R-eTACs represent a putatievly myeloid population with characteristics distinct from DCs . Related to Fig. 3. (A) Flow cytometry plot showing the gating of R-eTAC1s (EpCAM⁻CCR7⁻) and R-eTAC3s (EpCAM⁺). This gating is from the R-eTAC1/3 shown in Fig. 3 A. (B) Flow cytometry plots showing the gating of R-mDCs (CCR7⁺), R-cDC1s (XCR1⁺SIRPα⁻), and R-cDC2s (XCR1⁻SIRPα⁺) from the R-DC shown in Fig. 3 A. (C) Flow cytometry validation of intracellular Aire staining between WT and germline Aire^−/− mice. (D) Flow cytometry plots of intracellular RORγt staining on the MHCII⁺Aire⁺ cells. (E) Flow cytometry quantification of GFP⁺tdTmt⁺ percentage of parent (left) and absolute counts per mouse (right) from all pooled LNs from RORγt lineage–tracing mice with Aire reporter at various ages, gated on single, live, Lin⁻ cells (n = 3). (F) Quantification of the proliferation of OT-II cells cocultured with R-eTACs (GFP⁺tdTmt⁺) versus DCs (GFP⁻CD11c⁺) in the presence of OVA peptide after 72 h. (G) Experimental setup similar to Fig. 3 H. Quantification of R-eTAC subsets from the Aire⁺MHCII⁺ cells in the Il7r^−/− or WT-derived portions of the BM (n = 5). (H and I) Experimental setup similar to Fig. 3 H, except with Rag2^−/−Il2rg^−/− BM cells instead of Il7r^−/−. Quantification of ILCs (CD90.2⁺CD127⁺), DCs (CD11c⁺MHCII⁺), and R-eTACs (Aire⁺MHCII⁺) (H) and R-eTAC subsets (I) from LNs of Rag2^−/−Il2rg^−/− mixed BMC mice (n = 3). (J) Quantification of DCs, ILCs, and R-eTACs from LNs of neonatal mice gavaged once with PBS or R848 and harvested 24 h later (n = 4 from each group, each dot is pooled from three mice). (K) WT mice were intraperitoneally treated with either isotype (Iso) or recombinant Flt3L (rFlt3L) for 7 days. DCs and R-eTACs were quantified from LNs (n = 10 from each group). (L) WT mice were intraperitoneally treated with either isotype (Iso) or anti-Flt3L antibody (αFlt3L) for 7 days. DCs and R-eTACs were quantified from the spleen (n = 20 from each group). (M) Flow cytometry quantification of DC subsets and R-eTACs from Clec9a^CreER×Rosa26-LSL-tdTmt mice LNs (n = 6). Mice were put on tamoxifen chow for 1 wk to induce labeling. (N) Flow cytometry quantification of monocytes, R-eTACs, DCs, and B cells from Ms4a3^Cre×Rosa26-LSL-tdTmt mouse LNs (n = 10). Data in E are from one independent experiments. Data in F–I are representative of at least three independent experiments. Data in J–N are pooled from two to three independent experiments. Error bars: mean ± SEM; statistics were calculated by one-way ANOVA with Tukey’s multiple comparisons test (F) or unpaired two-sided t test (G–I, K, and L); ***P < 0.0005, ****P < 0.0001.