Figure 1. Stable T-bet expression in a subset of peripheral Treg cells.

a, Splenic cells inTbx21^RFP-CreERT2 mice 3 weeks following tamoxifen (tx) gavage on days −2 and 0. Numbers on graph (right) indicate the mean. b, Schematic of tx administration to Tbx21^RFP-CreERT2 mice (above) and flow cytometry (below) of splenic CD4 Thy1.1⁺ and Thy1.1⁻ cells. c, (Above) RFP⁺ (left axis, squares) and YFP⁺ (right axis, circles) Treg cells; (below) Percent RFP⁺ of YFP⁺Treg cells 3 weeks (white symbols), 3 months (gray symbols), and 7 months (black symbols) post tx gavage. d, (Above) schematic of tx treatment with Nippostrongylus brasiliensis (Nb) infection; (below, left) percent RFP⁺ among YFP⁺ Treg cells in PBS- (white circles) and Nb- (black circles) challenged mice; (below, right) RFP expression in Treg (shaded histograms) or YFP⁺ Treg (open histograms) cells from spleens of PBS- (black) or Nb- (red) challenged mice. Bars, mean±s.e.m. Two-tailed t test (NS – not significant). All data are representative of 2 experiments, n ≥ 3 mice per group each.