Fig. 6. Effects on immunogenicity and protective efficacy of tetanus toxin CD4+ T-cell epitope fusion with Qβ-(NANP)3.
Qβ VLPs were chemically coupled with tetanus toxin P2 epitope fused to (NANP)3 (Qβ-tt-(NANP)3) or just to (NANP)3 (Qβ-(NANP)3) and used to vaccinate BALB/c mice (n = 6 per group) by intramuscular injection, using 1 µg per dose, two shots, a 3 week prime-boost interval, with Matrix-M™ adjuvant. A Serum was collected from mice 2 weeks post-boost and standard curve ELISAs performed against (NANP)6. B The avidity index was calculated by taking the ratio of anti-(NANP)6 titres with and without treatment of sera with 7 M urea. Numbers on graphs represent p values from t tests between groups. C Mice were challenged intravenously with 1000 PfCSP transgenic P. berghei sporozoites 3 weeks post-boost. Daily thin blood smears were used to determine the time to reach 1% blood-stage parasitaemia by linear regression. p Value from log-rank test. Means are shown ± SD.