Fig. 2.
VMP001-ICMV vaccines elicit robust, durable antibody titers with significantly reduced antigen/adjuvant doses. C57Bl/6 mice were immunized s.c. on day 0 and day 21 with the indicated doses of VMP001 in ICMVs mixed with 25 μg MPLA, or as soluble proteins mixed with either 25 μg MPLA, Montanide ISA-50, or alum. (A) Anti-VMP001 IgG sera titers were assessed over time by ELISA. Anti-VMP001 IgG sera were further characterized on day 90 for (B) IgG1 and (C) IgG2c titers (n.d., not detected). (D) Splenocytes isolated 7 d after priming and boosting with 1 μg VMP001 and 0.1 μg MPLA were stimulated with PBS (white bars) or 2 μg/mL VMP001-ICMVs (black bars) ex vivo, and the cell media were analyzed on day 2 for the concentrations of cytokines. (E) Mice were immunized with titrated amounts of MPLA mixed with 1 μg of VMP001 in either soluble or ICMV formulations. Shown are anti-VMP001 IgG sera titers measured by ELISA on d 50. Data represent the mean ± SEM of two independent experiments with n = 3–4 per group.