Figure 4.

Immunogenicity of SAM-RVG vaccine delivered by different cationic carriers. Groups of ten BALB/c mice were immunized i.m. on days 0 and 28 with either 1.5 or 0.15 μg of self-amplifying RNA encoding the rabies virus G protein formulated in DOTAP polymeric nanoparticles (NPs), DOTAP Liposomes or DDA Liposomes, and compared to the commercial vaccine Rabipur (1/20 of human dose). GSK trademark CNE56 was used as a positive control. Specific IgG titers were measured by enzyme-linked immunosorbent assay (ELISA). For each group, there were 5 samples, each representing data from pools of two mice (depicted as circles), and the geometric mean titers (GMTs) are solid lines. Sera were collected and analyzed (A) 4 weeks after the first immunization and (B) 2 weeks after the second immunization. Titers < 0.125 EU/mL (dotted blue line) were below the limit of detection, while titers > 0.5 EU/mL (dotted red line) were an indication of protection. Intergroup comparison was analyzed using the one-way analysis of variance (ANOVA) test (Dunnett’s multiple comparison test).