*3.5. Antigen-Specific Cellular Immune Responses in Vaccinated Mice*

ELISpot assays were used to evaluate the antigen-specific cellular immune response in vaccinated mice. Since 20 μg VLPs-only did not stimulate the production of specific antibodies and neutralizing antibodies, the VLPs-only group was removed in the cellular immune response experiment. The results from the IL-4 ELISpot assay are shown in Figure 5A. The SFCs produced from the splenocytes of mice immunized with 20 μg SUDV VLPs mixed with an ISA 201 adjuvant were significantly higher compared with mice immunized with PBS or ISA 201. The immunization with 20 μg SUDV VLPs mixed with an ISA 201 adjuvant also resulted in increased IFN-γ responses, with SFCs production that were significantly higher than that following immunization with PBS or ISA 201 (Figure 5B). These results demonstrate that 20 μg SUDV VLPs mixed with an ISA 201 adjuvant enhances IL-4 and IFN-γ responses in mice.

**Figure 5.** IFN-γ and IL-4 secretion by proliferating splenic induced by a purified baculovirus-expressed SUDV GP protein. Splenocytes from immunized mice and were stimulated with purified -prokaryotic expressed SUDV GP (10 μg/mL) for 48 h, and the level of IL-4 (**A**) or IFN-γ (**B**) were quantitated using an ELISpot assay. The data represent the mean ± standard deviation (SD) of SFCs per million cells. Statistical analysis between the two groups was analyzed by using Tukey's multiple comparison test (\* *p* < 0.05, \*\* *p* < 0.01).
