Maintenance of FoxP3 expression in the absence of IL-7. Flow cytometric analysis of CD25 and FOXP3 expression in gated Ly5.1⁺ cells, 2.5 weeks after transfer of sorted splenic CD4⁺CD25⁺ cells into irradiated Rag-2^–/– (left panel) and IL-7^–/– (right panel) mice. A representative flow cytometric analysis of a group of 4 mice is shown.