Fig. 6.

IFN-γ production assessed by intracellular flow cytometry in response to in vitro restimulation with FMDV vaccine antigen. Post-vaccination with O1 Manisa FMD commercial vaccine, PBMC (panel 1, 14 weeks post-vaccination) and purified CD4⁺ T-cells+APCs (panel 2, 24 weeks post-vaccination) were cultured in vitro for 24 (a and b), 48 (c and d), 72 (e and f) and 96 (g and h) h in the presence of medium+IL-12 (a, c, e and g) or optimal concentrations of inactivated O1 Manisa FMDV vaccine antigen (FMDV)+IL-12 (b, d, f and h). At the end of the culture period, the cells were permeabilized, stained intracellularly with either a mouse anti-bovine IFN-γ (cc302) or isotype-matched control mAb (TRT 1, data not shown) followed by incubation with FITC-conjugated goat anti-mouse IgG1 antibody (IgG1 FITC), and analysed by flow cytometry. The percentages of cells in each quadrant are illustrated. [Cells were only stained with FITC-labelled antibodies, the negative FL4-H fluorescence channel (y-axis) was only used for the purpose of creating the dot plots]. One representative dataset (animal FMD 7) from five (panel 1) and two (panel 2) different animals is shown.