Figure 5.

Deletion of CD122-deficient CD4SP CCR7+ Helios+ cells is Foxp3 independent. CD45.1+ mice were irradiated and reconstituted with cell mixtures containing CD45.1+ wild-type BM plus CD45.2+ BM from wild-type, Foxp3^null/y, Il2rb^–/– or Il2rb^–/– Foxp3^null/y siblings. Chimeric mice were examined 6–7 weeks later, 7 days after a single EdU injection. (a) Gating strategy to analyse nascent cells derived from thymocytes that were proliferating 7 days prior to analysis. Left plots show side-scattered light (SSC) versus EdU on all thymocytes, with a gate for EdU+ events that was empty in the uninjected control. The CCR7+ subset of EdU+ cells was analysed for CD4/CD8, and the CD4SP subset was then analysed for expression of CD45.1 versus CD45.2. (b) Plots show Helios/CTLA-4 phenotype of EdU+ CCR7+ CD4SP CD45.2+ cells. Graphs show the frequencies of Helios+ events (top) or the CTLA-4 MFI of Helios+ events (bottom) as gated in the plots. We generated nine chimeras per group, except for the group bearing wild-type BM cells, which contained 10 mice. Possibly due to intraperitoneal injection failure, EdU+ cells were not detected in thymus samples from some EdU-injected mice; these samples were excluded from the analysis. Graphs show data compiled from two independent experiments with each symbol representing one mouse. Unpaired two-tailed Student's t-tests P-value symbols: ** 0.001–0.01, *** 0.0001–0.001; **** <0.0001