Effect of IL-2 co-expressed or co-inoculated with immuno-dominant epitopes from VP1 protein of FMD virus on immune responses in BALB/c mice

Abstract

based on immuno-dominant epitopes have been shown to induce immune responses. Furthermore, for safety of immunization, access to efficient adjuvants against FMD virus seems to be critical. Materials and Methods: In this study, we produced epitope recombinant vaccines from the VP1 protein of the FMD virus for serotype O of Iran. Constructs were included polytope (tandem-repeat multipleepitope), polytope coupled with interleukin-2 (polytope-IL 2) as a molecular adjuvant and IL-2. Three expression vectors were constructed and expressed in Escherichia coli BL21 (DE3). To evaluate whether these recombinant vaccines induce immune responses, BALB/c mice were injected with the recombinant vaccines and their immune responses were compared with a negative control group. The humoral and cellular immune responses were measured by ELISA. Results: The results showed that IL-2 co-expressed or co-inoculated with Polytope protein enhances the immune effect of multiple epitope recombinant vaccine against FMD virus. The results of total immunoglobulin G (IgG), IgG1, and IgG2a levels and secretion of interferon gamma (IFN-γ), IL-4 and IL-10 revealed that there were significant differences between negative control group and other injected mice with the recombinant vaccines (P<0.05). Conclusion: Observations indicated that the epitope recombinant plasmid of the VP1 protein coexpressed or co-inoculated