DPP4 and neoplasm: reported that tumor cell‐derived IFN‐I can activate MHC class I‐dressed CD11b+ cDCs to promote protective anti‐tumor CD8+ T cell immunity, and they named this DC subset as ISG+ DC.[46] In addition to promoting anti‐tumor immunity, IFN‐I induces a new DC subset called ifn‐cDC2 (CD11c+CD11b+CD26+CD64midMAR‐1+), which acquires features of cDC1s and macrophages to orchestrate immunity against respiratory virus infection.[28] Similarly, we also found ME49Δompdc/gra4 immunization can expand the population of CD64+MAR‐1+CD11b+ DCs in an IFN‐I‐dependent manner.