Fig. 10. Draining lymph node irradiation disrupts the CCR7-CCL19/CCL21 axis, which correlates with a reduction in the lymph node-infiltrating cross-presenting conventional type 1 dendritic cells.

A All B16F10-Luc tumor-bearing mice received α-CTLA-4. “TM IR + ICI” group (blue) received tumor IR, “TM + C-DLN IR + ICI” group (orange) received DLN IR concomitantly to the tumor IR, and “TM + NEO-DLN IR + ICI” group (purple) received DLN IR 7 days prior to tumor IR. Dendritic cells were analyzed at different timepoints (indicated by arrows). Gating strategy is shown in Supplementary Fig. 7. CCL19 and CCL21 protein quantification was performed on day 2 after tumor IR (arrowhead). B CCL19 and CCL21 protein concentration in the DLNs on day 2 after tumor IR (corresponding to day 9 after neoadjuvant DLN IR), expressed relative to the average value of the sham-irradiated mice. n = 4 mice per group. C, D cDC1s in the DLN displayed as cell counts (C, left) and as a percentage of all cDCs (C, right). D Representative plots from DLNs on day 4 after tumor IR. Numbers indicate the percentage of cDC1 within the cDC compartment. n ≥ 4 mice per group (exact numbers provided in Source Data file). Each dot represents an individual mouse. Floating bars span from the minimal to the maximal value of each group. Line indicates the mean. Data were tested for normality using the Shapiro–Wilk test. All data followed a normal distribution. Treatment groups were compared using the two-sided unpaired t test (C, day -3 and day 0) and one-way ANOVA with Holm–Sidak’s multiple comparisons test (B and C, day 4). All p values are displayed, with *, ** and *** indicating p < 0.05, p < 0.01 and p < 0.001, respectively. Figure A, created with BioRender.com, released under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International license.