Cell-autonomous regulation of cDC function by MHC-II. (A) Diagram of mixed bone marrow transplantation. A 1:1 mixture of H2-Aacit/cit (CD45.2) or WT (CD45.2) bone marrow cells and congenic WT (CD45.1) bone marrow cells were transferred to lethally irradiated WT (CD45.1) recipients. (B) Representative flow cytometry plots of the indicated cDC populations in spleens of bone marrow chimeric mice. Reduced cDC1 and increased cDC2 frequencies were observed among cDC derived from CD45.2+ H2-Aacit/cit BM (highlighted in red). (C and D) Expression of MHC-I (C) and CD80 (D) on splenic cDC2 from bone marrow chimeric mice. MFI, mean fluorescence intensity. (E) Tumor growth curve of B16F10 melanoma after s.c. inoculation on day 0 into the flank of bone marrow chimeric mice 12 wk after bone marrow transplantation. No PD1 antibody was administered. (F) Body weight relative to weight on the day of bone marrow transplantation (day 0). Data points represent individual mice (C and D). Data are representative of two independent experiments (B–F). WT littermates were used as bone marrow donor controls (B–F). Error bars indicate SD (C, D, and F) or SEM (E). P values were determined by Student’s t test (C and D) or two-way ANOVA with post-hoc Tukey test (E). n = 5 or 6 recipients per group (B–F). *P < 0.05; ****P < 0.0001.