a Treatment schedule used in (b–d). All mice were bearing SC B16F10-Ova tumors. b IFNγ ELISPOT analysis of splenocytes from mice immunized with Ad-DCT or Ad or polyI:C co-administered with DCT peptide (all IM) (from left to right; n = 4, 5, 5, and 3); c MRB-DCT, MRB co-administered with DCT peptide (left panel) or MRB-Ova or MRB co-administered with Ova peptide (right panel) (all IV) (from left to right; n = 4, 5, 3, 3, 3, 5 and 4) or; d MRB, VSV or VV co-administered with DCT peptide (all IV) (from left to right; n = 2, 5, 5 and 5). For b–d, the statistical analyses refer to the comparison between the corresponding ex-vivo “No restim” and “restim” conditions. NS: p > 0.05, *: p < 0.05, **: p < 0.01, ***: p < 0.001 (unpaired two-tailed t-test). e Biodistribution analysis of C57BL/6 mice injected IV with MRB-Ova with or without co-administration of Ova peptide for 24 h (n = 3). f Flow cytometry analysis of GFP+ splenocytes from mice injected with MRB-GFP with or without Ova peptide. The spleens were collected 1.5 h post-injection, dissociated and cultured ex-vivo for 4.5 h prior to staining and analysis. The graph shows the percentage of live B cells (CD19+, B220+) that are GFP+ (n = 3). g Flow cytometry analysis of GFP+, B220+, CD19+ cells from (f) (n = 3). The contour plots show the gating strategy to distinguish different subsets of B cells and the right graph shows the quantification of the marginal zone (MZ), follicular (FO) and other B cell populations. NS: p > 0.05 (unpaired two-tailed t-test). Source data are provided as a Source Data file. Exact p values can be found in the Source Data.