Extended Data Figure 5. Characterization of Tbx21^RFP-CreFoxp3^FL mice.

a, Targeting strategy for the Tbx21 locus (above) and RFP expression in the indicated cell populations in spleens of homozygous Tbx21^RFP-Cre mice (below). b, Progressive loss of hair pigmentation in Tbx21^RFP-CreFoxp3^FL mice. c, (Above) RFP and YFP expression and (below) CD44 and CD62L expression in the indicated splenic cell populations in Tbx21^RFP-CreR26Y mice. d, Activation and expansion of RFP⁺ T cells in lymph nodes (above) and lungs (below) of the indicated mice. e, Cytokine production by CD4⁺Foxp3⁻ and CD8⁺ T cells in lungs of the indicated mice. f, Characterization of lymph node Treg cells. g, Percentages of ex-Treg cells in spleens, lymph nodes, and lungs. h, (Above) flow cytometry of lymph node CD4 T cells, as quantified in (g); numbers indicate the percent Foxp3⁻CD25⁺; (below), histograms showing expression of Treg cell signature molecules in CD4⁺Foxp3⁻CD25⁺ cells in lymph nodes of Tbx21^RFP-CreFoxp3^WT (open gray histogram), Tbx21^RFP-CreFoxp3^FL (open red histogram), Tbx21^RFP-CreFoxp3^WT/WT (open blue histogram), and Tbx21^RFP-CreFoxp3^FL/WT (open black histogram) mice. CD4⁺Foxp3⁺CD25⁺ cells from a Tbx21^RFP-CreFoxp3^WT (shaded gray histogram) mouse are shown as a point of reference. Bars, mean±s.e.m. Two-tailed t test (***, **, and * denotes p values <0.001, 0.01, and 0.05, respectively; NS – not significant). Data represent the combined results from several experiments.