Fig. 7: Splenic infections produce type I IFNs and contribute to VSV^∆M51-induced antitumour immunity.

a Ex vivo image of spleen 6 h post VSV^∆M51-GFP, representative of n = 6 mice imaged over 2 independent experiments. Scale bars are 200 µm. b Virus titers in spleen or serum at indicated time points post VSV^∆M51-GFP (n = 3 mice/group.) c Levels of TNF and IFNs in serum 6 h after mice received PBS or VSV^∆M51-GFP, followed by sham or splenectomy surgery (n = 4 mice/group (ctl PBS, ctl VSV), n = 5 mice/group (splen. VSV), n = 6 mice/group (sham PBS, sham VSV, splen. PBS), compiled from 2 independent experiments, multiple two-tailed, unpaired t tests between sham VSV and splen. VSV groups, with Holm-Sidak post-test). d Schematic of FITC painting technique with PBS (P) or VSV^∆M51 (V) treatment followed by sham or splenectomy surgeries. e, f Frequency (e) or expression of CD80 and CD86 (f) on FITC⁺ DCs (left) and FITC⁺CD103⁺ DCs (right) in the iLN of mice treated as in d (n = 4 mice/group (control P, control V), n = 7 mice/group (sham P), n = 8 mice/group (sham V, splen. P, splen. V), where the same samples were used to measure both FITC⁺CD11c⁺ DCs and FITC⁺CD103⁺ DCs, compiled from 2 independent experiments, one-way ANOVA with Tukey’s post-test). g Schematic to determine the contribution of splenic infections to tumour regression. h Tumour growth (left) and overall survival (right) of M3-9-M^Res1-bearing mice treated with PBS or VSV^∆M51, followed by no surgery (top), sham surgery (middle) or splenectomy surgery (bottom) (left: n = 5 mice/group except n = 6 mice/group (no surgery VSV), representative of 2 independent experiments; right: n = 10 mice/group (no surgery PBS, sham surgery PBS, splenectomy surgery PBS, splenectomy surgery VSV), n = 11 mice/group (sham surgery VSV), n = 12 mice/group (no surgery VSV), compiled from 2 independent experiments, log-rank Mantel-Cox test). In all experiment, VSV^∆M51 was delivered i.v. at 5 × 10⁸ PFU. Points/bars at mean ± SD. Schematics in d and g were created in BioRender. Lab, M (2024) BioRender.com/m62j741. Source data are provided as a Source Data file. Occasionally n is given as a range as the number of mice in each group varies. Please see the Source Data file for the exact n in each group.