Fig. 3. Effects on immunogenicity and protective efficacy of combining Qβ-(NANP)6 and Qβ-(ADGN long) vaccines.
BALB/c mice (n = 6 per group) were vaccinated with two shots by intramuscular injection of 1 µg of each Qβ-peptide in Matrix-M™ adjuvant into separate legs using a 3-week prime-boost interval. A Standard curve ELISAs from sera taken 2 weeks post-boost, and avidity. Numbers represent p values from ANOVA with Bonferroni’s multiple comparisons test. B Mice were challenged 3 weeks post-boost by intravenous injection of 1000 PfCSP replacement P. berghei sporozoites into the tail vein. The time to reach 1% blood-stage parasitaemia was calculated by linear regression from daily thin blood smears. Numbers represent p-values from log-rank tests between indicated groups. Means are shown ± SD. C Reduction in liver load, the ratio of infected hepatocytes in vaccinated (LV) compared to naïve mice (LN), was calculated using the formula Reduction (%) = (1 − iV)*100, where the vaccine-reduced infectivity iV = LV/LN = gTn−Tv, where g is the blood-stage growth rate, TN the median time-to-1% in naïve mice, and TV the time-to-1% in vaccinated mice.