Fig. 1: Functional and state heterogeneity of DC subsets.

A Dendritic cells (DCs) originate from CD34⁺ hematopoietic stem cells (HSCs) and differentiate along distinct lineages into various subsets, including conventional DC1 (cDC1), cDC2, DC3, plasmacytoid DCs (pDCs), monocyte-derived DCs (mo-DCs), and transitional DCs (tDCs). Notably, pDCs can arise from both common myeloid progenitors (CMPs) and common lymphoid progenitors (CLPs), while tDCs, which exhibit features of both cDC2s and pDCs, develop from pre-pDCs. Langerhans cells (LCs), derived from precursor cells that migrate to the epidermis, significantly contribute to sustaining peripheral immune homeostasis. The distinct functional roles of these subsets highlight the extensive heterogeneity within the DC compartment. B In tumors, several mature DC states have been characterized, including mature DCs enriched in immunoregulatory molecules (mregDCs), interferon-stimulated genes (ISGs; ISG⁺ DCs), and CD207⁺ DCs. These states may arise from distinct developmental trajectories. Pre-pDC: pre-plasmacytoid dendritic cell; pre-cDC: pre-conventional dendritic cell; Pro-DC3: Lyz2⁺ DC progenitor; IFN: interferon; TRM: tissue-resident memory T cells; IL4I1: interleukin 4 induced 1; LAMP3: lysosomal associated membrane protein 3; SOCS: suppressor of cytokine signaling; IFIT: interferon-induced protein with tetratricopeptide repeats; USP18: ubiquitin-specific protease 18; FSCN1: fascin actin-bundling protein 1; FCGBP: IgGFc-binding protein. Created with BioRender.com.