Figure 2.

IFNβ-mediated expansion of gB-specific CD8⁺ T cells is dependent on XCR1⁺ DCs, CD4⁺ T cells and CD40/CD40L signalling. Expansion of 5 x 10⁴ transferred naïve gBT.I (A, B, D) or endogenous gB-specific CD8⁺ T cells (C) was measured seven days post-vaccination with 2.5 x 10⁶ irradiated B16.Kb^loss.gB ± IFNβ cells. (A) XCR1-DTR mice received either PBS control or 25 ng/g weight diphtheria toxin (DTx) one day prior to vaccination to deplete XCR1⁺ DCs (n = 8 per group). (B) C57BL/6 mice received control PBS or 200 µg anti-NK1.1 one day prior and post vaccination (n = 7-9 per group). (C) Splenocytes from IFNβ-vaccinated IA/E^o/o mice were restimulated with gB peptide and IFNγ ⁺ endogenous CD8⁺ T cells were measured (n = 9-11 per group). (D) C57BL/6 mice received control isotype or 200 µg anti-CD40L on the same day as vaccination (n = 6-8 per group). Data is pooled from two independent repeats and analysed by one-way (C) or two-way (A, B, D) ANOVA, ****p < 0.001, ***p < 0.005, *p < 0.05, ns, not significant. Bars represent mean ± SEM.