Figure 5.

Virus replicon particle (VRP) and polyplex induce a specific CD8⁺ T cell immune response against influenza antigens. Induction of CD8⁺ T cell immune responses against the RepRNA encoded CSFV E2 and influenza virus HA and NP, determined by restimulation of freshly isolated PBMCs and cells derived from draining LNs (day 56 post-first immunization); cells were restimulated with recombinant E2 (1 µg/ml), HA (1 µg/ml) or NP (1 µg/ml), or non-stimulated (-). (A) After 5 days of cell culture, the numbers of division cycles (D0-D7) of proliferating CD8⁺ T cells in PBMC and draining LN compartments, were determined by flow cytometry using the FlowJo software. The values represent the mean of proliferating CD8⁺ T cells of the five individual pigs for each group. Numbers in red represent the mean percentage of highly proliferative cells (≥ 5 division cycles). (B) After 5 days of cell culture, representative dot plots are shown for draining LN compartments of three immunized animals per group for proliferating CD8⁺ T cells.