Loss of Wnt4 suppresses post-natal TEC expansion. Flow cytometry analysis of thymi from doxycycline-treated tetO-Cre:ROSA^rtTA/+:Wnt4^fl/fl (Cre⁺) Wnt4-deficient mice and ROSA^rtTA/+:Wnt4^fl/fl (Cre⁻) control littermates. (A) Numbers of EpCAM⁺ cells per thymus. (B) Thymocyte/TEC ratio from the same mice. (C) Analysis of the cortical (CD205⁺Ly51⁺) and the medullary (CD205⁻Ly51⁻) TEC subsets. The graph on the left shows the mTEC/cTEC ratio from Cre⁺ and Cre⁻ mice. Representative FACS data for MHCII and Ly51 staining are shown on the right. The numbers within the FACS plots represent mean percentages of the different epithelial subsets over total EpCAM⁺ cells. The asterisk (bottom right plot) denotes statistical significance for the proportion of cTECs. All histograms represent mean ± SEM from 6-7 mice from at least 4 independent experiments (*P < .05, **P < .01, ***P < .005).