsion vaccine of H9 subtype avian influenza were evaluated. [ Result] Total IL-18 gene of chicken was successfully cloned, and its length was 597 bp. The titers of HI antibody produced in SPF chicken immunized with plasmid pIL-18 and inactivated oil emulsion vaccine of H9 subtype avian influenza in the four weeks after inoculation were obviously higher than that in inactivated oil emulsion vaccine of H9 subtype a- vian influenza. Its multiplication response of T lymphocyte was stronger than that in inactivated oil emulsion vaccine of H9 subtype avian influenza group. [ Conclusion] Plasmid pIL-18 could enhance the immune response induced by inactivated oil emulsion vaccine of H9 subtype avian influ- enza, which provided a new thought for studying and developing new vaccines of avian influenza.