Notch–RBP-J signaling controls the homeostasis of CD8− dendritic cells in the spleen

Signaling through Notch receptors and their transcriptional effector RBP-J is essential for lymphocyte development and function, whereas its role in other immune cell types is unclear. We tested the function of the canonical Notch-RBP-J pathway in dendritic cell (DC) development and maintenance in vivo. Genetic inactivation of RBP-J in the bone marrow did not preclude DC lineage commitment but caused the reduction of splenic DC fraction. The inactivation of RBP-J in DCs using a novel DC-specific deleter strain caused selective loss of the splenic CD8(-) DC subset and reduced the frequency of cytokine-secreting CD8(-) DCs after challenge with Toll-like receptor ligands. In contrast, other splenic DC subsets and…