(a) Mouse models of CAT with confined expression of TdTOM to distinct TEC subsets. (b) Representative flow cytometry plots showing the frequency of TdTOM+ cells among MACS-enriched CD45–EpCAM+ cells isolated from Foxn1CreRosa26TdTOM (Foxn1Cre), CsnbCreRosa26TdTOM (CsnbCre), and Defa6iCreRosa26TdTOM (Defa6iCre) mice. (c) Quantification of TdTOM+ cells from Figure 1b (mean ± SEM, n = 7–12 mice from three independent experiments). (d) Microscopy images of thymic sections from Foxn1Cre, CsnbCre, Defa6iCre, and Cre– control mice depicting the levels of TdTOM expression and its restriction to keratin 14+ areas demarcating thymic medulla. Yellow dashed lines denote the zones that are shown in higher magnification. Scale bars and color code are provided. (e) Quantification of the absolute numbers of CD45–EpCAM+TdTOM+ cells isolated from Foxn1Cre, CsnbCre, and Defa6iCre thymi counted by flow cytometry. (f) Representative flow cytometry plots of different TEC subsets in Foxn1Cre, CsnbCre, and Defa6iCre mice. (g) Quantification of the ratios of the frequencies of TEC subsets within CD45–EpCAM+TdTOM+ cells to the frequencies of TEC subsets within CD45–EpCAM+ cells in Foxn1Cre, CsnbCre, and Defa6iCre mice (mean ± SEM, n = 7–8 mice from three independent experiments). The ratios were calculated using percentages in Figure 1—figure supplement 1c. Statistical analysis in (g) was performed using one-way ANOVA with Bonferroni´s multiple comparison test, *p≤0.05, **p≤0.01, ***p≤0.001, ****p<0.0001, ns, not significant.