Table 1.

Major subsets of DCs in humans and mice^*

DC subset	Phenotype		Specific transcription factors	Specific mediators produced upon activation	Specific antigen- presentation capacities	Location	Tissue condition
	Mice	Humans
Plasmacytoid DC	CD11cint MHC class IIint B220, BST2 and SIGLEC-H	CD11c− MHC class IIint CD123, BDCA2 and BDCA4	TCF4 (also known as E2-2)	Type 1 IFN	Present and Cross-present peptides only after activation	Lymphoid organs	Steady state
CD11b+ESAMhi cDC	CD11chi, MHC class IIhi, CD11b, CX3CR1low and ESAMhi	CD11chi MHC class IIhi CD11b and BDCA1	Notch 2	ND	Present peptides on MHC class II molecules to CD4+ T cells	Lymphoid organs	Steady state
CD11b+ESAMlow cDC‡	CD11chi, MHC class IIhi, CD11b, CX3CR1hi and ESAMlow	CD11chi, MHC class IIhi, CD11b, CD16 and CD14	ND	TNF and IL-12	ND	Lymphoid organs	Steady state
CD8α+ cDC	CD11chi, MHC class IIhi, XCR1, CLEC9A and CD8α	CD11cint MHC class IIhi XCR1, CLEC9A and BDCA3	BATF3	IL-12	Cross-present peptides on MHC class I molecules to CD8+ T cells	Lymphoid organs	Steady state
CD103+ cDC	CD11chi, MHC class IIhi, CD103, XCR1 and CLEC9A	CD11chi MHC class IIhi XCR1, CLEC9A and BDCA3	BATF3	ND	Cross-present peptides on MHC class I molecules to CD8+ T cells	Peripheral tissues	Steady state
CD11b+ cDC	CD11chi MHC class IIhi CD103§, CD11b and CD24	CD11chi, MHC class IIhi, CD11b, SIRPα§ and BDCA1║	IRF4 and Notch 2❡	IL-6 and IL-23	Present peptides on MHC class II molecules to CD4+ T cells	Lungs and gut	Steady state
Interstitial cDC	CD11chi, MHC class IIhi, X3CR1 and CD11b	CD11chi, MHC class IIhi, CD11b, CD16 and CD14	ND	TNF and IL-12	ND	Peripheral tissues	Steady state
Langerhans cell	CD11chi MHC class IIhi Langerin and CD205	CD11chi MHC class IIhi CD1a, Langerin and CD205	ND	ND	ND	Epidermis	Steady state
Monocyte-derived DC	CD11chi, MHC class IIhi, CD11b, CX3CR1 and CD209	CD11chi MHC class IIhi and CD11b	ND	TNF and iNOS	Present peptides on MHC class II molecules to CD4+ T cells	Inflamed lymph nodes and tissues	Inflamed

BATF3, basic leucine zipper transcription factor ATF-like 3; BDCA, blood dendritic cell antigen; BST2, bone marrow stromal antigen 2; cDC, classical dendritic cell; CLEC9A, C-type lectin domain family 9 member A; CX₃CR1, CX₃C-chemokine receptor 1; ESAM, endothelial cell-selective adhesion molecule; IFN, interferon; IL-12, interleukin-12; iNOS, inducible nitric oxide synthase; IRF4, interferon-regulatory factor 4; ND, not described; SIGLEC, salic acid-binding immunoglobulin-like lectin; SIRPα, signal-regulatory protein-α; TCF4, transcription factor 4; TNF, tumour necrosis factor; XCR1, XC-chemokine receptor 1.

^*The table (which is by no means all-inclusive) shows the main cell surface markers, subset-specific transcription factors and predominant functional features of the putative orthologous human and mouse dendritic cell subsets^{3–5,116,117}.

^‡It is unclear whether the human and mouse subsets of these DCs are orthologous.

^§Expression has been reported in the gut.

^║Expression has been reported in the lungs.

^❡The expression of Notch 2 is ubiquitous; however, its function is only required in this DC subset in the gut and not in the lungs.