Figure 2. The combination of CpG and R848 enhances splenocyte proliferation and antibody production in pVAX1-Sj26GST–vaccinated mice.

(A) Seven days after the last immunization with pVAX1-Sj26GST alone or with CpG, R848, or both (CpG+R848), splenocytes were harvested and antigen-specific proliferation was measured. Splenocytes (2×10⁵/well) from each mouse were incubated in the presence of SWA (15 µg/mL) or control media for 3 days in a 200 µL volume in 96-well plates. [³H] thymidine (0.5 µCi) was added to each well 16 h before the end of the incubation period. Data are expressed as the mean ± SEM (n = 6 per group) and are representative of 3 independent experiments performed in triplicate wells. * P<0.05. (B) IgG, IgG1, and IgG2a responses in immunized mice. Antibody responses to SWA (15 µg/mL) were determined by ELISA. Data are expressed as the mean ± SEM (n = 6 per group) of 18 mice from 3 independent experiments performed in triplicate wells. * P<0.05; ** P<0.01.