Transitional dendritic cells are distinct from conventional DC2 precursors and mediate proinflammatory antiviral responses

Cross-species analyses reveal RORγt-expressing dendritic cells are a lineage of antigen presenting cells conserved across tissues

“…Their functional versatility makes them attractive for being targeted in vaccination against pathogens or cancer (2-6). Accordingly, considerable work has been invested in understanding the functional and ontogenetic diversity of cDCs, yet these cells remain ambiguous to define as fate mapping has recently uncovered novel populations with overlapping phenotype but distinct origin (2,(7)(8)(9)(10)(11)(12). cDCs are generally considered to descend from committed myeloid cDC progenitors (13)(14)(15) and exist as functionally specialized subtypes.…”

“…Both subtypes can induce Th17 responses but cDC2A appear more potent inducers of T follicular helper cell (Tfh) responses (19), while cDC2B may better promote Th2 responses (20). Fetal liver lymphoid progenitors in neonatal spleen and lymphoid derived transitional DCs (tDCs) in adult spleen can differentiate into cells resembling cDC2A and cDC2B (9)(10)(11)21). tDCs are cells with features of both cDCs and plasmacytoid DCs (pDCs), the latter of which are potent producers of type I interferons in response to viruses (9,10,21).…”

“…Fetal liver lymphoid progenitors in neonatal spleen and lymphoid derived transitional DCs (tDCs) in adult spleen can differentiate into cells resembling cDC2A and cDC2B (9)(10)(11)21). tDCs are cells with features of both cDCs and plasmacytoid DCs (pDCs), the latter of which are potent producers of type I interferons in response to viruses (9,10,21). Monocytic progenitors also generate cDC2B-like cells, which have been termed DC3 because of their distinct origin and similarity to human DC3 populations and in vitro appear superior in polarizing IL17A producing Th17 cells to cDC2B (12,22,23).…”