Canonical early DC progenitors are absent from the adult thymus. (A) BM (upper panel) and thymic (lower panel) cells from CX3CR1^GFP/+ reporter mice were labeled with antibodies against lineage markers (CD19, TCR-β, NK1.1, CD11b, and Gr-1), along with CD11c, MHC-II, and CD135 and analyzed by FACS to detect pre-DCs (CD11c⁺MHC-II⁻). Representative FACS density plots indicate the pre-DC population in the BM and thymus. Numbers next to gates indicate the percentage of cells. (B) Similar to (A), the BM and thymic cells from CX3CR1^GFP/+ reporter mice were stained with lineage markers (CD19, TCR-β, NK1.1, CD11b, CD11c, and Gr-1), as well as Sca-1, CD135, CD117, and CD115 antibodies to visualize MPs (Lin⁻Sca-1⁻CD117^hiCD135⁺CX3CR1⁻), MDPs (CD117^hiCD135⁺CX3CR1⁺), and CDPs (CD117⁺CD135⁺CX3CR1⁺CD115⁺) in the BM (upper panel) and thymus (lower panel). Representative FACS density plots indicate frequencies of MP, MDP, and CDP. Results are representative of 3 independent experiments with at least 3 mice per group.