Figure 2.

CTLA-4 upregulation in CD4SP CCR7+ Helios+ cells is Foxp3 independent. (a) Gating strategy used to distinguish three subsets within the CCR7+ CD4SP thymocyte population based on Helios/Foxp3 phenotype, and CTLA-4 expression on these three subsets. (b) Helios/CTLA-4 phenotype (upper panel) and Helios/Foxp3 phenotype on the CTLA-4+ subset (lower panel) of CCR7+ CD4SP thymocytes from B6 mice ('Wild-type') or female B6.Foxp3^+/null and male B6.Foxp3^null/y littermates aged 6–20 days. (c, d) Graphs show the frequencies of (c) CTLA-4+ cells or (d) Helios+ cells, as gated in (b), with each symbol representing one mouse