Fig. 2.

i.m. Injection of Balb/c mice with ALVAC induces circulatory IFN-α and IFN-γ. (A) At time 0, groups of mice (5–6 per group) were immunised i.p. with 10 μg of a biotinylated anti-IFN-γ-mAb (no azide/low endotoxin) followed by i.m. immunisation of either placebo or ALVAC at 1/10 human dose. At various time points serum samples were prepared from these mice and frozen at −20 °C until analysis. Levels of the complex of mAb + IFNγ were determined by an ELISA using a standard curve generated using recombinant IFN-γ that had been pre-incubated with biotinylated mAb. Results are expresses as mean cytokine concentration ± standard deviation. ^*p < 0.05, ^***p < 0.001 and ns = not significant. (B) In a separate experiment groups of Balb/c mice (5 per group) were immunised with Placebo or ALVAC (1/10 human dose) at time 0. Serum samples were removed at various time-points and frozen at −20 °C until analysis. Levels of serum IFN-α were determined by ELISA in triplicate on serum pools from each group. Results are expressed as the mean cytokine concentration ± standard error.