YTHDF2 regulates cross-presentation capacity of DCs in the context of IR. (A) tSNE map of different clusters of tumor-infiltrating CD45⁺ immune cells in B16F10 tumors as detected by flow cytometry. (B) Populations of infiltrating immune cells in B16F10 tumors assessed by flow cytometry. Macrophages: CD45⁺CD11b⁺F4/80⁺; DCs: CD45⁺CD11c⁺MHC−II⁺Ly6c⁻F4/80⁻; CD8⁺ T: CD45⁺CD3⁺CD8a⁺; CD4⁺ T: CD45⁺CD3⁺CD4⁺. (C) ELISPOT assay of IFN-γ–positive spots secreted by CD8⁺ T cells. WT, Ythdf2-cKO: CD11c⁺ BMDC cocultured with control B16F10-OZ tumor cells; WT+IR, Ythdf2-cKO+IR: CD11c⁺ BMDC cocultured with irradiated B16F10-OZ tumor cells (n = 4, mean ± SEM). (D) MC38 tumor growth in WT or Ythdf2-cKO with or without IR when CD8⁺ T cells were depleted. Anti-CD8 antibody was given at 200 µg/mouse, twice weekly, starting the day before IR (n = 5, mean ± SD). (E) LLC tumor growth in WT or Ythdf2-cKO with or without IR when CD8⁺ T cells were depleted. αCD8 was administered at 200 µg/mouse, twice weekly, starting the day before IR (n = 5, mean ± SD). (F) Size of LLC spontaneous metastasis total area at the end of the study in E, and representative images are shown in Fig. S3 V (n = 5, mean ± SEM). Statistical analysis was performed using two-sided unpaired Student’s t test (C–F); **P < 0.01; ***P < 0.001.