H9N2亚型禽流感嵌合病毒样颗粒的制备

Preparation of chimeric virus-like particles of H9N2 subtype avian influenza

病毒样颗粒(virus-like particle,VLP)疫苗是近年的研究热点。本研究利用昆虫细胞-杆状病毒表达系统,以禽流感病毒的M1蛋白和小鼠白血病病毒的gag蛋白2种不同来源的基质蛋白作为骨架,分别构建了展示G57基因型H9N2亚型禽流感病毒HA蛋白的VLPs。在透射电镜下,所制备的VLP-M1和VLP-gag的形态结构与野生型H9N2亚型禽流感病毒类似,其中以gag蛋白为骨架的VLPs的粒子直径约为150 nm,明显大于VLP-M1粒子。血凝试验结果显示,VLP-gag比VLP-M1提高了1个血凝滴度。Western blot鉴定进一步证实所构建的VLP-M1和VLP-gag中可以同时检测到HA和M1或gag蛋白。由此表明,VLP-gag的表面积大于VLP-M1,其表面镶嵌的HA数量多于VLP-M1。本研究为进一步比较VLP-gag和VLP-M1的免疫原性和免疫保护效果奠定了基础。

Virus-like particle(VLP)is a hot topic in the research field of vaccine in recent years.In this study,the insect cell-baculovirus expression system was used to construct two kinds of virus-like particles(VLPs)exhibiting HA proteins of G57 genotype H9 N2 subtype avian influenza viruses using two different sources of matrix proteins,M1 protein of avian influenza virus and gag protein of mouse leukemia virus,as backbones,respectively.Under the transmission electron microscope,the morphology and structure of VLP-M1 and VLP-gag were similar to those of wild H9 N2 subtype avian influenza virus.The particle diameter of VLPs with the gag protein as skeleton was about 150 nm,which was significantly larger than that of VLP-M1.The results of hemagglutination assay showed that VLP-gag increased an agglutination titer than VLP-M1.The Western blot further confirmed that the HA and M1 or gag proteins could be detected simultaneously in the constructed VLP-M1 and VLP-gag.These results demonstrated that the surface area of VLP-gag was larger than VLP-M1,and the amount of HA embedding on the surface of VLP-gag was more than that of VLP-M1.This study provides a basis for further comparison of the immunogenicity and immunoprotective effects of VLP-gag and VLP-M1.