Conventional dendritic cells (cDCs) are composed of heterogeneous subsets commonly arising from dendritic cell (DC)−committed progenitors. A population of CD301b-expressing DCs has recently been identified in non-lymphoid barrier tissues such as skin. However, whether CD301b + DCs in the skin represent an ontogenetically unique subpopulation of migratory cDCs has not been fully addressed. Here, we demonstrated that CD301b + dermal DCs were distinct subpopulation of FMS-like tyrosine kinase 3 ligand (FLT3L)−dependent CD11b + cDC2 lineage, which required an additional GM-CSF cue for the adequate development. Although the majority of lymphoid-resident cDC2 lacked CD301b expression, dermal migratory cDC2 contained a substantial fraction of CD301b + subset. Similar to CD301b − population, CD301b + dermal DC development was closely regulated by FLT3 signaling, suggesting their common origin from FLT3L-responsive cDC progenitors. However, FLT3L-driven cDC progenitor culture was not sufficient, but additional GM-CSF treatment was required to produce CD301b + cDC2. In vivo development of CD301b + cDC2 was significantly augmented by exogenous GM-CSF, while the repopulation of CD301b + dermal cDC2 was abrogated by GM-CSF neutralization. Functionally, CD301b + cDC2 was capable of producing a high level of IL-23, and the depletion of CD301b + cDC2 effectively prevented IL-17−mediated psoriasiform dermatitis. Therefore, our findings highlight the differentiation program of a distinct CD301b + dermal cDC2 subset in the skin and its involvement in psoriatic inflammation.
Bibliographical noteFunding Information:
This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, funded by the Ministry of Health and Welfare, Korea (HI17C1659 to MGL) and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2017R1D1A1B03035571 to TGK; NRF-2014R1A4A1008625 to CGP).
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Cell Biology