Fig 5. Seroconversion and protection against challenge induced by VLPs.

Transgenic mice expressing the human poliovirus receptor were immunised intraperitoneally once or twice (x2) with PBS or 0.5 human dose equivalents of IPV or VLPs (A, B—type 1; C, D—type 2; E, F—type 3) then challenged intramuscularly with 25 PD₅₀ of homologous wild type virus. Graphs A, C & E show neutralising antibody titres against homologous serotype viruses in blood samples taken the day prior to challenge. Graphs B, D & F show survival rates following challenge with (B) type 1 Mahoney, (D) type 2 MEF-1 and (F) type 3 Saukett. Bars (A, C & E) indicate 95% CI of the geometric mean titre.