Dendritic cells (DC) are antigen presenting cells controlling T cell activation. In human, the diversity, ontogeny and functional capabilities of DC subsets are not fully understood. Here, we identified circulating CD88-CD1c+CD163+ DC (termed as DC3) as an immediate precursor of inflammatory CD88-CD14+CD1c+CD163+FcRI+ DC. DC3 develop via a specific pathway activated by GM-CSF, independent from the cDC-restricted (CDP) and monocyte-restricted (cMoP) progenitors. As classical DC, but unlike monocytes, DC3 drove the activation of nave T cells. In vitro, DC3 displayed a distinctive ability to prime CD8+ T cells expressing a tissue-homing signature and the epithelial homing alpha-E integrin (CD103) through transforming growth factor-b (TGF-) signaling. In vivo, DC3 infiltrated luminal breast cancer primary tumors and DC3 infiltration correlated positively with CD8+CD103+CD69+ tissue-resident memory T cells. Altogether, these findings define DC3 as a lineage of inflammatory DC endowed with a strong potential to regulate tumor immunity. SOURCE: Kristine Vaivode (kristine.vaivode@kcl.ac.uk) - Dr Pierre Guermonprez lab King's College London

Pluto Bioinformatics

GSE151072: Transcriptional and functional analysis of CD1c+ human dendritic cells identifies a CD163+ subset priming CD8+CD103+ T cells [Breast_iLN]