Design and functional preliminary investigation of recombinant antigen EgG1Y162–EgG1Y162 against Echinococcus granulosus

In the early stage, our research group cloned Echinococcus granulosus-specific antigen, EgG1Y162, from protoscolex and adult worms of E. granulosus. In order to enhance the immunogenicity of the vaccine, we prepared a recombinant vaccine by tandemly linking EgG1Y162, splicing the protein and linker at the gene level. This approach is expected to improve the immunogenicity of the vaccine by enhancing the molecular weight of the protein and increasing the antigenic epitopes. Bioinformatics was used to predict the physicochemical properties, transmembrane domain, protein structure, and T-/B-cell antigenic epitope of different recombinant proteins, EgG1Y162-linker-EgG1Y162. Finally, the linker sequence, “GGGGSGGG,” which had the least influence on the migration of recombinant protein T/B epitope and can fold normally in series with EgG1Y162, was selected to design the recombinant vaccine. The plasmid was produced using genetic engineering techniques, and the recombinant protein, EGG1Y162-GGGGSGGG-EgG1Y162, was induced to be expressed and purified. EgG1Y162-GGGGSGGG-EgG1Y162 was identified to be correctly expressed with 100% specificity. Compared with EgG1Y162, EgG1Y162-GGGGSGGG-EgG1Y162 was more likely to promote dendritic cell maturation. EgG1Y162-GGGGSGGG-EgG1Y162 was speculated to have the potential to improve antigen immunogenicity by increasing the molecular weight and antigenic epitope.