BV-OVA induces CD8 T cell activation.

<p>Splenic CD11c+ cells (2×10⁵) purified from C57BL/6 mice were incubated with BV-WT, BV-OVA or BV-OVAsur at the indicated multiplicity of infection (MOI) for 120 minutes and washed twice. Then, DCs were cultured for 3 days with CFSE-labeled CD8 T cells from OT-I mice (having a transgenic T cell receptor which recognizes OVA_257-264 in the context of H-2K^b). T cell proliferation and CD25 expression were analyzed by flow cytometry, after labeling cells with an anti-CD3 antibody and exclusion of dead cells with 7AAD. (A) A representative dot plot overlay of cell proliferation vs CD25 expression of CD8 T cells cultured with DCs, which were preincubated with BV-OVA (black dots) or BV-WT (gray dots) at a MOI of 30. (B) Percentage of CD8 T cells undergoing one or more rounds of proliferation and (C) IFN-γ content, assessed by ELISA, in supernatants of culture of CD8 T cells with DCs preincubated with BV-OVA or BV-WT. (D) T cell proliferation and (E) CD25 expression of CD8 T cells co-cultured with DCs preincubated with BV-OVA (▪), BV-OVAsur (▴) or BV-WT (○). Results are representative of at least two independent experiments and are expressed as mean +/− SEM (n = 4).